Association of cytokine and DNA repair gene polymorphisms with hepatitis B-related hepatocellular carcinoma

Polymorphisms of excision repair gene XPD Lys751Gln and hOGG1 Ser326Cys might not be associated with hepatocellular carcinoma risk: a meta-analysis

The xeroderma pigmentosum group D (XPD) and human 8-oxoguanine glycosylase 1 (hOGG1) genes have been suggested to play an important role in the pathogenesis of hepatocellular carcinoma (HCC). However, the results have been inconsistent. In this study, we performed a meta-analysis to clarify the associations of polymorphisms of XPD and hOGG1 genes with HCC risk. Published literature from PubMed, EMBASE, and Chinese National Knowledge Infrastructure were retrieved. Pooled odds ratio (OR) with 95 % confidence interval (CI) was calculated using a fixed- or random-effects model. Seven studies (1,955 HCC cases and 2,023 controls) for XPD Lys751Gln polymorphism and six studies (1,470 HCC cases and 1,541 controls) for hOGG1 Ser326Cys polymorphism were included in the final meta-analysis. For XPD Lys751Gln polymorphism, no significant association was found under all genetic models (Gln/Gln vs Lys/Lys OR = 1.09, 95 % CI = 0.28-4.18; Gln/Lys vs Lys/Lys OR = 1.41, 95 % CI = 0.81-2.44; dominant model OR = 1.40, 95 % CI = 0.77-2.57; recessive model OR = 1.02, 95 % CI = 0.33-3.23). For hOGG1 Ser326Cys polymorphism, there was a significant association of this polymorphism with HCC risk under heterogeneous codominant model (OR = 1.38, 95 % CI = 1.01-1.88) and dominant model (OR = 1.57, 95 % CI = 1.14-2.16). The sensitivity analysis indicated that the significant association between hOGG1 Ser326Cys polymorphism and HCC risk was not robust. The present meta-analysis has limited evidence to support the association of XPD Lys751Gln and hOGG1 Ser326Cys polymorphisms with HCC risk. Further, large-scale studies with the consideration for gene-gene/gene-environment interactions should be conducted to investigate the association.

Interleukin-1 polymorphism and expression in hepatitis B virus-mediated disease outcome in India

The present study evaluated any possible association among Interleukin-1-beta (IL-1B)-511 and IL-1 receptor antagonist (IL-1RN) variable number tandem-repeat (VNTR) genotypes, haplotypes, and IL-1B expression with risk for hepatitis B virus-related hepatocellular carcinoma (HBV-HCC) development in India. For this, 406 subjects (153 controls, 67 inactive HBV-carriers, 65 patients with chronic-active HBV, 62 HBV-cirrhotics, and 59 subjects with HBV-HCC) were enrolled in the study. Polymerase chain reaction (PCR)-restriction fragment length polymorphism, reverse transcriptase-PCR, and enzyme-linked immunosorbent assay methods were used for assessing polymorphism, mRNA, and protein levels, respectively, of IL-1. The study revealed no significant association of IL-1B(-511) CT and TT genotypes, while a significant positive association of the IL-1RN (VNTR) 1/2 genotype with HCC development, among controls and carriers. Besides, 2/2 genotypes acted as a potential risk factor for hepatitis and subsequent cirrhosis development, among the same groups. Furthermore, the IL-1 haplotypes 2 and 3 were found to be significant protective factors for hepatitis and subsequent HCC development, among controls. However, haplotype 4 shared a significant negative association with hepatitis only. Moreover, proinflammatory IL-1B levels significantly and steadily elevated with the disease progression to HCC, as compared to controls. These preliminary findings indicate a key role of IL-1 in the HBV-mediated disease chronicity, in the Indian population.

MLH1 polymorphisms and cancer risk: a meta-analysis based on 33 case-control studies

OBJECTIVE

Cumulative evidence suggests that MLH1, the key component in the mismatch pathway, plays an important role in human cancers. Two potential functional polymorphisms (-93G>A and I219V) of MLH1 have been implicated in cancer risk. The aim of this meta-analysis was to summarize the evidence for associations.

METHODS

Eligible studies were identified by searching the electronic literature PubMed, ScienceDirect and Embase databases for relevant reports and bibliographies. Studies were included if of case-control design investigating MLH1 polymorphisms (-93G>A and I219V) and cancer risk with sufficient raw data for analysis. Odds ratios (OR) and 95% confidence intervals (95% CI) were used to evaluate the strength of associations.

RESULTS

Our meta-analysis from 33 published case-control studies showed the variant A allele of -93G>A polymorphism to be associated with increased risk in all genetic models (AA vs. GG: OR = 1.22, 95% CI: 1.03-1.44), especially among non-Asians (AA vs. GG: OR = 1.28, 95% CI: 1.04-1.58). For the I219V polymorphism, however, there was no main effect associated with overall cancer risk in any genetic model.

CONCLUSIONS

The meta-analysis suggested that the MLH1 -93G>A polymorphism may be a biomarker of cancer susceptibility. Large sample association studies and assessment of gene-to-gene as well as gene-to-environment interactions are required to confirm these findings.

A meta-analysis of the relationship between glutathione S-transferases gene polymorphism and hepatocellular carcinoma in Asian population

The results from the published studies on the association between glutathione S-transferases (GST) gene polymorphism and hepatocellular carcinoma (HCC) in Asian population are still conflicting. GSTM1, GSTT1 and GSTP1 are the mainly mutant sites reported at present. This meta-analysis was performed to evaluate the relationship between GST gene polymorphism and HCC risk in Asians. Association studies were identified from the databases of PubMed, Embase, Cochrane Library and CBM-disc (China Biological Medicine Database) on February 1, 2012, and eligible investigations were synthesized using meta-analysis method. Results were expressed with odds ratios (OR) for dichotomous data, and 95 % confidence intervals (CI) were also calculated. Twenty-five investigations were identified for the analysis of association between polymorphic deletion of GSTM1 and HCC, consisting of 3,547 patients with HCC and 6,132 controls. There was a marked association between GSTM1 null genotype and HCC susceptibility (OR 1.48, 95 % CI 1.19-1.85, P = 0.0004). GSTM1 null genotype was associated with HCC risk in Chinese. Furthermore, null genotype of GSTT1 was associated with HCC susceptibility in Asians. For the GSTM1-GSTT1 interaction analysis, the dual null genotype of GSTM1/GSTT1 was significantly associated with HCC susceptibility in Asian population. However, GSTP1 ile105 val gene polymorphism was not associated with HCC risk in Asian population. In conclusion, GSTM1/GSTT1 null genotype is associated with the HCC susceptibility. However, GSTP1 gene polymorphism is not associated with HCC risk.

