This is the case of circKDM4C that sponges miR let-7b-5p to upregulate p53, thereby promoting p53-dependent ferroptosis pathways [91] and circRNA IL4R that inhibits miR-541-3p to enhance GPX4 expression, thus impairing ferroptosis in hepatocellular carcinoma [92]. This evidence concerns the gene GPX4 and hepatocellular carcinoma.