title: Prognostic Value of High CXCR4 Expression in Renal Cell Carcinoma: A System Review and Meta-Analysis.
abstract: BACKGROUND
  Recent studies have shown that CXC chemokine receptor 4 (CXCR4) is involved in the progression and metastasis of renal cell carcinoma (RCC). However, the prognostic value of CXCR4 expression in RCC remains controversial. The aim of our meta-analysis is to evaluate the prognostic value of high CXCR4 expression in RCC.
  
  
  METHODS
  Relevant studies focused on the relationship between high CXCR4 expression and the outcome of RCC were searched in PubMed and EMBASE/Cochrane Library database. Hazard ratios (HRs) of overall survival (OS) and progression-free survival (PFS) were our evaluation index. The individual and pooled HRs with 95% confidence intervals (CIs) were analyzed.
  
  
  RESULTS
  A total of 1068 patients from 7 studies were included in our meta-analysis. The results suggested that high CXCR4 expression predicted a poor OS (random effect model (REM) HR = 2.77, 95% CI = 1.80-4.27) and PFS (REM HR = 4.83, 95% CI = 2.30-10.15) for RCC patients.
  
  
  CONCLUSIONS
  The results of meta-analysis indicated that high CXCR4 expression was correlated with worse OS and PFS for patients with RCC. However, some larger samples and well-matched studies should be designed to estimate the potential prognosis of RCC patients.
authors.affiliation: Department of Urology, First Affiliated Hospital of Medical School, Xi'an Jiaotong University, Xi'an, Shaanxi, China.
authors.forename: Yuefeng
authors.initials: Y
authors.lastname: Du
authors.affiliation: Department of Urology, First Affiliated Hospital of Medical School, Xi'an Jiaotong University, Xi'an, Shaanxi, China.
authors.forename: Qingzhi
authors.initials: Q
authors.lastname: Long
authors.affiliation: Department of Urology, First Affiliated Hospital of Medical School, Xi'an Jiaotong University, Xi'an, Shaanxi, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Guan
authors.affiliation: Department of Urology, First Affiliated Hospital of Medical School, Xi'an Jiaotong University, Xi'an, Shaanxi, China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Mu
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D002292:Carcinoma, Renal Cell / Q000378:metabolism* / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D019718:Receptors, CXCR4 / Q000235:genetics / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; C527276:CXCR4 protein, human; D019718:Receptors, CXCR4