Interleukin-18 promoter polymorphisms and the disease progression of Hepatitis B virus-related liver disease

IL-18 and CD14 variants in chronic HBV predisposition: a case-control study with in silico analyses focused on transcription and splicing

Hepatitis B virus (HBV), a vaccine-avoidable infection, is a health concern worldwide, leading to liver disorders such as acute self-constraint and chronic hepatitis, liver failure, hepatic cirrhosis, and even hepatocellular carcinoma if untreated. 'Immunogeneticprofiling', genetic variations of the pro- and anti-inflammatory cytokines responsible for regulating the immune responses, cause person-to-person differences and impact the clinical manifestation of the disease. The current experimental-bioinformatics research was conducted to examine whether promoteric IL-18-rs187238 C > G and -rs1946518 T > G and intronic CD14-rs2569190 A > G variations are associated with chronic HBV. A total of 400 individuals (200 in each case and control group) participated in the study and were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The data was also assessed bioinformatics-wise for conservation, genomic transcription and splicing, and protein interactions. Findings proposed that unlike the IL-18-rs1946518 T > G and CD14-rs2569190 A > G, the IL-18-rs187238 C > G is a protector against chronic HBV (odds ratio [OR] = 0.62, 95% confidence intervals [CI]: 0.46-0.83, and p = 0.002). The TG/CC/AA, TG/CC/AG, TT/CC/AG, and GG/CC/AA combined genotypes significantly increased chronic HBV risk (p < 0.05), while the IL-18 G/T and G/G haplotypes lessened it (p < 0.05). Moreover, IL-18-rs1946518 T > G is in the protected genomic regions across mammalian species. In contrast to the IL-18-rs1946518 T > G, IL-18-rs187238 C > G is likely to create novel binding sites for transcription factors, and the CD14-rs2569190 A > G presumably changed the ribonucleic acid splicing pattern. More research on larger populations and other ethnicities is required to authenticate these results.

Comparison and Correlation of Genetic Variability of the HBV Pre-S Region in HIV/HBV Co-Infected Patients: Quasispecies Perspective

Background

Human immunodeficiency virus (HIV)/hepatitis B virus (HBV) co-infection can accelerate HBV-induced liver disease. A previous study showed that variation in the HBV pre-S region and quasispecies heterogeneity (Sn, mean genetic distance, dS, dN, and dS/dN) are both related to HBV-induced terminal liver disease in HBV mono-infection. Currently, data are lacking on quasispecies variation of the HBV pre-S region in HIV/HBV co-infection. Investigating the quasispecies variation of the HBV pre-S region and its related factors in HIV/HBV co-infection will help to better explore the pathogenic mechanism of HIV/HBV co-infection.

Methods

According to the HIV antibody results obtained before treatment, chronic HBV-infected patients were divided into HIV/HBV co-infected and HBV mono-infected groups. The clinical characteristics of all patients were collected, and DNA was extracted from the serum. The HBV pre-S region was amplified by nested PCR and was further TA cloned. BioEdit software 7.0 was used for sequence alignment with reference to the standard sequence of the matched HBV genotype. We used 1:1 propensity score matching (PSM) to control for baseline confounding factors between the two groups.

Results

After 1:1 PSM, we identified 100 patients with similar propensities: 50 HIV/HBV co-infected patients and 50 HBV mono-infected patients. HBV quasispecies indices were lower in the HIV/HBV co-infected group than those in the HBV mono-infected group. A significant correlation was observed between all quasispecies indices and soluble cluster of differentiation 163 (sCD163) and interleukin-18 (IL-18) in the HIV/HBV co-infected group; however, this phenomenon was not found in the HBV mono-infected group.

Conclusion

Combined HIV infection reduces quasispecies heterogeneity in the HBV pre-S region, and the quasispecies heterogeneity is related to the sCD163 and IL-18 levels.

A comprehensive evaluation of single nucleotide polymorphisms associated with hepatocellular carcinoma risk in Asian populations: A systematic review and network meta-analysis

BACKGROUND

Single nucleotide polymorphisms (SNPs) have been inconsistently associated with hepatocellular carcinoma (HCC) risk. This meta-analysis aimed to synthesize relevant data on SNPs associated with HCC in the Asian population.

METHODS

Databases were searched to identify association studies of SNPs and HCC in Asians published through January 2019. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated based on 41 studies (13,167 patients with HCC and 15,886 noncancer controls). Network meta-analysis and Thakkinstian's algorithm were used to select the most appropriate genetic model, along with false positive report probability (FPRP) for noteworthy associations.

