PMN-MDSCs (11) expressed more Cxcl2 and less Cxcl3 in early than late GBM, and expression of their receptor Cxcr2 is highest in neutrophil (25) (Fig. 6c), perhaps reflecting a switch in Cxcr2 ligand use during GBM progression. Here, CXCL2 is linked to glioblastoma.