Risk factors for hepatocellular carcinoma: synergism of alcohol with viral hepatitis and diabetes mellitus

Toll-like receptors in the pathogenesis of alcoholic liver disease

In the multifactorial pathophysiology of alcoholic liver disease (ALD), inflammatory cascade activation plays a central role. Recent studies demonstrated that Toll-like Receptors, the sensors of microbial and endogenous danger signals, are expressed and activated in innate immune cells as well as in parenchymal cells in the liver and thereby contribute to ALD. In this paper, we discuss the importance of gut-derived endotoxin and its recognition by TLR4. The significance of TLR-induced intracellular signaling pathways and cytokine production as well as the contribution of reactive oxygen radicals is evaluated. The contribution of TLR signaling to induction of liver fibrosis and hepatocellular cancer is reviewed in the context of alcohol-induced liver disease.

Alcohol and gastrointestinal oncology

Results from several large epidemiological studies have firmly established that alcohol is associated with elevated cancer incidence and mortality. Recently the International Agency for Cancer Research stated that acetaldehyde associated with alcoholic beverages is carcinogenic to humans and confirmed the Group 1 classification of alcohol consumption and of ethanol in alcoholic beverages. Alcohol consumption causes cancers of the oral cavity, pharynx, larynx, oesophagus, colorectum, liver, pancreas and female breast. The frequency of most alcohol-induced diseases increases in a linear fashion as intake increases: oral, oesophagus and colon cancer fall into this pattern. Very little is known about safe margins of alcohol consumption. US Department of Health and Human Services suggest a maximum of 28 g of alcohol a day in man and half of this in women.

Hepatocellular carcinoma: A global view

Hepatocellular carcinoma (HCC) is a global health problem, although developing countries are disproportionally affected: over 80% of HCCs occur in such regions. About three-quarters of HCCs are attributed to chronic HBV and HCV infections. In areas endemic for HCV and HBV, viral transmission occurs at an early age, and infected individuals develop HCC in mid-adulthood. As these are their most productive years of life, HCC accounts for a substantial burden on the health-care system and drain of productive capacity in the low-income and middle-income countries most affected by HCV and HBV infections. Environments with disparate resource levels require different strategies for the optimal management of HCC. In high-resource environments, guidelines from the American Association for the Study of Liver Diseases or European Association for the Study of the Liver should be applied. In intermediate-resource or low-resource environments, the fundamental focus should be on primary prevention of HCC, through universal HBV vaccination, taking appropriate precautions and antiviral treatments. In intermediate-resource and low-resource environments, the infrastructure and capacity for abdominal ultrasonography, percutaneous ethanol injection, radiofrequency ablation and surgical resection should be established. Programs to provide targeted therapy at low cost, similar to the approach used for HIV therapy in the developing world, should be pursued.

Chronic hepatitis B and hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world and the third leading cause of cancer-related deaths. More than 80% of HCC cases are from the Asian and African continents, and more than 50% of cases are from mainland China. Approximately 350 million to 400 million persons are chronically infected with hepatitis B virus (HBV), and this virus is the most common cause of HCC worldwide. It is estimated that more than 50% of liver cancers worldwide are attributable to HBV and up to 89% of HBV-related HCC are from developing countries. Recently, increasing trends in HCC incidence have been reported from several Western countries, including France, Australia, and the United States.

[Role of environmental factors in the etiology of hepatocellular carcinoma]

Chronic B and C virus hepatitis (HBV and HCV) are the most important risk factors in the development of hepatocellular carcinoma (HCC). About 40-50% of HCC is induced by these two chronic viral infections. Prevalence of HCC is slowly increasing in the United States and in Western-Europe, whereas alcohol consumption is gradually decreasing in the majority of these countries. However, the most important environmental risk factor for HCC is still the heavy long-term alcohol use. The risk of cirrhosis and HCC increases linearly, wherever ethanol intake is greater than 60 g/day for men and women. Aflatoxin, which contaminates grains, mostly in China and Africa, is a well-known mycotoxin. Since geographical distribution of aflatoxin as well as HBV overlaps with each other, they have a synergistic effect on inducing HCC. Cigarette smoking has also hepatocarcinogenic effect, which is significantly enhanced by the concomitant alcohol use or chronic viral hepatitis. Obesity, non-alcoholic fatty liver and steatohepatitis as well as diabetes mellitus together also form a significant risk for HCC, due to the gradually increasing number of patients. Insulin resistance and oxidative stress are the major pathogenetic mechanisms leading to hepatic cell injury in these patients. Oral contraceptive drugs may also play a role in the development of HCC. The long-term exposure to organic solvents is also a risk factor for HCC. Dietary antioxidants, selenium, statins and coffee drinking have protective effect against HCC.

Hepatitis C transmission, prevention, and treatment knowledge among patients with HIV

OBJECTIVE

Liver disease associated with hepatitis C virus (HCV) is a serious cause of mortality among people living with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) (PLWHA). Little is known about the HCV knowledge of PLWHA.

METHODS

One hundred seventy-nine patients at an infectious disease clinic were interviewed on HCV knowledge and alcohol use.

RESULTS

Sixty-six percent of participants indicated that HCV is transmitted through blood; 53% indicated that persons with HIV-HCV co-infection can benefit from HCV treatment; and 79% and 74%, respectively, indicated that safer sex and safer injection techniques can prevent HCV transmission. Among PLWHA with self-reported HCV, 97% indicated that persons with HCV should not drink alcohol, but 32% reported using alcohol in the past 30 days.

CONCLUSIONS

Health education is needed to prevent HCV infections and increase HCV treatment-seeking. Higher education levels were related to more accurate HCV knowledge, indicating the need for health promotion for PLWHA of lower education levels.

Current management of hepatocellular cancer

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver, being the fifth most frequent cancer worldwide. It usually occurs in the setting of chronic liver disease and has a poor prognosis if untreated. Following the diagnosis, this disease requires multidisciplinary management. Orthotopic liver transplantation is theoretically the best treatment for early, unresectable HCC. However, the major practical obstacle is the extreme shortage of organs, which makes this a practical option only in selected patients. In this report we describe new advancements in diagnosis, classification, and treatment that have emerged in the field of HCC in recent years.

[Combined interferon, ribavirin treatment and the occurrence of hepatocellular carcinoma]

Hepatocellular carcinoma (HCC) is the sixth most common cause of cancer-related death worldwide. Primary hepatocellular carcinoma can be found most frequently (80-90%) in patients with liver cirrhosis. The most frequent causes of liver cirrhosis are chronic hepatitis B and C virus infections and chronic alcohol consumption. The treatment and elimination of the etiological factors decreases the risk of HCC. The authors summarize the literary data, where effect of modern antiviral treatment has been examined according to the occurrence of HCC. It can be stated, that the antiviral therapy (interferon and nucleoside analogues) is able to decrease the risk of HCC or the recurrence of the tumor after curative treatment of HCC, in case of non responder state, as well. Drugs used for the insurance of equilibrium in redox state can also help in the decrease of HCC risk.

