Several epigenetic inhibitors are currently under clinical evaluation for cancer treatment, among which inhibitors of histone deacetylases (HDACs), enhancer of Zeste homolog 2 (EZH2), DNA methyltransferases (DNMTs), lysine-specific demethylase 1 (LSD1), and bromodomain and extra-terminal domain (BET) family proteins [11, 12]. The gene discussed is EZH2; the disease is cancer.