Increased expression of telomere-related proteins correlates with resistance to radiation in human laryngeal cancer cell lines

Abstract

Telomere-associated proteins function as survival factors in telomere maintenance, which are major contributors to radiosensitivity in human cancers. The aim of this study was to investigate the association of telomere-associated gene expression and radiation resistance in human larynx squamous carcinoma. The changes of telomere-associated gene expressions and bionomical characteristics that occur in two human larynx squamous carcinoma cell lines (Hep-2 and Hep-2R), with different radiosensitivities in vitro were explored in the present study. Based on previous research, elevated POT1 and TPP1 expressions were detected by reverse transcription-PCR and Western blotting in Hep-2R cell lines. Furthermore, Hep-2R cells showed increased recovery ratio accompanied by a reduction of cell arrested in G2/S phase, suggesting that the radioresistance of Hep-2R cells was due to a faster growth in which telomere length had recently been demonstrated to be a powerful prognostic marker. These results manifest that radioresistant Hep-2R cell lines showed certain changes in gene expression and bionomical profiles that are different from the profile changes of the more-sensitive Hep-2 cell lines, and that evaluation of telomere-associated genes may be a prognostic marker for response to radiotherapy in larynx squamous cell carcinoma (LSCC).