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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementLineItems" xml:lang="en-US">Statement [Line Items]</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AssetsCurrentAbstract" xml:lang="en-US">Current assets:</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PrepaidExpenseCurrent" xml:lang="en-US">Prepaid expenses and deposits</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AssetsCurrent" xml:lang="en-US">Assets, Current</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_AssetsCurrent" xml:lang="en-US">Total current assets</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_Assets" xml:lang="en-US">Total assets</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LiabilitiesCurrentAbstract" xml:lang="en-US">Current liabilities:</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeLiabilitiesCurrent" xml:lang="en-US">Derivative Liability, Current</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_DerivativeLiabilitiesCurrent" xml:lang="en-US">Warrant liability</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeLiabilitiesCurrent" xlink:to="lab_us-gaap_DerivativeLiabilitiesCurrent" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NotesPayableCurrent" xlink:label="loc_us-gaap_NotesPayableCurrent" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NotesPayableCurrent" xml:lang="en-US">Notes Payable, Current</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_NotesPayableCurrent" xml:lang="en-US">Promissory note</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NotesPayableCurrent" xlink:to="lab_us-gaap_NotesPayableCurrent" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LiabilitiesCurrent" xml:lang="en-US">Liabilities, Current</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_LiabilitiesCurrent" xml:lang="en-US">Total current liabilities</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesCurrent" xlink:to="lab_us-gaap_LiabilitiesCurrent" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaap_Liabilities" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_Liabilities" xml:lang="en-US">Liabilities</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_Liabilities" xml:lang="en-US">Total liabilities</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Liabilities" xlink:to="lab_us-gaap_Liabilities" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="loc_us-gaap_CommitmentsAndContingencies" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommitmentsAndContingencies" xml:lang="en-US">Commitments and Contingencies</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommitmentsAndContingencies" xml:lang="en-US">COMMITMENTS AND CONTINGENCIES</label>
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<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity" xml:lang="en-US">Liabilities and Equity</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity" xml:lang="en-US">Total liabilities and stockholders' equity</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="lab_us-gaap_LiabilitiesAndStockholdersEquity" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="loc_us-gaap_StockholdersEquityAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockholdersEquityAbstract" xml:lang="en-US">Stockholders' Equity Attributable to Parent [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_StockholdersEquityAbstract" xml:lang="en-US">Stockholders' equity:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityAbstract" xlink:to="lab_us-gaap_StockholdersEquityAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockholdersEquity" xml:lang="en-US">Stockholders' Equity Attributable to Parent</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_StockholdersEquity" xml:lang="en-US">Total stockholders' equity</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_StockholdersEquity" xml:lang="en-US">Balance, Amount</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_StockholdersEquity" xml:lang="en-US">Balance, Amount</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquity" xlink:to="lab_us-gaap_StockholdersEquity" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockValue" xlink:label="loc_us-gaap_PreferredStockValue" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PreferredStockValue" xml:lang="en-US">Preferred Stock, Value, Issued</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_PreferredStockValue" xml:lang="en-US">Preferred Stock, Value</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockValue" xlink:to="lab_us-gaap_PreferredStockValue" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaap_CommonStockValue" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockValue" xml:lang="en-US">Common Stock, Value, Issued</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_CommonStockValue" xml:lang="en-US">Common stock, $0.001 par value, 41.7 million shares authorized, 13.8 million and 10.6 million shares issued and outstanding as of September 30, 2018 and December 31, 2017, respectively</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockValue" xlink:to="lab_us-gaap_CommonStockValue" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaap_AdditionalPaidInCapital" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AdditionalPaidInCapital" xml:lang="en-US">Additional Paid in Capital</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AdditionalPaidInCapital" xml:lang="en-US">Additional paid-in capital</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdditionalPaidInCapital" xlink:to="lab_us-gaap_AdditionalPaidInCapital" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RetainedEarningsAccumulatedDeficit" xml:lang="en-US">Retained Earnings (Accumulated Deficit)</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RetainedEarningsAccumulatedDeficit" xml:lang="en-US">Accumulated deficit</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetainedEarningsAccumulatedDeficit" xlink:to="lab_us-gaap_RetainedEarningsAccumulatedDeficit" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeriesBPreferredStockMember" xlink:label="loc_us-gaap_SeriesBPreferredStockMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SeriesBPreferredStockMember" xml:lang="en-US">Series B Preferred Stock [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SeriesBPreferredStockMember" xml:lang="en-US">Series B Preferred Stock [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SeriesBPreferredStockMember" xlink:to="lab_us-gaap_SeriesBPreferredStockMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeriesAPreferredStockMember" xlink:label="loc_us-gaap_SeriesAPreferredStockMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SeriesAPreferredStockMember" xml:lang="en-US">Series A Preferred Stock [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SeriesAPreferredStockMember" xml:lang="en-US">Series A Preferred Stock [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SeriesAPreferredStockMember" xlink:to="lab_us-gaap_SeriesAPreferredStockMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaap_CommonStockSharesAuthorized" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockSharesAuthorized" xml:lang="en-US">Common Stock, Shares Authorized</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonStockSharesAuthorized" xml:lang="en-US">Common stock shares authorized</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesAuthorized" xlink:to="lab_us-gaap_CommonStockSharesAuthorized" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaap_CommonStockSharesIssued" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockSharesIssued" xml:lang="en-US">Common Stock, Shares, Issued</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonStockSharesIssued" xml:lang="en-US">Common stock shares issued</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesIssued" xlink:to="lab_us-gaap_CommonStockSharesIssued" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xml:lang="en-US">Common Stock, Shares, Outstanding</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xml:lang="en-US">Common stock shares outstanding</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesOutstanding" xlink:to="lab_us-gaap_CommonStockSharesOutstanding" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockSharesIssued" xlink:label="loc_us-gaap_PreferredStockSharesIssued" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PreferredStockSharesIssued" xml:lang="en-US">Preferred Stock, Shares Issued</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PreferredStockSharesIssued" xml:lang="en-US">Preferred stock issued</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesIssued" xlink:to="lab_us-gaap_PreferredStockSharesIssued" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PreferredStockSharesOutstanding" xml:lang="en-US">Preferred Stock, Shares Outstanding</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PreferredStockSharesOutstanding" xml:lang="en-US">Preferred stock outstanding</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesOutstanding" xlink:to="lab_us-gaap_PreferredStockSharesOutstanding" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockParOrStatedValuePerShare" xml:lang="en-US">Common Stock, Par or Stated Value Per Share</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_CommonStockParOrStatedValuePerShare" xml:lang="en-US">Common stock shares par value</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockParOrStatedValuePerShare" xlink:to="lab_us-gaap_CommonStockParOrStatedValuePerShare" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PreferredStockSharesAuthorized" xml:lang="en-US">Preferred Stock, Shares Authorized</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PreferredStockSharesAuthorized" xml:lang="en-US">Preferred stock shares authorized/designated</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesAuthorized" xlink:to="lab_us-gaap_PreferredStockSharesAuthorized" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PreferredStockParOrStatedValuePerShare" xml:lang="en-US">Preferred Stock, Par or Stated Value Per Share</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PreferredStockParOrStatedValuePerShare" xml:lang="en-US">Preferred stock par value</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockParOrStatedValuePerShare" xlink:to="lab_us-gaap_PreferredStockParOrStatedValuePerShare" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementAbstract" xlink:label="loc_us-gaap_IncomeStatementAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeStatementAbstract" xml:lang="en-US">Income Statement [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="lab_us-gaap_IncomeStatementAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostsAndExpensesAbstract" xlink:label="loc_us-gaap_CostsAndExpensesAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CostsAndExpensesAbstract" xml:lang="en-US">Costs and Expenses [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CostsAndExpensesAbstract" xml:lang="en-US">Operating expenses:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostsAndExpensesAbstract" xlink:to="lab_us-gaap_CostsAndExpensesAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpense" xml:lang="en-US">Research