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

Purpose: 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 355Tand 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 G355C4326G21293, haplotypes T355C4326G21293 (adjusted OR = 1.809, P <0.001), G355C4326C21293 (adjusted OR =1.644, P = 0.044), and T355C4326C21293 (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.