Serum miR-200c expression level as a prognostic biomarker for gastric cancer

The aim of the present study was to analyze the serum expression level of microRNA-200c (miR-200c) in gastric cancer (GC) patients and to determine the relationship between this expression and clinicopathological features and survival. Serum samples were obtained from 98 patients with GC between February 2008 and January 2013. Quantitative RT-PCR was used to assess miR-200c expression levels in serum samples. Survival curves were plotted using the Kaplan-Meier method, and differences between survival curves were compared by the log rank test. The Cox proportional hazard regression model was used to analyze the risk factors for GC. Relative serum miR-200c level was found to be significantly higher in patients with GC than healthy controls. Mean serum miR-200c level was 97.43 +/- 26.16 in the GC group and 20.79 +/- 14.61 in the control group (P < 0.0001). Serum miR-200c level was also significantly associated with tumor grade (P = 0.01) and TNM stage (P = 0.009). Kaplan-Meier survival curves demonstrated that the overall survival rate was significantly lower in the patients with high serum miR-200c level than in those with low levels (27.9 vs 55.9%, P = 0.007). In addition, multivariate analysis confirmed that the hazard risk (HR) of death was significantly higher in patients with high serum miR-200c expression levels compared with low expression levels (HR = 4.01, 95% CI = 2.67-10.02, P = 0.006). The relative expression of serum miR-200c in GC patients was significantly higher compared to healthy controls, and it may prove to be useful in assessing the prognosis of GC.