Moreover, GAMs have been identified as a major source of CCL2 in glioblastoma multiforme.39 Rodent models have demonstrated that GAM-derived CCL2 is necessary for tumoral infiltration of T-regulatory cells.39 Therefore, it is plausible that canine GAMs are also a source of CCL2 within canine astrocytomas, similar to human astrocytomas. This evidence concerns the gene CCL2 and astrocytoma (excluding glioblastoma).