Polymorphisms of DNA repair gene XRCC1 and hepatocellular carcinoma risk among East Asians: a meta-analysis

Association studies on the X-ray repair cross-complementing group 1 (XRCC1) polymorphisms (Arg194Trp, Arg280His, and Arg399Gln) in hepatocellular carcinoma (HCC) have shown conflicting results. The aim of this study was to quantitatively summarize the evidence for such a relationship. Published literatures from PubMed, Embase, CNKI, and Chinese Biomedicine Database were retrieved. Pooled odds ratio (OR) with 95 % confidence interval (CI) was calculated using fixed- or random-effects model. Thirteen studies including 3,011 HCC cases and 3,619 controls were included in the meta-analysis of the association between XRCC1 Arg399Gln polymorphism and HCC risk. The results indicated that Arg399Gln polymorphism was significantly associated with risk of HCC in a codominant model (Gln/Gln vs. Arg/Arg, OR = 1.32, 95 % CI = 1.08-1.61; Arg/Gln vs. Arg/Arg, OR = 1.41, 95 % CI = 1.12-1.80) and a dominant model (Gln/Gln + Arg/Gln vs. Arg/Arg, OR = 1.39, 95 % CI = 1.15-1.69), but not in a recessive model (Gln/Gln vs. Arg/Gln + Arg/Arg, OR = 1.13, 95 % CI = 0.95-1.35). Limiting the analysis to the studies within Hardy-Weinberg equilibrium, the results were persistent and robust. When stratifying for region and source of controls, persistent results were observed in any subgroup. No evidence of association of Arg194Trp (980 HCC cases and 966 controls) and Arg280His (1,200 HCC cases and 1,236 controls) with HCC risk was found. No publication bias was found in the present study. The results from the present meta-analysis indicated that the Arg399Gln polymorphisms of XRCC1 may be a genetic susceptibility for HCC in the East Asian population. Further, large and well-designed studies are needed to confirm this conclusion.

Multiple cytokine expression profiles reveal immune-based differences in occult hepatitis B genotype H-infected Mexican Nahua patients

A high prevalence of occult hepatitis B (OHB) genotype H infections has been observed in the native Mexican Nahua population. In addition, a low incidence of hepatitis B virus (HBV)-associated hepatocellular carcinoma has been described in Mexico. The immune response to infection among OHB-infected patients has been poorly evaluated in vivo. Therefore, we assessed the expression profiles of 23 cytokines in OHB genotype H-infected Nahua patients. A total of 41 sera samples from natives of the Nahua community were retrospectively analysed. Based on their HBV antibody profiles, patients were stratified into two groups: OHB patients (n = 21) and patients that had recovered from HBV infection (n = 20). Herein, we report distinctive cytokines profiles in OHB-infected individuals. Compared to healthy controls (n = 20) and patients who resolved HBV infection, OHB-infected patients displayed an increase in interleukin (IL)-2 secretion in addition to a characteristic inflammation profile (decrease in IL-8 and tumour necrosis factor-alpha levels and increased levels of tumour growth factor-beta). IL-15 and interferon-gamma levels were reduced in OHB-infected individuals when compared to those patients who resolved HBV infection. In contrast, OHB patients showed an increase in monocyte chemoattractant protein (MCP)-1 and MCP-2 compared to healthy controls and patients who resolved HBV infection. These findings suggest that cytokine expression can influence the severity of OHB disease and could lead to new investigation into the treatment of liver and other infectious diseases.

Host genetic factors in hepatitis B infection, liver cancer and vaccination response: a review with a focus on Africa

The disease burden due to hepatitis B virus (HBV) infection remains significant; 350 million people are infected world-wide, and around half a million deaths each year are due to HBV-related liver disease and hepatocellular carcinoma (HCC). Infant immunisation against infection was introduced in the early 1980s, the vaccine is routinely administered across regions where the disease is endemic and has been shown to be safe and effective. However, the large number of older individuals with persistent infection means that disease will not be reduced significantly for several decades. Furthermore, failure to respond to the vaccination has been observed in about 5% of vaccinees and to date we have limited information on the durability of vaccine protection against infection. Hepatitis B infection and disease pathogenesis are known to be influenced by a number of factors including host genetics factors. This review aims to give an overview of the role of genetic variation in persistent HBV infection and the development of liver disease including HCC. Vaccine-induced immunity is, at least in part, heritable and we also discuss findings on the genetic control of responses to HBV vaccination. The epidemiology of HBV infection differs by world region, as does the genetic makeup of individuals originating from different regions. This review focuses on the situation in Africa, where hepatitis B is highly endemic.

Hepatocellular carcinoma: towards personalized medicine

Over the past several years, the success of genome-wide association studies (GWAS) and pharmacogenomics has gradually begun to enable personalized medicine in some fields. In the field of liver diseases, host genetic factors are now very useful in clinical practice for predicting treatment outcome and adverse reactions for pegylated interferon plus ribavirin combination therapy against chronic hepatitis C virus (HCV) infection. Recently, three virus-related hepatocellular carcinoma (HCC) GWAS were reported from Asia. One study examined hepatitis B virus-related HCC in China, where hepatitis B is very prevalent, and the other two examined HCV-related HCC in Japan. We identified a common variant in the DEPDC5 locus associated with HCV-related HCC, and another group identified an association involving the MICA locus. In this review, we compare the results of these GWAS and earlier candidate gene studies. Further research is needed to determine the role of these single nucleotide polymorphisms on HCC risk, but identification of these markers could make it possible to assess the magnitude of the risk of cancer based on each patient's genetic background. Consideration of the genetic background of the patients will likely play a role in personalized medicine for HCC, and understanding the mechanism underlying the association could suggest novel promising therapeutic targets in the future.

