It has also been reported that a number of tumor tissues and cell lines express purine receptors belonging to the P1 and P2 receptor families, which are prevailingly activated by their natural ligands that are ATP or ADO, or by synthetic analogs, leading to a variety of effects ranging from tumor cells proliferation to increase in cell migration and aggressiveness, modification of tumor cell metabolism and ability of immune attack evasion (reviewed by [22]). The gene discussed is ADO; the disease is neoplasm.