Molecular hepatic carcinogenesis: impact of inflammation

Matrix metalloproteinase-21 promotes metastasis via increasing the recruitment and M2 polarization of macrophages in HCC

MMP-21 is a newly identified member of the matrix metalloproteinase family and has been reported to regulate both embryonic development and tumor progression. However, the roles of MMP-21 in hemofiltrate C-C chemokine (HCC) remain largely unclear. In this study, we used western blot, qPCR and immunohistochemistry (IHC) to determine the upregulation of MMP-21 in HCC tissues, and showed that the increase in MMP-21 was associated with vascular invasion and poor prognosis. Although changing levels of MMP-21 in HCC cell lines had no significant effect on cell migration or invasion abilities in in vitro transwell tests, both IHC analysis and in vivo mouse models proved that upregulated MMP-21 promoted metastasis. Functional enrichments of MMP-21 using The Cancer Genome Atlas (TCGA) data suggested that MMP-21 might regulate metastasis via macrophages. Further experiments proved that MMP-21 enhanced macrophage recruitment by increasing CCL-14 levels and promoted M2-type polarization of macrophage by elevating the expression of CSF-1 and FGF-1. Taken together, this study revealed that MMP-21 controlled the tumor microenvironment remodeling and functional regulation of macrophages to regulate HCC metastasis.

A Logistic Regression Model for Noninvasive Prediction of AFP-Negative Hepatocellular Carcinoma

α-Fetoprotein is commonly used in the diagnosis of hepatocellular carcinoma. However, the diagnostic significance of α-fetoprotein has been questioned because a number of patients with hepatocellular carcinoma are α-fetoprotein negative. It is therefore necessary to develop novel noninvasive techniques for the early diagnosis of hepatocellular carcinoma, particularly when α-fetoprotein level is low or negative. The current study aimed to evaluate the diagnostic efficiency of hematological parameters to determine which can act as surrogate markers in α-fetoprotein-negative hepatocellular carcinoma. Therefore, a retrospective study was conducted on a training set recruited from Zhongnan Hospital of Wuhan University-including 171 α-fetoprotein-negative patients with hepatocellular carcinoma and 102 healthy individuals. The results show that mean values of mean platelet volume, red blood cell distribution width, mean platelet volume-PC ratio, neutrophils-lymphocytes ratio, and platelet count-lymphocytes ratio were significantly higher in patients with hepatocellular carcinoma in comparison to the healthy individuals. Most of these parameters showed moderate area under the curve in α-fetoprotein-negative patients with hepatocellular carcinoma, but their sensitivities or specificities were not satisfactory enough. So, we built a logistic regression model combining multiple hematological parameters. This model presented better diagnostic efficiency with area under the curve of 0.922, sensitivity of 83.0%, and specificity of 93.1%. In addition, the 4 validation sets from different hospitals were used to validate the model. They all showed good area under the curve with satisfactory sensitivities or specificities. These data indicate that the logistic regression model combining multiple hematological parameters has better diagnostic efficiency, and they might be helpful for the early diagnosis for α-fetoprotein-negative hepatocellular carcinoma.

Diagnostic and therapeutic potential of the gut microbiota in patients with early hepatocellular carcinoma

The gut microbiota is involved in the maintenance of the homeostasis of the human body and its alterations are associated with the development of different pathological conditions. The liver is the organ most exposed to the influence of the gut microbiota, and recently important connections between the intestinal flora and hepatocellular carcinoma (HCC) have been described. In fact, HCC is commonly associated with liver cirrhosis and develops in a microenvironment where inflammation, immunological alterations, and cellular aberrations are dramatically evident. Prevention and diagnosis in the earliest stages are still the most effective weapons in fighting this tumor. Animal models show that the gut microbiota can be involved in the promotion and progression of HCC directly or through different pathogenic mechanisms. Recent data in humans have confirmed these preclinical findings, shedding new light on HCC pathogenesis. Limitations due to the different experimental design, the ethnic and hepatological setting make it difficult to compare the results and draw definitive conclusions, but these studies lay the foundations for a pathogenetic redefinition of HCC. Therefore, it is evident that the characterization of the gut microbiota and its modulation can have an enormous diagnostic, preventive, and therapeutic potential, especially in patients with early stage HCC.

