Genetic polymorphisms in the cytokine genes and risk of hepatocellular carcinoma in low-risk non-Asians of USA

Association of IL-6 G-174C (rs1800795) variant with the susceptibility to hepatocellular carcinoma in patients with chronic hepatitis

AIM

An ineffective immune response resulting from dysregulation of cytokine production might encourage viral persistence and cause chronic viral hepatitis to worsen. This study examined the relationship between alterations in interleukin-6 (IL-6) levels and the IL-6 - 174 G > C (rs1800795) polymorphism, as well as how this polymorphism affects the development and progression of chronic hepatitis brought on by hepatitis B (HBV) and hepatitis C (HCV) into hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

Whole blood samples from 126 Egyptian patients with HCC (111 with HCV and 15 with HBV), as well as 126 age- and sex-matched healthy individuals, were used to extract DNA. Using PCR-based allele-specific amplification (ASA), the existence of the IL-6 G-174C polymorphism was investigated. Additionally, each participant's serum IL-6 levels were determined using an enzyme-linked immunosorbent assay (ELISA).

RESULTS

The primary observations revealed that HCC patients had greater serum levels of IL-6 compared to the control groups (p < 0.001). Patients with the variant (CG and GG) genotype in the HCC group were found to have more disease severity indicated by higher levels of alpha-fetoprotein (AFP) and a higher ascites grade, as well as increased inflammatory activity as defined by higher levels of IL-6 and C-reactive protein (CRP) (p < 0.001 for both) in comparison to patients with the wild-type (CC) genotype (p < 0.001 and p = 0.002, respectively).

CONCLUSION

The rs1800795 SNP in the IL-6 gene was associated with increased inflammatory activity and high levels of IL-6, indicating that this SNP may play a role in the development of HCC in Egyptian patients with chronic viral hepatitis.

Disparity of Hepatocellular Carcinoma in Tumor Microenvironment-Related Genes and Infiltrating Immune Cells between Asian and Non-Asian Populations

Hepatocellular carcinoma (HCC) is the most common cause of primary liver cancer deaths worldwide. The major risk factors for liver cancer development are cirrhosis, hepatitis B virus (HBV), hepatitis C virus (HCV) infection, and chronic alcohol abuse. HCC displays heterogeneity in terms of biology, etiology, and epidemiology. In Southeast Asia and Africa, chronic HBV infection is a major risk factor for HCC, whereas chronic HCV infection is a risk factor for HCC in western countries and Japan. Environmental and genetic conditions also play a role in the regional and temporal variations in the incidence of HCC. In this study, we used the ESTIMATE (ESTIMATE, Estimation of stromal and immune cells in malignant tumor tissues using expression data) algorithm and the CIBERSOFT tool to analyze gene expression profiles and infiltrating immune cells in HCC between Asian and non-Asian patients. The results showed that stromal and immune scores were dependent on overall survival (OS) in non-Asian patients but not in Asian patients. Kaplan-Meier survival analysis revealed four differentially expressed genes (DEGs) that were significantly associated with OS in non-Asian patients only. CIBERSORT (CIBERSORT, Cell type identification by estimating relative subsets of known RNA transcripts) analysis indicated that the composition of infiltrating immune cells was significantly different between Asian and non-Asian patients. By parsing the subclasses of HCC, the ability to predict prognosis and guide therapeutic targets for potentially actionable HCC may be improved.

Statistical meta-analysis to investigate the association between the Interleukin-6 (IL-6) gene polymorphisms and cancer risk

A good number of genome-wide association studies (GWAS), including meta-analyses, reported that single nucleotide polymorphisms (SNPs) of the IL-6 gene are significantly associated with various types of cancer risks, though some other studies reported insignificant association with cancers, in the literature. These contradictory results may be due to variations in sample sizes and/or deficiency of statistical modeling. Therefore, an attempt is made to provide a more comprehensive understanding of the association between the IL-6 gene SNPs (rs1800795, rs1800796, rs1800797) and different cancer risks, giving the weight on a large sample size, including different cancer types and appropriate statistical modeling with the meta-dataset. In order to attain a more reliable consensus decision about the association between the IL-6 gene polymorphisms and different cancer risks, in this study, we performed a multi-case statistical meta-analysis based on the collected information of 118 GWAS studies comprising of 50053 cases and 65204 control samples. Results from this Meta-analysis indicated a significant association (p-value < 0.05) of the IL-6 gene rs1800796 polymorphism with an overall increased cancer risk. The subgroup analysis data based on cancer types exhibited significant association (p-value < 0.05) of the rs1800795 polymorphism with an overall increased risk of cervical, liver and prostate cancers; the rs1800796 polymorphism with lung, prostate and stomach cancers; and the rs1800797 polymorphism with cervical cancer. The subgroup analysis of ethnicity data showed a significant association (p-value < 0.05) of an overall cancer risk with the rs1800795 polymorphism for the African and Asian populations, the rs1800796 polymorphism for the Asian only and the rs1800797 polymorphism in the African population. Comparative discussion showed that our multi-case meta-analyses received more support than any previously reported individual meta-analysis about the association between the IL-6 gene polymorphisms and cancer risks. Results from this study, more confidently showed that the IL-6 gene SNPs (rs1800795, rs1800796 and rs1800797) in humans are associated with increased cancer risks. Therefore, these three polymorphisms of the IL-6 gene have the potential to be evaluated as a population based rapid, low-cost PCR prognostic biomarkers for different types of cancers diagnosis and research.

Association between interleukin 6 polymorphisms (rs1800796, rs1800795, rs2069837, rs17147230, and rs1800797) and hepatocellular carcinoma susceptibility: a meta-analysis

Aim of the study

We reported the association between interleukin 6 polymorphisms (rs1800796, rs1800795, rs2069837, rs17147230, and rs1800797) and hepatocellular carcinoma (HCC) susceptibility in a meta-analysis.

Material and methods

The studies were retrieved by searching the search terms in Scopus, PubMed, Web of Science, and Cochrane Library databases until June 2020. The analyses were done by RevMan 5.3 software using odds ratios (ORs) and 95% confidence intervals (CIs) and the analysis of publication bias and sensitivity analyses were performed by CMA 2.0 software.

Results

Searching through the databases, 316 records were retrieved and finally 13 studies were analyzed in the present meta-analysis. For the rs1800797 polymorphism, there was an elevated risk of AA genotype (OR = 2.68, p = 0.03) in HCC patients compared to healthy controls. Also, there was an elevated risk of AA (OR = 3.06, p = 0.04) and GA (OR = 2.61, p = 0.005) genotypes in HCC patients compared to liver cirrhosis patients. For rs2069837 polymorphism, there was an elevated risk of GG genotype (OR = 2.25, p = 0.01) in HCC patients compared to healthy controls. For rs17147230, T allele (OR = 1.31, p = 0.03) and TT genotype (OR = 1.83, p = 0.02) had elevated risks in HCC patients compared to healthy controls.

Conclusions

The present meta-analysis confirmed that there was an elevated risk of the AA and GA genotypes of rs1800797 polymorphism and the GG genotype of rs2069837, and the T allele and TT genotype of rs17147230 in HCC.

Association of interleukin-6 gene polymorphisms with the risk of hepatocellular carcinoma: An up-to-date meta-analysis

BACKGROUND

This study was aimed to evaluate the association between interleukin-6 (IL-6) gene polymorphisms and the risk of hepatocellular carcinoma (HCC) in a meta-analysis.

METHODS

A literature search was performed for case-control studies published during May, 1993 to May, 2020 focusing on IL-6 gene polymorphisms (-174G > C, -572G > C, and -597G > A) and HCC susceptibility by using PubMed, Cochrane Database, EMBASE, Web of science, and China National Knowledge Infrastructure. From 128 full-text articles, 11 were included in this meta-analysis. I index was used to assess heterogeneity and Newcastle-Ottawa Scale was utilized for quality assessment.

RESULTS

For IL-6 -174G > C polymorphism, in codominant (GG vs CC: odds ratios [OR] = 2.78, 95% confidence intervals [CI] = 1.25-6.19, P = .01, I = 16%) and recessive (GG+GC vs CC: OR = 2.76, 95% CI = 1.29-5.90, P = .009, I = 3%) models, IL-6 -174G>C polymorphism was significantly associated with the risk of HCC. In dominant (GG vs CC+GC: OR = 1.80, 95% CI = 0.92-3.54, P = .09, I = 86%) and allele (G vs C: OR = 1.49, 95% CI = 0.95-2.32, P = .08, I = 68%) models, IL-6 -174G>C polymorphism had no impact on the risk of HCC. However, in non-Italian Caucasian population, IL-6 -174G>C polymorphism was significantly related to the occurrence of HCC in both dominant (GG vs CC+GC: OR = 3.26, 95% CI = 2.29-4.65, P < .00001, I = 0%) and allele (G vs C: OR = 2.48, 95% CI = 1.48-4.15, P = .0006) models. Such correlations also could be observed when healthy individuals were selected as controls. For IL-6 -572G>C and -597G>A polymorphisms, no significant association was observed in all models, regardless of the source of control and population subgroups. No publication bias could be calculated when Begg and Egger tests were employed.

CONCLUSION

This meta-analysis indicated that IL-6 -174G>C polymorphism was significantly related with the risk for HCC, especially in non-Italian Caucasian population. No significant association was observed for the correlation between IL-6 -572G>C and -597G>A polymorphisms and HCC susceptibility.

