Quantitative assay of telomerase activity in head and neck squamous cell carcinoma and other tissues

Objectives: To confirm the applicability and use of a new technique to dete ct and quantify telomerase activity of specimens from head and neck maligna nt neoplasms and to explore whether the levels of telomerase activity can b e a useful marker for cancer risk assess ment in head and neck malignant ne oplasms. Design: Ninety-six specimens from 39 patients with head and neck malignant neoplasms were obtained. The specimens included 39 from patients with prima ry tumors (25 with head and neck squamous cell carcinoma and 14 with others ), 10 from patients with neck metastases, 10 from patients with dysplasias, and 37 from patients with normal tissue. HeLa cell lines were used as posi tive control samples. Main Outcome Measure: The levels of telomerase activity were determined usi ng a liquid scintillation counter. Results: The new method has a high rate of outcome reproducibility. The int rabatch and extrabatch variations were 15.6% and 16.4%, respectively. The l inear relationship was good between the telomerase activity and the value w ithin 700 radioactive cpm (rcpm) to approximately 7000 rcpm. The levels of telomerase activity determined by radioactive count were more than 1000 rcp m in 42 of the 49 malignant specimens and much more than that in the normal tissues, with the exception of 3 specimens. The levels of telomerase activ ity in normal tissues were less than 1000 rcpm in every sample and less tha n that in the malignant neoplasm samples, with the exception of 1 specimen (P < .000). Higher levels of telomerase activity in 2 of 10 tissues from pa tients who had dysplasias were detected (2 specimens from patients who had severe dysplasia), The differences in the levels of telomerase activity bet ween the head and neck squamous cell carcinomas and the other tumors were n ot statistically significant (P>.05). Conclusions: Detection of telomerase activity in head and neck malignant ne oplasms can be a useful marker for the assessment of cancer. Telomerase rea ctivation may play an important role in tumorigenesis in head and neck squa mous cell carcinoma. The quantification of telomerase activity may have cli nical diagnostic value for head and neck malignant neoplasms.