Tazemetostat is a potent and highly selective EZH2 inhibitor with sustained safe anticancer effects in in vitro and in vivo models of mutant B-cell non-Hodgkin's lymphoma, INI1-negative malignant rhabdomyosarcoma, and SMARCA4-negative malignant ovarian rhabdomyosarcoma, and phase 2 clinical studies with Tazemetostat monotherapy in adult B-cell non-Hodgkin's lymphoma are ongoing [24]. Here, SMARCA4 is linked to rhabdomyosarcoma.