Associations between hepatocellular carcinoma risk and rs3212227 and rs568408 polymorphisms: a systematic review and meta-analysis

Background

Interleukin-12 (IL-12) is considered to be a risk factor for cancer; however, its role in hepatocellular carcinoma (HCC) remains unknown. This study aimed to explore the impacts of the IL-12 rs3212227 and rs568408 gene polymorphisms on HCC.

Methods

We searched PubMed, Embase, Web of Science, and Chinese Knowledge Infrastructure databases for studies on the associations between HCC and IL-12 rs568408 and rs3212227 polymorphisms published prior to 1 May 2020. The effects of the polymorphisms on HCC susceptibility were presented as odds ratios (ORs) and associated 95% confidence intervals.

Results

Seven studies were ultimately included, including 2375 cases and 3445 controls. The rs3212227 polymorphism was significantly associated with the risk of HCC in both the dominant model (CC+AC vs. AA, OR=1.22) and the allele model (C vs. A, OR=1.12). Combined analysis of rs568408 yielded a significant relative risk for HCC in the dominant (AA+AG vs. GG, OR=1.13), recessive (AA vs. AG+GG, OR=1.72), allele (A vs. G, OR=1.29), heterozygote (AG vs. GG, OR=1.27), and homozygote models (AA vs. GG, OR 1.17).

Conclusion

The IL-12 rs3212227 and rs568408 gene polymorphisms are associated with an increased risk of HCC.

Association between the Interleukin-10 -1082 G/A polymorphism and risk of hepatocellular carcinoma

BACKGROUND

Inconsistent results have been reported from studies investigating the relationship of the interleukin-10 (IL-10) -1082 G/A polymorphism and the susceptibility of hepatocellular carcinoma (HCC). Therefore, a thorough literature review of relatedstudies was performed in this meta-analysis to examine the association of the interleukin-10(IL-10) -1082 G/A polymorphism with HCC susceptibility.

METHODS

Electronic databases were searched for literature on the relationship between interleukin-10(IL-10) -1082 G/A polymorphism and the risk of HCC in accordance with the inclusion and exclusion criteria. The selected studies were analyzed using the Stata 12.0 software. Finally, the strength of the associations was evaluated using the odds ratio (OR) and 95% confidence intervals (95% CI).

RESULTS

A total of six case-control studies were enrolled into the current meta-analysis, which included a total of 911 patients and 1889 control subjects. Our data revealed no association between the IL-10 -1082 G/A polymorphism and the risk of HCC (GG vs AA:OR=0.84, 95%CI=0.57-1.25; AG vs AA:OR=0.85, 95%CI=0.70-1.05; Dominant model: OR=0.85, 95%CI=0.70-1.03; and Recessive model: OR=0.92, 95%CI = 0.64-1.32). Similarly, no association was found in sub-group analysis based on ethnicity.

CONCLUSION

The results of our study suggest no association between IL-10 -1082 G/A polymorphism and the risk of HCC.

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.

A single nucleotide polymorphism of the interferon-γ gene and susceptibility to hepatitis B virus-related cirrhosis: a randomized controlled trial

OBJECTIVE

This study aimed to explore the correlation between a single nucleotide polymorphism (SNP) of the interferon-γ (IFN-γ) gene and susceptibility to hepatitis B virus (HBV) -related cirrhosis in the Chinese population.

METHOD

PCR-LDR was employed for the genotyping of two SNPs, rs1861494 and rs2069718, of the IFN-γ gene in 230 patients with HBV-related cirrhosis and 320 inactive HBsAg carriers without cirrhosis. It was then determined whether the Hardy-Weinberg (H-W) equilibrium was satisfied. The odds ratio (OR) and 95% confidence interval (CI) were analyzed using the chi-square test and univariate non-conditional logistic regression. Haplotypes were established using SHEsis and SNPStats online software and their interaction with non-genetic factors was analyzed.

RESULTS

Compared with the AA genotype of rs1861494 SNP, AG+GG genotypes increased the risk of HBV-related cirrhosis. There was a significant difference in the distribution of A and G alleles between the case group and the control group (P<0.05). There was also a significant difference in the distribution of AA, AG, GG, AA, and AG+GG genotypes and A/G alleles between the case group and the control group (P<0.05). This indicated that the G allele may be a risk factor for HBV-related cirrhosis. By analyzing the different distribution of haplotypes in the case group and the control group, we observed significant differences in the distribution of AA, AG and GA haplotypes between the case and control groups (P<0.05). Haplotypes of the IFN-γ gene did not interact with other relevant factors.

CONCLUSION

The G allele of rs1861494 SNP as well as AG and GG genotypes and G allele of rs2069718 SNP may be risk factors of HBV-related cirrhosis. The AA haplotype may be a protective factor for HBV-related cirrhosis, while the AG haplotype is a risk factor for HBV-related cirrhosis.

Associations of interleukin-6 gene polymorphisms with cancer risk: Evidence based on 49,408 cancer cases and 61,790 controls

Many molecular epidemiologic studies have shown that interleukin-6 (IL-6) polymorphisms are significantly associated with susceptibility for various cancers. However, the conclusions of these studies are inconsistent. The purpose of the present study was to explore the association between three common IL-6 loci (rs1800795, rs1800796, and rs1800797) and the risk for various cancers. We systematically searched the PubMed, Web of Science, Wanfang and China national knowledge infrastructure (CNKI) databases for relevant publications and obtained 108 eligible studies, involving 49,408 cancer patients and 61,790 cancer-free controls. Odds ratio (OR), 95% confidence interval (CI), and false positive reporting probability (FPRP) were used to evaluate cancer risk. All statistical analyses were performed using the R software meta package. We observed a non-significant association between rs1800795 and overall cancer risk, while rs1800797 was found to have a false positive association with overall risk of cancer. Subgroup analyses of rs1800797 also suggested non-significant association and rs1800795 played a protective role in liver cancer. Rs1800796 was found to be associated with overall cancer risk, particularly in Asian patients and those with prostate cancer. These findings provide evidence that IL-6 polymorphisms may affect cancer risk.

Role of interleukin-12 gene polymorphisms in the onset risk of cancer: a meta-analysis

Many molecular epidemiologic studies have explored the possible links between interleukin-12 (IL-12) polymorphisms and various cancers. However, results from these studies remain inconsistent. This meta-analysis is aimed to shed light on the associations between three common loci (rs568408, rs2243115, rs3212227) of IL-12 gene and overall cancer risk. Our meta-analysis finally included 33 studies comprising 10,587 cancer cases and 12,040 cancer-free controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the cancer risk. We observed a significant association between IL-12B rs3212227 and overall cancer risk, especially in hepatocellular carcinoma, nasopharyngeal cancer, and among Asians. IL-12A polymorphisms (rs2243115 and rs568408) were found no influence on overall cancer risk. Nevertheless, stratification analyses demonstrated that rs568408 polymorphism contributed to increasing cancer risk of Caucasians and cervical cancer. And, rs2243115 may enhance the risk of brain tumor. These findings provided evidence that IL-12 polymorphisms may play a potential role in cancer risk.

Genetic polymorphisms of IL-6 promoter in cancer susceptibility and prognosis: a meta-analysis

IL-6 is critical for tumorigenesis. However, previous studies on the association of IL-6 promoter polymorphisms with predisposition to different cancer types are somewhat contradictory. Therefore, we performed this meta-analysis regarding the relationship between IL-6 promoter single nucleotide polymorphisms and cancer susceptibility and prognosis. Up to April 2017, 97 original publications were identified covering three IL-6 promoter SNPs. Our results showed statistically significant association between IL-6 promoter and cancer risk and prognosis. Subgroup analysis indicated that rs1800795 was significantly associated with increased risk of cervical cancer, colorectal cancer, breast cancer, prostate cancer, lung cancer, glioma, non-Hodgkin’s lymphoma and Hodgkin’s lymphoma but not gastric cancer and multiple myeloma. Furthermore, rs1800796 was significantly associated with increased risk of lung cancer, prostate cancer and colorectal cancer but not gastric cancer. Additionally, rs1800797 was significantly association with breast cancer, non-Hodgkin’s lymphoma, B-cell lymphoma and diffuse large B-cell lymphoma but not gastric cancer. Simultaneously, rs1800795 and rs1800796 were associated with a significantly higher risk of cancer in Asia and Caucasian, rs1800797 was associated with a significantly risk of cancer in Caucasian but not in Asia. Furthermore, IL-6 promoter polymorphisms were significantly associated with the prognosis of cancer. Considering these promising results, IL-6 promoter including rs1800795, rs1800796 and rs1800797 may be a tumor marker for cancer therapy.

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.

Aberrant expression of B7‑H4 may contribute to the development of hepatocellular carcinoma

In order to determine the effect of B7‑H4 on the development of human hepatocellular carcinoma (HCC), the expression levels of B7‑H4 were evaluated using reverse transcription‑polymerase chain reaction and flow cytometry in HL‑7702 and Huh7 cells. B7‑H4 protein expression levels were analyzed using western blotting and immunohistochemistry in HCC tissues collected from patients and from a mouse tumor model. Soluble B7‑H4 (sB7‑H4), interferon‑γ (IFN‑γ), and interleukin‑4 (IL‑4) in blood serum were assessed using ELISA in patients with HCC and mice injected with tumor cells. B7‑H4 was expressed in HCC cell lines, mouse tumor tissues and HCC patient tissues. However, B7‑H4 was not detected in HL‑7702 cells or normal human liver tissues. The expression level of B7‑H4 was positively correlated with tumor‑node‑metastasis (TNM) stage, lymph node metastasis, and differentiation degree in patients with HCC. sB7‑H4 levels in blood serum samples collected from patients with HCC and tumorigenic mice were higher compared with healthy controls. Expression levels of IFN‑γ were reduced, and IL‑4 levels were increased in blood serum samples of patients with HCC and tumorigenic mice compared with healthy controls. sB7‑H4 expression levels were negatively correlated with IFN‑γ levels, and with the ratio of IFN‑γ to IL‑4. Additionally, sB7‑H4 was positively correlated with IL‑4 levels in mouse tumor tissues, serum samples obtained from tumorigenic mice and human HCC patients. Notably, the levels of sB7‑H4 and IL‑4 were positively correlated and IFN‑γ was negatively correlated with the TNM stage of patients with HCC. In addition, sB7‑H4 and IL‑4 expression levels increased and levels of IFN‑γ and the ratio of IFN‑γ/IL‑4 decreased as a function of time post tumor implantation in the mouse model. The present study determined that aberrant expression of B7‑H4 contributed to HCC development. B7‑H4 may be a potential target for therapy and diagnosis of HCC.

