RESUMEN
The association between the microsomal epoxide hydrolase 1 gene (EPHX1) Tyr113His polymorphism and lung cancer and breast cancer risk has been reported in many recent studies, but there is no consensus among the results. Thus, we examined the association between the EPHX1 Tyr113His polymorphism and lung cancer through a meta-analysis. A comprehensive literature search was performed using the Pubmed and Embase databases. Odds ratios with 95% confidence intervals were used to assess the strength of associations. Our meta-analysis suggested that the Tyr113His polymorphism was associated with lung cancer risk in Asians under 3 genetic models, including a C vs T, CC vs TT, and recessive model. However, the risk was decreased in Caucasians under the genetic models, including a C vs T, CC vs TT, or CT vs TT, dominant, and recessive model. In contrast, there was no association with breast cancer risk for any of the genetic models. Our meta-analysis suggested that the EPHX1 Tyr113His polymorphism may be a risk factor for lung cancer in Asians, whereas it may be a decreased risk factor among Caucasians. However, this polymorphism was not found to be associated with breast cancer.
Asunto(s)
Neoplasias de la Mama/genética , Epóxido Hidrolasas/genética , Estudios de Asociación Genética , Neoplasias Pulmonares/genética , Polimorfismo de Nucleótido Simple , Alelos , Sustitución de Aminoácidos , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Masculino , Oportunidad Relativa , Sesgo de PublicaciónRESUMEN
Microsomal epoxide hydrolase 1 (EPHX1) is an important biological phase II metabolic enzyme that is extensively involved in the metabolism of diverse environmental carcinogens such as polycyclic aromatic hydrocarbons and heterocyclic amines. Many articles have reported the association between EPHX1 (Tyr113His and His139Arg) polymorphisms and esophageal cancer risk, but the results are controversial. This study aimed to identify the association between EPHX1 (Tyr113His and His139Arg) polymorphisms and esophageal cancer risk by meta-analysis. The odds ratio (OR) with 95% confidence interval (95%CI) was used to evaluate the strength of the associations. Heterogeneity was estimated by the chi-square-based Q-statistic test and the P value. Meanwhile, the random-effect or fixed-effect model was used according to the between-study heterogeneity. Begg's funnel plot and the Egger test were performed to assess the publication bias of articles. Finally, 8 case-control studies involving 1158 cases and 1868 controls for the Tyr113His polymorphism and 7 case-control studies involving 901 cases and 1615 controls for the His139Arg polymorphism were included in this meta-analysis. Meta-analysis showed that the Tyr113His polymorphism was a stronger power trend towards risk for esophageal cancer using a recessive model (CC versus CT+TT, OR = 1.204, 95%CI = 1.001-1.450, P = 0.049). However, no significant associated risk was found between the His139Arg polymorphism and esophageal cancer. These findings suggest that the Tyr113His polymorphism might be a stronger power trend towards risk for esophageal cancer. However, no evidence was found for the association between the EPHX1 His139Arg polymorphism and esophageal cancer risk.