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Hypermethylation of replicating hepatic DNA following N-methyl-N-nitrosourea administration

✍ Scribed by Darja Kanduc; Antonella Aresta; Emmanuel Farber

Publisher: John Wiley and Sons
Year: 1994
Tongue: French
Weight: 525 KB
Volume: 58
Category: Article
ISSN: 0020-7136
DOI: 10.1002/ijc.2910580322

No coin nor oath required. For personal study only.

✦ Synopsis

Changes in the degree of methylation of cytosine in DNA are considered to be mechanistically important in modulating gene expression. To gain a better understanding of the relationship(s) linking onco-proliferative processes and enzymatic DNA methylation, a study has been carried out on the hepatic DNA methylation pattern during DNA replication following partial hepatectomy (PH), mitogen treatment and N-methyl-Nnitrosourea (MNU) administration in rats. The following results were obtained: (i) DNA hypomethylation was seen during DNA synthesis, with each of the 3 stimuli, namely MNU administration, partial hepatectomy, and hepatomitogen treatment; (ii) the level of DNA hypomethylation was not quantificatively related to the extent of DNA replication as measured by incorporation of rH]thymidine into hepatic DNA, (iii) MNU administration under conditions conducive to carcinogenic development, i.e. during the S phase of compensatory cell proliferation, caused hypermethylation of replicating hepatic DNA, as shown by Hpall and Mspl restriction patterns.

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