IDO1 and glioblastoma: To explore the immune status of the infiltrated macrophages in GBM, we evaluated the differential expression of seven immunostimulatory GAM-related genes (TLR-4, IFNG, IL1B, TNF, NF2, CD80, and CD86) and seven immunosuppressive GAM-related genes (IDO, IL10, TGFB1, CCL2, CCL5, CD163, and MSR1) in patients with LGG and GBM and the relationships of these genes with survival in TCGA database (Fig. 1A, B).