Gastrointestinal tract carcinogenesis

O Neill IK, Bingham S, Povey AC, et al. 1990a. Modulating effects in human diets of dietary fibre and beef, and of time and dose on the reactive microcapsule trapping of benzo[a]pyrene metabolities in the rat gastrointestinal tract. Carcinogenesis 11(4) 599-607. 

The metabolic activity of various tissues is also a determinant of susceptibility to tumor production. The gastrointestinal tract is resistant to dime thy Ini trosamine carcinogenesis, even when the compound is given orally, as the metabolic activity of this organ is low as far as activation of dimethylnitrosamine is concerned. 

While the mechanism involved in vitamin A action in relation to carcinogenesis remains to be elucidated, several possibilities have been suggested. For example, vitamin A deficiency may act primarily on metabolic activation of carcinogens such deficiency may facilitate interaction of ultimate carcinogen with DNA. Finally, vitamin A is required in the differentiation of epithelial cells important in both respiratory and gastrointestinal tracts, and its deficiency may affect transformation of epithelia and thus predispose the tissue to neoplastic changes. 

O Neill IK, Povey AC, Bingham S, et al. 1990b. Systematic modulation by human diet levels of dietary fibre and beef on metabolsim and disposition of benzo[a]pyrene in the gastrointestinal tract of Fischer F344 rats. Carcinogenesis 11(4) 609-616. 

Chandra, S.A., Nolan, M.W., and Malarkey, D.E. (2010) Chemical carcinogenesis of the gastrointestinal tract in rodents an overview with emphasis on NTP earcinogenesis bioassays. Toxicol. Pathol. 38, 188-197. 

Sunter, J. P., 1980, Experimental carcinogenesis and cancer in the rodent gut, in Cell Proliferation in the Gastrointestinal Tract (D. R. Appleton, J. P. Sunter, and A. J. Watson, eds.), pp. 255-277, Pitman Medical Ltd., Tunbridge Wells, Kent. 

Andorfer, J.H., Tchaikovskaya, T. and Listowsky, I. (2004) Selective expression of glutathione S-transferase in the murine gastrointestinal tract in response to dietary organosulphur compounds. Carcinogenesis, 25,359-367. 

In addition, there is now epidemiological evidence that dietary antioxidants, such as vitamins A, C, D and E, phytic acid, and protease inhibitors can prevent carcinogenesis, including that of the gastrointestinal (GI) tract (Graf and Eaton, 1990 Block, 1991 Malone, 1991 Troll, 1991 Weisburger, 1991). 

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