The significance of Exonuclease 1 K589E polymorphism on hepatocellular carcinoma susceptibility in the Turkish population: a case-control study

Exonuclease 1 (Exo 1) is an important nuclease involved in mismatch repair system that contributes to maintain genomic stability, to modulate DNA recombination, and to mediate cell cycle arrest. A guanine (G)/adenine (A) common single nucleotide polymorphism at first position of codon 589 in Exo 1 gene determines a glutamic acid (Glu, E) to lysine (Lys, K) (K589E) aminoacidic substitution which may alter cancer risk by influencing the activity of Exo 1 protein. Exo 1 K589E polymorphism has been studied in various cancers, but its association with hepatocellular carcinoma (HCC) has yet to be investigated. To determine the association of the Exo 1 K589E polymorphism with the risk of HCC development in a Turkish population, a hospital-based case-control study was designed consisting of 224 subjects with HCC and 224 cancer-free control subjects matched for age, gender, smoking and alcohol status. The genotype frequency of the Exo 1 K589E polymorphism was determined by using a polymerase chain reaction-restriction fragment length polymorphism assay. Our data shows that the Lys/Lys genotype of the Exo 1 K589E polymorphism is associated with increased risk of HCC development in this Turkish population [odds ratio (OR) = 2.15, 95% confidence interval (CI): 1.13-4.09, P = 0.02]. Furthermore, according to stratified analysis, a significant association was observed between the homozygote Lys/Lys genotype and HCC risk in the subgroups of male gender (OR = 2.67, 95% CI: 1.27-5.61, P = 0.009) and patients with non-viral-related HCC (OR = 3.14, 95% CI: 1.09-8.99, P = 0.03). Because our results suggest for the first time that the Lys/Lys homozygote genotype of Exo 1 K589E polymorphism may be a genetic susceptibility factor for HCC in the Turkish population, further independent studies are required to validate our findings in a larger series, as well as in patients of different ethnic origins.

Genome-wide association study of hepatocellular carcinoma in Southern Chinese patients with chronic hepatitis B virus infection

One of the most relevant risk factors for hepatocellular carcinoma (HCC) development is chronic hepatitis B virus (HBV) infection, but only a fraction of chronic HBV carriers develop HCC, indicating that complex interactions among viral, environmental and genetic factors lead to HCC in HBV-infected patients. So far, host genetic factors have incompletely been characterized. Therefore, we performed a genome-wide association (GWA) study in a Southern Chinese cohort consisting of 95 HBV-infected HCC patients (cases) and 97 HBV-infected patients without HCC (controls) using the Illumina Human610-Quad BeadChips. The top single nucleotide polymorphisms (SNPs) were then validated in an independent cohort of 500 cases and 728 controls. 4 SNPs (rs12682266, rs7821974, rs2275959, rs1573266) at chromosome 8p12 showed consistent association in both the GWA and replication phases (OR(combined) = 1.31-1.39; p(combined) = 2.71 × 10(-5)-5.19 × 10(-4); PAR(combined) = 26-31%). We found a 2.3-kb expressed sequence tag (EST) in the region using in-silico data mining and verified the existence of the full-length EST experimentally. The expression level of the EST was significantly reduced in human HCC tumors in comparison to the corresponding non-tumorous liver tissues (P<0.001). Results from sequence analysis and in-vitro protein translation study suggest that the transcript might function as a long non-coding RNA. In summary, our study suggests that variations at chromosome 8p12 may promote HCC in patients with HBV. Further functional studies of this region may help understand HBV-associated hepatocarcinogenesis.

Hepatocellular carcinoma and other liver disease among Greenlanders chronically infected with hepatitis B virus: a population-based study

BACKGROUND

In Greenland, the prevalence of hepatitis B surface antigen carriers, reflecting chronic hepatitis B virus (HBV) infection, is 5%-10%. However, the incidence of cirrhosis and hepatocellular carcinoma in this population has been reported to be low. We investigated this discrepancy in a large population-based cohort study.

METHODS

In total, 8879 Greenlanders (16% of the population) were recruited for population-based surveys performed from May 5 to July 7, 1987, and from November 1 to November 21, 1998, with follow-up until March 31, 2010. HBV status was based on serological testing, supplemented by data from all available HBV registries in Greenland to determine changes in HBV status over time. Information on morbidity and mortality was obtained from the Patient Discharge Registry, the Cancer Registry, and the Central Registration System. Sex, age, ethnicity, and period-adjusted incidence rate ratios (IRRs) were estimated using Poisson regression. World standardized rates were derived from these and World Health Organization data.

RESULTS

The 650 chronically HBV-infected persons had higher rates of hepatocellular carcinoma (adjusted IRR = 8.70; 95% CI = 2.06 to 36.7), liver disease (adjusted IRR = 5.73, 95% CI = 3.52 to 9.34), and all-cause mortality (adjusted IRR = 1.47; 95% CI = 1.21 to 1.79) than the 5160 HBV-negative persons. However, the world standardized incidence rates of hepatocellular carcinoma (38.5 cancers per 100 000 person-years) and cirrhosis (24 cases per 100 000 person-years) among chronically HBV-infected persons were low compared with results from population-based studies from countries with low, intermediate, and high rates of endemic HBV infection.

CONCLUSION

The relatively low incidence of hepatocellular carcinoma and other HBV-related morbidity among chronic HBV-infected persons in Greenland suggest a more benign course of HBV among the Greenlandic Inuit than in populations in other parts of the world.

Factors predicting occurrence and prognosis of hepatitis-B-virus-related hepatocellular carcinoma

Primary liver cancer is an important cause of cancer death, and hepatocellular carcinoma (HCC) accounts for 70%-85% of total liver cancer worldwide. Chronic hepatitis B virus (HBV) infection contributes to > 75% of HCC cases. High serum viral load is the most reliable indicator of viral replication in predicting development of HCC. HBV genotype C is closely associated with HCC in cirrhotic patients aged > 50 years, whereas genotype B is associated with development of HCC in non-cirrhotic young patients and postoperative relapse of HCC. Different HBV subgenotypes have distinct patterns of mutations, which are clearly associated with increased risk of HCC. Mutations accumulate during chronic HBV infection and predict occurrence of HCC. Chronic inflammation leads to increased frequency of viral mutation via cellular cytidine deaminase induction. Mutations are negatively selected by host immunity, whereas some immuno-escaped HBV mutants are active in hepatocarcinogenesis. Inflammatory pathways contribute to the inflammation-necrosis-regeneration process, ultimately HCC. Their hallmark molecules can predict malignancy in HBV-infected subjects. Continuing inflammation is involved in hepatocarcinogenesis and closely related to recurrence and metastasis. HBV load, genotype C, viral mutations and expression of inflammatory molecules in HBV-related HCC tissues are significantly associated with poor prognosis. Imbalance between intratumoral CD8⁺ T cells and regulatory T cells or Th1 and Th2 cytokines in peritumoral tissues can predict prognosis of HBV-related HCC. These factors are important for developing active prevention and surveillance of HBV-infected subjects who are more likely to develop HCC, or for tailoring suitable treatment to improve survival or postpone postoperative recurrence of 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.

