Following 24-hour co-culture with Tregs, we observed increased CCL2 mRNA expression in each of four canine glioma cell lines (GSC0514: 0.95 ± 0.17- fold increased, 4A p < 0.001; J3T-Bg: 1.02 ± 0.33, Fig. 4B p < 0.05; GSC1110: 0.55 ± 0.11, Fig. 4C p < 0.1; and G06A: 0.56 ± 0.19-fold increase, Fig. 4D p < 0.05). Here, CCL2 is linked to central nervous system cancer.