Hepatitis-related hepatocellular carcinoma: Insights into cytokine gene polymorphisms

Hepatocellular carcinoma (HCC) is a primary liver cancer, which is one of the most prevalent cancers among humans. Many factors are involved in the liver carcinogenesis as lifestyle and environmental factors. Hepatitis virus infections are now recognized as the chief etiology of HCC; however, the precise mechanism is still enigmatic till now. The inflammation triggered by the cytokine-mediated immune response, was reported to be the closest factor of HCC development. Cytokines are immunoregulatory proteins produced by immune cells, functioning as orchestrators of the immune response. Genes of cytokines and their receptors are known to be polymorphic, which give rise to variations in their genes. These variations have a great impact on the expression levels of the secreted cytokines. Therefore, cytokine gene polymorphisms are involved in the molecular mechanisms of several diseases. This piece of work aims to shed much light on the role of cytokine gene polymorphisms as genetic host factor in hepatitis related HCC.

The association of three promoter polymorphisms in interleukin-10 gene with the risk for colorectal cancer and hepatocellular carcinoma: A meta-analysis

Mounting evidence supports a potent inhibitory role of interleukin-10 (IL-10) in tumor carcinogenesis, angiogenesis and metastasis. This meta-analysis was designed to examine the association of three promoter polymorphisms (−592C > A, −819C > T and −1082G > A) in IL-10 gene with the risk for colorectal cancer and hepatocellular carcinoma. Qualification assessment and data collection were completed by two authors independently. The random-effects model using the DerSimonian and Laird method was fitted by the STATA software. Twenty-five articles involving 5933 cases and 9724 controls were meta-analyzed. Overall comparisons of the mutant alleles (−592A, −819T and −1082A) of three promoter polymorphisms with alternative wild alleles failed to reveal any statistical significance for both colorectal cancer and hepatocellular carcinoma (P > 0.05), and the likelihood of heterogeneity was low (I² < 50%). For −592C > A polymorphism, a significant risk for colorectal cancer was identified when analysis was restricted to East Asians (odds ratio or OR = 1.41, 95% confidence interval or CI: 1.18–1.68, P < 0.001) and retrospective studies (OR = 1.23, 95% CI: 1.09–1.39, P = 0.001). As weighed by the Egger’s test and the fill-and-trim method, there was a low probability of publication bias for all studied polymorphisms. Our findings collectively suggest that the −592C > A polymorphism in IL-10 gene might be a susceptibility locus for colorectal cancer in East Asians.

Tumor Necrosis Factor-α-308 G/A Polymorphisms and Risk of Hepatocellular Carcinoma: A Meta-Analysis

CONTEXT

Hepatocellular carcinoma (HCC) is a common disorder throughout the world that can develop due to various factors, including genetics. Tumor necrosis factor-α (TNF-α) is the most frequently studied cytokine related to the risk of developing HCC, and an association between the 308 position of the TNF-α promoter (TNF-α-308) and HCC risk has been confirmed in various reports.

EVIDENCE ACQUISITION

The PubMed, Scopus, and Google Scholar databases were searched through July 12, 2015, for studies on associations between TNF-α-308 and the risk of HCC. To determine this association, odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

A total of 23 case-control studies were investigated, involving 3,389 cases and 4,235 controls. The overall conclusion was that the A allele was more frequent in case groups compared to control groups (13.4% vs. 8.4%). Thus, the A allele was significantly associated with increased HCC risk (OR = 1.77; 95% CI = [1.26-2.50]; P value < 0.002). In addition to the allelic model, the dominant model (AA + AG vs. GG) was significantly associated with HCC risk (OR = 1.80; CI = [1.29-2.51]; P value < 0.001). In the sensitivity analysis for co-dominant (AA vs. GG) and recessive models (AA vs. AG + GG), no trustworthy associations with the risk of HCC development were observed.

CONCLUSIONS

This meta-analysis indicated that the TNF-α-308 G/A polymorphism is significantly associated with increased susceptibility to HCC. However, to confirm this finding, more studies are needed on TNF-α-308 G/A polymorphisms associated with HCC.

A Causal Role of Genetically Elevated Circulating Interleukin-10 in the Development of Digestive Cancers: Evidence from Mendelian Randomization Analysis Based on 29,307 Subjects

Recent studies have observed a high level of circulating interleukin-10 (IL-10) in patients with digestive cancers, yet whether elevated IL-10 is causally associated with digestive cancers so far remained unresolved. We therefore meta-analyzed available observational studies with Mendelian randomization method to explore this causal association by employing IL-10 gene 3 variants (-592C>A, -819C>T, and -1082A>G) as instruments. Data were available from 52 articles encompassing 29,307 subjects. Subgroup analysis by cancer type indicated that -1082A>G was associated with increased risk of gastric cancer (odds ratio [OR] = 1.19; 95% confidence interval [CI]: 1.05-1.35; P = 0.006), and the association was reinforced for intestinal type gastric cancer (OR = 1.26; 95%CI: 1.09-1.44; P = 0.001). By ethnicity, risk estimate for -1082G allele carriers was increased by 21% for digestive cancers in East Asians (95%CI: 1.05-1.40; P = 0.009). As for the genotype-phenotype association, carriers of -1082G allele had an overall 20.21 pg/mL higher IL-10 level than those with -1082AA genotype (P = 0.023). In further Mendelian randomization analysis, the predicted OR for 10 pg/mL increment in IL-10 was 1.14 (95%CI: 1.01-16.99) in gastric cancer. Our findings provided evidence for a causal role of genetically elevated IL-10 in the development of gastric cancer, especially in East Asians and for intestinal type gastric cancer.

The association of TNF-308 (G/A) gene polymorphisms and hepatocellular carcinoma risk: a meta-analysis

Objective

Many studies have examined the association between the TNF-308 G/A polymorphism gene polymorphisms and hepatocellular carcinoma risk in various populations, but their results have been inconsistent. To assess this relationship more precisely, a meta-analysis was performed.

Methods

The PubMed and CNKI (China National Knowledge Infrastructure) database was searched for case-control studies. Odds ratios (OR) with 95% CIs were used to determine the strength of association between the TNF-308 G/A polymorphisms and HCC risk. The pooled ORs for the risk associated with the TNF-308 G/A genotype, the A carriers (A/G + A/A) vs. the wild-type homozygotes (G/G), A/A vs. G/G were calculated, respectively. Subgroup analyses were done by ethnicity and smoking status. Heterogeneity assumptions were assessed by chi-square-based Q-test.

Results

Ultimately, 21 studies, comprising 2,923 hepatocellular carcinoma cases and 4,323 controls were included. Overall, the A carriers (G/A + A/A) vs. the wild-type homozygotes (G/G), the pooled OR was 1.05 (95% CI, 0.93-1.19; P=0.000 for heterogeneity), for A/A vs. G/G the pooled OR was 1.07 (95% CI, 0.95-1.21; P=0.007 for heterogeneity). In the stratified analysis by ethnicity, the significantly risks were found among non-Asians. However, for Asians, significantly risks were not found.

Conclusions

The TNF-308 G/A polymorphisms are not associated with hepatocellular carcinoma risk among Asians, but for non-Asians.

IL-6 Plays a Crucial Role in HBV Infection

Interleukin-6 (IL-6), a cytokine mainly produced by activated monocytes, has broad pleiotropic actions that affect the functions of a variety of lymphoid cells. The roles of IL-6 in regulating immunity to infections are currently being defined. Remarkably, IL-6-mediated cellular and humoral immune responses play a crucial role in determining the outcome of viral infection. This article reviews the current knowledge on the critical role of IL-6 in hepatitis B virus (HBV) infection. As a competent intermediary, IL-6 derived from activated monocytes plays an important role in promoting lymphocytes responses that are essential for effective viral control. However, as a mediator of inflammation, IL-6 is also involved in the development of HBV-induced liver cirrhosis and exacerbating liver injury. Overall, the current data point to IL-6 as an immunoregulatory cytokine in HBV infection. Immunotherapeutic strategies aimed at optimizing the beneficial effects of IL-6 in HBV infection may prove to be an ordeal in the future, as they should foster the strengths of IL-6 while circumventing potential drawbacks.

