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

Gene variations related to the hepatocellular carcinoma: Results from a field synopsis and Bayesian revaluation

Hepatocellular carcinoma (HCC) is considered as the second cause of cancer-related deaths worldwide. Genetic variations are associated with HCC risk, an issue that has been the subject of several meta-analyses. However, meta-analyses have an important limitation on the likelihood of false positive data. Henceforth, this study aimed to assess the level of noteworthiness in the meta-analyses by means of a Bayesian approach. A systematic search was performed for meta-analyses with associations between gene polymorphisms and HCC. The calculations for the False-Positive Rate Probability (FPRP) and the Bayesian False Discovery Probability (BFDP) were performed to assess the noteworthiness with a statistical power of 1.2 and 1.5 of Odds Ratio at a prior probability of 10^-3 and 10^-5. The quality of studies was evaluated by the Venice criteria. As additional analyses, the gene-gene and protein-protein networks were designed for these genes and products. As results, we found 33 meta-analytic studies on 45 polymorphisms occurring in 35 genes. A total of 1,280 values for FPRP and BFDP were obtained. Seventy-five for FPRP (5.86%) and 95 for BFDP (14.79%) were noteworthy. In conclusion, the polymorphisms in CCND1, CTLA4, EGF, IL6, IL12A, KIF1B, MDM2, MICA, miR-499, MTHFR, PNPLA3, STAT4, TM6SF2, and XPD genes were considered as noteworthy biomarkers for HCC risk.

Mechanisms by Which Probiotic Bacteria Attenuate the Risk of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and the second leading cause of cancer-related deaths worldwide. Chronic infections with hepatitis B virus (HBV) and hepatitis C virus (HCV), alcoholic liver disease (ALD), and non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) are the major extrinsic risk factors of HCC development. Genetic background is pivotal in HCC pathogenesis, and both germline mutations and single nucleotide polymorphism (SNP) are intrinsic risk factors of HCC. These HCC risk factors predispose to hepatic injury and subsequent activation of fibrogenesis that progresses into cirrhosis and HCC. Probiotic bacteria can mitigate HCC risk by modulating host gut microbiota (GM) to promote growth of beneficial microbes and inhibit HCC-associated dysbiosis, thus preventing pathogen-associated molecular patterns (PAMPs)-mediated hepatic inflammation. Probiotics have antiviral activities against HBV and HCV infections, ameliorate obesity and risk of NAFLD/NASH, and their antioxidant, anti-proliferative, anti-angiogenic, and anti-metastatic effects can prevent the HCC pathogenesis. Probiotics also upregulate the expression of tumor suppressor genes and downregulate oncogene expression. Moreover, metabolites generated by probiotics through degradation of dietary phytochemicals may mitigate the risk of HCC development. These multiple anticancer mechanisms illustrate the potential of probiotics as an adjuvant strategy for HCC risk management and treatment.

Association between five types of Tumor Necrosis Factor-α gene polymorphism and hepatocellular carcinoma risk: a meta-analysis

BACKGROUND

Research focusing on the relationship between five types of tumor necrosis factor-alpha (TNF-α) SNPs and the risk of hepatocellular carcinoma (HCC) were still controversial. Hereby, we performed a meta-analysis to determine the association between TNF-α promoter SNPs: -1031 T/C, - 863 C/A, - 857 C/T, - 308 G/A, and - 238 G/A with HCC risk.

METHODS

We interrogated articles from journal database: PubMed, Pro-Quest, EBSCO, Science Direct, and Springer to determine the relationship between five types of SNPs in TNF-α gene with HCC risk. RevMan 5.3 software was used for analysis in fixed/random effect models.

RESULTS

This meta-analysis included 23 potential articles from 2004 to 2018 with 3237 HCC cases and 4843 controls. We found that SNP - 863 C/A were associated with a significantly increased HCC risk (A vs C, OR = 1.31, 95% CI = 1.03-1.67). Similar results were obtained in - 857 C/T (TT/CT vs CC, OR = 1.31, 95% CI = 1.06-1.62), - 308 G/A (AA vs GG, OR = 3.14, 95% CI = 2.06-4.79), and - 238 G/A (AA vs GG, OR = 3.87, 95% CI = 1.32-11.34). While no associations were observed between SNP TNF-α - 1031 T/C and HCC risk.

CONCLUSIONS

The present meta-analysis showed that TNFα SNPs -863C/A, - 857 C/T, - 308 G/A, and - 238 G/A were associated with the risk of HCC.

Environment and Gene Association With Obesity and Their Impact on Neurodegenerative and Neurodevelopmental Diseases

