Differential expression of telomerase activity in human cervical cancer and cervical intraepithelial neoplasia lesions

Purpose: Telomeres are tandem arrays of repeated DNA sequences located at the ends of eukaryotic chromosomes, and ore synthesized by the enzyme telomerase. Loss of telomeric DNA may play on important role in the development of human cancers. However, very little is known about the status of telomerase during human cervical cancer development, Patients and Methods: Telomerase activity was measured by telomere repeat amplification protocol (TRAP) assay in 24 cervical cancers, one carcinoma in situ (CIS), and 20 cervical intraepithelial neoplasia (GIN) lesions, Adjacent nontumor cervical tissue from the same 24 cervical cancer patients and normal cervical tissues from 11 control individuals also were examined for the presence of telomerase activity. Results: Twenty two of the 24 (91.7%) cervical cancer specimens and the single CIS tissue were strongly positive for telomerase activity. Relatively weak but distinctive telomerase activity also was detectable in one of four GIN-I (25%), two of eight GIN-II (25%), and two of eight GIN-III (25%), respectively, However, telomerase activity wets not found in the 24 corresponding nontumor cervical tissues from the same cervical cancer patients and the 11 normal cervical tissues from control individuals, Conclusion: The majority of cervical cancers contain strong telomerase activity. Significant proportions of noncancerous GIN tissues also contain telomerase activity, although weaker than that in cervical cancer, It seems that there is a progressive increase of telomerase activity in association with an increased degree of cervical malignancy. These results seem to suggest that the expression of telomerase may play a crucial role in cervical cancer carcinogenesis, (C) 1997 by American Society of Clinical Oncology.