In fact, interleukin 15 (IL15) produced in the hepatic microenvironment downregulates forkhead box O1 (FOXO1) in CD8 T cells, enabling them to acquire a resident character by upregulating CXCR6, leading to steatohepatitis (MASH), fibrosis, and facilitating HCC development [88]. Here, FOXO1 is linked to metabolic dysfunction-associated steatohepatitis.