Regulation of β-catenin-mediated esophageal cancer growth and invasion by miR-214

The malignancy of esophageal cancer (EC) is largely due to its fast growth and invasion, in which WNT/β-catenin signaling plays a critical role. Hence, suppression of β-catenin signal transduction in EC cells may inhibit cancer growth and metastases. Among all microRNAs (miRNAs), miR-214 has been shown as a tumor suppressor in many cancers, but has yet studied in EC. Here we found that EC specimens had significant higher levels of β-catenin, and significantly lower levels of miR-214, compared to paired non-EC tissue. The levels of β-catenin and miR-214 were inversely correlated in EC specimens. Bioinformatics analyses showed that miR-214 bound to 3'-UTR of β-catenin mRNA in EC cells to inhibit its translation. Overexpression of miR-214 decreased β-catenin protein, while depletion of miR-214 increased β-catenin protein in EC cells, without altering β-catenin mRNA levels. Overexpression of miR-214 in EC cells inhibited cell growth and invasion, while depletion of miR-214 in EC lines increased cell growth and invasion. Taken together, our data demonstrate a previously unappreciated role for miR-214 in suppression of β-catenin-mediated EC cell growth and invasion, and highlight miR-214 as a potent suppressor of EC.