title: Association between PTEN IVS4 polymorphism and cancer risk: a meta-analysis.
abstract: BACKGROUND
  PTEN, a candidate tumor suppressor gene, has been identified within chromosome 10q23 and plays an important role in tumorigenesis. The association between the IVS4 insertion/deletion (I/D) polymorphism of PTEN and cancer risk in several populations has been studied, but results are conflicting. The aim of the present study was to investigate association of PTEN IVS4 polymorphism with cancer risk by conducting a meta-analysis.
  
  
  METHODS
  A literature search was conducted through PubMed, Chinese National Knowledge Infrastructure (CNKI) and WanFang databases (up to October 18, 2013). Six eligible studies with 2,179 cases and 3,132 controls were enrolled in the meta-analysis. The pooled odds ratio (OR) and 95% confidence intervals (CI) were used to assess the strength of association.
  
  
  RESULTS
  Our results indicated that the~polymorphism conferred a significantly decreased risk of overall cancer (dominant model: OR=0.87, 95% CI 0.77-0.99; recessive model: OR=0.83, 95% CI: 0.72-0.96; II vs. DD model: OR=0.79, 95% CI: 0.67-0.94; I vs. D model: OR=0.89, 95% CI: 0.82-0.97). Subgroup analysis by cancer type and ethnicity furtherly showed that PTEN gene IVS4 polymorphism was associated with decreased risk of digestive cancers (recessive model: OR=0.77, 95% CI: 0.64-0.92; II vs. DD model: OR=0.72, 95% CI: 0.58-0.91; I vs. D model: OR=0.84, 95% CI: 0.76-0.94), this strong association with reduced risk of cancer was also found in Asian population (recessive model: OR=0.83, 95% CI: 0.71-0.98; II vs. DD model: OR=0.79, 95% CI: 0.65-0.96; I vs. D model: OR=0.89, 95% CI: 0.81-0.98).
  
  
  CONCLUSIONS
  In conclusion, our meta-analysis suggested that PTEN IVS4 polymorphism might play a protective role in the development of cancer, further independent confirmation of associations observed in PTEN IVS4 polymorphism by more studies was necessary.
authors.affiliation: Department of Microbiology and Immunology, Southeast University Medical School, Nanjing, Jiangsu, China.
authors.forename: Xueren
authors.initials: X
authors.lastname: Gao
authors.affiliation: Department of Obstetrics and Gynecology, Xi'an, Shanxi, China.
authors.forename: Haixia
authors.initials: H
authors.lastname: Duan
authors.affiliation: Department of Forensic Medicine, Xuzhou Medical College, Xuzhou, Jiangsu, China.
authors.forename: Zhansheng
authors.initials: Z
authors.lastname: Zhu
mesh_terms: D016022:Case-Control Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D009369:Neoplasms / Q000201:enzymology* / Q000235:genetics*; D051059:PTEN Phosphohydrolase / Q000235:genetics* / Q000378:metabolism; D011110:Polymorphism, Genetic
chemical_list: D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human
keywords: PTEN; cancer risk; meta-analysis; polymorphism