Non-steroidal anti-inflammatory drugs and selective apoptotic anti-neoplastic drugs in the prevention of colorectal cancer: The role of super aspirins

There is increasing evidence to suggest that aspirin and other non-steroida l anti-inflammatory drugs reduce the risk of colorectal cancer. This observ ation is supported by animal studies that show fewer tumors per animal and fewer animals with tumors after administration of several different NSAIDs. Intervention data in familial adenomatous polyposis have established that the effect is exerted on the process of human colonic adenoma formation. Su pportive evidence in sporadic colorectal neoplasia, derived from 22 of 24 s tudies (both case-control and cohort), found a reduced risk in men and wome n for cancers of the colon and the rectum and for both aspirin and the othe r NSAIDs. Earlier detection of lesions as a result of drug-induced bleeding does not seem to account for these findings. Although the molecular mechan ism responsible for the chemopreventive action of this class of drugs is no t yet completely understood, the protection may affect several pathways inc luding both cell cycle arrest and induction of apoptosis. In the third millennium the question is not ii but how. Based on the consis tency of epidemiological, clinical and experimental data, the association b etween regular longterm aspirin or NSAIDs intake and a decreased death rate from colorectal cancer is sound and there is no need for further placebo t rials. At the same time, despite this consistency there is no clear data on the dose, duration or frequency of use for cancer-preventive activity.