Risk of malignant neoplasms of liver and biliary tract in diabetic patients with different age and sex stratifications

We prospectively investigated 615,532 diabetic patients and 614,871 age-matched and sex-matched control subjects selected from National Health Insurance claims for malignant neoplasms of liver and biliary tract (International Statistical Classification of Diseases and Related Health Problems, 9th edition, codes 155 and 156, respectively) between 2000 and 2006. The person-year approach with Poisson assumption was used to estimate the hazard rates. We also evaluated the age-specific and sex-specific relative risks of these two malignancies in relation to diabetes with Cox proportional hazard regression model with adjustment for potential confounders. The overall hazard rate of malignant neoplasm of the liver was 32.76 and 17.41 per 10,000 patient-years, respectively, for diabetic men and women; the corresponding figures for biliary tract neoplasm were much lower at 1.42 and 1.60 per 10,000 patient-years. Compared with control subjects, diabetic patients had a two-fold increased risk of malignant neoplasm of the liver, but this risk was attenuated by adjusting for selected clinical risk factors (hazard ratio [HR] 1.21; 95% confidence interval [CI] 1.17-1.25). Additionally, diabetic patients were associated with increased risk of biliary neoplasms with an approximate magnitude of 20%-30%, but the HR was attenuated and became insignificant after adjustment for clinical risk factors (HR 1.07; 95% CI 0.95-1.21). Diabetic patients with cirrhosis had the highest relative risk of liver neoplasm (HR 85.25; 95% CI 76.84-94.58), whereas those with cholangitis had the highest risk of biliary tract neoplasm (HR 70.30; 95% CI 51.95-95.12) compared with control subjects without any clinical risk factors.

CONCLUSION

This population-based study confirms the association of diabetes with liver neoplasm and suggests that diabetic patients with certain clinical risk factors should be educated for strict adherence of liver neoplasm screening.

[Hepatocellular carcinoma: occurrence, risk factors, biomarkers]

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death worldwide. Primary hepatocellular carcinoma can be found most frequently (80-90 %) in patients with liver cirrhosis. The most frequent causes of liver cirrhosis are chronic hepatitis B and C virus infections and chronic alcohol consumption. The occurrence of hepatocellular carcinoma is about 3-15 % in patients with alcoholic liver disease. Other predisposing causes can be: non-alcoholic steatohepatitis (NASH), obesity, diabetes mellitus, autoimmune hepatitis, intrahepatic biliary inflammations (primary biliary cirrhosis, primary sclerosing cholangitis), copper and iron metabolic diseases (Wilson-disease, haemochromatosis), congenital alpha-1-antitripsin deficiency. The causative role of hepatitis B és C viruses have been well established in the pathogenesis of liver cancer. Other pathogenic factors are smoking, and different chemical agents. Treatment options for these patients have previously been limited to best supportive care and palliative therapy. Beside surgical treatment (resection, liver transplantation) the invasive radiologic therapy also has been widely used. The effectiveness of targeted therapy with monoclonal antibodies or small-molecule kinase inhibitors has now been demonstrated for the treatment of different tumors. In year 2007, sorafenib, a multitargeted kinase inhibitor was introduced to clinical practice and found to prolong survival significantly for patients with advanced HCC.

Behaviour does not fully explain the high risk of chronic liver disease in less educated men in Hungary

BACKGROUND

Hungary has among the highest mortality rates from chronic liver disease (CLD) and cirrhosis in Europe. Usually, conventional behavioural factors are hypothesized as the cause of the high risk of CLD.

METHODS

A case-control study was performed with 287 cases and 892 controls to study the relationship between socio-economic and behavioural factors and the risk of CLD. Liver disease was verified by physical examination and blood tests. Blood samples were collected for detecting hepatitis B, C and E virus infection. Information on exposure factors was recorded by the participating physicians and by self-administered questionnaire. Simple regression analysis was used to study the relationship between CLD/cirrhosis and potential risk factors as alcohol intake (amount and source), problem drinking, cigarette smoking, physical activity, viral hepatitis infections, socio-economic factors (education, financial and marital status). Multiple regression analysis was used to identify whether the effect of socio-economic factors is fully mediated by health behaviour (smoking, alcohol consumption, physical activity).

RESULTS

The univariate analysis showed that heavy alcohol consumption, problem drinking, former and heavy cigarette smoking, single, separated or divorced marital status, bad or very bad perceived financial status and lower education significantly increased the risk of CLD/cirrhosis. The effect of marital status and of education did not change after adjustment for behavioural factors, but the effect of perceived financial status disappeared.

CONCLUSIONS

The effect of low socio-economic status on the risk of CLD/cirrhosis is only partially explained by conventional behavioural risk factors in Hungary.

Chronic hepatitis C increased the mortality rates of patients with hepatocellular carcinoma and diabetes mellitus in a triple hepatitis virus endemic community

BACKGROUND

To elucidate the factors associated with mortality rates among older subjects with hepatocellular carcinoma (HCC) and diabetes mellitus (DM) in a triple hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis delta virus (HDV) endemic community.

METHODS

A total of 2,909 residents aged>or=45 years were screened for hepatitis B surface antigen (HBsAg), antibodies to HCV (anti-HCV) and alanine aminotransaminase (ALT) in 1997. Anti-HDV was detected in HBsAg-positive subjects. Those who expired from HCC and DM were identified from official mortality data sets (1997-2003). Survival was analyzed using the Kaplan-Meier survival curve with log-rank test and the Cox proportional hazard model.

RESULTS

Forty-one patients died of HCC and 25 of DM during the study period. Multivariate analysis indicated that age>or=65 years (hazard ratio 3.4; 95% confidence interval 1.8-6.4), HBsAg (3.3; 1.7-6.7), anti-HCV (3.8; 1.7-8.5) and ALT>or=40 IU/L (3.7; 1.9-7.0) were independent predictors of HCC mortality, while age>or=65 years (4.8; 2.1-11.0) and anti-HCV (4.2; 1.7-10.6) were two independent predictors of DM mortality. There were synergistic effects of dual viral infections for HCC, but not for DM mortality.

CONCLUSIONS

Old age and chronic HCV infection increase the risk of HCC and DM mortality. HBsAg and ALT levels are also risk factors for HCC mortality, but not DM. The synergistic effects of dual hepatitis viral infections are demonstrable and warrant further investigation.

Association of diabetes duration and diabetes treatment with the risk of hepatocellular carcinoma

BACKGROUND

Despite the observed association between diabetes mellitus and hepatocellular carcinoma (HCC), little is known about the effect of diabetes duration before HCC diagnosis and whether some diabetes medications reduced the risk of HCC development. This objective of the current study was to determine the association between HCC risk and diabetes duration and type of diabetes treatment.

METHODS

A total of 420 patients with HCC and 1104 healthy controls were enrolled in an ongoing hospital-based case-control study. Multivariate logistic regression models were used to adjust for HCC risk factors.

