title: Relationships betweenMGMTpromoter methylation and gastric cancer: a meta-analysis.
abstract: A DNA repair enzyme, O6-methylguanine-DNA methyltransferase (MGMT), plays an important role in the development of gastric cancers. However, the role ofMGMTpromoter methylation in the occurrence of gastric cancer and its relationships with clinicopathologic characteristics has not been fully clarified. Thus, we performed a meta-analysis to evaluate the associations betweenMGMTpromoter methylation and gastric cancer. Electronic databases, including PubMed and Web of Science, were used to systematically search related clinical studies published in English until April 1, 2016. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated to evaluate the associations betweenMGMTpromoter methylation and gastric cancer risk or clinicopathologic characteristics. A total of 16 studies including 1,935 patients and 1,948 control persons were included in the analysis. Our study suggested thatMGMTpromoter methylation frequency was associated with gastric cancer (OR=3.46, 95% CI: 2.13-5.61,P<0.001). Moreover, the frequency ofMGMTpromoter methylation in the no lymph node metastasis group was lower than that in lymph node metastasis group, with marginal significance (OR=0.65, 95% CI: 0.42-1.01,P=0.05). Additionally, the methylation rate of theMGMTpromoter was much lower in patients without distant metastases than in those with metastases (OR=0.27, 95% CI: 0.18-0.40,P<0.001). No significant association ofMGMTpromoter methylation with Lauren classification, tumor location, tumor invasion, orHelicobacter pyloriinfection was found. In conclusion, the methylation status of theMGMTpromoter was related to gastric cancer risk, distant metastasis, and lymph node metastasis, which indicates thatMGMTpromoter methylation may play an important role in gastric cancer development.
authors: Department of Laboratory Medicine, Center for Gene Diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.
authors: Dan
authors: D
authors: Yu
authors: Department of Laboratory Medicine, Center for Gene Diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.
authors: Tao
authors: T
authors: Cao
authors: Department of Laboratory Medicine, Center for Gene Diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.
authors: Ya-Di
authors: YD
authors: Han
authors: Department of Laboratory Medicine, Center for Gene Diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.
authors: Fu-Sheng
authors: FS
authors: Huang
keywords: cancer risks; gastric cancer; tumor suppressor gene