title: Role of CYP1A2 1F polymorphism in cancer risk: evidence from a meta-analysis of 46 case-control studies.
abstract: BACKGROUND
  Emerging evidence showed that the common polymorphism (CYP1A2 1F, rs762551 C→A) in the promoter region of the CYP1A2 gene might be associated with susceptibility to cancer in humans. But individually published results were inconclusive. The aim of this meta-analysis is to investigate the association between CYP1A2 1F polymorphism and cancer risk.
  
  
  METHODS
  The Pubmed, Embase, Web of Science and Chinese BioMedical databases were searched for all articles published up to September 1st, 2012. Statistical analyses were performed using the STATA 12.0 software.
  
  
  RESULTS
  Forty-six case-control studies were included with a total of 22,993 cancer cases and 28,420 healthy controls. Meta-analysis results showed that the A allele of CYP1A2 1F polymorphism was associated with a decreased cancer risk (odds ratio [OR]=0.92, 95% confidence interval [CI]: 0.87-0.98, P=0.013). In the subgroup analysis by cancer types, the A allele of CYP1A2 1F polymorphism may increase the risk of breast cancer (OR=1.05, 95% CI: 1.01-1.10, P=0.024), and is also associated with a decreased risk of ovarian cancer (OR=0.70, 95% CI: 0.54-0.89, P=0.004). However, similar results were not found in lung, colorectal, bladder, endometrial, pancreatic and gastric cancers. Further subgroup analysis by ethnicity also showed a significant association between the A allele of CYP1A2 1F polymorphism and a decreased cancer risk among Caucasian populations (OR=0.91, 95% CI: 0.84-0.98, P=0.014); but no significant associations were observed among Asian populations.
  
  
  CONCLUSIONS
  Results from the current meta-analysis indicate that the A allele of CYP1A2 1F polymorphism may be associated with breast and ovarian cancer risk, especially among Caucasian populations.
authors.affiliation: Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, PR China. cmu2h_tz@126.com
authors.forename: Zhong
authors.initials: Z
authors.lastname: Tian
authors.forename: Yi-Ling
authors.initials: YL
authors.lastname: Li
authors.forename: Lin
authors.initials: L
authors.lastname: Zhao
authors.forename: Chen-Liang
authors.initials: CL
authors.lastname: Zhang
mesh_terms: D000483:Alleles; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000208:ethnology / Q000235:genetics*; D016022:Case-Control Studies; D019388:Cytochrome P-450 CYP1A2 / Q000235:genetics* / Q000378:metabolism; D016208:Databases, Factual; D005260:Female; D056726:Genetic Association Studies; D006801:Humans; D016017:Odds Ratio; D010051:Ovarian Neoplasms / Q000208:ethnology / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D012307:Risk Factors; D044465:White People / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; C504573:CYP1A2 protein, human; D019388:Cytochrome P-450 CYP1A2