title: Polymorphisms of progesterone receptor and ovarian cancer risk: a systemic review and meta-analysis.
abstract: OBJECTIVE
  Growing bodies of studies have investigated the associations between three progesterone receptor (PGR) polymorphisms, +331G/A, Alu insertion and Val660Leu, and susceptibility to ovarian cancer, but the results remain controversial and inconclusive. Thus, we conducted a meta-analysis to derive a more precise estimation of the associations.
  
  
  METHODS
  A total of 21 case-control studies from 16 publications that included analyses of Alu insertion (981 cases, 2136 controls), Val660Leu (2205 cases, 3222 controls) and +331G/A (2842 cases, 4305 controls) polymorphisms were identified.
  
  
  RESULTS
  Significantly increased risks of ovarian cancer were found for Alu insertion (T2 T2  + T1 T2 vs T1 T1 ; odds ratio [OR], 1.504; 95% confidence interval [CI], 1.206-2.203) and Val660Leu (TT vs GT; OR, 1.524; 95% CI, 1.013-2.293). No significant association was found between +331G/A polymorphism and ovarian cancer.
  
  
  CONCLUSIONS
  This meta-analysis suggests that the two polymorphisms of PGR, Alu insertion and Val660Leu, may contribute to ovarian cancer susceptibility as low-penetrance risk factors.
authors.affiliation: Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Liao
authors.forename: Dong
authors.initials: D
authors.lastname: Ding
authors.forename: Chaoyang
authors.initials: C
authors.lastname: Sun
authors.forename: Danhui
authors.initials: D
authors.lastname: Weng
authors.forename: Li
authors.initials: L
authors.lastname: Meng
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.forename: Ding
authors.initials: D
authors.lastname: Ma
mesh_terms: D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D010051:Ovarian Neoplasms / Q000235:genetics*; D019683:Penetrance; D020641:Polymorphism, Single Nucleotide; D011980:Receptors, Progesterone / Q000235:genetics*; D012307:Risk Factors
chemical_list: D011980:Receptors, Progesterone
keywords: meta-analysis; ovarian cancer; ovarian cancer risk; polymorphism; progesterone receptor