Genetic variants in IL12 influence both hepatitis B virus clearance and HBV-related hepatocellular carcinoma development in a Chinese male population

IL12 plays a major role not only in inducing appropriate immune responses against viral infections (including HBV) but also in the antitumor immune response. This study was conducted to investigate the relationships of genetic variants in IL12 with hepatitis B virus (HBV) clearance and development of HBV-related hepatocellular carcinoma (HCC). We genotyped three single nucleotide polymorphisms (SNPs) of the IL12A (rs568406 and rs2243115) and IL12B (rs3212227) in 395 HBV-positive HCC patients, 293 persistent HBV carriers and 686 subjects with HBV natural clearance from southern China, using the improved multiplex ligase detection reaction (iMLDR) method. Logistic regression analysis adjusted for age, smoking, and alcohol consumption status showed that rs568408 variant genotypes were significantly associated with host HBV-related HCC risk when compared with persistent HBV carriers, and carriers of the GA + AA genotype decreased the HCC risk in comparison with GG carriers (adjusted OR = 0.53, 95 % CI 0.35-0.80, P = 0.002). No relationships between the rs2243115 and rs3212227 SNPs and HCC risk were observed (all P > 0.05). Besides, rs568408 showed an approaching significant effect on susceptibility to HBV persistent infection (adjusted OR = 1.34, 95 % CI 0.99-1.81, P = 0.057 in dominant genetic models). Furthermore, the TG haplotype was observed to be associated with a significantly increased risk of HBV-related HCC (OR = 1.42, 95 % CI 1.10-1.83, P = 0.006), while TA haplotype was associated with a decreased risk of HBV-related HCC (OR = 0.61, 95 % CI 0.45-0.83, P = 0.002). Our results reveal that the IL12A rs568408 variant may be a marker SNP for risk of both HBV clearance and HBV-related HCC development.

Nine susceptibility loci for hepatitis B virus-related hepatocellular carcinoma identified by a pilot two-stage genome-wide association study

Previous studies have indicated that complex interactions among viral, environmental and genetic factors lead to hepatocellular carcinoma (HCC). To identify susceptibility alleles for hepatitis B virus (HBV)-related HCC, the present study conducted a pilot two-phase genome-wide association study (GWAS) in 660 Han Chinese individuals. In phase 1, a total of 500,447 single-nucleotide polymorphisms (SNPs) were genotyped in 50 HCC cases and 50 controls using Affymetrix GeneChip 500k Array Set. In phase 2, 1,152 SNPs were selected from phase 1 and genotyped in 282 cases and 278 controls using the Illumina GoldenGate platform. The prior probability of HCC in control subjects was assigned at 0.01, and false-positive report probability (FPRP) was utilized to evaluate the statistical significance. In phase 1, one SNP (rs2212522) showed a significant association with HCC (P_allele=5.23×10⁻⁸; OR_allele=4.96; 95% CI, 2.72–9.03). In phase 2, among 27 SNPs with unadjusted P_allele<0.05, 9 SNPs were associated with HCC based on FPRP criteria (FPRP <0.20). The strongest statistical evidence for an association signal was with rs2120243 (combined OR_allele=1.76; 95% CI, 1.39–2.22; P=2.00×10⁻⁶), which maps within the fourth intron of VEPH1. The second strongest statistical evidence for an association was identified for rs1350171 (combined OR_allele=1.66; 95% CI, 1.33–2.07; P=6.48×10⁻⁶), which maps to the region downstream of the FZD4 gene. The other potential susceptibility genes included PCDH9, PRMT6, LHX1, KIF2B and L3MBTL4. In conclusion, this pilot two-phase GWAS provides the evidence for the existence of common susceptibility loci for HCC. These genes involved various signaling pathways, including those associated with transforming growth factor β, insulin/phosphoinositide 3 kinase, Wnt and epidermal growth factor receptor. These associations must be replicated and validated in larger studies.

IL12RB2 Polymorphisms correlate with risk of lung adenocarcinoma

In a previous study, lack of IL-12 signaling in il12rb2 knock-out mice was found to predispose to lung adenocarcinoma (LAC). We asked whether specific polymorphisms of the human IL12RB2 gene may confer susceptibility to LAC. We studied IL12RB2 single nucleotide polymorphisms (SNPs) spanning from the promoter to the first untranslated exon of the gene. Genotypes of 49 individuals with LAC were compared with those of 93 healthy subjects. Two allele variants were found to be associated with increased susceptibility to LAC. One haplotype (hap), hap18, was more frequent in patients (18%) versus controls (6%) and significantly associated with increased probability of disease occurrence. Furthermore, IL-12 driven STAT4 phosphorylation in T cell blasts from healthy individuals was found to correlate with both single allele variants and haplotypes. In conclusion, genetically determined low signaling activity of IL-12R predisposes to the development of LAC.

Association Between IL-4 Polymorphisms and Risk of Liver Disease: An Updated Meta-Analysis

Interleukin-4 (IL-4) polymorphisms have been reported to influence an individual's susceptibility to liver disease as it is a central anti-inflammatory Th2 cytokine; however, these results remain controversial.A comprehensive meta-analysis of the relevant literature was thus performed to better estimate the relationship between IL-4 polymorphisms and liver disease.Systematic searches of various databases (PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure) for studies published before July 5, 2015 were performed. Odds ratios (ORs) with 95% confidence intervals (CIs) calculated in fixed or random-effects models were used to estimate the strength of the association. Subgroup analyses, meta-regression, Galbraith plots, and sensitivity analyses were also performed.A total of 16 case-control studies, of which 15 involved the -590C/T polymorphism and 3 involved the -33T/C polymorphism, were included in the study. With respect to the -590C/T polymorphism, a significantly increased risk of liver diseases was found in the overall population (TT + CT vs CC: OR = 1.25, 95% CI = 1.06-1.49, P = 0.009 and CT vs CC: OR = 1.22, 95% CI = 1.00-1.48, P = 0.048) and the Asian population (TT + CT vs CC: OR = 1.28, 95% CI = 1.04-1.57, P = 0.020). Further subgroup analyses also showed significant associations between the -590C > T polymorphism and the risk of hepatitis C infection and hepatocellular carcinoma. However, no association was found between the -33T/C polymorphism and risk of liver diseases in all comparison models.This meta-analysis suggested that the IL-4 -590C > T polymorphism is associated with an increased risk of hepatitis C infection and hepatocellular carcinoma, especially among the Asian population.

Circulating interleukin-6 and cancer: A meta-analysis using Mendelian randomization

Interleukin-6 (IL-6) plays a contributory role in the progression and severity of many forms of cancer; it however remains unclear whether the relevance between circulating IL-6 and cancer is causal. We therefore meta-analyzed published articles in this regard using IL-6 gene -174G/C variant as an instrument. Seventy-eight and six articles were eligible for the association of -174G/C variant with cancer and circulating IL-6, respectively. Overall analyses failed to identify any significance between -174G/C and cancer risk. In Asians, carriers of the -174CC genotype had an 1.95-fold increased cancer risk compared with the -174GG genotype carriers (P = 0.009). By cancer type, significance was only attained for liver cancer with the -174C allele conferring a reduced risk under allelic (odds ratio or OR = 0.74; P = 0.001), homozygous genotypic (OR = 0.59; P = 0.029) and dominant (OR = 0.67; P = 0.004) models. Carriers of the -174CC genotype (weighted mean difference or WMD = −4.23 pg/mL; P < 0.001) and -174C allele (WMD = −3.43 pg/mL; P < 0.001) had circulating IL-6 reduced significantly compared with the non-carriers. In further Mendelian randomization analysis, a reduction of 1 pg/mL in circulating IL-6 was significantly associated with an 12% reduced risk of liver cancer. Long-term genetically-reduced circulating IL-6 might be causally associated with a lower risk of liver cancer.

Th1/Th2 cytokines and their genotypes as predictors of hepatitis B virus related hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the predominant type of primary liver cancer, is one of the most serious life-threatening malignancies, worldwide. In majority of the cases, HCC develops after prolonged and persistent chronic liver disease. hepatitis B virus (HBV) or HCV infection is prominent etiological factors, attributing to this condition. It has been well documented that HBV, being the inducer of chronic inflammation, is the main causative agent in causing HCC, particularly in Asian countries. The HBV infection leads to a wide range of clinical symptoms from carrier state to malignancy. Cytokines being immune-modulatory molecules, are the key mediators in the defense mechanism against viral infection. In this regard, this review will detail the substantial role of key Th1: interleukin 1 (IL-1), IL-2, IL-12, tumor necrosis factor-α, interferon-γ; Th2: IL-4, IL-10 and non Th1/Th2: IL-6, transforming growth factor-β1 cytokines genotypes in analyzing the variability in the clinical manifestations in an HBV-afflicted individual, which might finally, culminates into HCC. Since cytokine production is regulated genetically, the cytokine promoter region single-nucleotide polymorphisms induced changes, greatly affects the cytokine production, thus resulting into differential outcome of immune balance.

Interferon-γ +874A/T polymorphism and hepatocellular carcinoma risk: a meta-analysis

BACKGROUND

Studies have evaluated the association between interferon-γ (IFN-γ) +874A/T polymorphism and hepatocellular carcinoma (HCC) risk, but the results are controversial. We performed this meta-analysis to further investigate this association.

MATERIAL AND METHODS

Relevant studies were searched by using the PubMed, Web of Science, and Embase databases. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the association. Subgroup analysis and sensitivity analysis were conducted.

RESULTS

Seven case-control studies (859 HCC patients and 1482 healthy controls) were identified to assess the association between IFN-γ +874A/T polymorphism and risk of HCC. IFN-γ +874A/T polymorphism was significantly associated with an increased risk of HCC (OR=1.38; 95% CI 1.12-1.70; P=0.002). In the subgroup analysis by ethnicity, IFN-γ +874A/T polymorphism was significantly associated with HCC risk in Asians (OR=1.42; 95% CI 1.08-1.87; P=0.01), but no significant association was found in Caucasians (OR=1.21; 95% CI 0.86-1.70; P=0.28). IFN-γ +874A/T polymorphism also increased HBV-induced HCC risk (OR=1.42; 95% CI 1.08-1.87; P=0.01). In the subgroup analysis by control source, IFN-γ +874A/T polymorphism was associated with HCC risk in hospital-based studies (OR=1.45; 95% CI 1.09-1.53; P=0.01). A marginal association was found in population-based studies (OR=1.33; 95% CI 0.97-1.83; P=0.08).

