Chaetocin is an inhibitor of histone methyltransferases (HMTs) including SUV39H1 and Lys9-specific HMTs such as G9a. It also has some inhibitory effects on SET7, EZH2, and SET7/9. Chaetocin can also induce cellular oxidative stress, selectively killing cancer cells and rapidly-proliferating primary cells. It is a fungal myotoxin. The inhibitor is useful in epigenetics and cancer research.