Virgin olive oil phenols inhibit colon carcinogenesis in vitro

A mixture of phenols extracted from virgin olive oil inhibits multiple stages of colon carcinogenesis including initiation, promotion and metastasis, according to in vitro studies described in the October 20th issue of the International Journal of Cancer.

"Olive oil is suggested to be responsible in part for the beneficial nature of the 'Mediterranean diet' and our data support this view and provides some possible mechanisms for its action," Dr. Chris I. R. Gill from the University of Ulster (Coleraine) in Londonderry, North Ireland and colleagues write.Because the colon is one of the major cancer sites thought to be protected by olive oil, they studied the potential anti-cancer effects of virgin olive oil phenols in cultured cell lines widely used as models for colorectal cancer.Incubation of HT29 cells with increasing concentrations of olive oil phenols for 24 hours protected the cells from DNA damage - inducing hydrogen peroxide challenge. The observed anti-genotoxic effects have been previously observed using polyphenols from other sources including tea and red wine, the authors note.The olive oil phenols also significantly increased barrier function of CACO2 cells after 48 hours of exposure compared to untreated cells, suggesting that they may "exert an anti-promoter effect in the carcinogenesis pathway."Dr. Gill's group also observed a significant reduction in the invasiveness of HT115 colon cancer cells with the addition of olive oil phenols.In conclusion, "we have demonstrated that phenols extracted from virgin olive oil are capable of inhibiting several stages in colon carcinogenesis in vitro," the authors write."The next stage would be to assess the effects in a suitable animal model."(Source: Int J Cancer 2005;117:1-7: Reuters Health: Oncolink: November 2005.)