PD-L1 has a conserved cytoplasmic sequence that is important for apoptotic resistance to both type I and type II interferon cytotoxicity.51 Additionally, human cancer samples that acquire enhancing mutations within this region have been shown to have increased resistance to pro-apoptotic signaling of interferons.52 Thus, the ability of IPAG to prevent PD-L1 from progressing through the secretory pathway and reaching the cell surface would have a detrimental effect on cancer cell survival in the presence of sustained IFN-γ signaling. This evidence concerns the gene IFNG and cancer.