Obesity is a multifactorial disease in which environmental conditions and several genes play an important role in the development of this disease. Obesity is associated with neurodegenerative diseases (Alzheimer, Parkinson, and Huntington diseases) and with neurodevelopmental diseases (autism disorder, schizophrenia, and fragile X syndrome). Some of the environmental conditions that lead to obesity are physical activity, alcohol consumption, socioeconomic status, parent feeding behavior, and diet. Interestingly, some of these environmental conditions are shared with neurodegenerative and neurodevelopmental diseases. Obesity impairs neurodevelopment abilities as memory and fine-motor skills. Moreover, maternal obesity affects the cognitive function and mental health of the offspring. The common biological mechanisms involved in obesity and neurodegenerative/neurodevelopmental diseases are insulin resistance, pro-inflammatory cytokines, and oxidative damage, among others, leading to impaired brain development or cell death. Obesogenic environmental conditions are not the only factors that influence neurodegenerative and neurodevelopmental diseases. In fact, several genes implicated in the leptin–melanocortin pathway (LEP, LEPR, POMC, BDNF, MC4R, PCSK1, SIM1, BDNF, TrkB, etc.) are associated with obesity and neurodegenerative and neurodevelopmental diseases. Moreover, in the last decades, the discovery of new genes associated with obesity (FTO, NRXN3, NPC1, NEGR1, MTCH2, GNPDA2, among others) and with neurodegenerative or neurodevelopmental diseases (APOE, CD38, SIRT1, TNFα, PAI-1, TREM2, SYT4, FMR1, TET3, among others) had opened new pathways to comprehend the common mechanisms involved in these diseases. In conclusion, the obesogenic environmental conditions, the genes, and the interaction gene–environment would lead to a better understanding of the etiology of these diseases.

The ATG16L1 gene variant rs2241880 (p.T300A) is associated with susceptibility to HCC in patients with cirrhosis

BACKGROUND AND AIMS

Protein and organelle turnover by autophagy is a key component to maintain cellular homeostasis. Loss of the autophagy protein ATG16L1 is associated with reduced bacterial killing and aberrant interleukin-1β production, perpetuating inflammation and carcinogenesis. Here we hypothesized that the functional p.T300A gene variant in ATG16L1 is associated with an increased risk for hepatocellular carcinoma (HCC) in cirrhosis.

METHODS

A case-control study was performed using a prospective derivation cohort (107 patients with HCC and 101 controls) and an independent validation cohort (124 patients with HCC and 108 controls) of patients with cirrhosis of any aetiology. ATG16L1 p.T300A (rs2241880) and PNPLA3 p.I148M (rs738409) variants were determined by real-time PCR.

RESULTS

The G allele of the ATG16L1 p.T300A variant was more frequent in patients with HCC compared to controls without HCC in the derivation cohort (0.62 vs. 0.51, P = .022) and in the validation cohort (0.59 vs. 0.50, P = .045). In combined analysis, the odds ratios (OR) were 1.76 (95% CI: 1.07-2.88) for G allele positivity and 2.43 (95% CI: 1.37-4.31) for p.T300A G allele homozygosity. This association was independent from the presence of a PNPLA3 variant, which was also associated with HCC (OR 2.10; 95% CI: 1.20-3.66), and it remained significant after adjustment for male sex, age and aetiology in multivariate analysis.

CONCLUSION

The common germ-line ATG16L1 gene variant is a risk factor for HCC in patients with cirrhosis. Personalized strategies employing the genetic risk conferred by ATG16L1 and PNPLA3 may be used for risk-based surveillance in cirrhosis.

Systematic analyses and comprehensive field synopsis of genetic association studies in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancy in the world. In order to comprehensively examine the association between genetic variants and risk of HCC, a systematic literature search and meta-analyses of the evidences have been performed. With the data from 301 articles, we conducted meta-analyses for 69 polymorphisms involving 46 distinct genes. The result showed that 31 polymorphisms in 25 genes are significantly associated with HCC risk. Cumulative epidemiological evidence for a significant association with HCC risk was graded strong for one polymorphism (NQO1 rs1800566). Furthermore, we provided a database to integrate and analyze the association of genetic variants and HCC risk. To the best of our knowledge, this is the first comprehensive field synopsis and systematic meta-analysis of genetic association with HCC risk. We have provided a useful resource and platform for investigators to explore the association of sequence polymorphisms and HCC risk.

Development of gene polymorphisms in meditators of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide, the morbidity of which closely correlates with diversity of ethnicity, minority, family and location. Its histology spans from simple steatosis, to nonalcoholic steatohepatitis, which ultimately results in fibrosis, cirrhosis and hepatocellular carcinoma. The accelerating prevalence of NAFLD is due to an incremental incidence of metabolic syndrome that is distinguished by dyslipidemia, glucose impairment, obesity, excessive oxidative stress and adipocytokine impairment. Additionally, the pathogenesis of NAFLD is thought to be a multifactorial and complicated disease associated with lifestyle habits, nutritional factors and genetics. However, the pathogenesis and underlying mechanism in the development of NAFLD caused by genetics remains unclear. People have been increasingly emphasizing on the relationship between NAFLD and gene polymorphisms in recent years, with the aim of having a comprehensive elucidation of associated gene polymorphisms influencing the pathogenesis of the disease. In the current article, the authors attempted to critically summarize the most recently identified gene polymorphisms from the facets of glucose metabolism, fatty acid metabolism, oxidative stress and related cytokines in NAFLD that contribute to promoting the progression of the disease.

Tumor Necrosis Factor-α T-857C (rs1799724) Polymorphism and Risk of Cancers: A Meta-Analysis

Objectives. To investigate the potential association of tumor necrosis factor-α T-857C polymorphism with susceptibility to the five common malignant tumors. Materials and Methods. A comprehensive search of PubMed/Medline, Embase, and Web of Science databases was performed up to November 2015. Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated to assess the strength of the association. Subgroup analysis, heterogeneity analyses, and publication bias were also texted in the meta-analysis. Results. A total of twenty-two publications involving 5215 cases and 6755 controls were recruited. Overall, the meta-analysis revealed an increased risk between the TNF-α T-857C polymorphism and gastric cancer susceptibility in T versus C model, heterozygote genetic model, and dominant genetic model. An increased risk between the TNF-α T-857C polymorphism and hepatocellular cancer susceptibility in homozygote genetic model and recessive genetic model was also found. No significant association was found between the TNF-α T-857C polymorphism and colorectal cancer, cervical cancer, and prostate cancer. Conclusions. Our meta-analyses suggest that TNF-α T-857C polymorphism may be associated with increased risk of gastric cancer and hepatocellular cancer development. Therefore, the TNF-α T-857C polymorphism could be considered as one possible risk factor of gastric cancer and hepatocellular cancer according to our study.

