Thus, different molecules are under investigation in clinic: anti-PD-1 antibody (pembrolizumab) in phase 1/2 studies show promising efficacy in CCA, with about 40% response rate and the PD-L1 inhibitor (nivolumab) has just been approved for HCC, but not yet for CCA [113,114]. Here, CD274 is linked to cholangiocarcinoma.