Aamir Ghafoor Khan, Michael Lucas.
Enhanced intestinal absorption of Carcinogens of dietary origin in patients with Gastrointestinal disease and in patients receiving Calcium Channel Blockers.
J Postgrad Med Inst Jan ;16(2):121-4.

The discussion paper argument is here summarized in compressed form. There is an increased incidence of cancer in patients with gastrointestinal disease and in those patients taking calcium channel blocker. Increased carcinogen uptake is proposed to be the common factor. Dietary carcinogens exist as heterocyclic amines or can be converted into such forms by intestinal bacteria. There is increased uptake of aminoquuinolines during intestinal secretion in experimental animals, also increases weak base absorption in gut disease and reduced base secretion after verapamil exposure in animal. Hence there is likely to be increased absorption of carcinogens in the form of highly potent amnioquinolines both because of changes in intestinal mucosal surface pH and because of mdr protein inhibition. In patients on calcium channel blockers, inhibition of mdr protein is likely to inhibit efflux of dietary carcinogenic amines back into the lumen in the same way that verapamil inhibits resistance to amnioquinoline uptake in the malaria parasite. This hypothesis may additionally explain the link of incidence of cancer with dietary fat and also with the site and type of carcinoma in these diseases. This is a review article.

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