Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 1/27/2012
Publication Date: 3/1/2012
Citation: Borreson, E., Forster, G., Kumar, A., Keller, A., Chen, M., Mcclung, A.M., Weir, T.L., Wdowik, M., Ryan, E. 2012. Rice bran phytochemicals and dietary colon chemoprevention teamwork. Rice Technical Working Group Meeting Proceedings. Hot Springs, AR Feb. 27 - Mar. 1, 2012. pg. 160-161. Interpretive Summary:
Technical Abstract: A growing body of evidence supports that dietary rice bran exhibits gastrointestinal cancer control and prevention activity using carcinogen induced animal models and human colon cancer cell lines. Our laboratory has recently reported metabolomic differences in rice from globally and genetically distinct varieties, and we hypothesize that bran compounds from these different rice cultivars exhibit variability for inhibition of colon cancer viability. Bioactive rice bran components, including tocotrienols and tocopherols (alpha, gamma, delta), gamma oryzanol, ferulic acid, total phenolics and fatty acid profiles were quantified from 20 diverse varieties using biochemical assays, HPLC and GC-MS. Seven varieties were selected that showed a range of total bran oil content (6-16% total lipids) and were analyzed for differences in colon cancer viability in vitro by alamar blue staining and MTS assays. Correlation analysis was performed to identify significant associations between bioactive compounds and colon cancer growth inhibition. Differences in the ratios and stoichiometry of rice bran components support potential for additive/synergistic effects of rice bran. Rice bran contains a number of colon chemopreventive agents that target multiple key hallmarks and metabolic mechanisms in cancer, and dietary intervention strategies with whole rice bran consumption are warranted for enhanced efficacy. Pilot data from a prospective, placebo controlled, dietary rice bran intervention study titled ‘BENEFIT’ (Bran-rice Enriching Nutritional Eating For Intestinal health Trial) demonstrates translational feasibility of increasing rice bran intake in healthy adults and colon cancer survivors. The accessibility, affordability, and availability of dietary rice bran further support the strong public health impact potential for novel “phytochemical teamwork” based colon cancer control and chemoprevention strategies. This work was supported by NCI-Cancer Prevention Grant program, 5R03CA150070-2.