Altered expression of COX-2 and TNF-α in patients with hepatocellular carcinoma

BACKGROUND AND AIM

hepatocellular carcinoma is a type of cancer related with inflammation, as 90% of cases develop in a chronic inflammation condition. Excess inflammation can affect tissue homeostasis. Cytokines and inflammatory mediators are immunological components that can influence the functioning of cells and tissues. In addition, the estrogen receptor appears to play an important role in hepatocarcinogenesis. The aim of the study was to evaluate the expression of inflammatory markers and ER in patients with hepatocellular carcinoma.

METHODS

data from 143 patients of ISCMPA were analyzed. Immunohistochemistry was performed of cyclooxygenase-2 enzyme (COX-2), nuclear factor kappa B (NF-κB), tumor necrosis factor alpha (TNF-α) and ER in paraffin-embedded hepatic tissue. The percentage of the stained area, intensity of staining and of the number of ER positive nuclei were evaluated using the ImageJ 1.50 software.

RESULTS AND CONCLUSION

there was a significant difference between the groups in terms of the percentage of marked area (p = 0.040) for COX-2 and the intensity of staining of TNF-α (p = 0.030). No significant differences were observed in any of other parameters evaluated. In conclusion, COX-2 and TNF-α are possible markers that should be further studied to determine their immunohistochemical profile and role in HCC development.

Alcoholic Liver Disease Accelerates Early Hepatocellular Cancer in a Mouse Model

HCC is a rapidly increasing cancer worldwide. Most HCC rises in the setting of chronic and advanced liver disease caused by viral hepatitis, alcohol use, non-alcoholic liver disease or their combination. We found that in the mouse model, alcohol alone does not induce HCC, however, it can promote HCC development after a carcinogen exposure. Multiple mechanisms are involved in carcinogenesis and alcohol affects many of those including epithelial-mesenchymal transition, cancer stem marker expression and inflammation as evidenced in our HCC model.

Assessment of high-sensitivity C-reactive protein tests for the diagnosis of hepatocellular carcinoma in patients with hepatitis B-associated liver cirrhosis

Hepatocellular carcinoma (HCC) is a common malignant tumor worldwide, with high morbidity and mortality. Chronic infection with hepatitis B virus (HBV) is a major risk factor for the development of hepatocellular carcinoma and the majority (~80%) of hepatocellular carcinoma patients in China exhibit co-morbidity with HBV-associated liver cirrhosis. The goal of reliable early diagnostic and prognostic techniques for HBV-associated HCC remains unrealized. The aim of the present study was to explore the efficacy of serum high-sensitivity C-reactive protein (hs-CRP) tests in the early diagnosis of HCC in patients with HBV-associated liver cirrhosis. A cohort of 493 patients with HBV-associated liver disease was divided into three groups: Chronic HBV (CHB) group; liver cirrhosis without HCC (LC) group; and liver cirrhosis with HCC (HCC) group. A further 47 healthy individuals comprised the healthy control (CN) group. Comparative analyses of clinical symptoms, histopathology, ultrasound imagery, computed tomography, magnetic resonance imaging, biochemistry [α-fetoprotein (AFP) and liver function enzymes], and hs-CRP tests were conducted across these four groups. Immunohistochemical analysis showed that CRP is strongly expressed in HCC tumor tissue, but is not expressed elsewhere. Analyses of the correlations between serum hs-CRP levels and HCC clinical parameters indicated that there was no correlation between serum hs-CRP levels, tumor Edmondson grade, tumor-node-metastasis stage and AFP status. Serum hs-CRP and AFP levels were found to be significantly elevated in the HCC group compared to those in the LC, CHB and CN groups (P<0.01). Receiver operator characteristic analysis showed that measurement of serum hs-CRP could differentiate HCC from HBV-associated liver cirrhosis, as well as increase the accuracy of HCC diagnoses. Additionally, measurement of hs-CRP and AFP together improved diagnostic accuracy for HCC compared with either test alone. Serum hs-CRP could have potential as an effective diagnostic tool to complement AFP in diagnosing HCC and improving the identification of AFP-negative HCC in patients with HBV-associated liver cirrhosis. The present findings may facilitate the earlier diagnosis of hepatocellular carcinoma, permitting more effective treatment and a broader spectrum of treatment modalities for patients with advanced hepatic disease.

