Hypomethylation-Associated Expression of Cytochrome P-450 and γ-Glutamyl Transpeptidase During Hereditary Hepatocarcinogenesis in LEC Rats
Recent evidence suggests that the methylation of specific cytosine residues in DNA is an important factor in regulating gene expression and differentiation in eukaryotes [1, 2]. Alterations in the levels and patterns of 5-methyldeoxycytidine have been implicated in many of the basic gene processes of mammalian cells involved in embryogenesis, carcinogenesis, and cell differentiation [3, 4]. Hypomethylation of regulatory regions of genes is often associated with enhanced transcriptional activity during carcinogenesis [5, 6]. The compiled evidence for this view is based mainly upon the development of tumors elicited by choline-deflcient diets which decrease the availability of substrates for DNA methylations in animal models.
KeywordsEukaryotic Gene Expression Chemical Hepatocarcinogenesis Metabolic Predisposition Cytosine Demethylation Spontaneous Hepatitis
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