Telomerase activity in Indian patients with carcinomas of the aerodigestive tract.

The activation of telomerase, a ribonucleoprotein maintaining telomeric length, might represent an additional required event in the multigenetic process of tumorigenesis in human cancer. To investigate whether telomerase activity is a prerequisite or a useful indicator of malignant potential, we assayed the enzyme in squamous cell carcinomas and tried to observe any correlation with clinical staging and histopathological grading. We have studied telomerase activity in 23 samples of squamous cell carcinomas of the aerodigestive tract and in 22 corresponding samples of adjoining tissues using the telomerase repeat amplification assay. Telomerase activity was detected in 100% of the tumor samples studied. The telomerase activity increased with tumor grading, but was not statistically significant. Low levels of enzyme activity were also detected in 60.86% of the adjoining normal tissue samples. Reactivation of telomerase may play an important role in the carcinogenesis of aerodigestive tract tumors. Detection of enzyme activity in the adjoining normal tissue is suggestive of microinvasion of tumor cells and/or early activation of telomerase in the progression towards cancer, before possible pathological identification.