RESULTS

Eleven SNPs meeting the inclusion criteria were tested for association with HCC, including CCND1 rs9344, PTGS2 rs689466, IL18 rs187238 and rs1946518, KIF1B rs17401966, MDM2 rs2279744, MIR146A rs2910164, MIR149 rs2292832, MIR196A2 rs11614913, MIR499A rs3746444, and TGFB1 rs1800469. A significant increase for HCC risk was observed for MDM2 rs2279744, and the dominant (pooled OR = 1.59, 95% CI: 1.26-2.00) and codominant (pooled OR = 1.37, 95% CI: 1.18-1.60) models were determined to be the most appropriate models. MIR499A rs3746444 also showed a significant association with HCC risk under the allele contrast model (pooled OR = 1.36, 95% CI: 1.05-1.77). Only the significance of MDM2 rs2279744 was noteworthy (FPRP < 0.2).

CONCLUSIONS

MDM2 rs2279744 is associated with HCC susceptibility in Asians, and the dominant and codominant models are likely the most appropriate models to estimate HCC risk.

Associations between twelve common gene polymorphisms and susceptibility to hepatocellular carcinoma: evidence from a meta-analysis

Background

Associations between polymorphisms in vitamin D receptor (VDR)/vascular endothelial growth factor (VEGF)/interleukin-18 (IL-18)/mannose-binding lectin (MBL) and susceptibility to hepatocellular carcinoma (HCC) were already explored by many studies, yet the results of these studies were inconsistent. The aim of this meta-analysis was to better clarify associations between polymorphisms in VDR/VEGF/IL-18/MBL and HCC by combing the results of all relevant studies.

Methods

Eligible publications were searched from PubMed, Embase, WOS, and CNKI. We used Review Manager to combine the results of individual studies.

Results

Thirty studies were included in this study. Combined results revealed that VDR rs7975232, VDR rs2228570, VEGF rs699947, VEGF rs3025039, IL-18 rs1946518, and MBL rs7096206 polymorphisms were all significantly associated with HCC in the overall pooled population. We also obtained similar significant associations for VDR rs7975232, VDR rs2228570, IL-18 rs1946518, and MBL rs7096206 polymorphisms in Asians.

Conclusions

Collectively, this meta-analysis proved that VDR rs7975232, VDR rs2228570, VEGF rs699947, VEGF rs3025039, IL-18 rs1946518, and MBL rs7096206 polymorphisms may confer susceptibility to HCC in certain populations.

IL-18 polymorphisms (-137C/G and -607A/C) are not associated with tuberculosis

Many studies have demonstrated that (IL-18) polymorphisms (including -137C/G and -607A/C) are correlated with the risk of tuberculosis. However, the meaning of this finding remains a matter of debate. In this study, electronic databases, including PubMed, EMBASE, Web of Science, Google Scholar and CNKI, were systemically queried to identify relevant studies. Subsequently, odds ratios and corresponding 95% confidence intervals were analysed. Our data indicated that the IL-18 -137C/G polymorphism was not related to tuberculosis susceptibility (GG vs. AA odds ratio = 0.71, 95% confidence interval 0.43–1.17; GA vs. AA: odds ratio =0.80, 95% confidence interval 0.57–1.13; dominant model: odds ratio = 0.78, 95% confidence interval 0.56–1.08; recessive model: odds ratio = 0.76, 95% confidence interval 0.46–1.25). Similarly, there was no association between the IL-18 -607A/C polymorphism and tuberculosis susceptibility (AA vs. CC: odds ratio = 1.25, 95% confidence interval 0.87–1.79; CA vs. CC: odds ratio = 1.10, 95% confidence interval 0.93–1.29; dominant model: odds ratio = 1.13, 95% confidence interval 0.90–1.41; recessive model: odds ratios=1.17, 95% confidence interval 0.90–1.53). No association was found in the subgroup analysis based on the Hardy–Weinberg equilibrium. In addition, there was no publication bias. The two IL-18 gene polymorphisms (-137C/G and -607A/C) were not markedly correlated with tuberculosis susceptibility. Well-designed studies with more subjects will be required for further validation of these results.

IL-18 and IL-1β Gene Polymorphisms: The Plausible Risk Factors for Chronic Hepatitis B

Chronic inflammation is the main risk factor for induction of liver cirrhosis and also hepatocellular carcinoma in chronic hepatitis B (CHB) patients. Although our knowledge is growing regarding molecular mechanisms of immune responses against viruses, the main mechanisms that lead to the progression of chronic inflammation and then CHB are yet to be clarified. IL-18 and IL-1β are the members of the IL-1 family and produced in the cytoplasm of a wide range of immune and nonimmune cells and activated by inflammasome pathways. The cytokines play key roles in the pathologies of CHB. IL-18 and IL-1β productions are altered in CHB patients. It has been hypothesized that the polymorphisms within IL-18 and IL-1β genes may be the main reasons for the induction of chronic inflammation in CHB patients. This review article discusses the related investigations regarding the main correlation between the polymorphisms within IL-18 and IL-1β genes and CHB pathogenesis.

