Resumen

MARRERO RODRIGUEZ, María Teresa. Methylation of the thyroid stimulating hormone receptor: diagnostic marker of malignity in thyroid cancer. Rev Cubana Endocrinol [online]. 2007, vol.18, n.3. ISSN 1561-2953.

The methylation state of the gene promoter for the receptor of the thyroid stimulating hormone (TSH) in the diagnosis of thyroid tumors of epithelial origin was analyzed. The study was conducted in thyroid tissue obtained from paraffin blocks of different thyroid pathologies (papillary, follicular and undifferentiated carcinoma and follicular adenomas). The work was done by using the DNA modification technique with sodium bisulfite, and polymerase chain reaction was applied to analyze the gene methylation state. Methylation of the promoter for the gene of the TSH receptor was found in the papillary carcinomas (33 of 40; 82.5 %), in 10 undifferentiated carcinomas (100 %), and in 10 of the 15 follicular carcinomas analyzed (66.6 %). No methylation was observed in the 8 follicular adenomas under study. The methylation of the gene for the TSH receptor was proposed as a new diagnostic marker of malignity and as a basis for using demethylating agents together with radioiodine therapy in patients with thyroid cancer of epithelial origin that do not respond to therapy. 

Palabras clave : Methylation; gene; DNA; thyroid cancer.