Changes in Plasma Lipid Peroxidation and the Antioxidant System in Women with Breast Cancer

Background: Oxidative stress plays a key role in carcinogenesis. Resistance of many cells against oxidative stress is associated with high intra cellular levels of glutathione. The antioxidant enzymes GPx and catalase are involved in the removal of lipid hydroperoxides. Objectives: The aim of our study is to determine the role of oxidative stress in the induction of breast cancer and to establish the effect of antioxidants in the treatment of breast cancer. Methods: The changes in lipid peroxidation and antioxidants were studied in breast cancer patients at different clinical stages. The results were compared with age and sex matched controls. Results: Plasma lipid peroxidation was found to be increased with the progression of breast cancer from stage I to stage IV. GSH levels in the erythrocytes of breast cancer patients were decreased in all clinical stages of breast cancer, when compared to control. Catalase and Glutathione peroxidase activities were elevated significantly from stage II to stage IV of breast cancer patients, whereas no significant change was observed in stage I, when compared to control. Serum iron levels were also increased significantly from stage II to stage IV. Conclusions: Enhanced lipid peroxidation may be a cause for the induction of breast cancer. The enhanced lipid peroxidation may be due to serum iron over load in these patients. Further, the serum iron levels were correlated with the extent of lipid peroxidation observed in different stages of breast cancer.