title: Effects of SNPs (CYP1B1*2 G355T, CYP1B1*3 C4326G, and CYP2E1*5 G-1293C), smoking, and drinking on susceptibility to laryngeal cancer among Han Chinese.
abstract: OBJECTIVE
  This study was conducted to explore the effects of genetic polymorphisms (CYP1B1*2 G355T, CYP1B1*3 C4326G, and CYP2E1*5 G-1293C) and environmental factors (smoking and drinking) on susceptibility to laryngeal cancer in a Han Chinese study group.
  
  
  METHODS
  This case-control study included 552 Han Chinese patients diagnosed with laryngeal cancer and 666 healthy control subjects of the same ethnicity, similar age, and gender. Genetic polymorphisms were examined using multi-PCR and Matrix Assisted Laser Desorption Ionization - Time of Flight (MALDI-TOF MS) methodology. The association of these genetic and environmental factors with susceptibility to laryngeal cancer was evaluated using a statistical approach.
  
  
  RESULTS
  The frequencies of all three polymorphisms in the patient cohort were significantly different from those in the control cohort. Compared to the control cohort, carriers of variant alleles of CYP1B1*2 355T and CYP2E1*5 -1293C showed a higher risk for developing laryngeal cancer (for CYP1B1*2 355T, adjusted OR = 2.657, P <0.001; for CYP2E1*5 -1293C, adjusted OR = 1.938, P <0.001), while carriers of mutation allele CYP1B1*3 4326G showed a lower risk (adjusted OR = 0.562, P <0.001). Joint effects of these polymorphisms were observed. When compared to haplotype G355C4326G-1293, haplotypes T355C4326G-1293 (adjusted OR = 1.809, P <0.001), G355C4326C-1293 (adjusted OR = 1.644, P = 0.044), and T355C4326C-1293 (adjusted OR = 3.104, P <0.001) were associated with a significantly higher laryngeal cancer risk. The adjusted ORs for non-smokers, non-drinkers, smokers, and drinkers with the GT/TT genotype at CYP1B1*2 G355T were 2.190 (P = 0.006), 2.008 (P = 0.001), 5.875 (P <0.001), and 4.518 (P <0.001), respectively.
  
  
  CONCLUSIONS
  CYP1B1*2 355T and CYP2E1*5 -1293C are associated with an increased laryngeal cancer risk, while CYP1B1*3 4326G is associated with a decreased risk. These polymorphisms showed joint effects on laryngeal cancer risk. Smoking and drinking showed collaborative effects with two high risk alleles (CYP1B1*2 355T and CYP1B1*3 4326G) for promoting laryngeal cancer risk.
authors.affiliation: School of Basic Medicine, Wenzhou Medical University, Wenzhou, China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Jin
authors.affiliation: The Second Affiliated Hospital of Wenzhou medical University, Wenzhou, China.
authors.forename: Faming
authors.initials: F
authors.lastname: Lin
authors.affiliation: The Second Affiliated Hospital of Wenzhou medical University, Wenzhou, China.
authors.forename: Shiyu
authors.initials: S
authors.lastname: Liao
authors.affiliation: Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical University, Wenzhou, China.
authors.forename: Qiyu
authors.initials: Q
authors.lastname: Bao
authors.affiliation: The Second Affiliated Hospital of Wenzhou medical University, Wenzhou, China.
authors.forename: Liyan
authors.initials: L
authors.lastname: Ni
mesh_terms: D000428:Alcohol Drinking / Q000009:adverse effects / Q000235:genetics*; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D016022:Case-Control Studies; D065633:Cytochrome P-450 CYP1B1 / Q000235:genetics*; D019392:Cytochrome P-450 CYP2E1 / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D007822:Laryngeal Neoplasms / Q000209:etiology / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012306:Risk; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects / Q000235:genetics*
chemical_list: D019392:Cytochrome P-450 CYP2E1; C585496:CYP1B1 protein, human; D065633:Cytochrome P-450 CYP1B1