CCL2 and central nervous system cancer: In addition and consistent with emerging descriptions of activated myeloid cell signatures in the glioma microenvironment, we also observed a population of glioma-associated microglia107,109,110 (microglia 2 (cluster 2)) that express Ccl2, Ccl12, Ifitm3, and Il1β (Fig. 10e and Supplementary Fig. 8a, b, e) and when compared to the other microglial populations show enrichment for the pro-inflammatory cytokine osteopontin, Spp1, and the lipid metabolism gene, Apoe (Fig. 10e or Supplementary Fig. 8a, b, e).