and Development Expense</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpense" xml:lang="en-US">Research and development</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ResearchAndDevelopmentExpense" xlink:to="lab_us-gaap_ResearchAndDevelopmentExpense" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GeneralAndAdministrativeExpense" xml:lang="en-US">General and Administrative Expense</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_GeneralAndAdministrativeExpense" xml:lang="en-US">General and administrative</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GeneralAndAdministrativeExpense" xlink:to="lab_us-gaap_GeneralAndAdministrativeExpense" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaap_OperatingExpenses" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingExpenses" xml:lang="en-US">Operating Expenses</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_OperatingExpenses" xml:lang="en-US">Total operating expenses</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingExpenses" xlink:to="lab_us-gaap_OperatingExpenses" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingIncomeLoss" xml:lang="en-US">Operating Income (Loss)</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_OperatingIncomeLoss" xml:lang="en-US">Loss from operations</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingIncomeLoss" xlink:to="lab_us-gaap_OperatingIncomeLoss" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NonoperatingIncomeExpenseAbstract" xlink:label="loc_us-gaap_NonoperatingIncomeExpenseAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NonoperatingIncomeExpenseAbstract" xml:lang="en-US">Nonoperating Income (Expense) [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NonoperatingIncomeExpenseAbstract" xml:lang="en-US">Other income (expense):</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract" xlink:to="lab_us-gaap_NonoperatingIncomeExpenseAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeGainLossOnDerivativeNet" xlink:label="loc_us-gaap_DerivativeGainLossOnDerivativeNet" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeGainLossOnDerivativeNet" xml:lang="en-US">Derivative, Gain (Loss) on Derivative, Net</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_DerivativeGainLossOnDerivativeNet" xml:lang="en-US">Change in fair value of warrant liabilities</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeGainLossOnDerivativeNet" xlink:to="lab_us-gaap_DerivativeGainLossOnDerivativeNet" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetIncomeLoss" xml:lang="en-US">Net Income (Loss) Attributable to Parent</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_NetIncomeLoss" xml:lang="en-US">Net loss</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NetIncomeLoss" xml:lang="en-US">Net loss</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/presentationGuidance" xlink:label="lab_us-gaap_NetIncomeLoss" xml:lang="en-US">Net loss</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_NetIncomeLoss" xml:lang="en-US">Net loss</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLoss" xlink:to="lab_us-gaap_NetIncomeLoss" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt" xml:lang="en-US">Gain (Loss) on Extinguishment of Debt</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt" xml:lang="en-US">Debt extinguishment gain</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt" xml:lang="en-US">Debt extinguishment gain</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:to="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareBasicAndDiluted" xlink:label="loc_us-gaap_EarningsPerShareBasicAndDiluted" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EarningsPerShareBasicAndDiluted" xml:lang="en-US">Earnings Per Share, Basic and Diluted</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_EarningsPerShareBasicAndDiluted" xml:lang="en-US">Net loss per share, Basic and Diluted</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EarningsPerShareBasicAndDiluted" xml:lang="en-US">Basic and Diluted</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasicAndDiluted" xlink:to="lab_us-gaap_EarningsPerShareBasicAndDiluted" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:label="loc_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Basic and Diluted</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xml:lang="en-US">Weighted average number of common shares outstanding</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:to="lab_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenuesAbstract" xlink:label="loc_us-gaap_RevenuesAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenuesAbstract" xml:lang="en-US">Revenues [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_RevenuesAbstract" xml:lang="en-US">Revenues:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenuesAbstract" xlink:to="lab_us-gaap_RevenuesAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_Revenues" xml:lang="en-US">Revenues</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_Revenues" xml:lang="en-US">Total revenues</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Revenues" xlink:to="lab_us-gaap_Revenues" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srt_ProductOrServiceAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ProductOrServiceAxis" xml:lang="en-US">Product and Service [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ProductOrServiceAxis" xlink:to="lab_srt_ProductOrServiceAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ProductsAndServicesDomain" xml:lang="en-US">Product and Service [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ProductsAndServicesDomain" xlink:to="lab_srt_ProductsAndServicesDomain" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GrantMember" xlink:label="loc_us-gaap_GrantMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GrantMember" xml:lang="en-US">Grant [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GrantMember" xlink:to="lab_us-gaap_GrantMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfStockholdersEquityAbstract" xlink:label="loc_us-gaap_StatementOfStockholdersEquityAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementOfStockholdersEquityAbstract" xml:lang="en-US">Statement of Stockholders' Equity [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfStockholdersEquityAbstract" xlink:to="lab_us-gaap_StatementOfStockholdersEquityAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementEquityComponentsAxis" xml:lang="en-US">Equity Components [Axis]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StatementEquityComponentsAxis" xml:lang="en-US">Equity Components [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementEquityComponentsAxis" xlink:to="lab_us-gaap_StatementEquityComponentsAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EquityComponentDomain" xml:lang="en-US">Equity Component [Domain]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EquityComponentDomain" xml:lang="en-US">Equity Component [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquityComponentDomain" xlink:to="lab_us-gaap_EquityComponentDomain" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockMember" xml:lang="en-US">Common Stock [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonStockMember" xml:lang="en-US">Common Stock [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockMember" xlink:to="lab_us-gaap_CommonStockMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AdditionalPaidInCapitalMember" xml:lang="en-US">Additional Paid-in Capital [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AdditionalPaidInCapitalMember" xml:lang="en-US">Additional Paid In Capital [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdditionalPaidInCapitalMember" xlink:to="lab_us-gaap_AdditionalPaidInCapitalMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RetainedEarningsMember" xml:lang="en-US">Retained Earnings [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RetainedEarningsMember" xml:lang="en-US">Accumulated Deficit [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetainedEarningsMember" xlink:to="lab_us-gaap_RetainedEarningsMember" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_PrivatePlacementShare" xlink:label="loc_mrkr_PrivatePlacementShare" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_PrivatePlacementShare" xml:lang="en-US">Private Placement Share</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_PrivatePlacementShare" xml:lang="en-US">Issuance of common stock in private placement, Share</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_PrivatePlacementShare" xlink:to="lab_mrkr_PrivatePlacementShare" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_PrivatePlacementShare" xml:lang="en-US">Private placement share.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_WarrantOfCashlessExercised" xlink:label="loc_mrkr_WarrantOfCashlessExercised" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_WarrantOfCashlessExercised" xml:lang="en-US">Warrant of Cashless Exercised</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:label="lab_mrkr_WarrantOfCashlessExercised" xml:lang="en-US">Stock warrants cashless exercised, Amount</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_WarrantOfCashlessExercised" xlink:to="lab_mrkr_WarrantOfCashlessExercised" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_WarrantOfCashlessExercised" xml:lang="en-US">The value of warrant exercised of non cash transaction amount.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_WarrantOfCashlessExercisedSharesIssued" xlink:label="loc_mrkr_WarrantOfCashlessExercisedSharesIssued" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_WarrantOfCashlessExercisedSharesIssued" xml:lang="en-US">Warrant of Cashless Exercised shares issued</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:label="lab_mrkr_WarrantOfCashlessExercisedSharesIssued" xml:lang="en-US">Stock warrants cashless exercised, Share</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_WarrantOfCashlessExercisedSharesIssued" xlink:to="lab_mrkr_WarrantOfCashlessExercisedSharesIssued" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_WarrantOfCashlessExercisedSharesIssued" xml:lang="en-US">The warrant exercised of non cash transaction shares issued.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xml:lang="en-US">Adjustments to Additional Paid in Capital, Warrant Issued</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xml:lang="en-US">Fair value of repriced warrants as inducement</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:to="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ExerciseOfWarrantsShare" xlink:label="loc_mrkr_ExerciseOfWarrantsShare" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ExerciseOfWarrantsShare" xml:lang="en-US">Exercise Of Warrants Share</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_ExerciseOfWarrantsShare" xml:lang="en-US">Stock warrants exercised for cash, Share</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ExerciseOfWarrantsShare" xlink:to="lab_mrkr_ExerciseOfWarrantsShare" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ExerciseOfWarrantsShare" xml:lang="en-US">Exercise of warrants share.