title: Profiles of gene polymorphisms in cytokines and Toll-like receptors with higher risk for gastric cancer.
abstract: BACKGROUND
  Chronic inflammation and gastric carcinogenesis show a close association, so gene polymorphisms that modify the intensity of the inflammatory response may contribute to variations in gastric cancer risk.
  
  
  OBJECTIVE
  The purpose of this study was to investigate the combined effect of the pro- and anti-inflammatory cytokines and toll-like receptors polymorphisms on the chronic gastritis and gastric cancer risk in a Brazilian population sample.
  
  
  METHODS
  We evaluated 669 DNA samples (200 of gastric cancer [GC], 229 of chronic gastritis [CG], and 240 of healthy individuals [C]). Ten polymorphisms were genotyped: IL-1RN and TLR2 -196 to -174 del using the allele-specific PCR method and TNF-A (rs1800629; rs1799724), TNF-B (rs909253), IL-8 (rs4073; rs2227532), IL-10 (rs1800872) and TLR4 (rs4986790; rs4986791) using PCR-RFLP.
  
  
  RESULTS
  Polymorphisms TNF-A-308G/A, IL-8-251A/T, TNF-B + 252A/G and TLR4 + 1196C/T were not associated with risk of any gastric lesion. However, an association with increased risk for GC was observed for polymorphisms IL-1RNL/2 (p < 0.001), TNF-A-857C/T (p = 0.022), IL-8-845T/C (p < 0.001), IL-10-592C/A (p < 0.001), TLR2ins/del (p < 0.001), and TLR4 + 896A/G (p = 0.033). In CG, an association was observed only with polymorphisms IL-1RNL/2 and IL-10-592A/C (p < 0.001 for both). A combined analysis of these six polymorphisms associated with GC revealed a profile with two to four combined genotypes which confer a higher risk of gastric carcinogenesis, with an OR increased 2.95-fold to 50.4-fold, highlighting the combinations IL-1RN2/TNF-A-857T/IL-8-845C, IL-1RN2/IL-8-845C/TLR2del, IL-1RN2/IL-10-592A/TLR4 + 896G, IL-10-592A/TLR2del/TLR4 + 896G, and IL-1RN2/TNFA-857T/IL8-845C/TLR2del.
  
  
  CONCLUSIONS
  Our findings evidenced that the combined effect of polymorphisms in genes involved in the inflammatory process may potentiate the risk of gastric cancer, thus emphasizing the importance of evaluating multiple polymorphisms together.
authors.affiliation: Department of Biology, São Paulo State University (UNESP), Rua Cristovão Colombo, 2265, São José do Rio Preto, 15054-000 SP, Brazil. kjuliana21@yahoo.com.br
authors.forename: Juliana Garcia
authors.initials: JG
authors.lastname: de Oliveira
authors.forename: Ana Flávia Teixeira
authors.initials: AF
authors.lastname: Rossi
authors.forename: Daniela Manchini
authors.initials: DM
authors.lastname: Nizato
authors.forename: Kenji
authors.initials: K
authors.lastname: Miyasaki
authors.forename: Ana Elizabete
authors.initials: AE
authors.lastname: Silva
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil; D016022:Case-Control Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D007378:Interleukins / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D013274:Stomach Neoplasms / Q000235:genetics*; D051193:Toll-Like Receptors / Q000235:genetics*; D055815:Young Adult
chemical_list: D007378:Interleukins; D051193:Toll-Like Receptors