RESULTS

The prevalence of diabetes mellitus was 33.3% in patients with HCC and 10.4% in the control group, yielding an adjusted odds ratio (AOR) of 4.2 (95% confidence interval [95% CI], 3.0-5.9). In 87% of cases, diabetes was present before the diagnosis of HCC, yielding an AOR of 4.4 (95% CI, 3.0-6.3). Compared with patients with a diabetes duration of 2 to 5 years, the estimated AORs for those with a diabetes duration of 6 to 10 years and those with a diabetes duration >10 years were 1.8 (95% CI, 0.8-4.1) and 2.2 (95% CI, 1.2-4.8), respectively. With respect to diabetes treatment, the AORs were 0.3 (95% CI, 0.2-0.6), 0.3 (95% CI, 0.1-0.7), 7.1 (95% CI, 2.9-16.9), 1.9 (95% CI, 0.8-4.6), and 7.8 (95% CI, 1.5-40.0) for those treated with biguanides, thiazolidinediones, sulfonylureas, insulin, and dietary control, respectively.

CONCLUSIONS

Diabetes appears to increase the risk of HCC, and such risk is correlated with a long duration of diabetes. Relying on dietary control and treatment with sulfonylureas or insulin were found to confer the highest magnitude of HCC risk, whereas treatment with biguanides or thiazolidinediones was associated with a 70% HCC risk reduction among diabetics.

Management of nonresponsive hepatitis C

More than 50% of hepatitis C virus (HCV)-infected patients do not respond to the classical pegylated interferon (PEG-IFN)/ribavirin combination therapy. However, failing to respond to one course of treatment is not synonymous of therapy failure and retreatment is often beneficial. Alternative retreatment strategies include repeating the classical standard of care with an optimized drug regimen and adherence, including ribavirin serum concentration adjustment, correcting, if at all possible, comorbidities, and the addition of new specific anti-HCV molecules to the backbone of pegylated interferon/ribavirin. Options of retreatment should include consensus and natural interferons. For patients with advanced disease exposed to a high risk of lethal complications, customized maintenance therapy could be an effective option since it may slow down complications in some patients. Since low-dose interferon monotherapy is not sufficient, such a maintenance therapy remains to be verified via clinical trials. New possibilities of noninvasive assessment of fibrosis and the use of genetic tests to predict fibrosis progression and responsiveness to interferon are major emerging opportunities that run parallel to the revolution of the pharmacologic armentarium.

Mechanisms of HBV-related hepatocarcinogenesis

The hepatitis B virus (HBV) is a small enveloped DNA virus, which primarily infects hepatocytes and causes acute and persistent liver disease. Epidemiological studies have provided overwhelming evidence for a causal role of chronic HBV infection in the development of hepatocellular carcinoma, but the molecular mechanisms underlying virally-induced tumourigenesis remain largely debated. In the absence of a dominant oncogene encoded by the HBV genome, indirect roles have been proposed, including insertional activation of cellular cancer-related genes by HBV DNA integration, induction of genetic instability by viral integration or by the regulatory protein HBx, and long-term effects of viral proteins in enhancing immune-mediated liver disease. Recent genetic studies indicate that HBV-related tumours display a distinctive profile with a high rate of chromosomal alterations and low frequency of beta-catenin mutations. This review will discuss the evidence implicating chronic HBV infection as a causal risk factor of primary liver cancer. It will also discuss the molecular mechanisms that are critical for the tumourigenic process due to long lasting infection with HBV.

Alcohol and HCV chronic infection are risk cofactors of type 2 diabetes mellitus for hepatocellular carcinoma in Italy

Type 2 diabetes mellitus (DM2) has been associated with hepatocellular carcinoma (HCC) development. To study this relationship, we enrolled 465 HCC patients compared with 618 Cirrhotic cases and 490 Controls. The prevalence of DM2 is significantly higher in HCC patients with an Odds Ratio of 3.12 versus Controls. In HCC cases with alcohol abuse, the frequency of DM2 is the highest. In our HCC patients, when HCV infection is associated with alcohol abuse, the liver cancer develops earlier. In addition, multivariate analysis shows that alcohol consumption is an independent risk factor for HCC more relevant than HCV infection.

Reduced CRYL1 expression in hepatocellular carcinoma confers cell growth advantages and correlates with adverse patient prognosis

Homozygous deletion screening has been widely utilized to define tumour suppressor genes (TSGs) in cancers. Although these biallelic deletions are infrequent, their identification has facilitated the discovery of many important TSGs. We have systematically examined the genome of hepatocellular carcinoma (HCC), a highly malignant tumour that is rapidly fatal, for the presence of homozygous deletions. Array-CGH analysis on early passage of HCC cultures and cell lines led us to identify six homozygous deleted (HD) regions. A high concordance between array-CGH and expression of HD genes was demonstrated, where crystallin Lambda1 (CRYL1; located on chromosome 13q12.11) displayed the most frequent down-regulation. We found that reduced mRNA expression of CRYL1 was common in HCC tumours when compared with their adjacent non-tumoural liver (p = 0.0097). Significant associations could also be drawn between repressed CRYL1 and advanced tumour staging, increased tumour size, and shorter disease-free survival of patients (p < 0.037). Moreover, homozygous deletions on CRYL1 could be detected in 36% of HCC cases, where recurrent HDs were identified on exons 1, 5, and 8. Examination of other causal events suggested histone deacetylation and promoter hypermethylation to be likely inactivating mechanisms as well. Re-expression of CRYL1 in the SK-Hep1 cell line, where biallelic loss of CRYL1 was found, induced profound inhibition of cellular proliferation and cell growth (p < 0.0015). By Annexin V staining, CRYL1 restoration readily increased pro-apoptotic cells with an induction of PARP cleavage. Flow cytometry further revealed that CRYL1 could prolong the G(2)-M phase, possibly through interruption of the Cdc2/cyclin B pathway. Given that regional chromosome 13q12-q14 loss is a causal genomic event in HCC tumourigenesis, our finding may have implications for identifying a novel TSG CRYL1 within this important locus.

Alcohol, nutrition and liver cancer: Role of Toll-like receptor signaling

This article reviews the evidence that ties the development of hepatocellular carcinoma (HCC) to the natural immune pro-inflammatory response to chronic liver disease, with a focus on the role of Toll-like receptor (TLR) signaling as the mechanism of liver stem cell/progenitor transformation to HCC. Two exemplary models of this phenomenon are reviewed in detail. One model applies chronic ethanol/lipopolysaccharide feeding to the activated TLR4 signaling pathway. The other applies chronic feeding of a carcinogenic drug, in which TLR2 and 4 signaling pathways are activated. In the drug-induced model, two major methyl donors, S-adenosylmethionine and betaine, prevent the upregulation of the TLR signaling pathways and abrogate the stem cell/progenitor proliferation response when fed with the carcinogenic drug. This observation supports a nutritional approach to liver cancer prevention and treatment. The observation that upregulation of the TLR signaling pathways leads to liver tumor formation gives evidence to the popular concept that the chronic pro-inflammatory response is an important mechanism of liver oncogenesis. It provides a nutritional approach, which could prevent HCC from developing in many chronic liver diseases.

