THE EXPRESSION OF SODIUM IODIDE SYMPORTER (NIS) IN PAPILLARY THYROID CARCINOMAS

Voskoboynyk L.G., Bogdanova T.I., Romei C., Elisei R., Pinchera А.

Using immunohistochemical reaction with anti-NIS antibodies, 35 post-Chernobyl papillary thyroid carcinomas were studied. It was shown that in great majority of tumors (77,2%) the expression of NIS was not detected. It should be noted that in 5 of them the membrane positivity was detected in the foci of tumoral spreading but not in primary tumor Eight out of 35 (22,8%) were characterized by prominent increasing of NIS expression, but localization of protein was cytoplasm. The majority of these positive cases were presented by oxiphilic tumors or carcinomas with strong oxiphilic changes. There was not even one case of papillary thyroid carcinoma with prominent membrane localization of NIS in primary tumor. In conclusion, post-Chernobyl papillary thyroid carcinomas were characterized by low level of active NIS protein that could be due by reduction expression level of NIS or it’s translocation from membrane to cytoplasm.