FTO and hepatocellular carcinoma: Elevated FTO expression in hepatocellular carcinoma cells removes m6A modification on circRNA GDI2, circRNA GDI2 expression is elevated and binds to IGF2BP2 to promote IGF2BP2 expression, and highly expressed IGF2BP2 promotes the expression of PKM2 thereby enhancing the level of glycolysis in the cancer cells, and promoting the malignant process of hepatocellular carcinoma.