Glutathione S-transferases as risk factors in prostate cancer

Glutathione S-transferases are enzymes involved in the metabolism of carcin ogens and in the defence against reactive oxygen species, Genetic polymorph isms have been detected in glutathione S-transferases M1, T1 and P1, and so me of these polymorphisms have been associated with an increased risk of ca ncer. In a case-control study (153 cases and 288 controls) the effect of th ese genetic polymorphisms on the risk of prostate cancer was investigated. Homozygote deletion of either GSTM1 or GSTT1 was not associated with a stat istically significant increased risk, odds ratio (OR) 1.3; 95% confidence i ntervals (CI) 0.9-1.9 and 1.3; 0.8-2.2, respectively, Deletion of both GSTM 1 and GSTT1 gave a near-significant increased risk (OR 1.7; 95% CI 0.9-3.4) , Two allelic variants of GSTP1 (codon 105) have been reported. This polymo rphism was not linked to an increased risk (OR 0.8; 95% CI 0.5-1.1), Smoker s that lack either GSTM1 or GSTT1 activity had a slightly higher risk of pr ostatic cancer than smokers expressing the genes, OR 1.4 (95% CI 0.6-3.3) a nd 1.6 (0.6-3.9), respectively. Our results show that differences in enzyme s involved in the metabolism of carcinogens slightly modify prostate cancer risk, especially in people exposed to carcinogens that are detoxified by t hese enzymes. (C) 1999 Lippincott Williams & Wilkins.