Expression of the Na+/I- symporter gene in human thyroid tumors: a comparison study with other thyroid-specific genes

J Clin Endocrinol Metab. 1999 Sep;84(9):3228-34. doi: 10.1210/jcem.84.9.5996.


The expression of 4 thyroid tissue-specific genes [Na+/I- symporter (NIS), thyroid peroxidase (TPO), thyroglobulin (Tg), TSH receptor (TSH-R)] as well as of the glucose transporter type 1 (Glut1) gene was analyzed in 90 human thyroid tissues Messenger ribonucleic acids were extracted from 43 thyroid carcinomas (38 papillary and 5 follicular), 24 cold adenomas, 5 Graves' thyroid tissues, 8 toxic adenomas, and 5 hyperplastic thyroid tissues; 5 normal thyroid tissues were used as reference. A kinetic quantitative PCR method, based on the fluorescent TaqMan methodology and real-time measurement of fluorescence, was used. NIS expression was decreased in 40 of 43 thyroid carcinomas (10- to 1200-fold) and in 20 of 24 cold adenomas (2- to 700-fold); it was increased in toxic adenomas and Graves' thyroid tissues (up to 140-fold). TPO expression was decreased in thyroid carcinomas, but was normal in cold adenomas; it was increased in toxic adenomas and Graves' thyroid tissues Tg expression was decreased in thyroid carcinomas, but was normal in the other tissues. TSH-R expression was normal in most tissues studied and was decreased in only some thyroid carcinomas. In thyroid cancer tissues, a positive relationship was found between the individual levels of expression of NIS, TPO, Tg and TSH-R. No relationship was found with the age of the patient. Higher tumor stages (stages >I vs stage I) were associated with lower expression of NIS (P = 0.03) and TPO (P < 0.01). Expression of the Glut1 gene was increased in 1 of 24 adenomas and in 8 of 43 thyroid carcinomas. In 6 thyroid carcinoma patients, 131I uptake was studied in vivo; NIS expression was low in all samples; 3 patients with normal Glut-1 gene expression had 131I uptake in metastases, whereas the other 3 patients with increased Glut-1 gene expression had no detectable 131I uptake. In conclusion, this study shows 1) a reduced expression of NIS gene in most hypofunctioning benign and malignant thyroid tumors; 2) a differential regulation of the expression of thyroid-specific genes; 3) an increased expression of Glut-1 gene in some malignant tumors that may suggest a role for glucose derivative tracers to detect in vivo thyroid cancer metastases by positron emission tomography scanning.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma, Follicular / genetics
  • Adenoma / genetics
  • Adult
  • Carcinoma, Papillary / genetics
  • Carrier Proteins / genetics*
  • Female
  • Gene Expression*
  • Glucose Transporter Type 1
  • Graves Disease / genetics
  • Humans
  • Iodide Peroxidase / genetics
  • Kinetics
  • Male
  • Membrane Proteins / genetics*
  • Middle Aged
  • Monosaccharide Transport Proteins / genetics
  • Polymerase Chain Reaction
  • RNA, Messenger / analysis
  • Receptors, Thyrotropin / genetics
  • Symporters*
  • Thyroglobulin / genetics
  • Thyroid Neoplasms / metabolism*


  • Carrier Proteins
  • Glucose Transporter Type 1
  • Membrane Proteins
  • Monosaccharide Transport Proteins
  • RNA, Messenger
  • Receptors, Thyrotropin
  • SLC2A1 protein, human
  • Symporters
  • sodium-iodide symporter
  • Thyroglobulin
  • Iodide Peroxidase