Telomerase activity in benign and malignant thyroid tumors

Area of Science:

• Endocrinology
• Oncology
• Molecular Biology

Background:

• Thyroid nodules are common, with a low malignancy risk, but lack complementary diagnostic tests.
• Fine-needle aspiration (FNA) cytology has limitations in preoperative diagnosis and risk stratification.
• Telomerase, active in malignant tissues and absent in normal adult tissues, presents a potential biomarker.

Purpose of the Study:

• To investigate telomerase activity in thyroid tumors and adjacent tissues.
• To assess the diagnostic and prognostic potential of telomerase activity in thyroid neoplasms.
• To explore the correlation between telomerase activity and tumor invasiveness.

Main Methods:

• Telomeric repeat amplification protocol (TRAP) assay was used on frozen tissue samples.
• Analyzed 24 thyroid tumors, 14 matched adjacent thyroid tissues, and 3 chronic thyroiditis samples.
• Compared telomerase activity with tumor invasiveness in papillary carcinomas.

Main Results:

• Telomerase activity detected in 11/20 thyroid carcinomas, including 10/14 papillary carcinomas and 1 Hurthle cell carcinoma.
• No telomerase activity found in benign adenomas, follicular, medullary, or anaplastic thyroid carcinomas.
• Telomerase activity observed in 3/14 adjacent thyroid tissues, associated with chronic inflammation, and in all 3 chronic thyroiditis samples.
• A significant correlation was found between telomerase activity and invasiveness in papillary thyroid carcinomas (6/7 invasive tumors were positive).

Conclusions:

• This is the first report of telomerase activity in thyroid tissue and nodules.
• Telomerase activity is prevalent in papillary thyroid carcinomas, absent in benign adenomas and most normal thyroid tissue.
• Telomerase activity may serve as a diagnostic and prognostic marker for thyroid neoplasms, potentially correlating with invasiveness.