Dietary fiber and the chemopreventive modelation of colon carcinogenesis

摘要: Comparative international epidemiological data indicate that the difference between highest and lowest colon cancer incidence is approximately 10-fold. This suggests dominant causes of are environmental rather than genetic in origin, with cause being typical diet Western industrialized countries. Many experimental studies have suggested an important role for dietary fiber prevention cancer. Using Fischer-344 rat as model, clearly demonstrate a strong protective effect low fat, high calcium (low-risk diet). Such prevents development both preneoplastic aberrant crypt foci (ACF) tumors. Recent experiments also demonstrated direct relationship ras point mutation ACF at different stages carcinogenesis, subsequently present wheat bran model source, its effects were compared to psyllium, phytic acid, vitamin E, beta-carotene, folic alone or combination, their ability prevent rats on high-risk Western-style diets. Our reduce tumors consumed high-fat, Although which constituent bran, cancer-preventive potential, our provided evidence crude fraction independent acid. The synergistic combination soluble psyllium led enhanced protection; while beta-carotene showed only additive effect. Beta-carotene appeared show higher protection intake level nutritionally relevant humans, suggesting possibility using enhance populations. intermediate endpoint, it was shown E appear inhibit progression cancer, acid weak potential this late stage carcinogenesis. In conclusion, alone, appears greater earlier phases may later Despite considerable increasing lowering fat content could substantially risk heart disease, real challenge find effective ways educate motivate people overcome intrinsic cultural resistance such changes eating habits.