Molecular mechanisms for the anticancer activity of the carotenoid lycopene

There is extensive and consistent evidence that high intake of fruit and ve getables is associated with decreased risk of many types of cancers. Thus, it is widely accepted that diet changes are a powerful tool for cancer prev ention and for inhibition of cancer progression. The growing interest in th e role of the tomato carotenoid, lycopene, in cancer prevention and treatme nt, combined with the hypothesis that a single micronutrient cannot replace the power of a diet rich in fruit and vegetables, are the basis for this r eview. The mechanism of lycopene function in cancer cells involves interfer ence in the mitogenic pathway of IGF-I and slowdown of cell cycle progressi on. The recent observation that high plasma IGF-I levels is an important ri sk factor for breast and prostate cancer, similar to the role of cholestero l in cardiovascular diseases, further places dietary intervention in the fo cus of anticancer research. Moreover, as suggested by our studies and those of others, it is possible that derivatives of lycopene and other carotenoi ds, not only the native molecules themselves, are the active compounds, sin ce it was found that such derivatives can interact with members of the nucl ear receptor family. If an active lycopene derivative will be identified by this approach, it can be used as a parent compound for the development of a new series of potent anticancer drugs based on natural dietary ingredient s. (C) 2000 Wiley-Liss, Inc.