We found that relative to CCR2+HSC-derived cells, once in the brain tumor, cells that arose from CCR2−HSCs expressed significantly more CCR2 (p = 0.0035), F4/80 (p = 0.0138), and Ly6G/6C (p = 0.0001) (Supplementary Fig. 1). Here, CCR2 is linked to brain neoplasm.