CD8A and cancer: Even though targeting glutamine metabolism has shown a modest effect globally in vivo25,26, Leone et al. have recently shown that glutamine metabolism inhibition using an analog of the broad spectrum inhibitor 6-diazo-5-oxo-L-norleucine (DON) can enhance immune checkpoint inhibitor efficiency due to glutaminolysis blockade, which can be compensated for in CD8+ T cells but not in cancer cells27.