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ExerciseOfWarrantsAmount" xlink:label="loc_mrkr_ExerciseOfWarrantsAmount" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ExerciseOfWarrantsAmount" xml:lang="en-US">Exercise Of Warrants Amount</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:label="lab_mrkr_ExerciseOfWarrantsAmount" xml:lang="en-US">Stock warrants exercised for cash, Amount</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ExerciseOfWarrantsAmount" xlink:to="lab_mrkr_ExerciseOfWarrantsAmount" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ExerciseOfWarrantsAmount" xml:lang="en-US">Exercise of warrants amount.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharesIssued" xlink:label="loc_us-gaap_SharesIssued" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SharesIssued" xml:lang="en-US">Shares, Issued</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_SharesIssued" xml:lang="en-US">Balance, Share</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_SharesIssued" xml:lang="en-US">Balance, Share</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharesIssued" xlink:to="lab_us-gaap_SharesIssued" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" xml:lang="en-US">Stock Issued During Period, Value, Stock Options Exercised</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" xml:lang="en-US">Stock options exercised for cash, Amount</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" xlink:to="lab_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xml:lang="en-US">Stock options exercised for cash, Share</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xml:lang="en-US">Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xml:lang="en-US">Stock-based compensation, Amount</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:to="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross" xml:lang="en-US">Stock Issued During Period, Shares, Share-based Compensation, Gross</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross" xml:lang="en-US">Stock-based compensation, Share</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_PrivatePlacementAmount" xlink:label="loc_mrkr_PrivatePlacementAmount" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_PrivatePlacementAmount" xml:lang="en-US">Private Placement Amount</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_PrivatePlacementAmount" xml:lang="en-US">Issuance of common stock in private placement, Amount</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_PrivatePlacementAmount" xlink:to="lab_mrkr_PrivatePlacementAmount" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_PrivatePlacementAmount" xml:lang="en-US">Private placement amount.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="loc_us-gaap_StatementOfCashFlowsAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementOfCashFlowsAbstract" xml:lang="en-US">Statement of Cash Flows [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract" xlink:to="lab_us-gaap_StatementOfCashFlowsAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xml:lang="en-US">Cash Flows from Operating Activities:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xml:lang="en-US">Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xml:lang="en-US">Reconciliation of net loss to net cash used in operating activities:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInDerivativeLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInDerivativeLiabilities" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInDerivativeLiabilities" xml:lang="en-US">Increase (Decrease) in Derivative Liabilities</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInDerivativeLiabilities" xml:lang="en-US">Changes in fair value of warrant liabilities</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInDerivativeLiabilities" xlink:to="lab_us-gaap_IncreaseDecreaseInDerivativeLiabilities" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaap_ShareBasedCompensation" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensation" xml:lang="en-US">Share-based Compensation</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensation" xml:lang="en-US">Stock-based compensation</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensation" xlink:to="lab_us-gaap_ShareBasedCompensation" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xml:lang="en-US">Increase (Decrease) in Operating Capital [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xml:lang="en-US">Changes in operating assets and liabilities:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:to="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidExpense" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInPrepaidExpense" xml:lang="en-US">Increase (Decrease) in Prepaid Expense</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInPrepaidExpense" xml:lang="en-US">Prepaid expenses and deposits</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:to="lab_us-gaap_IncreaseDecreaseInPrepaidExpense" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xml:lang="en-US">Increase (Decrease) in Accounts Payable and Accrued Liabilities</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xml:lang="en-US">Accounts payable and accrued expenses</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:to="lab_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xml:lang="en-US">Net cash used in operating activities</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xlink:label="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xml:lang="en-US">Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xml:lang="en-US">Supplemental schedule of non-cash financing activities:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xlink:to="lab_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_NoncashOrPartNoncashTransactionFairValueOfRepricedWarrantsAsInducement" xlink:label="loc_mrkr_NoncashOrPartNoncashTransactionFairValueOfRepricedWarrantsAsInducement" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_NoncashOrPartNoncashTransactionFairValueOfRepricedWarrantsAsInducement" xml:lang="en-US">Noncash or Part Noncash Transaction Fair Value Of Repriced Warrants As Inducement</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_NoncashOrPartNoncashTransactionFairValueOfRepricedWarrantsAsInducement" xml:lang="en-US">Fair value of repriced warrants as inducement</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_NoncashOrPartNoncashTransactionFairValueOfRepricedWarrantsAsInducement" xlink:to="lab_mrkr_NoncashOrPartNoncashTransactionFairValueOfRepricedWarrantsAsInducement" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_NoncashOrPartNoncashTransactionFairValueOfRepricedWarrantsAsInducement" xml:lang="en-US">Fair value of repriced warrants as inducement which classified as non financing and investing activities.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_NonCashExcerciseOfWarrantsAmount" xlink:label="loc_mrkr_NonCashExcerciseOfWarrantsAmount" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_NonCashExcerciseOfWarrantsAmount" xml:lang="en-US">Non Cash Excercise Of Warrants Amount</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_NonCashExcerciseOfWarrantsAmount" xml:lang="en-US">Stock warrants cashless exercised</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_NonCashExcerciseOfWarrantsAmount" xml:lang="en-US">Non Cash Excercise Of Warrants Amount</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_NonCashExcerciseOfWarrantsAmount" xlink:to="lab_mrkr_NonCashExcerciseOfWarrantsAmount" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_NonCashExcerciseOfWarrantsAmount" xml:lang="en-US">The value of warrant exercised of non cash amount transaction.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xml:lang="en-US">Cash Flows from Financing Activities:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ProceedsFromIssuanceOfCommonStockAndWarrantsInPrivatePlacement" xlink:label="loc_mrkr_ProceedsFromIssuanceOfCommonStockAndWarrantsInPrivatePlacement" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ProceedsFromIssuanceOfCommonStockAndWarrantsInPrivatePlacement" xml:lang="en-US">Proceeds From Issuance Of Common Stock And WarrantsIn Private Placement</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_ProceedsFromIssuanceOfCommonStockAndWarrantsInPrivatePlacement" xml:lang="en-US">Proceeds from issuance of common stock and warrants in private placement, net of offering costs</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ProceedsFromIssuanceOfCommonStockAndWarrantsInPrivatePlacement" xlink:to="lab_mrkr_ProceedsFromIssuanceOfCommonStockAndWarrantsInPrivatePlacement" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ProceedsFromIssuanceOfCommonStockAndWarrantsInPrivatePlacement" xml:lang="en-US">The cash inflow from the additional capital contribution to the entity due to issue of common stock and warrants in a private placement.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromWarrantExercises" xlink:label="loc_us-gaap_ProceedsFromWarrantExercises" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProceedsFromWarrantExercises" xml:lang="en-US">Proceeds from Warrant Exercises</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ProceedsFromWarrantExercises" xml:lang="en-US">Proceeds from exercise of stock warrants, net of offering costs</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromWarrantExercises" xlink:to="lab_us-gaap_ProceedsFromWarrantExercises" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromStockOptionsExercised" xlink:label="loc_us-gaap_ProceedsFromStockOptionsExercised" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProceedsFromStockOptionsExercised" xml:lang="en-US">Proceeds from Stock Options Exercised</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ProceedsFromStockOptionsExercised" xml:lang="en-US">Proceeds from exercise of stock options</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromStockOptionsExercised" xlink:to="lab_us-gaap_ProceedsFromStockOptionsExercised" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" xml:lang="en-US">Net cash provided by financing activities</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfCommonStock" xml:lang="en-US">Payments for Repurchase of Common Stock</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfCommonStock" xml:lang="en-US">Repurchase of common stock to pay for employee withholding taxes</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:to="lab_us-gaap_PaymentsForRepurchaseOfCommonStock" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashPeriodIncreaseDecrease" xlink:label="loc_us-gaap_CashPeriodIncreaseDecrease" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashPeriodIncreaseDecrease" xml:lang="en-US">Cash, Period Increase (Decrease)</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_CashPeriodIncreaseDecrease" xml:lang="en-US">Net decrease in