Case Control Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 14, 2019; 25(34): 5152-5161
Published online Sep 14, 2019. doi: 10.3748/wjg.v25.i34.5152
Association of XPG rs2094258 polymorphism with gastric cancer prognosis
Xiao-Qin Wang, Paul D Terry, Yang Li, Yue Zhang, Wen-Jing Kou, Ming-Xu Wang
Xiao-Qin Wang, Yang Li, Yue Zhang, Wen-Jing Kou, Ming-Xu Wang, Department of Public Health, Xi’an Jiaotong University Health Science Center, Xi’an 710061, Shaanxi Province, China
Paul D Terry, Graduate School of Medicine, University of Tennessee Medical Center, Knoxville, TN 37920, United States
Author contributions: Wang XQ wrote the manuscript; Wang XQ and Terry PD analyzed the data; Li Y, Zhang Y, and Kou WJ performed the majority of experiments; Wang XQ and Wang MX designed the research; Wang MX and Terry PD revised the manuscript.
Supported by the Fundamental Research Funds for the Central Universities, No. zdyf2017007.
Institutional review board statement: This study was approved by the Institutional Review Board of Health Science Center of Xi’an Jiaotong University.
Informed consent statement: Informed consent was obtained from all study participants.
Conflict-of-interest statement: The authors declare no conflict of interest.
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/
Corresponding author: Ming-Xu Wang, PhD, Professor, Department of Public Health, Xi’an Jiaotong University Health Science Center, 76 Yanta West Road, Xi’an 710061, Shaanxi Province, China. wangmx601@mail.xjtu.edu.cn
Telephone: +86-13991815026 Fax: +86-29-82657517
Received: May 16, 2019
Peer-review started: May 16, 2019
First decision: July 21, 2019
Revised: July 25, 2019
Accepted: August 19, 2019
Article in press: August 19, 2019
Published online: September 14, 2019
Abstract
BACKGROUND

The xeroderma pigmentosum group G (XPG) gene at chromosome 13q33 consists of 15 exons, which may be related to the occurrence and development of gastric cancer (GC).

AIM

To examine the association of several common single nucleotide polymorphisms (SNPs) of the XPG gene with GC risk and survival.

METHODS

Five SNPs of XPG (rs2094258, rs751402, rs873601, rs2296147, and rs1047768) were genotyped by PCR restriction fragment length polymorphism in 956 histologically confirmed GC cases and 1012 controls in North China. GC patients were followed for survival status and, if deceased, cause of death. Logistic regression and Cox regression were used for analysing associations of XPG SNPs with risk of GC and prognosis, respectively. For rs2094258, heterozygous model (CT vs CC), homozygous model (TT vs CC), recessive model (TT vs CT + CC), and dominant model (TT + CT vs CC) were analyzed.

RESULTS

None of the examined loci were statistically associated with GC risk, although rs2296147 was marginally associated with GC risk (P = 0.050). GC patients with the rs2094258 CT + CC genotype showed worse survival than those with the TT genotype (log-rank test, P = 0.028), and patients with the CC genotype had a tendency of unfavourable prognosis compared with those with the TT + CT genotype (log-rank test, P = 0.039). The increase in C alleles of rs2094258 [hazard ratio (HR) = 1.19, 95% confidence interval (CI): 1.02-1.45, P = 0.037] were associated with the long-term survival of GC cases. Other risk factors for survival included tumor differentiation (HR = 4.51, 95%CI: 1.99-8.23, P < 0.001), lymphovascular invasion (HR = 1.97, 95%CI: 1.44-3.01, P < 0.001), and use of chemotherapy (HR = 0.81, 95%CI: 0.63-0.98, P = 0.041).

CONCLUSION

The XPG rs2094258 polymorphism may be associated with overall survival in GC patients.

Keywords: Xeroderma pigmentosum group G, Single nucleotide polymorphisms, rs2094258, Gastric cancer, Prognosis

Core tip: This study investigated the relationships between five functional single nucleotide polymorphisms of the xeroderma pigmentosum group G (XPG) (rs2094258, rs751402, rs2296147, rs1047768, and rs873601) and gastric cancer (GC) risk and survival. The results showed an association between the XPG rs2094258 polymorphism and overall survival in patients with GC. GC patients with the rs2094258 CT + CC genotype showed a worse survival than those with the TT genotype, and patients with the CC genotype had a tendency of unfavourable prognosis compared with those with the TT + CT genotype. The increase in the number of C alleles of rs2094258 was associated with the long-term survival of GC cases.