The differential regulation of multiple metabolic pathways, including bile acid metabolism, mTORC1, and glycolysis (Figure 3D), may reflect the fact that the CD8+ TIL cells are hosted in a hypoxic, acidic, and nutrient-depleted TME where the cellular metabolism has been reprogrammed as an adaptive mechanism to facilitate their proliferation and survival in melanoma. The gene discussed is CD8A; the disease is melanoma.