cash</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashPeriodIncreaseDecrease" xlink:to="lab_us-gaap_CashPeriodIncreaseDecrease" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xml:lang="en-US">Organization, Consolidation and Presentation of Financial Statements [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NatureOfOperations" xlink:label="loc_us-gaap_NatureOfOperations" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NatureOfOperations" xml:lang="en-US">Nature of Operations [Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_NatureOfOperations" xml:lang="en-US">NATURE OF OPERATIONS</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NatureOfOperations" xlink:to="lab_us-gaap_NatureOfOperations" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BasisOfAccounting" xlink:label="loc_us-gaap_BasisOfAccounting" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BasisOfAccounting" xml:lang="en-US">Basis of Accounting [Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BasisOfAccounting" xml:lang="en-US">BASIS OF PRESENTATION</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BasisOfAccounting" xlink:to="lab_us-gaap_BasisOfAccounting" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TextBlockAbstract" xlink:label="loc_us-gaap_TextBlockAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TextBlockAbstract" xml:lang="en-US">Text Block [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TextBlockAbstract" xlink:to="lab_us-gaap_TextBlockAbstract" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_LiquidityAndFinancialConditionTextBlock" xlink:label="loc_mrkr_LiquidityAndFinancialConditionTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_LiquidityAndFinancialConditionTextBlock" xml:lang="en-US">Liquidity And Financial Condition [Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_LiquidityAndFinancialConditionTextBlock" xml:lang="en-US">LIQUIDITY AND FINANCIAL CONDITION</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_LiquidityAndFinancialConditionTextBlock" xlink:to="lab_mrkr_LiquidityAndFinancialConditionTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_LiquidityAndFinancialConditionTextBlock" xml:lang="en-US">Liquidity and financial condition text block.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccountingPoliciesAbstract" xml:lang="en-US">Accounting Policies [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingPoliciesAbstract" xlink:to="lab_us-gaap_AccountingPoliciesAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SignificantAccountingPoliciesTextBlock" xlink:label="loc_us-gaap_SignificantAccountingPoliciesTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SignificantAccountingPoliciesTextBlock" xml:lang="en-US">Significant Accounting Policies [Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_SignificantAccountingPoliciesTextBlock" xml:lang="en-US">SIGNIFICANT ACCOUNTING POLICIES</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SignificantAccountingPoliciesTextBlock" xlink:to="lab_us-gaap_SignificantAccountingPoliciesTextBlock" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncontrollingInterestAbstract" xlink:label="loc_us-gaap_NoncontrollingInterestAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NoncontrollingInterestAbstract" xml:lang="en-US">Noncontrolling Interest [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncontrollingInterestAbstract" xlink:to="lab_us-gaap_NoncontrollingInterestAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MinorityInterestDisclosureTextBlock" xlink:label="loc_us-gaap_MinorityInterestDisclosureTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MinorityInterestDisclosureTextBlock" xml:lang="en-US">Noncontrolling Interest Disclosure [Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_MinorityInterestDisclosureTextBlock" xml:lang="en-US">NET LOSS PER SHARE APPLICABLE TO COMMON SHAREHOLDER</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MinorityInterestDisclosureTextBlock" xlink:to="lab_us-gaap_MinorityInterestDisclosureTextBlock" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_DerivativesAndFairValueAbstract" xlink:label="loc_mrkr_DerivativesAndFairValueAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_DerivativesAndFairValueAbstract" xml:lang="en-US">Derivatives and Fair Value [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_DerivativesAndFairValueAbstract" xlink:to="lab_mrkr_DerivativesAndFairValueAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativesAndFairValueTextBlock" xlink:label="loc_us-gaap_DerivativesAndFairValueTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativesAndFairValueTextBlock" xml:lang="en-US">Derivatives and Fair Value [Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_DerivativesAndFairValueTextBlock" xml:lang="en-US">WARRANT LIABILITY AND FAIR VALUE MEASUREMENTS</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativesAndFairValueTextBlock" xlink:to="lab_us-gaap_DerivativesAndFairValueTextBlock" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityNoteAbstract" xlink:label="loc_us-gaap_StockholdersEquityNoteAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockholdersEquityNoteAbstract" xml:lang="en-US">Stockholders' Equity Note [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteAbstract" xlink:to="lab_us-gaap_StockholdersEquityNoteAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:label="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xml:lang="en-US">Stockholders' Equity Note Disclosure [Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xml:lang="en-US">STOCKHOLDERS' EQUITY</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:to="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xml:lang="en-US">Disclosure of Compensation Related Costs, Share-based Payments [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:to="lab_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:label="loc_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xml:lang="en-US">Disclosure of Compensation Related Costs, Share-based Payments [Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xml:lang="en-US">STOCK-BASED COMPENSATION</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:to="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_GrantIncomeAbstract" xlink:label="loc_mrkr_GrantIncomeAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_GrantIncomeAbstract" xml:lang="en-US">Grant Income [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_GrantIncomeAbstract" xlink:to="lab_mrkr_GrantIncomeAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_GrantIncomeAbstract" xml:lang="en-US">Grant Income (Abstract)</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_GrantIncomeTextBlock" xlink:label="loc_mrkr_GrantIncomeTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_GrantIncomeTextBlock" xml:lang="en-US">Grant Income [Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_GrantIncomeTextBlock" xml:lang="en-US">GRANT INCOME</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_GrantIncomeTextBlock" xlink:to="lab_mrkr_GrantIncomeTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_GrantIncomeTextBlock" xml:lang="en-US">The entire disclosure of grant income.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="loc_us-gaap_SubsequentEventsAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsequentEventsAbstract" xml:lang="en-US">Subsequent Events [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsAbstract" xlink:to="lab_us-gaap_SubsequentEventsAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="loc_us-gaap_SubsequentEventsTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsequentEventsTextBlock" xml:lang="en-US">Subsequent Events [Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_SubsequentEventsTextBlock" xml:lang="en-US">SUBSEQUENT EVENT</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsTextBlock" xlink:to="lab_us-gaap_SubsequentEventsTextBlock" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xml:lang="en-US">New Accounting Pronouncements, Policy [Policy Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xml:lang="en-US">New Accounting Pronouncements</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:to="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xml:lang="en-US">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xml:lang="en-US">Schedule of Earnings Per Share, Basic and Diluted</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_NetLossPerShareTableTextBlock" xlink:label="loc_mrkr_NetLossPerShareTableTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_NetLossPerShareTableTextBlock" xml:lang="en-US">Net Loss Per Share [Table Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_NetLossPerShareTableTextBlock" xml:lang="en-US">Net Loss Per Share</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_NetLossPerShareTableTextBlock" xlink:to="lab_mrkr_NetLossPerShareTableTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_NetLossPerShareTableTextBlock" xml:lang="en-US">Net Loss Per Share</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ValuationMethodology" xlink:label="loc_mrkr_ValuationMethodology" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ValuationMethodology" xml:lang="en-US">Valuation Methodology</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_ValuationMethodology" xml:lang="en-US">Valuation Methodology</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ValuationMethodology" xlink:to="lab_mrkr_ValuationMethodology" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ValuationMethodology" xml:lang="en-US">Valuation methodology.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_FinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis" xlink:label="loc_mrkr_FinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_FinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis" xml:lang="en-US">Financial Assets And Liabilities Measured At Fair Value On Recurring Basis</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_FinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis" xml:lang="en-US">Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_FinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis" xlink:to="lab_mrkr_FinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_FinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis" xml:lang="en-US">Financial assets and liabilities measured at fair value on recurring basis.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_MeasuredAtFairValue" xlink:label="loc_mrkr_MeasuredAtFairValue" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_MeasuredAtFairValue" xml:lang="en-US">Measured At Fair Value</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_MeasuredAtFairValue" xml:lang="en-US">Schedule of Changes in Level 3 Liabilities Measured at Fair Value</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_MeasuredAtFairValue" xlink:to="lab_mrkr_MeasuredAtFairValue" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_MeasuredAtFairValue" xml:lang="en-US">Measured at fair value.