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Dietary Effects on DNA Methylation: Do They Account for the Hepatocarcinogenic Properties of Lipotrope Deficient Diets?

  • Judith K. Christman
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 369)

Abstract

The first evidence suggesting that dietary deprivation of sources of one-carbon units could influence development of tumors is now almost fifty years old. In 1946, Copeland and Salmon reported that long-term feeding of a choline deficient diet increased the incidence of tumors in the liver and other organs of the rat. Once it was demonstrated that the peanut meal used in the diet was contaminated with aflatoxin (Newberne, 1965), it was assumed that the diet had in some way increased the sensitivity of cells to low levels of carcinogens. This supposition was supported by the demonstration that a variety of different diets deficient in choline and/or other lipotropes (methionine, folate and vitamin 12) increased the tumorigenicity of a wide range of carcinogens in liver and other organs (Rogers, 1975, 1993; Rogers and Newberne, 1980; Rogers et al., 1974; Shinozuka et al., 1978a, b; Lombardi and Shinozuka, 1979). Unequivocal demonstration that deficiency of lipotropes alone was sufficient to cause liver tumors was obtained by feeding of an amino-acid defined (AAD) diet lacking methionine and choline but supplemented with folate, vitamin B12 and homocystine (Mikol et al., 1983). In the absence of added carcinogens, this diet produced a high incidence of hepatomas in rats, yet was reported to “afford a slight protection against spontaneous tumor formation in extra-hepatic tissues.” These studies raised a number of questions that are yet to be resolved. Why is deficiency of lipotropes carcinogenic? Why is the liver the primary target tissue? Does moderate lipotrope deficiency play a significant role in development of human cancers?

Keywords

Pernicious Anemia Folate Deficiency Megaloblastic Anemia Peanut Meal CCGG Site 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • Judith K. Christman
    • 1
  1. 1.Molecular Oncology ProgramMichigan Cancer FoundationDetroitUSA

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