The imbalance of peripheral interleukin-18 and transforming growth factor-β1 levels in patients with cirrhosis and esophageal varices

INTRODUCTION

The presence of esophageal varices in liver cirrhosis indicates clinically significant portal hypertension (PH), that results from structural and dynamic changes in the liver and systemic circulation including the activation of several fibrotic and inflammatory pathways. We assessed if interleukin-18 (IL-18) and transforming growth factor-β1 (TGF-β1) serum levels can be used as PH markers and reflect its severity.

MATERIAL AND METHODS

IL-18 and TGF-β1 peripheral blood levels were analyzed in 83 cirrhotic patients with esophageal varices compared to healthy individuals, in relation to MELD and Child-Pugh scores, laboratory and Doppler ultrasound parameters, and non-selective beta-blocker therapy (NSBB).

RESULTS

IL-18 concentration was significantly higher in cirrhotic patients, while TGF-β1 concentration was lower than in controls. MELD score correlated positively with IL-18 levels and negatively with TGF-β1 levels. IL-18 levels correlated positively with bilirubin, INR, ALT and AST levels, and negatively with albumin levels and erythrocyte count. TGF-β1 levels correlated positively with platelet count, leukocyte, and erythrocyte count, and negatively with bilirubin levels and prothrombin time. Moreover, significant correlations were found: between IL and 18 levels and portal, mesenteric superior, and splenic vein velocity, and between TGF-β1 levels and splenic vein diameter and spleen size. In a subgroup of patients, IL-18 levels significantly decreased after NSBB.

CONCLUSION

The observed imbalance of peripheral IL-18 and TGF-β1 levels indicates clinically significant PH associated with the presence of esophageal varices in cirrhosis. The correlation of IL-18 levels with liver failure indicators and decrease with NSBB suggest an important role of IL-18 in disease progression and its potential use as noninvasive test for PH assessment.

Systematic Review and Meta-Analysis on the Association between Polymorphisms in Genes of IL-12 Signaling Pathway and Hepatocellular Carcinoma Risk

We performed an updated meta-analysis and systematic review to explore the associations between polymorphisms in genes of IL-12 signaling pathway and hepatocellular carcinoma (HCC) risk. Diverse databases were retrieved to identify entire available studies, and odds ratios (ORs) correspondence with 95% confidence intervals (CIs) were performed to assess their associations. Finally, 6 polymorphisms in five genes of the IL-12 signaling pathway were extracted from 39 case-control studies, 26 publications. We identified that STAT4-rs7574865 polymorphism was significantly associated with an increased risk of HCC in allelic contrast, dominant, homozygote and recessive models. However, we failed to uncover any significant association between other polymorphisms in genes of IL-12 signaling pathway and HCC risk, including IL18-rs1946518 and -rs187238, IFN-γ-rs2430561, IL12A-rs568408, IL12B-rs3212227 and STAT4-rs7574865. When the subgroup analysis was conducted based on Hardy-Weinberg Equilibrium (HWE) status, we identified that IFN-γ-rs2430561 polymorphism was significantly associated with an increased risk of HCC in homozygote and recessive models of these studies whose control groups were conformed to HWE. To sum up, our study suggests that STAT4-rs7574865 is a risk factor for HCC. Further well-designed large sample size studies are warranted to shed new light on these findings.

Association of genetic variants in the interleukin-18 gene promoter with risk of hepatocellular carcinoma and metastasis in patients with hepatitis C virus infection

Hepatocellular carcinoma (HCC) is a primary malignancy of the liver, characterized by high vascularization and rapid tumor progression. The current case-control study aimed to analyze the influence of -607C/A and -137G/C polymorphisms in the interleukin-18 (IL-18) promoter on the risk of HCC occurrence and metastasis in Egyptian patients infected with hepatitis C virus (HCV). Both genetic variations were genotyped in 279 subjects including HCV patients with and without HCC and unrelated healthy subjects, using the allele-specific polymerase chain reaction (AS-PCR) method. The relationship between clinico-laboratory parameters including serum level of alpha-fetoprotein (AFP) and these polymorphisms was evaluated in HCC patients. The IL-18-607A allele and AA genotype were significantly related to a higher risk of developing HCC when comparing patients with HCC and controls, and were significantly related to a higher risk of metastasis when comparing metastatic and nonmetastatic groups in the Egyptian patients. In contrast, the IL18-137C allele and GC genotype were significantly related to a lower risk of developing HCC when comparing patients with HCC and controls, and HCV patients with and without HCC. A significant association was found between multinodular HCC and IL-18-607AA genotype, while, uninodular HCC was significantly associated with IL-18-137GG genotype. In addition, IL18-607AA and -137GG genotypes showed significant association with higher level of serum AFP. The detection of polymorphisms in the IL-18 promoter, in a combination with an evaluation of level of serum AFP, could be used as a molecular biomarker in the early diagnosis of HCC, which would aid the early management of the disease, thus decreasing the rate of mortality of this disease. © 2018 IUBMB Life, 70(2):165-174, 2018.

