Telomerase activity in primary prostate cancer

Purpose: Telomerase activity has been detected in a wide variety of human tumor types. We analyzed the telomerase activity in association with the acquisition of prostate cancer. Materials and Methods: Telomerase activity in prostate tissues was examined by PCR-based telomeric repeat amplification protocol (TRAP) assay. Results: Among 31 primary prostate cancers, 28 tissue samples (90%) displayed telomerase activity. The relative level of telomerase activity was associated with the pathological differentiation. High levels of telomerase activity were more frequently detected in poorly differentiated prostate cancer. None of the 10 samples taken from prostates with benign prostatic hyperplasia (BPH) or normal prostates expressed telomerase activity. In another 10 BPH samples obtained from prostate tissue adjacent to cancerous tissue, one of 10 samples (10%) showed weak telomerase activity. Furthermore we investigated this activity in human prostate cancer cell lines (PC-3, LNCaP, and DU145) and all showed very high activity compared to normal human tissue samples. Four lymph nodes and one bone metastasis also exhibited extremely high telomerase activity. Conclusions: The present results indicate that telomerase activity might be a marker for detecting malignancy of the prostate and evaluating the malignant potential of prostate cancer.