TGFB1 and melanoma: TGF-β signaling can function in an autocrine and paracrine manner in melanoma to drive invasiveness and metastasis formation (Daroqui et al., 2012; Tuncer et al., 2019) and TGF-β ligands were described to initiate and regulate their own expression through a positive feedback loop (Perrot, Javelaud and Mauviel, 2013).