IL-18 polymorphisms contribute to hepatitis B virus-related cirrhosis and hepatocellular carcinoma susceptibility in Chinese population: a case-control study

IL-18 polymorphisms influence the transcriptional activity of the IL-18 gene and associated with various diseases. However, their relationships with hepatitis B virus-related liver diseases had not reached a consensus. So we conducted this case-control study with a view to clarifying the association. We included four groups: healthy controls, chronic hepatitis B virus (CHB) carriers, liver cirrhosis (LC) and hepatocellular carcinoma (HCC) groups with each group of 250 persons. Odd ratios (ORs) and 95% confidence intervals (95%CIs) with or without adjustment were calculated. Haplotype analysis was also performed. The results showed people carrying rs187238 CG genotype had a lower risk of LC (CG vs. CC: OR = 0.59, 95%CI = 0.38–0.91, P = 0.02), while GG genotype carriers had a higher risk of HCC (GG vs. CC+CG: OR = 4.73, 95%CI = 1.01–22.1, P = 0.03) than those with CC and CG genotypes in healthy group. Rs187238 GG genotype increased the risk from CHB to LC status (GG vs. CC: OR = 4.81, 95%CI = 1.03–22.6; GG vs. CC+CG: OR = 4.73, 95%CI = 1.01–22.1), meanwhile the trend also existed by controlling confounding factors (GG vs. CC: OR = 6.25, 95%CI = 1.09–35.8; GG vs. CC+CG: OR = 5.91, 95%CI = 1.04–33.7). Haplotype Crs187238Trs1946518 moderately decreased the risk of CHB carriers developing into HCC (OR = 0.69, 95%CI = 0.50–0.96, P = 0.03) after adjustment. In conclusion, IL-18 rs187238 GG genotype may increase the risk of HCC in healthy population and the risk of LC in CHB carriers.

Genetic polymorphisms -137 (rs187238) and -607 (rs1946518) in the interleukin-18 promoter may not be associated with development of hepatocellular carcinoma

This study meta-analyzed the literature on possible association of polymorphisms -137 (rs187238) and -607 (rs1946518) in the interleukin-18 (IL-18) promoter with risk of hepatocellular carcinoma (HCC). The analysis included 8 case-control studies on the -137 polymorphism (1,318 cases, 2,254 controls) and 7 case-control studies on the -607 polymorphism (1,262 cases, 1,696 controls). None of the five genetic models suggested a significant association between the -137 polymorphism and HCC risk: allelic model, OR 0.99, 95% CI 0.74-1.34, P = 0.97; recessive model, OR 0.98, 95% CI 0.65-1.46, P = 0.91; dominant model, OR 1.35, 95% CI 0.73-2.52, P = 0.34; homozygous model, OR 0.99, 95% CI 0.65-1.49, P = 0.95; heterozygous model, OR 0.99, 95% CI 0.66-1.48, P = 0.94. Similar results were obtained in subgroup analyses of Asian patients, Chinese patients, or patients with hepatitis B virus (HBV)-related HCC. Similar results were also obtained for the -607 polymorphism across the entire study population as well as in the three subgroups. The available evidence suggests no significant association of the -137 or -607 polymorphisms with risk of HCC in general or specifically of HBV-related HCC. These conclusions should be verified in large, well-designed studies.

Role of IL-18 Gene Promoter Polymorphisms, Serum IL-18 Levels, and Risk of Hepatitis B Virus-related Liver Disease in the Guangxi Zhuang Population: a Retrospective Case-Control Study

BACKGROUND

The aim of this study was to assess the relationship between IL-18 gene polymorphisms and HBV-related diseases and whether these polymorphisms influence its expression in the Guangxi Zhuang population.

MATERIALS AND METHODS

We enrolled 129 chronic HBV infected (CHB) patients, 86 HBV-related liver cirrhosis (LC) patients and 160 healthy controls in our study. Polymerase chain reaction-restriction fragment length polymorphism methods were used to detect IL-18 gene -607C/A, -137G/C polymorphisms, and an ELISA kit was employed to determine serum IL-18 levels.

RESULTS

No correlation was found between the -607C/A polymorphism and risk of HBV-related disease. For the -137G/C polymorphism, the GC genotype and C allele were associated with a significantly lower risk of CHB (95%CI: 0.32-0.95, p=0.034 and 95%CI: 0.35-0.91, p=0.018) and HBV-related LC (95%CI: 0.24-0.89, p=0.022 and 95%CI: 0.28-0.90, p=0.021). A similar decreased risk was also found with the A-607C-137 haplotype. With respect to IL-18 expression, it was significantly lower in both patient groups, but no association was noted between the two polymorphisms in the IL-18 gene and its expression.

