The association of the CYP1A1 Ile462Val polymorphism with head and neck cancer risk: evidence based on a cumulative meta-analysis.
OBJECTIVE
The aim of this study was to address the association between the Ile462Val polymorphism in the gene encoding cytochrome P450 1A1 (CYP1A1) and the risk of head and neck cancer (HNC).


METHODS
The Medline/PubMed, EMBASE, and Web of Science databases were searched. The strength of the association was evaluated by calculating the odds ratio (OR) with a 95% confidence interval (CI).


RESULTS
Overall, we observed an increased risk of HNC in patients with the Ile/Val+Val/Val genotype compared to those with the Ile/Ile genotype among the 6,367 cases and 6,395 controls evaluated in the 34 eligible studies, with a pooled OR of 1.284 (95% CI: 1.119-1.473). In addition, we observed an increased risk of HNC in patients with the Ile/Val+Val/Val genotype compared to those with the Ile/Ile genotype in the subgroup analyses (OR =1.362, 95% CI: 1.102-1.685 for laryngeal cancer; OR =1.519, 95% CI: 1.253-1.843 for pharyngeal cancer; OR =1.371, 95% CI: 1.111-1.693 for Asians; and OR =1.329, 95% CI: 1.138-1.551 for patients in studies using hospital-based controls).


CONCLUSIONS
This cumulative meta-analysis suggests that the CYP1A1 Ile462Val polymorphism might contribute to the risk of HNC, particularly for pharyngeal cancer and laryngeal cancer.
Department of Toxicology, Henan Center for Disease Control and Prevention, Zhengzhou, People's Republic of China; Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine, Xinxiang Medical University, Xinxiang, People's Republic of China.
Yadong
Y
Wang
Department of Epidemiology, School of Public Health, Zhengzhou University, Zhengzhou, People's Republic of China.
Haiyan
H
Yang
Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine, Xinxiang Medical University, Xinxiang, People's Republic of China.
Guangcai
G
Duan
Department of Toxicology, Henan Center for Disease Control and Prevention, Zhengzhou, People's Republic of China.
Haiyu
H
Wang
CYP1A1; head and neck cancer; laryngeal cancer; oral cancer; pharyngeal cancer; polymorphism; risk