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

Association between the risk of hepatitis virus-related hepatocellular carcinoma and EGF polymorphism: A PRISMA-compliant updated meta-analysis

BACKGROUND

The study aims to provide a comprehensive account of the association between the epidermal growth factor (EGF) + 61A/G polymorphism (rs4444903) and susceptibility to virus-related hepatocellular carcinoma (HCC).

METHODS

Electronic searching of the Chinese National Knowledge Infrastructure, Wanfang, Chinese Scientific Journal Database (VIP), PubMed, Web of Science, and Embase was conducted to select eligible studies. Odds ratios (OR) and 95% confidence intervals (95%CI) were calculated to assess the strength of the association.

RESULTS

In this study, a total of 18 articles were included with 2692 cases and 5835 controls for assessing the association between rs4444903 and HCC risk. The pooled results showed that the EGF + 61A/G polymorphism was significantly associated with the risk of virus-related HCC in all genetic models. Stratified analyses were conducted based on ethnicity, study quality, source of controls, type of controls, number of cases and genotyping method. The results showed that EGF + 61A/G polymorphisms significantly affect HCC susceptibility in different stratified populations. High heterogeneity was observed across included studies, and meta-regression analysis demonstrated that race, type of controls, and study quality contribute to the observed heterogeneity.

CONCLUSION

This pooled analysis found that EGF + 61A/G polymorphism was significantly associated with the risk of HCC.

NOTCH3 rs1043996 Polymorphism Is Associated with the Occurrence of Alcoholic Liver Cirrhosis Independently of PNPLA3 and TM6SF2 Polymorphisms

Alcoholic liver cirrhosis (ALC) is the most common indication for liver transplantation (LT) in Croatia and presents a risk factor for the development of hepatocellular carcinoma (HCC). However, genetic susceptibility has not yet been systematically studied. We aimed to investigate the contribution of the risk polymorphisms PNPLA3 rs738409, EGF rs4444903, TM6SF2 rs58542926, MTHFR rs1801133, previously identified in other populations and, additionally, the contribution of Notch-related polymorphisms (NOTCH1 rs3124591, NOTCH3 rs1043996 and rs1044116, NOTCH4 rs422951). The study included 401 patients. The ALC group consisted of 260 LT candidates, 128 of whom had histopathologically confirmed HCC, and 132 of whom were without HCC. The control group included 141 patients without liver disease. Genotyping was performed by PCR using Taqman assays. The patients' susceptibility to ALC was significantly associated with PNPLA3 rs738409, TM6SF2 rs58542926, and NOTCH3 rs1043996 polymorphisms. These polymorphisms remained significantly associated with ALC occurrence in a logistic regression model, even after additional model adjustment for sex and age. Cirrhotic patients with the PNPLA3 GG genotype demonstrated higher activity of ALT aminotransferases than patients with CC or CG genotypes. The susceptibility to the development of HCC in ALC was significantly associated with PNPLA3 rs738409 and EGF rs4444903 polymorphisms, and logistic regression confirmed these polymorphisms as independent predictors.

EGF rs4444903 polymorphism is associated with risk of HCV-related cirrhosis and HBV/HCV-related hepatocellular carcinoma

OBJECTIVE

The epidermal growth factor (EGF) rs4444903 polymorphism is associated with aberrant expression of EGF, which was a characteristic of cirrhotic liver diseases, induces highly malignant hepatocellular carcinoma (HCC). Numerous studies have uncovered the association of this polymorphism with the risk of liver disease, but with inconsistent findings.

MATERIALS AND METHODS

Therefore, this meta-analysis was performed to evaluate whether EGF rs4444903 polymorphism conferred susceptibility to liver disease. Totally 18 eligible articles were identified by searching PubMed, Google, CNKI and EMBASE up to December 1, 2020.

RESULTS

Our results indicated that there was no significant difference in the minor G allele frequency of rs4444903 polymorphism between HBV/HCV carriers and healthy controls. In other words, EGF rs4444903 polymorphism was not associated with the risk of HBV/HCV. Interestingly, this polymorphism increased the risk of liver cirrhosis in the controls with HCV infection. Additionally, EGF rs4444903 polymorphism is associated with the increased risk of HCC under the five models. Subgroup analysis by ethnicity shows that rs4444903 polymorphism intensifies the risk of HCC among Asians and Caucasians. Strong correlation is also reported in controls with cirrhosis or HCV infection and studies using PCR-RFLP genotyping.

CONCLUSIONS

The study supports that EGF rs4444903 polymorphism is a genetic contributor to liver cirrhosis and HCC in the overall population. Nevertheless, this conclusion must be confirmed by larger studies with more diverse ethnic populations.

Alcohol and hepatocarcinogenesis

An excessive alcohol intake may result in fatty liver, acute/chronic hepatitis, cirrhosis, and lead to hepatocellular carcinoma (HCC). The aim of this review is to clarify the present condition and the mechanisms of alcohol-related hepatocarcinogenesis and clinical risk factors for alcohol-related HCC. There are several possible mechanisms through which alcohol may induce hepatocarcinogenesis, including the mutagenic effects of acetaldehyde toxicity through the formation of protein and DNA adducts and the production of reactive oxygen species due to the excessive hepatic deposition of iron, changes to lipid peroxidation and metabolism, inflammation and an impaired immune response and modifications to DNA methylation. Furthermore, it has been reported that alcohol accelerates liver carcinogenesis through several signaling pathways including gut-liver axis. From a clinical perspective, it is well known that alcohol interacts with other factors, such as age, gender, viral hepatitis, obesity, and diabetes leading to an increased risk of HCC.

Genetic Polymorphism of Epidermal Growth Factor Gene as a Predictor of Hepatocellular Carcinoma in Hepatitis C Cirrhotic Patients

Background:

In Egypt, the incidence of hepatocellular carcinoma (HCC) is approximately 4.7% of chronic liver disease patients due to (HCV) infection. Epidermal growth factor (EGF) plays an important role in hepatocyte regeneration. A functional polymorphism in EGF 61A>G was identified; itwas associated with higher risk of HCC.

Objectives:

to investigate the correlation between the epidermal growth factor (EGF) polymorphism and the risk of hepatocellular carcinoma (HCC) in hepatitis C viral (HCV) cirrhotic patients as well as its relation to EGF protein expression in HCC tissue.

Patients and methods:

this casecontrol study was conducted on 75 HCV cirrhotic patients including 50 HCC patients (25 withresectable HCC and 25 with advanced unresectable HCC) and 25 healthy persons were included. EGF genotype was detected by restriction fragment length polymorphism. EGF expression in HCC tissue biopsiesfrom patientswhounderwent surgical resection was done by immunohistochemical examination.

