High Expression of Mir-21 in Tissue Correlated With the Poor Survival of Patients With Esophageal Cancer: A Pilot Study Using the Meta-analysis - High Expression of Mir-21 in Tissue Correlated With the Poor Survival of Patients With Esophageal Cancer: A Pilot Study Using the Meta-analysis - Open Access Pub

Objective: MicroRNAs are involved in the onset, progression and dissemination of esophageal cancer, and they may be useful as prognostic biomarkers. This study aims to evaluate the relation of miR-21 expression and the prognosis of esophageal cancer patients. Methods: In this study, a meta-analysis is performed by searching PubMed, Science Direct databases, and Cochrane Library. Data are extracted from studies evaluating survival of esophageal cancer patients with either high or low miR-21 expression. Pooled hazard ratios (HRs) and 95% confidence intervals (CI) are calculated. Results: A total of 579 cases of esophageal cancer from five studies are involved for this global meta-analysis. The HR of survival of patients with high miR-21 expression is 1.47 (95% CI: 1.12–1.91; p<0.01) as compared with those with low expression. Conclusions: miR-21 may be a predictor for survival of esophageal cancer patients. MicroRNAs are involved in the onset, progression and dissemination of esophageal cancer, and they may be useful as prognostic biomarkers. This study aims to evaluate the relation of miR-21 expression and the prognosis of esophageal cancer patients. In this study, a meta-analysis is performed by searching PubMed, Science Direct databases, and Cochrane Library. Data are extracted from studies evaluating survival of esophageal cancer patients with either high or low miR-21 expression. Pooled hazard ratios (HRs) and 95% confidence intervals (CI) are calculated. A total of 579 cases of esophageal cancer from five studies are involved for this global meta-analysis. The HR of survival of patients with high miR-21 expression is 1.47 (95% CI: 1.12–1.91; p<0.01) as compared with those with low expression. miR-21 may be a predictor for survival of esophageal cancer patients. DOI10.14302/issn.2474-3585.jpmc-15-757 Esophageal cancer (EC) is the eighth most common cancer in the world, affecting approximately 500,000 individuals worldwide each year 1, 2. EC consists of two predominant histological subtypes, squamous cell carcinoma and adenocarcinoma 3. Esophageal squamous cell carcinoma accounts for more than 90% of esophageal carcinomas in Asian countries, while esophageal adenocarcinoma affects white populations predominantly. The biology of EC was of aggressive local invasion, early metastasis, and resistance to chemotherapy. Despite improvements in detection, surgical resection, and adjuvant therapy, the prognosis for long-term survival of EC remains poor 4. MicroRNAs (miRNAs) are small non-protein coding RNAs that function as negative gene regulators at the