Furthermore, non-protein thiol such as GSH in conjugation with glutathione-S-transferase (GST) and glutathione peroxidase (GPx), plays a important role in defensive mechanism of cells against ROS.17 In our study a major reduction of plasma GSH observed reflects enhanced pro-oxidant level of the cells and interact with the increased lipid peroxides in the patients with oral cancer. The gene discussed is HPGDS; the disease is lip and oral cavity carcinoma.