TNF and cancer: Moreover, EMT is divided into 3 distinct subtypes: type 1 EMT is related to morphogenesis and is modulated by signaling pathways such as WNT/β-catenin, which in turn regulates Snail1 expression (132); type 2 EMT is related to wound healing and fibrosis and can be regulated by Slug, epidermal growth factor (EGF) and transforming growth factor β (TGF-β) pathways (130); and type 3 EMT occurs in cancer cells, playing an important role on tumor invasion and metastasis (133), and can be regulated by cytokines secreted in the tumoral niche such as TGF-β and tumor necrosis factor α (TNFα) (5).