Alcohol in hepatocellular cancer

Integrated analysis reveals common DNA methylation patterns of alcohol-associated cancers: A pan-cancer analysis

Background: The role of alcohol in carcinogenesis has received increasing attention in recent years. Evidence shows its impacts on various aspects, including epigenetics alteration. The DNA methylation patterns underlying alcohol-associated cancers are not fully understood. Methods: We investigated the aberrant DNA methylation patterns in four alcohol-associated cancers based on the Illumina HumanMethylation450 BeadChip. Pearson coefficient correlations were identified between differential methylated CpG probes and annotated genes. Transcriptional factor motifs were enriched and clustered using MEME Suite, and a regulatory network was constructed. Results: In each cancer, differential methylated probes (DMPs) were identified, and 172 hypermethylated and 21 hypomethylated pan-cancer DMPs (PDMPs) were examined further. Annotated genes significantly regulated by PDMPs were investigated and enriched in transcriptional misregulation in cancers. The CpG island chr19:58220189-58220517 was hypermethylated in all four cancers and silenced in the transcription factor ZNF154. Various biological effects were exerted by 33 hypermethylated and seven hypomethylated transcriptional factor motifs grouped into five clusters. Eleven pan-cancer DMPs were identified to be associated with clinical outcomes in the four alcohol-associated cancers, which might provide a potential point of view for clinical outcome prediction. Conclusion: This study provides an integrated insight into DNA methylation patterns in alcohol-associated cancers and reveals the corresponding features, influences, and potential mechanisms.

Pharmacokinetic changes of tramadol in rats with hepatotoxicity induced by ethanol and acetaminophen in perfused rat liver model

Tramadol is an opioid agonist with activation monoaminergic properties. It can be administered orally, rectally, intravenously, or intramuscularly as a centrally acting analgesic. Liver injury can lead to changes in the metabolism of tramadol. In this study, the rate of tramadol metabolism in rats with damaged liver induced by ethanol and acetaminophen was assessed in a recirculation perfusion system. Acetaminophen is a mild analgesic and antipyretic agent, which can cause centrilobular hepatic necrosis in toxic doses, whereas alcohol causes death due to liver diseases. Alcoholic liver disease (ALD), such as alcoholic fatty liver, alcoholic hepatitis, and alcoholic fibrosis, is the most common liver disease. The aim of this study was to investigate the alteration in tramadol metabolism in different hepatotoxicity conditions in animal models. Male rats were randomly assigned to three groups. The control group received normal saline, group 2 received acetaminophen at the dose of 250 mg/kg/day, and group 3 received ethanol at the beginning dose of 3 g/kg/day, which was slowly increased to 6 g/kg/day. Tramadol was added to the perfusion solution at the concentration of 500 ng/mL. Samples were collected during 180 min, and analyte concentrations were determined by the High-Performance Liquid Chromatography (HPLC) method. The concentration of tramadol and its three main metabolites, O-desmethyltramadol (M1), N-desmethyltramadol (M2), and N,O-didesmethyltramadol (M5), were determined in perfusate samples. Ethanol and acetaminophen significantly affected the pattern of weight gain and liver weights before perfusion and caused a significant increase in enzyme activities. Moreover, histopathologic examination revealed that ethanol and acetaminophen caused liver damage. An increase in the elimination half-life and reduced clearance rate of tramadol were seen in the acetaminophen and ethanol groups, in comparison to the control group. Additionally, significant reductions in the Area Under the Curve (AUC) of metabolites of tramadol (M1, M2, and M5) were observed in the acetaminophen and ethanol groups in the perfused rat liver model. Liver damage caused by ethanol and acetaminophen during 45 days in animals leads to a significant reduction in the level of tramadol metabolites. Therefore, in patients with liver damage caused by ethanol and acetaminophen, caution needs to be considered when prescribing tramadol.

Tomato lycopene prevention of alcoholic fatty liver disease and hepatocellular carcinoma development

Alcoholic liver disease (ALD) is a major cause of morbidity and mortality worldwide. The incidence of hepatocellular carcinoma (HCC) is increasing in the United States, and chronic, excessive alcohol consumption is responsible for 32%–45% of all the liver cancer cases in the United States. Avoidance of chronic or excessive alcohol intake is the best protection against alcohol-related liver injury; however, the social presence and addictive power of alcohol are strong. Induction of the cytochrome P450 2E1 (CYP2E1) enzyme by chronic and excessive alcohol intake is known to play a role in the pathogenesis of ALD. High intake of tomatoes, rich in the carotenoid lycopene, is associated with a decreased risk of chronic disease. The review will overview the prevention of ALD and HCC through dietary tomato rich in lycopene as an effective intervention strategy and the crucial role of CYP2E1 induction as a molecular target. The review also indicates a need for caution among individuals consuming both alcohol and high dose lycopene as a dietary supplement.

Protective effects of Lactococcus chungangensis CAU 28 on alcohol-metabolizing enzyme activity in rats

In this study, we investigated the beneficial effects of Lactococcus chungangensis CAU 28, a bacterial strain of nondairy origin, on alcohol metabolism in rats treated with ethanol, focusing on alcohol elimination and prevention of damage and comparing the effects with those observed for Lactococcus lactis ssp. lactis ATCC 19435. Male Sprague-Dawley rats were orally administered 20% ethanol and 3 substrates (freeze-dried cells, cream cheese, and yogurt) containing Lc. chungangensis CAU 28 or Lc. lactis ssp. lactis ATCC 19435, which were provided 1 h before or 1 h after ethanol ingestion. Blood samples were collected from the tail veins of the rats at 1, 3, 6, 12, and 24 h after ingestion of ethanol, Lc. chungangensis CAU 28 substrate, or Lc. lactis ssp. lactis ATCC 19435 substrate. Alcohol and acetaldehyde concentrations in the Lc. chungangensis CAU 28 substrate-treated rats were significantly reduced in a time-dependent manner compared with those in the Lc. lactis ssp. lactis ATCC 19435 substrate-treated rats. Among the experimental groups, treatment with cream cheese before ingestion of 20% ethanol was found to be the most effective method for reducing both alcohol and acetaldehyde levels in the blood. Alanine aminotransferase and aspartate aminotransferase activities in the Lc. chungangensis CAU 28 substrate-treated rats were significantly lower than those in the positive controls. Moreover, in the Lc. chungangensis CAU 28 cream cheese-treated group, rats showed a reduction of liver enzymes by up to 60%, with good effectiveness observed for both pre- and post-ethanol ingestion. These results suggested that intake of lactic acid bacteria, particularly in Lc. chungangensis CAU 28-supplemented dairy products, may reduce blood alcohol and acetaldehyde concentrations, thereby mitigating acute alcohol-induced hepatotoxicity by altering alcohol-metabolizing enzyme activities.

Ethanol and High Cholesterol Diet Causes Severe Steatohepatitis and Early Liver Fibrosis in Mice

Background and Aim

Because ethanol consumption is commonly associated with a high cholesterol diet, we examined whether combined consumption of ethanol and high cholesterol increases liver injury and fibrosis.

Methods

Male C57BL/6J mice were fed diets containing: 1) 35% of calories from corn oil (CTR), 2) CTR plus 0.5% (w/v) cholesterol (Chol), 3) CTR plus ethanol (27% of calories) (EtOH), or 4) EtOH+Chol for 3 months.

