GSTP1 and prostate cancer: When the data were analyzed in subgroups of subjects stratified by smoking status, we did not find that GSTP1 Ile105Val polymorphism was significantly associated with prostate cancer risk among smokers (Val/Val+Val/Ile vs. Ile/Ile: OR = 0.90, 95% CI = 0.68–1.18, P = 0.43; Table S2), and among non-smokers (Table S2).