Results:

The GG genotype was associated with significant increased risk of HCC compared to AA genotypes (P=0.031) in cirrhotic group. The G allele had a highly significant risk of HCC compared to allele Ain recessive model GG vs. AG+AA (P=0.036) rather than in the dominant model GG +AG vs. AA (P=0.66). There was significant increased expression of EGF in tumour tissues in patients with GG genotype compared to AG genotype and AA genotype p= 0.019.

Conclusion:

EGF gene polymorphism (GG genotype) had a significant risk of HCC development in cirrhotic patients. This is confirmed by increased EGF expression in liver tumor tissue from HCC patients.

Association between polymorphisms of epidermal growth factor 61 and susceptibility of lung cancer: A meta-analysis

To explore the association between epidermal growth factor (EGF) 61A/G polymorphism and lung cancer.All eligible case-control studies published up to August, 2019 were identified by searching PubMed, The excerpta medica database, China Academic Journals Full-text Database, China Biology Medicine, China National Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang databases. Two researchers independently identified the literature, extracted data, and evaluated quality according to inclusion and exclusion criteria. Meta-analysis was performed by Stata 15.0.A total of 6 studies is included, including 1487 cases and 2044 control subjects. Compared with allele A, allele G was considered to have no association with the risk of lung cancer, odds ratio = 1.07 (95% confidence interval: 0.98-1.15). GG recessive genotype, GG + GA dominant genotype, GG homozygote genotype and GA heterozygote genotype were found out that all of them are not associated with the risk of lung cancer. No association between EGF 61A/G polymorphism and lung cancer was found out by ethnical subgroup analysis. However, in view of the limitations of this study, such as the results of quantitative and sensitivity analysis may be lack of accuracy, so the conclusions of allele model and recessive gene model should be made carefully.It suggested that there was no association between polymorphism of EGF 61A/G and susceptibility of lung cancer.

Single nucleotide polymorphism of rs2596542 and the risk of hepatocellular carcinoma development: A meta-analysis

BACKGROUND

Major histocompatibility complex class I-related chain A (MICA) is considered as a tumor antigen, and its expression is affected by its genetic polymorphisms. However, the relationship between rs2596542 polymorphisms in MICA promoter region and hepatocellular carcinoma (HCC) is not fully elucidated so far. This study aims to explore the relationship between single nucleotide polymorphism of rs2596542 and the risk of HCC development through meta-analysis.

METHODS

MEDLINE, Web of Science, and EMBASE databases were systematically searched to identify relevant studies. A meta-analysis was performed to examine the association between MICA rs2596542 polymorphism and susceptibility to HCC. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

Fourteen case-control studies involving 4,900 HCC cases and 19,519 controls were included. The MICA rs2596542C allele was significantly associated with decreased risk of HCC based on allelic contrast (OR = 0.76, 95% CI = 0.69-0.83, P < .001), homozygote comparison (OR = 0.57, 95% CI = 0.48-0.69, P < .001), and a recessive genetic model (OR = 0.77, 95% CI = 0.65-0.91, P < .001), whereas patients carrying the MICA rs2596542TT genotype had significantly higher risk of HCC than those with the CT or CC genotype (TT vs CT + CC, OR = 1.57, 95% CI = 1.36-1.81, P < .001). Subgroups analyses based on the ethnic or the source of control groups found very similar findings.

CONCLUSION

The C allele in MICA rs2596542 is a protective factor for hepatocarcinogenesis, whereas the T allele is a risk factor. Further large and well-designed studies are needed to confirm this conclusion.

Hepatocellular carcinoma in the setting of alcohol-related liver disease

Alcohol-related liver disease is the most prevalent type of chronic liver disease worldwide, accounting for 30% of hepatocellular carcinoma (HCC) cases and HCC-specific deaths. Alcohol has been associated with an increased risk of several malignancies, this risk starting at doses as low as 10 g/1 unit/day. The carcinogenic process includes direct acetaldehyde toxicity through the formation of protein and DNA adducts, an increased production of reactive oxygen species, changes to lipid peroxidation and metabolism, inflammation and an impaired immune response and modifications to DNA methylation. A high annual incidence of HCC has been observed in large European cohorts of patients with alcoholic cirrhosis, reaching 2.9%, with numerous host factors modulating this risk (age, gender, liver failure, genetic polymorphisms affecting oncogenic pathways). Because of impaired surveillance and poor patient compliance, HCC is often detected late in patients with chronic liver disease of alcoholic aetiology. This delay in detection, which is frequently made in the context of advanced liver cirrhosis rather than in surveillance programmes, results in more advanced HCC that is less amenable to curative treatment. Consequently, patients with alcohol-related HCC generally have a worse prognosis than those with non-alcoholic HCC.

Risk factors and prevention of hepatocellular carcinoma in the era of precision medicine

Patients who develop chronic fibrotic liver disease, caused by viral or metabolic aetiologies, are at a high risk of developing hepatocellular carcinoma (HCC). Even after complete HCC tumour resection or ablation, the carcinogenic tissue microenvironment in the remnant liver can give rise to recurrent de novo HCC tumours, which progress into incurable, advanced-stage disease in most patients. Thus, early detection and prevention of HCC development is, in principle, the most impactful strategy to improve patient prognosis. However, a "one-size-fits-all" approach to HCC screening for early tumour detection, as recommended by clinical practice guidelines, is utilised in less than 20% of the target population, and the performance of screening modalities, including ultrasound and alpha-fetoprotein, is suboptimal. Furthermore, optimal screening strategies for emerging at-risk patient populations, such as those with chronic hepatitis C after viral cure, or those with non-cirrhotic, non-alcoholic fatty liver disease remain controversial. New HCC biomarkers and imaging modalities may improve the sensitivity and specificity of HCC detection. Clinical and molecular HCC risk scores will enable precise HCC risk prediction followed by tailoured HCC screening of individual patients, maximising cost-effectiveness and optimising allocation of limited medical resources. Several aetiology-specific and generic HCC chemoprevention strategies are evolving. Epidemiological and experimental studies have identified candidate chemoprevention targets and therapies, including statins, anti-diabetic drugs, and selective molecular targeted agents, although their clinical testing has been limited by the lengthy process of cancer development that requires long-term, costly studies. Individual HCC risk prediction is expected to overcome the challenge by enabling personalised chemoprevention, targeting high-risk patients for precision HCC prevention and substantially improving the dismal prognosis of HCC.

