TGFB1 and male reproductive organ cancer: Studies focused on understanding the effects of systemic TGF-β inhibition on early stages of prostate tumorigenesis have used trivalent TGF-β receptor trap (RER) comprised of domains from the TGF-β II and III receptors to completely block (a) TGF-β II binding and (b) TGF-β1 and TGF-β3 signaling in cultured PCa cells.