|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1995 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1994 : ¥1,500,000 (Direct Cost : ¥1,500,000)
Genetic polymorphisms of CYPIA1 and GST1, which may play important roles in metabolic activation or detoxification of polycyclic aromatic hydrocarbons such as benzo (a) pyrene, were examined in the patients with oral squamous cell carcinomas (SCC).
1.The frequency of genotypes, Ile/Ile, Ile/Val and Val/Val, were 0.60,0.33 and 0.07, respectively in the patients with oral SCC.Comparing with non oral cancer patients or healthy Japanese population, the number of rare homozygote (Val/Val) genotype was relatively higher than those of controls.
2.Comparing the incidence of the presence of at least one GST1 gene (GST(+)) or its complete deletion (GST(-)) between oral cancer patients and controls, there was no significant difference observed (43.3% versus 46.6%).
3.When the total amounts of cigarette consumption dose were estimated among patients with different CYPIA1 genotypes, the mean value of Val/Val genotype was less than those of another genotypes.
4.Val/Val homozygotes, which is considered to be a high risk group against lung cancer induced by cigarette smoking, was found in 13.7% of the patients with SCC of lower gingiva and the dose of cigarette consumption in those patients were much less than those of another genotypes.
In conclusion, Val/Val homozygote may be also susceptible for smoking conducted lower gingival carcinoma and it is suggested that the mechanisms of carcinogenesis are not same in the each site of the oral cavity.