Since these pathways play an important role in regulating the G1/S checkpoint of normal melanocytes and are major regulators of melanocyte transformation [51,52], the upregulation of miRNAs controlling TP53/RB1 activation and TGFβ/SMAD signaling pathways may contribute to G1/S checkpoint abnormalities that are frequently observed during melanoma progression. This evidence concerns the gene TGFB1 and melanoma.