Three polymorphisms of tumor necrosis factor-alpha and hepatitis B virus related hepatocellular carcinoma: A meta-analysis

BACKGROUND

To assess the association between tumor necrosis factor-alpha (TNF-α) G308A, G238A and C863T polymorphisms and hepatitis B virus related hepatocellular carcinoma (HBV-HCC) susceptibility.

METHODS

We interrogated the databases of Pubmed, Sciencedirect and Viley online library up to March 8, 2016. Odds ratios (ORs) and corresponding 95% confidence intervals (95%CIs) were calculated in a fixed-effects model or a random-effects model when appropriate.

RESULTS

In total, 12 case-control studies which containing 1580 HBV-HCC cases, 2033 HBV carrier controls, 395 HBV spontaneously recovered (SR) controls and 1116 healthy controls were included. Compared with GG genotype, the genotypes GA/AA of G308A were associated with a significantly increased HBV-HCC risk when the controls were all healthy individuals (AA vs. GG, OR 2.483, 95%CI 1.243 to 4.959; GA vs. GG, OR 1.383, 95%CI 1.028 to 1.860; GA/AA vs. GG, OR 1.381, 95%CI 1.048 to 1.820). Meanwhile, only the AA vs. GG model of G238A and HBV-HCC showed a statistic significance when the controls were healthy individuals (OR 4.776, 95%CI 1.280 to 17.819). CT genotype of TNF-α C863T could increase HBV-HCC risk whenever the controls were healthy individuals, HBV carriers or HBV recovers.

CONCLUSION

This meta-analysis shows that AA genotype in TNF-α G308A and TNF-α G238A and CT genotype in TNF-α C863T may increase HBV-HCC risk. Therefore, HBV infection seemed to be a more important factor for tumorigenesis of HCC than genetic predisposition in G308A of TNF-α, and interaction between TNF-α C863T polymorphisms and HBV infection might be associated with increased HCC risk.

Molecular pathological epidemiology in diabetes mellitus and risk of hepatocellular carcinoma

Molecular pathological epidemiology (MPE) is a multidisciplinary and transdisciplinary study field, which has emerged as an integrated approach of molecular pathology and epidemiology, and investigates the relationship between exogenous and endogenous exposure factors, tumor molecular signatures, and tumor initiation, progression, and response to treatment. Molecular epidemiology broadly encompasses MPE and conventional-type molecular epidemiology. Hepatocellular carcinoma (HCC) is the third most common cause of cancer-associated death worldwide and remains as a major public health challenge. Over the past few decades, a number of epidemiological studies have demonstrated that diabetes mellitus (DM) is an established independent risk factor for HCC. However, how DM affects the occurrence and development of HCC remains as yet unclearly understood. MPE may be a promising approach to investigate the molecular mechanisms of carcinogenesis of DM in HCC, and provide some useful insights for this pathological process, although a few challenges must be overcome. This review highlights the recent advances in this field, including: (1) introduction of MPE; (2) HCC, risk factors, and DM as an established independent risk factor for HCC; (3) molecular pathology, molecular epidemiology, and MPE in DM and HCC; and (4) MPE studies in DM and risk of HCC. More MPE studies are expected to be performed in future and I believe that this field can provide some very important insights on the molecular mechanisms, diagnosis, personalized prevention and treatment for DM and risk 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.

Donor interleukin 6 gene polymorphisms predict the recurrence of hepatocellular carcinoma after liver transplantation

BACKGROUND

Application of the Milan criteria is an effective strategy to select patients with hepatocellular carcinoma (HCC) for liver transplantation, but HCC recurrence is still a major concern. The aim of this study was to determine whether interleukin 6 (IL6) polymorphisms and clinical variables are potential predictors for HCC recurrence and prognosis after transplantation.

METHODS

A total of 110 consecutive patients with HCC undergoing liver transplantation were enrolled in the study. Six tag single nucleotide polymorphisms in IL6 were genotyped in both the donors and recipients. Demographic characteristics, HCC features, and IL6 polymorphisms were assessed against HCC recurrence.

RESULTS

Pretransplant hepatitis B virus DNA (P = 0.014), pretransplant serum alpha-fetoprotein (P = 0.035), number of nodules (P = 0.011), diameter of main nodule (P = 0.001), macrovascular invasion (P = 0.001), microvascular invasion (P = 0.001), HCC exceeding the Milan criteria (P < 0.001), and donor rs2069852 AA genotype (P = 0.010) were associated with HCC recurrence. Recurrence-free survival rate and overall survival rate were significantly lower (P = 0.011 and P = 0.026, respectively) in patients whose donor had the rs2069852 AA genotype than in those whose donor had the AG and GG genotypes. Independent risk factors for recurrence-free survival and overall survival were microvascular invasion (P = 0.003; P = 0.002), HCC exceeding the Milan criteria (P < 0.001; P = 0.001), and donor rs2069852 AA genotype (P = 0.002; P = 0.010).

