title: Prognostic value of miR-21 in various cancers: an updating meta-analysis.
abstract: BACKGROUND
  Recently, more and more studies investigated the value of microRNA (miRNA) as a diagnostic or prognostic biomarker in various cancers. MiR-21 was found dysregulated in almost all types of cancers. While the prognostic role of miR-21 in many cancers has been studied, the results were not consistent.
  
  
  METHODS
  We performed a meta-analysis to investigate the correlation between miR-21 and survival of general cancers by calculating pooled hazard ratios (HR) and 95% confidence intervals (CI).
  
  
  RESULTS
  The pooled results of 63 published studies showed that elevated miR-21 was a predictor for poor survival of general carcinomas, with pooled HR of 1.91 (95%CI: 1.66-2.19) for OS, 1.42 (95% CI: 1.16-1.74) for DFS and 2.2 (95% CI: 1.64-2.96) for RFS/CSS. MiR-21 was also a prognostic biomarker in the patients who received adjuvant therapy, with pooled HR of 2.4 (95%CI: 1.18-4.9) for OS.
  
  
  CONCLUSIONS
  Our results showed that miR-21 could act as a significant biomarker in the prognosis of various cancers. Further studies are warranted before the application of the useful biomarker in the clinical.
authors.affiliation: Department of Oncology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Human Functional Genomics of Jiangsu Province, Clinical Diabetes Centre of Jiangsu Province, Nanjing Medical University, Nanjing, China.
authors.forename: Xiaping
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Oncology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Zebo
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Oncology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Oncology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Department of Oncology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China; Cancer Center of Nanjing Medical University, Nanjing, China.
authors.forename: Yongqian
authors.initials: Y
authors.lastname: Shu
authors.affiliation: Department of Oncology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China; Cancer Center of Nanjing Medical University, Nanjing, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Liu
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D016014:Linear Models; D035683:MicroRNAs / Q000378:metabolism* / Q000502:physiology; D009369:Neoplasms / Q000235:genetics*; D011237:Predictive Value of Tests; D011379:Prognosis; D017594:Publication Bias; D016019:Survival Analysis
chemical_list: D014408:Biomarkers, Tumor; C524940:MIRN21 microRNA, human; D035683:MicroRNAs