Association of TNF-alpha genetic polymorphisms with hepatocellular carcinoma susceptibility: a case-control study in a Han Chinese population

The single nucleotide polymorphisms (SNPs) within the tumor necrosis factor-a (TNF-a) gene promoter region have been reported to be associated with susceptibility to various types of cancers. A case-control study (126 hepatocellular carcinoma [HCC] patients and 126 normal controls) was conducted to elucidate their possible association with the risk of hepatitis B virus (HBV)-related HCC in a Han Chinese population. TNF-alpha polymorphisms -1031T/C, -863C/A, -857C/T, -308G/A, and -238G/A were genotyped by polymerase chain reaction (PCR) and direct DNA sequencing. Disease associations were analyzed by the chi-square test or Fisher's exact test. When analyzed by overall groups, no significant differences in genotype and allele distributions were observed between the control and cases. However, stratified analysis according to sex showed that the frequency of the homozygous C allele of the -857 polymorphism was lower in female cases than in female controls (62.9% vs. 88.9%, p=0.026). In addition, further haplotype analysis revealed that the TCCGA (-1031/-863/-857/-308/-238) was more frequent in controls than cases (p=0.018; odds ratio = 0.266; 95% confidence interval, 0.083-0.857). These results indicated that the TNF-alpha-857C/T polymorphism may modify HBV-related HCC risk among women, and the haplotype TCCGA (-1031/-863/-857/-308/-238) may account for a decreased susceptibility to HCC development in the Han Chinese population. Additional studies in patients with different ethnic backgrounds are needed to validate these finding and to further explore the genetic pathogenesis of HBV-related HCC.

GST polymorphisms are associated with hepatocellular carcinoma risk in Chinese population

AIM: To investigate the association between GSTM1 and GSTT1 polymorphisms and the risk of hepatocellular carcinoma (HCC) in Chinese population.

METHODS: Literature databases including PubMed, ISI web of science and other databases were searched. Pooled odds ratio (OR) and 95% CI were calculated using random- or fixed- effects model. Subgroup analysis and sensitivity analysis were also performed.

RESULTS: Nineteen studies of GSTM1 (2660 cases and 4017 controls) and 16 studies of GSTT1 (2410 cases and 3669 controls) were included. The GSTM1/GSTT1 null genotypes were associated with increased risk of HCC in Chinese population (for GSTM1, OR = 1.487, 95% CI: 1.159 to 1.908, P = 0.002; for GSTT1, OR = 1.510, 95% CI: 1.236 to 1.845, P = 0.000). No publication bias was detected. In subgroup analysis, glutathione S-transferases polymorphisms were significantly associated with HCC risk among the subjects living in high-incidence areas, but not among the subjects living in low-incidence areas.

CONCLUSION: The present meta-analysis suggests that GSTM1/GSTT1 null genotypes are associated with increased risk of HCC in Chinese population.

The association between MLH1 -93 G>A polymorphism of DNA mismatch repair and cancer susceptibility: a meta-analysis

DNA mismatch repair, known as a fundamentally biological pathway, plays key roles in maintaining genomic stability, eliminating mismatch bases and preventing both mutagenesis in the short term and cancerogenesis in the long term. Polymorphisms of MLH1 in individuals may have an effect on the DNA repair capacity and therefore on cancer risk. Recently, emerging studies have been done to evaluate the association between MLH1 -93 G/A polymorphism and cancer risk in diverse populations. However, the results remain conflicting rather than conclusive. In this meta-analysis, we assessed reported studies of association between the MLH1 -93 G/A polymorphism and cancer risk including 13 691 cancer cases and 14 068 controls from 17 published studies. A borderline significant association between the MLH1 -93 G/A polymorphism and cancer risk was observed in overall analysis [heterozygote: odds ratio (OR) = 1.15; 95% confidence interval (CI) 1.05-1.26; homozygote: OR = 1.21; 95% CI, 1.04-1.40; dominant model: OR = 1.13; 95% CI 1.01-1.26; recessive model: OR = 1.21; 95% CI 1.07-1.35, respectively]. In subgroup analysis by ethnicity, significantly increased risks were found in Asian population and mixed population but not in Caucasian population. After stratified analysis according to the quality of literature, increased cancer risks were observed in the studies of lower quality but not in the studies of higher quality. Similarly, elevated cancer risks were observed in hospital-based studies but not in population-based studies. These findings showed no persuasive evidence that MLH1 -93 G/A polymorphism was associated with an increased risk of cancer. On the conservative standpoint, well-designed population-based studies with larger sample size in different ethnic groups should be performed to further confirm these results.

XRCC1 genetic polymorphism Arg399Gln and hepatocellular carcinoma risk: a meta-analysis

BACKGROUND

Studies investigating the association between X-ray repair cross-complementing group 1 (XRCC1) genetic polymorphism Arg399Gln and hepatocellular carcinoma (HCC) risk report conflicting results. The aim of this study was to quantitatively summarize the evidence for such a relationship.

METHODS

Two investigators independently searched the Medline, Embase, CNKI and Chinese Biomedicine Database. Summary odds ratios (ORs) and 95% confidence intervals (95% CIs) for XRCC1 polymorphism 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. The pooled ORs were performed for a codominant model (Gln/Gln vs. Arg/Arg, Arg/Gln vs. Arg/Arg), a dominant model (Gln/Gln+Arg/Gln vs. Arg/Arg) and a recessive model (Gln/Gln vs. Arg/Gln+Arg/Arg).

RESULTS

This meta-analysis included 11 case-control studies, which included 2208 HCC cases and 3265 controls. Overall, the variant genotypes (Gln/Gln and Arg/Gln) of Arg399Gln were not associated with HCC risk when compared with the wild-type Arg/Arg homozygote (Gln/Gln vs. Arg/Arg, OR=1.01, 95% CI=0.79-1.28; Arg/Gln vs. Arg/Arg, OR=1.09, 95% CI=0.81-1.45). Similarly, no associations were found in the dominant and recessive models (dominant model, OR=1.12, 95% CI=0.85-1.47; recessive model, OR=0.99, 95% CI=0.79-1.25). Limiting the analysis to the studies within Hardy-Weinberg equilibrium, the results were persistent and robust. When stratifying for ethnicity, country/region and source of controls, no evidence of a significant association was observed in any subgroup. No publication bias was found in the present study.

CONCLUSION

No association is found between the XRCC1 polymorphism Arg399Gln and the risk of HCC.

