Tumor cells and other cells in the tumor microenvironment secrete cytokines such as IL-6 [57], indolamine-2,3-dioxygenase [58], vascular endothelial growth factor [59], programmed death-1 ligand [60], and soluble Fas ligand [61], which hamper antitumor immunity and promote tumor growth. Here, FASLG is linked to neoplasm.