CCL2 and glioma: Higher level of MCP-1 expression seen in GBM compared to the lower grade of glioma, and expression of MCP-1 by tumor cells is believed to stimulate the recruitment of macrophages that could actuate angiogenesis and edema, two histopathological highlights of GBM (Desbaillets et al., 1994 ▶; Platten et al., 2003 ▶; Salcedo et al., 2000 ▶).