[5], [6] Overexpression and hyperactivity of EZH2 have been implicated in the pathogenesis of several cancer types, including prostate, [7], [8] breast, and endometrial carcinomas, as well as melanoma. [9] The discovery that EZH2 is a mutant oncogene in germinal center-phenotype B cell lymphomas raises the possibility of targeting this pathway pharmacologically in the treatment of patients with these lymphomas. The gene discussed is EZH2; the disease is B-cell non-Hodgkin lymphoma.