Schwann cells are the main source of CXCR3 ligands in the PNS via two main pathways: (1) similar to glioma, type-I IFN promotes CXCL10 expression in Schwann cells [35], and (2) activation of the Ras/Raf/MEK/ERK pathway also promotes the expression of CXCL10 in Schwann cells [35], and NF-1 as an inhibitor of Ras protein can inhibit this pathway and suppress the expression of CXCL10 in Schwann cells [35]. The gene discussed is CXCL10; the disease is central nervous system cancer.