Constitutional and functional genetics of human alcohol-related hepatocellular carcinoma

Exploration of the constitutional genetics of hepatocellular carcinoma (HCC) has identified numerous variants associated with a higher risk of liver cancer in alcoholic cirrhotic patients. Although Genome-Wide Association studies have not been carried out in the field of alcohol-related HCC, common single nucleotide polymorphisms conferring a small increase in the risk of liver cancer risk have been identified and shown to modulate ethanol metabolism, inflammation, oxidative stress, iron or lipid metabolism. Specific patterns of gene mutations including CTNNB1, TERT, ARID1A and SMARCA2 exist in alcohol-related HCC. Moreover, a specific mutational process observed at the nucleotide level by next generation sequencing has revealed cooperation between alcohol and tobacco in the development of HCC. Combining this genetic information with epidemiological and clinical data that might define specific HCC risk classes and refine surveillance strategies needs to be assessed in large prospective cohorts of patients with alcoholic cirrhosis.

Association of the epidermal growth factor gene +61A>G polymorphism with hepatocellular carcinoma in an Iranian population

AIM

The aim of this study was to address the association of the EGF gene +61A/G polymorphisms and HCC susceptibility in an Iranian population.

BACKGROUND

The association of epidermal growth factor (EGF) gene +61A/G polymorphism (rs4444903) and hepatocellular carcinoma (HCC) has been investigated in several populations. However, the findings are controversial.

METHODS

A total of 40 unrelated HCC patients and 106 healthy individuals were enrolled in this study. Genomic DNA of HCC patients was extracted from formalin-fixed, paraffin-embedded samples using CinnaPure DNA kit according to manufacturer's instructions. Genomic DNA of healthy individuals, also, was extracted from peripheral blood cells using the boiling method. The rs4444903 (A/G) polymorphism was genotyped using the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method.

RESULTS

Significant association was found for the EGF +61A allele and HCC risk [OR = 1.72, 95% CI (1.02 - 2.90), P value = 0.04]. Also, significant association was observed for the EGF +61A/G genotypes and HCC risk under codominant and dominant models by SNPStats software analysis.

CONCLUSION

Our findings suggest that the EGF gene +61A/G polymorphism (rs4444903) might be a risk factor for susceptibility to HCC in Iranian population. However, further studies using more samples are needed.

Meta-analysis of associations of interleukin-28B polymorphisms rs8099917 and rs12979860 with development of hepatitis virus-related hepatocellular carcinoma

Background

This meta-analysis aimed to assess available evidence on possible associations of interleukin-28B polymorphisms rs8099917 and rs12979860 with development of hepatitis virus-related hepatocellular carcinoma (HCC).

Methods

PubMed, EMBASE, Google Scholar, and the Chinese National Knowledge Infrastructure databases were systematically searched to identify relevant studies. Meta-analyses were performed to examine the association of interleukin-28B rs8099917 G/T and rs12979860 T/C polymorphisms with development of hepatitis virus-related HCC. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results

A total of ten studies involving 2,529 cases and 2,412 controls were included. The G-allele and GT genotype of rs8099917 were significantly associated with increased risk of hepatitis B virus (HBV)-related HCC (allelic model, OR 1.49, 95% CI 1.13–1.96, P=0.005; heterozygous model, OR 1.39, 95% CI 1.04–1.88, P=0.03). Conversely, the TT genotype was found to be significantly associated with lower risk of HBV-related HCC (dominant model, OR 0.68, 95% CI 0.51–0.91, P=0.01). Similar results were observed in the subgroup of Chinese patients and controls. In the pooled data set, the T-allele and TT genotype of rs12979860 showed a significant association with increased HCC risk (allelic model, OR 1.36, 95% CI 1.05–1.78, P=0.02; recessive model, OR 1.75, 95% CI 1.28–2.39, P=0.005; homozygous model, OR 1.99, 95% CI 1.41–2.80, P<0.001). Subgroup analysis based on ethnicity and etiology showed rs12979860 polymorphism to be significantly associated with HCC risk in Caucasians, especially hepatitis C virus-related HCC, according to all five genetic models. In contrast, only the TT genotype of rs12979860 was found to be significantly associated with increased risk of HBV-related HCC, especially in Asians.

Conclusion

The G-allele of rs8099917 may confer elevated risk of HBV-related HCC, while the wild-type TT genotype may protect against the disease. The T-allele of rs12979860 may increase the risk of HCC, in Caucasians, especially hepatitis C virus-related HCC. The TT genotype of rs12979860 may confer increased risk of HBV-related HCC, especially in Asians. These conclusions should be verified in large, well-designed studies.

Association of the miR-196a2 C>T and miR-499 A>G polymorphisms with hepatitis B virus-related hepatocellular carcinoma risk: an updated meta-analysis

Background

This study meta-analyzed data on the possible association of the miR-196a2 C>T (rs11614913) and miR-499 A>G (rs3746444) polymorphisms with risk of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC).

Methods

Databases in PubMed, EMBASE, Web of Science, China BioMedicine, and Google Scholar were systematically searched to identify relevant studies. Meta-analyses were performed to examine the association of the miR-196a2 C>T and miR-499 A>G polymorphisms with HBV-related HCC risk. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated.

Results

A total of 13 studies involving 3,964 cases and 5,875 healthy controls were included. Random-effect meta-analysis showed that the T allele and TT genotype of miR-196a2 C>T were associated with significantly lower HBV-related HCC risk (allelic model, OR =0.84, 95% CI =0.71–0.99, P=0.04; homozygous model, OR =0.68, 95% CI =0.47–0.98, P=0.04). In contrast, miR-499 A>G showed no significant association with HBV-related HCC risk in either overall pooled analysis or ethnic subgroup analysis according to any of the four genetic models. Based on analysis of ethnic subgroups, neither miR-196a2 C>T nor miR-499 A>G was significantly associated with risk of HBV-related HCC in Chinese population.

Conclusion

The polymorphism miR-196a2 C>T, but not miR-499 A>G, may be associated with decreased HBV-related HCC risk. These conclusions should be verified in large, well-designed studies.

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.

New advances in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the leading cause of deaths in cirrhotic patients and the third cause of cancer related deaths. Most HCC are associated with well known underlying risk factors, in fact, HCC arise in cirrhotic patients in up to 90% of cases, mainly due to chronic viral hepatitis and alcohol abuse. The worldwide prevention strategies are conducted to avoid the infection of new subjects and to minimize the risk of liver disease progression in infected patients. HCC is a condition which lends itself to surveillance as at-risk individuals can readily be identified. The American and European guidelines recommended implementation of surveillance programs with ultrasound every six months in patient at-risk for developing HCC. The diagnosis of HCC can be based on non-invasive criteria (only in cirrhotic patient) or pathology. Accurately staging patients is essential to oncology practice. The ideal tumour staging system in HCC needs to account for both tumour characteristics and liver function. Treatment allocation is based on several factors: Liver function, size and number of tumours, macrovascular invasion or extrahepatic spread. The recommendations in terms of selection for different treatment strategies must be based on evidence-based data. Resection, liver transplant and interventional radiology treatment are mainstays of HCC therapy and achieve the best outcomes in well-selected candidates. Chemoembolization is the most widely used treatment for unresectable HCC or progression after curative treatment. Finally, in patients with advanced HCC with preserved liver function, sorafenib is the only approved systemic drug that has demonstrated a survival benefit and is the standard of care in this group of patients.

