CSF-1R tyrosine kinase inhibitors that block the CSF-1 signaling pathway have shown good therapeutic effects in preclinical models of various tumors, including acute myeloid leukemia, malignant melanoma, and malignant glioma (88, 89), and CSF-1R inhibitor RG7155 significantly reduced the macrophage infiltration in a case of sarcoma with high CSF-1 expression (90). Here, CSF1 is linked to malignant glioma.