Interleukin 1 beta (IL1B) promoter polymorphism and cancer risk: evidence from 47 published studies

Interleukin 1β (IL-1B) is a pro-inflammatory cytokine against infection, playing an important role in the pathogenesis of cancers. The -31T/C polymorphism of the interleukin 1β gene (IL1B) has been implicated in cancer risk through its influence on the IL1B transcription. However, results from studies are conflicting. To clarify the association, a meta-analysis was performed for 11 125 cases and 14 415 controls from 47 published case-control studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the association. No significant associations were observed for total cancer from all the comparisons. Through the stratified analyses, there was a statistically significant decreased risk of hepatocellular cancer in carriers of the C allele than non-carriers (CC versus TT: OR = 0.87, 95% CI: 0.77-0.98, P(heterogeneity) = 0.103; TC versus TT: OR = 0.77, 95% CI: 0.62-0.95, P(heterogeneity) = 0.734; TC + CC versus TT: OR = 0.74, 95% CI: 0.61-0.91, P(heterogeneity) = 0.472). Similarly, decreased risk was observed for gastric cancer of the C/C genotype compared with the T/T genotype (OR = 0.87, 95% CI: 0.77-0.98, P(heterogeneity) = 0.103). Using the recessive model, a significantly decreased risk was observed for gastric cancer (OR = 0.88, 95% CI: 0.80-0.97, P(heterogeneity) = 0.158), European population (OR = 0.84, 95% CI: 0.73-0.97, P(heterogeneity) = 0.070) and positive infection-matched studies (OR = 0.75, 95% CI: 0.60-0.94, P(heterogeneity) = 0.220); however, an increased risk was found for breast cancer (OR = 1.34, 95% CI: 1.18-1.61, P(heterogeneity) = 0.116). Although some modest bias could not be eliminated, this meta-analysis suggests that the IL1B -31C allele is a low-penetrance protective factor for the development of cancer, in particular for that associated with infection.

Tumor necrosis factor alpha 308 G/A polymorphism and hepatocellular carcinoma risk in a Chinese population

BACKGROUND

The genetic basis of susceptibility to hepatocellular carcinoma (HCC) is poorly understood. Tumor necrosis factor alpha (TNF-α) is a cytokine that may act as an endogenous tumor promoter. The association between TNF-α 308 G/A polymorphism and HCC risk remains unclear.

AIM

The aim of this study was to investigate the association between TNF-α 308 G/A polymorphism and HCC risk in a Chinese population.

METHODS

The study population consisted of 88 patients with documented HCC and 88 healthy controls. The gene polymorphism of TNF-α was analyzed by polymerase chain reaction-restriction fragment length polymorphism assay.

RESULTS

HCC patients had a significantly lower frequency GG (odds ratio=0.36; 95% confidence interval=0.13, 0.94; p=0.04) and G allele (odds ratio=0.58; 95% confidence interval=0.37, 0.90; p=0.01) than healthy controls. When stratifying for tumor size and cirrhosis, no statistically significant results were found.

CONCLUSION

This study suggested that TNF-α -308GG and G allele were associated with a modest decrease in the risk of HCC in Chinese population.

Recent advances in the research of hepatitis B virus-related hepatocellular carcinoma: epidemiologic and molecular biological aspects

Hepatocellular carcinoma (HCC) is one of the commonest cancers worldwide, and more than half of HCC patients are attributable to persistent hepatitis B virus (HBV) infections. The best and cheapest way to prevent HBV-related HCC is the implementation of universal hepatitis B vaccination program, by which the incidence rates of childhood HCC have been reduced in several countries, including Taiwan. However, there are still hundreds of millions of HBV carriers in the world that remain a global health challenge. In the past decade, several hepatitis B viral factors such as serum HBV DNA level, genotype, and naturally occurring mutants have already been identified to influence liver disease progression and HCC development in HBV carriers. Several easy-to-use scoring systems based on clinical and viral characteristics are developed to predict HCC risk in HBV carriers and may facilitate the communication between practicing physicians and patients in clinical practice. In addition, the role of nonviral factors in HBV-related HCC has also been increasingly recognized. On the basis of these emerging data, it is recommended that HBV carriers should be screened and monitored to identify those who have a higher risk of liver disease progression and require antiviral treatments. Regarding the molecular carcinogenesis of HCC development, despite some progress in the research of cell biology of HCC in the past decade, aberrant pathways involved in maintaining HCC phenotypes have not been completely elucidated yet. In the future, through comprehensive and integrated approaches to analyze the genomes of human HCC, novel target genes or pathways critically involved in hepatocarcinogenesis may hopefully be identified.

Combined effect of pro- and anti-inflammatory cytokine gene polymorphisms on susceptibility to liver cirrhosis in Tunisian HCV-infected patients

PURPOSE

Chronic hepatitis C progression is commonly attributed to the continuous activation of the immune response with an increased production of pro-inflammatory cytokines, leading to fibrosis and ultimately to cirrhosis. On the contrary, anti-inflammatory cytokines, mainly interleukin (IL)-10 have a modulatory effect on hepatic fibrogenesis. The association between individual polymorphisms within cytokine genes and hepatitis C outcome is often weak and non-informative. Interestingly, it has been demonstrated that a combination of specific genotypes may be a more significant and powerful approach for predicting disease risk.

AIM

This study is aimed at investigating the combined effect of single nucleotide polymorphism (SNP) in IL-18 (-607C/A, -137G/C), interferon (IFN)-γ (+874T/A) and IL-10 (-1082G/A) genes on cirrhosis risk in HCV-infected patients.

METHODS

Seventy-seven chronic hepatitis C Tunisian subjects were included in this study. The patients were divided into two groups: the first included 31 non-cirrhotic patients, and the second included 46 liver cirrhosis patients. IL-18 genotyping was performed using the PCR amplification and the restriction fragment length polymorphism analysis (RFLP). IFN-γ and IL-10 polymorphisms were analyzed using the allele-specific PCR (AS-PCR).

RESULTS

The combined high-risk genotype (IL-18 -607C/*, IL-18 -137G/*, IFN-γ +874T/*, IL-10 -1082A/A) frequency was compared between patients with and those without cirrhosis. Individuals were classified according the number of high-risk genotypes as follows: (0-2), patients with at most two high-risk genotypes; (3-4), patients with at least three of the high-risk genotypes. The logistic regression analysis showed that patients harboring 3-4 putative high-risk genotypes have a fivefold higher risk for developing cirrhosis in comparison to those harboring at most two high-risk genotypes (OR = 5.19; 95% CI = 1.49-18.05; p = 0.009).

