The Status of Telomerase Enzyme Activity in Benign and Malignant Gynaecologic Pathologies

Abstract

Background: Telomeres are essential for the function and stability of eukaryotic chromosomes. Telomerase consists of three subunits: human telomerase reverse transcriptase (hTERT), human telomerase RNA (hTR), and telomerase protein 1 (TP1). The hTERT subunit determines the activity of telomerase as an enzyme and is detected in most human tumors and regenerative cells. Telomerase activity is a useful cancer-cell detecting marker in some types of cancers.Aims: The aim of this study was to assess of telomerase hTERT mRNA in gynaecological tumors for diagnosis of malignancy.Study Design: Cross-sectional study.Methods: A total of 55 gynaecologic tumor samples (35 ovarian, 13 endometrial, 6 cervical and 1 placental site trophoblastic tumor tissue) were obtained at the time of surgery. Quantification of hTERT mRNA was performed in a real-time reverse transcriptase polymerase chain reaction (RT-PCR) using the LightCycler TeloTAGGG hTERT Quantification Kit.Results: It was histopathologically detected that 18 of the tissue samples were malignant and 37 of the samples were benign. 16 of the malignant tissue samples (88.9%) and 3 (8.1%) (endometrial tissue in proliferative phase, mucinous cyst adenoma and endometriosis) of the benign tissue samples were found to be hTERT positive. With the presence of these data, sensitivity and specificity of hTERT for the diagnosis of malignancy were calculated to be 88.9% and 91.9%, respectively. Conclusion:It was suggested that the measurement of telomerase activity in gynaecologic tumors, except for endometrial tissue in the reproductive phase, is a valuable method for pathological investigation.

Telomerase and Telomeres in Endometrial Cancer

“…The authors also noted that telomerase activity was increased by estrogen which induced cell proliferation and was reduced in progesterone dominant conditions, indicative of an ovarian steroid hormonal regulation. The finding of high telomerase activity in endometrial cancers has been subsequently confirmed by many other groups (15, 25, 159, 239, 247, 267–269). In addition to the high telomerase activity measured by the gold standard test, the TRAP assay, some authors studied expression levels of components of the telomerase holoenzyme using qPCR to detect gene expression levels.…”

Telomere and Telomerase-Associated Proteins in Endometrial Carcinogenesis and Cancer-Associated Survival

“…Previous research has demonstrated high telomerase activity in the premenopausal endometrium, with a transition to low or undetectable levels in the postmenopausal endometrium [ 36 , 38 , 39 ]. Despite unique endometrial telomerase biology, there is reactivation of telomerase activity from the postmenopausal state to EC [ 28 , 29 , 35 , 40 ]. Hence, telomerase must factor in the malignant transformation of the endometrium.…”