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Telomerase inhibition alters telomere maintenance mechanisms in laryngeal squamous carcinoma cells

Published online by Cambridge University Press:  20 April 2010

W Chen
Affiliation:
Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, China
S M Chen
Affiliation:
Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, China
Y Yu
Affiliation:
Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, China
B K Xiao
Affiliation:
Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, China
Z W Huang
Affiliation:
Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, China
Z Z Tao*
Affiliation:
Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, China
*
Address for correspondence: Dr Zezhang Tao, Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, Wuhan 430060, China. Fax: (86)027 88042292 E-mail: [email protected]

Abstract

Background and purpose:

Telomere length must be maintained throughout cancer cell progression and proliferation. In most tumours, telomerase activity maintains telomere length. Therefore, telomerase is a target for cancer treatments. However, some cancer cells maintain telomere length through an alternative mechanism termed ‘alternative lengthening of telomeres’. To determine how telomerase inhibition relates to the initiation of the alternative lengthening of telomeres pathway, we investigated telomerase activity and telomere maintenance in Hep-2 cells with and without reduced telomerase activity.

Materials and methods:

We investigated telomerase activity levels in a normal Hep-2 cell line and in residual cells following telomerase inhibition treatment. Additionally, we looked for expression of a marker protein for the alternative lengthening of telomeres mechanism.

Results and conclusions:

In the residual cells, telomerase activity was eliminated. However, these cells had higher levels of the alternative lengthening of telomeres biomarker, suggesting an alternative mechanism for telomere maintenance following telomerase inhibition. These results could have a major impact on the design of new cancer treatments.

Type
Main Articles
Copyright
Copyright © JLO (1984) Limited 2010

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