Chemoprevention has received considerable attention over the last decade. The notion of using bioactive food components to reduce the risk of developing, or the recurrence of cancer has long been recognized. Resveratrol (a naturally occurring polyphenolic compound) has been studied extensively with considerable evidence demonstrating its efficacy as an anti-inflammatory and anti-cancer agent, with the most evidence for its role in colon cancer prevention. However, Resveratrol intervention studies in clinical trials still remains controversial, due to the lack of biomarkers of efficacy. Utilizing Metabolomic analysis we have identified biomarkers of efficacy in a pre-clinical model of inflammation-induced colorectal carcinogenesis.
Metabolomics is the process of identifying metabolites present in biological specimens. Our study has demonstrated the chemopreventative activity of Resveratrol in mice treated with the chemical carcinogen azoxymethane (AOM) and then exposed to colonic irritant dextran sodium sulfate (DSS) to induce inflammation-associated colon carcinogenesis. We found a diet enriched in Resveratrol resulted in a reduction in tumor incidence in AOM/DSS treated mice by 29 percent. Furthermore, we identified several biomarkers that are indicative of Resveratrol chemopreventive activities. Prior studies have shown Resveratrol's role in inhibiting several key enzymes important during the carcinogenesis process. We have correlated such findings with Metabolomic biomarkers. We found a significant reduction in Arachidonic acid, the limiting reagent of pro-inflammatory enzyme COX-2, and a reduction in spermidine a product of Ornithine decarboxylase, an enzyme that promotes proliferation. More intriguingly, we found biomarkers representing changes in bile acids by Resveratrol, which highlight chemopreventative activities that were not previously described. We found that Resveratrol treatment causes a reduction in tumorigenic secondary bile acids, deoxycholic acid and lithocholic acid, which are metabolic byproducts of intestinal bacteria. These data suggested that dietary supplementation with Resveratrol results in a healthy microbiome.
These pre-clinical studies should easily be translated into clinical studies designed to ascertain chemopreventive efficacy for bioactive compounds like Resveratrol, all with the objective to identify patients that will benefit from an intervention.
Citation Format: Shakir Saud, Matthew Young, Ed Karoly, Chris Bernard, Nancy Colburn, Young Kim. Resveratrol's Metabolomic biomarkers of efficacy: the missing link to chemoprevention. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 198. doi:10.1158/1538-7445.AM2013-198