CONCLUSIONS

Our data suggest that donor IL6 rs2069852 polymorphisms may be a potential genetic marker for HCC recurrence after liver transplantation in the Han Chinese population.

Host nucleotide polymorphism in hepatitis B virus-associated hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is etiologically linked with hepatitis B virus (HBV) and is the leading cause of death amongst 80% of HBV patients. Among HBV affected patients, genetic factors are also involved in modifying the risk factors of HCC. However, the genetic factors that regulate progression to HCC still remain to be determined. In this review, we discuss several single nucleotide polymorphisms (SNPs) which were reportedly associated with increased or reduced risk of HCC occurrence in patients with chronic HBV infection such as cyclooxygenase (COX)-2 expression specifically at COX-2 -1195G/A in Chinese, Turkish and Egyptian populations, tumor necrosis factor α and the three most commonly studied SNPs: PAT-/+, Lys939Gln (A33512C, rs2228001) and Ala499Val (C21151T, rs2228000). In genome-wide association studies, strong associations have also been found at loci 1p36.22, 11q22.3, 6p21 (rs1419881, rs3997872, rs7453920 and rs7768538), 8p12 (rs2275959 and rs37821974) and 22q11.21. The genes implicated in these studies include HLA-DQB2, HLA-DQA1, TCF19, HLA-C, UBE2L3, LTL, FDX1, MICA, UBE4B and PG. The SNPs found to be associated with the above-mentioned genes still require validation in association studies in order to be considered good prognostic candidates for HCC. Screening of these polymorphisms is very beneficial in clinical experiments to stratify the higher or lower risk for HCC and may help in designing effective and efficient HCC surveillance programs for chronic HBV-infected patients if further genetic vulnerabilities are detected.

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.

Oncogenic circuit constituted by Ser31-HBx and Akt increases risks of chronic hepatitis and hepatocellular carcinoma

The X protein of hepatitis B virus (HBx) has been specifically implicated in the development of hepatocellular carcinoma (HCC). Clinical associations of HBx isoforms with chronic hepatitis and HCC have not been well studied. HBx has two roles in liver cells, namely pro-apoptotic and anti-apoptotic. In this report, we examined the role of Ser31-HBx in HCC and chronic hepatitis. Using the case-control study, we determined risks of chronic hepatitis and HCC conferred by hepatitis B virus (HBV) containing Ser31-HBx that was phosphorylated by Akt. Ser31-HBx isoforms conferred 3.23-fold risk of HCC in male and 3.36-fold risk in female. Ser31 isoforms were associated with 3.12-fold risk of chronic hepatitis and 3.43-fold risk of cirrhosis and also associated with higher HBV viral load and replication efficiency and lower rate of HBe loss. To determine the mechanism, we found that Ser31-HBx constituted an oncogenic circuit with Akt and cooperated with ras to transform NIH3T3 cells in contrast to non-Ser31-HBxs that did not transduce oncogenic signals. Our results give a clue to account for an underlying cause of HBx-mediated hepatocarcinogenesis. It appears that Ser31 phosphorylation of HBx by Akt plays an important role. The current study provides an example of association of HBV genome variations with risks of HCC and chronic hepatitis.

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.

Association between hepatocellular carcinoma and tumor necrosis factor alpha polymorphisms in South Korea

AIM: To investigate associations between the tumor necrosis factor alpha (TNF-α) -1031 T>C, -863 C>A, -857 C>T, -308 G>A, and -238 G>A polymorphisms and HCC in Korea.

METHODS: Hepatocellular carcinoma (HCC) cases were diagnosed at CHA Bundang Medical Center from June 1996 to August 2008. The association between TNF-α polymorphisms and HCC was analyzed in 157 HCC patients and 201 controls using a polymerase chain reaction-restriction fragment length polymorphism assay. We investigated five TNF-α polymorphisms, which are TNF-α -1031 T>C, -863 C>A, -857 C>T, -308 G>A, and -238 G>A. The TNF-α genotype frequencies, genotype combinations and haplotypes were analyzed to disclose the association with HCC.

RESULTS: None of the TNF-α polymorphisms was significantly associated with HCC. However, nine genotype combinations had associations with increased likelihood of HCC. Among them, TNF-α -1031/-857/-238 TT/CC/GA (AOR = 18.849, 95%CI: 2.203-161.246, P = 0.007), TNF-α -1031/-308/-238 TT/GG/GA (AOR = 26.956, 95%CI: 3.071-236.584, P = 0.003), and TNF-α -1031/-238 TT/GA (AOR = 21.576, 95%CI: 2.581-180.394, P = 0.005) showed marked association with HCC. There were five haplotypes of TNF-α polymorphisms which were significantly associated with HCC. They are TNF-α -1031/-863/-857/-308/-238 T-C-C-G-A (OR = 25.824, 95%CI: 1.491-447.223, P = 0.0005), TNF-α -1031/-857/-308/-238 T-C-G-A (OR = 12.059, 95%CI: 2.747-52.950, P < 0.0001), TNF-α -1031/-857/-238 T-C-A (OR = 10.696, 95%CI: 2.428-47.110, P = 0.0001), TNF-α -1031/-308/-238 T-G-A (OR = 7.556, 95%CI: 2.173-26.280, P = 0.0002) and TNF-α -1031/-238 T-A (OR = 10.865, 95%CI: 2.473-47.740, P = 0.0001). Moreover, HCC Okuda stage III cases with the TNF-α -1031 CC genotype had better survival than those with the TT genotype (AOR = 5.795, 95%CI: 1.145-29.323).

