Interestingly, αPD-1 treatment has been shown to enhance mitochondrial respiration in CD8 T cells in certain tumor models,31 which is consistent with the findings that PD-1 signaling blocks PGC-1α expression and mitochondrial activity.21 However, enforcing PGC-1α expression in CD8 T cells only tended to have an additive effect with checkpoint blockade to boost antitumor immunity. This evidence concerns the gene PPARGC1A and neoplasm.