Telomerase activity and hTERT mRNA expression in body fluids

Telomerase is a ribonucleoprotein enzyme associated with cellular immortality, and its activity is detectable in most human tumors and immortalized cells. In the present study, we examined telomerase activities and gene expression of human telomerase reverse transcriptase (hTERT) to detect malignant cells in body fluid. Twenty-eight cytological fluids were obtained from 28 patients, including 12 patients with benign cases and 16 patients with malignant tumors (14 ascitic fluids, 12 pleural fluids, 1 peritoneal washing, and 1 pericardial fluid). Telomerase activity was measured using a quantitative telomeric repeat amplification protocol (TRAP), and the hTERT messenger RNA (mRNA) expression was detected by reverse-transcription polymerase chain reaction (RT-PCR). Of the 16 malignant cases, telomerase activity was detected in 8 cases, and 10 cases involved expression of (hTERT) (mRNA). Neither telomerase activity nor hTERT mRNA expression was detected in benign cases. The telomerase activity and mRNA expression exhibited sensitivities of 50 and 62.5%, respectively, and both methods showed a specificity of 100%. The hTERT mRNA expression is a more sensitive marker than telomerase activity. Our results suggest that measurement of mRNA expression of hTERT in body fluid is useful as an adjunctive tool for cytological diagnosis.