CONCLUSION

Our study showed that the co-inheritance of IL-18, IFN-γ and IL-10 specific high-risk genotypes is associated with a greater risk for liver cirrhosis.

Evaluation of the association studies of single nucleotide polymorphisms and hepatocellular carcinoma: a systematic review

PURPOSE

For decades of years, hundreds of candidate gene-based association studies explored the relationship between single nucleotide polymorphisms (SNPs) and hepatocellular carcinoma (HCC). There was no systematic review summarized the results of these association studies of candidate SNPs and HCC to date. In order to summarize the results of the association studies, we conducted a concise systematic review.

METHODS

By searching Pubmed database before October 2010, we reviewed all the association studies about candidate SNPs and HCC. If the eligible study number on a given SNP was more than three, we conducted a meta-analysis. We reported here only the overall positive-association results with statistical significance and evaluated the reliability of the associations by using false-positive report probability (FPRP) analysis and the Venice guidelines on genetic epidemiology studies.

RESULTS

Six SNPs of five genes (rs1800562 of HFE, rs17868323 and rs11692021 of UGT1A7, rs2279744 of MDM2, rs1143627 of IL-1B, and rs4880 of MnSOD) showed overall significant associations with HCC. The eligible number of the studies varied from three to nine. Two SNPs (rs1800562 of HFE and rs2279744 of MDM2) passed the FPRP threshold (FPRP < 0.20). According to the Venice guidelines, the associations between the two SNPs (rs1800562 and rs2279744) and HCC were of moderate evidence.

CONCLUSIONS

Two SNPs (rs1800562 of HFE and rs2279744 of MDM2) were associated with HCC with moderate epidemiological evidence and deserve further study and additional biological and clinical assessment.

The TNF-α, IL-1B and IL-10 polymorphisms and risk for hepatocellular carcinoma: a meta-analysis

OBJECTIVE

TNF-α-308 G/A, TNF-α-238 G/A, IL-1B-31 T/C, IL-1B-511 C/T, and IL-10-1082 G/A polymorphisms have been reported to influence the risk for hepatocellular carcinoma (HCC) in many studies; however, the results still remains controversial and ambiguous. The aim of this study was to determine more precise estimations for the relationship between TNF-α, IL-1B, and IL-10 polymorphisms and the risk for HCC by meta-analysis.

METHODS

Electronic searches for all publications were conducted on associations between these variants and HCC in several databases through September 2010. Odds ratios (OR) with 95% confidence intervals (95% CI) were calculated to estimate the strength of this association in a random-effect model. Twenty studies were identified, involving 2,763 HCC patients and 4,152 controls.

RESULTS

This meta-analysis showed significant association between TNF-α-308 polymorphism and HCC (AA + GA vs. GG: OR = 1.74, 95% CI = 1.12-2.72). In Caucasian and Asian subgroups, OR values (95% CI) were 1.49 (0.58-3.82) and 1.84 (1.06-3.20), respectively. While the ORs for TNF-α-238 G/A, IL-1B-31 T/C, -511 C/T and IL-10-1082 G/A polymorphisms and HCC were 1.37 (0.95-2.00), 1.24 (0.99-1.55), 1.12 (0.66-1.88) and 0.91 (0.74-1.12), respectively. The sensitivity analysis further strengthened the overall strong positive correlations. No publication bias was observed in this study.

CONCLUSIONS

TNF-α-308 G/A polymorphism is assumed to confer a higher risk for HCC, especially in Asian population. TNF-α-238 G/A, IL-1B-31 T/C, -511 C/T, and IL-10-1082 G/A polymorphisms were not detected to be related to the risk for HCC.

Tumour necrosis factor-alpha polymorphisms and hepatocellular carcinoma: a meta-analysis

The genetic basis of susceptibility to hepatocellular carcinoma (HCC) is poorly understood. To summarize the quantitative association between polymorphisms of the tumour necrosis factor-alpha (TNFA) gene and HCC, a meta-analysis of relevant studies was performed. Ten case-control studies involving 1421 HCC cases were identified from the Medline, Embase and Current Contents databases. Combined results based on all studies showed that patients with HCC had a significantly lower frequency of the TNFA gene polymorphism -308GG than healthy controls. When stratifying for race, results were similar among Asians and Caucasians. When comparing with hepatitis B virus infection cases, no statistical association was found. This meta-analysis suggests that TNFA -308GG gene polymorphism is associated with a modest decrease in the risk of HCC.

Null genotypes of GSTM1 and GSTT1 contribute to hepatocellular carcinoma risk: evidence from an updated meta-analysis

BACKGROUND & AIMS

Studies investigating the associations between glutathione S-transferase (GST) genetic polymorphisms and hepatocellular carcinoma (HCC) risk have reported controversial results. Thus, a meta-analysis was performed to clarify the effects of GSTM1 and GSTT1 polymorphisms on HCC risk.

METHODS

We identified 132 relevant records through a literature search up to November 22, 2009, and 24 individual case-control studies from 23 publications were finally included, involving a total of 3349 HCC cases and 5609 controls. Subgroup analyses were performed by ethnicity, or by area according to the incidence rate and hepatitis virus status.

RESULTS

Analyses of total relevant studies showed an increased HCC risk was significantly associated with null genotypes of GSTM1 (OR=1.26, 95% CI 1.03-1.54, p(OR)=0.027) and GSTT1 (OR=1.28, 95% CI 1.09-1.51, p(OR)=0.002). In addition, the GSTM1-GSTT1 interaction analysis showed that the dual null genotype of GSTM1/GSTT1 was significantly associated with increased HCC risk (OR=1.89, 95% CI 1.38-2.60, p(OR)<0.001). Subgroup analyses showed that the associations above were still statistically significant in Asians (p(GSTM1)=0.017, p(GSTT1)=0.001, p(Dual null genotype)<0.001), high-rate areas (p(GSTM1)=0.012, p(GSTT1)=0.006, p(Dual null genotype)<0.001), and HBV-dominant areas (p(GSTM1)=0.003, p(GSTT 1)=0.003, p(Dual null genotype)<0.001).

CONCLUSIONS

This meta-analysis suggests null genotypes of GSTM1 and GSTT1 are both associated with increased HCC risk in Asians, and individuals with the dual null genotype of GSTM1/GSTT1 are particularly susceptible to developing HCC.

