Glutathione S-transferase M1 polymorphism and esophageal cancer risk: An updated meta-analysis based on 37 studies.

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, P heterogeneity < 0.000001, and I (2) = 77.0%), particularly in the Asian population (OR = 1.53, 95%CI: 1.26-1.86, P heterogeneity < 0.000001, and I (2) = 77.0%), but not in the Caucasian population (OR = 1.02, 95%CI: 0.87-1.19, P heterogeneity = 0.97, and I (2) = 0%). CONCLUSION: The GSTM1 null polymorphism may be associated with an increased risk for EC in Asian but not Caucasian populations.

XPD Lys751Gln polymorphism and esophageal cancer risk: a meta-analysis involving 2288 cases and 4096 controls.

AIM: To evaluate the association between xeroderma pigmentosum group D (XPD), genetic polymorphism Lys751Gln and esophageal cancer risk. METHODS: We searched PubMed up to September 1, 2010 to identify eligible studies. A total of 10 case-control studies including 2288 cases and 4096 controls were included in the meta-analysis. Statistical analysis was performed with Review Manage version 4.2. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the association. RESULTS: The results suggested that there is no significant association between XPD Lys751Gln polymorphism and esophageal cancer susceptibility in the overall population. However, in subgroup analysis by histology type, a significant association was found between XPD Lys751Gln polymorphism and esophageal adenocarcinoma (for CC vs AA: OR = 1.25, 95% CI = 1.01-1.55, P = 0.05 for heterogeneity). CONCLUSION: Our meta-analysis suggested that XPD Lys751Gln polymorphism may be associated with increased risk of esophageal adenocarcinoma.

[The trend of cancer mortality from 1988 to 2005 in Kaifeng county, China].

OBJECTIVE: To investigate the time trends of cancer mortality among residents in Kaifeng county, Henan province. METHODS: Data on cancer mortality from the vital registration system in Kaifeng county from 1988 to 2005 was analyzed. A total of 9543 death records (5974 males and 3567 females) due to malignant tumors were studied. A two-year-period age-specified standardized mortality rates were directly adjusted by the world standard population, and the annual percentage change (APC) of mortality were estimated by a linear logarithm regression. RESULTS: The crude cancer death rate for male was 95.09/100,000 and its age-standardized death rate was 117.41/100,000. While, the crude cancer death rate for female was 59.13/100,000 and the age-standardized death rate was 57.15/100,000. There was a significant growth tread for lung cancer (APC: 6.54%), liver cancer (5.07%) in males and breast cancer (7.04%) in females in the groups aged over 18. On the contrary, the decreasing treads for esophageal cancer in both of sexes (-7.09%, -13.53%) were also observed in this study. Meanwhile, there was no other significant changes in the trend, either in the tumor sites or mortality, was observed. CONCLUSION: In the past two decades, there has been a significant increasing trend for cancer mortality in Kaifeng county, of Henan Province. Hence, it is necessary to enhance epidemiological survey to identify risk factors at the earlier stages.