title: Quantitative assessment of the association between GSTM1 null genotype and laryngeal cancer risk.
abstract: Previous studies investigating the association between glutathione S-transferase M1 (GSTM1) null genotype and laryngeal cancer risk reported controversial results. Thus, a meta-analysis was performed to clarify the effect of GSTM1 null genotype on laryngeal cancer risk. A literature search was performed for all possible studies. We estimated summary odd ratio (OR) with its 95 % confidence interval (95 % CI) to assess the association. Subgroup analyses were performed by ethnicity or the sample size. 24 individual case-control studies involving a total of 2,809 laryngeal cancer cases and 4,478 controls were finally included into this meta-analysis. Meta-analyses of total 24 studies showed the GSTM1 null genotype was significantly associated with increased laryngeal cancer risk (random-effects OR = 1.44, 95 % CI 1.19-1.73, P < 0.001). Subgroup analyses by ethnicity showed that the GSTM1 null genotype was associated with increased laryngeal cancer risk in both Caucasians (fixed-effects OR = 1.17, 95 % CI 1.04-1.33, P = 0.012) and Asians (random-effects OR = 1.89, 95 % CI 1.28-2.77, P = 0.001). Also, subgroup analyses by sample size also further identified this association above. The cumulative meta-analyses showed a trend of more obvious association between GSTM1 null genotype and increased risk of laryngeal cancer as information accumulated by year. Meta-analysis of available data suggests that GSTM1 null genotype contributes to increased laryngeal cancer risk in both Caucasians and East Asians.
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, The Second Affiliated Hospital of Harbin Medical University, 246 Xue Fu Road, Harbin 150081, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Xiao
authors.forename: Minghua
authors.initials: M
authors.lastname: Li
authors.forename: Linli
authors.initials: L
authors.lastname: Tian
authors.forename: Bin
authors.initials: B
authors.lastname: Zha
authors.forename: Ming
authors.initials: M
authors.lastname: Liu
authors.forename: Hongchao
authors.initials: H
authors.lastname: Yao
mesh_terms: D020022:Genetic Predisposition to Disease; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D007822:Laryngeal Neoplasms / Q000235:genetics*; D011110:Polymorphism, Genetic
chemical_list: D005982:Glutathione Transferase