Neither diabetes mellitus nor overweight is a risk factor for hepatocellular carcinoma in a dual HBV and HCV endemic area: community cross-sectional and case-control studies

OBJECTIVES

Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are well-known risk factors for hepatocellular carcinoma, and diabetes mellitus (DM) and overweight have also been reported as risk factors for hepatocellular carcinoma (HCC). We tried to elucidate the roles of DM and overweight in HCC development in a dual HBV and HCV endemic area of southern Taiwan.

METHODS

In 2004, a community-based comprehensive screening program was conducted in Tainan County. Hepatitis B surface antigen (HBsAg), anti-HCV, alpha-fetoprotein, complete blood counts, triglyceride, cholesterol, and glucose levels were examined. DM was defined as fasting blood sugar >126 mg per 100 ml, and overweight was defined as a body mass index >24 kg m(-2). Subjects with thrombocytopenia (platelet count <150 x 10(9) l(-1)) and elevated alpha-fetoprotein (>20 ng ml(-1)) underwent ultrasonographic screening for HCC. A total of 56,307 adults (>40 years old) participated, and 72 new HCC cases were detected and confirmed.

RESULTS

In comparisons of all 72 HCC cases with the other 144 individual age-, sex-, residency-, HBsAg-, and anti-HCV-matched controls, only thrombocytopenia and high alanine transaminase (ALT) levels were shown to be independent risk factors. Neither DM nor overweight was shown to be significant in any of the analyses.

CONCLUSIONS

On the basis of the community-based cross-sectional and case-controlled studies, neither DM nor overweight was a risk factor for HCC in a dual HBV and HCV endemic area. However, male gender, age (> or =65 years), HBsAg, anti-HCV, thrombocytopenia, and high ALT levels were independent risk factors for HCC.

Diabetes and hepatocellular carcinoma: what role does diabetes have in the presence of other known risk factors?

Known risk factors for hepatocellular carcinoma (HCC) include hepatitis C, hepatitis B, and alcoholic liver disease. Several studies have examined diabetes as a risk factor for HCC because of its association with fatty liver disease and non-alcoholic steatohepatitis. The current study by Tung et al. found that neither diabetes nor overweight was a risk factor for HCC. Results were consistent using both a cross-sectional and a case-control study approach. Findings from this study suggest that diabetes and overweight alone are not adequate to increase the risk of HCC in the absence of concomitant viral hepatitis or liver disease.

Hepatitis B and C virus-related carcinogenesis

Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are the most important causes of hepatocellular carcinoma (HCC), accounting for the majority of the cases worldwide. The geographical distribution of HCC therefore coincides with the distribution of HBV and HCV infections in those areas. Similar to nonviral liver diseases, HBV and HCV infection can cause chronic injury to the liver, with subsequent progression to severe fibrosis and cirrhosis. The presence of cirrhosis is a major risk factor for the development of HCC. However, HCC can occur in the absence of cirrhosis, suggesting that both HBV and HCV may be directly involved in hepatocarcinogenesis. Several HBV factors have been implicated in hepatocarcinogenesis, including the HBx gene, the pre-S2/S gene and the HBV spliced protein. Furthermore, HBV can be integrated into the host genome, leading to changes in genomic function or chromosomal instability. By contrast to HBV, HCV cannot integrate into the host genome. Various HCV proteins, including the core, envelope and nonstructural proteins, have been shown to have oncogenic properties. For HBV infection, antiviral therapy and vaccination have been shown to decrease the risk of HCC. Antiviral therapy for HCV can also reduce the risk of HCC.

Risk of HCC: genetic heterogeneity and complex genetics

Hepatocellular carcinoma (HCC) is a common form of cancer that arises from hepatocytes and whose risk may be affected by several known environmental factors, including hepatitis viruses, alcohol, cigarette smoking, and others. Rare monogenic syndromes, such as alpha1-antitrypsin deficiency, glycogen storage disease type I, hemochromatosis, acute intermittent and cutanea tarda porphyria, as well as hereditary tyrosinemia type I are associated with a high risk of HCC. Several common conditions or diseases inherited as polygenic traits e.g. autoimmune hepatitis, type 2 diabetes, a family history of HCC, hypothyroidism, and non-alcoholic steatohepatitis also show an increased risk of HCC compared to the general population. Overall, the genetic susceptibility to HCC is characterized by a genetic heterogeneity; a high individual risk of HCC may thus be caused by several unlinked single gene defects, whose carriers are rare in the general population, or by more common conditions inherited by complex genetics.

Influence of anti-HBc seropositivity on the risk of hepatocellular carcinoma in HCV-infected patients after adjusting for confounding factors

It is controversial whether past hepatitis B virus infection constitutes an additional risk of hepatocellular carcinoma (HCC) among patients with hepatitis C virus (HCV). The incidence of HCC between 1994 and 2004 was analysed among 1262 patients who were only positive for HCV. The cumulative incidence of HCC was assessed by Kaplan-Meier analysis and the difference between two groups was assessed by the log-rank test. The effect of anti-HBc positivity on the risk of HCC was assessed with multivariate Cox proportional analysis. Anti-HBc was positive in 522 (41.4%) patients. The proportion of male patients (56.7 vs 46.8%, P < 0.001) and mean age (60.8 vs 56.9 years, P < 0.001) were significantly higher in the anti-HBc positive group. HCC developed in 339 patients (mean follow-up 7.0 years), with cumulative incidence rates at 3, 5 and 10 years of 12.7, 24.5 and 41.9% in the anti-HBc positive group and 10.6, 17.7 and 33.4% in the negative group, respectively (P = 0.005). However, anti-HBc seropositivity did not reach statistical significance in multivariate analysis including age and gender (hazard ratio, 1.06; 95% CI, 0.85-1.31; P = 0.63). Anti-HBc positivity and HCC incidence were confounded by male gender and older age.

Etiology of hepatocellular carcinoma in Latin America: a prospective, multicenter, international study

BACKGROUND/AIMS

No prospective study has been published investigating etiology of HCC in Latin America. The primary aim of this prospective study was to analyze the etiology of liver disease in patients with HCC from our area. Secondary aims were to evaluate staging using Okuda and BCLC classifications; and percentage of patients receiving treatment.

METHODS

The Governing Board of the Latin American Association for the Study of the Liver designed the protocol. During a 18 month period, all members were invited to load their incident HCC cases on line.