Results

In mice fed Chol or EtOH alone, ALT increased to ~160 U/L, moderate hepatic steatosis occurred, and leukocyte infiltration, necrosis, and apoptosis increased modestly, but no observable fibrosis developed. By contrast in mice fed EtOH+Chol, ALT increased to ~270 U/L, steatosis was more extensive and mostly macrovesicular, and expression of proinflammatory molecules (HMGB-1, TLR4, TNFα, ICAM-1) and leukocyte infiltration increased substantially. Necrosis and apoptosis also increased. Trichrome staining and second harmonic generation microscopy revealed hepatic fibrosis. Fibrosis was mostly sinusoidal and/or perivenular, but in some mice bridging fibrosis occurred. Expression of smooth muscle α-actin and TGF-β1 increased slightly by Chol, moderately by EtOH, and markedly by EtOH+Chol. TGF-β pseudoreceptor BAMBI increased slightly by Chol, remained unchanged by EtOH and decreased by EtOH+Chol. MicroRNA-33a, which enhances TGF-β fibrotic effects, and phospho-Smad2/3, the down-stream signal of TGF-β, also increased more greatly by EtOH+Chol than Chol or EtOH. Metalloproteinase-2 and -9 were decreased only by EtOH+Chol.

Conclusion

High dietary cholesterol and chronic ethanol consumption synergistically increase liver injury, inflammation, and profibrotic responses and suppress antifibrotic responses, leading to severe steatohepatitis and early fibrosis in mice.

Zebrafish as a disease model for studying human hepatocellular carcinoma

Liver cancer is one of the world’s most common cancers and the second leading cause of cancer deaths. Hepatocellular carcinoma (HCC), a primary hepatic cancer, accounts for 90%-95% of liver cancer cases. The pathogenesis of HCC consists of a stepwise process of liver damage that extends over decades, due to hepatitis, fatty liver, fibrosis, and cirrhosis before developing fully into HCC. Multiple risk factors are highly correlated with HCC, including infection with the hepatitis B or C viruses, alcohol abuse, aflatoxin exposure, and metabolic diseases. Over the last decade, genetic alterations, which include the regulation of multiple oncogenes or tumor suppressor genes and the activation of tumorigenesis-related pathways, have also been identified as important factors in HCC. Recently, zebrafish have become an important living vertebrate model organism, especially for translational medical research. In studies focusing on the biology of cancer, carcinogen induced tumors in zebrafish were found to have many similarities to human tumors. Several zebrafish models have therefore been developed to provide insight into the pathogenesis of liver cancer and the related drug discovery and toxicology, and to enable the evaluation of novel small-molecule inhibitors. This review will focus on illustrative examples involving the application of zebrafish models to the study of human liver disease and HCC, through transgenesis, genome editing technology, xenografts, drug discovery, and drug-induced toxic liver injury.

Incidence, risk factors and outcome of de novo tumors in liver transplant recipients focusing on alcoholic cirrhosis

Orthotopic liver transplantation (OLT) is an established life-saving procedure for alcoholic cirrhotic (AC) patients, but the incidence of de novo tumors ranges between 2.6% and 15.7% and is significantly increased in comparison with patients who undergo OLT for other etiologies. Tobacco, a known carcinogen, has been reported to be between 52% and 83.3% in AC patients before OLT. Other risk factors that contribute to the development of malignancies are dose-dependent immunosuppression, advanced age, viral infections, sun exposure, and premalignant lesions (inflammatory bowel disease, Barrett’s esophagus). A significantly more frequent incidence of upper aerodigestive (UAD) tract, lung, skin, and kidney-bladder tumors has been found in OLT recipients for AC in comparison with other etiologies. Liver transplant recipients who develop de novo non-skin tumors have a decreased long-term survival rate compared with controls. This significantly lower survival rate is more evident in AC recipients who develop UAD tract or lung tumors after OLT mainly because the diagnosis is usually performed at an advanced stage. All transplant candidates, especially AC patients, should be encouraged to cease smoking and alcohol consumption in the pre- and post-OLT periods, use skin protection, avoid sun exposure and over-immunosuppression, and have a yearly otopharyngolaryngeal exploration and chest computed tomography scan in order to prevent or reduce the incidence of de novo malignancies. Although still under investigation, substitution of calcineurin inhibitors for sirolimus or everolimus may reduce the incidence of de novo tumors after OLT.

[Occult hepatitis B virus infection and hepatocellular carcinoma]

Many studies have suggested that occult HBV infection has a substantial clinical relevance to hepatocellular carcinoma (HCC). Occult HBV infection is an important risk factor for the development of cirrhosis and HCC in patients without HBsAg. As a matter of fact, occult HBV infection is one of the most common causes of crytogenic HCC in endemic areas of HBV. However, there still are controversial issues about the association between occult HBV infection and HCC according to the underlying liver disease. In alcoholic cirrhosis, occult HBV infection may exert synergistic effect on the development of HCC. However, there is insufficient evidence to relate occult HBV infection to hepatocarcinogenesis in non-alcoholic fatty liver disease. In cryptogenic HCC, occult HBV infection may play a direct role in the development of HCC. In order to elucidate the assocciation between occult HBV infection and HCC, underlying liver disease must be specified and larger number of cases must be included in future studies.

Maotai ameliorates diethylnitrosamine-initiated hepatocellular carcinoma formation in mice

Consumption of alcohol is closely related to liver disease, such as hepatic fibrosis or even hepatocellular carcinoma (HCC). However, epidemiological and experimental studies indicated that consumption of Maotai, one of the famous liquors in China, exhibits no significant correlation with hepatic fibrosis or cirrhosis as other beverage sources do. This study detected the relationship of Maotai consumption and HCC development in a diethylnitrosamine (DEN)-initiated HCC animal model. DEN was given to mice at a dose of 100 mg/kg, ip, and 50 mg/kg, ip in the following week. Mice were simultaneously given Maotai or an equal amount of ethanol (53%, 5 ml/kg/day, 5days/week for up to 35weeks). At 3-week and 35- week of the experiment, serum and livers were collected for biochemical and histopathological examination of liver injury and incidence of HCC. Real-time RT-PCR, immunohistochemistry and Western blotting were used to examine the expression of metallothionein-1/2 (MT-1/2), NF-E2-related factor 2 (Nrf2), glutamate-cysteine ligase catalytic subunit (GCLC) and modified subunit (GCLM). We identified tissue damage and dysfunction of liver in ethanol + DEN-treated mice, whereas the extent of injury was reduced in Maotai+ DEN –treated mice. Significant Glypican-3(GPC3) expression and precancerous injury or HCC were seen in approximately 50% of mice with ethanol+ DEN, but barely be seen in Maotai + DEN-treated mice. A higher expression of MT-1/2, Nrf2 and GCLC could be seen in Maotai + DEN-treated mice. Thus, Maotai liquor ameliorates the formation of DEN-induced HCC in mice, and the protection mechanism is possibly related with the activation of anti-oxidation factors, such as MTs, Nrf2 and GCLC.

Evaluation of hepatic fibrosis using intravoxel incoherent motion in diffusion-weighted liver MRI

OBJECTIVES

To determine whether intravoxel incoherent motion (IVIM)-diffusion-weighted image (DWI)-derived parameters showed better diagnostic performance than the apparent diffusion coefficient (ADC(total)) for the evaluation of hepatic fibrosis (HF).

