FIS1 and hepatocellular carcinoma: Given that circFOXK2 could directly bind to miR-484 and miR-484 could inhibit the Warburg effect via regulating Fis1 expression, we carried out rescue experiments to detect whether circFOXK2 promotes the Warburg effect of HCC cells via not only encoding FOX2-142aa to regulate LDHA phosphorylation, but also acting as a ceRNA to sponge miR-484 followed by affecting Fis1-related mitochondrial fission.