title: Joint effects of Epstein-Barr virus and polymorphisms in interleukin-10 and interferon-γ on breast cancer risk.
abstract: BACKGROUND
  The relationship between Epstein-Barr virus (EBV) and breast cancer (BC) is controversial. Interleukin-10 (IL-10) and interferon-γ (IFN-γ) are believed to play a critical role in the host's responses to EBV infection, and their genetic variations may modify the association of EBV with BC risk.
  
  
  METHODS
  We examined serum levels of EBV viral capsid antigen (VCA) immunoglobulin A (IgA) and nuclear antigen-1 (EBNA-1) IgA along with the polymorphisms of IL-10 rs1800871 and IFN-γ rs2069705 in 354 incident BC cases and 504 age-matched controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using multivariate logistic regression.
  
  
  RESULTS
  VCA IgA and EBNA-1 IgA levels were positively associated with BC risk. IL-10 rs1800871 (TC/CC) was associated with a reduced BC risk (OR, 0.74 [95% CI, 0.55-1.00]) but had no interaction with EBV infection on BC risk. IFN-γ rs2069705 was not directly associated with BC risk but interacted with EBNA-1 IgA on BC risk. Among women with the CC genotype, EBNA-1 IgA seropositivity significantly increased the risk of BC compared to EBNA-1 IgA seronegativity (OR, 5.14 [95% CI, 1.76-14.98]).
  
  
  CONCLUSIONS
  These results suggest that EBV may contribute to the risk of BC and that this contribution may be modified by genetic variations in IFN-γ.
authors.affiliation: The School of Public Health, Sun Yat-sen University, Guangzhou, China. renzef@mail.sysu.edu.cn
authors.forename: Jian-Rong
authors.initials: JR
authors.lastname: He
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Chen
authors.forename: Yi
authors.initials: Y
authors.lastname: Su
authors.forename: Yu-Ling
authors.initials: YL
authors.lastname: Cen
authors.forename: Lu-Ying
authors.initials: LY
authors.lastname: Tang
authors.forename: Dan-Dan
authors.initials: DD
authors.lastname: Yu
authors.forename: Wei-Qing
authors.initials: WQ
authors.lastname: Chen
authors.forename: Shen-Ming
authors.initials: SM
authors.lastname: Wang
authors.forename: Er-Wei
authors.initials: EW
authors.lastname: Song
authors.forename: Ze-Fang
authors.initials: ZF
authors.lastname: Ren
mesh_terms: D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood*; D001943:Breast Neoplasms / Q000235:genetics / Q000821:virology*; D016022:Case-Control Studies; D020031:Epstein-Barr Virus Infections / Q000150:complications*; D005260:Female; D004854:Herpesvirus 4, Human / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood*; D007371:Interferon-gamma / Q000235:genetics*; D016753:Interleukin-10 / Q000235:genetics*; D016015:Logistic Models; D008875:Middle Aged; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide
chemical_list: D000914:Antibodies, Viral; D007070:Immunoglobulin A; D016753:Interleukin-10; D007371:Interferon-gamma