Polymerase chain reaction-based enzyme immunoassay for quantitation of telomerase activity: Application to colorectal cancers

Telomerase is a specialized reverse transcriptase that synthesizes telomeri c sequences onto human chromosomal ends, It appears to be present in the ma jority of primary human cancer tissues, and may have potential as a univers al tumor marker. In this report, ne describe a sensitive, non-radioactive, polymerase chain reaction (PCR)-based enzyme immunoassay (EIA) for the quan titation of telomerase activity in human cells. This PCR-EIA is convenient and can be easily completed within 3 h, The correlation coefficient between the results of PCR-EIA and the conventional telomeric repeat amplification protocol (TRAP) method, as measured on 4 different cell lines, was over 0. 98, Evaluation of this method for clinical application was conducted with t issues obtained from patients with colorectal cancers and the results were compared with those of the conventional TRAP method. Our data indicate that telomerase activities measured by conventional TRAP and PCR-EIA are highly correlated, and we suggest that the PCR-EIA method can substitute for conv entional TRAP.