Association of the IL-1RN variable number of tandem repeat polymorphism and Helicobacter pylori infection: A meta-analysis

Interleukin-1β and Interleukin-1 receptor antagonist gene polymorphism in pediatric patients with Helicobacter pylori-associated chronic gastritis

BACKGROUND

The severity of Helicobacter pylori infection is determined by the interplay between bacterial virulence, host genetic and environmental factors. This study aimed to identify interleukin-1 beta (IL-1β) and interleukin receptor antagonist (IL-1RN) gene polymorphisms and their associations with H. pylori infection, and severity of chronic gastritis in Egyptian children.

METHODS

A case control study was conducted on 100 children (50 H. pylori positive and 50 controls). Genotyping of IL-1β-31 gene was done by PCR-CTPP (confronting two-pair primers), of IL-1β-511 was performed using allele specific PCR, and investigation of the variable number tandem repeat polymorphism of the IL-1RN gene was done by PCR.

RESULTS

The genotype C/T of IL1β-511 was the predominant genotype (36/50; 72%) among H. pylori positive cases (p ≤ 0.001). The presence of C/T genotype at position 511 of IL1β was associated with increased risk of infection with H. pylori (p ≤ 0.001, odds ratio = 6.612) and with more severe disease (p = 0.004, odds ratio = 8.333). No association of IL-1β-31 or IL-1RN gene polymorphisms with H. pylori infection or with risk of severe gastric diseases was found. Children who carry two polymorphisms are almost four times at risk for development of H. pylori infection (p = 0.026, odds ratio = 3.937).

CONCLUSIONS

Polymorphism at position -511 of IL1β gene is associated with increased risk of H. pylori infection as well as of severe corpus gastric disease in Egyptian children. This population should be considered a high-risk group, which needs regular gastric endoscopic surveillance, and should be target for H. pylori eradication. Lay summaryThe genotype C/T of IL1β-511 gene was the predominant genotype (36/50; 72%) among H. pylori positive children. Polymorphism at position -511 of IL1β gene is associated with increased risk of Helicobacter pylori infection as well as of severe corpus gastric disease in Egyptian children. No association of IL-1β-31 or IL-1RN gene polymorphisms with H. pylori infection or with risk of severe gastric diseases in Egyptian children.

IL1RN Polymorphisms Are Associated with a Decreased Risk of Esophageal Cancer Susceptibility in a Chinese Population

BACKGROUND

Recent evidence suggested that IL1RN (interleukin-1 receptor antagonist) polymorphisms increased the susceptibility to cancers. The present study aimed to evaluate whether IL1RN was related to esophageal cancer susceptibility in a Northwest Han Chinese population.

METHODS

The case-control study was conducted on 384 esophageal cancer patients and 499 healthy controls. We successfully genotyped four SNPs distributed in IL1RN. The Gene Expression Profiling Interactive Analysis (GEPIA) database was used to observe the expression of IL1RN in esophageal cancer tissues and normal tissues. RegulomeDB and HaploReg v4.1 were used to calculate possible functional effects of the polymorphisms. We also used genetic models to detect any potential association between IL1RN variants and esophageal cancer risk.

RESULTS

In our study, rs3181052 was associated with a reduced risk of esophageal cancer in the codominant (odds ratio [OR] = 0.70, 95% confidence interval [CI] 0.52-0.93, p = 0.040), the dominant (OR = 0.75, 95% CI 0.57-0.99, p = 0.041), and the overdominant (OR = 0.71, 95% CI 0.54-0.93, p = 0.012) model. The rs452204 was associated with a 0.76-fold (OR = 0.76, 95% CI 0.58-0.99; p = 0.043) decreased esophageal cancer risk under the overdominant model without adjustment. We also found that rs3181052 had a negative effect on esophageal cancer under the overdominant model (OR = 0.72, 95% CI 0.53-0.97, p = 0.033) adjusted for age and gender. In stratified analyses by age >55 years, rs3181052 reduced the risk of esophageal cancer in the dominant and overdominant models. In addition, rs315919 had a remarkable influence on esophageal cancer risk in females, while the association was not significant between rs3181052 and esophageal cancer risk in males.

CONCLUSIONS

Our study provided the first evidence that IL1RN rs3181052, rs452204, and rs315919 are correlated with a decreased risk of esophageal cancer in a Northwest Han Chinese population. These findings may be useful for the development of early prognostics for esophageal cancer. However, further larger studies on different ethnic populations are warranted to verify these findings.