Reduced miR-203 predicts metastasis and poor survival in esophageal carcinoma

We analyzed data from two non-coding RNA profiling arrays made available by the Gene Expression Omnibus (GEO) and found 17 miRNAs with remarkable differential expression between malignant and normal esophageal tissue. Correlation analysis between expression of these 17 miRNAs and patients' clinicopathological characteristics showed that miR-203 was down-regulated in esophageal carcinoma (EC) tissues and was significantly associated with lymph node metastasis and poor overall survival. Overexpression of miR-203 significantly attenuated cellular proliferation, migration and invasion by EC cells in culture. Additionally, gene expression profiles and bioinformatics analysis revealed KIF5C to be a direct target of miR-203, and KIF5C overexpression partially counteracted the tumor inhibitory effects of miR-203 on EC cells. We also observed that miR-203, reduced KIFC5 protein levels, promoted cytoplasmic accumulation of Axin2, and reversed the invasive phenotype of EC cells. Taken together, these data demonstrate that miR-203 is a tumor suppressor in EC cells and its expression level could potentially be used as a prognostic indicator for EC patient outcomes.