The action of TGF-β in prostate cancer metastasis is multilayered and complex, as this cytokine serves functionally opposing roles: as a master regulator of EMT within the tumor microenvironment, conferring tumor cell invasion and migration, while the loss of TGF-β signaling in prostate cancer in transgenic mouse models accelerated progression and metastasis to advanced disease [30,126]. This evidence concerns the gene TGFB1 and prostate cancer.