CSF1R and central nervous system cancer: TAM-targeting agents like CSF-1 receptor (CSF-1R) inhibitor have shown promise by reprogramming M2-TAMs toward an anti-tumorigenic ‘M1’ phenotype in murine glioma models, yet clinical trials on GBM patients showed poor response and patients acquired resistance by the tumor microenvironment (Pyonteck et al., 2013).