CONCLUSIONS

This meta-analysis indicates that the IFN-γ +874A/T polymorphism might contribute to HCC risk.

Interleukin-12B+1188A/C polymorphism contributes to increased hepatocellular carcinoma susceptibility: evidence from a meta-analysis

BACKGROUND

Interleukin-12 (IL-12) is a multifunctional cytokine that induces interferon (IFN)-γ secretion and plays an important role in antitumor immunity. The IL-12B +1188A/C polymorphism was found to correlate with a decreased cytokine production and/or activity, which may lead to increased susceptibility to cancers including hepatocellular carcinoma (HCC). Previous epidemiological studies investigating the association between IL-12B +1188A/C polymorphism and HCC risk reported inconsistent results. We performed a meta-analysis to derive a precise estimation of the association.

METHODS

All studies published up to July 2014 on the association between IL-12B +1188A/C polymorphism and HCC risk were identified by searching electronic databases including PubMed, Embase, Cochrane library, and Chinese Biomedical Literature database (CBM). Data were extracted by two independent authors and the odds ratios (ORs) together with corresponding 95% confidence intervals (CIs) were used to assess the association between IL-12B +1188A/C polymorphism and HCC risk.

RESULTS

Five studies with 1864 cases and 2077 controls were included in the meta-analysis. We observed that the IL-12B +1188A/C polymorphism was significantly correlated with increased HCC risk when all studies were pooled into the meta-analysis (CC vs. AA: OR=1.306, 95% CI 1.063-1.606, P=0.011; AC vs. AA: OR=1.193, 95% CI 1.014-1.405, P=0.034; CC+AC vs. AA: OR=1.260, 95% CI 1.098-1.445, P=0.001). In subgroup analyses by ethnicity, source of control, and study quality, significant increased HCC risk was found in Asians, hospital-based studies, and high quality studies.

CONCLUSIONS

The present meta-analysis suggests that the IL-12B+1188A/C polymorphism is a low-penetrant risk factor for HCC development, especially among Asians. Further large and well-designed studies are needed to confirm this association.

Role of IL-4 gene polymorphisms in HBV-related hepatocellular carcinoma in a Chinese population

Background

Interleukin-4 (IL-4) is best known as an important mediator and modulator of immune and inflammatory responses. Hepatocellular carcinoma (HCC) is a typical inflammation-related cancer, and genetic variations in the IL-4 gene may be associated with the risk of hepatitis B virus (HBV)-related HCC. However, few studies have been conducted on their association.

Objectives

To clarify the effects of IL-4 gene polymorphisms on the risk of HBV-related HCC, two common variants, −590C/T (rs2243250) and −33C/T (rs2070874), and their relationship with HBV-related disease risk were investigated in a Chinese population.

Methods

IL-4 −590C/T and −33C/T polymorphisms were examined in 154 patients with HBV-related HCC, 62 patients with HBV-induced liver cirrhosis (LC), 129 patients with chronic hepatitis B (CHB), and 94 healthy controls, using the polymerase chain reaction-restriction fragment length polymorphism method and DNA sequencing.

Results

Overall, no significant differences were observed regarding the IL-4 −590C/T and −33C/T polymorphism genotypes, alleles, or haplotypes between the patient groups and the healthy controls. However, the CC genotypes of IL-4 −590C/T and −33C/T polymorphisms were observed to be significantly associated with CHB in subgroup analysis in males [CC versus TT (OR: 4.193, 95% CI: 1.094–16.071, P = 0.037; and OR: 3.438, 95% CI: 1.032–11.458, P = 0.044) and CC versus TT+CT (OR: 4.09, 95% CI: 1.08–15.49, P = 0.038; and OR: 3.43, 95% CI: 1.04–11.28, P = 0.042)].

Conclusions

These findings suggest that genetic variants in IL-4 −590C/T and −33C/T polymorphisms may be a risk factor for CHB in Chinese males but not for HBV-related LC or HCC.

New Approaches for Studying Alcoholic Liver Disease

Alcoholic liver disease (ALD) is major cause of chronic liver injury which results in liver fibrosis and cirrhosis. According to the surveillance report published by the National Institute on Alcohol Abuse and Alcoholism, liver cirrhosis is the 12th leading cause of death in the United States with 48 % of these deaths being attributed to excessive alcohol consumption. ALD includes a spectrum of disorders from simple steatosis to steatohepatitis, fibrosis, and hepatocellular carcinoma. Several mechanisms play a critical role in the pathogenesis of ALD. These include ethanol-induced oxidative stress and depletion of glutathione, pathological methionine metabolism, increased gut permeability and release of endotoxins into the portal blood, recruitment and activation of inflammatory cells including bone marrow-derived and liver resident macrophages (Kupffer cells). Chronic alcohol consumption results in liver damage and activation of hepatic stellate cells (HSCs) and myofibroblasts, leading to liver fibrosis. Here we discuss the current view on factors that are specific for different stages of ALD and those that regulate its progression, including cytokines and chemokines, alcohol-responsive intracellular signaling pathways, and transcriptional factors. We also review recent studies demonstrating that alcohol-mediated changes can be regulated on an epigenetic level, including microRNAs. Finally, we discuss the reversibility of liver fibrosis and inactivation of HSCs as a potential strategy for treating alcohol-induced liver damage.

Aberrant expression of p-STAT3 in peripheral blood CD4+ and CD8+ T cells related to hepatocellular carcinoma development

Hepatocellular carcinoma (HCC) is one of the most common cancer types worldwide. The signal transducer and activator of transcription 3 (STAT3) protein is a member of the STAT transcription factor family. Oncogenesis, invasion, and metastasis of HCC are associated with activation of STAT3. However, whether aberrant expression of phosphorylated STAT3 (p-STAT3) in peripheral CD4+ and CD8+ T cells relates to HCC pathogenesis remains unclear. In this study, the expression of p-STAT3 in CD4+ and CD8+ T cells, and the levels of interferon-γ (IFN-γ), interleukin-4 (IL-4), IL-6 and IL-10 in the human hepatoma cell line Huh7 co-cultured with peripheral blood mononucleated cells (PBMCs) of healthy volunteers were measured. The correlations between p-STAT3 and IFN-γ/IL-4, IFN-γ, IL-4, IL-6 and IL-10 were then analyzed. Results showed that the p-STAT3 level is higher in CD4+ and CD8+ T cells in the peripheral blood of HCC patients, and in PBMCs co-cultured with Huh7 cells compared to controls. The cytokine (IL-4, IL-6 and IL-10) levels were increased and the IFN-γ level was decreased in the serum of HCC patients and in supernatants of PBMCs co-cultured with Huh7 cells. Correlation analyses demonstrated that the IFN-γ/IL-4 ratio and the IFN-γ level negatively correlate to the p-STAT3 level in CD4+ and CD8+ T cells in samples from patients and in cells cultured in vitro. By contrast, the levels of IL-4, IL-6 and IL-10 positively correlated to the p-STAT3 level. This study indicated that the expression of p-STAT3 is upregulated in peripheral CD4+ and CD8+ T cells of HCC patients, and which may result in abnormal immune surveillance and thereby, contribute to HCC pathogenesis.

The -1082A>G polymorphism in promoter region of interleukin-10 and risk of digestive cancer: a meta-analysis

The -1082A>G polymorphism is located in promoter region of interleukin-10 (IL-10) and it could affect the production of IL-10. Numerous studies have investigated the association between IL-10 -1082A>G and risk of digestive cancer. However, the conclusion is still inconsistent. Here, we have performed a meta-analysis and systematic review to determine the association between the IL-10 -1082A>G and susceptibility to digestive cancer. In this meta-analysis, we identified 40 eligible studies, involving 7195 patients of digestive cancer and 11755 controls. By pooling all eligible studies, we found the variant -1082G allele significantly increased risk of digestive cancer (G vs. A: OR = 1.181, 95% CI: 1.057-1.319). Further stratified analysis was performed to evaluate the influence of cancer types, ethnicities, study design, sample size and Hardy-Weinberg equilibrium. Stratified analysis suggested that, the -1082A>G polymorphism was only associated with increased risk for gastric cancer (G vs. A: OR = 1.281, 95% CI: 1.102-1.488) and in Asian population (G vs. A: OR = 1.399, 95% CI: 1.188-1.646). No significant publication bias was detected. Based on 40 studies and 18950 participants, we found the variant IL-10 -1082G allele significantly increased susceptibility to digestive cancer, especially for gastric cancer and in Asian population.

Study progress in immune escape mechanism and immunotherapy for primary hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common malignant tumor as well as a big threat to human health. The occurrence, development and prognosis of HCC are closely relevant to the immune escape and immune function in HCC patients. HCC patients, especially those in the terminal stage of the disease, have impaired immune function, which leads to reduced quality of life and raised death rate. Since immunotherapy can regulate the immune function to reduce recurrence and metastasis, improve the life quality and prolong survival, it has become an important part of comprehensive treatment for HCC. In this paper, we review the latest progress in research of immune escape mechanism and immunotherapy for primary HCC.