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.

Association between the epidermal growth factor 61*A/G polymorphism and hepatocellular carcinoma risk: a meta-analysis

The epidermal growth factor (EGF) may play a pathological role in hepatocellular carcinoma (HCC). However, the conclusions of published reports on the relationship between the EGF 61*A/G polymorphism and HCC risk remain controversial. To derive a more precise estimation we performed a meta-analysis based on 14 studies that together included 2,506 cases and 4,386 controls. PubMed, EMBASE, Web of Knowledge and the Chinese National Knowledge Infrastructure (CNKI) databases were used to retrieve articles up to August 1, 2014. The crude odds ratios (ORs) with 95% confidence intervals (95%CIs) were calculated to evaluate the association. Meta-analysis results showed a significant association between the EGF 61*A/G polymorphism and HCC risk in all four genetic models (allele model: OR=1.25, 95%CI=1.12-1.40; dominant model: OR=1.32, 95%CI=1.14-1.54; recessive model: OR=1.33, 95%CI=1.12-1.58; homozygous model: OR=1.59, 95%CI=1.33- 1.90). Moreover, significant associations were observed when stratified by ethnicity, source of controls, etiology and genotype methods. Thus, this meta-analysis suggests that the G-allele of the EGF 61*A/G polymorphism is associated with an increased risk of HCC, especially in Asians and Caucasians, without influence from the source of controls or etiological diversity. Further studies with larger population sizes are needed to confirm these results.

Association between COX-2 gene polymorphisms and risk of hepatocellular carcinoma development: a meta-analysis

OBJECTIVE

To investigate the association between cyclo-oxygenase-2 (COX-2) polymorphism and the risk of hepatocellular carcinoma (HCC) development.

DESIGN

Systematic review and meta-analysis of COX-2 polymorphism and risk of HCC development among people with or without HCC.

DATA SOURCES

EMBASE, PubMed, Public Library of Science, SCOPUS, Web of Knowledge and Chinese National Knowledge Infrastructure were searched for all clinical and experimental case-control studies of COX-2 polymorphism and HCC risk. Studies published up to March 2015 were included.

REVIEW METHOD

Ten studies were included for data extraction, which were mainly from Asian countries.

RESULTS

2538 people with HCC and 3714 without HCC were found to satisfy the inclusion criteria and included in the review. The associations of specific genotypes in the eight polymorphic variants of COX-2 and the risk of HCC development were analysed. GG genotype at the A-1195G polymorphism may be associated with a reduced risk of HCC development: the OR across all studies was 0.87 (95% CI 0.75 to 1.02) for the G allele versus the A allele, 0.72 (0.53 to 0.97) for GG versus AA, 0.72 (0.57 to 0.92) for GG versus GA+AA and 1.05 (0.77 to 1.44) for AA versus GA+GG. Similar results were found when the meta-analysis was repeated separately for the Chinese subgroup. However, more reliable data are needed to demonstrate associations between variants in G-765C, T+8473C, A-1290G, G-899C and introns 1, 5 and 6 polymorphisms and the risk of HCC development.

CONCLUSIONS

Only the COX-2 A-1195G gene polymorphism may be associated with a decreased risk of HCC development. These conclusions should be verified in further studies.

Molecular prognostic prediction in liver cirrhosis

The natural history of cirrhosis varies and therefore prognostic prediction is critical given the sizable patient population. A variety of clinical prognostic indicators have been developed and enable patient risk stratification although their performance is somewhat limited especially within relatively earlier stage of disease. Molecular prognostic indicators are expected to refine the prediction, and potentially link a subset of patients with molecular targeted interventions that counteract poor prognosis. Here we overview clinical and molecular prognostic indicators in the literature, and discuss critical issues to successfully define, evaluate, and deploy prognostic indicators as clinical scores or tests. The use of liver biopsy has been diminishing due to sampling variability on fibrosis assessment and emergence of imaging- or lab test-based fibrosis assessment methods. However, recent rapid developments of genomics technologies and selective molecular targeted agents has highlighted the need for biopsy tissue specimen to explore and establish molecular information-guided personalized/stratified clinical care, and eventually achieve “precision medicine”.

Quantitative assessment of the effect of epidermal growth factor 61A/G polymorphism on the risk of hepatocellular carcinoma

The association between hepatocellular carcinoma (HCC) and the epidermal growth factor (EGF) 61A/G polymorphism has been analyzed in several studies, but results remain inconsistent. Therefore, the aim of the present study was to quantitatively summarize the association between the EGF 61A/G polymorphism and the risk of HCC. The PubMed and EMBASE databases were searched for studies published prior to May 1, 2014. The overall, subgroup and sensitivity analyses were conducted using Comprehensive Meta-Analysis software, version 2.2. In total, 12 published case-control studies, consisting of 2,095 patients with HCC and 3,766 control individuals, were included in the present study. Meta-analysis of the included studies revealed that EGF 61A/G polymorphism contributed to the risk of HCC under all four genetic models, consisting of the G vs. A (OR, 1.25; 95% CI, 1.11-1.40), GG vs. AA (OR, 1.53; 95% CI, 1.26-1.85), GG vs. AG + AA (OR, 1.34; 95% CI, 1.13-1.58) and GG + AG vs. AA (OR, 1.27; 95% CI, 1.08-1.49) comparisons. Subgroup analysis further suggested that EGF 61A/G polymorphism was associated with the risk of HCC in patients and control individuals with liver disease, based on ethnicity and source of control, respectively. No other significance in residual subgroup analysis was observed. The present meta-analysis suggests that the EGF 61A/G polymorphism is associated with an increased risk of HCC and may be a potential marker for liver disease, such as hepatitis B virus infection, hepatitis C virus infection and liver cirrhosis.

Polymorphism in epidermal growth factor is related to clinical outcomes of metastatic colorectal cancer patients treated with cetuximab: a systematic review and meta-analysis

Numerous studies focusing on genetic variants in order to find cetuximab subpopulation biomarkers have emerged, yet the significance of each biomarker is diverse. Based on these results, we carried out a meta-analysis to assess the correlation between epidermal growth factor (EGF) A61G polymorphism and clinical outcomes of metastatic colorectal cancer (mCRC) patients treated with cetuximab. We aim to prove that EGF polymorphisms may be potential biomarkers for cetuximab therapeutic strategies. We identified 6 previously published studies including 569 patients treated with cetuximab-based regimens. Outcomes included clinical response, progression-free survival (PFS), and overall survival (OS). GG homozygote showed association with better response rates (GG vs. AA+AG, OR = 2.82; 95% CI = 1.58-5.04) and than AA+AG genotypes. This meta-analysis showed that mCRC patients harboring GG genotype of EGF A61G polymorphism inclined to have a better response rate with cetuximab treatment.

