Relation Between Iodide Transporters and Thyroid Diseases / 中国普外基础与临床杂志

ABSTRACT

Objective To investigate the clinical significance of the three iodide transporters in thyroid diseases. Methods Literatures about the Na+/I-symporter (NIS), pendrin and human apical iodide transporter (hAIT) in recent years were reviewed and their expressions in different thyroid diseases were also analyzed. Results NIS proteins express at the basolateral membrane of thyrocytes in normal thyroid tissue, while pendrin and hAIT proteins are limited to the apical membrane of thyrocytes lining in the follicular lumen. In the tissues of thyroid carcinomas, it was found that the NIS proteins expressed in the cytoplasm and their expressions decreased; The mutation of NIS gene may be one of the main causes of congenital hypothyroidism. The expression of prendrin protein may be related to the function of follicles: its expression level increased significantly both in Graves diseases and toxic adenomas, but significantly decreased in differentiated thyroid carcinoma. However, the correlation between the decrease and the degrees of differentiation of carcinoma cell line are still disputable. The expression of hAIT protein does not significantly altered in hyperfunctioning tissues. It only slightly decreased occasionally in hypofunctioning adenomas, but it decreased significantly in thyroid carcinomas. Conclusion The abnormal expressions of the three iodide transporters may be related closely with the type of thyroid diseases. However, their pathogenic mechanisms and the causes of their abnormal expression are still unknown, which need to be studied further.