Susceptibility to hepatocellular carcinoma in the Chinese population--associations with interleukin-6 receptor polymorphism

Hepatocellular carcinoma (HCC) is one of the most deadly malignant diseases in the world. Genetic variations in cytokine genes may have an effect on the immune and inflammatory responses which are associated with HBV-HCC. The interleukin-6 (IL-6) receptor is known to be mainly expressed by hepatocytes, neutrophils, monocytes/macrophages, and some lymphocytes, which have been used as prognostic markers in a variety of inflammatory diseases such as rheumatoid arthritis, asthma, and Crohn's disease. To determine the association of IL-6 receptor (IL-6R) polymorphism with the risk of hepatocellular carcinoma (HCC) development in the Chinese population, a hospital based case-control study was designed consisting of 192 subjects with HCC and 192 healthy control subjects. Our results revealed no risk associations (p = 0.064) with rs6684439 CT genotypes. However, rs6684439 TT genotypes were associated with a significantly decreased risk of HBV-related HCC compared with the CC genotype (odds ratio (OR) = 0.469, 95 % confidence interval (CI) 0.228-0.967, p = 0.040). The data also revealed that subjects with the T allele appeared to have a lower susceptibility to HBV-related HCC than those with the C allele (OR = 0.657, 95 % CI 0.476-0.907, p = 0.011). The present study supports the view that variants in the rs6684439 SNP of IL-6R is associated with a lower risk of HBV-related HCC, and this could provide valuable clues to understanding the mechanisms underlying susceptibility to this malignant disease. Replication and further functional studies should be carried out in the future using larger samples.

TNF-α promoter polymorphisms and risk of recurrence in patients with squamous cell carcinomas of the nonoropharynx

Functional polymorphisms of tumor necrosis factor-alpha (TNF-α) may play a critical role in the regulation of immune and inflammatory responses and could affect transcriptional levels of the TNF-α gene and thus contribute to carcinogenesis and outcomes of cancer patients. In a cohort study, we explored the associations between TNF-α polymorphisms and risk of recurrence of squamous cell carcinoma of the nonoropharynx (SCCNOP). We used log-rank test and multivariable Cox models to evaluate the associations between TNF-α polymorphisms and risk of recurrence. In overall comparisons, patients with the TNF-α -857 CC, TNF-α -863 CC and TNF-α -1031 TT genotypes had significantly worse disease-free survival (log-rank, p = 0.014, log-rank, p = .020, and log-rank, p = .002, respectively) and higher risk of disease recurrence than patients with the corresponding variant genotypes, respectively (hazard ratio [HR], 1.4, 95% CI, 1.1-1.9, HR, 1.4, 95% CI, 1.0-1.8 and HR, 1.6, 95% CI, 1.2-2.2, respectively). However, no significant association was detected for the TNF-α -308 polymorphism. Moreover, in further stratified analyses based on smoking status and treatment, we found that the associations of the TNF-α -857, TNF-α -863 and TNF-α -1031 polymorphisms with risk of recurrence were more pronounced in smokers and patients treated with chemoradiation. Our findings support a significant role of the TNF-α -857, TNF-α -863 and TNF-α -1031 polymorphisms in recurrence of SCCNOP, especially in smokers and patients treated with chemoradiation. Future prospective studies with larger sample size are needed to confirm these findings.

TNF-α-308 polymorphism and risk of digestive system cancers: A meta-analysis

AIM: To evaluate the association between the tumour necrosis factor alpha-308 (TNF-α-308) gene polymorphism and the risk of digestive system cancers.

METHODS: All eligible case-control studies published up to December 2012 were identified by searching PubMed, Web of Science, Embase and China National Knowledge Internet without language restrictions. The risk of digestive system cancers associated with the TNF-α-308 polymorphism was estimated for each study using odds ratio (OR) together with its 95%CI, respectively. Cochrane Collaboration RevMan 5.1 was used to perform the analysis. A χ²-test-based Q statistic test and an I² test were performed to assess the between-study heterogeneity. When the Q test was significant (P < 0.05) or I² > 50%, the random effects model was used, otherwise the fixed effects model was used.

RESULTS: Fifty-eight studies from fifty-five publications with a total of 9986 cancer patients and 15511 healthy controls were included. Overall, a significant association was found between the TNF-α-308 polymorphism and the risk of digestive system cancers [dominant model: OR = 1.23, 95%CI: 1.09-1.39, (G/A) vs (G/G): OR = 1.15, 95%CI: 1.02-1.28, (A/A) vs (G/G): OR = 1.44, 95%CI: 1.19-1.73, recessive model: OR = 1.38, 95%CI: 1.15-1.66]. Furthermore, when the analysis was stratified by ethnicity, similar results were observed in both the Asian and Caucasian populations, except for the dominant model and heterozygote comparisons in the Asian population [dominant model: OR = 1.24, 95%CI: 0.99-1.56, (G/A) vs (G/G): OR = 1.09, 95%CI: 0.96-1.24]. When the cancer type subgroups were examined, similar results were detected in gastric and hepatocellular carcinomas; however, no significant association was observed among other digestive system cancers.

CONCLUSION: The TNF-α-308 gene polymorphism may be significantly associated with the risk of gastric and hepatocellular carcinomas, but not colorectal, pancreatic, or oesophageal cancer, in the Asian population.

Effect of IL-12B, IL-2, TGF-β1, and IL-4 polymorphism and expression on hepatitis B progression

The hepatitis B virus (HBV) infection-induced chronic inflammation is considered to be the major etiological factor for HBV-related disease chronicity. Cytokines act as the key coordinators of the inflammatory responses involved in HBV disease pathogenesis. The present study assessed association among IL-12B(+1188), IL-2(-330), TGF-β1(-509), and IL-4(-590) genotypes; mRNA; and protein levels with HBV-hepatocellular carcinoma (HCC) risk in India. For this, 403 subjects (153 controls, 67 inactive HBV-carriers, 62 chronic-active HBV patients, 62 HBV-cirrhotics, and 59 HBV-HCC ssubjects) were enrolled in the study. The genotyping was carried by polymerase chain reaction (PCR)-restriction fragment length polymorphism (IL-12+1188A/C, IL-2-330T/G, and TGF-β1-509C/T), and allele specific (AS)-polymerase chain reaction (IL-4-590C/T). Enzyme-linked immunosorbent assay and reverse transcriptase-polymerase chain reaction methods were used for assessing protein and the mRNA expression, respectively, of the mentioned cytokines. The study revealed that the IL-12B(+1188) CC genotype shared a significant positive association with hepatitis, among controls. While, in the case of IL-2(-330), both the TG and GG genotypes were not significantly associated with HCC risk. The TGF-β1(-509) TT genotype acted as a potential protective factor for cirrhosis and the HCC risk, among carriers. On the contrary, the IL-4(-590) CT genotype was found to be a vital protective factor for the development of hepatitis, among carriers. Besides, IL-12B, TGF-β1, and IL-2 seem to be majorly involved in the development of HCC, while, IL-4 might be responsible for the progression of the HBV disease till cirrhosis development. These initial findings are indicative of the vital role of genotypes and/or levels of IL-12B, IL-2, IL-4, and TGF-β1 in HBV disease chronicity in Indian population.

Association of interleukin-12 polymorphisms and serum IL-12p40 levels with osteosarcoma risk

No previous studies reported the association of IL-12 polymorphisms with osteosarcoma. We aimed to investigate the association in a Chinese population. IL-12A rs568408, rs2243115, and IL-12B rs3212227 polymorphisms were evaluated in a case-control study of 106 osteosarcoma patients and 210 health controls by using polymerase chain reaction-restriction fragment length polymorphism. Serum IL-12p40 levels were measured by enzyme-linked immunosorbent assay. The serum IL-12p40 levels were significantly higher in controls than those in osteosarcoma patients (p<0.01). Genotypes of rs568408 GA and GA/AA, and rs3212227 CC and AC/CC were associated with the risk of osteosarcoma (rs568408 GA: odds ratios [OR]=1.86, 95% confidence intervals [CI]=1.11-3.12; GA/AA: OR=1.75, 95% CI=1.06-2.89, and rs3212227 CC: OR=2.70, 95% CI=1.38-5.28; CC/AC: OR=1.73, 95% CI=1.03-2.90). Moreover, rs3212227 CC/AC genotypes were significantly associated with decreased serum IL-12p40 levels in osteosarcoma patients compared to AA genotypes (p=0.035). Stratification analysis showed no associations between rs3212227 variant and the patients' gender, tumor location, and metastasis. Our data suggest that the serum IL-12p40 levels associate with the risk of osteosarcoma and are regulated by IL-12B rs3212227 polymorphism. The IL-12A rs568408 and IL-12B rs3212227 may confer the susceptibility to osteosarcoma risk.

