Objectives: To evaluate the extent of lipid peroxidation and the antioxidant levels in breast cancer patients in relation to different clinical stages and menopausal status.
Design and methods: Fifty newly diagnosed women with adenocarcinoma of the breast were divided into different groups based on clinical staging and menopausal status. The extent of lipid peroxidation as reflected by the formation of thiobarbituric acid-reactive substances (TBARS), lipid hydroperoxides (LOOH), and conjugated dienes (CD) as well as the status of the antioxidants superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and glutathione peroxidase (GPx) in tumor tissues and adjacent normal tissues were estimated in these patients.
Results: Enhanced lipid peroxidation accompanied by significant elevation in enzymatic and nonenzymatic antioxidants was observed in breast tumor tissues compared to the corresponding uninvolved adjacent tissues irrespective of clinical stage and menopausal status of the patients. The magnitude of change in tissue oxidant-antioxidant status was, however, more pronounced in stage III and in premenopausal patients compared to stage I and II and postmenopausal patients, respectively.
Conclusion: A correlation between tissue redox status and tumor progression suggests that upregulation of antioxidants enables tumor cells to counter oxidative stress, thereby conferring a selective advantage for growth compared to corresponding normal cells.