TLR4 promoter rs1927914 variant contributes to the susceptibility of esophageal squamous cell carcinoma in the Chinese population

Jiaying Li; Hongjiao Wu; Hui Gao; Ruihuan Kou; Yuning Xie; Zhi Zhang; Xuemei Zhang

doi:10.7717/peerj.10754

TLR4 promoter rs1927914 variant contributes to the susceptibility of esophageal squamous cell carcinoma in the Chinese population

PeerJ. 2021 Feb 1:9:e10754. doi: 10.7717/peerj.10754. eCollection 2021.

Authors

Jiaying Li^{1

2}, Hongjiao Wu¹, Hui Gao¹, Ruihuan Kou³, Yuning Xie^{1

2}, Zhi Zhang³, Xuemei Zhang^{1

2}

Affiliations

¹ School of Public Health, North China University of Science and Technology, Tangshan, China.
² College of Life Science, North China University of Science and Technology, Tangshan, China.
³ Affliated Tangshan Gongren Hospital, North China University of Science and Technology, Tangshan, China.

Abstract

Background: Toll-like receptor 4 (TLR4), as a key regulator of both innate and acquired immunity, has been linked with the development of various cancers, including esophageal cancer. This study aims to analyze the association of potential functional genetic polymorphisms in TLR4 with the risk of esophageal cancer.

Methods: This case-control study involved in 480 ESCC patients and 480 health controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to genotype TLR4 rs1927914 polymorphism. Taqman probe method was used to determine the genotypes of TLR4 rs11536891 and rs7873784 variants. The relationship between TLR4 genetic variation and ESCC risk was analyzed by Logistic regression model by calculating the odds ratio (OR) and 95% confidence interval (95% CI).

Results: Compared with TLR4 rs1927914 AA genotype carriers, GG carriers had a lower ESCC risk (OR = 0.59, 95% CI [0.38-0.93], P = 0.023). Stratification analysis by age showed that TLR4 rs1927914 GG could affect the risk of ESCC in elderly people (OR = 0.59, 95% CI [0.36-0.97]). Smoking stratification analysis indicated that rs1927914 GG carriers were related to ESCC susceptibility among non-smokers (OR = 0.36, 95% CI [0.18-0.73]). Dual luciferase reporter assay suggested that rs1927914 G-containing TLR4 promoter displayed a 1.76-fold higher luciferase activity than rs1927914 A-containing counterpart in KYSE30 cells. Electrophoretic mobility shift assay (EMSA) showed the KYSE30 cell nuclear extract was able to bind the probe with rs1927914 G allele and this DNA-protein interaction could be eliminated by competition assays with unlabeled rs1927914 G probe, which indicating that the binding is sequence-specific. Our results also showed that TLR4 rs7873784 (G>C) and rs11536891 (T>C) conformed to complete genetic linkage. The genotype distributions of TLR4 rs11536891 variant among ESCC patients and normal controls have no statistical significance.

Conclusion: The TLR4 rs1927914 variant contributes to the ESCC risk by effecting the promoter activity.

Keywords: Esophageal squamous cell carcinoma; Innate immune; Single nucleotide polymorphism; TLR4.

Grants and funding

This work was supported by the Key Project of Natural Science Foundation of Hebei province of China (H2017209233 to Xuemei Zhang), the Leader talent cultivation plan of innovation team in Hebei province (LJRC001 to Xuemei Zhang) and the National Natural Science Foundation of China (81101483 to Xuemei Zhang). There was no additional external funding received for this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.