Carcinogenesis, Vol 19, 1777-1781, Copyright © 1998 by Oxford University Press
NG Lopatina, BF Vanyushin, GM Cronin and LA Poirier
DNA methyltransferase (MTase) activity in nuclear extracts from neoplastic
and preneoplastic livers of rats fed a methyl-deficient diet (MDD) is
elevated compared with that seen in the livers of control rats. Nuclear
proteins were prepared in the presence of protease inhibitors including
trans-epoxy succinyl-L-leucylamido-(4- guanido)butane and were fractionated
by isoelectric focusing. In normal, control liver, two distinct MTase
fractions were observed. In MDD-induced malignant liver, a third fraction,
in addition to the previous two, was also seen. Both the DNA substrate and
the cytosine site specificities of the third MTase fraction differ from
those of the other two fractions. The distinct MTase activity in liver
tumor has significantly more de novo MTase activity than do the MTase
fractions of normal, control liver. Thus, normal and neoplastic rat livers
differ in DNA MTase fractionation patterns and site specificities. The
altered DNA MTase activity observed in rat liver tumors caused by MDDs may
be one of the critical factors contributing to cancer formation through
abnormal DNA methylation.
ARTICLES
Elevated expression and altered pattern of activity of DNA methyltransferase in liver tumors of rats fed methyl-deficient diets
Division of Nutritional Toxicology, National Center for Toxicological Research, Jefferson, AR 72079, USA.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
K. T. Williams, T. A. Garrow, and K. L. Schalinske Type I Diabetes Leads to Tissue-Specific DNA Hypomethylation in Male Rats J. Nutr., November 1, 2008; 138(11): 2064 - 2069. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Zhang, S. E. Hankinson, D. J. Hunter, E. L. Giovannucci, G. A. Colditz, and W. C. Willett Folate Intake and Risk of Breast Cancer Characterized by Hormone Receptor Status Cancer Epidemiol. Biomarkers Prev., August 1, 2005; 14(8): 2004 - 2008. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. D. Niculescu and S. H. Zeisel Diet, Methyl Donors and DNA Methylation: Interactions between Dietary Folate, Methionine and Choline J. Nutr., August 1, 2002; 132(8): 2333S - 2335. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. A. Poirier The Effects of Diet, Genetics and Chemicals on Toxicity and Aberrant DNA Methylation: an Introduction J. Nutr., August 1, 2002; 132(8): 2336S - 2339. [Abstract] [Full Text] [PDF] |
||||
![]() |
C.-H. Lin, S.-Y. Hsieh, I-S. Sheen, W.-C. Lee, T.-C. Chen, W.-C. Shyu, and Y.-F. Liaw Genome-wide Hypomethylation in Hepatocellular Carcinogenesis Cancer Res., May 1, 2001; 61(10): 4238 - 4243. [Abstract] [Full Text] |
||||
![]() |
L. Tao, S. Yang, M. Xie, P. M. Kramer, and M. A. Pereira Effect of Trichloroethylene and Its Metabolites, Dichloroacetic Acid and Trichloroacetic Acid, on the Methylation and Expression of c-Jun and c-Myc Protooncogenes in Mouse Liver: Prevention by Methionine Toxicol. Sci., April 1, 2000; 54(2): 399 - 407. [Abstract] [Full Text] [PDF] |
||||