RESULTS

240 cases from 9 countries were uploaded, 174 were male (72.5%), median age was 64 years, interquartile range 57-72. In 85.4% of cases, patients had underlying cirrhosis. Main etiological factors were: HCV in 74 patients (30.8%), alcohol in 49 (20.4%), cryptogenic cirrhosis in 35 (14.6%), HBV in 26 (10.8%), HCV plus alcohol in 14 (5.8%). Considering the combinations, hepatitis C was shown in 91 patients (38%); chronic alcoholism in 68 patients (28%); and hepatitis B in 33 patients (14%). There were no significant differences between the groups in the age at diagnosis. Percentage of male gender was higher in groups of alcohol (94%), HCV plus alcohol (93%) and HBV (85%) than in cryptogenic cirrhosis (60%) and HCV (59%) (p<0.001).

CONCLUSIONS

Our prospective study showed that hepatitis C is the more frequent etiology of HCC in Latin America, followed by alcoholic cirrhosis. Demographical results showed a male predominance (male:female ratio 2.6) with an important proportion of patients being diagnosed at their sixties.

Hepatitis B virus preS2 gene-specific locked nucleic acid antisense oligonucleotides significantly inhibit hepatitis B virus replication and expression in HepG2 2.2.15 cells

AIM: To investigate the inhibitory effects of hepatitis B virus (HBV) preS2 gene-specific locked nucleic acid (LNA) antisense oligonucleotides on HBV replication and expression in HepG2 2.2.15 cells.

METHODS: Three LNA antisense oligonucleotides of different lengths that are complementary to the translation initiation region of the HBV preS2 gene were designed, synthesized and introduced into HepG2 2.2.15 cells by cationic liposome-mediated transfection. Hepatitis B surface antigen (HbsAg) and HBV DNA levels in cell supernatant were tested by time-resolved immunofluorescence assay (TRFIA) and fluorescent quantitative-polymerase chain reaction (FQ-PCR). The inhibitory effects of different antisense oligonucleotides on HBV DNA replication and expression were compared. The cell toxicity of LNA antisense oligonucleotides was evaluated by methyl thiazolyl tetrazolium (MTT) assay.

RESULTS: On day 1 after transfection with LNA antisense oligonucleotides, the expression of HBsAg and the replication of HBV DNA were inhibited. On day 7, the reduced rates of HBsAg and HBV DNA levels were 45.79%, 52.92% and 67.21% as well as 35.15%, 40.69% and 52.16% in the non-modified antisense oligonucleotide group, all-phosphorothioate-modified antisense oligonucleotide group and LNA antisense oligonucleotide group, respectively. LNA antisense oligonucleotides showed the strongest inhibitory effects on viral activity and had no impact on cell metabolism. Compared with the control group, the reduced rates of HBsAg and HBV DNA levels achieved in each of the above groups were significantly higher (all P < 0.01). Moreover, the reduced rates of HBsAg and HBV DNA levels in the LNA antisense oligonucleotide group were significantly higher than those in other antisense oligonucleotide groups (all P < 0.05).

CONCLUSION: LNA antisense oligonucleotides targeting the preS2 gene can effectively inhibit the replication and expression of HBV in vitro. The preS2 gene can be used as an effective target for gene therapy of HBV infection.

Metabolic syndrome and hepatocellular carcinoma: two growing epidemics with a potential link

Hepatocellular carcinoma (HCC) is the most rapidly increasing cause of cancer death in the United States. Although many risk factors for HCC are well defined, including hepatitis B virus (HBV), hepatitis C virus (HCV), and alcohol, most series have indicated that 5% to 30% of patients with HCC lack a readily identifiable risk factor for their cancer. The majority of "cryptogenic" HCC in the United States is attributed to nonalcoholic fatty liver disease (NAFLD), a hepatic manifestation of the metabolic syndrome. The metabolic syndrome is a constellation of problems that includes insulin resistance, obesity, hypertension, and hyperlipidemia. Increasingly, components of the metabolic syndrome are being linked to various forms of cancer with respect to both increased risk of disease and worsened outcome. In this review, the authors focused on the relation between metabolic syndrome and HCC. They investigated the increased risks of HCC among individuals with features of metabolic syndrome, potentially worsened cancer outcomes in these patients, possible pathogenic mechanisms to explain these relations, and treatment options for those with NAFLD and its progressive counterpart, nonalcoholic steatohepatitis. It is predicted that metabolic syndrome will lead to large increases in the incidence of HCC over the next decades. A better understanding of the relation between these 2 diseases ultimately should lead to improved screening and treatment options for patients with HCC.

Antiviral effects of locked nucleic acid antisense oligonucleotides targeting HBV S gene mRNA in HepG2 2.2.15 cells

AIM: To investigate the inhibitory effects of locked nucleic acid (LNA) antisense oligonucleotides targeting hepatitis B virus (HBV) S gene in HepG2 2.2.15 cells, and screen effective LNA antisense oligonucleotides.

METHODS: Four LNA antisense oligonucleotides of different lengths that are complementary to the translation initiation region of HBV S gene were designed, synthesized, and introduced into HepG2 2.2.15 cells by cationic liposome-mediated transfection. Hepatitis B surface antigen (HBsAg) and HBV DNA levels in cell supernatant were tested by enzyme-linked immunosorbent assay (ELISA) and fluorescent quantitative-polymerase chain reaction (FQ-PCR) 24, 48 and 72 h after transfection. The cell toxicity of LNA antisense oligonucleotides was detected by methyl thiazolyl tetrazolium (MTT) assay.

RESULTS: All four LNA antisense oligonucleotides (10, 15, 20 and 25 base, respectively) could inhibit the expression of HBsAg and the replication of HBV DNA. Seventy-two hours after transfection, the reduced rates of HBsAg and HBV DNA levels were 46.58%, 54.38%, 72.43% and 69.92% as well as 27.09%, 28.77%, 34.71% and 32.68%, respectively. No obvious cell toxicity of LNA antisense oligonucleotides was noted.

CONCLUSION: LNA antisense oligonucleotides targeting HBV S gene show strong inhibitory effects on HBV replication in vitro. The optimal length of LNA antisense oligonucleotides ranges from 15 to 25 base. LNA antisense oligonucleotides targeting HBV S gene have a therapeutic potential in patients infected with HBV.

Management of hepatocellular carcinoma in Asia: consensus statement from the Asian Oncology Summit 2009

Asia has a disproportionately large share of the world's hepatocellular carcinoma (HCC), mainly because of the endemic status of chronic hepatitis B and C viruses, which leads to liver cirrhosis and an increased risk of HCC. This etiological factor presents important opportunities for prevention, early detection, diagnosis, and treatment of HCC. This consensus statement reviews the available medical evidence for management of HCC in Asia, and gives treatment recommendations that are adapted to resource availability in this diverse region with disparate health-care delivery systems.

Diabetes mellitus as a risk factor for gastrointestinal cancer among American veterans

AIM

To assess the risk of biliary and pancreatic cancers in a large cohort of patients with type 2 diabetes mellitus (DM).

METHODS

Eligibility for this study included patients with type 2 DM (ICD-9 code 250.0) who were discharged from Department of Veteran Affairs hospitals between 1990 and 2000. Non-matched control patients without DM were selected from the same patient treatment files during the same period. Demographic information included age, sex and race. Secondary diagnoses included known risk factors based on their ICD-9 codes. By multivariate logistic regression, the occurrence of biliary and pancreatic cancer was compared between case subjects with DM and controls without DM.

