Aim of study: Several studies have evaluated the correlation between glutathione S-transferase mu-1 (GSTM1), GST theta-1 (GSTT1) polymorphisms and oral cancer in Chinese people. However, the results are inconsistent. To assess the effects of GSTM1, GSTT1 null genotypes on the risk for development of oral cancer in the Chinese population, a meta-analysis was performed.
Materials and methods: Studies were identified using PubMed and Chinese databases through February 2016. The associations were assessed with pooled odds ratios (ORs) and 95% confidence intervals (CIs).
Results: This meta-analysis included six studies with 1306 oral cancer cases and 1484 controls. In the overall analysis, no significant association between GSTM1, GSTT1 polymorphisms and oral cancer was found in the Chinese population. In the subgroup analyses by geographic areas and source of controls, significant risk was found between GSTM1 null genotype and oral cancer in Mainland China (OR = 2.715, 95% CI = 2.17-3.38), but not in Taiwan China.
Conclusion: Our meta-analysis suggested that GSTM1 null genotype might be associated with an increased risk of developing oral cancer in individuals from Mainland China.
Keywords: Glutathione S-transferase mu-1; glutathione S-transferase theta-1; meta-analysis; oral cancer; polymorphism.