FN1 and renal fibrosis: Tamoxifen has been less extensively studied in urethral stricture disease, but its antifibrotic activity appears to involve downregulation of TGF-β and modulation of collagen metabolism, as demonstrated in renal fibrosis models - where it reduced collagen I/III, fibronectin, and TGF-β1 expression, and inhibited fibroblast proliferation [24].