Association of miR-21 with esophageal cancer prognosis: a meta-analysis

The present study aimed to explore the relationship between miRNA expression and survival in patients with esophageal cancer (EC) using meta-analysis. We searched PubMed, EMBASE, CNKI, Wanfang, and ISI Web of Science databases without time restrictions, and extracted relevant data, such as the name of first author, publication year, age, gender, number of case, etc. from the studies included. We calculated the pooled hazard ratios (HRs) using the RevMan 5.2 software. A total of five studies involving 504 subjects were included in the meta-analysis, with the purpose of analyzing the association of miRNA-21 expression with EC prognosis. The pooled HR of elevated versus decreased miR-21 expression in EC was 1.87 [95% confidence interval (CI): 1.37-2.55, P < 0.001], with elevated miR-21 expression being associated with poorer prognosis for patients with EC. Our results support a prognostic role for miR-21 in EC.