Localization of telomerase hTERT protein and hTR in benign mucosa, dysplasia, and squamous cell carcinoma of the cervix

Telomerase has been detected by telomerase repeat amplification protocol (T RAP) assay in cervical dysplasia and squamous cell carcinoma but not in mos t normal cervical tissues. In the present study: the cellular localization of the protein catalytic subunit of telomerase (hTERT) and the RNA componen t (hTR) were investigated by a sensitive immunohistochemical technique and by in situ hybridization, respectively hTERT protein was detected in all di agnostic categories of cervical specimens, hTERT was localized predominantl y to the lower suprabasal levels of normal squamous mucosa but was detected throughout virtually all levels of the lesional epithelium in low-grade sq uamous intraepithelial lesions (LSILs), high-grade squamous intraepithelial lesions (HSILs), and squamous cell carcinoma (SCC), Telomerase expression correlated with hTERT detection in SCC and HSIL but was not detected by TRA P assay in most samples of normal mucosa or LSIL. The distribution of hTR c orrelated with the localization of hTERT in HSIL and SCC but was restricted to the basal and suprabasal cell layers in normal mucosa and LSIL.