Clinical relevance and public health significance of hepatitis B virus genomic variations

Ten hepatitis B virus (HBV) genotypes (A-J) and 34 HBV subgenotypes have been identified so far. HBV genotypes and subgenotypes have distinct geographical distributions, and have been shown to differ with regard to clinical outcome, prognosis, and response to interferon treatment. Infection with subgenotype A2 is frequently associated with high viral load, resulting in acute infection via horizontal transmission. Genotypes A and B are more sensitive to interferon treatment than genotypes D and C, respectively. Genotype B is more frequent in acute hepatitis than genotype C, whereas genotype C (C2) is more frequently associated with an increased risk of hepatocellular carcinoma (HCC), mostly cirrhotic, as compared with genotype B (B2). Genotype mixture is associated with high viral load and worse outcome of HBV infection. HBV mutations in the S genes, especially amino acids substitution at position 145 (G145R), are associated with immune escape, whereas mutations in the PreS or S genes which impair HBsAg secretion could present a risk to blood safety. HBV variants harboring mutations in the viral polymerase gene that confer resistance to nucleoside analogs may be selected during antiviral therapy. Different genotypes have distinct mutation patterns in the PreS and EnhII/BCP/Precore regions. PreS deletions, C1653T, T1753V, and A1762T/G1764A are associated with an increased risk of HCC. HCC-associated HBV mutants may not transmit via mother-to-child transmission, and are likely generated during HBV-induced pathogenesis. Examination of HBV mutations alone or in combination and host genetic susceptibility will be helpful in classifying the HBV-infected subjects who will develop HCC and need active anti-viral treatments.

Clinical relevance and public health significance of hepatitis B virus genomic variations

Ten hepatitis B virus (HBV) genotypes (A-J) and 34 HBV subgenotypes have been identified so far. HBV genotypes and subgenotypes have distinct geographical distributions, and have been shown to differ with regard to clinical outcome, prognosis, and response to interferon treatment. Infection with subgenotype A2 is frequently associated with high viral load, resulting in acute infection via horizontal transmission. Genotypes A and B are more sensitive to interferon treatment than genotypes D and C, respectively. Genotype B is more frequent in acute hepatitis than genotype C, whereas genotype C (C2) is more frequently associated with an increased risk of hepatocellular carcinoma (HCC), mostly cirrhotic, as compared with genotype B (B2). Genotype mixture is associated with high viral load and worse outcome of HBV infection. HBV mutations in the S genes, especially amino acids substitution at position 145 (G145R), are associated with immune escape, whereas mutations in the PreS or S genes which impair HBsAg secretion could present a risk to blood safety. HBV variants harboring mutations in the viral polymerase gene that confer resistance to nucleoside analogs may be selected during antiviral therapy. Different genotypes have distinct mutation patterns in the PreS and EnhII/BCP/Precore regions. PreS deletions, C1653T, T1753V, and A1762T/G1764A are associated with an increased risk of HCC. HCC-associated HBV mutants may not transmit via mother-to-child transmission, and are likely generated during HBV-induced pathogenesis. Examination of HBV mutations alone or in combination and host genetic susceptibility will be helpful in classifying the HBV-infected subjects who will develop HCC and need active anti-viral treatments.

Evidence for association with hepatocellular carcinoma at the PAPSS1 locus on chromosome 4q25 in a family-based study

A region on chromosome 4q25 has recently been highlighted as linked to hepatocellular carcinoma (HCC). In this study, we performed a family-based association analysis with 67 single-nucleotide polymorphisms (SNPs) to map this linkage region in 240 families with HCC, 212 (88.3%) of which were ascertained through hepatitis B virus surface antigen (HBsAg)-positive index cases. Individual SNP analysis with correction for multiple testing identified 10 SNPs in two correlated haplotype blocks, located in or around the 3'-phosphoadenosine 5'-phosphosulfate synthetase-1 (PAPSS1) gene (all P-values: <0.0075). Our linkage data and GIST (Genotype identity-by-descent sharing test) indicate that 6 of these 10 SNPs contributed to the linkage signal. The haplotype block of the strongest association with HCC extended from the intron 5 to the 3'-flanking region of PAPSS1; multiple consecutive three-SNP haplotypes in this region were significant. The most significant haplotype showed odd ratios of 3.41 (95% confidence interval (CI)=1.36-8.53) for homozygous individuals in a case-unaffected sibling analysis. This haplotype also revealed an association with elevated serum alpha-fetoprotein and with poor survival in familial cases and an independent series of HBsAg-positive cases with small tumor present at the time of hospital admission. These results implicate PAPSS1 as a candidate HCC-susceptibility gene in hepatitis B carriers.

Interaction between interleukin-1beta -31T/C gene polymorphism and drinking and smoking habits on the risk of hepatocellular carcinoma among Japanese

The risk of hepatocellular carcinoma (HCC) increases with the severity of hepatic inflammation. Interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha are proinflammatory cytokines with multiple biological effects and may play essential roles in inflammation-linked tumor development. We conducted a case-control study including 209 incident HCC cases and two control groups (275 hospital controls and 381 patients with chronic liver disease [CLD] without HCC) to investigate whether IL-1B and TNF-A gene polymorphisms influence HCC susceptibility with any interaction with alcohol and tobacco. By comparing HCC cases with CLD patients, we found that IL-1B -31T/C polymorphism was associated with HCC risk among never drinkers and current smokers; adjusted odds ratios (and 95% confidence intervals) for C/T and T/T genotypes compared with C/C genotype were 1.70 (0.76-3.77) and 2.46 (1.05-5.76) (P trend=0.03), respectively, among never drinkers, and 1.53 (0.60-3.99) and 2.54 (0.81-7.95) (P trend=0.11), respectively, among current smokers. Similarly, HCC risk associated with heavy alcohol intake and current smoking differed by this polymorphism among CLD patients. IL-1B -31T/C polymorphism may modify HCC risk in relation to alcohol intake or smoking.

DNA repair gene XPD polymorphisms and cancer risk: a meta-analysis based on 56 case-control studies

Genetic variations in the XPD gene may increase cancer susceptibility by affecting the capacity for DNA repair. Several studies have investigated this possibility; however, the conclusions remain controversial. Therefore, we did a systematic review and executed a meta-analysis to explore the association. From 56 studies, a total of 61 comparisons included 25,932 cases and 27,733 controls concerning the Lys 751Gln polymorphism; 35 comparisons included 16,781 cases and 18,879 controls in the case of Asp 312 Asn were reviewed. In this analysis, small associations of the XPD Lys 751 Gln polymorphism with cancer risk for esophageal cancer [for Lys/Gln versus Lys/Lys: odds ratio (OR), 1.34; 95% confidence interval (95% CI), 1.10-1.64; for Gln/Gln versus Lys/Lys: OR, 1.61; 95% CI, 1.16-2.25] and acute lymphoblastic leukemia (for Gln/Gln versus Lys/Lys: OR, 1.83; 95% CI, 1.21-2.75) are revealed. Overall, individuals with the Gln/Gln genotype have a small cancer risk compared with Lys/Lys genotype for the reviewed cancer in total (OR, 1.10; 95% CI, 1.03-1.16). Subtle but significant cancer risk was observed for the XPD Asp 312 Asn polymorphism in bladder cancer (for Asp/Asn versus Asp/Asp: OR, 1.24; 95% CI, 1.06-1.46). No significant associations were found for other cancers separately and all the reviewed cancer in total assessed for the Asp 312 Asn polymorphism. Our study suggests that XPD is a candidate gene for cancer susceptibility regardless of environmental factors.

