CCL2 and glioblastoma: Following the migration protocols for 20 days, we validated the chemotactic effect of MCP-1/CCL2 and SDF-1/CXCL12 in mediating the migration of MSCs toward CD133+ GBM cells, and we observed tumor development, glial invasiveness, vascular proliferation and detection of a high number of cycling cells, when compared to the study situation that did not receive MSCs.