Quantitative telomerase activity in malignant, benign and normal gynecological tissues

Department of Obstetrics and Gynecology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
European journal of gynaecological oncology (Impact Factor: 0.61). 01/2005; 26(1):83-6.
Source: PubMed


The aim of this study was to evaluate quantitative telomerase activity in malignant, benign and normal gynecological tissue samples by using the Telomerase-PCR ELISA kit, and to determine a cut-off level for malignancy by this quantitative method.
Fifty gynecological tumors, 27 benign gynecological disorders and 29 normal tissues were analyzed by the Telomerase-PCR ELISA kit. All tissues were confirmed by a pathologist. A ROC (receiver operator characteristic) curve was drawn to determine a threshold level best discriminating malignant tissues from benign pathologies and normal tissues. Telomerase activity was compared in malignant, benign and normal tissues.
The mean level of telomerase activity of the malignant tumor samples (1.03 +/- 0.53 units) was significantly (p < .001) higher than the normal tissues (0.13 +/- 0.07 units) and benign pathologies (0.37 +/- 0.25 units). The cut-off point to differentiate malignant samples from benign samples was set at 0.42 units, where the sensitivity was 93.8% and the specificity was 89.3%. Positive predictive value was 84% and negative predictive value was 89.3%. There was a significant difference in telomerase activity between malignant, benign and normal tissues within each histological group.
In this preliminary study, the telomerase-PCR ELISA method was found to have a high sensitivity and specificity to differentiate malignant gynecological tissues from benign tissues.

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