Publication Date:
1991-02-15
Description:
Transfer of a normal Chinese hamster X chromosome (carried in a mouse A9 donor cell line) to a nickel-transformed Chinese hamster cell line with an Xq chromosome deletion resulted in senescense of these previously immortal cells. At early passages of the A9/CX donor cells, the hamster X chromosome was highly active, inducing senescence in 100% of the colonies obtained after its transfer into the nickel-transformed cells. However, senescence was reduced to 50% when Chinese hamster X chromosomes were transferred from later passage A9 cells. Full senescing activity of the intact hamster X chromosome was restored by treatment of the donor mouse cells with 5-azacytidine, which induced demethylation of DNA. These results suggest that a senescence gene or genes, which may be located on the Chinese hamster X chromosome, can be regulated by DNA methylation, and that escape from senescence and possibly loss of tumor suppressor gene activity can occur by epigenetic mechanisms.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Klein, C B -- Conway, K -- Wang, X W -- Bhamra, R K -- Lin, X H -- Cohen, M D -- Annab, L -- Barrett, J C -- Costa, M -- ES 04715/ES/NIEHS NIH HHS/ -- ES 04895/ES/NIEHS NIH HHS/ -- ES 05512/ES/NIEHS NIH HHS/ -- New York, N.Y. -- Science. 1991 Feb 15;251(4995):796-9.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute of Environmental Medicine, New York University Medical Center, NY 10016.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/1990442" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Cell Fusion
;
Cell Line, Transformed
;
Cell Survival/*genetics
;
Cell Transformation, Neoplastic/chemically induced/*genetics
;
Chromosome Deletion
;
Cricetinae
;
Cricetulus
;
Hypoxanthine Phosphoribosyltransferase/genetics
;
Mice
;
Nickel/*pharmacology
;
X Chromosome/*drug effects
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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