Detection of telomerase activity in prostatic fluid specimens

We report here the extended use of the telomeric repeat amplification proto col (TRAP) assay for the detection of telomerase activity in fresh prostati c fluid obtained from anesthetized patients. Telomerase activity was detect ed in pellet extract and/or supernatant fluid of specimens obtained from 25 of 30 prostate cancer (PCa) patients (83%), whereas no activity was simila rly detectable in specimens taken from 8 of 9 patients (89%) without clinic al evidence of PCa. The positive predictive value (PPV) of the TRAP assay f or PCa in this pilot study was 96%. We found a strong correlation between t elomerase activity in prostatic fluid specimens and serum prostate specific antigen (PSA) values. Telomerase activity was found in 84% of specimens fr om patients with PSA values >4 ng/ml, whereas in specimens from patients wi th PSA values less than or equal to4 ng/ml. only 29% tested positive for te lomerase activity. In patients with PSA values above the standard 0 to 4 ng /ml reference range, the PPV of the TRAP assay was 84%. Furthermore, telome rase activity could be detected in 85% of the specimens from PCa patients w ith Gleason scores >4. In prostatic fluid from PCa patients with Gleason sc ores of less than or equal to4, telomerase activity was detected 50% of the time. The PPV was 92% when a Gleason score of 4 was used as the lower limi t. This pilot study raises the possibility of utilizing telomerase activity as an aid in PCa detection. (C) 2000 Elsevier Science Inc. All rights rese rved.