Comprehensive assessment of the association between tumor necrosis factor alpha G238A polymorphism and liver cancer risk

Tumor necrosis factor alpha (TNF-α) has been suggested to play an important role in the development and liver cancer. TNF-α 238 G/A polymorphism was hypothesized to increase the risk of liver cancer, but findings from previous studies were controversial. To explore a more precise estimation of the relationship between TNF-α 238 G/A polymorphism and liver cancer, we performed a meta-analysis. PubMed, Embase, and China Biology Medicine databases were searched for all publications on this association through March 12, 2013. Odds ratios (ORs) with its 95% confidence intervals (CIs) were used to assess the strength of this association. Eleven studies with 1,406 liver cancer cases and 2,386 noncancer controls were included into this meta-analysis. Overall, there was a significant association between TNF-α 238 G/A polymorphism and increased risk of liver cancer under all three genetic models (A vs. G, OR 1.51, 95% CI 1.20-1.89, P < 0.001, I(2) = 37.7%; AG vs. GG, OR 1.49, 95% CI 1.01-2.21, P = 0.045, I(2) = 53.2%; AA/AG vs. GG, OR 1.76, 95% CI 1.35-2.30, P < 0.001, I(2) = 36.5%). The sensitivity analysis further strengthened the validity of the positive association. Subgroup analysis of nine studies from Asian countries showed that there was a significant association between TNF-α 238 G/A polymorphism and increased risk of liver cancer in Asians (A vs. G, OR 1.35, 95% CI 1.03-1.76, P = 0.027, I(2) = 40.2%; AA/AG vs. GG, OR 1.56, 95% CI 1.14-2.15, P = 0.006, I(2) = 41.9%). In conclusion, TNF-α 238 G/A polymorphism is significantly associated with increased risk of liver cancer, especially in Asians.

IL-4 -590C/T polymorphism and susceptibility to liver disease: a meta-analysis and meta-regression

Interleukin-4 (IL-4) is a pleiotropic cytokine that plays an important role in the immune system. Emerging evidences have shown that the common polymorphism (-590C/T; rs2243250 C>T) in the IL-4 gene may play an important role in the development of various liver diseases, but individually published studies revealed inconclusive results. This meta-analysis aims to derive a more precise estimation of the association between the IL-4 -590C/T polymorphism and susceptibility to liver disease. A literature search of PubMed, Embase, Web of Science and China BioMedicine databases was conducted on articles published before January 1st, 2013. Crude odds ratio with 95% confidence intervals were calculated to assess the strength of this association. Ten case-control studies were assessed with a total 1,140 patients and 1,649 healthy controls. The meta-analysis results indicated that the IL-4 -590T polymorphism might increase the risks of hepatitis B (HBV) and hepatitis C (HCV) infections. Further subgroup analyses showed significant associations between the IL-4 -590T polymorphism and increased risks of liver diseases among Caucasian populations, but similar associations were not found among Asian populations. Univariate and multivariate meta-regression analyses showed that differences in ethnicity and clinical subtype are the major sources of heterogeneity. No publication bias was detected in this meta-analysis. In conclusion, the current meta-analysis indicates that the IL-4 -590T polymorphism may play an important role in increasing HBV and HCV infection risks, especially among Caucasian populations.

Genetic association of interleukin-6 polymorphism (-174 G/C) with chronic liver diseases and hepatocellular carcinoma

Interleukin-6 (IL-6) is a pleiotropic cytokine which is expressed in many inflammatory cells in response to different types of stimuli, regulating a number of biological processes. The IL-6 gene is polymorphic in both the 5’ and 3’ flanking regions and more than 150 single nucleotide polymorphisms have been identified so far. Genetic polymorphisms of IL-6 may affect the outcomes of several diseases, where the presence of high levels of circulating IL-6 have been correlated to the stage and/or the progression of the disease itself. The -174 G/C polymorphism is a frequent polymorphism, that is located in the upstream regulatory region of the IL-6 gene and affects IL-6 production. However, the data in the literature on the genetic association between the -174 G/C polymorphism and some specific liver diseases characterized by different etiologies are still controversial. In particular, most of the studies are quite unanimous in describing a correlation between the presence of the high-producer genotype and a worse evolution of the chronic liver disease. This is valid for patients with hepatitis C virus (HCV)-related chronic hepatitis and liver cirrhosis and hepatocellular carcinoma (HCC) whatever the etiology. Studies in hepatitis B virus-related chronic liver diseases are not conclusive, while specific populations like non alcoholic fatty liver disease/non-alcoholic steatohepatitis, autoimmune and human immunodeficiency virus/HCV co-infected patients show a higher prevalence of the low-producer genotype, probably due to the complexity of these clinical pictures. In this direction, a systematic revision of these data should shed more light on the role of this polymorphism in chronic liver diseases and HCC.

Three common polymorphisms in the IL-4 gene and cancer risk: a meta-analysis involving 5,392 cases and 6,930 controls

Interleukin-4 (IL-4) is a typical pleiotropic T helper 2 (Th2) cytokine. This cytokine is a critical mediator of the Th1/Th2 balance and apoptosis potential and involved in the process of inflammation-mediated carcinogenesis in human organs. IL-4 gene polymorphisms influence IL-4 transcription and have been implicated in cancer risks. However, current published data show conflicts among of them. To assess the relationship between IL-4 polymorphisms and cancer risks, we performed a meta-analysis which includes 14 studies involving 3,562 cancer cases for IL-4 rs2243250 polymorphism, 6 studies involving 2,052 subjects for IL-4 rs2070874 polymorphism, and 5 studies involving 791 subjects for IL-4 intron-3 polymorphism. As for rs2243250 polymorphism, no significant association of cancer risk was found in the overall analysis. When stratified by cancer type, we observed that the IL-4 rs2243250 polymorphism was significantly associated with decreased oral cancer risk and increased renal cell cancer risk (for oral cancer, TT vs. CC: odds ratio (OR) = 0.40, 95 % confidence interval (95 % CI) 0.19-0.84, P heterogeneity = 0.662, P = 0.016; TT/CT vs. CC: OR = 0.45, 95 % CI 0.22-0.94, P heterogeneity = 0.407, P = 0.033; and for renal cell cancer, TT vs. CC: OR = 1.98, 95 % CI 1.06-3.69, P heterogeneity = 0.535, P = 0.031; TT vs.

CC/CT

OR = 1.43, 95 % CI 1.05-1.95, P heterogeneity = 0.959, P = 0.022). For rs2070874 and intron-3 polymorphisms, no significant association of cancer risk was found in the overall analysis. However, in the subgroup analysis by source of controls and ethnicities, a significant association between cancer risk and rs2070874 polymorphism was found in population-based studies (A allele vs. G allele: OR = 1.18, 95 % CI 1.03-1.35, P heterogeneity = 0.621, P = 0.0172; AA vs.

AG/GG

OR = 1.23, 95 % CI 1.03-1.47, P heterogeneity = 0.196, P = 0.024) and Caucasian populations (A allele vs. G allele: OR = 1.24, 95 % CI 1.03-1.48, P heterogeneity = 0.925, P = 0.022), but not in Asian populations. Taken together, our results indicated that IL-4 rs2243250 polymorphism was associated with decreased oral cancer risk in both the homozygote contrasts and the dominant genetic model, as well as increased renal cell cancer risk in both the homozygote contrasts and the recessive genetic model. The A allele of rs2070874 polymorphism in the IL-4 gene may be a risk factor for cancer development among Caucasians. Further larger, preferably prospective studies are needed to confirm these results.

Genetic polymorphisms of epidermal growth factor in relation to risk of hepatocellular carcinoma: two case-control studies

BACKGROUND

Earlier, we reported a highly statistically significant association between T-helper 1 (Th1) and Th2 cytokine genotypes and hepatocellular carcinoma (HCC) risk among natives of southern Guangxi, China, a hyperendemic region for HCC. Epidermal growth factor (EGF) plays a critical role in malignant transformation of hepatocytes and tumor progression. A polymorphism in the EGF gene (61A > G) results in elevation of EGF in liver tissues and blood. Epidemiological data are sparse on the possible association between EGF genetic polymorphism and HCC risk.

METHODS

The EGF 61A > G polymorphism, multiple Th1 and Th2 genotypes, and environmental risk factors for HCC were determined on 117 HCC cases and 225 healthy control subjects among non-Asians of Los Angeles County, California, a low-risk population for HCC, and 250 HCC cases and 245 controls of southern Guangxi, China.

RESULTS

Following adjustment for all known or suspected HCC risk factors, non-Asians in Los Angeles who possessed at least one copy of the high activity 61*G allele of the EGF gene showed a statistically non-significant, 78% increased risk of HCC compared with those possessing the EGF A/A genotype. This EGF-HCC risk association significantly strengthened among heavy users of alcohol [odds ratio (OR) = 3.44, 95% confidence interval (CI) = 0.93-12.76, P = 0.065)], and among individuals carrying the high-risk Th1/Th2 genotypes for HCC (OR = 3.34, 95% CI = 1.24-9.03, P = 0.017). No association between EGF genotype and HCC risk was observed among Chinese in southern Guangxi, China.

CONCLUSION

Genetic polymorphism in the EGF gene resulting in elevated level of EGF, may contribute to HCC risk among low-risk non-Asians in Los Angeles.

Lack of association between genetic polymorphisms in cytokine genes and tumor recurrence in patients with hepatocellular carcinoma undergoing transplantation

BACKGROUND

Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) remains one of the most common causes of poor long-term survival. However, the host genetic factors affecting increased risk of tumor recurrence after transplantation have not been thoroughly elucidated. The present study was designed to investigate the association of cytokine gene polymorphisms with the risk of tumor recurrence in LT patients for HCC.

METHODS

Eleven single-nucleotide polymorphisms within the promoter regions of 7 cytokine genes, i.e., the IL-1 family (IL-1alpha and IL-1beta), IL-6, IL-8, IL-10, TNF-alpha, and TGF-beta1, were genotyped in 93 HCC patients treated with LT using DNA sequencing. The association between these polymorphisms and the risk of tumor recurrence was evaluated while controlling confounding clinical variables.