RESULTS

A total of 1,172,496 case and control subjects were analyzed. The mean age for study and control subjects was 65.8+/-11.3 and 64.8+/-12.6 years, respectively. The frequency of pancreatic cancer in subjects with DM was increased (0.9%) in comparison to control subjects (0.3%) with an OR of 3.22 (95% CI: 3.03-3.42). The incidence of gallbladder and extrahepatic biliary cancers was increased by twofold in diabetic patients when compared to controls. The OR and 95% CI were 2.20 (1.56-3.00) and 2.10 (1.61-2.53), respectively.

CONCLUSION

Our study demonstrated that patients with DM have a threefold increased risk for developing pancreatic cancer and a twofold risk for developing biliary cancer.

Serum alpha-fetoprotein levels during and after interferon therapy and the development of hepatocellular carcinoma in patients with chronic hepatitis C

The association between serum alpha-fetoprotein (AFP) levels during and after interferon (IFN) therapy and the development of hepatocellular carcinoma (HCC) was evaluated in patients with chronic hepatitis C (CHC). A total of 263 patients treated by IFN with or without ribavirin were enrolled in the study. Serum AFP levels during and after IFN therapy were investigated retrospectively, and statistical analysis was performed to identify the factors associated with HCC development. During IFN therapy, serum AFP levels significantly decreased, regardless of virologic response to treatment. Increased serum AFP levels (>or=10 ng/ml) at the end of IFN therapy (EOT) was a close-to-significant variable affecting the development of HCC (P = 0.057), and a significantly higher cumulative incidence of HCC was seen in patients with increased serum AFP levels at EOT (P = 0.021). Serum AFP level at EOT is a possible predictor of HCC in CHC patients after IFN therapy.

Meta-analysis of epidemiologic studies on cigarette smoking and liver cancer

BACKGROUND

Whereas the International Agency for Research on Cancer (IARC) Monograph concluded that the evidence for the relationship between cigarette smoking and liver cancer is sufficient, the US Surgeon General's report summarized the data as suggestive but not sufficient.

METHODS

A meta-analysis of previous epidemiologic studies may help to clarify the potential association. We identified 38 cohort studies and 58 case-control studies in a systematic literature search for studies on liver cancer and cigarette smoking. The meta-relative risk (mRR) of liver cancer and dose-response trends were calculated. Tests for heterogeneity, publication bias assessment and influence analyses were performed.

RESULTS

Compared with never smokers, the adjusted mRR was 1.51 [95% confidence interval (CI) 1.37-1.67] for current smokers and 1.12 (95% CI 0.78-1.60) for former smokers. The increased liver cancer risk among current smokers appeared to be consistent in strata of different regions, study designs, study sample sizes and publication periods.

CONCLUSION

The results of our meta-analysis show that tobacco smoking is associated with liver cancer development, which supports the conclusion by the IARC Monograph. This conclusion has an important public health message for areas with high smoking prevalence and high liver cancer incidence such as China.

HBV S gene-specific antisense locked nucleic acid significantly inhibits HBV replication and expression in HBV transgenic mice

AIM: To investigate the inhibitory effects of hepatitis B virus (HBV) S gene-specific antisense locked nucleic acid (LNA) on HBV replication and expression.

METHODS: Thirty HBV transgenic mice were randomly divided into five groups (n = 6): glucose (5% GLU solution) control group, empty liposome control group, LNA group, S-ASODN-liposome group and LNA-liposome group. Antisense LNA was injected into mice via the tail vein. Serum HBsAg was quantified by ELISA. Serum HBV DNA was quantified by PCR. The expression of HBsAg in the liver was detected by immunohistochemistry. Serum ALB, ALT, BUN, CR, ApoA1 and ApoB were measured using an automatic biochemical analyzer. The effects of antisense LNA on mouse organs were investigated by HE staining of mouse liver and kidney sections.

RESULTS: On days 1, 3, 7 and 14 after LNA injection, serum HBsAg levels in the LNA-liposome group were reduced by 41.7%, 52.8%, 57.8% and 30.5%, respectively, while serum HBV DNA expression levels were decreased by 18.5%, 36.1%, 52.9% and 32.7%, respectively. These values were significantly higher than those in the control groups (all P < 0.05). No significant differences were noted in serum ALB, ALT, BUN, CR, ApoA1 and ApoB between the experiment group and the control groups (all P > 0.05). The expression level of HBsAg in the liver in the LNA-liposome group was significantly lower than those in the control groups. No significant histological abnormalities were found in the liver in all groups.

CONCLUSION: HBV S gene-specific antisense LNA can significantly inhibit the replication and expression of HBV.

Alcoholic liver disease and hepatitis C: A frequently underestimated combination

Alcoholic liver disease (ALD) and hepatitis C virus (HCV) infection represent, either alone or in combination, more than two thirds of all patients with liver disease in the Western world. This review discusses the epidemiology and combined impact of ALD and HCV on the progression of liver disease. ALD and HCV affect the progression of liver disease to liver cirrhosis and hepatocellular carcinoma (HCC) in a synergistic manner. Thus, the risk for HCC increases five times with a daily alcohol consumption of 80 g; in the presence of HCV it is increased 20-fold, and a combination of both risk factors leads to a more than 100-fold risk for HCC development. Alcohol consumption also decreases the response to interferon treatment which is probably due to a lack of compliance than a direct effect on HCV replication. Several molecular mechanisms are discussed that could explain the synergistic interaction of alcohol and HCV on disease progression. They include modulation of the immune response and apoptosis, increased oxidative stress via induction of CYP2E1 and the hepatic accumulation of iron. Thus, both HCV and alcohol independently cause hepatic iron accumulation in > 50% of patients probably due to suppression of the liver-secreted systemic iron hormone hepcidin. A better understanding of hepcidin regulation could help in developing novel therapeutic approaches to treat the chronic disease in the future. For now, it can be generally concluded that HCV-infected patients should abstain from alcohol and alcoholics should be encouraged to participate in detoxification programs.

Current management strategy of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) still remains a considerable challenge for surgeons. Surgery, including liver transplantation, is the most important therapeutic approach for patients with this disease. HCC is frequently diagnosed at advanced stages and has a poor prognosis with a high mortality rate even when surgical resection has been considered potentially curative. This brief report summarizes the current status of the management of this malignancy and includes a short description of new pharmacological approaches in HCC treatment.

Metabolic factors and subsequent risk of hepatocellular carcinoma by hepatitis virus infection status: a large-scale population-based cohort study of Japanese men and women (JPHC Study Cohort II)

OBJECTIVE

The association between metabolic factors and hepatocellular carcinoma (HCC) has not been well clarified. We prospectively examined whether metabolic factors predicts the subsequent risk of HCC in the Japan Public Health Center-based Prospective Study Cohort II, in consideration of hepatitis virus infection status.

