Figure 1.
The ligand-induced transactivation of AR is enhanced by treatment with TGF-β. (A) CAT assays were performed with extracts from DU145 cells transfected with AR expression vector (pSG5-AR) (1 μg) in the presence (+) or absence (−) of DHT (10−8 M) or TGF-β1 (10 ng/ml) or specific TGF-β1 neutralizing antibody (20 mg/ml). (B) (Left) PC-3 cells were transfected with pSG5-AR (1 μg) in the presence (+) or absence (−) of DHT (10−8 M) with increasing amounts of TGF-β1. (Right) A fixed amount of TGF-β1 (10 ng/ml) was added to transfected PC-3 cells with increasing amounts of specific TGF-β1 neutralizing antibody. (C) PC-3(AR)2 cells stably transfected with AR were overexpressed with TGF-β type I (TβRI) or type II (TβRII) receptor or constitutively active TGF-β type I receptor (TβRI-T204D) as indicated. Three micrograms of MMTV-CAT or MMTV-Luc was used as a reporter plasmid in all experiments. All values represent the averages ± SD of four independent experiments.