β-PDGF receptor expressed by hepatic stellate cells regulates fibrosis in murine liver injury, but not carcinogenesis

BACKGROUND & AIMS

Rapid induction of β-PDGF receptor (β-PDGFR) is a core feature of hepatic stellate cell activation, but its cellular impact in vivo is not well characterized. We explored the contribution of β-PDGFR-mediated pathway activation to hepatic stellate cell responses in liver injury, fibrogenesis, and carcinogenesis in vivo using genetic models with divergent β-PDGFR activity, and assessed its prognostic implications in human cirrhosis.

METHODS

The impact of either loss or constitutive activation of β-PDGFR in stellate cells on fibrosis was assessed following carbon tetrachloride (CCl4) or bile duct ligation. Hepatocarcinogenesis in fibrotic liver was tracked after a single dose of diethylnitrosamine (DEN) followed by repeated injections of CCl4. Genome-wide expression profiling was performed from isolated stellate cells that expressed or lacked β-PDGFR to determine deregulated pathways and evaluate their association with prognostic gene signatures in human cirrhosis.

RESULTS

Depletion of β-PDGFR in hepatic stellate cells decreased injury and fibrosis in vivo, while its auto-activation accelerated fibrosis. However, there was no difference in development of DEN-induced pre-neoplastic foci. Genomic profiling revealed ERK, AKT, and NF-κB pathways and a subset of a previously identified 186-gene prognostic signature in hepatitis C virus (HCV)-related cirrhosis as downstream of β-PDGFR in stellate cells. In the human cohort, the β-PDGFR signature was not associated with HCC development, but was significantly associated with a poorer outcome in HCV cirrhosis.

CONCLUSIONS

β-PDGFR is a key mediator of hepatic injury and fibrogenesis in vivo and contributes to the poor prognosis of human cirrhosis, but not by increasing HCC development.

Association between epidermal growth factor gene +61A/G polymorphism and the risk of hepatocellular carcinoma: a meta-analysis based on 16 studies

Background

The association between epidermal growth factor (EGF) gene +61A/G polymorphism (rs4444903) and hepatocellular carcinoma (HCC) susceptibility has been widely reported, but the results were inconsistent. To clarify the effect of this polymorphism on HCC risk, a meta-analysis was performed.

Methods

The PubMed, Embase, Cochrane Library, Web of Science, Chinese BioMedical Literature (CBM), Wanfang and Chinese National Knowledge Infrastructure (CNKI) databases were systematically searched to identify relevant studies published up to December 2013. Data were extracted independently by two authors. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated to assess the strength of association.

Results

A total of 16 studies including 2475 HCC cases and 5381 controls were included in this meta-analysis. Overall, a significantly increased HCC risk was observed under all genetic models (G vs. A: OR = 1.383, P < 0.001, 95% CI: 1.174-1.629; GG vs. GA + AA: OR = 1.484, P < 0.001, 95% CI: 1.198-1.838; GG + GA vs. AA: OR = 1.530, P < 0.001, 95% CI: 1.217-1.924; GG vs. AA: OR = 1.958, P < 0.001, 95% CI: 1.433-2.675; GA vs. AA: OR = 1.215, P = 0.013, 95% CI: 1.041-1.418). In the subgroup analyses by ethnicity, a significant association with HCC risk was found in Asian populations (G vs. A: OR = 1.151, P = 0.001, 95% CI: 1.056-1.255), European populations (G vs. A: OR = 1.594, P = 0.027, 95% CI: 1.053-2.413, and African populations (G vs. A: OR = 3.599, P < 0.001, 95% CI: 2.550-5.080), respectively.

Conclusions

Our study shows that EGF +61A/G polymorphism is significantly associated with the increased HCC risk, especially in Asian populations. Further large-scale and well-designed studies are required to confirm this conclusion.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1318-6) contains supplementary material, which is available to authorized users.

Aberrant Cosmc genes result in Tn antigen expression in human colorectal carcinoma cell line HT-29

The Tn antigen, which arises from mutation in the Cosmc gene is one of the most common tumor associated carbohydrate antigens. Cosmc resides in X24 encoded by a single gene and functions as a specific molecular chaperone for T-synthase. While the Tn antigen cannot be detected in normal cells, Cosmc mutations inactivate T-synthase and consequently result in Tn antigen expression within certain cancers. In addition to this Cosmc mutation-induced expression, the Tn antigen is also expressed in such cell lines as Jurkat T, LSC and LS174T. Whether the Cosmc mutation is present in the colon cancer cell line HT-29 is still unclear. Here, we isolate HT-29-Tn+ cells from HT-29 cells derived from a female colon cancer patient. These HT-29-Tn+ cells show a loss of the Cosmc gene coding sequence (CDS) leading to an absence of T-synthase activity and Tn antigen expression. Additionally, almost no methylation of Cosmc CpG islands was detected in HT-29-Tn+ as well as in HT-29-Tn- and Tn- tumor cells from male patients. In contrast, the methylation frequency of CpG island of Cosmc in normal female cells was ~50%. Only one active allele of Cosmc existed in HT-29-Tn+ and HT-29-Tn- cells as based upon detection of SNP sites. These results indicate that Tn antigens expression and T-synthase inactivity in HT-29-Tn+ cells can be related to the absence of CDS in Cosmc active alleles, while an inactive allele deletion of Cosmc in HT-29 cells has no influence on Cosmc function.

Genetic risk markers for hepatocellular carcinoma in patients with alcoholic liver disease

Various single nucleotide polymorphisms have been reported to be associated with a higher risk of hepatocellular carcinoma in alcoholic cirrhotic patients. Until now, only common variants conferring a small increase in liver cancer risk have been identified. These inherited factors are able to modulate several biological pathways involved in alcohol-induced hepatocarcinogenesis, such as ethanol metabolism, inflammation, oxidative stress, or iron and lipid homeostasis. How the combination of these variants might collectively define an individual genomic risk prediction is currently being investigated. The other challenge in clinical practice lies in defining how to integrate this genetic information with other clinical parameters so as to refine selection of alcoholic cirrhotic patients according to various classes of hepatocellular carcinoma risk.

