EZH2: Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase that catalyzes the methylation of histone3 lysine 27 (H3K27) and plays an important role in stem cell pluripotency and germline development. EZH2 gain-of-function mutations occur in 22% of germinal center B cell diffuse large B cell lymphoma (GCB-DLBCL) and 7-12% of follicular lymphoma (FL). Dysregulation of EZH2 activity is also found in a set of genetically defined solid tumors that include malignant rhabdoid tumors, synovial sarcomas and ovarian cancers. EBI-2554, an oral EZH2 selective inhibitor, is currently in clinical development in China.