title: Lack of influence of glutathione S-transferase genotype profile on cancer susceptibility in smokers and nonsmokers.
abstract: BACKGROUND
  The glutathione-S-transferase (GST) gene family has an important role in the biotransformation and detoxification of different xenobiotics and endogenous carcinogens. GST profile has been associated to an increased risk for several types of tumors in different populations, but ethnic stratification makes data interpretation difficult. The Brazilian population represents a unique model in which the types and frequencies of GST gene polymorphisms are less influenced by ethnicity.
  
  
  METHODS
  To evaluate the influence of GST profile in different age and gender groups regarding the risk of developing cancer and its relationship to smoking habit, the GSTT1, GSTM1, and GSTP1 genotypes of 785 Brazilian patients with cancer and 873 cancer-free controls paired on the basis of sex, age, ethnicity, diet and exercise routine, lifetime occupational history, smoking history, general health conditions, and previous diseases were compared.
  
  
  RESULTS
  A univariate logistic regression analysis demonstrated that age over 45 years (p=0.0417) and smoking (p=0.0015) were related to cancer. Multivariate analysis confirmed the importance of advanced age in susceptibility to cancer (p=0.0001). It was also observed that smoking significantly increased the risk of cancer among individuals over 45 years old (OR: 1.825, 95%CI: 1.241-2.682). However, no correlation between risk of cancer, smoking habit, age, or gender and any of the studied GST polymorphisms was found.
  
  
  CONCLUSIONS
  It is suggested that GST profile does not exert an important impact on the influence of tobacco smoking on cancer risk.
authors.affiliation: Laboratory of Cancer Molecular Genetics and Division of Oncology, Faculty of Medical Sciences, State University of Campinas-Unicamp, Sao Paulo, Brazil.
authors.forename: Aline Castaldi
authors.initials: AC
authors.lastname: Sampaio
authors.forename: Elaine Cristina
authors.initials: EC
authors.lastname: Morari
authors.forename: Natassia Elena
authors.initials: NE
authors.lastname: Bufalo
authors.forename: Janaina Luisa
authors.initials: JL
authors.lastname: Leite
authors.forename: Carmen Silvia Passos
authors.initials: CS
authors.lastname: Lima
authors.forename: Laura S
authors.initials: LS
authors.lastname: Ward
mesh_terms: D000367:Age Factors; D001938:Brazil; D005260:Female; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D016015:Logistic Models; D008297:Male; D009369:Neoplasms / Q000139:chemically induced / Q000235:genetics*; D011110:Polymorphism, Genetic; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects*
chemical_list: D005982:Glutathione Transferase