Epidermal growth factor receptor pathway polymorphisms and the prognosis of hepatocellular carcinoma

The EGFR signaling pathway is important in the control of vital processes in the carcinogenesis of hepatocellular carcinoma (HCC), including cell survival, cell cycle progression, tumor invasion and angiogenesis. In the current study, we aim to assess if genetic variants in the genes of the EGFR signaling pathway are associated with the prognosis of HCC. We genotyped 36 single nucleotide polymorphisms (SNP) in four core genes (EGF, EGFR, VEGF, and VEGFR2) by using DNA from blood samples of 363 HCC patients with surgical resection. The associations between genotypes and overall survival (OS) and disease-free survival (DFS) were estimated using the Kaplan-Meier method. Hazard ratios (HRs) and 95% confident intervals (CIs) were estimated for the multivariate survival analyses by Cox proportional hazards regression models, adjusting for age, gender, family history, HBsAg and AFP. We found that five SNPs in the VEGFR2 gene were significantly associated with clinical outcomes of HCC patients. Among them, four SNPs (rs7692791, rs2305948, rs13109660, rs6838752) were associated with OS (p=0.035, 0.038, 0.029 and 0.028, respectively), and two SNPs (rs7692791 and rs2034965) were associated with DFS (p=0.039 and 0.017, respectively). Particularly, rs7692791 TT genotype was associated with both reduced OS (p=0.037) and DFS (p=0.043). However, only one SNP rs2034965 with the AA genotype was shown to be an independent effect on DFS (p=0.009) in the multivariate analysis. None of the other 31 polymorphisms or 9 haplotypes attained from the four genes was significantly associated with OS or DFS. Our results illustrated the potential use of VEGFR2 polymorphisms as prognostic markers for HCC patients.

Host genetics predict clinical deterioration in HCV-related cirrhosis

Single nucleotide polymorphisms (SNPs) in the epidermal growth factor (EGF, rs4444903), patatin-like phospholipase domain-containing protein 3 (PNPLA3, rs738409) genes, and near the interleukin-28B (IL28B, rs12979860) gene are linked to treatment response, fibrosis, and hepatocellular carcinoma (HCC) in chronic hepatitis C. Whether these SNPs independently or in combination predict clinical deterioration in hepatitis C virus (HCV)-related cirrhosis is unknown. We genotyped SNPs in EGF, PNPLA3, and IL28B from liver tissue from 169 patients with biopsy-proven HCV cirrhosis. We estimated risk of clinical deterioration, defined as development of ascites, encephalopathy, variceal hemorrhage, HCC, or liver-related death using Cox proportional hazards modeling. During a median follow-up of 6.6 years, 66 of 169 patients experienced clinical deterioration. EGF non-AA, PNPLA3 non-CC, and IL28B non-CC genotypes were each associated with increased risk of clinical deterioration in age, sex, and race-adjusted analysis. Only EGF non-AA genotype was independently associated with increased risk of clinical deterioration (hazard ratio [HR] 2.87; 95% confidence interval [CI] 1.31-6.25) after additionally adjusting for bilirubin, albumin, and platelets. Compared to subjects who had 0-1 unfavorable genotypes, the HR for clinical deterioration was 1.79 (95%CI 0.96-3.35) for 2 unfavorable genotypes and 4.03 (95%CI 2.13-7.62) for unfavorable genotypes for all three loci (Ptrend<0.0001). In conclusion, among HCV cirrhotics, EGF non-AA genotype is independently associated with increased risk for clinical deterioration. Specific PNPLA3 and IL28B genotypes also appear to be associated with clinical deterioration. These SNPs have potential to identify patients with HCV-related cirrhosis who require more intensive monitoring for decompensation or future therapies preventing disease progression.

Hepatitis C virus-associated cancer

Hepatitis C virus (HCV) is one of the major etiologic agents of liver cancer. HCV is an RNA virus that, unlike hepatitis B virus, is unable to integrate into the host genome. Through complex interactions between viral and host proteins that induce host responses and promote inflammation, fibrosis, and ultimately cirrhosis, HCV infection can result in the development of hepatocellular carcinoma (HCC). The HCV oncogenic process involves genetic and epigenetic alterations and oncogenic effects mediated by viral proteins in the activation of cellular oncogenes, inactivation of tumor-suppressor genes, and dysregulation of multiple signal-transduction pathways. Advances in genetics and gene expression profiling have enhanced our current understanding of the pathways involved in HCV-associated liver cancer development. In this review, we summarize the current understanding of mechanisms of hepatocarcinogenesis induced by HCV infection.

Pathogenesis and prevention of hepatitis C virus-induced hepatocellular carcinoma

Hepatitis C virus (HCV) is one of the major aetiologic agents that causes hepatocellular carcinoma (HCC) by generating an inflammatory, fibrogenic, and carcinogenic tissue microenvironment in the liver. HCV-induced HCC is a rational target for cancer preventive intervention because of the clear-cut high-risk condition, cirrhosis, associated with high cancer incidence (1% to 7% per year). Studies have elucidated direct and indirect carcinogenic effects of HCV, which have in turn led to the identification of candidate HCC chemoprevention targets. Selective molecular targeted agents may enable personalized strategies for HCC chemoprevention. In addition, multiple experimental and epidemiological studies suggest the potential value of generic drugs or dietary supplements targeting inflammation, oxidant stress, or metabolic derangements as possible HCC chemopreventive agents. While the successful use of highly effective direct-acting antiviral agents will make important inroads into reducing long-term HCC risk, there will remain an important role for HCC chemoprevention even after viral cure, given the persistence of HCC risk in persons with advanced HCV fibrosis, as shown in recent studies. The successful development of cancer preventive therapies will be more challenging compared to cancer therapeutics because of the requirement for larger and longer clinical trials and the need for a safer toxicity profile given its use as a preventive agent. Molecular biomarkers to selectively identify high-risk population could help mitigate these challenges. Genome-wide, unbiased molecular characterization, high-throughput drug/gene screening, experimental model-based functional analysis, and systems-level in silico modelling are expected to complement each other to facilitate discovery of new HCC chemoprevention targets and therapies.

