C4B and central nervous system cancer: The anti-tumor response process of microglia under glioma activation was reconstructed, which showed a series of gene changes involved in the activation process of microglia (Figures 5A–C, Supplementary Figure S4A): including the enhancement of MHC-II gene expression (H2-Aa, H2-Ab1, H2-Eb1, Cd74, and B2m), activation of the IFN pathway (Ifitm3, Ifi27I2a, Ifit2, and Ifit3), activation of the complement system (C4b), and the weakening of inhibitors of the NFkB pathway (Nfkb1, Nfkbia, Nfkbiz, and Tnfaip3).