The adenosine-A3 receptor (A3AR) belongs to a family of four GPCRs (A1, A2A, A2B, and A3) (Fredholm et al., 2011) that respond to adenosine and are attractive drug targets for a number of pathophysiologic conditions including cancer, ischemia, cardiovascular disease, and inflammation. The gene discussed is ADORA3; the disease is cancer.