WY332

WY332 is a novel small molecule inhibitor designed to target the Ring1B-Bmi1 complex, which serves as the enzymatic core of the Polycomb Repressive Complex 1 (PRC1). Developed by researchers at the University of Michigan, WY332 was identified through NMR fragment-based screening and medicinal chemistry optimization. It binds to the Ring1B-Bmi1 interface with low micromolar affinity, effectively blocking its E3 ubiquitin ligase activity. This inhibition leads to a selective reduction in histone H2A lysine 119 ubiquitination (H2AK119ub), a key epigenetic modification associated with gene silencing in leukemia stem cells (LSCs). Preclinical studies have demonstrated that WY332 can impair the self-renewal capacity of LSCs, induce differentiation in leukemic cells (as evidenced by changes in CD11b and CD34 expression), and alter the expression of genes typically suppressed in LSCs, suggesting potential therapeutic utility in treating acute myeloid leukemia (AML).