BLL-1

BLL-1 is a small molecule inhibitor of Protein Arginine Methyltransferase 5 (PRMT5), identified from a small molecule library by researchers at The Ohio State University. PRMT5 is a type II arginine methyltransferase that catalyzes the transfer of methyl groups to arginine residues, specifically methylating histone H3 at arginine 8 (H3R8) and H4 at arginine 3 (H4R3), which leads to the silencing of tumor suppressor genes. BLL-1 specifically blocks the symmetric dimethylation of H4R3 (H4R3me2s). In preclinical studies involving malignant melanoma cell lines, treatment with BLL-1 resulted in a reduction of H4R3me2s levels, decreased cell proliferation, and significantly increased apoptosis. It also appears to restore the expression of immunomodulatory genes like the CXCL10 chemokine.