Abstract 1997: Resveratrol modifies the activity and expression of antioxidant enzymes in somatic cancer cells

Abstract

Abstract Background & Objectives: Resveratrol has been reported as a potent anti-cancer compound, but it's mode of action is not completely understood. In this study, we investigated the effects of resveratrol treatment on the activity and expression of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPX) in three somatic cancer cell lines: PC-3 (prostate cancer), MCF-7 (breast cancer) and HepG2 (hepatocellular cancer). Methods: The cells were treated with different concentration (0-200 μM) of resveratrol for 24, 48 and 72 hours.Cell growth was studied by cell counting; cell homogenate was taken for the measurement of enzyme activities; proteins were isolated for western blotting to measure the genetic expression. Results: Resveratrol showed dose-dependent growth inhibitory activity in all cells. It was significantly effective against PC-3 and HepG2 even in 10 μM, and 25 μM concentration, but not in MCF-7 cells. However 50 μM showed significant growth inhibitory effect in MCF-7, and also in HEK293T (human embryonic kidney cell line as control) cells. 25 μM was identified as most effective dosage against PC-3 and HepG2 cells, without affecting HEK293T cells. Treatment of 25 μM for 48 hours increased the activity of SOD enzymes by 3-4 folds in PC-3; 2-3 folds in HepG2; 1.5-1.8 folds in MCF-7; and 1.2-1.5 folds in HEK293T cells. Resveratrol treatment also significantly increased the activity of CAT in HepG2, moderately in MCF-7, but non-significantly in PC-3 and HEK293T cells. However, the treatment of resveratrol showed no significant change in GPX activity in any cell line. Western blotting also revealed the increased expression of SOD2 in PC-3, and HepG2 cells at 25 μM resveratrol treatment. CAT expression was moderate, but no change in GPX1 expression was found in the tested cancer cells. Conclusions: The results of this study could confirm the dose dependent growth inhibitory potential of resveratrol; however, the dose of resveratrol in treatment of the cancer cells should be limited, as higher dose (Δ50 μM) has also been found dangerous for normal cells (HEK293T). Resveratrol at low dose (25 μM) potentially increases the activity and expression of SOD enzyme in cancer cells while inhibiting cell growth. Moderate increase of CAT activity and expression is also observed, but no significant change in GPX activity and expression in cell lines used in this study. These findings may contribute to understanding the mechanisms of resveratrol action in treatment of cancer. The work was supported by the National Basic Research Program of China (No. 2011CB910700-704) Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1997. doi:1538-7445.AM2012-1997