METHODS

This retrospective study was approved by institutional review board, and informed consent was waived. Fifty-five patients with chronic liver disease who had undergone IVIM-DWI using 8 b-values at 3 T were included. True diffusion coefficient (Dt), pseudo-diffusion coefficient (Dp), perfusion fraction (f), and ADC(total) were calculated. Receiver operating characteristic analysis was performed for all parameters for the HF staging.

RESULTS

All parameters showed a significant correlation with the HF stages (-0.31 to -0.72, P < 0.05). All parameters were significantly higher in F0 to F1 than in F4 (P < 0.05). The Dp showed better performance than the ADC(total) in differentiating significant HF (≥F2) from F0 to F1.

CONCLUSIONS

The IVIM-derived parameters and ADC(total) showed significant correlation with HF. The D p showed better diagnostic performance for differentiating significant HF than did ADC(total).

Alcohol interacts with genetic alteration of the Hippo tumor suppressor pathway to modulate tissue growth in Drosophila

Alcohol-mediated cancers represent more than 3.5% of cancer-related deaths, yet how alcohol promotes cancer is a major open question. Using Drosophila, we identified novel interactions between dietary ethanol and loss of tumor suppressor components of the Hippo Pathway. The Hippo Pathway suppresses tumors in flies and mammals by inactivating transcriptional co-activator Yorkie, and the spectrum of cancers associated with impaired Hippo signaling overlaps strikingly with those associated with alcohol. Therefore, our findings may implicate loss of Hippo Pathway tumor suppression in alcohol-mediated cancers. Ethanol enhanced overgrowth from loss of the expanded, hippo, or warts tumor suppressors but, surprisingly, not from over-expressing the yorkie oncogene. We propose that in parallel to Yorkie-dependent overgrowth, impairing Hippo signaling in the presence of alcohol may promote overgrowth via additional alcohol-relevant targets. We also identified interactions between alcohol and Hippo Pathway over-activation. We propose that exceeding certain thresholds of alcohol exposure activates Hippo signaling to maintain proper growth control and prevent alcohol-mediated mis-patterning and tissue overgrowth.

Influence of alcohol consumption on oxidative stress and antioxidant status in cancer patients--case-control study from Western Nepal

AIM

The present study assess the effect of consumption of alcohol on oxidative stress and antioxidant status in patients suffering from different types of cancer.

METHODS

This hospital based case control study conducted in the Western part of Nepal covered a total of 93 cancer patients with or without alcohol intake and smoking habits, along with 94 age, sex and habit-matched individuals serving as controls. Plasma thiobarbituric acid reacting substances (TBARS), total antioxidant activity (TAA), vitamin C, α-tocopherol and erythrocyte reduced glutathione (GSH) were estimated and compared.

RESULTS

The TBARS level was found to be significantly higher (p≤0.001) in all types of cancer patients when compared to controls, being aggravated in alcoholics with a smoking habit. No statistical significance (p≥0.05) was observed in the level of vitamin C and α-tocopherol. GSH and TAA level were significantly decreased (p≤0.001) in all the groups except those who consumed both branded as well as homemade alcohol and non-alcoholics without smoking habit.

CONCLUSION

Alcohol, irrespective of its commercial brand, increases oxidative stress in all types of cancer patients. This is even higher when alcohol intake is combined with a smoking habit. Decreased TAA and GSH are major risk factors for cancer development.

Heavy alcohol consumption increases the incidence of hepatocellular carcinoma in hepatitis B virus-related cirrhosis

BACKGROUND & AIMS

Taiwan has a high prevalence of hepatitis B viral (HBV) infection and hepatocellular carcinoma (HCC) with increasing consumption of alcohol. We investigated the impact of heavy alcohol consumption and HBV infection on HCC in cirrhotic patients.

METHODS

966 cirrhotic patients (132 with HBV infection and alcoholism, 632 with HBV infection, and 202 patients with alcoholism) were enrolled between 2000 and 2009 and followed until 2011. The primary end point was newly developed HCC.

RESULTS

Within the three patient groups (cirrhotic patients with HBV infection and alcoholism, HBV infection alone, and alcoholism alone) 38 (28.8%), 100 (15.8%), and 21 (10.4%) showed newly developed HCC, respectively. The 10-year cumulative (52.8% vs. 39.8% vs. 25.6%, p <0.001) and annual incidences (9.9%, 4.1%, and 2.1%) of HCC were significantly higher in cirrhotic patients with HBV infection and alcoholism than those in patients with HBV infection or alcoholism alone. For patients with HBV infection and alcoholism, baseline serum HBV DNA (OR=16.8, p=0.025), antiviral nucleos(t)ides analogues (NUCs) therapy (OR=0.01, p=0.035), and serum α-fetoprotein (OR=1.18, p=0.045) were risk predictors of HCC by multivariate logistic regression models. The cumulative incidence of HCC was higher in patients with higher baseline serum HBV DNA. Antiviral NUCs therapy reduced the incidence of HCC.

CONCLUSIONS

Heavy alcohol consumption significantly increased the risk of HCC in HBV-related cirrhotic patients. Elevated baseline serum HBV DNA was a strong risk predictor of HCC and antiviral NUCs therapy reduced the incidence of HCC in cirrhotic patients with HBV infection and alcoholism.

Alcohol consumption and digestive tract cancer

PURPOSE OF REVIEW

The data indicating that alcohol is an important factor increasing the risk to develop gastrointestinal cancer are consolidating. The purpose of this review is to summarize current evidence.

RECENT FINDINGS

Acetaldehyde is the first metabolite of ethanol metabolism and has direct carcinogenic and mutagenic effects by modifying DNA via generation of DNA adducts. Oxidative stress has a prominent role in triggering chronic inflammation and carcinogenesis through formation of reactive oxygen species. Recently published large prospective cohort studies with sufficient statistical power and meta-analyses could refine the knowledge regarding the impact of alcohol on gastrointestinal cancer. Functional genetic variants of alcohol-metabolizing enzymes proved to be associated with increased risk for esophageal and gastric cancer.The highest risk increase for malignancy was observed in the upper aerodigestive tract (oral cavity, pharynx, larynx) and esophagus (squamous cell carcinoma), weaker correlations were established regarding gastric, pancreatic, and colorectal neoplasias.

SUMMARY

Alcohol overconsumption is a serious avoidable risk factor for the development of gastrointestinal tract cancer, both alone but even more in combination with other risk factors such as tobacco and obesity.

