Meta-Analysis
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Feb 7, 2016; 22(5): 1911-1918
Published online Feb 7, 2016. doi: 10.3748/wjg.v22.i5.1911
Glutathione S-transferase M1 polymorphism and esophageal cancer risk: An updated meta-analysis based on 37 studies
Quan-Jun Lu, Ya-Cong Bo, Yan Zhao, Er-Jiang Zhao, Wolde Bekalo Sapa, Ming-Jie Yao, Dan-Dan Duan, Yi-Wei Zhu, Wei-Quan Lu, Ling Yuan
Quan-Jun Lu, Ya-Cong Bo, Wolde Bekalo Sapa, Dan-Dan Duan, Yi-Wei Zhu, Department of Nutrition and Food Hygiene, College of Public Health, Zhengzhou University, Zhengzhou 450001, Henan Province, China
Yan Zhao, Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou 450001, Henan Province, China
Er-Jiang Zhao, Wei-Quan Lu, Affiliated Tumor Hospital of Zhengzhou University, Henan Tumor Hospital, Zhengzhou 450003, Henan Province, China
Ming-Jie Yao, School of Basic Medical Sciences, Peking University, Beijing 100191, China
Ling Yuan, Department of Radiotherapy, Affiliated Tumor Hospital of Zhengzhou University, Henan Tumor Hospital, Zhengzhou 450003, Henan Province, China
Author contributions: Lu QJ, Lu WQ and Yuan L conceived and designed the study; Bo YC, Zhao Y, Zhao EJ, Duan DD and Zhu YW selected the studies, extracted the data and performed the statistical analysis; Lu QJ and Bo YC drafted the manuscript; Sapa WB and Yao MJ revised the manuscript.
Supported by Science and Technology Project of The Health Department of Henan Province, China, No. 510102050432.
Conflict-of-interest statement: The authors declare that there are no conflicts of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Ling Yuan, MD, Department of Radiotherapy, Affiliated Tumor Hospital of Zhengzhou University, Henan Tumor Hospital, No. 1 Jianshe East Rd, Erqi District, Zhengzhou 450003, Henan Province, China. hnyl2001@126.com
Telephone: +86-371-67781868 Fax: +86-371-67781868
Received: March 31, 2015
Peer-review started: April 1, 2015
First decision: June 19, 2015
Revised: October 6, 2015
Accepted: November 13, 2015
Article in press: November 13, 2015
Published online: February 7, 2016
Processing time: 295 Days and 17.4 Hours
Abstract

AIM: To evaluate the relationship between glutathione S-transferase M1 (GSTM1) polymorphism and susceptibility to esophageal cancer (EC).

METHODS: A comprehensive search of the United States National Library of Medicine PubMed database and the Elsevier, Springer, and China National Knowledge Infrastructure databases for all relevant studies was conducted using combinations of the following terms: “glutathione S-transferase M1”, “GSTM1”, “polymorphism”, and “EC” (until November 1, 2014). The statistical analysis was performed using the SAS software (v.9.1.3; SAS Institute, Cary, NC, United States) and the Review Manager software (v.5.0; Oxford, England); crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the association between the GSTM1 null genotype and the risk of EC.

RESULTS: A total of 37 studies involving 2236 EC cases and 3243 controls were included in this meta-analysis. We observed that the GSTM1 null genotype was a significant risk factor for EC in most populations (OR = 1.33, 95%CI: 1.12-1.57, Pheterogeneity < 0.000001, and I2 = 77.0%), particularly in the Asian population (OR = 1.53, 95%CI: 1.26-1.86, Pheterogeneity < 0.000001, and I2 = 77.0%), but not in the Caucasian population (OR = 1.02, 95%CI: 0.87-1.19, Pheterogeneity = 0.97, and I2 = 0%).

CONCLUSION: The GSTM1 null polymorphism may be associated with an increased risk for EC in Asian but not Caucasian populations.

Keywords: Meta-analysis; Glutathione S-transferase M1; Polymorphism; Esophageal cancer; Deletions

Core tip: Many previous studies have investigated the association between the glutathione S-transferase M1 (GSTM1) null genotype and the risk of esophageal cancer (EC), but these studies have provided controversial findings. The present study represents the largest meta-analysis to estimate the association between the GSTM1 polymorphism and EC risk. We investigated these two genotypes (GSTM1 null or GSTM1 present) in terms of EC morbidity.