Aberrant expression of miR-196a in gastric cancers and correlation with recurrence

MicroRNAs (miRNAs) are short noncoding RNAs (approximate to 22 nt) that play important roles in the pathogenesis of human diseases by negatively regulating gene expression. Here, we examined the relationship between miR-196a and gastric cancer. By the analysis of 72 gastric cancer samples, we found that the expression level of miR-196a microRNA significantly increased in primary gastric cancer tissues versus adjacent normal tissues. In addition, extracellular miR-196a detected in conditioned medium was strongly correlated with its cellular expression status and increased circulating miR-196a in patient serum was associated with gastric cancer disease status and relapse. Furthermore, ectopic expression of miR-196a microRNA promoted the epithelial-mesenchymal transition and migration/invasion capabilities of transfected cells, suggesting its oncogenic potential in gastric cancer progression. Altogether, our data demonstrate that miR-196a exerts an oncogenic role in gastric cancer and miR-196a may be a novel biomarker for detecting gastric cancer and for monitoring disease recurrence. (c) 2011 Wiley Periodicals, Inc.