MicroRNA-106b regulates the tumor suppressor RUNX3 in laryngeal carcinoma cells.

Our study focuses on a set of laryngeal tumors that show reduced RUNX3 expression in the absence of transcriptional silencing of tumor suppressor gene RUNX3 by aberrant methylation of CpG islands. We report that the loss of expression of RUNX3 correlates with up-regulation of miR-106b in human laryngeal carcinoma tissue. The downregulation of RUNX3 is mediated by miR-106b through binding of its 3'UTR. Moreover, miR-106b can promote the proliferation and invasion of laryngeal carcinoma cells by directly targeting RUNX3, and RUXN3 knockdown can abolish this phenotype. These results shed a new insight into the mechanism of miRNA regulation in laryngeal carcinoma.