METHODS

A total of 17,590 subjects aged 40-69 participating in a questionnaire and health checkup survey during 1993-1994 were followed for incidence of HCC through 2006. A total of 102 cases of HCC were newly documented. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated for metabolic factors controlling for potential confounding factors.

RESULTS

The presence of metabolic factors in the aggregate was associated with a significantly increased risk of HCC, especially with hepatitis virus infection. HCC was positively associated particularly with high glucose (HR = 1.75, CI = 1.11-2.74) and overweight (HR = 2.22, CI = 1.42-3.48). Results were similar when analyses were limited to subjects with HCV infection.

CONCLUSIONS

Although metabolic factors in the aggregate may be associated with an increased risk of HCC, the main contributors to this association under HCV infection appear to be overweight and high glucose. Improvement of these factors may be a crucial target in preventing progression to HCC in those with HCV infection.

Targeted therapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. The major etiologies and risk factors for development of HCC are well defined and some steps of hepatocellular carcinogenesis have been elucidated. Despite these scientific advances and the implementation of measures for early detection of HCC in patients who are at risk of this disease, survival of patients has not improved greatly over the past three decades. This situation is partly due to the limited therapeutic options available. While surgery and percutaneous or transarterial interventions are effective for patients with limited or compensated underlying liver disease, more than 80% of patients present with multifocal HCC and/or advanced liver disease, or have comorbidities at the time of diagnosis. Treatment options for these patients have previously been limited to best supportive care. The effectiveness of targeted therapy with monoclonal antibodies or small-molecule kinase inhibitors has now been demonstrated for the treatment of different tumors. In 2007, the multitargeted kinase inhibitor, sorafenib, was found to prolong survival significantly for patients with advanced HCC. This Review discusses the mechanisms of targeted therapies and clinical studies that have investigated these therapies in patients with HCC. Perspectives for future developments are also provided.

Hepatitis B-related hepatocellular carcinoma: epidemiological characteristics and disease burden

Worldwide, 350 million people are chronically infected with hepatitis B virus (HBV) who are at greater risk of hepatocellular carcinoma (HCC) compared with uninfected people. The relative risks of HCC among people infected with HBV ranges from 5 to 49 in case-control studies and from 7 to 98 in cohort studies. More than 50% of HCC cases worldwide and 70-80% of HCC cases in highly HBV endemic regions are attributable to HBV. Incidence of HCC (per 100,000 person/year) among people with chronic HBV infection ranges from 400 to 800 in male and from 120 to 180 in female. Factors associated with increased risk of HCC include demographic characteristics (male sex and older age), lifestyles (heavy alcohol consumption and smoking), viral factors (genotype C, D F, high level of HBV DNA, core/precore mutation) and clinical factors (cirrhosis, elevated alpha-fetoprotein (AFP) and alanine aminotransferase (ALT)). HBV-related HCC has extremely poor prognosis with median survival less than 16 months. Survival rates of HBV-related HCC ranged from 36% to 67% after 1 year and from 15% to 26% after 5 year of diagnosis. Older age, liver function impairment, vascular invasion, tumour aggressiveness and elevated AFP are associated with HCC survival. Global burden of HBV-related liver disease is still a major challenge for public health in the 21st century. While decreases in incidence of HBV infection have been observed in birth cohorts following the introduction of universal infant HBV vaccination programme, HBV-related HCC incidence in is projected to increase for at least two decades because of the high prevalence of chronic HBV infection and prolonged latency to HCC development. To reduce HBV-related HCC continued expansion of universal infant HBV vaccination is required along with antiviral therapy targeted to those individuals at highest risk of HCC. Broad public health strategies should include routine testing to identify chronic HBV infection, improved health infrastructures including human resource to provide diagnosis and treatment assessment.

Role of hepatitis B virus X repression of C/EBPbeta activity in the down-regulation of glutathione S-transferase A2 gene: implications in other phase II detoxifying enzyme expression

1. A genome-wide in silico screening rendered the genes of phase II enzymes in the rat genome whose promoters contain the putative DNA elements interacting with CCAAT/enhancer binding protein (C/EBP) and NF-E2-related factor (Nrf2). The hepatitis B virus X (HBx) protein strongly modulates the transactivation and/or the repression of genes regulated by some bZIP transcription factors. 2. This study investigated the effects of HBx on the induction of phase II enzymes with the aim of elucidating the role of HBx interaction with C/EBPbeta or Nrf2 bZIP transcription factors in hepatocyte-derived cells. 3. Immunoblot and reporter gene analyses revealed that transfection of HBx interfered with the constitutive and inducible GSTA2 transactivation promoted by oltipraz (C/EBPbeta activator), but not that by tert-butylhydroquinone (t-BHQ, Nrf2 activator). Moreover, HBx transfection completely inhibited GSTA2 reporter gene activity induced by C/EBPbeta, but failed to inhibit that by Nrf2. 4. Gel shift assays identified that HBx inhibited the increase in C/EBPbeta-DNA complex formation by oltipraz, but not the increase in Nrf2-DNA complex by t-BHQ. Immunoprecipitation and immunoblot assays verified the direct interaction between HBx and C/EBPbeta. Moreover, chromatin immunoprecipitation assays confirmed HBx inhibition of C/EBPbeta binding to its binding site in the GSTA2 gene promoter. HBx repressed the induction of other phase II enzymes including GSTP, UDP-glucuronyltransferase 1A, microsomal epoxide hydrolase, GSTM1, GSTM2, and gamma-glutamylcysteine synthase. 5. These results demonstrate that HBx inhibits the induction of phase II detoxifying enzymes, which is mediated by its interaction with C/EBPbeta, but not Nrf2, substantiating the specific role of HBx in phase II detoxifying capacity.

Measurement of food and alcohol intake in relation to chronic liver disease

It is well established that the consumption of alcohol is implicated in both the cause and progression of chronic liver disease. The quantity of drink that is consumed, the pattern of drinking and type of alcoholic beverages consumed are all possible factors in disease aetiology. The impact of specific dietary components on the cause and progression of chronic liver disease is unclear although it is known that obesity, and hence the over-consumption of energy, is a predictor of fatty liver. Work to elucidate the role of both diet and alcohol in the aetiology of liver disease is hindered by the methods currently available to measure dietary (including alcohol) intake. The validity and reliability of retrospective methods of assessing diet are limited by their reliance on memory and, for the 24 h recall, the short-time period of intake assessed and its inability to assess variability across the week. Prospective methods which measure food and drink intake at the time of consumption, and include weighed or estimated food diaries, are useful for prospective cohort studies but are expensive and have a high respondent burden. For estimation of alcohol intake retrospectively, the Cognitive Lifetime Drinking questionnaire, which prompts responses using a lifetime calendar, is a useful tool but still depends on memory. More work is required to develop valid, reliable and easily administered tools for measurement of both diet and alcohol.

