TGFB1 and neoplasm: TGF-β can inhibit the cytotoxic proliferation, differentiation or immune activity of T lymphocytes and NK cells, while TGF-β can also convert the cytotoxic effect of NK cells into a secretory effect, and secretory effector NK cells are able to produce a series of cytokines, such as vascular endothelial growth factor (VEGF) and IL-8 to promote tumor growth and angiogenesis.[22]