Cancer chemoprevention by phytochemicals. Expectation for phytochemicals as preventive agents against radiation-induced carcinogenesis

There is growing evidence from the studies using animal models that phytochemicals in plants have preventive effect on cancer induction, which is mediated by polyphenol anti-oxidative and anti-inflammatory functions. Some phytochemicals such as curcumin and epigallocatechin gallate have been moved onto clinical trials. These phytochemicals are also expected to reduce the deleterious effect of radiation, and to be a powerful tool for the prevention of radiation carcinogenesis. In this review, we summarized the general concept of cancer chemoprevention and usefulness of phytochemicals as cancer preventive agents, and pointed out their possibilities for prevention of radiation-induced carcinogenesis. (author)