Review article: the chemoprevention of colorectal carcinoma.

This review aims to provide an insight into some of the common pathways involved in the development of colorectal cancer--so-called chromosomal instability and microsatellite instability. There is both clinical and molecular evidence to show that colorectal cancer development occurs over an extended period of time. Together with a knowledge of the molecular pathogenesis of colorectal cancer, this time window allows physicians to counteract cancer development, a strategy known as chemoprevention. In familial and sporadic colorectal cancer, aspirin, other nonsteroidal anti-inflammatory drugs and cyclo-oxygenase-2 inhibitors have been tested for their ability to reduce polyp and cancer development in clinical studies. In inflammatory bowel disease-related colorectal cancer, evidence from retrospective case-control studies shows that mesalazine (mesalamine) can reduce the development of dysplastic lesions or cancer. Although the mechanisms behind this are incompletely understood, general anti-inflammatory, oxygen scavenger and some pro-apoptotic and cyclo-oxygenase inhibitory activities of mesalazine are thought to be involved. New molecular evidence points to a direct DNA stabilizing effect of mesalazine, resulting in a significant reduction of spontaneous microsatellite mutations.