JQ1 (+/-)

JQ1 is a potent BET bromodomain inhibitor. IC50 = 17.7, 32.6, 76.9 and 12942 nM respectively for BRD2 (N-terminal (N) ), BRD4 (C-terminal (C) ), BRD4 (N) and CREBBP respectively. Competitive binding by JQ1 displaces the BRD4 fusion oncoprotein from chromatin, prompting squamous differentiation and specific antiproliferative effects in BRD4-dependent cell lines and patient-derived xenograft models establishing proof-of-concept for targeting protein-protein interactions of epigenetic readers1.