CONCLUSIONS

Our study indicated that the -137C allele in the IL-18 gene may be a protective factor for HBV-related disease, and serum IL-18 level may be inversely associated with CHB and HBV-related LC.

IL18 Gene Variants Influence the Susceptibility to Chagas Disease

Chagas disease is a parasitic disorder caused by the infection with the flagellated protozoan Trypanosoma cruzi. According to the World Health Organization, more than six million people are currently infected in endemic regions. Genetic factors have been proposed to influence predisposition to infection and development of severe clinical phenotypes like chronic Chagas cardiomyopathy (CCC). Interleukin 18 (IL18) encodes a proinflammatory cytokine that has been proposed to be involved in controlling T. cruzi infection. In this study, we analyzed the possible role of six IL18 gene variants (rs5744258, rs360722, rs2043055, rs187238, rs1946518 and rs360719), which cover most of the variation within the locus, in the susceptibility to infection by T. cruzi and/or CCC. In total, 1,171 individuals from a Colombian region endemic for Chagas disease, classified as seronegative (n = 595), seropositive asymptomatic (n = 175) and CCC (n = 401), were genotyped using TaqMan probes. Significant associations with T. cruzi infection were observed when comparing seronegative and seropositive individuals for rs187238 (P = 2.18E-03, OR = 0.77), rs360719 (P = 1.49E-03, OR = 0.76), rs2043055 (P = 2.52E-03, OR = 1.29), and rs1946518 (P = 0.0162, OR = 1.22). However, dependence analyses suggested that the association was mainly driven by the polymorphism rs360719. This variant is located within the promoter region of the IL18 gene, and it has been described that it creates a binding site for the transcription factor OCT-1 affecting IL-18 expression levels. In addition, no evidence of association was observed between any of the analyzed IL18 gene polymorphisms and the development of CCC. In summary, our data suggest that genetic variation within the promoter region of IL18 is directly involved in the susceptibility to infection by T. cruzi, which provides novel insight into disease pathophysiology and adds new perspectives to achieve a more effective disease control.

Association between Interleukin-18 Polymorphisms and Hepatocellular Carcinoma Occurrence and Clinical Progression

We investigated the association between interleukin-18 (IL-18) polymorphisms and the susceptibility and clinicopathological state of hepatocellular carcinoma (HCC). In total, 901 participants, including 559 healthy controls and 342 patients with HCC, were recruited. The allelic discrimination of -607A/C (rs1946518) and -137G/C (rs187238) polymorphisms of IL-18 was assessed through real-time polymerase chain reaction by performing the TaqMan assay. The IL-18 -137G/C polymorphism but not the -607A/C polymorphism showed a significant association with the risk of HCC. Participants carrying the IL-18 -137 polymorphism with heterozygous G/C and homozygous CC genotypes showed a 1.987-fold increase (95% CI = 1.301-3.032; p = 0.001) in the risk of HCC compared with those homozygous for wild-type G/G. The 342 patients with HCC carrying the IL-18 -137G/C polymorphism were positive for hepatitis B virus (HBV) infection with an adjusted odds ratio of 1.668. Moreover, the 142 HBV positive patients with HCC and the IL-18 -137 polymorphism were positive for at least one C genotype and showed significant vascular invasion (p = 0.018). Furthermore, the level of α-fetoprotein was high in the patients carrying the IL-18 -137 polymorphism with GC+CC alleles (p = 0.011). In conclusion, the IL-18 -137G/C polymorphism with a GC+CC genotype could be a factor that increases the risk of HCC. Furthermore, the correlation between the IL-18 -137G/C polymorphism and HCC-related HBV infection is a risk factor for vascular invasion and has a synergistic effect that can further enhance HCC prognosis.

Association between IL-18 polymorphisms, serum levels, and HBV-related hepatocellular carcinoma in a Chinese population: a retrospective case-control study

BACKGROUND

Interleukin (IL)-18 gene polymorphisms have been found to play multiple roles in various diseases. However, studies focused on its involvement in hepatocellular carcinoma (HCC) remains controversial, and no much study has taken IL-18 serum levels into consideration. This study investigates the association between IL-18 polymorphisms and risk of hepatitis B virus-related HCC and their impact on serum IL-18 serum levels.

METHODS

A total of 153 patients and 165 healthy controls were enrolled in this study. Polymorphisms at positions -607C/A and -137G/C in the IL-18 gene were determined using the polymerase chain reaction-restriction fragment length polymorphism method. Serum IL-18 levels were determined with an ELISA kit.

