1070 Dietary prevention of colon cancer: phytochemical protection of DNA damage and induction of DNA repair in colonocytes

Abstract

Effects of freeze-dried potato powder, prepared from baked potato with skin and incorporated into a purified diet, on the post-initiation phase of chemically induced breast carcinogenesis in rats, were evaluated for both dose dependence and variation in anticancer activity among cultivars. Associations among anticancer activity, select phytochemicals, and antioxidant capacity were investigated. No adverse effects were observed in rats fed diets containing between 5% and 50% (w/w) freeze-dried potato powder. While Russet Burbank potato (RB) (5%, w/w) had marginal effects on the carcinogenic response, feeding a range of dietary concentrations (12.5%, 25%, and 50%, w/w), of a red pigmented cultivar, cv. Mountain Rose (MR), with higher content of chlorogenic acid derivatives and anthocyanin content than RB, showed greater inhibition of carcinogenesis. Overall, MR-fed rats had a 23% reduction in cancer incidence (p = 0.009) and a 49% reduction in cancer multiplicity (2.1 vs. 4.0 cancers per rat, p = 0.004) with evidence of a dose dependent effect on cancer multiplicity. Evaluation of additional cultivars showed significant variation for anticancer activity that is likely to be sufficient to build upon for crop breeding and improvement.