Genetic polymorphism of N-acetyltransferase 2 in the susceptibility to laryngeal squamous cell carcinoma.

Background: The purpose of this study was to investigate whether polymorphism of N-acetyltransferase 2 (NAT2) genotypes are associated with the risk of laryngeal squamous cell carcinoma (SCC).

Methods: The study group consisted of 45 white patients with laryngeal SCC (42 men, with a mean age of 54 years [range, 37-70 years] and three women, with a mean age of 47 years [range, 32-55 years]) and 104 control subjects (68 men and 36 women; mean age, 50 years; range, 28-73 years). All of the patients were primarily treated with surgical intervention. Blood samples (5 mL) were obtained before surgery or from the patients under follow-up to 5 years after surgery (mean follow-up, 27 months; range, 6-48 months). DNA was extracted from the lymphocytes by high pure template preparation kit. NAT2*5A, NAT2*6A, NAT2*7A/B, and NAT2*14A were detected by use of LightCycler-NAT2 mutation detection kit by real-time polymerase chain reaction with Light Cycler instruments. The association between NAT2 polymorphisms and laryngeal SCC was prospectively modeled through multivariate logistic regression analysis.

Results: We found that the risk of laryngeal SCC was 7.3-fold higher in individuals with NAT2*5 mutant allele, 3.8-fold higher in subjects with NAT2*6 heterozygote allele, and 38.3-fold higher in NAT2*6 mutant allele. We also found that individuals with NAT2*7 heterozygote allele had a 0.2-fold less risk for the development of laryngeal SCC (p = .018).

Conclusion: In this population, patients with NAT2*5 mutant and *6 heterozygous and mutant genotypes had a significantly higher risk for development of laryngeal SCC.