Hepatocellular carcinoma prevalence and mortality in a male state prison population

OBJECTIVES

The incidence of hepatocellular carcinoma (HCC) in the United States has increased dramatically over the last two decades, largely because of an increase in the number of people with advanced hepatitis C virus (HCV) infection. U.S. prisoners are at high risk for HCC, given their elevated rates of HCV infection, comorbid hepatitis B virus (HBV) infection, and alcoholic liver disease. The purpose of our study was to examine the prevalence and mortality of HCC in the nation's largest state prison system.

METHODS

The study population consisted of 325,477 male Texas Department of Criminal Justice (TDCJ) inmates who were incarcerated between January 1, 2003, and July 31, 2006. Information on medical conditions and demographic characteristics was obtained from an institution-wide medical information system.

RESULTS

During the 3.5-year study period, 176 male TDCJ inmates (54 per 100,000) were diagnosed with HCC and 108 (33 per 100,000) died as a result of HCC. Inmates who were Hispanic, older, and infected with HCV, HBV, or human immunodeficiency virus had elevated rates of both HCC prevalence and mortality. After adjusting for all study covariates, HCC prevalence, but not mortality, was modestly elevated among inmates with diabetes.

CONCLUSIONS

Our study showed that the Texas male prison population had a sevenfold higher prevalence of HCC than the general U.S. male population and a fourfold higher death rate from HCC. These findings likely reflect the high concentration of HCC-related risk factors, particularly HCV, among prisoners.

Factors associated with awareness of infection status among chronic hepatitis B and C carriers in Korea

Hepatitis B (HBV) and hepatitis C (HCV) viral infections are the most important risk factors for hepatocellular carcinoma (HCC), which is responsible for 17.5% of cancer deaths in Korea. The objectives of this study were to identify demographic characteristics that may affect hepatitis carriers' awareness of their infection status, and to assess whether health-related behaviors differed by awareness of the infection. Among 18,636 persons who were recruited from a cancer screenee cohort, 904 were HBV carriers and 146 were HCV carriers. Among the HBV carriers, 74.2% were aware of their infection status. Higher education (odds ratio, 1.8; college versus middle school or less), family history of liver cancer or disease, and marriage were associated with awareness of HBV infection status. Participants who were aware of their HBV carrier status were more likely to be former smokers or drinkers than those who were not aware of their status. Only 34.9% of HCV carriers were aware of their HCV infection status. No demographic characteristics were related to awareness of HCV infection status among HCV carriers. However, HCV carriers who were aware of their infection status were more likely to be former drinkers (odds ratio, 9.2; 95% confidence interval, 1.8-47.2). In conclusion, two thirds of HCV carriers and one fourth of HBV carriers in this study population were not aware of their infection status, and awareness of hepatitis infection status was significantly associated with other risk behaviors, such as alcohol consumption and cigarette smoking.

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

Polymorphisms in cytokine genes responsible for inflammatory and immune responses are associated with risk of hepatocellular carcinoma (HCC) in high-risk Chinese population. Similar data in low-risk populations are lacking. A population-based case-control study of HCC was conducted including 120 HCC patients and 230 matched control subjects of non-Asian residents in Los Angeles County, California. Genetic variants in the interferon gamma (IFNgamma), tumor necrosis factor-alpha (TNFalpha), interleukin-2 (IL-2), IL-4, IL-6, IL-10, IL-12 and IL-18 genes were determined by Taqman assays. The logistic regression method was used to analyze the data. For T helper (Th) 1 genes (IFNgamma, IL-6 and IL-12), relative to the putative high-activity genotypes, individual low-activity genotypes were associated with statistically non-significant increases in HCC risk. The odds ratio (OR) was 1.53 [95% confidence interval (CI) = 0.53-4.39] for three versus zero low-activity genotypes. For Th2 cytokines (IL-4 and IL-10), low- versus high-activity genotypes were associated with statistically non-significant decreases in HCC risk. The OR was 0.64 (95% CI = 0.27-1.55) for two versus zero low-activity genotypes. When the Th1 and Th2 genotypes were examined simultaneously, the highest level of risk was observed in individuals jointly possessing the highest number of low-activity Th1 genotypes and the lowest number of low-activity Th2 genotypes. There was a roughly doubling of risk between these two extreme genetic profiles, which did not reach statistical significance (OR = 1.98, 95% CI = 0.50-7.84, P = 0.08). In contrast to high-risk Chinese, Th1 and Th2 genotypes did not impact in a major way on risk of HCC in USA non-Asians.

Prevention of hepatocellular carcinoma in nonviral-related liver diseases

Although chronic infection with hepatitis B virus and/or hepatitis C virus are the most important risk factors for hepatocellular carcinoma (HCC) worldwide, other causes of cirrhosis can also lead to HCC. Given the high prevalence of alcoholism and the worldwide obesity epidemic, the relevant importance of nonviral liver disease-related HCC is expected to increase in the future. Some evidence supports mechanistic interactions between host or environmental factors and chronic viral hepatitis in the development of HCC. For example, food- and water-borne carcinogens have contributed to unusually high rates of HCC in parts of China and sub-Saharan Africa. With some of these conditions, appropriate public health measures to reduce the population's exposure to known etiologic agents, or early therapeutic intervention for 'at-risk' individuals before development of cirrhosis (e.g. hereditary hemochromatosis) can prevent HCC. Community-based programs to discourage and deal with excessive alcohol intake, to promote tobacco smoking awareness, to avoid exposure to aflatoxin and other food toxins, and measures to reduce the pandemic of obesity and diabetes are vital for effective interruption of the rising tide of HCC from nonviral liver disease.

Prevention of hepatocellular carcinoma complicating chronic hepatitis C

Chronic hepatitis C virus (HCV) infection accounts for most cases of hepatocellular carcinoma (HCC) in Japan and is the second major cause in many other countries. Development of HCC takes a considerable time after onset of HCV infection, between 20-40 years in most cases, and usually develops after cirrhosis is established. Although only a minority of HCV infections reach this stage, the high prevalence of chronic HCV infection in many countries (1-3%) is such that HCC related to HCV infection poses a significant public health issue 20-50 years after the onset of HCV epidemics. Due to advances in testing, and accessibility of clean, disposable medical apparatus including syringes and needles, and particularly screening of donor blood for anti-HCV and by nucleic acid testing, new cases of HCV infection have decreased in most countries, except for continued transmission by injection drug users (IDU). A key difference between HBV and HCV infection is that HCV can be eradicated by effective antiviral treatment. Sustained eradication of HCV reverses hepatic fibrosis, thereby preventing progression to cirrhosis and risk of HCC. Further, it has been well demonstrated that interferon-based antiviral therapy suppresses development of HCC in high-risk patients, particularly when sustained viral response (SVR) is obtained. In summary, the two key approaches to prevent development of HCV-related HCC are primary prevention of HCV infection (adequate programs to screen donor blood, universal precautions to stop medical transmission of blood-borne viruses, curbing transmission by IDU) and potent antiviral therapy of chronic HCV infection.