CONCLUSION: Although no single TNF-α polymorphism is associated with HCC in this study, some TNF-α genotype combinations and haplotypes are associated with HCC. In addition, HCC Okuda stage III cases with the TNF-α -1031 TT genotype may have a better prognosis than those with the CC genotype.

WITHDRAWN: Association of TNF-α-308G>A polymorphisms with hepatocellular carcinoma in Han Chinese population: A systematic review and meta-analysis

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The Tumor Necrosis Factor-α-308 and -238 Polymorphisms and Risk of Hepatocellular Carcinoma for Asian Populations: A Meta-Analysis

BACKGROUND

Tumor necrosis factor-α (TNF-α) has been suggested to play a very important role in the development and progression of hepatocellular carcinoma (HCC). Many studies have identified the associations of TNF-α-308 and -238 polymorphisms with HCC risk, but the results remain controversial.

AIM

We conducted this meta-analysis to evaluate the associations between TNF-α-308 and -238 polymorphisms and HCC susceptibility.

METHODS

PubMed, Embase, and China National Knowledge Infrastructure electronic databases were searched for all articles on associations between TNF-α-308 and -238 polymorphisms and HCC risk in Asians through September 30, 2013. Odds ratios (ORs) and their 95% CIs were calculated to assess the strength of this association.

RESULTS

A total of 17 case-control studies were identified in our meta-analysis. For the TNF-α-308 G/A polymorphism, 14 studies containing 3154 cases and 3767 controls were included. Overall, the frequency of the A allele was higher in patients with HCC than in the healthy controls (10.2% vs 7.5%), and the A allele and allele carrier were significantly associated with increased risk of HCC in a random effects model (A vs G: OR = 1.57; 95% CI, 1.22-2.01; P = 0.0004; AA + AG vs GG: OR = 1.62; 95% CI, 1.18-2.22; P = 0.003). For the TNF-α-238 polymorphism, 10 research articles were identified. No association was found between the TNF-α-238 G/A polymorphism and risk of HCC in any genetic models (P > 0.05). The sensitivity analysis further strengthened the overall correlations.

CONCLUSIONS

Our meta-analysis proved that the TNF-α-308 G/A polymorphism is associated with increased susceptibility to HCC. However, the TNF-α-238 G/A polymorphism is not significantly associated with risk of HCC in Asian populations. Further studies with large sample sizes are needed to confirm these associations among other populations.

Impact of cytokine gene variants on the prediction and prognosis of hepatocellular carcinoma in patients with cirrhosis

BACKGROUND & AIMS

Genetic polymorphisms modulate the expression of proinflammatory cytokines. We prospectively assessed the influence of 6 single nucleotide polymorphisms (SNPs) in TNFα, IL6, and IL1β genes on the risk of hepatocellular carcinoma (HCC) in patients with cirrhosis.

METHODS

TNFα (G-238A, C-863A, G-308A), IL6 (C-174G), and IL1β (C-31T, C-511T) SNPs were assessed in 232 alcoholics and 253 HCV-infected patients with biopsy-proven cirrhosis, prospectively followed-up and screened for HCC. Their influence on HCC development was assessed using the Kaplan-Meier method.

RESULTS

These variants did not influence the risk of HCC in alcoholic patients. Conversely, two variants influenced the risk of HCC occurrence in patients with HCV-related cirrhosis, namely the TNFα-308 (A) allele (HR = 2.4 [1.6-3.7], Log-rank <0.0001) and the IL1β-31 (T) allele (HR = 1.5 [1.1-2.1], Log-rank = 0.004). When stratifying HCV-infected patients into four genotypic associations expected to progressively increase TNFα and IL1β production, we observed increasing risk of HCC occurrence (Log-rank <0.0001) from group 1 to 4. The TNFα-308 (A) allele was the only genetic trait independently associated with risk of HCC in these patients, along with older age, male gender, BMI, and platelet count. These variables led to construction of a predictive score able to separate patients with HCV-related cirrhosis into three subgroups with progressively increasing 5-year cumulative incidences of 4.7%, 14.1%, and 36.3%, respectively (Log-rank <0.0001).

CONCLUSIONS

Genetic heterogeneity in the TNFα and IL1β gene promoters influences the risk of HCC in patients with HCV-induced cirrhosis. These genetic data, when incorporated into clinical scores, are able to refine selection of risk classes of HCC.

Ethnic background and genetic variation in the evaluation of cancer risk: a systematic review

The clinical use of genetic variation in the evaluation of cancer risk is expanding, and thus understanding how determinants of cancer susceptibility identified in one population can be applied to another is of growing importance. However there is considerable debate on the relevance of ethnic background in clinical genetics, reflecting both the significance and complexity of genetic heritage. We address this via a systematic review of reported associations with cancer risk for 82 markers in 68 studies across six different cancer types, comparing association results between ethnic groups and examining linkage disequilibrium between risk alleles and nearby genetic loci. We find that the relevance of ethnic background depends on the question. If asked whether the association of variants with disease risk is conserved across ethnic boundaries, we find that the answer is yes, the majority of markers show insignificant variability in association with cancer risk across ethnic groups. However if the question is whether a significant association between a variant and cancer risk is likely to reproduce, the answer is no, most markers do not validate in an ethnic group other than the discovery cohort's ancestry. This lack of reproducibility is not attributable to studies being inadequately populated due to low allele frequency in other ethnic groups. Instead, differences in local genomic structure between ethnic groups are associated with the strength of association with cancer risk and therefore confound interpretation of the implied physiologic association tracked by the disease allele. This suggest that a biological association for cancer risk alleles may be broadly consistent across ethnic boundaries, but reproduction of a clinical study in another ethnic group is uncommon, in part due to confounding genomic architecture. As clinical studies are increasingly performed globally this has important implications for how cancer risk stratifiers should be studied and employed.

