Association of genetic polymorphisms of aldehyde dehydrogenase-2 and cytochrome P450 2E1-RsaI and alcohol consumption with oral squamous cell carcinoma.

OBJECTIVE: To investigate the association of the polymorphisms of aldehyde dehydrogenase-2(ALDH2) and CYP2E1-RsaI genes and alcohol consumption with oral squamous cell carcinoma (OSCC). METHODS: The genetic polymorphisms of ALDH2 and CYP2E1-RsaI were determined by polymorphism-polymerase chain reaction (PCR) technique in the peripheral blood leukocytes of 320 OSCC patients and 320 non-cancer controls. RESULTS: The frequencies of ALDH2 variant genotypes and CYP2E1-RsaI (c2/c2) were 70.94% and 39.06% in the OSCC group and 43.44% and 20.62% in the control group (both P<0.01). The risk of OSCC with ALDH2 variant genotypes was significantly higher than that in control group (OR=3.178, 95% CI=1.917-4.749), whereas the subjects carried with CYP2E1-RsaI (c2/c2) also had a high risk of OSCC (OR=2.467, 95%CI=1.783-4.045). Combined analysis of the polymorphisms showed that percentage of ALDH2 variant genotypes/CYP2E1-RsaI (c2/c2) in OSCC group and control group was 32.19% and 6.25%, respectively (P<0.01). Carriers of ALDH2 variant genotypes/CYP2E1-RsaI (c2/c2) had a high risk of OSCC (OR=9.792, 95%CI=3.583-12.472). The percentage of alcohol consumption was significantly higher in OSCC group than in the control group (OR=2.861, 95% CI=1.541-4.781, P<0.01), and ALDH2 variant genotypes and CYP2E1-RsaI (c2/c2) showed synergic effects with alcohol consumption for the increased risk of OSCC (OR=41.152, 95%CI=19.903-67.551). CONCLUSION: The polymorphisms of ALDH2 and CYP2E1-RsaI genes and alcohol consumption, independently and synergically, increase the risk of OSCC.