TGFB1 and neoplasm: Under the influence of tumor-derived factors, TAMs could also secrete an array of cytokines, including IL-10, transforming growth factor-β (TGF-β) and prostaglandin-E2 (PGE2), that further inhibit T cell-mediated immune response to establish a self-propagating immunosuppressive TME [8, 23, 27].