CSF1 and its receptor CSF-1R support proliferation and survival of mononuclear phagocytes through the DAP12-β-catenin axis, which controls the expression of survival genes.34 We explored if tumour-derived CSF2 is important for survival of infiltrating microglia and macrophages by double staining of the glioma-bearing brain sections for Iba1 and TUNEL (Terminal dUTP nick-end labelling of DNA) that allows to identify DNA fragmentation and stains apoptotic cells. The gene discussed is AIF1; the disease is central nervous system cancer.