NT5E and neoplasm: CD73 plays an essential role in tumor-mediated immune evasion due to the enzymatic conversion of extracellular adenosine monophosphate into adenosine, a metabolite which inhibits T-cell activation, proliferation and cytokine production, therefore blunting antitumor immune responses, while also promoting angiogenesis, enhancing tumor cell adaptation to hypoxia and facilitating resistance to cellular stress.