Anti-hepatitis B core positivity as a risk factor for hepatocellular carcinoma in alcoholic cirrhosis: a case-control study

Hepatocellular carcinoma (HCC) is occasionally developed in patients with alcoholic cirrhosis. Old age, male gender, lifetime quantity of alcohol, and presence of hepatitis C virus (HCV) infection are risk factors for HCC in alcoholic cirrhosis. In this study, we investigated whether anti-hepatitis B core (HBc) positivity or occult hepatitis B virus (HBV) infection is a risk factor for HCC in patients with alcoholic cirrhosis. Between January 2006 and August 2008, a total of 72 cirrhotic male patients with an initial diagnosis of HCC, hospitalized in three major hospitals in the Incheon area, were enrolled as cases. Another 72 cirrhotic male patients without HCC, who matched the cases by age (±3 years), were enrolled as controls. All cases and controls were negative for hepatitis B surface antigen and anti-HCV, but had history of chronic alcohol intake over 80 g per day. The clinical characteristics including presence of anti-HBc or serum HBV DNA (identified by nested polymerase chain reaction) were investigated. The mean age of both the cases and controls was 62 ± 10 years. The basal laboratory data, Child-Pugh scores, total lifetime alcohol intake (1459 ± 1364 versus 1641 ± 1045 kg), and detection rates of serum HBV DNA [31.7% (20/63) versus 29.9% (20/67)] of the cases and controls were not significantly different. However, the anti-HBc positivity rate was higher among the cases [86.1% (62/72)] than in the controls [66.7% (48/72); p=0.005] and was the only significant risk factor for HCC (odds ratio; 3.1, 95% confidence interval; 1.354-7.098, p=0.007). Anti-HBc positivity was identified as a risk factor for the development of HCC in patients with alcoholic cirrhosis.

Genetic variation in the NBS1 gene is associated with hepatic cancer risk in a Chinese population

NBS1 plays important roles in maintaining genomic stability as a key DNA repair protein in the homologous recombination repair pathway and as a signal modifier in the intra-S phase checkpoint. We hypothesized that polymorphisms of NBS1 are associated with hepatic cancer (HCC) risk. The NBS1 rs1805794 C/G polymorphism has been frequently studied in some cancers with discordant results, but its association with HCC has not been investigated. Moreover, studies of the 3'UTR variant rs2735383 have not touched upon HCC. This study examined the contribution of these two polymorphisms to the risk of developing HCC in a Chinese population. NBS1 genotypes were determined in 865 HCC patients and 900 controls and the associations with risk of HCC were estimated by logistic regression. Compared with the rs1805794 GG genotype, the GC genotype had a significantly increased risk of HCC (adjusted odds ratios [OR]=1.41; 95% confidence interval [CI]=1.11-1.80), the CC carriers had a further increased risk of HCC (OR=2.27; 95% CI=1.68-3.14), and there was a trend for an allele dose effect on risk of HCC (p<0.001). Also, we found that the risk effect of rs1805794 CC+CG was more pronounced in HCC patients that drank (OR=2.28, 95% CI=1.55-3.29 for drinkers; OR=1.31, 95% CI=1.00-1.77 for nondrinkers). However, there was no significant difference in genotype frequencies of rs2735383 G/C site between cases and controls. These findings suggest that rs1805794 C/G polymorphism in NBS1 may be a genetic modifier for developing HCC.

Heavy alcohol use and premature death from hepatocellular carcinoma in the United States, 1999-2006

OBJECTIVE

The incidence rate of hepatocellular carcinoma has been rising in the United States during the last 2 decades. Heavy alcohol use has been widely recognized as one of the major etiological factors of hepatocellular carcinoma. This study sought to assess the extent to which heavy alcohol use contributed to premature death from hepatocellular carcinoma on a population scale in the United States.

METHOD

We analyzed the Multiple Cause of Death public-use data sets. Using codes from the International Classification of Diseases, 10th Revision, hepatocellular carcinoma death was defined based on the underlying cause of death, and heavy alcohol use was indicated by the presence of any alcohol-induced medical conditions among the contributing causes of death. During 1999-2006 in the United States, 51,400 hepatocellular carcinoma deaths were identified from 17,727,245 natural deaths of persons age 25 or older. We conducted Poisson regression, life table, and multiple linear regression analyses to compare prevalence ratios, cumulative probabilities, and mean ages of death, respectively, from hepatocellular carcinoma by heavy alcohol use status across sex and race/ethnicity.

RESULTS

Heavy alcohol use decedents had higher prevalence ratios of dying from hepatocellular carcinoma than from non-chronic liver diseases compared with those decedents without heavy alcohol use. Heavy alcohol use was associated with decreased mean ages and increased cumulative probabilities of death among hepatocellular carcinoma decedents across racial/ethnic groups in both sexes. This association was stronger among women than men and stronger among non-Hispanic Whites than non-Hispanic Blacks.

CONCLUSIONS

This study provides mortality-based empirical evidence to further establish heavy alcohol consumption as one of the key risk factors contributing to premature deaths from hepatocellular carcinoma in the United States, and its effect appears more prominent among women and non-Hispanic Whites.

Effect of alcohol on the development of hepatocellular carcinoma in patients with hepatitis B virus-related cirrhosis: a cross-sectional case-control study

Background/Aims

Whether alcohol intake increases the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B virus (HBV) infection remains controversial. The aim of this study was to determine the effect of alcohol intake on the development of HCC.

Methods

Between January 2006 and August 2008, 146 patients with an initial diagnosis of HCC who were hospitalized in 3 major hospitals in the Incheon area were enrolled as cases. Another 146 cirrhotic patients, who matched the cases by age and sex, were enrolled as controls. All cases and controls were HBsAg positive, and had a history of lifetime alcohol intake.

Results

The cases and controls were aged 53±8 and 53±9 years (mean±SD), respectively, with each group comprising 118 males and 28 females. The basal laboratory data, distribution of Child-Pugh class, HBeAg positivity (31.5% vs. 37.7%), HBV DNA level (5.74±2.35 vs. 5.98±2.29 log₁₀ copies/mL), and proportion with a lifetime alcohol intake of more than 292 kg (30.8% vs. 34.9%) did not differ between cases and controls. The cumulative alcohol intake and the proportion of heavy drinkers did not differ between the two groups in male patients.

Conclusions

Alcohol intake might not increase the risk of HCC in patients with HBV infection.

Diffusion tensor imaging of liver fibrosis in an experimental model

PURPOSE

To characterize changes in diffusion properties of liver using diffusion tensor imaging (DTI) in an experimental model of liver fibrosis.

MATERIALS AND METHODS

Liver fibrosis was induced in Sprague-Dawley rats (n = 12) by repetitive dosing of carbon tetrachloride (CCl(4)). The animals were examined with a respiratory-gated single-shot spin-echo echo-planar DTI protocol at 7 T before, 2 weeks after, and 4 weeks after CCl(4) insult. Apparent diffusion coefficient (ADC), directional diffusivities (ADC(//) and ADC(⊥)), and fractional anisotropy (FA) were measured. Liver histology was performed with hematoxylin-eosin staining and Masson's trichrome staining.

RESULTS

Significant decrease (P < 0.01) in ADC was found at 2 weeks (0.86 ± 0.09 × 10(-3) mm(2)/s) and 4 weeks (0.74 ± 0.09 × 10(-3) mm(2)/s) following CCl(4) insult, as compared with that before insult (0.97 ± 0.08 × 10(-3) mm(2)/s). Meanwhile, FA at 2 weeks (0.18 ± 0.03) after CCl(4) insult was significantly lower (P < 0.01) than that before insult (0.26 ± 0.05), and subsequently normalized at 4 weeks (0.26 ± 0.07) after the insult. Histology showed collagen deposition, presence of intracellular fat vacuoles, and cell necrosis/apoptosis in livers with CCl(4) insult.