Significance of vitamin d receptor gene polymorphisms for risk of hepatocellular carcinoma in chronic hepatitis C

BACKGROUND/AIMS

Biological and epidemiological data suggest that vitamin D levels may influence cancer development. Several single nucleotide polymorphisms have been described in the vitamin D receptor (VDR) gene in association with cancer risk. We aimed to investigate the association of VDR gene polymorphisms with hepatocellular carcinoma (HCC) development in chronic hepatitis C patients.

METHODS

In a cross-sectional, hospital-based setting, 340 patients (201 chronic hepatitis, 47 cirrhosis and 92 HCC) and 100 healthy controls receiving VDR genotyping (bat-haplotype: BsmI rs1544410 C, ApaI rs7975232 C and TaqI rs731236 A) were enrolled.

RESULTS

Patients with HCC had a higher frequency of ApaI CC genotype (P = 0.027) and bAt[CCA]-haplotype (P = 0.037) as compared to control subjects. There were no differences in BsmI and TaqI polymorphisms between two groups. In patients with chronic hepatitis C, HCC subjects had a higher frequency of ApaI CC genotype and bAt[CCA]-haplotype than those with chronic hepatitis (P = 0.001 and 0.002, respectively) and cirrhosis (P = 0.019 and 0.026, respectively). After adjusting age and sex, logistic regression analysis showed that ApaI CC genotype (odds ratio: 3.02, 95% confident interval: 1.65-5.51) was independently associated with HCC development.

CONCLUSION

VDR ApaI polymorphism plays a role in the development of HCC among chronic hepatitis C patients. Further explorations of this finding and its implications are required.

Interleukin-10-1082 gene polymorphism is associated with papillary thyroid cancer

The etiopathogenesis of thyroid cancer has not been clearly elucidated although the role of chronical inflammation and the imbalance between pro- and anti-inflammatory cytokines may play a role in the etiology. The aim of the present study was to investigate whether cytokine gene polymorphisms are associated with papillary thyroid cancer (PTC), and to evaluate the relationship between genotypes and clinical/laboratory manifestation of PTC. Tumor necrosis factorα (TNFα) G-308A (rs 1800629), interleukin-6 (IL-6) G-174C (rs 1800795) and IL-10 A-1082G (rs 1800896) single nucleotide polymorphisms in DNA from peripheral blood leukocytes of 190 patients with thyroid cancer and 216 healthy controls were investigated by real-time PCR combined with melting curve analysis. There was no notable risk for PTC afflicted by TNFα-308 and IL-6-174 alone. However, IL-10-1082 G allele frequency were higher among PTC patients than healthy controls (p=0.009). The patients with IL-10-1082 GG geotype have twofold increased risk of developing thyroid cancer according to AA genotype (OR 2.07, 95% CI 1.21-3.55). In addition, the concomitant presence of IL-10-1082 G allele (GG+AG genotypes) together with IL-6 -174 GG genotype has a nearly twofold increased risk for thyroid cancer (OR 1.75 with 95% CI 1.00-3.05, p=0.049). We suggest that IL-10-1082 G allele is associated with an increased risk of PTC. The polymorphism of IL-10 gene can improve our knowledge about the pathogenesis of PTC, and could provide to estimate people at the increased risk for PTC.

Vitamin D and Tumor Necrosis Factor-Alpha Receptor Gene Polymorphisms in Various Hepatitis B Clinical Conditions in Turkey

Background

The aim is to define the role of single nucleotide polymorphism on the progress of hepatitis B virus (HBV) infection. We evaluated polymorphisms of TNF-α-308, Vitamin D receptor Apa I and Taq I gene in patients with HBV infection.

Methods

All subjects included were older than 18 years old. Sixty three patients had chronic HBV infection, 61 were HBsAg positive carriers and 59 were positive for anti-HBs and anti-HBc. Gene polymorphisms were evaluated by Amplification Refractory Mutation System PCR. For patients with chronic hepatitis, viral load, ALT levels, and histopathological evaluation of the liver were also compared.

Results

Gender distribution was not different among groups; however, anti-HBs positive patients were significantly older than the other patients. ALT levels and viral load were significantly higher in chronic hepatitis group than the asymptomatic carriers group. Vitamin D receptor Apa I gene and Taq I gene and TNF-α -308 gene variant alleles were not different in all three groups. Variant alleles of three genes were not different in subgroups of chronic hepatitis patients formed according to ALT levels, viral load, histological activity index, and fibrosis score.

Conclusions

Role of single nucleotide polymorphism in clinical status of various HBV infection states was not shown in this study. Considering the other studies performed with this aim, which strengthens the notion that ethnicity is an important factor, future studies with more patients from different ethnic groups may help to clear the role of polymorphisms in the clinical progress of HBV infection.

