title: HOTAIR overexpression correlated with worse survival in patients with solid tumors.
abstract: BACKGROUND
  HOX transcript antisense intergenic RNA (HOTAIR), a long non-coding RNA transcribed from the antisense strand of the HOXC gene locus, has been reported to be overexpressed in various carcinomas and is thought to be an indicator of poor prognosis.
  
  
  METHODS
  We performed a meta-analysis using qualified relevant literatures to evaluate the prognostic significance of HOTAIR in various solid tumors. Eligible studies were identified from PubMed, EMBASE and ISI Web of Science through multiple search strategies. We extracted and estimated the hazard ratios (HRs) for overall survival (OS), which compared the high and low expression levels of HOTAIR in patients with a variety of solid carcinomas. HRs and 95% confidence intervals (95% CIs) were calculated to pool the effect size.
  
  
  RESULTS
  A total of 2407 patients from 21 studies with various solid carcinomas were included. For OS, higher HOTAIR expression could significantly predict worse outcome with the pooled HR of 2.21 (95 % CI 1.77-2.74, P<0.00001). The subgroup analysis suggested that the elevated levels of HOTAIR appears to be worse OS in Asian population (HR=2.06, 95% CI 1.80-2.37, P<0.00001) and digestive system cancers (HR=2.27, 95% CI 1.93-2.67, P<0.00001) including esophageal squamous cell carcinoma (HR=2.27, 95% CI 1.62-3.18, P<0.00001) and colorectal cancer (HR=4.65, 95 % CI 2.39-9.05, P<0.00001).
  
  
  CONCLUSIONS
  The present meta-analysis revealed that the high level of HOTAIR is associated with an adverse OS in numerous solid cancers, suggesting that HOTAIR may be a predictor of poor prognosis for the development of solid tumors.
authors.affiliation: Department of Breast and Thyroid Surgery, Zhangjiagang Hospital Affiliated to Soochow University, Zhangjiagang Hospital, Jiangsu Province, China - lancetyang@126.com.
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Miao
authors.forename: Jinhua
authors.initials: J
authors.lastname: Ding
authors.forename: Bijuan
authors.initials: B
authors.lastname: Chen
authors.forename: Yinlong
authors.initials: Y
authors.lastname: Yang
authors.forename: Yizuo
authors.initials: Y
authors.lastname: Chen
mesh_terms: D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D009369:Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000401:mortality*; D062085:RNA, Long Noncoding / Q000096:biosynthesis*; D015996:Survival Rate
chemical_list: C561566:HOTAIR long untranslated RNA, human; D062085:RNA, Long Noncoding