CONCLUSION

DTI detected the progressive changes in water diffusivities and diffusion anisotropy of liver tissue in this liver fibrosis model. ADC and FA are potentially valuable in detecting liver fibrosis at early stages and monitoring its progression. Future human studies are warranted to further verify the applicability of DTI in characterizing liver fibrosis and to determine its role in clinical settings.

Acetaldehyde adducts in alcoholic liver disease

Chronic alcohol abuse causes liver disease that progresses from simple steatosis through stages of steatohepatitis, fibrosis, cirrhosis, and eventually hepatic failure. In addition, chronic alcoholic liver disease (ALD), with or without cirrhosis, increases risk for hepatocellular carcinoma (HCC). Acetaldehyde, a major toxic metabolite, is one of the principal culprits mediating fibrogenic and mutagenic effects of alcohol in the liver. Mechanistically, acetaldehyde promotes adduct formation, leading to functional impairments of key proteins, including enzymes, as well as DNA damage, which promotes mutagenesis. Why certain individuals who heavily abuse alcohol, develop HCC (7.2-15%) versus cirrhosis (15-20%) is not known, but genetics and co-existing viral infection are considered pathogenic factors. Moreover, adverse effects of acetaldehyde on the cardiovascular system and hematologic systems leading to ischemia, heart failure, and coagulation disorders, can exacerbate hepatic injury and increase risk for liver failure. Herein, we review the role of acetaldehyde adducts in the pathogenesis of chronic ALD and HCC.

Estimation of cancer incidence and mortality attributable to alcohol drinking in China

BACKGROUND

Cancer constitutes a serious burden of disease worldwide and has become the second leading cause of death in China. Alcohol consumption is causally associated with the increased risk of certain cancers. Due to the current lack of data and the imperative need to guide policymakers on issues of cancer prevention and control, we aim to estimate the role of alcohol on the cancer burden in China in 2005.

METHODS

We calculated the proportion of cancers attributable to alcohol use to estimate the burden of alcohol-related cancer. The population attributable fraction was calculated based on the assumption of no alcohol drinking. Data on alcohol drinking prevalence were from two large-scale national surveys of representative samples of the Chinese population. Data on relative risk were obtained from meta-analyses and large-scale studies.

RESULTS

We found that a total of 78,881 cancer deaths were attributable to alcohol drinking in China in 2005, representing 4.40% of all cancers (6.69% in men, 0.42% in women). The corresponding figure for cancer incidence was 93,596 cases (3.63% of all cancer cases). Liver cancer was the main alcohol-related cancer, contributing more than 60% of alcohol-related cancers.

CONCLUSIONS

Particular attention needs to be paid to the harm of alcohol as well as its potential benefits when making public health recommendations on alcohol drinking.

Independent and additive interactive effects among tumor necrosis factor-alpha polymorphisms, substance use habits, and chronic hepatitis B and hepatitis C virus infection on risk for hepatocellular carcinoma

We conducted a case-control study to assess the roles of tumor necrosis factor (TNF)-alpha polymorphisms, substance use habits, and chronic hepatitis B virus (HBV)/hepatitis C virus (HCV) infection on the risk for hepatocellular carcinoma (HCC). We enrolled 200 pairs of sex- and age-matched patients with HCC and unrelated healthy controls. TNF-alpha polymorphisms were detected with polymerase chain reaction and direct sequencing. Serum hepatitis B surface antigen (HBsAg) and antibodies to HCV (anti-HCV) were detected. We used a structured questionnaire to obtain information about substance use habits.Multivariate analysis indicated that TNF308.2 allele (odds ratio [OR], 3.23; p = 0.011), habitual betel quid chewing (OR, 3.70; p = 0.011), HBsAg (OR, 23.62; p = 0.0001), and anti-HCV (OR, 38.73; p = 0.0001) were independent risk factors for HCC. Having at least 2 substance use habits was associated with risk for HCC. The more substance use habits, the higher the OR for HCC (p(for trend) = 0.0001). There were additive interactions among TNF308.2 allele, substance use habits, and chronic HBV/HCV infection. Multivariate analysis indicated that TNF308.2 allele (p = 0.001), cigarette smoking (p = 0.0001), and alcohol drinking (p = 0.0001) were independent risk factors for habitual betel quid chewing. Moreover, patients harboring the TNF308.2 allele and/or those with habits of substance use had low serum albumin concentration and platelet count (each p = 0.0001). In conclusion, there are independent and additive interactive effects among the TNF308.2 allele, substance use habits, and chronic HBV/HCV infection on the risk for HCC. Substance use habits or carrying the TNF308.2 allele correlates with disease severity and hepatic fibrosis, which may contribute to higher risks for HCC.

In vivo measurement of ethanol metabolism in the rat liver using magnetic resonance spectroscopy of hyperpolarized [1-13C]pyruvate

[1-(13)C]pyruvate is a readily polarizable substrate that has been the subject of numerous magnetic resonance spectroscopy (MRS) studies of in vivo metabolism. In this work (13)C-MRS of hyperpolarized [1-(13)C]pyruvate was used to interrogate a metabolic pathway involved in neither aerobic nor anaerobic metabolism. In particular, ethanol consumption leads to altered liver metabolism, which when excessive is associated with adverse medical conditions including fatty liver disease, hepatitis, cirrhosis, and cancer. Here we present a method for noninvasively monitoring this important process in vivo. Following the bolus injection of hyperpolarized [1-(13)C]pyruvate, we demonstrate a significantly increased rat liver lactate production rate with the coadministration of ethanol (P = 0.0016 unpaired t-test). The affect is attributable to increased liver nicotinamide adenine dinucleotide (NADH) associated with ethanol metabolism in combination with NADH's role as a coenzyme in pyruvate-to-lactate conversion. Beyond studies of liver metabolism, this novel in vivo assay of changes in NADH levels makes hyperpolarized [1-(13)C]pyruvate a potentially viable substrate for studying the multiple in vivo metabolic pathways that use NADH (or NAD(+)) as a coenzyme, thus broadening the range of applications that have been discussed in the literature to date.

[The significance of anti-HBc and occult hepatitis B virus infection in the occurrence of hepatocellular carcinoma in patients with HBsAg and anti-HCV negative alcoholic cirrhosis]

BACKGROUND/AIMS

Alcohol and the hepatitis B virus (HBV) exert synergistic effects in hepatocelluar carcinogenesis. We aimed to elucidate the clinical significance of the antibody to hepatitis B core antigen (anti-HBc) and occult HBV infection on the development of hepatocellular carcinoma (HCC) in patients with alcoholic liver cirrhosis (LC).

METHODS

Patients with alcoholic LC alone (n=193) or combined with HCC (n=36), who did not have HBsAg or antibody to hepatitis C virus were enrolled. Clinical data and laboratory data including anti-HBc were investigated at enrollment. The polymerase chain reaction was applied to HBV DNA using sera of patients with HCC or LC after age and sex matching.

RESULTS

Patients with HCC were older (60+/-11 years vs. 53+/-10 years, mean+/-SD, P<0.001), more likely to be male (100% vs. 89%, P=0.03), and had a higher positive rate of anti-HBc (91.2% vs. 77.3%, P=0.067), and a higher alcohol intake (739+/-448 kg vs. 603+/-409 kg, P=0.076) than those with LC. Age was the only significant risk factor for HCC revealed by multiple logistic regression analysis (odds ratio, 1.056; P=0.003). The positive rate of anti-HBc and alcohol intake did not differ in age- and sex-matched subjects between the LC (n=32) and HCC (n=31) groups. However, the detection rate of serum HBV DNA was higher in the HCC group (48.4%) than in the LC group (0%, P<0.001).

