OBJECTIVE: To test the hypothesis whether polymorphism in estrogen-metabolizing genes, COMT and CYP17, impacts on the risk of breast cancer among Chinese women. METHODS: COMT (Val158Met) and CYP17 (T1931C) polymorphisms were detected by PCR-based restriction fragment length polymorphism analysis in 250 breast cancer patients and 250 frequency-matched normal controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression. RESULTS: COMT Met/Met genotype was found in 10.4% of breast cancer patients, which was significantly higher (P = 0.03) than that in controls (5.2%). Women with Met/Met genotype showed 2-fold increased risk for breast cancer (adjusted OR 2.1, 95% CI 1.1 - 4.5) compared with those with Val/Val or Val/Met genotypes. Stratified analysis showed that the elevated risk of breast cancer, associating with the COMT Met/Met genotype, was evident only among premenopausal women (adjusted OR 4.1, 95% CI 1.2 - 17.3) but not among postmenopausal women (adjusted OR 1.3, 95% CI 0.5 - 3.5). There was no significant difference in the distribution of CYP17 genotypes between breast cancer patients and the control subjects (P = 0.83). CONCLUSION: The allele encoding for low activity COMT, but not CYP17, may be a genetic risk factor for breast cancer among Chinese women.
OBJECTIVE: To test the hypothesis whether polymorphism in estrogen-metabolizing genes, COMT and CYP17, impacts on the risk of breast cancer among Chinese women. METHODS:COMT (Val158Met) and CYP17 (T1931C) polymorphisms were detected by PCR-based restriction fragment length polymorphism analysis in 250 breast cancerpatients and 250 frequency-matched normal controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression. RESULTS:COMT Met/Met genotype was found in 10.4% of breast cancerpatients, which was significantly higher (P = 0.03) than that in controls (5.2%). Women with Met/Met genotype showed 2-fold increased risk for breast cancer (adjusted OR 2.1, 95% CI 1.1 - 4.5) compared with those with Val/Val or Val/Met genotypes. Stratified analysis showed that the elevated risk of breast cancer, associating with the COMT Met/Met genotype, was evident only among premenopausal women (adjusted OR 4.1, 95% CI 1.2 - 17.3) but not among postmenopausal women (adjusted OR 1.3, 95% CI 0.5 - 3.5). There was no significant difference in the distribution of CYP17 genotypes between breast cancerpatients and the control subjects (P = 0.83). CONCLUSION: The allele encoding for low activity COMT, but not CYP17, may be a genetic risk factor for breast cancer among Chinese women.
Authors: Lori C Sakoda; Christie Blackston; Jennifer A Doherty; Roberta M Ray; Ming Gang Lin; Helge Stalsberg; Dao Li Gao; Ziding Feng; David B Thomas; Chu Chen Journal: Cancer Epidemiol Biomarkers Prev Date: 2008-05 Impact factor: 4.254
Authors: Jiun-Horng Chang; Dorota M Gertig; Xiaoqing Chen; Gillian S Dite; Mark A Jenkins; Roger L Milne; Melissa C Southey; Margaret R E McCredie; Graham G Giles; Georgia Chenevix-Trench; John L Hopper; Amanda B Spurdle Journal: Breast Cancer Res Date: 2005-05-12 Impact factor: 6.466