Biochem/physiol Actions

UNC3866 inhibits the CBX chromodomains of the Polycomb repressive complex 1 (PRC1), which is involved in transcriptional repression. UNC3866 selectively targets CBX4 and CBX7 most potently, with Kd values of ~100 nM. The PRC1 chromodomains facilitate PRC1-mediated transcriptional repression by targeting the complex to Trimethyllysine 27 on histone 3 (H3K27me3). UNC3866 antagonizes the methyllysine (Kme) reading function, and has been shown to inhibit the PC3 prostate cancer cell proliferation associated with CBX7 overexpression.

Antagonist of chromodomains CBX4/7 of Polycomb repressive complex 1