Postoperative therapy options for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is associated with poor prognosis and often recurs even after curative hepatic resection (HR) or radiofrequency ablation (RFA). In fact, recurrence is the most frequent cause of postoperative death in patients with HCC; it can arise through intrahepatic metastasis by the primary tumor or through the emergence of de novo tumors. Even though studies have examined numerous adjuvant therapies and chemotherapies for their ability to prevent recurrence, no consensus recommendations exist about their clinical application. To gain a comprehensive picture of clinical options, we identified 39 randomized controlled trials, involving 4113 participants, which explore the efficacy of adjuvant or chemotherapies to prevent HCC recurrence after potentially curative HR or RFA. The available evidence suggests a significant improvement in recurrence-free survival and overall survival when transarterial chemoembolization is used for patients who are at high risk for recurrence, lamivudine for patients with hepatitis B virus (HBV)-related HCC (>500 copies of HBV DNA/ml), and interferon-α for patients with hepatitis C virus (HCV)-infected HCC. In contrast, available evidence does not definitively establish clinical benefits of interferon-β for patients with HCV-related HCC, interferon-α for patients with HBV-related HCC, or any of the following therapies for patients with HCC: iodine-125 brachytherapy, autologous tumor vaccination, adoptive immunotherapy, or therapy involving acyclic retinoid, vitamin K2 analog, iodine-131-labeled lipiodol, sorafenib, heparanase inhibitor PI-88, or capecitabine. Though the findings of our review should be interpreted with caution because of clinical heterogeneity and small sample size in the included trials, they highlight gaps in the evidence base, and therefore, may guide future research.

Impact of epidermal growth factor single-nucleotide polymorphism on recurrence of hepatocellular carcinoma after hepatectomy in patients with chronic hepatitis C virus infection

Epidermal growth factor (EGF) gene single-nucleotide polymorphism (SNP) is associated with an increased risk of hepatic tumors. The study aimed to elucidate the impact of EGF SNP and EGF receptor (EGFR) expression on the recurrence of hepatocellular carcinoma (HCC) after hepatectomy. To examine the impact of EGF SNP and EGFR on recurrent HCC, we retrospectively analyzed 141 HCC patients with chronic hepatitis C virus infection who underwent curative hepatectomy. The EGF *61 GG allele was present in 69 patients (48.9%), AG in 56 (39.7%) and AA in 16 (11.4%). The AA group had a significantly lower rate of intrahepatic metastasis (0% vs 16.5%, P = 0.02), lower serum EGF concentration (26.3 ± 15.9 pg/mL vs 43.4 ± 30.5 pg/mL, P = 0.02) and lower proportion of early recurrence (≤2 years; 28.6% vs 71.2%, P = 0.03) than the AG/GG group. The AA group had significantly higher recurrence-free survival than the AG/GG group (P = 0.04), but there was no significant difference in overall survival between these two groups (P = 0.97). High versus low EGFR expression analyzed by immunohistochemical staining in cancer cells was not significantly associated with overall survival (P = 0.37) or recurrence-free survival (P = 0.39). Therefore, EGF *61 AA was associated with a lower risk of recurrence after curative hepatectomy for HCC in patients with hepatitis C virus infection than other genotypes, but EGFR expression in cancer cells was not significantly associated with prognosis.

The interferon-gamma (IFN-γ) +874T allele reduces the risk of hepatitis B infection in an Asian population

Increasing evidence suggests that polymorphism of the interferon-gamma (IFN-γ) gene in the first intron at position +874 may be associated with chronic hepatitis B virus (HBV) infection and/or HBV clearance. However, the results of relevant studies have been inconsistent. To derive a more precise estimation of the association, we performed a meta-analysis. In total, 10 independent studies including 1661 chronic HBV-infected patients and 1142 controls were included in this meta-analysis. In studies following Hardy-Weinberg equilibrium (HWE), a significantly decreased risk of chronic HBV infection was associated with the IFN-γ + 874TT genotype in the overall population (TT vs AA: odds ratio (OR) = 0.714, 95% confidence interval (CI) = 0.526-0.969, P = 0.031) when compared with a spontaneously recovered population. Subgroup analysis by ethnicity revealed a similar association in Asian individuals (TT vs AA: OR = 0.706, 95% CI = 0.518-0.962, P = 0.028). Moreover, when compared with a healthy control group, the 874T allele was associated with a significant lower risk of chronic HBV infection in the overall populations (TA vs AA: OR = 0.439, 95% CI = 0.193-0.997, P = 0.049; TT + TA vs AA: OR = 0.475, 95% CI = 0.271-0.832, P = 0.009) and in Asian individuals (TA vs AA: OR = 0.862, 95% CI = 0.744-0.999, P = 0.048). In conclusion, the IFN-γ + 874TT genotype and 874T allele reduce the risk of chronic HBV infection in Asian individuals.

Virus associated malignancies: the role of viral hepatitis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the third leading fatal cancer worldwide and its incidence continues to increase. Chronic viral hepatitis involving either hepatitis B virus (HBV) or hepatitis C virus (HCV) infection is the leading etiology for HCC, making HCC prevention a major goal of antiviral therapy. While recent clinical observations and translational research have enhanced our understanding of the molecular mechanisms driving the initiation and progression of HCC, much remains unknown. Current data indicates that HCC tumors are highly complex and heterogeneous resulting from the aberrant function of multiple molecular pathways. This complex biology is responsible, at least in part, for the absence of highly efficient target-directed therapies for this deadly cancer. Additionally, the direct or indirect effect of HBV and HCV infection on the development of HCC is still a contentious issue. Thus, the question remains whether viral hepatitis-associated HCC stems from virus-specific factors, and/or from a general mechanism involving inflammation and tissue regeneration. In this review we summarize general mechanisms implicated in HCC, emphasizing data generated by new technologies available today. We also highlight specific pathways by which HBV and HCV could be involved in HCC pathogenesis. However, improvements to current in vitro and in vivo systems for both viruses will be needed to rigorously define the temporal sequence and specific pathway dysregulations that drive the strong clinical link between chronic hepatitis virus infection and HCC.

A functional polymorphism in the epidermal growth factor gene predicts hepatocellular carcinoma risk in Japanese hepatitis C patients

BACKGROUND

A single nucleotide polymorphism (SNP) in the epidermal growth factor (EGF) gene (rs4444903) has been associated with increased risk of cancer, including hepatocellular carcinoma (HCC). The aim of this study was to examine the relationship between the EGF SNP genotype and the development and prognosis of HCC, in a Japanese population.

METHODS

Restriction fragment-length polymorphism was used to determine the presence of the EGF SNP genotype in 498 patients, including 208 patients with HCC. The level of EGF messenger ribonucleic acid (mRNA) expression in cancerous tissues was measured by quantitative reverse transcription polymerase chain reaction. The correlation between the EGF SNP genotype and prognosis was statistically analyzed in the patients with HCC.

RESULTS

The proportion of the A/A, A/G, and G/G genotypes were 5.3%, 42.8%, and 51.9%, respectively, in the patients with HCC, whereas in those without HCC, they were 8.6%, 35.9%, and 55.5%, respectively, revealing that the odds ratio (OR) of developing HCC was higher in patients with a G allele (OR =1.94, P=0.080 for A/G patients and OR =1.52, P=0.261 for G/G patients, as compared with A/A patients). In particular, when the analysis was limited to the 363 patients with hepatitis C, the OR for developing HCC was 3.54 (P=0.014) for A/G patients and was 2.85 (P=0.042) for G/G patients, as compared with A/A patients. Tumoral EGF mRNA expression in G/G patients was significantly higher than that in A/A patients (P=0.033). No statistically significant differences were observed between the EGF SNP genotype and diseasefree or overall survival.

