The LEC Rat pp 162-168 | Cite as

Hypomethylation-Associated Expression of Cytochrome P-450 and γ-Glutamyl Transpeptidase During Hereditary Hepatocarcinogenesis in LEC Rats

  • Suresh K. Jain
  • Kenji Suzuki
  • Sadhana Jain
  • Toshihiro Sugiyama
  • Naoyuki Taniguchi


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.


Eukaryotic Gene Expression Chemical Hepatocarcinogenesis Metabolic Predisposition Cytosine Demethylation Spontaneous Hepatitis 
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-Verlag Tokyo 1991

Authors and Affiliations

  • Suresh K. Jain
    • 2
  • Kenji Suzuki
    • 3
  • Sadhana Jain
    • 2
  • Toshihiro Sugiyama
    • 1
  • Naoyuki Taniguchi
    • 1
  1. 1.Department of BiochemistryOsaka University Medical SchoolOsaka, 565Japan
  2. 2.Department of Molecular PharmacologyAlbert Einstein College of MedicineBronxUSA
  3. 3.International Research LaboratoriesCIBA-GEIGY JapanTakarazuka, 665Japan

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