Quantitative detection of telomerase activity by real-time TRAP assay in the body fluids of cancer patients

Int J Mol Med. 2005 Nov;16(5):857-63.


Real-time TRAP assay was developed to improve the sensitivity and quantitative detection of telomerase activity in the body fluids of cancer patients. The sensitivity and clinical significance of the real-time TRAP assay was investigated. Real-time PCR protocol was modified by using ACX primer and SYBR green mixture from the process of TS primer extension. Real-time TRAP showed high correlation (r2=0.843, p=0.001) and sensitivity (25 times higher) compared to conventional TRAP. Of 164 samples, there were 8 positives in cytology (4.9%), 7 (4.3%) using the conventional TRAP, and 41 (25%) using real-time TRAP. In cytology positive samples, real-time TRAP showed a higher positivity than conventional TRAP (75% vs 63%) suggesting a higher sensitivity in the body fluids. There was a tendency towards a longer progression-free duration in telomerase negative patients than in positive patients, as determined by conventional and real-time TRAP. The diagnostic interval between the first positivity documentation and clinical progression was short in the order of real-time TRAP, conventional TRAP and cytology. In conclusion, real-time TRAP assay can detect telomerase activity at an earlier phase of cancer progression and can replace conventional TRAP assay for detecting the telomerase activity in body fluids.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Body Fluids / chemistry*
  • Humans
  • Neoplasms / diagnosis*
  • Neoplasms / enzymology
  • Polymerase Chain Reaction / methods*
  • Sensitivity and Specificity
  • Telomerase / analysis*
  • Telomerase / genetics
  • Telomerase / metabolism
  • Tumor Cells, Cultured


  • Telomerase