Transforming growth factor-β1 (TGF-β1) induces mesenchymal fibroblasts to differentiate into myofibroblasts and regulates the response of epithelial cells to the IGF-1-mediated mesenchymal–epithelial cell axis [32], leading to hyperplasia associated with BPH. This evidence concerns the gene TGFB1 and benign prostatic hyperplasia.