Meta-Analysis
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World J Gastroenterol. Nov 28, 2014; 20(44): 16765-16773
Published online Nov 28, 2014. doi: 10.3748/wjg.v20.i44.16765
Xeroderma pigmentosum group D polymorphisms and esophageal cancer susceptibility: A meta-analysis based on case-control studies
Rong Yang, Chong Zhang, Armah Malik, Zhi-Da Shen, Jian Hu, Yi-He Wu
Rong Yang, Department of Radiology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang Province, China
Chong Zhang, Armah Malik, Jian Hu, Yi-He Wu, Department of Thoracic Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang Province, China
Zhi-Da Shen, College of Medicine, Zhejiang University, Hangzhou 310058, Zhejiang Province, China
Author contributions: Wu YH and Hu J designed the research; Yang R and Zhang C performed the research; Yang R, Malik A and Shen ZD wrote the paper.
Correspondence to: Yi-He Wu, MD, Department of Thoracic Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, No. 79 Qingchun Road, Hangzhou 310003, Zhejiang Province, China. drwuyihe@163.com
Telephone: +86-571-87236847 Fax: +86-571-87236847
Received: March 21, 2014
Revised: May 5, 2014
Accepted: July 29, 2014
Published online: November 28, 2014
Abstract

AIM: To clarify the effects of the xeroderma pigmentosum group D (XPD) Asp312Asn and Lys751Gln gene polymorphisms on the risk of esophageal cancer (EC).

METHODS: A computerised literature search was conducted to identify the relevant studies from the PUBMED and EMBASE databases, reviews, and reference lists of relevant articles. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the associations between the XPD Asp312Asn and/or Lys751Gln polymorphisms and EC susceptibility. Statistical analyses were performed using the software Stata 12.0. A fixed or random effects model was selected based on a heterogeneity test. Publication bias was estimated using funnel plots and Egger’s linear regression method. Subgroup analyses were performed based on histological type and ethnicity.

RESULTS: Thirteen case-control studies with a total of 10 comparisons for the Asp312Asn polymorphism, including 2373 cases and 3175 controls, and 15 comparisons for the Lys751Gln polymorphism, including 3226 cases and 5237 controls, were recruited for the meta-analysis. In terms of the XPD Asp312Asn polymorphism, significantly increased EC risks were identified in the Asp/Asn vs Asp/Asp comparison (OR = 1.17, 95%CI: 1.02-1.33, P = 0.03) and in the dominant-model comparison (Asn/Asn+Asp/Asn vs Asp/Asp: OR = 1.18, 95%CI: 1.04-1.34, P = 0.01). However, no significant associations were found in the Asn/Asn vs Asp/Asp comparison (OR = 1.30, 95%CI: 1.00-1.70, P = 0.05) or in the recessive-model comparison (Asn/Asn vs Asp/Asn + Asp/Asp: OR = 1.17, 95%CI: 0.91-1.50, P = 0.22). In terms of the XPD Lys751Gln polymorphism, a significant association with EC susceptibility was found under the recessive model (Gln/Gln vs Lys/Gln+Lys/Lys: OR = 1.21, 95%CI: 1.02-1.43, P = 0.03). However, no associations were identified in the other comparisons (co-dominant model: Lys/Gln vs Lys/Lys: OR = 1.11, 95%CI: 0.94-1.31, P = 0.20; Gln/Gln vs Lys/Lys: OR = 1.31, 95%CI: 0.98-1.75, P = 0.07; dominant model: OR = 1.14, 95%CI: 0.96-1.35, P = 0.14).

CONCLUSION: The results of this meta-analysis suggest that the XPD Asp312Asn and Lys751Gln gene polymorphisms are associated with a significantly increased risk for EC.

Keywords: Esophageal cancer, Xeroderma pigmentosum group D, Polymorphism, Meta-analysis

Core tip: To clarify the effects of xeroderma pigmentosum group D (XPD) gene polymorphisms on the risk of esophageal cancer (EC), we performed a meta-analysis of all of the case-control studies that evaluated the association between the genetic polymorphisms of XPD (Asp312Asn and Lys751Gln) and EC susceptibility. Thirteen case-control studies were recruited in the meta-analysis. For the XPD Asp312Asn polymorphism, significantly increased EC risks were found in the Asp/Asn vs Asp/Asp comparison and in the dominant model comparison. For the XPD Lys751Gln polymorphism, a significant association between the XPD Lys751Gln polymorphism and EC susceptibility was found under the recessive model.