TGFB1 and cancer: TGF-β also enhances the pro-tumoral immune response by promoting the function of regulatory T cells (Tregs) (which also secrete TGF-β), facilitating the conversion of normal fibroblasts into cancer-associated fibroblasts (CAFs), and polarizing macrophages and neutrophils to an M2/N2 (i.e., tumor-promoting) phenotype [47,48,49].