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 


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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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