Insights into the Transforming Growth Factor-β Signaling Pathway in Cutaneous Melanoma

Transforming growth factor-beta (TGF-beta) is a pleiotropic growth factor with broad tissue distribution that plays critical roles during embryonic development, normal tissue homeostasis, and cancer. While its cytostatic activity on normal epithelial cells initially defined TGF-beta signaling as a tumor suppressor pathway, there is ample evidence indicating that TGF-beta is a potent pro-tumorigenic agent, acting via autocrine and paracrine mechanisms to promote peri-tumoral angiogenesis, together with tumor cell migration, immune escape, and dissemination to metastatic sites. This review summarizes the current knowledge on the implication of TGF-beta signaling in melanoma.