MicroRNA profiles to predict postoperative prognosis in patients with small cell carcinoma of the esophagus

Background/Aim: Small cell carcinoma of the esophagus (SCCE) is a rare but very aggressive disease with poor prognosis. The aim of the present study was to identify a molecular signature to predict postoperative outcomes in patients with SCCE. Materials and Methods: Expression of microRNA was detected in surgically-removed SCCE tumors using microarrays. A SCCE cell line (TYUC-1) was established to investigate the biological role of differentially expressed microRNAs. Results: Hierarchical clustering of microRNA expression revealed two discrete clusters that were identical to the cases with rapid tumor relapse (n=3; median survival, 5.1 months) and the cases with long-term survival (n=3; median observation, 144.7 months), respectively. Eight microRNAs (miR-4323, miR-625, miR-3619-3p, miR-4419b, miR-1249, miR-4648, miR-4664-3p and miR-1203) showed significant correlation with tumor relapse (p<0.01). Migration of TYUC-1 was significantly inhibited by down-regulation of miR-625. Conclusion: The expression profiles of microRNAs in tumors may represent a novel predictor for postoperative outcomes in patients with SCCE.