Cancer risk in immune-mediated inflammatory diseases (IMID)

Inflammation and cancer have a profound yet ambiguous relationship. Inflammation - especially chronic inflammation - has protumorigenic effects, but inflammatory cells also mediate an immune response against the tumor and immunosuppression is known to increase the risk for certain tumors.This article reviews current literature on the role of inflammation in cancer and the cancer risk in immune-mediated inflammatory diseases (IMIDs). We discuss the effect on cancer risk of different drug classes used in the treatment of IMIDs treatment, including biologicals such as tumor necrosis factor (TNF) inhibitors.Overall cancer incidence and mortality risk are similar to the general population in inflammatory bowel disease (IBD), and slightly increased for rheumatoid arthritis and psoriasis, with risk profiles differing for different tumor types. Increased risk for non-melanoma skin cancer is associated with thiopurine treatment in IBD, with the combination of anti-TNF and methotrexate in rheumatoid arthritis and with PUVA, cyclosporine and anti-TNF treatment in psoriasis. Data on the safety of using biologic or immunosuppressant therapy in IMID patients with a history of cancer are scarce.This review provides clinicians with a solid background to help them in making decisions about treatment of immune-mediated diseases in patients with a tumor history.This article is related to another review article in Molecular Cancer: http://www.molecular-cancer.com/content/12/1/86.

Human genetic variation and the risk of hepatocellular carcinoma development

Our understanding of the patho-physiology of hepatocellular carcinoma (HCC) is still much fragmented making difficult the improvement of the clinical outcome for the majority of HCC patients. Discovery of single nucleotide polymorphisms (SNPs) associated with individual susceptibility to HCC may enable the persons at risk to adapt their lifestyle and legitimate implementation by their doctors of surveillance programs facilitating early detection and subsequent management of the disease. To shed light on the influence of human genetic variation on HCC, we conducted a review of the meta-analyses of candidate SNPs and genome wide association studies (GWAS) performed for HCC by search of PubMed and Google Scholar databases. Genetic variations occurring in pathways historically considered as instrumental for liver tumorigenesis (TP53/MDM2, HLA, glutathione-S-transferases/cytochrome P540, TNFα/TGFβ, etc…) are discussed. An immense majority of the data has been produced in Eastern Asia (China, Japan, Korea). These meta-analyses indicate that the TP53, the MDM2 SNP309 G and the GSTT1 null genotype contribute to an increased risk of HCC both in Asians and Caucasians. Significant differences of odds ratios are, however, commonly observed between Eastern-Asians and other populations. Amazingly, GWAS studies performed so far exclusively with HCC patients from Eastern Asia produced drastically different outcomes pointing at unrelated biological pathways. The small magnitude of the risk associated with the genetic variants raises the question of their future utility as markers in clinical practice. An assessment of their impact on tumor progression (vascular invasion, metastases) remains, however, to be done and may prove to be more useful for clinicians. Finally, the evaluation of these variants is not available for various populations of the world and particularly for Subsaharan Africans who are especially affected by HCC.

Obesity, insulin resistance, NASH and hepatocellular carcinoma

Epidemiological and clinical data have clearly demonstrated that non-alcoholic steatohepatitis (NASH) predisposes risk to the development of hepatocellular carcinoma (HCC). NASH is the liver manifestation of metabolic syndrome, which constellates obesity, insulin resistance and dyslipidemia. Although the percentage of patients diagnosed annually with NASH-associated HCC is still relatively low, this number signifies a large population due to the rapidly increasing incidence of obesity and diabetes globally. Fundamental studies on lipid storage, regulation of adipose factors, inflammatory cytokine recruitments and oxidative stress have provided insights into NASH as well as metabolic syndrome. Recent evidence also indicates the significant role of genetic factors in contributing to the pathogenesis of NASH and induced hepatic malignancy. In this review, we attempt to collate current research on NASH biology that lead to our understandings on how metabolic disorders may intersect with cancer development. We also discuss study models that have supported discoveries of molecular and cellular defects, and offered a perspective on therapeutic developments. These studies have collectively increased our knowledge on the complex signaling pathways involved in NASH and cancer, and provided the foundation for improved clinical management of patients with metabolic diseases.

Genomic aspects of NAFLD pathogenesis

Non-alcoholic fatty liver disease (NAFLD) is the most predominant liver disease worldwide and hepatic manifestation of the metabolic syndrome. Its histology spectrum ranges from steatosis, to steatohepatitis (NASH) that can further progress to cirrhosis and hepatocellular carcinoma (HCC). The increasing incidence of NAFLD has contributed to rising numbers of HCC occurrences. NAFLD progression is governed by genetic susceptibility, environmental factors, lifestyle and features of the metabolic syndrome, many of which overlap with HCC. Gene expression profiling and genome wide association studies have identified novel disease pathways and polymorphisms in genes that may be potential biomarkers of NAFLD progression. However, the multifactorial nature of NAFLD and the limited number of sufficiently powered studies are among the current limitations for validated biomarkers of clinical utility. Further studies incorporating the links between circadian regulation and hepatic metabolism might represent an additional direction in the search for predictive biomarkers of liver disease progression and treatment outcomes.

