IFNG and cancer: One potential therapeutic use of such method is the knock-out of inhibitory checkpoint gene PD-1 (programmed death-1), an inhibitor of T-cell activity that is stimulated by dendritic cells and cancer cells through PD-L1 (PD-1 ligand), which upregulates the T-cell cytotoxicity and interferon-gamma (IFN-γ) production giving the possibility of a novel strategy for anti-tumoral immunotherapy (22).