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_SharePurchaseWarrantsTableTextBlock" xlink:label="loc_mrkr_SharePurchaseWarrantsTableTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_SharePurchaseWarrantsTableTextBlock" xml:lang="en-US">Share Purchase Warrants [Table Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_SharePurchaseWarrantsTableTextBlock" xml:lang="en-US">Schedule of share purchase warrants</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_SharePurchaseWarrantsTableTextBlock" xlink:to="lab_mrkr_SharePurchaseWarrantsTableTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_SharePurchaseWarrantsTableTextBlock" xml:lang="en-US">Tabular disclosure of share purchase warrants.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ValuationMethodologyTableTextBlock" xlink:label="loc_mrkr_ValuationMethodologyTableTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ValuationMethodologyTableTextBlock" xml:lang="en-US">Valuation Methodology [Table Text Block]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_ValuationMethodologyTableTextBlock" xml:lang="en-US">Schedule of weighted average valuation methodology</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ValuationMethodologyTableTextBlock" xlink:to="lab_mrkr_ValuationMethodologyTableTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ValuationMethodologyTableTextBlock" xml:lang="en-US">Tabular disclosure of valuation methodology.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_StockbasedCompensationExpensesTableTextBlock" xlink:label="loc_mrkr_StockbasedCompensationExpensesTableTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_StockbasedCompensationExpensesTableTextBlock" xml:lang="en-US">Stockbased Compensation Expenses [Table Text Block]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_StockbasedCompensationExpensesTableTextBlock" xlink:to="lab_mrkr_StockbasedCompensationExpensesTableTextBlock" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_StockbasedCompensationExpensesTableTextBlock" xml:lang="en-US">Tabular disclosure of stock based compenstaion expenses recorded.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" xlink:label="loc_us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" xml:lang="en-US">Schedule of Collaborative Arrangements and Non-collaborative Arrangement Transactions [Table]</label>
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<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:label="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xml:lang="en-US">Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="lab_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" xlink:label="loc_us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" xml:lang="en-US">Business Acquisition, Equity Interest Issued or Issuable, Number of Shares</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" xlink:to="lab_us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionAxis" xml:lang="en-US">Business Acquisition [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionAxis" xlink:to="lab_us-gaap_BusinessAcquisitionAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionAcquireeDomain" xml:lang="en-US">Business Acquisition, Acquiree [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain" xlink:to="lab_us-gaap_BusinessAcquisitionAcquireeDomain" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_MarkerTherapeuticsIncMember" xlink:label="loc_mrkr_MarkerTherapeuticsIncMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_MarkerTherapeuticsIncMember" xml:lang="en-US">Marker TherapeuticsInc [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_MarkerTherapeuticsIncMember" xlink:to="lab_mrkr_MarkerTherapeuticsIncMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_MarkerTherapeuticsIncMember" xml:lang="en-US">MarkerTherapeuticsIncMember</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsequentEventTypeAxis" xml:lang="en-US">Subsequent Event Type [Axis]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_SubsequentEventTypeAxis" xml:lang="en-US">Eastern Capital Limited [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventTypeAxis" xlink:to="lab_us-gaap_SubsequentEventTypeAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsequentEventTypeDomain" xml:lang="en-US">Subsequent Event Type [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventTypeDomain" xlink:to="lab_us-gaap_SubsequentEventTypeDomain" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsequentEventMember" xml:lang="en-US">Subsequent Event [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventMember" xlink:to="lab_us-gaap_SubsequentEventMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:label="loc_us-gaap_ClassOfWarrantOrRightAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ClassOfWarrantOrRightAxis" xml:lang="en-US">Class of Warrant or Right [Axis]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ClassOfWarrantOrRightAxis" xml:lang="en-US">Class of Warrant or Right [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightAxis" xlink:to="lab_us-gaap_ClassOfWarrantOrRightAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:label="loc_us-gaap_ClassOfWarrantOrRightDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ClassOfWarrantOrRightDomain" xml:lang="en-US">Class of Warrant or Right [Domain]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ClassOfWarrantOrRightDomain" xml:lang="en-US">Class of Warrant or Right [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain" xlink:to="lab_us-gaap_ClassOfWarrantOrRightDomain" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_WarrantMember" xlink:label="loc_us-gaap_WarrantMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_WarrantMember" xml:lang="en-US">Warrant [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WarrantMember" xlink:to="lab_us-gaap_WarrantMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashAndCashEquivalentsAbstract" xlink:label="loc_us-gaap_CashAndCashEquivalentsAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashAndCashEquivalentsAbstract" xml:lang="en-US">Cash and Cash Equivalents [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsAbstract" xlink:to="lab_us-gaap_CashAndCashEquivalentsAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfCashAndCashEquivalentsTable" xlink:label="loc_us-gaap_ScheduleOfCashAndCashEquivalentsTable" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfCashAndCashEquivalentsTable" xml:lang="en-US">Schedule of Cash and Cash Equivalents [Table]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfCashAndCashEquivalentsTable" xlink:to="lab_us-gaap_ScheduleOfCashAndCashEquivalentsTable" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashAndCashEquivalentsLineItems" xlink:label="loc_us-gaap_CashAndCashEquivalentsLineItems" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashAndCashEquivalentsLineItems" xml:lang="en-US">Cash and Cash Equivalents [Line Items]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems" xlink:to="lab_us-gaap_CashAndCashEquivalentsLineItems" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashEquivalentsAtCarryingValue" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashEquivalentsAtCarryingValue" xml:lang="en-US">Cash Equivalents, at Carrying Value</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashEquivalentsAtCarryingValue" xlink:to="lab_us-gaap_CashEquivalentsAtCarryingValue" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ClassOfWarrantOrRightWarrantsExpirationTerm" xlink:label="loc_mrkr_ClassOfWarrantOrRightWarrantsExpirationTerm" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ClassOfWarrantOrRightWarrantsExpirationTerm" xml:lang="en-US">Class of Warrant or Right Warrants Expiration Term</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ClassOfWarrantOrRightWarrantsExpirationTerm" xlink:to="lab_mrkr_ClassOfWarrantOrRightWarrantsExpirationTerm" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ClassOfWarrantOrRightWarrantsExpirationTerm" xml:lang="en-US">Period of warrants, in which they are exercisable.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromIssuanceOfPrivatePlacement" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfPrivatePlacement" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfPrivatePlacement" xml:lang="en-US">Proceeds from Issuance of Private Placement</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfPrivatePlacement" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfPrivatePlacement" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsidiarySaleOfStockAxis" xml:lang="en-US">Sale of Stock [Axis]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SubsidiarySaleOfStockAxis" xml:lang="en-US">Sale of Stock [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis" xlink:to="lab_us-gaap_SubsidiarySaleOfStockAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SaleOfStockNameOfTransactionDomain" xml:lang="en-US">Sale of Stock [Domain]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SaleOfStockNameOfTransactionDomain" xml:lang="en-US">Sale of Stock [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain" xlink:to="lab_us-gaap_SaleOfStockNameOfTransactionDomain" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PrivatePlacementMember" xlink:label="loc_us-gaap_PrivatePlacementMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PrivatePlacementMember" xml:lang="en-US">Private Placement [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PrivatePlacementMember" xlink:to="lab_us-gaap_PrivatePlacementMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EarningsPerShareAbstract" xml:lang="en-US">Earnings Per Share [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareAbstract" xlink:to="lab_us-gaap_EarningsPerShareAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLossAttributableToParentDilutedAbstract" xlink:label="loc_us-gaap_NetIncomeLossAttributableToParentDilutedAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetIncomeLossAttributableToParentDilutedAbstract" xml:lang="en-US">Net Income (Loss) Attributable to Parent, Diluted [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_NetIncomeLossAttributableToParentDilutedAbstract" xml:lang="en-US">Numerator:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLossAttributableToParentDilutedAbstract" xlink:to="lab_us-gaap_NetIncomeLossAttributableToParentDilutedAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Diluted [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" xml:lang="en-US">Denominator:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" xlink:to="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Basic</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xml:lang="en-US">Weighted average common shares outstanding</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:to="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareBasicAndDilutedAbstract" xlink:label="loc_us-gaap_EarningsPerShareBasicAndDilutedAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EarningsPerShareBasicAndDilutedAbstract" xml:lang="en-US">Earnings Per Share, Basic and Diluted [Abstract]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_EarningsPerShareBasicAndDilutedAbstract" xml:lang="en-US">Net loss per share data:</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasicAndDilutedAbstract" xlink:to="lab_us-gaap_EarningsPerShareBasicAndDilutedAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xml:lang="en-US">Potentially dilutive securities</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems" xml:lang="en-US">Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SharePrice" xml:lang="en-US">Stock price</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MeasurementInputTypeDomain" xml:lang="en-US">Measurement Input Type [Domain]</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MeasurementInputPriceVolatilityMember" xml:lang="en-US">Measurement Input, Price Volatility [Member]</label>
