Telomerase hTR and hTRT gene expression in oral precancerous lesions and squamous cell carcinomas.

OBJECTIVE

To investigate the expression of telomerase genes in oral precancerous lesions and squamous cell carcinomas and to research the relationship between telomerase gene expression and carcinogenesis of oral mucosa epithelium.

MATERIALS AND METHODS

Eighty two cases were detected for hTR and hTRT gene by in situ hybridization techniques--7 cases of normal oral mucosa, 7 cases of hyperplasia lesions, 30 cases of oral precancerous lesions (dysplasia lesions), 8 cases of oral mucosa carcinomas in situ, and 30 cases of oral squamous cell carcinomas.

RESULTS

Weaker signals of hTR and hTRT gene expression were observed in normal oral epithelia and hyperplasia lesions; hTR and hTRT were positive 28.6% (4 of 14) and 21.4% (3 of 14), respectively. The expression of telomerase genes in the precancerous lesions became stronger due to phenotypic progression and the increasing degree of dysplasia; hTR and hTRT were positive 60.0% (18 of 30) and 46.7% (14 of 30), respectively. Stronger hTR and hTRT expressions were observed in squamous cell carcinoma, with an equal positivity of 81.6% (31 of 38).

CONCLUSION

Telomerase gene expression is closely related to the malignant degree of oral mucosa. Telomerase is reactivated frequently during late stages of oral precancerous lesions and may play a crucial role in progression of oral cancer.