BRD4 and Familial prostate cancer: Furthermore, we previously reported that androgen signaling in prostate cancer requires BET protein activity (17) and identified a BRD4 binding site in the TMPRSS2 and ACE2 genes (SI Appendix, Fig. S8); thus, we examined whether pulmonary AR, Tmprss2, and Ace2 levels were responsive to systemic treatment with BET inhibitor JQ1 in male mice.