Hepatocellular carcinoma biology

Hepatocellular carcinoma (HCC) is the most common primary hepatic malignancy. Its incidence and prevalence is globally heterogeneous with the highest rates in Southeast Asia and Sub-Saharan Africa. In Western Industry nations, its incidence has significantly increased throughout the previous three decades. Its global heterogeneity is in part a reflection of the global distribution of its risk factors. Its prognosis is dismal with a 5-year survival of 11 %. The only potentially curative treatment is surgical with either resection or orthotopic liver transplantation. However, the majority of HCC patients are diagnosed at an advanced stage at which surgical therapies are not feasible. HCC is considered chemotherapy-resistant-a characteristic thought to be mediated in part through stem-like tumor initiating cells (STICs). Recent studies have provided significant insights in the hepatocarcinogenesis and the molecular signaling pathways of this malignancy resulting in the development of novel, molecular targeted therapies with modest therapeutic benefit. Our growing understanding of the biology of this malignancy will help in the development of novel, molecular-targeted therapies.

The TNF-α -308 Promoter Gene Polymorphism and Chronic HBV Infection

Background and Aims. TNF-α -308 allele promoter polymorphism has been known to be a potential prognostic factor in patients with chronic HBV infection. We tried to determine how TNF-α -308 allele promoter polymorphism would affect the prognosis in patients with chronic HBV infection. Methods. We searched MEDLINE, EMBASE, and reference lists of relevant review articles related to the association between “TNF-α G-308A promoter polymorphism” with “chronic HBV infection”. We only focused on searching -308 locus in published studies. We reviewed 21 original articles about TNF-α -308 allele polymorphism and its effect on prognosis in patients with chronic HBV infection and discussed the results. Results. conflicting results were observed. The results were divided into 3 groups including neutral, negative, and positive associations between TNF-α -308 allele polymorphism and prognosis in patients with chronic HBV infection. We summarized the primary data as a table. Conclusions. Authors concluded that although there is an upward trend in evidence to claim that there is a positive relation between TNF-α G-308A promoter polymorphisms and resolution of chronic HBV infection, due to many biases and limitations observed in reviewed studies, an organized well-designed study is needed for clarifying the real association.

Single nucleotide polymorphisms and risk of hepatocellular carcinoma in cirrhosis

Liver carcinogenesis is a complex and multi-factorial process, in which both environmental and genetic features interfere and contribute to malignant transformation. Patients with cirrhosis are particularly exposed and justify periodical screenings in order to detect the early development of hepatocellular carcinoma (HCC). The risk of HCC is, however, not identical from one patient to another. The identification of host factors that may also play an important role in HCC development may improve our understanding of the implications of the various biological pathways involved in liver carcinogenesis; such progress may as well help refine the selection of patients who could benefit from specific preventative measures or could be given adapted screening policies. Numerous candidate-gene studies have reported associations between single nucleotide polymorphisms (SNPs) and the presence of HCC. Some of these publications unfortunately suffer from major methodological drawbacks because of their case-control, retrospective and monocentric aspect. Prospective cohort studies conducted in large homogeneous populations and comprising a sufficient number of events during follow-up may overcome these pitfalls, but require a long time to be conducted and are still scarce. More recently, the first Genome Wide Association studies (GWAs) have enabled the identification of unsuspected loci that may be involved in various steps implicated in liver tumourigenesis. Taken together, these studies highlight variants that modulate oxidative stress, iron metabolism, inflammatory and immune responses, DNA repair mechanisms or systems involved in cell-cycle regulation as genetic traits susceptible to modify the natural history of cirrhotic patients and partly explain the observed differences in the risk of HCC occurrence. However, large genetic epidemiology studies in the field of cancer diseases have suggested the limited ability of polymorphic traits, alone, to refine individual prognosis. The integration of various panels of genes into clinical scores may in the near future define a "genomic risk prediction" specific to liver cancer developed in cirrhotic patients.

Epidermal growth factor gene polymorphism and risk of hepatocellular carcinoma: a meta-analysis

BACKGROUND

Hepatocarcinogenesis is a complex process that may be influenced by many factors, including polymorphism in the epidermal growth factor (EGF) gene. Previous work suggests an association between the EGF 61*A/G polymorphism (rs4444903) and susceptibility to hepatocellular carcinoma (HCC), but the results have been inconsistent. Therefore, we performed a meta-analysis of several studies covering a large population to address this controversy.

METHODS

PubMed, EMBASE, Google Scholar and the Chinese National Knowledge Infrastructure databases were systematically searched to identify relevant studies. Data were abstracted independently by two reviewers. A meta-analysis was performed to examine the association between EGF 61*A/G polymorphism and susceptibility to HCC. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

Eight studies were chosen in this meta-analysis, involving 1,304 HCC cases (1135 Chinese, 44 Caucasian and 125 mixed) and 2,613 controls (1638 Chinese, 77 Caucasian and 898 mixed). The EGF 61*G allele was significantly associated with increased risk of HCC based on allelic contrast (OR = 1.29, 95% CI = 1.16-1.44, p<0.001), homozygote comparison (OR = 1.79, 95% CI = 1.39-2.29, p<0.001) and a recessive genetic model (OR = 1.34, 95% CI = 1.16-1.54, p<0.001), while patients carrying the EGF 61*A/A genotype had significantly lower risk of HCC than those with the G/A or G/G genotype (A/A vs. G/A+G/G, OR = 0.66, 95% CI = 0.53-0.83, p<0.001).

CONCLUSION

The 61*G polymorphism in EGF is a risk factor for hepatocarcinogenesis while the EGF 61*A allele is a protective factor. Further large and well-designed studies are needed to confirm this conclusion.