title: Association of IL-6 Promoter and Receptor Polymorphisms with Multiple Myeloma Risk: A Systematic Review and Meta-Analysis.
abstract: BACKGROUND
  A number of studies show that the pleiotropic cytokine interleukin-6 (IL-6) plays an important role in the pathogenesis of multiple myeloma (MM). However, whether MM risk is associated with IL-6 genetic variability remains uncertain.
  
  
  OBJECTIVE
  The aim of our study was to evaluate the association between two different IL-6 polymorphisms (located in the IL-6 promoter and receptor, respectively) and the risk of developing MM using a meta-analytic approach.
  
  
  METHODS
  A systematic search for studies on the association of IL-6/IL-6R single-nucleotide polymorphisms with susceptibility to MM was conducted in PubMed, Cochrane Library, Embase, CNKI (Chinese) and Wanfang (Chinese) Digital Dissertations Databases from inception through November 2014. A meta-analysis was performed and results were presented as odds ratios (ORs) with 95% confidence intervals (CIs).
  
  
  RESULTS
  A total of eight case-control studies on the IL-6 promoter polymorphism and three studies on the IL-6 receptor (IL-6R) polymorphism were included. No significant association was found between the IL-6 promoter rs1800795 (G>C) polymorphism and MM susceptibility. A significantly increased risk of MM was observed with the IL-6R rs8192284 (A>C) polymorphism. In subgroup analyses, grouped by ethnicity, region, quality of studies, and Hardy-Weinberg equilibrium of control group, similar results were found.
  
  
  CONCLUSIONS
  Unlike the IL-6 promoter rs1800795 (G>C) polymorphism, the IL-6R rs8192284 (A>C) polymorphism may be associated with MM risk. However, large-scale studies are needed to validate our findings since they are based on a relatively small number of studies.
authors.affiliation: Cancer Center, First Hospital of Jilin University , Changchun, China .
authors.forename: Yuying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Cancer Center, First Hospital of Jilin University , Changchun, China .
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Du
authors.affiliation: Cancer Center, First Hospital of Jilin University , Changchun, China .
authors.forename: Xu
authors.initials: X
authors.lastname: Wang
authors.affiliation: Cancer Center, First Hospital of Jilin University , Changchun, China .
authors.forename: Guanjun
authors.initials: G
authors.lastname: Wang
authors.affiliation: Cancer Center, First Hospital of Jilin University , Changchun, China .
authors.forename: Wei
authors.initials: W
authors.lastname: Li
mesh_terms: D020022:Genetic Predisposition to Disease; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D009101:Multiple Myeloma / Q000235:genetics*; D009363:Neoplasm Proteins / Q000235:genetics*; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D019947:Receptors, Interleukin-6 / Q000235:genetics
chemical_list: C508600:IL6 protein, human; C508603:IL6R protein, human; D015850:Interleukin-6; D009363:Neoplasm Proteins; D019947:Receptors, Interleukin-6
keywords: IL-6 promoter; IL-6 receptor; SNPs; meta-analysis; multiple myeloma