Cytokines secreted by glioma can activate the STAT3 signaling in macrophages, down-regulate the surface antigens required for the antigen presentation, and up-regulate M2 macrophages-specific antigens like epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), and matrix metallopeptidase (MMPs), which in turn promote the tumor growth and invasion (29–31). Here, EGF is linked to central nervous system cancer.