title: Relationship between apurinic endonuclease 1 Asp148Glu polymorphism and gastrointestinal cancer risk: An updated meta-analysis.
abstract: OBJECTIVE
  To evaluate the relationship between apurinic endonuclease 1 (APE1) Asp148Glu polymorphism and the susceptibility to gastrointestinal (GI) cancers.
  
  
  METHODS
  We searched PubMed, ISI Web of Knowledge, and Chinese National Knowledge Infrastructure (CNKI) databases updated on July 15, 2014 for relevant studies. Only case-control studies comparing APE1 Asp148Glu polymorphism and GI cancer risk were included. We excluded studies reporting only standardized incidence ratios without control groups and those without detailed genotyping data. Meta-analysis was performed on 17 studies involving 4856 cancer patients and 6136 cancer-free controls. Review Manager version 5.1 was used to perform the meta-analysis. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated under the allele contrast, homozygous, heterozygous, dominant and recessive genetic models. We also conducted subgroup analyses stratified by ethnicity and cancer type. Publication bias was evaluated using Begg's test.
  
  
  RESULTS
  The meta-analysis showed a significant association between APE1 Asp148Glu polymorphism and GI cancer risk in three genetic models in the overall population (G vs T: OR = 1.18; 95%CI: 1.05-1.32; TG vs TT: OR = 1.28; 95%CI: 1.08-1.52; TG + GG vs TT: OR = 1.32; 95%CI: 1.10-1.57). Stratified analysis by ethnicity revealed a statistically increased GI cancer risk in Asians (G vs T: OR = 1.27; 95%CI: 1.07-1.51; GG vs TT: OR = 1.58; 95%CI: 1.05-2.38; TG vs TT: OR = 1.30; 95%CI, 1.01- 1.67; and TG + GG vs TT: OR = 1.38; 95%CI: 1.07-1.78), but not in Caucasians. Further subgroup analysis by cancer type indicated that APE1 Asp148Glu polymorphism may contribute to gastric cancer risk. However, Asp148Glu has no significant association with colorectal or esophageal cancer risk in any genetic model.
  
  
  CONCLUSIONS
  This meta-analysis suggests that the APE1 Asp148Glu polymorphism G allele is associated with an increased GI cancer risk, especially in gastric cancer.
authors.affiliation: Zhi-Jun Dai, Hua-Feng Kang, Yang Zhao, Di Liu, Meng Wang, Peng-Tao Yang, Xi-Jing Wang, Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Zhi-Jun
authors.initials: ZJ
authors.lastname: Dai
authors.affiliation: Zhi-Jun Dai, Hua-Feng Kang, Yang Zhao, Di Liu, Meng Wang, Peng-Tao Yang, Xi-Jing Wang, Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Yong-Ping
authors.initials: YP
authors.lastname: Shao
authors.affiliation: Zhi-Jun Dai, Hua-Feng Kang, Yang Zhao, Di Liu, Meng Wang, Peng-Tao Yang, Xi-Jing Wang, Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Hua-Feng
authors.initials: HF
authors.lastname: Kang
authors.affiliation: Zhi-Jun Dai, Hua-Feng Kang, Yang Zhao, Di Liu, Meng Wang, Peng-Tao Yang, Xi-Jing Wang, Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Tang
authors.affiliation: Zhi-Jun Dai, Hua-Feng Kang, Yang Zhao, Di Liu, Meng Wang, Peng-Tao Yang, Xi-Jing Wang, Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Xu
authors.affiliation: Zhi-Jun Dai, Hua-Feng Kang, Yang Zhao, Di Liu, Meng Wang, Peng-Tao Yang, Xi-Jing Wang, Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Zhi-Jun Dai, Hua-Feng Kang, Yang Zhao, Di Liu, Meng Wang, Peng-Tao Yang, Xi-Jing Wang, Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Di
authors.initials: D
authors.lastname: Liu
authors.affiliation: Zhi-Jun Dai, Hua-Feng Kang, Yang Zhao, Di Liu, Meng Wang, Peng-Tao Yang, Xi-Jing Wang, Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Wang
authors.affiliation: Zhi-Jun Dai, Hua-Feng Kang, Yang Zhao, Di Liu, Meng Wang, Peng-Tao Yang, Xi-Jing Wang, Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Peng-Tao
authors.initials: PT
authors.lastname: Yang
authors.affiliation: Zhi-Jun Dai, Hua-Feng Kang, Yang Zhao, Di Liu, Meng Wang, Peng-Tao Yang, Xi-Jing Wang, Department of Oncology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Xi-Jing
authors.initials: XJ
authors.lastname: Wang
mesh_terms: D044466:Asian People / Q000235:genetics; D016009:Chi-Square Distribution; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000235:genetics*; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis / Q000201:enzymology / Q000208:ethnology / Q000235:genetics*; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D016014:Linear Models; D016017:Odds Ratio; D010641:Phenotype; D011110:Polymorphism, Genetic; D018570:Risk Assessment; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000201:enzymology / Q000235:genetics
chemical_list: C085108:APEX1 protein, human; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase
keywords: Apurinic endonuclease 1; Cancer risk; Gastrointestinal cancers; Meta-analysis; Single nucleotide polymorphism