Recently, IL-15 produced in the hepatic microenvironment is revealed to downregulate FOXO1 in CD8+ T cells, enabling them to acquire a resident character by upregulating CXCR6, thus making CXCR6+PD1+CD8+ T cells to be capable of eliciting auto-aggressive killing of liver cells to trigger MASH and the transition to HCC [13]. The gene discussed is CXCR6; the disease is hepatocellular carcinoma.