FTH1 and intrahepatic cholangiocarcinoma: For example, circPIAS1 (circBase ID: hsa_circ_0007088) promotes hepatocellular carcinoma progression by inhibiting ferroptosis via the miR-455-3p/NUPR1/FTH1 axis [14], whereas circFOXP1 encodes a protein isoform (circFOXP1-231aa) that activates ferroptosis pathways to prevent recurrence in intrahepatic cholangiocarcinoma (ICC) [15].