Clinical significance and usefulness of quantification of telomerase activity in oral malignant and nonmalignant lesions.

We quantified telomerase activity (TA) in patients with oral and maxillofacial malignant and nonmalignant lesions, and compared it with their clinical status and grade of malignancy. Fifty-two malignant and 52 nonmalignant lesions were analyzed. All malignant lesions were pathologically diagnosed as oral squamous cell carcinoma (OSCC). Normal gingival tissue served as a control. These specimens were obtained by biopsy or surgical resection, and stored at -80 degrees C until use. TA was quantified by a fluorescence-based TRAP method. TA levels ranged from 0.00 to 95.24 (average 33.24)U/microgP in 52 malignant lesions, and from 0.00 to 79.35 (average 11.91)U/microgP in 52 nonmalignant lesions (P < 0.0001). TA was detected in 96.2% of malignant and 65.4% of nonmalignant lesions. There was no relationship between TA levels and clinical stages or YK classification. However, under WHO classification, there were significant differences (P < 0.05) between Grades I and III or II + III. Among nonmalignant lesions, epithelial dysplasia showed a significantly higher TA level than that of oral lichen planus (P < 0.05) and other benign lesions (P < 0.0001). Oral lichen planus also significantly differed from other benign lesions (P < 0.05). These results suggest that TA is related to the histological grade of malignancy, and is also useful as a prognostic predictor for precancerous lesions and conditions.