Glutathione S-transferases pi 1, alpha 1 and M3 genetic polymorphisms and the risk of hepatocellular carcinoma in humans

INTRODUCTION

Glutathione S-transferases pi1, alpha1 and micro3 are members of an enzymatic superfamily involved in the conjugation and detoxification of carcinogens. Polymorphisms affecting the genes encoding these enzymes may modify their ability to neutralize carcinogens. Our aim was to investigate whether these polymorphisms affect the risk of developing hepatocellular carcinoma in humans.

METHODS

A total of 184 white Spanish patients diagnosed with hepatocellular carcinoma and 248 healthy control subjects from the same ethnic origin were included. GSTA1*B promoter allele, GSTM3*B 3-bp-deleted allele and GSTP1 Ile105Val SNP were identified.

RESULTS

No differences were found between the distribution of the studied polymorphisms, or in the allele frequencies for variant alleles in patients and controls: 0.411 and 0.371 for GSTA1, 0.116 and 0.131 for GSTM3, and 0.285 and 0.309 for GSTP1, respectively. Among patients the GSTP1 mutated allele was more frequent in those drinking more than 50 g ethanol/day (odds ratio: 2.00; 95% confidence intervals: 1.06-3.78). Age at diagnosis, gender, tobacco use and hepatitis B and C viral status did not influence these results.

CONCLUSION

We conclude that the studied polymorphisms affecting GSTP1, GSTA1 and GSTM3 genes are probably not related to the risk of developing hepatocellular carcinoma in the studied population.

Tumor necrosis factor-alpha 308.2 polymorphism is associated with advanced hepatic fibrosis and higher risk for hepatocellular carcinoma

BACKGROUND/AIMS

Host genetic factor and hepatic fibrosis may predispose to risk for hepatocellular carcinoma (HCC). This study aimed to assess the association between tumor necrosis factor (TNF) alpha polymorphism and hepatic fibrosis, and risk for HCC.

METHODS

One hundred eight pairs of gender-matched and age-matched patients with HCC and unrelated healthy controls were genotyped for TNF308.2 and TNF238.2 alleles with polymerase chain reaction and direct sequencing.

RESULTS

The frequency of TNF308.1/TNF308.2 genotype in cases was higher than that in controls [odds ratio (OR) = 4.37]. Multivariate analysis indicated that TNF308.2 allele (OR = 3.23), hepatitis B surface antigen (OR = 17.17), and antibodies to hepatitis C virus (OR = 45.52) were independent risk factors for HCC. Surrogate markers for significant fibrosis implied that cases with the TNF308.2 allele have more advanced liver fibrosis. Moreover, multivariate analysis indicated that cirrhosis with Child-Pugh grade C, low serum albumin, and low platelet count were independent risk factors for carrying the TNF308.2 allele.

CONCLUSIONS

TNF308.2 allele carriage and chronic hepatitis B virus/hepatitis C virus infection are independent risk factors for HCC. Carriage of the TNF308.2 allele correlates with disease severity and hepatic fibrosis, which may contribute to a higher risk for HCC.

DNA-repair and carcinogen-metabolising enzymes genetic polymorphisms as an independent risk factor for hepatocellular carcinoma in Caucasian liver-transplanted patients

We studied polymorphisms of three genes, UDP-glucuronosyltransferase1A7 (UGT1A7), Glutathione-S-transferaseM1 (GSTM1) and X-Ray Cross Complementing group 1 (XRCC1), involved in detoxification of xenobiotics or DNA-repair in a population of 133 liver-transplanted patients, including 56 patients with hepatocellular carcinoma (HCC) and 77 without HCC, and in 89 healthy controls originating from the south of France. Multiple logistic regression analysis showed that, among liver-transplanted patients, interactions between XRCC1-G/G or -G/A and GSTM1-nul polymorphisms were independently associated with hepatocellular carcinoma (p interaction=0.027) concurrently with increasing age (p<0.001), male sex (p=0.037) and chronic hepatitis B or C virus infection (p=0.018 and p=0.001 respectively). On the contrary, no relationship was observed between UGT1A7 polymorphisms considered alone or in interaction with GSTM1 or XRCC1 polymorphisms and HCC. This suggests that concomitant impaired metabolism of carcinogenic compounds and impaired DNA-repair function play an important role in liver carcinogenesis in high-risk cirrhotic patients originating from the south of France.

Polymorphisms of interleukin-1beta in Japanese patients with hepatitis B virus infection

BACKGROUND/AIMS

Hepatitis B virus (HBV) induces liver cirrhosis (LC) and hepatocellular carcinoma (HCC) mainly by causing chronic necro-inflammatory hepatic disease. Our aim was to investigate the relationships between the polymorphisms of the interleukin-1B (IL-1B) promoter region and the interleukin-1 receptor antagonist gene (IL-1RN) and disease progression in an HBV-infected Japanese population.

METHODS

Genomic DNA was extracted from the peripheral blood of 237 HBV carriers. Polymorphisms in IL-1B and IL-1RN were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and PCR with confronting two-pair primers (PCR-CTPP) methods. These polymorphic sites include the promoter regions of IL-1B at positions -511 and -31, and IL-1RN variable tandem repeats.

RESULTS

The IL-1B -31 and -511 loci were in complete linkage disequilibrium, and the frequency of the IL-1B -31 T carrier (IL-1B -31 T/T or T/C) was significantly higher in HBV carriers with LC compared to those without LC (LC; 86.1% vs non-LC; 72.1%, P=0.009). There was no difference in the genotype distribution of the IL-1RN polymorphism.

CONCLUSIONS

This is the first report describing the association between IL-1B polymorphism and HBV-related hepatic fibrosis, and our data suggest that IL-1B polymorphisms may be related to disease progression of HBV-related hepatitis in Japan.