BRD4 Inhibitor-15 (compound 13) is a highly potent and specific BRD4 inhibitor with an IC50 of 18 nM, inducing apoptosis in 22RV1 cells by regulating Bcl-2/Bax proteins and activating caspase-3 signaling, and down-regulating c-Myc levels, making it valuable for prostate cancer research [1].