Abstract C59: Use of dietary antioxidant supplement during cancer therapy- pros and cons.

Abstract

Abstract Black and green teas are rich in antioxidants and its flavonoids like thearubigins, epicatechins and catechins are known to have higher antioxidant efficacy than vitamin C. Despite significant research investigating the use of tea as dietary antioxidant supplement during conventional chemotherapy, no conclusion has been drawn regarding its mechanism of action and safety. In the present study chemopreventive effects of black tea extract (BTE) were evaluated on normal lymphocytes and compared with cancerous K562 cells. Chemotherapeutic drugs (Adriamycin and Daunomycin) act by generating oxidative stress and inducing apoptosis. The level of reactive oxygen species (ROS), apoptosis and gene expression in untreated and BTE treated cells were followed by different biochemical assays, flow cytometry and reverse transcription PCR. Results evidence that efficient scavenging of intracellular ROS by BTE resulting in reduced apoptotic cell population in normal lymphocytes. Gene expression of p53, bax, bcl2 and nrf2 show variation in untreated and BTE treated cells. Activity of endogenous antioxidant enzymes like SOD, GST and catalase is modified on tea treatment. Similar observations were recorded to a lower extent in K562 cells, suggesting BTE conferred protection to cancerous cells also. It can be summarized here that tea as a dietary supplement during chemotherapy shows interference in chemotherapeutic efficacy of the drugs in vitro. More in vitro, in vivo and clinical trials would shed light on the mechanism of action of the dietary antioxidant supplement during chemotherapy and its application. Citation Information: Mol Cancer Ther 2013;12(11 Suppl):C59. Citation Format: Debjani Ghosh, Subrata Dey, Chabita Saha. Use of dietary antioxidant supplement during cancer therapy- pros and cons. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr C59.