Associations of miR-146a and miR-146b expression and clinical characteristics in papillary thyroid carcinoma.

BACKGROUND

Human miRNAs have emerged as potentially useful diagnostic and prognostic markers in cancer within the past decade. Abnormal expression of microRNA-146 (miR-146) has been found in several classes of cancers.

OBJECTIVE

To explore expression and clinical associations of miR-146a and miR-146b in papillary thyroid carcinoma.

METHODS

We investigated expressions of miR-146a and miR-146b in tissues and peripheral blood among 128 patients with primary PTC, 120 patients with nodular goiter and 120 healthy controls by RT-PCR. Furthermore, the associations between the miR-146a and miR-146b expression and clinical parameters of PTC were analyzed.

RESULTS

Levels of miR-146a and miR-146b expression in PTC tissues were higher compared to the nodular goiter tissues (P=0.014 and 0.001) and perineoplastic thyroid tissues (P=0.023 and 0.002). Positive associations were found between levels of miR-146a expression in PTC tissues and gender (female), cervical lymph node metastasis, multifocality, extra tyroidal invasion and advanced clinical TNM stages (III and IV). For miR-146b, there were positive association between levels of miR-146b expression and female, extra tyroidal invasion and advanced clinical TNM stages.

CONCLUSIONS

Up-regulation of miR-146a and miR-146b expression in tissues was related to carcinogenesis and deterioration of PTC. MicroRNA-146a and miR-146b expressed in thyroid tissue may act as potential biomarkers for PTC patients.