Telomerase and telomere length in normal and malignant human endometrium as prognostic markers

Telomerase activation and telomere length maintainence are thought to be essential for cellular immortality and oncogenesis. Normal human endometrium expresses significant telomerase activity in a menstrual phase dependent manner. In this report, we have evaluated telomerase activity and telomere length in post menopausal endometrial hyperplasias and endometrial cancers to study their usefulness as prognostic markers. Telomerase activity was measured by the TRAP assay (Boehringer Mannheim, Germany) and telomere restriction fragment (trf) by the telomere length assay kit (BD Pharmingen). Proliferation markers PCNA and Bcl2 were studied by immunohistochemistry. Senescence associated Ogal activity was studied simultaneously and correlated with the above markers. Strong telomerase activity was observed in the proliferative phase of the normal endometrium, endometrial cancers and post-menopausal endometrial hyperplasias compared to normal, secretory and resting phases of the endometrium. PCNA and Bcl2 showed high positivity in telomerase positive cases. Telomerase activity was inversely proportional to Ogal activity. Mean trf lengths became shortened as the normal tissues underwent neoplastic changes. Our study suggests that high telomerase activity and short telomere lengths could be useful prognostic markers in human endometrium.