Implications of Na+/I- Symporter Transport to the Plasma Membrane for Thyroid Hormonogenesis and Radioiodide Therapy

MARTÍN, MARIANO; GEYSELS, ROMINA CELESTE; PEYRET, VICTORIA; BERNAL BARQUERO, CARLOS EDUARDO; MASINI-REPISO, ANA MARÍA; NICOLA, JUAN PABLO

Journal of the Endocrine Society

Oxford Academic

Año: 2019 vol. 3 p. 222 - 222

odine is a crucial component of thyroid hormones; therefore, a key requirement for thyroidhormone biosynthesis is that iodide (I ) be actively accumulated in the thyroid follicular cell. The ability of the thyroid epithelia to concentrate I is ultimately dependent on functional Na+/ I Symporter (NIS) expression at the plasma membrane. Underscoring the significance of NIS for thyroid physiology, loss-of-function mutations in NIS-coding SLC5A5 gene cause I transport defect resulting in dyshormonogenic congenital hypothyroidism. Moreover, I accumulation in the thyroid cell constitutes the cornerstone for radioiodide ablation therapy for differentiated thyroid carcinoma. However, differentiated thyroid tumors often exhibit reduced (or even undetectable) I transport compared to normal thyroid tissue, and are diagnosed as cold nodules on thyroid scintigraphy. Paradoxically, immunohistochemistry analysis revealed that most cold thyroid nodules express none, normal, and even higher NIS