CCL2 and glioma: Immunoregulatory cytokines such as pro-inflammatory factors (IL-1, IL-2, TNF-α, IFN-γ), anti-inflammatory factors (IL-10, TGF-β), and chemokines (CCL-2, CCL-5, CCL-7, CX3CL1) are synthesized and secreted in the microenvironment of glioma.