Hepatocellular carcinoma: Exploring the impact of ethnicity on molecular biology

Hepatocellular carcinoma (HCC) is the sixth most common cancer in the world and the third leading cause of cancer-related death. The high rate of diagnosis in non-curable stages and the lack of novel active treatments make it necessary to review all the possible sources of misleading results in this scenario. The incidence of HCC shows clear geographical variation with higher annual incidence in Asia and Africa than in Western countries; we aimed to review the literature to find if there are different trends in the main activated molecular pathways. Hyperactivation of RAS/RAF/MEK/ERK and PI3K/AKT/mTOR signalling and epithelial to mesenchymal transition (EMT) process are more prevalent in the Western population; however, fibroblast growth factor (FGF), transforming growth factor β (TGFβ) and Notch pathways seems to be more relevant in Asian population. Whether these variations just reflect the distinct distribution of known causes of HCC or proper ethnical differences remain to be elucidated. Nevertheless, these clearly different patterns are relevant to regional or worldwide clinical trial design. If this information is neglected by sponsors and researchers the rate of failure in HCC trials will not improve.

Elevated Serum Levels of the Antiapoptotic Protein Decoy-Receptor 3 Are Associated with Advanced Liver Disease

Background. Decoy-receptor 3 (DcR3) exerts antiapoptotic and immunomodulatory function and is overexpressed in neoplastic and inflammatory conditions. Serum DcR3 (sDcR3) levels during the chronic hepatitis/cirrhosis/hepatocellular carcinoma (HCC) sequence have not been explored. Objective. To assess the levels and significance of sDcR3 protein in various stages of chronic liver disease. Methods. We compared sDcR3 levels between healthy controls and patients with chronic viral hepatitis (CVH), decompensated cirrhosis (DC), and HCC. Correlations between sDcR3 levels and various patient- and disease-related factors were analyzed. Results. sDcR3 levels were significantly higher in patients with CVH than in controls (P < 0.01). sDcR3 levels were elevated in DC and HCC, being significantly higher compared not only to controls (P < 0.001 for both) but to CVH patients as well (P < 0.001 for both). In addition, DcR3 protein was detected in large quantities in the ascitic fluid of cirrhotics. In patients with CVH, sDcR3 significantly correlated to fibrosis severity, as estimated by Ishak score (P = 0.019) or by liver stiffness measured with elastography (Spearman r = 0.698, P < 0.001). In cirrhotic patients, significant positive correlations were observed between sDcR3 levels and markers of severity of hepatic impairment, including MELD score (r = 0.653, P < 0.001). Conclusions. Circulating levels of DcR3 are elevated during chronic liver disease and correlate with severity of liver damage. sDcR3 may serve as marker for liver fibrosis severity and progression to end-stage liver disease.

