Polymorphisms of Glutathione S-Transferase Mu 1 (GSTM1), Theta 1 (GSTT1), and Pi 1 (GSTP1) Genes and Epithelial Ovarian Cancer Risk

Background : Exposure of ovarian cells to estrogen, which is detoxified by glutathione S-transferases (GSTs), has been associated with epithelial ovarian cancer (EOC) development. Objectives : We tested in this study whether the GSTM1 , GSTT1 and GSTP1 Ile105Val polymorphisms alter the risk of EOC. Materials and methods : Genomic DNA from 132 EOC patients and 132 controls was analyzed by polymerase chain reaction and restriction fragment length polymorphism methods. The differences between groups were analyzed by χ 2 or Fisher’s exact test. Results : The frequencies of GSTP1 Ile/Ile (57.6% versus 45.5%, P = 0.03), GSTM1 null plus GSTP1 Ile/Ile (43.5% versus 25.8%; P = 0.03) and GSTM1 null plus GSTT1 null plus GSTP1 Ile/Ile (30.3% versus 7.7%; P = 0.007) genotypes were higher in patients than in controls. Individuals with the respective genotypes had a 1.80 (95% CI: 1.06–3.06), 2.38 (95% CI: 1.08–5.24) and 11.28 (95%CI: 1.95–65.30)-fold increased risks of EOC than those with the remaining genotypes. Conclusions : Our data present preliminary evidence that GSTM1 , GSTT1 and GSTP1 polymorphisms, particularly in combination, constitute important inherited EOC determinants in individuals from Southeastern Brazil.