BORIS/CTCFL-mediated transcriptional regulation of the hTERT telomerase gene in testicular and ovarian tumor cells.

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Serval ID
serval:BIB_53B2E2E10050
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
BORIS/CTCFL-mediated transcriptional regulation of the hTERT telomerase gene in testicular and ovarian tumor cells.
Journal
Nucleic Acids Research
Author(s)
Renaud S., Loukinov D., Alberti L., Vostrov A., Kwon Y.W., Bosman F.T., Lobanenkov V., Benhattar J.
ISSN
1362-4962 (Electronic)
ISSN-L
0305-1048
Publication state
Published
Issued date
2011
Volume
39
Number
3
Pages
862-873
Language
english
Abstract
Telomerase activity, not detectable in somatic cells but frequently activated during carcinogenesis, confers immortality to tumors. Mechanisms governing expression of the catalytic subunit hTERT, the limiting factor for telomerase activity, still remain unclear. We previously proposed a model in which the binding of the transcription factor CTCF to the two first exons of hTERT results in transcriptional inhibition in normal cells. This inhibition is abrogated, however, by methylation of CTCF binding sites in 85% of tumors. Here, we showed that hTERT was unmethylated in testicular and ovarian tumors and in derivative cell lines. We demonstrated that CTCF and its paralogue, BORIS/CTCFL, were both present in the nucleus of the same cancer cells and bound to the first exon of hTERT in vivo. Moreover, exogenous BORIS expression in normal BORIS-negative cells was sufficient to activate hTERT transcription with an increasing number of cell passages. Thus, expression of BORIS was sufficient to allow hTERT transcription in normal cells and to counteract the inhibitory effect of CTCF in testicular and ovarian tumor cells. These results define an important contribution of BORIS to immortalization during tumorigenesis.
Pubmed
Web of science
Open Access
Yes
Create date
22/03/2011 11:53
Last modification date
20/08/2019 14:08
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