CBP/p300 bromodomain inhibitor OPN-6602

An orally bioavailable small molecule inhibitor of the bromodomain of the histone acetyltransferase (HAT) paralogs, CREB binding protein (CBP) and p300 (E1A-associated protein p300; EP300; p300 HAT), with potential antineoplastic activity. Upon oral administration, CBP/p300 bromodomain inhibitor OPN-6602 targets and binds to the bromodomains of p300 and CBP. This disrupts the acetylation of histones and other proteins, prevents the co-activation of key transcription factors that contribute to tumor progression including the androgen receptor (AR), interferon regulatory factor 4 (IRF4) and Myc proto-oncogene protein (c-Myc), and downregulates AR and IRF4/MYC signaling, thereby inhibiting tumor cell proliferation. The HAT paralogs p300 and CBP are key transcriptional co-activators that are essential for a multitude of cellular processes and are implicated in the progression and therapeutic resistance of certain cancers.