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<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MeasurementInputRiskFreeInterestRateMember" xlink:label="loc_us-gaap_MeasurementInputRiskFreeInterestRateMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MeasurementInputRiskFreeInterestRateMember" xml:lang="en-US">Measurement Input, Risk Free Interest Rate [Member]</label>
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<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MeasurementInputExpectedDividendRateMember" xlink:label="loc_us-gaap_MeasurementInputExpectedDividendRateMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MeasurementInputExpectedDividendRateMember" xml:lang="en-US">Measurement Input, Expected Dividend Rate [Member]</label>
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<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MeasurementInputSharePriceMember" xlink:label="loc_us-gaap_MeasurementInputSharePriceMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MeasurementInputSharePriceMember" xml:lang="en-US">Measurement Input, Share Price [Member]</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MeasurementInputExpectedTermMember" xml:lang="en-US">Measurement Input, Expected Term [Member]</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_SharePurchaseWarrantsMember" xml:lang="en-US">Share Purchase Warrants [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_SharePurchaseWarrantsMember" xml:lang="en-US">Share Purchase Warrants [Member]</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_SharePurchaseWarrantsMember" xml:lang="en-US">Share Purchase Warrants [Member]</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_HedgingRelationshipDomain" xml:lang="en-US">Hedging Relationship [Domain]</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueHedgingMember" xml:lang="en-US">Fair Value Hedging [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueHedgingMember" xml:lang="en-US">Fair value</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis" xml:lang="en-US">Fair Value, Hierarchy [Axis]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis" xml:lang="en-US">Fair Value, Hierarchy [Axis]</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueInputsLevel1Member" xml:lang="en-US">Quoted prices in active markets (Level 1)</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel1Member" xlink:to="lab_us-gaap_FairValueInputsLevel1Member" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaap_FairValueInputsLevel2Member" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueInputsLevel2Member" xml:lang="en-US">Fair Value, Inputs, Level 2 [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueInputsLevel2Member" xml:lang="en-US">Significant other observable inputs (Level 2)</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel2Member" xlink:to="lab_us-gaap_FairValueInputsLevel2Member" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="loc_us-gaap_FairValueInputsLevel3Member" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueInputsLevel3Member" xml:lang="en-US">Fair Value, Inputs, Level 3 [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueInputsLevel3Member" xml:lang="en-US">Significant other unobservable inputs (Level 3)</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel3Member" xlink:to="lab_us-gaap_FairValueInputsLevel3Member" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativesFairValueLineItems" xlink:label="loc_us-gaap_DerivativesFairValueLineItems" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativesFairValueLineItems" xml:lang="en-US">Derivatives, Fair Value [Line Items]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativesFairValueLineItems" xml:lang="en-US">Derivatives, Fair Value [Line Items]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativesFairValueLineItems" xlink:to="lab_us-gaap_DerivativesFairValueLineItems" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeLiability" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeLiability" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeFairValueOfDerivativeLiability" xml:lang="en-US">Derivative Liability, Fair Value, Gross Liability</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativeFairValueOfDerivativeLiability" xml:lang="en-US">Warrant liability</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeFairValueOfDerivativeLiability" xlink:to="lab_us-gaap_DerivativeFairValueOfDerivativeLiability" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueDisclosuresAbstract" xlink:label="loc_us-gaap_FairValueDisclosuresAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueDisclosuresAbstract" xml:lang="en-US">Fair Value Disclosures [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosuresAbstract" xlink:to="lab_us-gaap_FairValueDisclosuresAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightTable" xlink:label="loc_us-gaap_ClassOfWarrantOrRightTable" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ClassOfWarrantOrRightTable" xml:lang="en-US">Class of Warrant or Right [Table]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightTable" xlink:to="lab_us-gaap_ClassOfWarrantOrRightTable" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightLineItems" xlink:label="loc_us-gaap_ClassOfWarrantOrRightLineItems" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ClassOfWarrantOrRightLineItems" xml:lang="en-US">Class of Warrant or Right [Line Items]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="lab_us-gaap_ClassOfWarrantOrRightLineItems" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xml:lang="en-US">Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xml:lang="en-US">Balance</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xml:lang="en-US">Balance</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xlink:to="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease" xml:lang="en-US">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Period Increase (Decrease)</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease" xml:lang="en-US">Change in fair value of warrant liability</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease" xlink:to="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_WeightedAverageInputsBeforeModificationMember" xlink:label="loc_mrkr_WeightedAverageInputsBeforeModificationMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_WeightedAverageInputsBeforeModificationMember" xml:lang="en-US">Weighted Average Inputs Before Modification [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_WeightedAverageInputsBeforeModificationMember" xml:lang="en-US">Weighted Average Inputs Before Modification [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_WeightedAverageInputsBeforeModificationMember" xlink:to="lab_mrkr_WeightedAverageInputsBeforeModificationMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_WeightedAverageInputsBeforeModificationMember" xml:lang="en-US">Weighted average inputs before modification.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_WeightedAverageInputsAfterModificationMember" xlink:label="loc_mrkr_WeightedAverageInputsAfterModificationMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_WeightedAverageInputsAfterModificationMember" xml:lang="en-US">Weighted Average Inputs After Modification [Member]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_WeightedAverageInputsAfterModificationMember" xml:lang="en-US">Weighted Average Inputs After Modification [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_WeightedAverageInputsAfterModificationMember" xlink:to="lab_mrkr_WeightedAverageInputsAfterModificationMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_WeightedAverageInputsAfterModificationMember" xml:lang="en-US">Weighted average inputs after modification.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_NumberOfWarrantExercisedForCash" xlink:label="loc_mrkr_NumberOfWarrantExercisedForCash" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_NumberOfWarrantExercisedForCash" xml:lang="en-US">Number Of Warrant Exercised for cash</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_NumberOfWarrantExercisedForCash" xml:lang="en-US">Number of Warrant Exercised for cash</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_NumberOfWarrantExercisedForCash" xlink:to="lab_mrkr_NumberOfWarrantExercisedForCash" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_NumberOfWarrantExercisedForCash" xml:lang="en-US">Number of warrants exercised.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightOutstanding" xlink:label="loc_us-gaap_ClassOfWarrantOrRightOutstanding" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ClassOfWarrantOrRightOutstanding" xml:lang="en-US">Class of Warrant or Right, Outstanding</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_ClassOfWarrantOrRightOutstanding" xml:lang="en-US">Number of Warrants, Ending balance</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_ClassOfWarrantOrRightOutstanding" xml:lang="en-US">Number of Warrants, Beginning balance</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightOutstanding" xlink:to="lab_us-gaap_ClassOfWarrantOrRightOutstanding" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ClassOfWarrantOrRightsOutStandingIssuedWeightedAverageExercisePrice" xlink:label="loc_mrkr_ClassOfWarrantOrRightsOutStandingIssuedWeightedAverageExercisePrice" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutStandingIssuedWeightedAverageExercisePrice" xml:lang="en-US">Class Of Warrant Or Rights Out standing Issued Weighted Average Exercise Price</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutStandingIssuedWeightedAverageExercisePrice" xml:lang="en-US">Weighted Average Exercise Price, Issued</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ClassOfWarrantOrRightsOutStandingIssuedWeightedAverageExercisePrice" xlink:to="lab_mrkr_ClassOfWarrantOrRightsOutStandingIssuedWeightedAverageExercisePrice" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutStandingIssuedWeightedAverageExercisePrice" xml:lang="en-US">Class of warrant or rights outstanding issued weighted average exercise price.