title: Pendrin expression in nodular and non-nodular thyroid tissues.
abstract: BACKGROUND
  Different mechanisms for the expression of pendrin which is an apical iodide transporter have been reported in nodular thyroid tissues compared to normal thyroid. The aim of the present study was to determine the alterations of pendrin expression in nodular and surrounding non-nodular thyroid tissues and clarify the role of pendrin in the functional behaviour of nodular lesions.
  
  
  METHODS
  Twenty-six nodular and paired non-nodular normal thyroid tissues were collected at the same centre. Patients were divided into two groups based on the function of the dominant thyroid nodule; hot nodules (n = 18) and cold nodules (n = 8). mRNA levels of pendrin were evaluated by quantitative RT-PCR. Pendrin protein expression was determined by immunohistochemical analysis. Results of dominant nodules were compared to non-nodular thyroid tissue of the same patient.
  
  
  RESULTS
  No statistically significant difference was found with respect to qualitative and quantitative measurements of pendrin expression between hot and cold nodules. However, percent immunohistochemical staining of pendrin was significantly higher in both hot and cold nodules compared to non-nodular thyroid tissue of the same patients. RT-PCR revealed comparable mRNA levels of pendrin gene between hot nodules and corresponding normal thyroid tissues. However, in cold nodules, significantly decreased mRNA levels of pendrin were observed compared to normal thyroid tissue. mRNA levels of pendrin showed significant positive correlation with TSH in corresponding non-nodular thyroid tissues.
  
  
  CONCLUSIONS
  The present study demonstrates that expression of pendrin could not be influenced by TSH in thyroid nodules and expression level of pendrin seems not to have an effect on nodule function.
authors.affiliation: Department of Endocrinology and Metabolism, Istanbul University, Faculty of Medicine, Istanbul, Turkey.
authors.forename: Berna
authors.initials: B
authors.lastname: Temel
authors.forename: Nurdan
authors.initials: N
authors.lastname: Gul
authors.forename: Faruk
authors.initials: F
authors.lastname: Kutluturk
authors.forename: Yersu
authors.initials: Y
authors.lastname: Kapran
authors.forename: Sema
authors.initials: S
authors.lastname: Sirma
authors.forename: Duran
authors.initials: D
authors.lastname: Ustek
authors.forename: Fatih
authors.initials: F
authors.lastname: Tunca
authors.forename: Yasemin
authors.initials: Y
authors.lastname: Giles
authors.forename: Faruk
authors.initials: F
authors.lastname: Alagol
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007454:Iodides / Q000378:metabolism; D017136:Ion Transport / Q000502:physiology; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D000076988:Sulfate Transporters; D013961:Thyroid Gland / Q000378:metabolism*; D016606:Thyroid Nodule / Q000235:genetics / Q000378:metabolism*
chemical_list: D007454:Iodides; D026901:Membrane Transport Proteins; D012333:RNA, Messenger; C085609:SLC26A4 protein, human; D000076988:Sulfate Transporters