miR-181a and miR-203 inhibit migration and invasion of laryngeal carcinoma cells by interacting with ATF2.

MicroRNAs (miRNAs) have been recognized to modulate the progression of tumorigenesis by serving as oncogenes or tumor suppressors. Despite the involvement of miR-181a and miR-203 in several cancers as has been substantiated, their roles in laryngeal carcinoma (LC) remain unclear. In this study, the abundances of miR-181a, miR-203 and activating transcription factor 2 (ATF2) mRNA in LC cell lines were detected by RT-qPCR. Western blot was performed to detect the protein levels of N-cadherin, E-cadherin and ATF2. Cell migration and invasion ability were assessed by Trans-well assay. The putative binding sites between miR-181a or miR-203 and ATF2 were predicted using Bioinformatics software and further validated by Dual-Luciferase reporter and RNA immunoprecipitation (RIP) assays. Results showed reduced abundances of miR-181a and miR-203 in LC cell lines. Introduction of miR-181a or miR-203 reduced cell migration and invasion, which was further confirmed by the reduction of N-cadherin and increase of E-cadherin in LC cells. ATF2 was identified to be a potential target of miR-181a and miR-203. Absence of ATF2 overturned the stimulatory effects of anti-miR-181a and anti-miR-203 on cell migration and invasion in LC cells. Our findings suggested that miR-181a and miR-203 attenuated cell migration and invasion ability by directly targeting ATF2 in LC, providing novel insight into the regulatory mechanisms of miR-181a and miR-203 in LC.