NT5C2 and cancer: Cytosolic 5′-nucleotidase II (NT5C2) functions in dephosphorylating nucleoside triphosphates and is able to deactivate Ara-C through the de-phosphorylation of Ara-C monophosphate to Ara-C, and an increase in NT5C2 expression has shown to associate with the development of resistance to nucleoside analog-based chemotherapies, such as Ara-C, gemcitabine, and cladribine, in different cancer cell lines [18, 19].