Background: The reactivation of the telomerase seems to be an important step in the carcinogenesis of most human cancer types. Cell clones, which express this enzyme, get the ability of indefinite proliferation, means become immortal.

Methods: In this study, 80 patients with squamous cell carcinomas (SSC) in oral cavity, oropharynx, hypopharynx and larynx were recorded prospectively concerning a possible correlation of telomerase activity and clinical and prognostic factors. Telomerase activity was analysed by a modified telomeric repeat amplification protocol (TRAP) assay.

Results: In 75% of the tumour tissues the telomerase was demonstrated independently of the localization of the tumour. The known clinical prognostic factors did not show any correlation to the expression rate of the telomerase activity in the tumour tissues. Also, reactivated telomerase did not affect the tumour-dependent survival. Only the number of lymph node metastases was in tendency higher in patients with telomerase-positive tumours. The number and timeframe of local and regional recurrences was not influenced by the telomerase status.

Conclusions: Although telomerase seems to be an important part of the carcinogenesis of SCC our data show that the reactivation of telomerase in tumour tissue did not have any prognostic significance for these tumours. The tendency that tumours with active telomerase developed lymph node metastases in a higher number should be evaluated by further enlarged studies for its clinical relevance.

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http://dx.doi.org/10.1111/j.1600-0714.2004.00232.xDOI Listing

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