title: Association between COX-2 -1195G>A polymorphism and gastrointestinal cancer risk: A meta-analysis.
abstract: OBJECTIVE
  To perform a meta-analysis to investigate the association between cyclooxygenase-2 (COX-2) -1195G>A gene polymorphism and gastrointestinal cancers.
  
  
  METHODS
  Publications related to the COX-2 -1195G>A gene polymorphism and gastrointestinal cancers published before July 2016 were retrieved from PubMed, EMBASE, Web of Science, China Biological Medicine Database, China National Knowledge Infrastructure, and CQVIP Database. Meta-analysis was performed using Stata11.0 software. The strength of the association was evaluated by calculating the combined odds ratios (ORs) and the corresponding 95%CIs. The retrieved publications were excluded or included one by one for sensitivity analysis. In addition, the funnel plot, Begg's rank correlation test, and Egger's linear regression method were applied to analyse whether the included publications had publication bias.
  
  
  RESULTS
  A total of 24 publications related to the COX-2 -1195G>A gene polymorphism were included, including 28 studies involving 11043 cases and 18008 controls. The meta-analysis results showed that the COX-2 -1195G>A gene polymorphism significantly correlated with an increased risk of gastrointestinal cancers, particularly gastric cancer (AvsG: OR = 1.35; AA/AGvsGG: OR = 1.54; AAvsGG/AG: OR = 1.43; AAvsGG: OR = 1.80; AGvsGG: OR = 1.35). Compared to the Caucasian population in America and Europe, the COX-2 -1195G>A gene polymorphism in the Asian population (AvsG: OR = 1.30; AA/AGvsGG: OR = 1.50; AAvsGG/AG: OR = 1.35; AAvsGG: OR = 1.71; AGvsGG: OR = 1.37) significantly increased gastrointestinal cancer risk. The sensitivity analysis (P< 0.05) and the false positive report probability (P< 0.2) confirmed the reliability of the results.
  
  
  CONCLUSIONS
  The results showed that the COX-2 -1195G>A gene polymorphism might be a potential risk factor for gastrointestinal cancers. Further validation by a large homogeneous study is warranted.
authors.affiliation: Xiao-Wei Zhang, Jun Li, Yu-Xiang Chen, Department of Gastrointestinal and Vascular Surgery, Deyang People's Hospital, Deyang 618099, Sichuan Province, China.
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Zhang
authors.affiliation: Xiao-Wei Zhang, Jun Li, Yu-Xiang Chen, Department of Gastrointestinal and Vascular Surgery, Deyang People's Hospital, Deyang 618099, Sichuan Province, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: Xiao-Wei Zhang, Jun Li, Yu-Xiang Chen, Department of Gastrointestinal and Vascular Surgery, Deyang People's Hospital, Deyang 618099, Sichuan Province, China.
authors.forename: Yu-Xing
authors.initials: YX
authors.lastname: Jiang
authors.affiliation: Xiao-Wei Zhang, Jun Li, Yu-Xiang Chen, Department of Gastrointestinal and Vascular Surgery, Deyang People's Hospital, Deyang 618099, Sichuan Province, China.
authors.forename: Yu-Xiang
authors.initials: YX
authors.lastname: Chen
mesh_terms: D044466:Asian People; D051546:Cyclooxygenase 2 / Q000235:genetics*; D005189:False Positive Reactions; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis* / Q000208:ethnology / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D018401:Sample Size
chemical_list: D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human
keywords: -1195G>A; COX-2; Gastrointestinal cancer; Meta-analysis; Polymorphism