CONCLUSIONS

Anti-HBc positivity is not a risk factor for HCC. However, occult HBV infection may be a risk factor for HCC in patients with alcoholic LC.

[Risks factors for pediatric malignant liver tumors]

OBJECTIVE

Pediatric Hepatic Malignancies (PHMs) are the result of the interaction between constitutional and environmental risk factors (RFs). We review the evidence on the main RFs associated to PHMs.

METHOD

Systematic review of the literature published in the last 25 years on Medline, Embase, Cancerlit, Lilacs and SciElo using the following key words: "etiology/risk factor/epidemiology" and "malignant liver tumors/hepatic cancer" or "hepatoblastoma/hepatocarcionoma".

RESULTS

PHMs account for 1 % of all pediatric malignancies. The main types, hepatoblastoma (HB) and hepatocarcionma (HCC) make up 98-99 % of PHM. The main constitutional RFs are: a) Beckwith-Wiedemann (BW) syndrome; b) isolated hemihyperplasia syndrome (IHS); c) adenomatous polyps of the colon; d) hemochromatosis; e) Hereditary Tyrosinemia Type 1; f) a -1-antitrypsin deficiency; g) porphyrias; h) cirrhosis; i) nonalcoholic steatosis; and j) primary sclerosing cholangitis. The main environmental RFs are: a) hepatitis B virus (HBV) and C virus (HCV); b) B1 aflatoxin (B1AF); c) ionizing radiation; d) alcohol; e) hormonal treatments; f) occupational exposure to pesticides, solvents, vinyl chloride and metals; g) smoking; h) arsenic; i) prematury and very low birth weight; and j) trematodes.

CONCLUSIONS

The clinical, analytical and ultrasound screening facilitate the early diagnosis of HB in the previously mentioned genetic syndromes, particularly BW and IHS during the first years of life. HBV universal vaccination of newborns provides the biggest opportunity to prevent a substantial proportion of PHMs. Also systematic monitoring of HBV and HCV in blood, hemoderivates, donated organs and drug addicts, are very useful. Other effective measures are: the reduction/elimination of B(1)AF in food, zero alcohol intake during childhood and adolescence as well decreasing prenatal exposure to the tobacco, solvents, pesticides, vinyl chloride, metals, ionizing radiation and hormonal treatments.

Orbital metastasis of hepatocellular carcinoma

We report a 74-year-old woman who presented with an orbital apex syndrome and pulsatile proptosis. CT showed a right orbital mass that destroyed the orbital sphenoid bone and extended intracranially. Biopsy revealed metastatic hepatocellular carcinoma (HCC), and subsequent investigations demonstrated a high level of serum-fetoprotein and a huge liver mass. The patient died shortly after the biopsy. Rarely reported in the English literature, metastatic HCC is common in Asia, perhaps because of a racial predisposition together with a relatively high prevalence of alcoholic cirrhosis, chronic hepatitis B and C, and exposure to aflatoxins.

Chronic ethanol intake promotes double gluthatione S-transferase/transforming growth factor-alpha-positive hepatocellular lesions in male Wistar rats

The chronic ethanol intake influence on the gluthatione S-transferase (GST-P) and transforming growth factor alpha (TGF-alpha) expression in remodeling/persistent preneoplastic lesions (PNLs) was evaluated in the resistant hepatocyte model. Male Wistar rats were allocated into five groups: G1, non-treated, fed water and chow ad libitum; G2, non-treated and pair-fed chow (restricted to match that of G3 group) and a maltodextrin (MD) solution in tap water (matched ethanol-derived calories); G3, fed 5% ethanol in drinking water and chow ad libitum; G4, diethylnitrosamine (DEN, 200 mg/kg, body weight) plus 200 parts per million of 2-acetylaminofluorene (2-AAF) for 3 weeks and pair-fed chow (restricted to match that of G5 group) and an MD solution in tap water (matched ethanol-derived calories); G5, DEN/2-AAF treatment, fed ethanol 5% and chow ad libitum. All animals were subjected to 70% partial hepatectomy at week 3 and sacrificed at weeks 12 or 22, respectively. Liver samples were collected for histological analysis or immunohistochemical expression of GST-P, TGF-alpha and proliferating cell nuclear antigen or zymography for matrix metalloproteinases-2 and -9. At the end of ethanol treatment, there was a significant increase in the percentage of liver area occupied by persistent GST-P-positive PNLs, the number of TGF-alpha-positive PNLs and the development of liver tumors in ethanol-fed and DEN/2-AAF-treated groups (G5 versus G4, P < 0.001). In addition, ethanol feeding led to a significant increase in cell proliferation mainly in remodeling and persistent PNLs with immunoreactivity for TGF-alpha at week 22 (P < 0.001). Gelatinase activities were not altered by ethanol treatment. The results demonstrated that ethanol enhances the selective growth of PNL with double expression of TGF-alpha and GST-P markers.

Bone marrow cell transplant does not prevent or reverse murine liver cirrhosis

We tested the effect of bone marrow cell (BMC) transplantation in either preventing or reversing cirrhosis on an experimental model of chronic liver disease. Female Wistar rats were fed a liquid alcohol diet and received intraperitoneal injections of carbon tetrachloride (CCl4) over 15 weeks. Ten animals (cell-treated group) received five injections of BMCs during the cirrhosis induction protocol (on the 4th, 6th, 8th, 10th, and 12th weeks) and four animals received the cells after liver injury was established through tail vein. Nine animals (nontreated group) were submitted to the previously described protocols; however, they received vehicle injections. Analyses were performed to verify whether the infusion of cells was effective in preventing the development of cirrhosis in our model of induction, and if the cells could reverse cirrhosis once it was established. Hepatic architecture and fibrotic septa were analyzed in liver slices stained with hematoxilin & eosin and Sirius red, respectively. Fibrosis quantification was measured by Sirius red histomorphometry. Indirect immunofluorescence was performed to detect the amount of tissue transglutaminase 2. Blood analyses were performed to assess liver injury and function by the assessment of alanine aminotransferase and albumin. Ultrasound was performed to analyze the portal vein caliber and presence of ascitis. Cirrhosis features (regenerative nodules and fibrous septa) were observed in histopathology after 15 weeks of continuous hepatic injury in nontreated and cell-treated groups. Collagen content, immunofluorescence analysis, and biochemical and ultrasound parameters were similar in nontreated and cell-treated groups; however, both groups showed significant differences compared to a normal control group. Cell infusions with bone marrow-derived cells seem to be ineffective in improving morphofunctional parameters of the liver when applied to chronic cases either during or after establishment of the hepatic lesion.

Evaluation of the effect of ethanol's toxic metabolite acetaldehyde on the gastrointestinal oligopeptide transporter, PEPT1: in vitro and in vivo studies

BACKGROUND

The effects of alcohol consumption and its subsequent metabolism on drug transport, absorption and pharmacokinetics are poorly understood. This study examines the effects of the ethanol metabolite, acetaldehyde, on the clinically relevant drug transporter, PEPT1. The metabolism of ethanol and the following acetaldehyde formation is thought to modulate the uptake capacity of PEPT1 within the gastrointestinal tract for a variety of clinically important peptidomimetic drug compounds.

