title: The expression of miR-21 and miR-375 predict prognosis of esophageal cancer.
abstract: BACKGROUND
  MicroRNA is a class of small, well-conserved, non-coding RNAs, and could play a potential role as diagnostic and prognostic biomarkers of esophageal cancers. We aimed to review comprehensively the evidence of microRNA as prognostic biomarkers in esophageal cancers.
  
  
  METHODS
  Studies were identified by searching PubMed, Embase and Web of Science until November 2013. Descriptive characteristics of studies were described and an additional meta-analysis for specific microRNAs which were studied most frequently was performed. Pooled hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) were calculated. Fixed model or random model method was chosen depending on the heterogeneity among the studies.
  
  
  RESULTS
  Twenty-two studies including a total of 1946 participants were enrolled after a strict filtering and qualifying process. Among 33 prognostic microRNAs identified for esophageal cancer, miR-21 and miR-375 appeared more frequently. The median study size was 70.5 patients (29-249 patients) and the median HR was 3.305 (IQR=1.615-7.31). For the studies evaluating miR-21's association with overall survival (OS), the pooled HR suggested that high level of miR-21 has a negative impact on OS (HR=1.52[1.17-1.98], P=0.001). As for miR-375, the pooled HR for OS (high/low) was 0.53 (95% CI: 0.39-0.73, P<0.001), indicated that low level of miR-375 has a negative impact on OS. These results indicated that microRNAs show promising associations with prognosis in esophageal cancer. Up-regulation of miR-21 and down-regulation of miR-375 can predict unfavourable prognosis in esophageal cancer.
authors.affiliation: Sixth Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong Province, China; School of Medicine and Life Sciences, University of Jinan - Shandong Academy of Medical Sciences, Jinan, Shandong Province, China.
authors.forename: Chengrui
authors.initials: C
authors.lastname: Fu
authors.affiliation: Sixth Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong Province, China; Department of Radiation Oncology, Cancer Hospital, Tianjin Medical University, Tianjin Province, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Dong
authors.affiliation: Sixth Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong Province, China; Department of Radiation Oncology, Cancer Hospital, Tianjin Medical University, Tianjin Province, China.
authors.forename: Zhiwu
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Sixth Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong Province, China.
authors.forename: Hongsheng
authors.initials: H
authors.lastname: Li
authors.affiliation: Sixth Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong Province, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Qin
authors.affiliation: Sixth Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong Province, China. Electronic address: baoshli@yahoo.com.
authors.forename: Baosheng
authors.initials: B
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015536:Down-Regulation; D004938:Esophageal Neoplasms / Q000175:diagnosis* / Q000235:genetics*; D004947:Esophagus / Q000378:metabolism / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D011379:Prognosis; D016019:Survival Analysis; D015854:Up-Regulation
chemical_list: C524940:MIRN21 microRNA, human; C540933:MIRN375 microRNA, human; D035683:MicroRNAs
keywords: Esophageal cancer; MicroRNA; Prognosis