RESULTS

The genotype frequency of IL-10 -1082 A/G in patients with and without recurrence of HCC was AA 83.3%, GA 16.7% and AA 97.6%, GA 2.4%, respectively. The association between IL-10 -1082 GA and recurrence was significant (P=0.033). No other single-nucleotide polymorphism in the cytokine gene was found to be associated with recurrence. Kaplan-Meier survival curves showed that the homozygous AA patients had a significantly longer mean recurrence-free survival than heterozygous GA patients (23.5 vs 5.7 months, P=0.001). However, multivariate analysis failed to reveal that the GA genotype of IL-10 -1082 A/G was an independent indicator of recurrence.

CONCLUSIONS

This study suggests the lack of association of selected cytokine gene polymorphisms with HCC recurrence after LT in the Han Chinese population. The finding does not exclude the idea that other cytokine polymorphisms could act as candidate biomarkers of disease prognosis.

Functional polymorphisms in the interleukin-12 gene contribute to cancer risk: evidence from a meta-analysis of 18 case-control studies

BACKGROUND

Emerging evidence from preclinical and clinical studies has shown that interleukin-12 (IL-12) has some effectiveness against endogenously arising carcinogenesis. Several potentially functional polymorphisms of IL-12 gene have been implicated in cancer risk, but individually published studies showed inconclusive results. The aim of this study was to investigate the association between IL-12 polymorphisms and cancer risk.

METHODS

The MEDLINE, EMBASE, Web of science and CBM databases were searched for all articles published up to June 10, 2012 that addressed IL-12 polymorphisms and cancer risk. Statistical analyses were performed using RevMan 5.1.6 and STATA 12.0 softwares.

RESULTS

Eighteen studies were included with a total of 6463 cancer cases and 7412 healthy controls. We found that the 3'UTR A>C (rs3212227) polymorphism of IL-12B gene was associated with significantly increased overall risk of cancers using random effects model (C vs A: odds ratio [OR]=1.14, 95% confidence interval [CI]: 1.02-1.27; AC+CC vs AA: OR=1.20, 95%CI: 1.01-1.43). However, the 3'UTR G>A (rs568408), IVS2 T>A (rs582054) and 5'UTR T>G (rs2243115) polymorphisms of IL-12A gene did not appear to have an influence on cancer susceptibility. Further subgroup analyses showed that the 3'UTR A>C (rs3212227) polymorphism was associated with increased cancer risks in the subgroups of Asians, cervical and nasopharyngeal cancers.

CONCLUSIONS

Results from the current meta-analysis indicates that the 3'UTR A>C (rs3212227) polymorphism of IL-12B gene might be a potential biomarker for cancer risk among Asians, especially for cervical and nasopharyngeal cancers.

Interleukin-12: clinical usage and molecular markers of cancer susceptibility

The last decade has seen the emergence of immunomodulators as therapeutic agents in cancer treatment. Interleukins (ILs) are a category of small cell-signaling molecules that organize communication and interaction between immune cells and therefore they could be used as perfect immunomodulators. IL-12 is a promising candidate for cancer immunotherapy since it plays a major role in development of antitumor immune response. Numerous studies report that IL-12 promotes an effective destruction of cancer cells both in vivo and in vitro. In addition, IL-12 has anti-angiogenic activity and it is able to dramatically decrease tumor-supportive activities of tumor-associated macrophages. The first part of the review is devoted to immunobiology of IL-12. Signaling pathways of IL-12 as well as clinical trials of this cytokine are discussed. The second part of the review is concerned on the inherited variations in IL-12A and IL-12B genes that could modulate cancer susceptibility, and as a consequence, possess predictive, therapeutic, or prognostic significance. It is known that functional single nucleotide polymorphisms (SNPs) in IL-12A and IL-12B genes may dramatically affect on protein expression level, or alter its functions, which may lead to immune disorders, autoimmune diseases, and eventually contribute to cancer occurrence. The list of genetic polymorphisms for further investigations might include the following: IL-12B_+1188A/C (rs3212227), IL-12A_+277G/A (rs568408), IL-12A_-798T/A (rs582054), IL-12A_-504T/G (rs190533), IL-12A_-1148T/C (rs2243123), and IL-12B_+16974 A/C. Perhaps, some of these SNPs may become an attractive target for oncogenomics and possibly could be used in programs of early cancer diagnosis as well as cancer prevention in the nearest future.

Is interleukin-10 gene polymorphism a predictive marker in HCV infection?

The clinical outcome of hepatitis C virus (HCV) infection varies between individuals - from spontaneous viral clearance and persistence without complication, to chronic hepatitis, cirrhosis and hepatocellular carcinoma. Also patterns of response to interferon-based anti-HCV therapy are different from person to person. This diversity may be affected by host genetic factors, including alterations in genes encoding cytokines. Interleukin-10, as an anti-inflammatory cytokine and immune response modulator, may influence on HCV infection susceptibility as well as spontaneous and treatment-induced HCV eradication. Moreover, it is stated that IL-10 has antifibrotic properties and play a role in progression of liver disease. This review summarized studies on interleukin-10 gene polymorphisms (mainly promoter SNPs at positions -1082(G/A), -819(C/T) and -592(C/A)), which may determine IL-10 production, regarding susceptibility to HCV infection, course of HCV-related liver disease (fibrosis, cirrhosis, hepatocellular carcinoma, ALT abnormalities), spontaneous viral elimination as well as hepatitis C treatment outcomes. Analysis of hereby summarized studies shows that it is difficult to unambiguously determine the importance of IL-10 polymorphism as a predictor of clinical outcome of hepatitis C and response to anti-HCV therapy before its beginning. Thus, future larger studies need to address these issues. Continuation of studies on interleukin-10 polymorphisms as well as identification of other candidate predictive markers in HCV infection has important practical implications and there is a chance that may contribute to reduce the scale of hepatitis C problem.

Interleukin-10 gene polymorphisms and hepatocellular carcinoma susceptibility: A meta-analysis

AIM: To assess the association between Interleukin-10 (IL-10) gene IL-10-1082 (G/A), IL-10-592(C/A), IL-10-819 (T/C) polymorphisms and hepatocellular carcinoma (HCC) susceptibility.

METHODS: Two investigators independently searched the Medline, Embase, China National Knowledge Infrastructure, and Chinese Biomedicine Database. Summary odds ratios (ORs) and 95% confidence intervals (95% CIs) for IL-10 polymorphisms and HCC were calculated in a fixed-effects model (the Mantel-Haenszel method) and a random-effects model (the DerSimonian and Laird method) when appropriate.

RESULTS: This meta-analysis included seven eligible studies, which included 1012 HCC cases and 2308 controls. Overall, IL-10-1082 G/A polymorphism was not associated with the risk of HCC (AA vs AG + GG, OR = 1.11, 95% CI = 0.90-1.37). When stratifying for ethnicity, the results were similar (Asian, OR = 1.12, 95% CI = 0.87-1.44; non-Asian, OR = 1.10, 95% CI = 0.75-1.60). In the overall analysis, the IL-10 polymorphism at position -592 (C/A) was identified as a genetic risk factor for HCC among Asians; patients carrying the IL-10-592*C allele had an increased risk of HCC (OR = 1.29, 95% CI = 1.12-1.49). No association was observed between the IL-10-819 T/C polymorphism and HCC susceptibility (TT vs TC + CC, OR = 1.02, 95% CI = 0.79-1.32).

CONCLUSION: This meta-analysis suggests that IL-10-592 A/C polymorphism may be associated with HCC among Asians. IL-10-1082 G/A and IL-10-819 T/C polymorphisms were not detected to be related to the risk for HCC.

Polymorphisms of tumor necrosis factor-alpha and hepatocellular carcinoma risk: a HuGE systematic review and meta-analysis

BACKGROUND

Studies investigating the associations between tumor necrosis factor-alpha (TNFA) polymorphisms and hepatocellular carcinoma (HCC) risk report conflicting results. We conducted a meta-analysis to assess the association between TNFA gene TNFA-308(G/A), TNFA-238(G/A), TNFA-863(C/A), TNFA-857(C/T), TNFA-1031 (T/C) polymorphisms and HCC susceptibility.

METHODS

Two investigators independently searched the Medline, Embase, CNKI, and Chinese Biomedicine Database. Summary odds ratios (ORs) and 95% confidence intervals (95% CIs) for TNFA polymorphisms and HCC were calculated in a fixed-effects model (the Mantel-Haenszel method) and a random-effects model (the DerSimonian and Laird method) when appropriate.

RESULTS

This meta-analysis included 17 case-control studies, which included 2,357 HCC cases and 3,161 controls. Overall, the variant genotypes AA/AG of -308G/A were associated with a significantly increased HCC risk, when compared with GG genotype (AA vs. GG, OR=1.97, 95%CI=1.01-3.83; AG vs. GG, OR=1.88, 95%CI=1.23-2.88; AA/AG vs. GG, OR=1.80, 95%CI=1.19-2.72). When stratifying for ethnicity, significantly elevated HCC risk was found among Asians. Moreover, similar results were observed between TNFA-238G/A, TNFA-863C/A polymorphisms and HCC risk among Asians (for -238G/A, AG vs. GG OR=1.63, 95%CI=1.17-2.26, AA/AG vs. GG OR=1.61, 95%CI=1.16-2.24; for -863 C/A, AC vs. CC OR=1.72, 95%CI=1.03-2.88, AA/AC vs. CC OR=1.71, 95%CI=1.02-2.86), while no associations were observed between TNFA-857C/T, TNFA-1031T/C polymorphisms and HCC susceptibility.

CONCLUSIONS

This meta-analysis shows that TNFA-308G/A, TNFA-238G/A and TNFA-863C/A polymorphisms may be associated with HCC among Asians. TNFA-857C/T and TNFA-1031T/C polymorphisms were not detected to be related to the risk for HCC.