It has been found that the hypoxic conditions of tumor microenvironment results in increased extracellular expression of both ectonucleotidase enzymes i.e., CD39 and CD73, ultimately increases the production of adenosine.9 In tumor microenvironment, the overexpressed adenosine plays an important role in tumor immunoescape mechanism regardless of other immune modulating factors. This evidence concerns the gene ENTPD1 and neoplasm.