title: No association of single nucleotide polymorphisms involved in GHRL and GHSR with cancer risk: a meta-analysis.
abstract: BACKGROUND
  Ghrelin was associated with several of cancers. The conflict results of SNPs with GHRL and GHSR gene were demonstrated in different studies. Thus, this meta-analysis is to evaluate the associations.
  
  
  METHODS
  Systematic literature search was done on PubMed database up to October 2013. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association by a fixed-effect model and a random-effect model.
  
  
  RESULTS
  A total of 7 studies, which included 3 studies for breast cancer, 2 for colorectal cancer, 1 for hepatocellular carcinoma, 1 for esophageal cancer and 1 for Non-Hodgkin lymphoma. When analyzed all the GHRL SNPs with all kinds of cancers, there was significantly difference with cancer patients compared with controls (Recessive model: OR 0.938, 95% CI 0.890-0.989, p=0.017), while no significant difference was existed in the additive model (OR 0.9903, 95% CI 0.957-1.024, p=0.558) and dominant model (OR 1.014, 95% CI 0.970-1.061, p=0.536). When analyzed all the GHSR SNPs with all kinds of cancers, no significant difference was observed.
  
  
  CONCLUSIONS
  Our results suggest that the SNP with GHRL and GHSR might be weaker association with cancer risk, especially with breast cancer risk.
authors.affiliation: Department of Oncology, Wendeng Central Hospital of Weihai City, Weihai, Shandong, China.
authors.forename: Shengjie
authors.initials: S
authors.lastname: Zhu
authors.affiliation: Department of Radiology, Wendeng Central Hospital of Weihai City, Weihai, Shandong, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Shao
authors.affiliation: Department of Hepatobiliary Surgery, General Hospital of People's Liboration Army, Beijing, China.
authors.forename: Yaoyao
authors.initials: Y
authors.lastname: Hao
authors.affiliation: Department of Oncology, Wendeng Central Hospital of Weihai City, Weihai, Shandong, China.
authors.forename: Zongxian
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Oncology, Wendeng Central Hospital of Weihai City, Weihai, Shandong, China.
authors.forename: Houqiang
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Oncology, Wendeng Central Hospital of Weihai City, Weihai, Shandong, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Oncology, Wendeng Central Hospital of Weihai City, Weihai, Shandong, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Oncology, Wendeng Central Hospital of Weihai City, Weihai, Shandong, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D020022:Genetic Predisposition to Disease; D054439:Ghrelin / Q000235:genetics*; D006801:Humans; D008875:Middle Aged; D009369:Neoplasms / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D054440:Receptors, Ghrelin / Q000235:genetics*; D012306:Risk
chemical_list: C515349:GHRL protein, human; D054439:Ghrelin; D054440:Receptors, Ghrelin
keywords: GHRL; GHSR; cancer; meta-analysis