CD69 and intrahepatic cholangiocarcinoma: Existing research has suggested the positive relationships between PD-L1 (programmed cell death ligand 1) expression, CD8+ tumor-infiltrating lymphocytes (TILs) infiltration, T cell inflammatory gene feature expression and estimated CD8 + TIL abundance in ICC tumor cells, while the characteristic genes of Wnt/β-catenin and TGF-β signaling pathways are enriched in tumors with a low proportion of CD69+ CD103+ tissue-resident memory-like CD8+ TIL.