Similar to G6PD overexpressed HCC cells, cell apoptosis rates of regorafenib-resistant cells were decreased under conditions of H2O2, CoCl2 and hypoxia when compared with HCC cells (Fig. 4C, D), demonstrating that anti-oxidative stress ability was increased in regorafenib-resistant cells, which may depend on increased G6PD expression. This evidence concerns the gene G6PD and hepatocellular carcinoma.