Abstract A45: Resveratrol inhibits prostate cancer stem cell characteristics by suppressing Wnt, sonic hedgehog, and Notch pathways

The existence of cancer stem cells (CSCs) in prostate cancer has profound implications for cancer prevention and/or treatment. The CSC population resides within the prostate tumor mass and they may be responsible for drug resistance, and for the recurrence of prostate cancer. Therefore, development of novel strategies to target CSCs by nontoxic agent resveratrol is an innovative and novel idea for the management of prostate cancer. Activation of Wnt, sonic hedgehog (Shh) and Notch pathways are required for the growth of numerous tissues and organs and recent evidence indicates that these pathways are often recruited to regulate self-renewal and metastasis of CSCs. The objectives of this study were to examine the molecular mechanisms by which resveratrol, an active compound in grapes and red vine inhibits self-renewal capacity of prostate CSCs. Our data demonstrated that resveratrol inhibited the expression of pluripotency maintaining transcription factors (Nanog, c-Myc and Oct-4), and spheroid formation by prostate CSCs. Inhibition of Nanog by shRNA enhanced the inhibitory effects of resveratrol on self-renewal capacity of CSCs. Resveratrol suppressed cell proliferation and induced apoptosis by inhibiting the expression of Bcl-2 and IAPs, and activating caspase-3. Interestingly, resveratrol also inhibited the transcriptional activities TCF/LEF, Gli and RBP-Jk. Furthermore, resveratrol inhibited epithelial-mesenchymal transition (EMT) by suppressing the expression of Snail, Slug and ZEB1 transcription factors, which correlated with significantly reduced CSC's migration and invasion, suggesting the blockade of signaling involved in early metastasis. In conclusion, resveratrol can inhibit prostate cancer CSC characteristics by suppressing various signal transduction pathways, and can be used for the management of prostate cancer. Citation Format: Rakesh K. Srivastava, Mariana Rodova, Junsheng Fu, Dara Nall, Sharmila Shankar. Resveratrol inhibits prostate cancer stem cell characteristics by suppressing Wnt, sonic hedgehog, and Notch pathways [abstract]. In: Proceedings of the AACR Special Conference on Advances in Prostate Cancer Research; 2012 Feb 6-9; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2012;72(4 Suppl):Abstract nr A45.