Expression of pendrin in benign and malignant human thyroid tissues

Abstract

The Pendred syndrome gene (PDS) encodes a transmembrane protein, pendrin, which is expressed in follicular thyroid cells and participates in the apical iodide transport. Pendrin expression has been studied in various thyroid neoplasms by means of immunohistochemistry (IHC), Western blot and RT -quantitative real-time PCR. The expression was related to the functional activity of the thyroid tissue. Follicular cells of normal, nodular goitre and Graves' disease tissues express pendrin at the apical pole of the thyrocytes. In follicular adenomas, pendrin was detected in cell membranes and cytoplasm simultaneously in 10 out of 15 cases. Pendrin protein was detected in 73.3 and 76.7% of the follicular (FTC) and papillary (PTC) thyroid carcinomas, respectively, where pendrin was solely localised inside the cytoplasm. An extensive intracellular immunostaining of pendrin was observed in six out of 11 (54.5%) of positive FTCs and 19 out of 23 (82%) of PTCs. Focal reactivity was detected in one follicular-and three papillary carcinomas, whereas pendrin protein was absent in three of 15 FTC and four of 30 PTC; mRNA of pendrin was detected in 92.4% of thyroid tumours. The relative mRNA expression of pendrin was lower in cancers than in normal thyroid tissues (Po0.001). The pendrin protein level was found to parallel its mRNA expression, which was not, however, related to the tumour size and tumour stage. In conclusion, pendrin is expressed in the majority of differentiated thyroid tumours with high individual variability but its targeting to the apical cell membrane is affected.

SLC26A4 expression among autoimmune thyroid tissues

“…In thyroid tissues with HT, carcinoma and MNG, mRNA level was decreased compared to normal thyroid tissues. The reduction of the mRNA level in carcinoma was consistent with the previously reported works (Bidart et al, 2000;Arturi et al, 2001;Porra et al, 2002;Skubis-Zegadło et al, 2005). However, to our knowledge, the investigation of PDS gene among HT patient tissues has not been reported in the literature.…”

“…Several studies concerning the PDS gene and pendrin expressions in thyroid and kidney have been reported (Bidart et al, 2000;Arturi et al, 2001;Porra et al, 2002;Kondo et al, 2003;Skubis-Zegadło et al, 2005). However, a discrepancy was described considering RNA and protein levels correlations particularly among GD.…”

NrCAM, a neuronal system cell-adhesion molecule, is induced in papillary thyroid carcinomas

“…Real-time PCR was carried out using the double-stranded DNA-specific dye SYBR Green I. The reaction mixtures contained template cDNA, 12.5 ml 2X SYBR Green PCR Master Mix (PE Applied Biosystems, Foster City, CA, USA), and 50 nM primers (listed below) in a final volume of 25 ml (Mikula et al, 2003;Skubis-Zegadło et al, 2005). Amplification, data acquisition, and data analysis were carried out using the GeneAmp 7000 Sequence Detection System (PE Applied Biosystems).…”

Overexpression of Interleukin-4 in the Thyroid of Transgenic Mice Upregulates the Expression ofDuox1and the Anion Transporter Pendrin

“…The effects associated with uncontrolled ectopic production of IL-4 do not reflect the actual situation in GD patients who present with thyroid inflammation, TSHr-autoantibodies, and thyroid hyperstimulation; the latter would likely compensate for the IL-4-mediated Nis repression observed in the transgenic animals in the present study. In contrast, enhanced thyroid apical expression of pendrin was also reported in GD patients (83)(84)(85)(86). Moreover, autoantibodies against pendrin have been found in the sera of AITD patients, and SLC26A4 has been proposed to be a new AITD susceptibility gene (87,88).…”