Objectives: This study aimed to analyze both the level
and the cell site of the sodium-iodide symporter (NIS)
protein expression in autonomously functioning thyroid
nodules (AFTNs) and extranodular thyroid tissues. In
addition, this study sought to compare the clinical results
of patients with the levels of human NIS (hNIS) protein
Patients and Methods: The histological slides consisted
of 36 AFTNs and 31 extranodular thyroid tissues from
28 patients (5 males, 23 females; mean age 54.5±11.0
years; range 37 to 72 years) who underwent surgery for
toxic multinodular goitre. The expression of NIS protein
was investigated by immunohistochemistry in paraffinembedded
tissue sections using anti-hNIS monoclonal
antibody by the labeled streptavidin-biotin method.
Results: The percentage of hNIS positive follicular cells
was significantly higher in the AFTNs (13.33±12.09) than
in the extranodular thyroid tissues (1.35±3.03). Staining
for hNIS was mostly confined to the cell membrane in the
AFTNs (88.9%) and in the extranodular thyroid tissues
(54.5%). The clinical parameters and nodule volume did
not establish any correlation with hNIS immunoreactivity.
Conclusion: Our data indicate that functioning nodules
express higher amounts of NIS protein than the extranodular
thyroid tissue, but the level of hNIS immunoreactivity
was lower than had been reported in the previous
literature. This result may be due to interindividual variability
between different populations, and iodine status.
Furthermore, the localization of the NIS protein might not
give an indication of its functional status.
FREE FULL TEXTAnahtar Kelimeler: Genetik transkripsiyon; sodyum-iyot simporter;tiroid bezi/cerrahi; tiroid tümörleri.