Figure 7

Schematic showing the TGFβ/LIF- mediated tumor suppressive role in melanoma. Our results show that TGFβ activates its canonical Smad signaling pathway, which in turn induces LIF secretion. LIF, via phosphorylating STAT3, triggers LIF binding to the p21 promoter, which consequently induces p21 gene expression, which elicits its inhibitory effect on cell cycle progression. Moreover, p21 induces apoptosis in a Caspase3/7 dependent manner. On the other hand, TGFβ-mediated activation of LIF inhibits migratory behavior in melanoma cell lines. Taken together, these results show the TGFβ/LIF-mediated tumor suppressive role in melanoma.