ω-3 PUFAs and colon cancer: experimental studies and human interventional trials

Colon cancer represents one of the most frequent forms of cancer worldwide. There is plenty of evidence to support the notion that chemoprevention is a major component of colon cancer control, and that dietary fats influence the rate of incidence of this kind of cancer. In particular, a variety of experimental studies conducted on animals subject to chemical carcinogenesis of colon, transplanted with colon cancer cells, or representing a genetic model of colon cancer, have demonstrated the ability of diets at high content of ω-3 polyunsaturated fatty acids (PUFAs) to reduce the risk, growth and progression of colon cancer. Several of these studies have also emphasized the importance of a reduced dietary ω-6 PUFA/ω-3 PUFA ratio to diminish the risk. The beneficial anti-tumor effects of ω-3 PUFAs have been also largely demonstrated in colon cancer cells treated in vitro with these fatty acids. The synergic action of combinations of ω-3 PUFAs and other anti-neoplastic agents have been also demonstrated both in vivo and in vitro. On the contrary, just a few human interventional trials have been conducted so far, but there is complete agreement among them and with the experimental studies on the anti-tumor efficacy of increased dietary intakes of ω-3 PUFAs.