CTS3353

CTS3353 is a novel small-molecule degrader of the Polycomb Repressive Complex 2 (PRC2), developed by CytosinLab Therapeutics. It is designed to target both the canonical histone methyltransferase activity and the non-canonical, non-enzymatic functions of PRC2, which are often implicated in tumor maintenance and progression. Unlike traditional enzymatic inhibitors or conventional PROTAC-based degraders, CTS3353 achieves PRC2 downregulation through complex disruption, offering improved cell permeability and metabolic stability. Preclinical data presented at AACR 2026 demonstrated its efficacy in models of metastatic castration-resistant prostate cancer (mCRPC), diffuse large B-cell lymphoma (DLBCL), and triple-negative breast cancer (TNBC), showing robust antitumor activity and survival benefits without significant systemic toxicity.