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ClassOfWarrantOrRightsOutstandingExercisedWeightedAverageExercisedForCash" xlink:label="loc_mrkr_ClassOfWarrantOrRightsOutstandingExercisedWeightedAverageExercisedForCash" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutstandingExercisedWeightedAverageExercisedForCash" xml:lang="en-US">Class Of Warrant Or Rights Outstanding Exercised Weighted Average Exercised for cash</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutstandingExercisedWeightedAverageExercisedForCash" xml:lang="en-US">Weighted Average Exercise Price, Exercised for cash</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ClassOfWarrantOrRightsOutstandingExercisedWeightedAverageExercisedForCash" xlink:to="lab_mrkr_ClassOfWarrantOrRightsOutstandingExercisedWeightedAverageExercisedForCash" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutstandingExercisedWeightedAverageExercisedForCash" xml:lang="en-US">Class of warrant or rights outstanding exercised weighted average exercise price.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_NumberOfWarrantIssued" xlink:label="loc_mrkr_NumberOfWarrantIssued" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_NumberOfWarrantIssued" xml:lang="en-US">Number Of Warrant Issued</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_NumberOfWarrantIssued" xml:lang="en-US">Number of Warrants, Issued</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_NumberOfWarrantIssued" xlink:to="lab_mrkr_NumberOfWarrantIssued" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_NumberOfWarrantIssued" xml:lang="en-US">Number of warrants issued.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageRemainingContractualLife" xlink:label="loc_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageRemainingContractualLife" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageRemainingContractualLife" xml:lang="en-US">Class Of Warrant Or Rights Out standing Weighted Average Remaining Contractual Life</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageRemainingContractualLife" xml:lang="en-US">Weighted Average Remaining Contractual Life, Outstanding (in years)</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageRemainingContractualLife" xlink:to="lab_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageRemainingContractualLife" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageRemainingContractualLife" xml:lang="en-US">Class of warrant or right outstanding issued weighted average remaining life.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_NumberOfWarrantExpiredOrCancelled" xlink:label="loc_mrkr_NumberOfWarrantExpiredOrCancelled" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_NumberOfWarrantExpiredOrCancelled" xml:lang="en-US">Number Of Warrant Expired or Cancelled</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_NumberOfWarrantExpiredOrCancelled" xml:lang="en-US">Number of Warrant Expired or Cancelled</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_NumberOfWarrantExpiredOrCancelled" xlink:to="lab_mrkr_NumberOfWarrantExpiredOrCancelled" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_NumberOfWarrantExpiredOrCancelled" xml:lang="en-US">Number of warrants expired or cancelled.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ClassOfWarrantOrRightsOutstandingCashlessExercisedWeightedAverageExercisePrice" xlink:label="loc_mrkr_ClassOfWarrantOrRightsOutstandingCashlessExercisedWeightedAverageExercisePrice" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutstandingCashlessExercisedWeightedAverageExercisePrice" xml:lang="en-US">Class Of Warrant Or Rights Outstanding Cashless Exercised Weighted Average Exercise Price</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutstandingCashlessExercisedWeightedAverageExercisePrice" xml:lang="en-US">Weighted Average	Exercise Price Cashless exercised</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ClassOfWarrantOrRightsOutstandingCashlessExercisedWeightedAverageExercisePrice" xlink:to="lab_mrkr_ClassOfWarrantOrRightsOutstandingCashlessExercisedWeightedAverageExercisePrice" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutstandingCashlessExercisedWeightedAverageExercisePrice" xml:lang="en-US">Class of warrant or rights outstanding cashless exercised weighted average exercise price.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ClassOfWarrantOrRightsOutstandingExpiredOrCancelledWeightedAverageExercisePrice" xlink:label="loc_mrkr_ClassOfWarrantOrRightsOutstandingExpiredOrCancelledWeightedAverageExercisePrice" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutstandingExpiredOrCancelledWeightedAverageExercisePrice" xml:lang="en-US">Class Of Warrant or Rights Outstanding Expired or Cancelled Weighted Average Exercise Price</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutstandingExpiredOrCancelledWeightedAverageExercisePrice" xml:lang="en-US">Weighted Average	Exercise Price Expired or Cancelled</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ClassOfWarrantOrRightsOutstandingExpiredOrCancelledWeightedAverageExercisePrice" xlink:to="lab_mrkr_ClassOfWarrantOrRightsOutstandingExpiredOrCancelledWeightedAverageExercisePrice" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutstandingExpiredOrCancelledWeightedAverageExercisePrice" xml:lang="en-US">Class of warrant or rights outstanding expired or Cancelled weighted average exercise price.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ClassOfWarrantOrRightOutStandingIntrinsicValue" xlink:label="loc_mrkr_ClassOfWarrantOrRightOutStandingIntrinsicValue" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ClassOfWarrantOrRightOutStandingIntrinsicValue" xml:lang="en-US">Class Of Warrant Or Right Out standing Intrinsic Value</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:label="lab_mrkr_ClassOfWarrantOrRightOutStandingIntrinsicValue" xml:lang="en-US">Total Intrinsic Value</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ClassOfWarrantOrRightOutStandingIntrinsicValue" xlink:to="lab_mrkr_ClassOfWarrantOrRightOutStandingIntrinsicValue" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ClassOfWarrantOrRightOutStandingIntrinsicValue" xml:lang="en-US">Intrinsic value of outstanding class of warrant or right.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageExercisePrice" xlink:label="loc_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageExercisePrice" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageExercisePrice" xml:lang="en-US">Class Of Warrant Or Rights Out Standing Weighted Average Exercise Price</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageExercisePrice" xml:lang="en-US">Weighted Average Exercise Price, Beginning Balance</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageExercisePrice" xml:lang="en-US">Weighted Average Exercise Price, Ending Balance</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageExercisePrice" xlink:to="lab_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageExercisePrice" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ClassOfWarrantOrRightsOutStandingWeightedAverageExercisePrice" xml:lang="en-US">Class Of Warrant Or Rights Outstanding Weighted Average Exercise Price.</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_NumberOfWarrantsCashlessExercised" xlink:label="loc_mrkr_NumberOfWarrantsCashlessExercised" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_NumberOfWarrantsCashlessExercised" xml:lang="en-US">Number Of Warrants Cashless Exercised</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_mrkr_NumberOfWarrantsCashlessExercised" xml:lang="en-US">Number of Warrant of Cashless exercised</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_NumberOfWarrantsCashlessExercised" xlink:to="lab_mrkr_NumberOfWarrantsCashlessExercised" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_NumberOfWarrantsCashlessExercised" xml:lang="en-US">Number of warrants cashless exercised.</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EquityAbstract" xml:lang="en-US">Equity [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquityAbstract" xlink:to="lab_us-gaap_EquityAbstract" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_CommonStockCapitalSharesReservedForFutureIssuanceTable" xlink:label="loc_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceTable" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceTable" xml:lang="en-US">Common Stock Capital Shares Reserved For Future Issuance [Table]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceTable" xml:lang="en-US">Common Stock Capital Shares Reserved For Future Issuance [Table]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceTable" xlink:to="lab_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceTable" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceTable" xml:lang="en-US">Common Stock Capital Shares Reserved For Future Issuance [Table]</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TitleOfIndividualAxis" xlink:label="loc_us-gaap_TitleOfIndividualAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TitleOfIndividualAxis" xml:lang="en-US">Title of Individual [Axis]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_TitleOfIndividualAxis" xml:lang="en-US">Title of Individual [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TitleOfIndividualAxis" xlink:to="lab_us-gaap_TitleOfIndividualAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" xml:lang="en-US">Relationship to Entity [Domain]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" xml:lang="en-US">Relationship to Entity [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" xlink:to="lab_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="loc_us-gaap_TypeOfArrangementAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TypeOfArrangementAxis" xml:lang="en-US">Type of Arrangement and Non-arrangement Transactions [Axis]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_TypeOfArrangementAxis" xml:lang="en-US">Type of Arrangement and Non-arrangement Transactions [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TypeOfArrangementAxis" xlink:to="lab_us-gaap_TypeOfArrangementAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ArrangementsAndNonarrangementTransactionsMember" xml:lang="en-US">Arrangements and Non-arrangement Transactions [Domain]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ArrangementsAndNonarrangementTransactionsMember" xml:lang="en-US">Arrangements and Non-arrangement Transactions [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:to="lab_us-gaap_ArrangementsAndNonarrangementTransactionsMember" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ExerciseOfStockWarrantsMember" xlink:label="loc_mrkr_ExerciseOfStockWarrantsMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ExerciseOfStockWarrantsMember" xml:lang="en-US">Exercise Of Stock Warrants [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ExerciseOfStockWarrantsMember" xlink:to="lab_mrkr_ExerciseOfStockWarrantsMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeStatementLocationAxis" xml:lang="en-US">Income Statement Location [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementLocationAxis" xlink:to="lab_us-gaap_IncomeStatementLocationAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeStatementLocationDomain" xml:lang="en-US">Income Statement Location [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementLocationDomain" xlink:to="lab_us-gaap_IncomeStatementLocationDomain" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongtermDebtTypeAxis" xml:lang="en-US">Long-term Debt, Type [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongtermDebtTypeAxis" xlink:to="lab_us-gaap_LongtermDebtTypeAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongtermDebtTypeDomain" xml:lang="en-US">Long-term Debt, Type [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongtermDebtTypeDomain" xlink:to="lab_us-gaap_LongtermDebtTypeDomain" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ClassOfWarrantOrRightExerciseAxis" xlink:label="loc_mrkr_ClassOfWarrantOrRightExerciseAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ClassOfWarrantOrRightExerciseAxis" xml:lang="en-US">Class of Warrant or Right, Exercise [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ClassOfWarrantOrRightExerciseAxis" xlink:to="lab_mrkr_ClassOfWarrantOrRightExerciseAxis" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ClassOfWarrantOrRightExerciseDomain" xlink:label="loc_mrkr_ClassOfWarrantOrRightExerciseDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ClassOfWarrantOrRightExerciseDomain" xml:lang="en-US">Class of Warrant or Right, Exercise [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ClassOfWarrantOrRightExerciseDomain" xlink:to="lab_mrkr_ClassOfWarrantOrRightExerciseDomain" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_CommonStockCapitalSharesReservedForFutureIssuanceLineItems" xlink:label="loc_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceLineItems" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceLineItems" xml:lang="en-US">Common Stock Capital Shares Reserved For Future Issuance [Line Items]</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceLineItems" xml:lang="en-US">Common Stock Capital Shares Reserved For Future Issuance [Line Items]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceLineItems" xlink:to="lab_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceLineItems" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_CommonStockCapitalSharesReservedForFutureIssuanceLineItems" xml:lang="en-US">Common Stock Capital Shares Reserved For Future Issuance [Line Items]</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xml:lang="en-US">Stock Issued During Period, Shares, New Issues</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="loc_us-gaap_SharesIssuedPricePerShare" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SharesIssuedPricePerShare" xml:lang="en-US">Shares Issued, Price Per Share</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharesIssuedPricePerShare" xlink:to="lab_us-gaap_SharesIssuedPricePerShare" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" xml:lang="en-US">Stock Issued During Period, Value, New Issues</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:to="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xml:lang="en-US">Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:label="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xml:lang="en-US">Class of Warrant or Right, Number of Securities Called by Warrants or Rights</label>
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xml:lang="en-US">Class of warrant or right, number of securities called by warrants or rights | shares</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:to="lab_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpense" xml:lang="en-US">Allocated Share-based Compensation Expense</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllocatedShareBasedCompensationExpense" xlink:to="lab_us-gaap_AllocatedShareBasedCompensationExpense" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SellingGeneralAndAdministrativeExpense" xml:lang="en-US">Selling, General and Administrative Expense</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SellingGeneralAndAdministrativeExpense" xlink:to="lab_us-gaap_SellingGeneralAndAdministrativeExpense" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" xml:lang="en-US">Stock Issued During Period, Shares, Issued for Services</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FinancialInstrumentAxis" xlink:label="loc_us-gaap_FinancialInstrumentAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FinancialInstrumentAxis" xml:lang="en-US">Financial Instrument [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialInstrumentAxis" xlink:to="lab_us-gaap_FinancialInstrumentAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xml:lang="en-US">Financial Instruments [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" />
<loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_LegalEntityAxis" xlink:label="loc_dei_LegalEntityAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_LegalEntityAxis" xml:lang="en-US">Legal Entity [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_LegalEntityAxis" xlink:to="lab_dei_LegalEntityAxis" />
<loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityDomain" xlink:label="loc_dei_EntityDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityDomain" xml:lang="en-US">Entity [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityDomain" xlink:to="lab_dei_EntityDomain" />
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_EasternCapitalLimitedMember" xlink:label="loc_mrkr_EasternCapitalLimitedMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_EasternCapitalLimitedMember" xml:lang="en-US">Eastern Capital Limited [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_EasternCapitalLimitedMember" xlink:to="lab_mrkr_EasternCapitalLimitedMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_EasternCapitalLimitedMember" xml:lang="en-US">EasternCapitalLimitedMember</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ArrangementsAxis" xlink:label="loc_mrkr_ArrangementsAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ArrangementsAxis" xml:lang="en-US">Arrangements [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ArrangementsAxis" xlink:to="lab_mrkr_ArrangementsAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ArrangementsAxis" xml:lang="en-US">Arrangements Axis</label>
<loc xlink:type="locator" xlink:href="mrkr-20180930.xsd#mrkr_ArrangementsDomain" xlink:label="loc_mrkr_ArrangementsDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ArrangementsDomain" xml:lang="en-US">Arrangements [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ArrangementsDomain" xlink:to="lab_mrkr_ArrangementsDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ArrangementsDomain" xml:lang="en-US">Arrangements</label>
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_mrkr_ConsultingArrangementsMember" xml:lang="en-US">Consulting Arrangements [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mrkr_ConsultingArrangementsMember" xlink:to="lab_mrkr_ConsultingArrangementsMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_mrkr_ConsultingArrangementsMember" xml:lang="en-US">Consulting Arrangements</label>
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xml:lang="en-US">Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table]</label>
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<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationAbstract" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationAbstract" xml:lang="en-US">Share-based Compensation [Abstract]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationAbstract" xlink:to="lab_us-gaap_ShareBasedCompensationAbstract" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseMember" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpenseMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpenseMember" xml:lang="en-US">Research and Development Expense [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ResearchAndDevelopmentExpenseMember" xlink:to="lab_us-gaap_ResearchAndDevelopmentExpenseMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GeneralAndAdministrativeExpenseMember" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GeneralAndAdministrativeExpenseMember" xml:lang="en-US">General and Administrative Expense [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GeneralAndAdministrativeExpenseMember" xlink:to="lab_us-gaap_GeneralAndAdministrativeExpenseMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xml:lang="en-US">Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized</label>
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<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xml:lang="en-US">Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AwardTypeAxis" xml:lang="en-US">Award Type [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AwardTypeAxis" xlink:to="lab_us-gaap_AwardTypeAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xml:lang="en-US">Equity Award [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PlanNameAxis" xml:lang="en-US">Plan Name [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanNameAxis" xlink:to="lab_us-gaap_PlanNameAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PlanNameDomain" xml:lang="en-US">Plan Name [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanNameDomain" xlink:to="lab_us-gaap_PlanNameDomain" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xml:lang="en-US">Adjustments for New Accounting Pronouncements [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:to="lab_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TypeOfAdoptionMember" xml:lang="en-US">Type of Adoption [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TypeOfAdoptionMember" xlink:to="lab_us-gaap_TypeOfAdoptionMember" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingStandardsUpdate201409Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201409Member" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccountingStandardsUpdate201409Member" xml:lang="en-US">Accounting Standards Update 2014-09 [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingStandardsUpdate201409Member" xlink:to="lab_us-gaap_AccountingStandardsUpdate201409Member" />
<loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xml:lang="en-US">Class of Warrant or Right, Exercise Price of Warrants or Rights</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:to="lab_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" />
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xml:lang="en-US">Related Party [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" />
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RelatedPartyDomain" xml:lang="en-US">Related Party [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyDomain" xlink:to="lab_us-gaap_RelatedPartyDomain" />
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_OwnershipAxis" xml:lang="en-US">Ownership [Axis]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_OwnershipAxis" xlink:to="lab_srt_OwnershipAxis" />
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<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_OwnershipDomain" xml:lang="en-US">Ownership [Domain]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_OwnershipDomain" xlink:to="lab_srt_OwnershipDomain" />
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