MiR-202-3p functions as a tumor suppressor and reduces cell migration and invasion in papillary thyroid carcinoma.

OBJECTIVE: MicroRNAs (miRNAs) are recently identified as key regulators of tumor development and progression. MiR-202-3p functions as tumor suppressor in some cancer types. The aim of the study is to determine its expression pattern and explore the functions underlying the mechanism of miR-202-3p in papillary thyroid carcinoma (PTC).

PATIENTS AND METHODS: By using quantitative RT-PCR (QRT-PCR) analyses, we detected miR-202-3p expression in PTC tissues and cell lines. Transwell migration and invasion assays were performed to measure the migration and invasion ability of tumor cells transfected with miR-202-3p mimic. Western blot analysis was used to detect the protein expression.

RESULTS: Our results showed that miR-202-3p expression was frequently downregulated in 96 cases PTC tissues compared to adjacent normal tissues. Lower expression of miR-202-3p associated with lymph node metastasis of patients with PTC. Overexpression of miR-202-3p inhibited cell migration and invasion in TPC-1 and BCPAP cells. Furthermore, enforced expression of miR-202-3p inhibited WNT signaling by downregulating β-catenin expression in TPC-1 and BCPAP cells.

CONCLUSIONS: Our findings indicated that miR-202-3p may represent a novel therapeutic target of in PTC.