title: Telomerase inhibition in a mouse cell line with long telomeres leads to rapid telomerase reactivation.
abstract: The indefinite growth of cancer cells requires telomere maintenance, which, in the majority of mammalian cancers is mediated via the enzyme telomerase. The core components of telomerase are a catalytic reverse transcriptase (hTERT in human, mTERT in mouse) and an RNA (TR) that contains the template for the replenishment of telomeres. Fundamental differences in human and mouse telomerase and telomere biology should be considered when using mouse models for the study of human cancers. The responses to telomerase inhibition by the expression of a catalytically-inactive dominant-negative mutant of hTERT (hTERT-DN) vary in human cells with different telomere lengths. Only one similar study has been performed in a mouse cell line with short telomeres (RenCa, 7 kb). Thus, we asked whether the responses to telomerase inhibition are also telomere-length dependent in mouse cells by analyzing long-term stable expression of mTERT-DN in the CB17 cell line (telomere length, 11 kb). A brief initial telomerase inhibition was insufficient to mediate telomere shortening and led to extremely rapid telomerase reactivation due to an increase in the level of expression of the endogenous mTERT. Thus, mouse cells, in contrast to human cells may not tolerate telomerase inhibition by introduction of mTERT-DN, independently of telomere length.
authors: Department of Anatomy & Cell Biology, McGill University, Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montréal, Québec, Canada H3T 1E2.
authors: Delphine T
authors: DT
authors: Marie-Egyptienne
authors: Marie Eve
authors: ME
authors: Brault
authors: Shusen
authors: S
authors: Zhu
authors: Chantal
authors: C
authors: Autexier
mesh_terms: D020816:Amino Acid Motifs / Q000235:genetics; D019943:Amino Acid Substitution / Q000235:genetics; D000818:Animals; D002453:Cell Cycle / Q000235:genetics; D002455:Cell Division / Q000235:genetics*; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic / Q000235:genetics* / Q000378:metabolism; D016922:Cellular Senescence / Q000235:genetics*; D002999:Clone Cells / Q000378:metabolism; D004789:Enzyme Activation / Q000235:genetics; D005786:Gene Expression Regulation / Q000235:genetics; D051379:Mice; D009154:Mutation / Q000235:genetics; D013045:Species Specificity; D019098:Telomerase / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000378:metabolism*; D016615:Telomere / Q000235:genetics*
chemical_list: D019098:Telomerase