RESULTS

No relationship was found between the -607C/A polymorphism and an individual's susceptibility to HCC. For the -137G/C polymorphism, the GC genotype and C allele were found to be significantly associated with decreased HCC risk (OR 0.506, 95% CI 0.290-0.882, P = 0.016 and OR 0.520, 95% CI 0.332-0.814, P = 0.004, respectively). The A(-607)C(-137) haplotype was also associated with a significant decreased risk of HCC (OR 0.495, 95% CI 0.294-0.834, P = 0.007). Serum IL-18 levels were found to be significantly lower in HCC patients compared to the control group in both the overall population and subjects with the different SNPs. Further, no association was found between serum IL-18 levels and the different genotypes within the same SNP.

CONCLUSION

These findings suggest that the -137G/C SNP in IL-18 may be a protective factor against HCC. Nevertheless, none of the studied SNPs was associated with the expression of IL-18.

IL-18, TNF, and IFN-γ alleles and genotypes are associated with susceptibility to chronic hepatitis B infection and severity of liver injury

This study evaluated the association of polymorphisms in the IL-18 (-607C/A and -137C/G), IFNγ (+874 A/T), and TNF (-238 A/G and -308 A/G) genes with susceptibility to HBV infection and severity of liver injury. A total of 259 chronic HBV-infected patients followed at the University Hospital, Faculty of Medicine of Ribeirão Preto, São Paulo, Brazil, and 202 healthy individuals were studied. Four Single Nucleotide Polymorphisms (SNPs) were amplified by Polymerase Chain Reaction (PCR). Liver biopsy was performed in 212 HBV-infected patients and classified according to severity of liver fibrosis (scores 0-4) and necroinflammatory activity (HAI scores 0-18). TNF-308*A allele (P < 0.001; OR = 2.16) and TNF -308 AA genotype (P = 0.026; OR = 5.43) were associated with susceptibility to HBV infection. An association was found between severe liver fibrosis when compared to mild fibrosis and the following polymorphisms: Alleles IL-18 -137*G (P = 0.004; OR = 3.45), TNF -308*A (P < 0.001; OR = 3.39), and IFNγ +874*T (P = 0.029; OR = 1.85) and IL-18 -137 GG genotype (P = 0.009; OR = 3.70). No significant association was found between IL-18 (-607 A/C) polymorphism and severity of liver fibrosis. Alleles IL-18 -137*G (P = 0.028; OR = 2.64) and TNF-308*A (P = 0.002; OR = 3.06) and IL-18 -137 GG genotype (P = 0.011; OR = 4.20) were associated with severe necroinflammatory activity (HAI>12) when compared to mild necroinflammatory activity (HAI 1-8). The results suggest that IL-18 -137C/G, TNF-308 G/A and IFNγ +874 A/T SNPs were associated to more severe liver injury in chronic HBV infection. TNF -308*A allele and TNF -308 AA genotype could play a role in the susceptibility to HBV infection.

Association of IL-18 promoter gene polymorphisms with rheumatoid arthritis: a meta-analysis

Interleukin-18(IL-18) plays a potential pathological role in rheumatoid arthritis (RA). The conclusions of the published reports on the relationship between single-nucleotide polymorphisms -607C/A (rs1946518) and -137G/C (rs187238) located in the IL-18 gene promoter and RA risk remain controversial. This meta-analysis was performed to evaluate the association between IL-18 gene promoter (-607A/C and -137C/G) polymorphisms and RA using (1) allele, (2) codominant, (3) dominant, and (4) recessive models. Literature search was conducted up to January, 2013, in PubMed, EMBASE, Spring-link, Web of Science, Wanfang (Chinese) and China National Knowledge Infrastructure (CNKI). A total of 10 studies from eight articles involving 2,662 cases and 2,168 controls for -607A/C polymorphism and 9 studies from six articles involving 1,331 cases and 1,468 controls for -137C/G polymorphism were considered in the meta-analysis. For the relationship of IL-18 -607A/C polymorphism with RA risk, significant association was observed in allele model (OR = 0.778, 95 % CI = 0.633-0.955) and dominant model (OR = 0.618, 95 % CI = 0.466-0.819). However, no significant association could be observed between -137C/G polymorphism and RA risk under all genetic models (allele model: OR = 0.940, 95 % CI = 0.777-1.138; codominant model: OR = 1.079, 95 % CI = 0.574-2.029; dominant model: OR = 0.913, 95 % CI = 0.779-1.069; recessive model: OR = 1.133, 95 % CI = 0.586-2.190). In the subgroup analysis by ethnicity, significant result was also found in Asian populations but not found in Caucasian populations for the relationship of IL-18 -607A/C polymorphism with RA risk; while no obvious association was found between IL-18 -137C/G polymorphism and RA risk. This meta-analysis indicates that IL-18 -607A/C polymorphism in promoter region may be associated with RA risk.

