Abstract 573: 18alpha- glycyrrhetinic acid (AGA) inhibits advanced prostate cancer cell proliferation and induces apoptosis by downregulating inflammation-related cytokine growth factor genes

Glycyrrhetinic acid is an active triterpenoid metabolite of glycyrrhizin abundantly present in licorice roots. Glycyrrhetinic acid exists as alpha and beta stereo-isomeric forms. Both stereo-isomeric forms are known to have anti-inflammatory and anti-cancer activity. However, the effects and anti-cancer mechanism of alpha glycyrrhetinic acid in prostate cancer cells is not yet evaluated. Therefore in this study, we have investigated the growth inhibition, induction of apoptosis and the anti-cancer mechanisms of 18α-glycyrrhetinic acid (AGA) on androgen independent metastatic prostate cell line DU-145. Our results showed that AGA inhibited proliferation and growth of these cells in a time and dose dependent manner. Induction of apoptosis was confirmed by Annexin V-FITC and propidium iodide staining. Further analysis showed that AGA treatment activated caspase- 8 and −3 death related enzymes in DU-145 cells. Interestingly, AGA treatment also simultaneously down regulated the expression of proinflammatory cytokine/growth factor genes HMGB1, IL-6 and IL-8. This is the first report demonstrating that AGA could play a dual role as an inducer of apoptosis and suppressor of pro-inflammatory gene expression in DU-145 prostate cancer cells. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 573.