TGFB1 and neoplasm: Particularly, GAMs are forced to switch to the M2 phenotypes in the GBM microenvironment, secreting factors such as IL-10, IL-4, IL-6, macrophage colony-stimulating factor, TGF-β, macrophage inhibitory factor, and prostaglandin E2, which, due to their anti-inflammatory action, facilitate tumoral immune-escape and increase tumor invasiveness, angiogenesis and growth, contributing to the creation of an immunosuppressive tumoral microenvironment [38].