Relationship between cytokine gene polymorphisms and chronic hepatitis B virus infection

Hepatitis B virus (HBV) infection is still a public health problem worldwide, being endemic in some parts of the world. It can lead to serious liver diseases such as chronic hepatitis, cirrhosis, and hepatocellular cancer. The differences in host immune response can be one of the reasons for the various clinical presentations of HBV infection. Polymorphisms of genes encoding the proinflammatory and antiinflammatory cytokines, which are responsible for regulation of the immune response, can affect the clinical presentation of the infection. Particularly, the polymorphisms of the genes encoding cytokines such as interleukin (IL)-1, IL-6, IL-8, IL-10, IL-18, IL-28B, interferon-γ, tumor necrosis factor-α, tumor growth factor-β1, and regulatory molecules like vitamin D receptor and chemokine receptor 5 can be responsible for different clinical presentations of HBV infections. The genomic information about cytokines and other mediators can be important for determining high-risk people for developing chronic hepatitis or hepatocellular cancer and may be used to plan treatment and preventive approaches for these people. In this review, the current knowledge in the literature on the association between cytokine/regulatory molecule gene polymorphisms and clinical course of chronic HBV infection is summarized, and the clinical implementations and future prospects regarding this knowledge are discussed.

Association of polymorphisms in interleukin-18 and interleukin-28B genes with outcomes of hepatitis B virus infections: a meta-analysis

Several polymorphisms in the interleukin-18 (IL-18) and nterleukin-28B (IL-28B) genes have been reported to influence hepatitis B virus (HBV) infection. However, the published findings have been conflicting. We conducted meta-analyses of randomized, controlled trials to address the association of IL-18 or IL-28B polymorphisms and the outcomes of HBV infection. Weipu, Wanfang, CNKI, MEDLINE, PubMed, EMBASE, and Cochrane Library databases were employed to search for citations using the MeSH terms as "interleukin-18"/"interleukin-28B" AND "HBV" AND "gene" AND "polymorphism" without any restriction in language and publication year. Meta-analysis was conducted by RevMan 5.0 software. The results showed that the IL28B rs8099917 AA genotype (AA vs AC + CC: odds ratio (OR) = 0.63, 95 % confidence interval (CI) = 0.46-0.87) was associated with a decreased risk of hepatocellular carcinoma (HCC). Carriage of IL28B rs12979860 CC genotype was associated with an increased risk for developing liver cirrhosis among patients with HBV infection (CC vs CT + TT: OR = 1.39, 95 % CI = 1.04-1.85). Further well-designed large studies are warranted to confirm the mechanisms by which these are involved in these outcomes of HBV infection.

Association analysis between SNPs in IL-28B gene and the progress of hepatitis B infection in Han Chinese

OBJECTIVE

As a candidate gene association study, we investigated the genetic association of SNPs in IL-28B genes with different outcomes of HBV infection, including LC and HCC occurrence.

METHODS

Chinese Han subjects were categorized into two groups: 406 LC caused by CHB and 406 HCC caused by CHB. Genomic DNA was isolated from whole blood samples, SNPs were detected using high resolution melting curve (HRM) method. PCR amplification was carried out under the same conditions in a 96-well plate in Real-Time PCR System. Then 341 LC and 356 HCC patients caused by HBV infection were analyzed as a verification by independent sample. 393 CHB patients and 244 health subjects were included as control.

RESULTS

CHB patients who progress to LC or HCC showed a significant different frequency in rs12979860 (p = 0.046). Patients with HCC carried more frequently the T alleles in rs12979860 comparison to LC. Same results were found in the independent sample.

CONCLUSION

IL-28B rs12979860 C/T polymorphism T allele appears to be more prevalent in patients with HCC than in LC. Carriage of this allele seems to enhance the risk for developing HCC. Gene polymorphism of IL-28B may confer symptomatic specificity in progress and extent of hepatitis B infection.

Interleukin-18 and interferon-gamma polymorphisms are implicated on proviral load and susceptibility to human T-lymphotropic virus type 1 infection

Interleukin-18 (IL-18) and interferon-gamma (IFN-γ) exert important functions in both innate and adaptive immune responses against intracellular pathogens and viruses. Previous studies suggested that host genetic factors, including cytokines gene polymorphisms, could be involved in the pathogenesis of human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Thus, we analyzed -137C/G and -607A/C of the IL-18 promoter and +874T/A of the IFN-γ in DNA samples from 98 HTLV-1-infected individuals exhibiting or not clinical symptoms and 150 healthy control individuals. The IL-18 promoter -607CC genotype was significantly lower in HTLV-1 asymptomatic carriers (HAC) and HTLV-1-infected individuals (HAC + HAM/TSP) than healthy control group. In contrast, the -607AC genotype was significantly higher in HAC and HTLV-1-infected individuals group compared to the healthy control group. The -137G/-607A IL-18 haplotype was higher in infected group than healthy control group, and the -137C/-607C IL-18 haplotype was increased in the healthy control group compared to the others. Finally, the IFN-γ polymorphism analysis showed that the HTLV-1-infected individuals with +874AT genotype presented higher proviral load than +874AA genotype. These data indicate that the IL-18-607AC genotype and -137G/-607A haplotype could be a risk factor for HTLV-1 infection, whereas the protective effect could be conferred by -607CC genotype and -137C/-607C haplotype. Also, the IFN-γ could be implicated on the proviral load levels.

