A Case-Control Study of the Association between Glutathione S-transferase (GST) M1 and T1 Genetic Polymorphism and Breast Cancer in Korean Women: Preliminary report / 대한암학회지

ABSTRACT

PURPOSE: A hospital-based case-control study was conducted to evaluate the role of glutathione-S-transferase (GST) Ml and Tl genetic polymorphism for developing breast cancer in Korea. MATERIALS AND METHODS: Histologically confirmed incident cases of breast cancer (n=176) were selected from inpatients at the Department of General Surgery, Seoul National University Hospital (SNUH), Borame hospital, and Asan Medical Center from 1994 to 1998. Women with no self-reporting past history of any malignancies who were selected from the inpatients at the same department at three hospitals during the same period served as controls (n 118). Information on the life-styles including reproductive factors were obtained by interview using questionnaire. Age and education adjusted odds ratio and 95% confidence interval were estimated by unconditional linear logistic regression. RESULTS: These subjects had similar risk factors for developing breast cancer to general Korean population based on other epidetniologic studies previously performed in Korea. GSTI1 null type showed a borderline significance relation in the breast cancer risk (adjusted OR=1.6, 95% CI=0.96-2.62), however, GSTM1 null type was not significant (adjusted OR=1.1, 95% CI=0.67-1.80). Particularly noteworthy was an borderline increasing tendency (p<0.1) of the breast cancer risk with the risk null genotypes assessed by multivariate logistic regression model after adjusting age and education the putative low-risk genotype with both GSTM1 & GSTT1 wild type, OR=1.0; one putative high risk genotype with GSTM1 null or GSTMl null type, OR=1.9 (95% CI=0.92-3.74); all two putative high risk genotype with both GSTM1 & GSTT1 null type, OR=2.0 (95% CI=0.89-4.68). CONCLUSIONS: These findings suggest that both GSTMl and GSTT1 null type might be the risk factor of developing breast cancer in Korean women. Further investigation with larger sample size should be needed to provide more concrete information on the role of GST genetic polymorphism in breast cancer.