Plasma Selenium Concentration and Glutathione Peroxidase Activity in Breast Cancer Patients Before and After Chemotherapy

Abstract Background : The chemotherapeutic agents used for treatment of breast cancer are all shown to increase free oxygen radicals and generation of reactive oxygen species. The aim of this study was to evaluate effect of chemotherapy on plasma selenium (Se) concentration and glutathione peroxidase (GPX) activity in breast cancer patients. Materials and Methods : Seventeen women in stage II and III breast cancer were randomly selected from their population. Plasma Se was measured with Graphite furnace atomic absorption spectroscopy and GPX activity in erythrocyte by using spectrophotometric at baseline (before chemotherapy) and after chemotherapy. normally distributed data was expressed as mean ± standard deviation. Statistical analysis was performed using Paired T-Test. Results : plasma Se concentration before and after chemotherapy was in normal range and no statistically difference was observed (156.23±25 μg/L vs. 145.23±23 μg/L respectively). After chemotherapy, there was a significant (p<0.05) higher erythrocyte GPX activity, as compared to initial activity at baseline. (22.28±4 U/grHb vs. 26.39± 4 U/grHb respectively). Conclusion : This study indicates that sufficient Se could increase GPX activity with have a protective effect against oxidative damages. Keywords : breast cancer, chemotherapy, glutathione peroxidase, selenium References 1. Weijl NI, Cleton FJ, Osanto S. Free radicals and antioxidants in chemotherapy-induced toxicity. Cancer Treat Rev. 1997; 23(4):209-240. 2. Sangeetha P, Das UN, Koratkar R, Suryaprabha P. Increase in free radical generation and lipid peroxidation following chemotherapy in patient with cancer. Free Radic Biol Med. 1990; 8(1):15-19. 3. Clemens MR, Ladner C, Schmidt H, Ehninger G, Einsele H, Buhler E, et al. Decreasal essential antioxidant and increased lipid hydroperoxides following high-dose radiochemotherapy. Free Radic Res Commun. 1989; 7(3- 6):227-232. 4. Ambrosone CB, Ahn J, Schoenenberger V. Antioxidant Supplements, Genetics and Chemotherapy Outcomes. Current Cancer Therapy Reviews. 2005; 1:251-258. 5. Abidi S, Ali A. Role of oxygen free radicals in the pathogenesis and etiology of cancer. Cancer Lett. 1999; 142:1-9. 6. Patricle l. Selenium Biochemistry and Cancer: A Review of The Literature. Alternative Medicine Review. 2004; 9:239-58. 7. Howard E.Ganther. Selenium metabolism, selenoproteins and mechanisms of cancer prevention: complexities with thioredoxin reductase. Carcinogenesis. 1999; 20(9):657- 1666. 8. Rayman Margaret P. The Importance of Selenium to Human Health. The lancet. 2000; 356:233-41. 9. Clement IP. Lessons From Basic Research In Selenium And Cancer Prevention. J Nutr. 1998;128:845-1854. 10. Sobin LH, Wittenkind CH, editors. International Union against Cancer (UICC): TNM classification of malignant tumors. 5nd edition. New York. Wiley Liss Publications.1997. 11. Sheehan TM, Halls DJ. Measurment of selenium in clinical specimens. Ann Clin Biochem. 1999; 36:301-315. 12. Paglia DE, Valentine WN. Studies on the quantitative and qualitative characterization of erythrocyte glutathione peroxidase. J Lab Clin. 1967; 70:158-169. 13. Schumacher K. Effect of selenium on the side effect profile of adjuvant chemotherapy/radiotherapy in patients with breast cancer carcinoma. Design for clinical study. Med Klin. 1990; 94(3):45-8. 14. Breedlove HA, Smith AM, Burk RF, Hill KE, Shapiro CL. Serum selenium measurements in women with early-stage breast cancer with and without chemotherapy-induced ovarian failure. Breast Cancer Research and treatment. 2006; 97(3):225-230. 15. Faber m, Coudray C, Hida H, Mousseau M, Favier A. Lipid peroxidation products, and vitamin and trace element status in patients with cancer before and after chemotherapy, including adriamycin. A preliminary study. Biol Trace Elem Res. 1995; 47(1-3):117-23. 16. Jonas CR, Puckett AB, Jones DP, Griffith DP, Szeszycki EE, Bergman GF, et al. Plasma antioxidant status after high-dose chemotherapy: a randomized trial of parenteral nutrition in bone marrow transplantation patients. Am J Clin Nutr. 2000; 72:181-9.