Downregulation of miR-519a Predicts Poor Prognosis and Contributes to Tumor Progression in Gastric Cancer.

INTRODUCTION

MicroRNAs (miRNAs) have been demonstrated to be involved in the pathogenesis of various human cancers. However, the role of microRNA-519a (miR-519a) in gastric cancer (GC) remains unclear. This study aimed to investigate the clinical value and biological function of miR-519a in GC.

METHODS

The expression of miR-519a in GC tissues and cell lines was estimated by quantitative real-time polymerase chain reaction. Survival analysis for GC patients was performed using the Kaplan-Meier method. Cox regression analysis was used to confirm the prognostic value of miR-519a. The biological function and potential targets of miR-519a in GC progression were assessed using cell experiments.

RESULTS

In this study, we found that miR-519a was an important tumor suppressor with downregulated expression in GC tissues and cells compared with that in normal controls (all p < 0.05). MiR-519a expression was inversely correlated with differentiation, lymph node metastasis, and the TNM stage of patients. Decreased miR-519a expression was associated with the poor overall survival of GC patients (log-rank p = 0.002) and served as an independent prognostic biomarker for the patients. The in vitro analyses indicated that miR-519a overexpression in GC cells resulted in inhibited cell proliferation, migration, and invasion, and IGFBP1 was determined to be a direct target of miR-519a.

CONCLUSION

All the data in the present study revealed that the downregulated expression of miR-519a predicts the poor prognosis of GC and is involved in the regulation of GC progression. We consider that miR-519a may be a candidate therapeutic target for GC treatment.