To gain insights into the underlying immune mechanism, we further explored the associations between our signature and seven promising immune checkpoints of ICC, including PD-1, PD-L1, CTLA-4, CD40, HHLA2, TGFB1, and CMTM6 (1, 30–33). This evidence concerns the gene TGFB1 and intrahepatic cholangiocarcinoma.