Extended Data Fig. 6: BD2-dependent BRD4–AR interaction.

a, LNCaP cells were treated for 16 h with DHT in the presence of vehicle, ABBV-744 (90 nM) or ABBV-075 (60 nM) with or without trichostatin A (TSA) (0.5 μg ml⁻¹). AR immunoprecipitation (IP) using nuclear extracts pulled down BRD4 in trichostatin-A- and DHT-treated samples. ABBV-744 and ABBV-075 blocked BRD4 co-immunoprecipitation with AR. Fold change values from densitometry analysis are listed below the BRD4 blot, in which a 1.9-fold increase in the AR:BRD4 immunocomplex was measured in the trichostatin-A- and vehicle-treated lane compared with 0.87 or 0.88 after treatment with ABBV-744 or ABBV-075, respectively. Western blot of 2% immunoprecipitation input revealed no change in nuclear protein levels after inhibitor treatment. b, LNCaP cells were treated for 16 h with DHT in the presence of vehicle, ABBV-744 (90 nM) or ABBV-075 (60 nM). CDK9 or BRD4 immunoprecipitation using nuclear extracts pulled down BRD4 or GATA2, which is not blocked by treatment with ABBV-744. c, LNCaP cells were treated for 16 h with DHT in the presence of vehicle, ABBV-744 (90 nM) or ABBV-075 (60 nM). CDK9 or cyclin T1 immunoprecipitation using nuclear extracts pulled down HEXIM1, which is not blocked or enhanced by treatment with ABBV-744. d, Alignment of a KXXK motif in H4, AR and the lack of this motif in AR-V7. e, Cooperative interaction of BD1 and BD2 of BRD4 with acetylated AR at BRD4–AR co-occupied super-enhancers may underlie sensitivity to ABBV-744. a–c, Results are representative of n > 2 independent experiments. For a–c gel source data, see Supplementary Fig. 2.