METHODS

Glycylsarcosine ([(3)H]-GlySar), a nonhydrolysable PEPT1 specific substrate was used in our studies. In vitro uptake studies were performed in the Caco-2 and Chinese hamster ovary (CHO)-hPEPT1 cell models, measuring cellular uptake of labeled compound against increasing levels of unlabeled compound in the presence of acetaldehyde. In vivo absorption of [(3)H]-GlySar was measured in male Sprague-Dawley rats that were treated with oral dose of ethanol/disulfiram (5 g/kg / 100 mg/kg) for 6 days. These results were compared to control rats treated with saline, ethanol alone or disulfiram alone.

RESULTS

In vitro uptake of [(3)H]-GlySar in CHO-hPEPT1 cells treated with 1 mM acetaldehyde was significantly decreased (p < 0.05) as compared to untreated controls. The uptake of [(3)H]-GlySar in Caco-2 cell monolayers treated with 1 mM acetaldehyde was also significantly decreased as compared to the untreated control cells. In vivo absorption of [(3)H]-GlySar in ethanol treated rats, as measured by AUC(0-12 hours) were decreased by approximately 50% versus the control rat group.

CONCLUSION

The effects of acetaldehyde due to consumption of ethanol on the uptake and bioavailability of therapeutic drug compounds transported by the PEPT1 oligopeptide transporter have not been documented. In the present studies, we demonstrate that acetaldehyde significantly modulates PEPT1 function and, thereby, affects drug bioavailability. To our best knowledge, this is the first report on the effects of an ethanol metabolite on substrate absorption in the gastrointestinal tract, rather than interactions in the liver, which is an under-represented area of research in alcohol pathophysiology.

Alcoholic liver disease

Alcohol excess is associated with a spectrum of disease ranging from simple steatosis through steatohepatitis to cirrhosis and, in some, hepatocellular carcinoma. Alcoholic steatohepatitis itself has a variable histological picture, but a constant feature is the presence of ballooning degeneration of hepatocytes. Recent studies have emphasized the importance of apoptosis as a mechanism of cell death in this condition. It is accompanied by varying degrees of perivenular, centrilobular, and pericellular fibrosis. When severe and associated with perivenular liver cell necrosis (central sclerosing hyaline necrosis), there may be precirrhotic portal hypertension. The pattern of fibrosis may initially be diffuse with little nodule formation, but in time there is frequently the development of a micronodular cirrhosis. In approximately 15% of patients with established cirrhosis, hepatocellular carcinoma develops; several precursor lesions are now recognized which can be detected histologically. Several authors have drawn attention to additional components of the spectrum of alcoholic liver disease, including vascular changes, portal tract inflammation and fibrosis, ductular reaction, and iron overload. The morphology of alcoholic liver disease can be significantly affected by abstinence; furthermore, the clinical and morphological phenotype can be significantly influenced by the presence of comorbid conditions such as nonalcoholic fatty liver disease or viral hepatitis. Biopsy appearances can provide important prognostic information in alcoholic liver disease, and this review incorporates a proposed grading and staging schema for assessment of histological severity.

DNA methylation and hepatocellular carcinoma

The epigenetic makeup of organisms forms a link between the genetic information (DNA sequence) and the gene expression (and therefore phenotype). It dictates the memory for the gene expression pattern that, in turn, specifies cell identity. DNA methylation is the most studied epigenetic mechanism, aberration of which prevails in cancer, resulting in an altered pattern of gene expression and, therefore, cancerous features, including genetic abnormalities: mutations and genome instability. Altered methylation in cancer occurs in two directions. A marked reduction in the overall level of DNA methylation has been linked to the activation of transcription/transposition and the overexpression of protooncogenes. In parallel, there is a common occurrence of a hypermethylated status of the promoter cytosine (CpG) island in genes involved in the negative control of cell growth and in the maintenance of genomic stability; therefore causing transcription silencing. It is thus necessary and important to establish a comprehensive profile of DNA methylation changes in the promoter CpG island in many genes, both for better understanding of the underlying mechanisms and for diagnostic purposes in cancer clinics. Hepatocellular carcinoma is one of the most threatening malignancies in East Asia and Africa. In this short review, I briefly outline our current understanding of DNA methylation in cancer in general, emphasizing its recent progress in hepatocellular carcinoma.

Hepatocellular carcinoma prevention: A worldwide emergence between the opulence of developed countries and the economic constraints of developing nations

Hepatocellular carcinoma (HCC) is the fifth most common neoplasm, the major cause of death in patients with liver cirrhosis, and the third most common cause of cancer-related death in the world. The geographic distribution of HCC varies significantly and 80% of cases occur in developing countries (Far East and South Asia) where the prevalence of viral hepatitis is higher. The treatment of HCC is difficult because most patients are diagnosed when the tumour is in an advanced stage and is not amenable to potential curative therapy, thus prevention is the key to reducing HCC and its related morbidity and mortality. HCC is unique among cancers, occurring mostly in patients with a known risk factor. Ninety percent of HCCs develop in the context of chronic liver diseases and mainly in patients with cirrhosis. Viral hepatitis is the most common cause of HCC worldwide, followed by alcoholic liver disease (ALD) and other causes such as non-alcoholic fatty liver disease (NAFLD), genetic haemocromatosis (GH) and primary biliary cirrhosis in an advanced stage (III-V). In certain areas of the People’s Republic of China, exposure to aflatoxin and HBV infection are thought to be responsible for the extraordinary high risk of HCC. Substantial progresses in the prevention of virusl-related hepatitis (screening of blood units, use of disposable sanitary tools, HBV vaccination) have been achieved in developed countries, but in the same areas, alcohol- and dysmetabolism-related HCCs are emerging problems which require specific interventions in terms of public health measures. In developing countries, economic constraints limit the development of any program for the prevention of viral hepatitis transmission (including health education campaigns, healthcare politics, primary prevention and the improvement of hygienic and sanitary conditions). When viral liver disease is established, only a minority of patients are treated worldwide and benefit a possible preventive effect of medical treatment on HCC development. Thus the real contribution of medical treatment to HCC prevention in patients with chronic viral hepatitis is small. Great efforts are needed to identify more effective medical measures for primary and secondary prevention of HCC.

