Effects of the Genetic Polymorphisms of CYP1A1 and GSTP1 on the Risk of Laryngeal Cancer in Koreans / 대한이비인후과학회지

BACKGROUND AND ackground and Objectives: Smoking has been reported as an important risk factor of laryngeal cancer. Cytochrome P450 1A1 (CYP1A1) and glutathione S-transferase P1 (GSTP1) are genes that encode enzymes which are involved in the metabolism of carcinogens in cigarette smoke. In this study, we statistically tested the significances of smoking and genotypes of CYP1A1 and GSTP1 as risk factors of laryngeal cancer. MATERIALS AND METHOD: In this case-control study, 84 pathologically proven laryngeal cancer patients and 168 age- and sex-matched controls were included as the study subjects. Information on smoking habit was collected using a self-administered questionnaire, and CYP1A1 and GSTP1 genotypes were analyzed using PCR-RFLP method. Chi-square test, Student's t-test and conditional logistic analysis were used to test statistical significance. RESULTS: Smoking was turned out to be a significant risk factor of laryngeal cancer both in univariate and multivariate analyses. The CYP1A1 Ile/Ile genotype was significant in the univariate test, but the statistical significance disappeared in the multivariate conditional logistic model including smoking. The odds ratio (95% confidence interval) of GSTP1 A/A genotype for laryngeal cancer was 0.71 (0.38, 1.33), which was not statistically significant. CONCLUSION: Smoking is the most potent risk factor among the three factors, and the genotypes of CYP1A1 and GSTP1 would not be major risk factors for laryngeal cancer in Koreans.

Effects of Genetic Factor, Life Styles, and Diet on Urinary Hippuric Acid Excretion in Toluene Exposed Workers / 대한산업의학회지

OBJECTIVES: The purpose was to investigate the distributions and the effects of genetic polymorphism of aldehyde dehydrogenase 2(ALDH2), cytochrome P450 1A1(CYP1A1), and cytochrome P450 2E1(CYP2E1) on the toluene metabolism. METHODS: The subjects consisted of 160 workers who were exposed to toluene in different industries such as paint manufacturing, painting on steel and wood products, printing, bonding, and coating. The exposed toluene level was monitored by passive air sampler, and the questionnaire variables were age, sex, smoking, drinking, previous nights drinking, use of personal protective equipment, work duration, and taking benzoic acid containing food. The urinary hippurric acid collected in the end of shift was corrected by urinary creatinine concentration. The genotypes of ALDH2, CYP1A1, and CYP2E1 were investigated using polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) methods with DNA extracted from venous blood. RESULTS: The geometric mean and the geometric standard deviation of urinary hippuric acid concentration were 0. 44 g/g creatinine and 2. 80. The urinary hippuric acid concentration was significantly related to personal exposed toluene level among personal exposed toluene level, use of personal protective equipment, and benzoic acid containing food diet. The slope differences of the regression for ALDH2, CYP1A1, and CYP2El genetic polymorphism, age, smoking, and work duration tended to be significant. In multiple regression analysis, the regression coefficient of toluene, ALDH2, CYP1A1, CYP2E1 genetic polymorphism were significant. CONCLUSIONS: Prom the above results, urinary hippuric acid level after toluene exposure was significantly affected by the genetic polymorphism of ALDH2, CYP1A1, CYP2E1. It is needed further investigation of the urinary hippuric acid level considering the effect of genetic polymorphism.