The level of glutathione was confirmed to be associated with the proliferation of human HCC cell line in vitro and the increased level of glutathione was found in human HCCs, as a result of upregulated expression of γ-glutamylcysteine synthetase heavy subunit (GCS-HS) and glutathione synthetase (GS) [25]. This evidence concerns the gene GLUL and hepatocellular carcinoma.