Relationship between interleukin 18 polymorphisms and susceptibility to chronic hepatitis B virus infection

AIM

To identify the relationship between the tagging single nucleotide polymorphism sites (tagSNPs) of the Interleukin-18 (IL-18) gene and genetic susceptibility to chronic hepatitis B virus infection in Chinese patients.

METHODS

Five hundred and one cases of chronic hepatitis B virus (HBV) infection and 301 HBV natural clearance controls were studied. Two tagSNPs in the IL-18 gene (rs1946518A/C and rs574424C/G) were genotyped by the Multiplex Snapshot technique. The genotype and allele frequencies were calculated and analyzed.

RESULTS

In the genotypes of rs1946518, the AA type was present at a higher frequency in the patients compared to those in the controls. Odds ratio (OR) of the AA genotype for the comparison with that of the AC and the CC genotype was 1.537 (95% confidence intervals (CI): 1.116-2.218, P = 0.009 < 0.025). In phenotypes, the allele C at rs1946518 was of a significantly lower frequency in the patients with chronic hepatitis B than that in the controls (P = 0.017 < 0.025). OR of the allele A for the comparison with that of the allele C was 1.279 (95% CI: 1.045-1.567). As for the rs574424 genotypes, no significant difference in this genotype distribution or in this allele frequency between the patients and the control subjects was observed. No significant difference in the haplotype frequencies between the patients with chronic hepatitis B and HBV natural clearance individuals was displayed.

CONCLUSION

The data suggest that genotype AA and the allele A of the IL-18 at position rs1946518 are closely associated with the resistance to chronic hepatitis B and may be the dangerous gene. However, no statistical association was found between polymorphisms of rs574424 for IL-18 and hepatitis B.

Carriage of the EGF rs4444903 A>G functional polymorphism associates with disease progression in chronic HBV infection

Because epidermal growth factor (EGF) up-regulation is characteristic of the cirrhotic liver, we hypothesised that the EGF rs4444903 A > G functional polymorphism might be associated with a worse disease course in patients with chronic HBV infection. To verify this hypothesis, 170 HBV-positive patients (125 males) with a median age of 52 years were studied. Sixty-two of these patients were followed longitudinally for a median time of 21 years. Genotyping for the EGF rs4444903 A > G polymorphism was performed by the polymerase chain reaction-based restriction fragment length polymorphism assay. In the cross-sectional study, the EGF rs4444903 A > G polymorphism genotypic frequencies significantly differed between transplant patients (A/A = 20·4%, A/G = 52·3%, G/G = 27·3%) and HBsAg+ carriers (active and inactive: A/A = 35·7%, A/G = 47·6%, G/G = 16·7%, P = 0·036 for the linear trend). In the longitudinal study, the EGF rs4444903 A > G polymorphism was found to be an independent predictor of cirrhosis development (O.R. 7·73, 95% C.I. 1·21-49·5, P = 0·007). Three groups of patients were identified: A/A female homozygotes (n = 9), A/A male homozygotes (n = 13) and carriers of the G allele of either gender (n = 40). Cirrhosis did not occur among A/A females (n = 0/9), seldom occurred among A/A males (n = 2/13) and reached the highest frequency among G/* patients (n = 13/40, P = 0·026). In conclusion, the EGF rs4444903 A > G polymorphism appears to be associated with an unfavourable disease course of chronic HBV infection and cirrhosis development. This effect might be modulated, at least in part, by the gender of the patient.

Lack of association of -607 C/A and -137 G/C polymorphisms in interleukin 18 gene with susceptibility to gout disease in Chinese Han male population

To identify association of IL18-607 C/A and -137 G/C polymorphism with susceptibility to gout in Chinese Han male population, We evaluate the genetic contribution of the IL18-607 C/A and -137 G/C polymorphism in 202 gout male patients and 493 gout-free control of Chinese Han population by allele-specific polymerase chain reaction assay. Our results reveal no significant association between the polymorphisms -607C/A and -137G/C in IL18 with gout. Our study might suggest that -607 C/A and -137 G/C polymorphisms in the promoter of IL18 are not associated with susceptibility to gout and thus do not play a major role in the development of gout in the Chinese Han male population.