Differential effects between maotai and ethanol on hepatic gene expression in mice: Possible role of metallothionein and heme oxygenase-1 induction by maotai

Alcohol is a risk factor for liver fibrosis and hepatocellular carcinoma. On the other hand, light alcoholic beverage consumption is believed to be beneficial because of the effects of both alcohol and nonalcoholic components of the beverage. Maotai is a commonly consumed beverage in China containing 53% alcohol. Epidemiological and experimental studies show that Maotai is less toxic to the liver than ethanol alone. To examine the differential effects of Maotai and ethanol, a low dose of Maotai or an equal amount of ethanol (53%, v/v in water, 5 ml/kg) were given to male mice daily for 1 week, and hepatic RNA was extracted for microarray analysis. Approximately 10% of genes on the liver-selective custom array (588 genes) were altered following Maotai or ethanol administration, but Maotai treated livers had fewer alterations compared with ethanol alone. Real-time reverse transcription-polymerase chain reaction confirmed and extended microarray results on selected genes. An induction of metallothionein and heme oxygenase-1 occurred with Maotai, which could not be explained by alcohol consumption alone, whereas the attenuation of ethanol responsive genes such as quinone dehydrogenase, DNA-ligase 1, IGFBP1, and IL-1beta suggests less liver injury occurred with Maotai. The expression of genes related to liver fibrosis, such as cytokeratin-18, was slightly increased by the high dose of ethanol, but was unchanged in the Maotai group. In summary, gene expression analysis indicates that Maotai induces a different response than ethanol alone. The dramatic induction of metallothionein and heme oxygenase-1 with Maotai could be important adaptive responses to reduce alcoholic liver injury.

Molecular pathogenesis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common life-threatening malignancies in the world. This cancer generally arises within the boundaries of well-defined causal factors, of which viral hepatitis infection, aflatoxin exposure, chronic alcohol abuse, and nonalcoholic steatohepatitis are the major risk factors. Despite the identification of these etiological agents, hepatocarcinogenesis remains poorly understood. The molecular mechanisms leading to the development of HCC appear extremely complex and only recently have begun to be elucidated. Currently, surgical resection or liver transplantation offer the best chance of cure for the patient with HCC; however, these therapies are hindered by inability of many of these patients to undergo liver resection, by tumor recurrence and by donor shortages. A lack of suitable therapeutic strategies has led to a greater focus on prevention of HCC using antiviral agents and vaccination. Overall, the current outlook for patients with HCC is bleak; however, a better understanding of the molecular and genetic basis of this cancer should lead to the development of more efficacious therapies.

Southern Europe as an example of interaction between various environmental factors: a systematic review of the epidemiologic evidence

Hepatitis B virus (HBV), hepatitis C virus (HCV) and alcohol consumption are major causes of hepatocellular carcinoma (HCC) worldwide. We performed a systematic review of epidemiologic studies carried out on HCC aetiology in Southern Europe, an area with an intermediate-high prevalence of these agents as well as of putative risk factors such as tobacco smoking, diabetes and obesity. To retrieve the articles, we performed a Medline search for titles and abstracts of articles. After the Medline search, we reviewed the papers and reference lists to identify additional articles. A synergism between HCV infection and HBV infection, overt (hepatitis B virus antigen (HbsAg) positivity) or occult (HBsAg negativity with presence of HBV DNA in liver or serum), is suggested by the results of some studies. The pattern of the risk for HCC due to alcohol intake shows a continuous dose-effect curve without a definite threshold, although most studies found that HCC risk increased only for alcohol consumption above 40-60 g of ethanol per day. Some evidence supports a positive interaction of alcohol intake probably with HCV infection and possibly with HBV infection. A few studies found that coffee has a protective effect on HCC risk due to various risk factors. Some data also support a role of tobacco smoking, diabetes and obesity as single agents or preferably co-factors in causing HCC. In countries with a relatively high alcohol consumption and intermediate levels of HCV and HBV infections (1-3% of population infected by each virus), such as Mediterranean countries, the three main risk factors together account for about 85% of the total HCC cases, leaving little space to other known risk factors, such as haemochromatosis, and to new, still unrecognised, factors as independent causes of HCC.

Ethanol and the tobacco-specific carcinogen, NNK, contribute to signaling in immortalized human pancreatic duct epithelial cells

OBJECTIVES

Smoking is a well-documented risk factor for pancreatic cancer. The tobacco-specific nitrosamine, NNK (4-[methylnitrosamino]-1-[3-pyridyl]-1-butanone), significantly induces pancreatic ductal adenocarcinomas in laboratory rodents. Recent observations suggest that ethanol enhances the tumorigenic effects of smoking. Ethanol consumption is associated with the development of chronic pancreatitis, also considered a predisposing factor for pancreatic ductal adenocarcinoma. Because the precise role of ethanol in pancreatic carcinogenesis is not known, this study sought to elucidate the cumulative effects of ethanol and NNK on particular signal transduction pathways that might play a role in cell proliferation in immortalized human pancreatic duct epithelial cells.

METHODS

The HPDE6-c7 cells are developed from pancreatic duct epithelial cells, which are the putative cells of origin of pancreatic ductal adenocarcinoma. Cell proliferation assays, Western blot, and cyclic adenosine monophosphate assays were used to demonstrate the effects of ethanol and NNK treatments on these cells.

RESULTS

Ethanol cotreatments enhanced the NNK-induced proliferation of these cells. This response was inhibited by the adenylyl cyclase, protein kinase A, mitogen-activated protein kinase (p42/p44), and epidermal growth factor receptor-specific tyrosine kinase inhibitors. Cotreatments of NNK and ethanol also increased cyclic adenosine monophosphate accumulation, cAMP response element-binding family of proteins and mitogen-activated protein kinase phosphorylation, and protein kinase A activation.

CONCLUSIONS

These findings suggest a potential role for these pathways contributing to the development of smoking- and alcohol-related pancreatic carcinogenesis.

Alcohol and cancer

A causal association has been established between alcohol consumption and cancers of the oral cavity, pharynx, larynx, oesophagus, liver, colon, rectum, and, in women, breast; an association is suspected for cancers of the pancreas and lung. Evidence suggests that the effect of alcohol is modulated by polymorphisms in genes encoding enzymes for ethanol metabolism (eg, alcohol dehydrogenases, aldehyde dehydrogenases, and cytochrome P450 2E1), folate metabolism, and DNA repair. The mechanisms by which alcohol consumption exerts its carcinogenic effect have not been defined fully, although plausible events include: a genotoxic effect of acetaldehyde, the main metabolite of ethanol; increased oestrogen concentration, which is important for breast carcinogenesis; a role as solvent for tobacco carcinogens; production of reactive oxygen species and nitrogen species; and changes in folate metabolism. Alcohol consumption is increasing in many countries and is an important cause of cancer worldwide.

Alcohol and liver cancer

Hepatocellular carcinoma is the eighth most frequent cancer in the world, accounting for approximately 500,000 deaths per year. Unlike many malignancies, hepatocellular carcinoma occurs predominantly within the context of known risk factors, with hepatic cirrhosis being the most common precursor to the development of hepatocellular carcinoma. After ethanol ingestion, the liver represents the major site of metabolism. Ethanol metabolism by alcohol dehydrogenase leads to the generation of acetaldehyde and free radicals that bind rapidly to numerous cellular targets, including components of cell signaling pathways and DNA. In addition to direct DNA damage, acetaldehyde depletes glutathione, an antioxidant involved in detoxification. Chronic ethanol abuse leads to induction of hepatocyte microsomal cytochrome P450 2E1, an enzyme that metabolizes ethanol to acetaldehyde and, in doing so, causes further free radical production and aberrant cell function. Cytochrome P450 2E1-dependent ethanol metabolism is also associated with activation of procarcinogens, changes in cell cycle, nutritional deficiencies, and altered immune system responses. The identification of oxidative stress in mediating many deleterious effects of ethanol in the liver has led to renewed interest in the use of dietary antioxidants as therapeutic agents. Included in this group are S-adenosyl-L-methionine and plant-derived flavanoids.