M1 and M2 play opposite roles, while M1 plays anti-tumor effects, M2 phenotype has an immunosuppressive effect and secretes TGF-B, IL-6, IL-1B, EGF, and other cytokines to promote the growth, invasion, and expansion of gliomas by stimulating tumor-related blood vessel formation and tumor metastasis. This evidence concerns the gene TGFB1 and central nervous system cancer.