CONCLUSION

The EGF SNP genotype might be associated with a risk for the development of HCC in Japanese patients but not with prognosis. Of note, the association is significantly stronger in patients with hepatitis C, which is the main risk factor for HCC in Japan.

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.

Association of epidermal growth factor and epidermal growth factor receptor polymorphisms with the risk of hepatitis B virus-related hepatocellular carcinoma in the population of North China

BACKGROUND

Hepatocellular carcinoma (HCC) is a common solid malignant tumor occurring worldwide that leads to the third largest cause of death compared to other cancers. Genetic and environmental factors are involved in the pathogenesis of HCC. Epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR) can stimulate the proliferation of epidermal and epithelial cells. The EGF signal pathway has a relationship with the growth of the embryo, tissue repairing, and tumorigenesis.

METHODS

In this study, 416 patients with hepatitis B virus infection (HBV)-related HCC and 645 individuals who had never been infected with HBV of the Chinese Han population were enrolled. Eight single-nucleotide polymorphisms (SNPs), whose minor allele frequency >20% in the EGF and EGFR genes, were genotyped to examine their associations with hepatocarcinogenesis. Genotyping experiments were carried out using TaqMan.

RESULTS

There were significant differences in genotype distributions (p=0.005) and allele frequencies (p=0.001, odds ratio [OR]=1.43, 95% confidence interval [CI]=1.15-1.79) of rs11569017 in the EGF gene between the HCC and control groups. After binary logistic regression to determine independent factors for susceptibility to HCC under an additive model, rs11569017 was still independently associated with the susceptibility to HCC (p=0.021, OR=1.48, 95% CI=1.06-2.07), but no significant differences in other SNPs were found. Additionally, the haplotype T-G constructed by rs11569017 and rs4444903 of the EGF gene might increase the risk of HBV-related HCC (p=0.002, OR=1.44, 95% CI=1.15-1.82).

CONCLUSION

The rs11569017 T allele was associated with susceptibility to HBV-related HCC.

Association between epidermal growth factor gene rs4444903 polymorphism and risk of glioma

The development of glioma is a complex process which may be influenced by many factors including the epidermal growth factor (EGF) gene polymorphism. Previous studies showed that EGF rs4444903 polymorphism could result in increased risk of tumorigenesis in multiple human cancers, but published data regarding the association between EGF rs4444903 polymorphism and glioma risk were inconsistent. To derive a more precise estimation of the association between EGF rs4444903 polymorphism and glioma risk, we performed a systematic review and meta-analysis of previous published studies. PubMed, Embase, and the Wanfang databases were systematically searched to identify relevant studies. Odds ratios (ORs) and 95 % confidence intervals (95 % CIs) were calculated to assess the strength of the association. Ten published studies with 1,891 glioma cases and 2,836 controls were finally included into the study. Overall, there was a significant association between EGF rs4444903 polymorphism and glioma risk in all four genetic models (the allele model: OR=1.25, 95 % CI 1.15-1.37, P<0.001; the codominant model: OR=1.65, 95 % CI 1.36-1.99, P<0.001; the dominant model: OR=1.27, 95 % CI 1.12-1.44, P<0.001; the recessive model: OR=1.48, 95 % CI 1.25-1.75, P<0.001). Subgroup analyses by ethnicity showed that EGF rs4444903 polymorphism resulted in a higher risk of glioma among both Asians and Caucasians. In conclusion, the results suggest that there is a significant association between EGF rs4444903 polymorphism and glioma risk, and genotypes of EGF rs4444903 mutation contribute to increased host susceptibility to glioma.

MTHFR C677T and A1298C polymorphisms were associated with bladder cancer risk and disease progression: a meta-analysis

Epidemiological studies have investigated that functional polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene may play an essential role in bladder carcinogenesis, but the association between these single-nucleotide polymorphisms in the MTHFR gene and the susceptibility of bladder cancer (BC) was inconsistent in previous studies. The objective of this current study was to conduct an update analysis investigating the association between three polymorphisms in the MTHFR gene and the risk of BC. We performed a meta-analysis of 13 publications involving an association between BC and MTHFR gene three polymorphisms (C677T, A1298C, and G1793A). We assessed the strength of the association, using odds ratios (ORs) with 95% confidence intervals (CIs). On one hand, we found that the C677T polymorphism was associated with increased BC risk among Asians, however, with decreased BC risk among a mixed population. Interestingly, BC patients who carried the T-allele (TT+TC) had a higher percentage than the individuals who carried the CC genotype (OR=1.38, 95% CI=1.13-1.69, p=0.002). On the other hand, the A1298C polymorphism may increase BC risk among Asians and Africans, but played a decreased association among Europeans. Results from the current update analysis suggested that the C677T and A1298C polymorphisms in the MTHFR gene were associated with BC risk and disease progression.

Meta-analysis of microsomal epoxide hydrolase gene polymorphism and risk of hepatocellular carcinoma

Background

Hepatocarcinogenesis is a complex process that may be influenced by many factors, including polymorphism in microsomal epoxide hydrolase (mEH). Previous work suggests an association between the Tyr113His and His139Arg mEH polymorphisms and susceptibility to hepatocellular carcinoma (HCC), but the results have been inconsistent.

Methods

PubMed, EMBASE, Google Scholar and the Chinese National Knowledge Infrastructure databases were systematically searched to identify relevant studies. A meta-analysis was performed to examine the association between Tyr113His and His139Arg mEH polymorphism and susceptibility to HCC. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated.

Results

Eleven studies were included in the meta-analysis, involving 1,696 HCC cases and 3,600 controls. The 113His- mEH allele was significantly associated with increased risk of HCC based on allelic contrast (OR = 1.35, 95% CI = 1.04–1.75, p = 0.02), homozygote comparison (OR = 1.65, 95% CI = 1.07–2.54, p = 0.02) and a recessive genetic model (OR = 1.54, 95% CI = 1.21–1.96, p<0.001), while individuals carrying the Arg139Arg mEH genotype had no association with increased or decreased risk of HCC.

Conclusion

The 113His- allele polymorphism in mEH may be a risk factor for hepatocarcinogenesis, while the mEH 139Arg- allele may not be a risk or protective factor. There is substantial evidence that mEH polymorphisms interact synergistically with other genes and the environment to modulate risk of HCC. Further large and well-designed studies are needed to confirm these conclusions.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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