Genomic instability in human cancer: Molecular insights and opportunities for therapeutic attack and prevention through diet and nutrition

Genomic instability can initiate cancer, augment progression, and influence the overall prognosis of the affected patient. Genomic instability arises from many different pathways, such as telomere damage, centrosome amplification, epigenetic modifications, and DNA damage from endogenous and exogenous sources, and can be perpetuating, or limiting, through the induction of mutations or aneuploidy, both enabling and catastrophic. Many cancer treatments induce DNA damage to impair cell division on a global scale but it is accepted that personalized treatments, those that are tailored to the particular patient and type of cancer, must also be developed. In this review, we detail the mechanisms from which genomic instability arises and can lead to cancer, as well as treatments and measures that prevent genomic instability or take advantage of the cellular defects caused by genomic instability. In particular, we identify and discuss five priority targets against genomic instability: (1) prevention of DNA damage; (2) enhancement of DNA repair; (3) targeting deficient DNA repair; (4) impairing centrosome clustering; and, (5) inhibition of telomerase activity. Moreover, we highlight vitamin D and B, selenium, carotenoids, PARP inhibitors, resveratrol, and isothiocyanates as priority approaches against genomic instability. The prioritized target sites and approaches were cross validated to identify potential synergistic effects on a number of important areas of cancer biology.

Translational Implications of the Alcohol-Metabolizing Enzymes, Including Cytochrome P450-2E1, in Alcoholic and Nonalcoholic Liver Disease

Fat accumulation (hepatic steatosis) in alcoholic and nonalcoholic fatty liver disease is a potentially pathologic condition which can progress to steatohepatitis (inflammation), fibrosis, cirrhosis, and carcinogenesis. Many clinically used drugs or some alternative medicine compounds are also known to cause drug-induced liver injury, which can further lead to fulminant liver failure and acute deaths in extreme cases. During liver disease process, certain cytochromes P450 such as the ethanol-inducible cytochrome P450-2E1 (CYP2E1) and CYP4A isozymes can be induced and/or activated by alcohol and/or high-fat diets and pathophysiological conditions such as fasting, obesity, and diabetes. Activation of these P450 isozymes, involved in the metabolism of ethanol, fatty acids, and various drugs, can produce reactive oxygen/nitrogen species directly and/or indirectly, contributing to oxidative modifications of DNA/RNA, proteins and lipids. In addition, aldehyde dehydrogenases including the mitochondrial low Km aldehyde dehydrogenase-2 (ALDH2), responsible for the metabolism of acetaldehyde and lipid aldehydes, can be inactivated by various hepatotoxic agents. These highly reactive acetaldehyde and lipid peroxides, accumulated due to ALDH2 suppression, can interact with cellular macromolecules DNA/RNA, lipids, and proteins, leading to suppression of their normal function, contributing to DNA mutations, endoplasmic reticulum stress, mitochondrial dysfunction, steatosis, and cell death. In this chapter, we specifically review the roles of the alcohol-metabolizing enzymes including the alcohol dehydrogenase, ALDH2, CYP2E1, and other enzymes in promoting liver disease. We also discuss translational research opportunities with natural and/or synthetic antioxidants, which can prevent or delay the onset of inflammation and liver disease.

S100A9 promotes human hepatocellular carcinoma cell growth and invasion through RAGE-mediated ERK1/2 and p38 MAPK pathways

S100A9 belongs to the S100 family of calcium-binding proteins and is over-expressed in many human tumors including hepatocellular carcinoma (HCC). Recent study demonstrated that S100A9 is significantly elevated and is associated with tumor differentiation and vascular invasion in HCC. The functional role of S100A9 is, however, poorly understood. Here, we demonstrated that S100A9 treatment increased viability, invasiveness and clone formation in three HCC cell lines (HepG2, SMMC-7721 and Huh7). S100A9 also promoted tumor growth in vivo by a xenograft mouse model. In addition, we observed a co-localization of S100A9 with receptor for advanced glycation end products (RAGE) in human HCC intratumoral tissues and an interaction of S100A9 with RAGE in vitro. Treatment with RAGE blocking antibody blocked the enhanced viability, invasion, clone formation and tumor growth in vivo resulted by S100A9, suggesting that these effects were mediated via RAGE ligation. In order to investigate the signaling pathways, mitogen-activated protein kinase (MAPK) phosphorylation was characterized. S100A9 caused a significant increase in p-p38 and p-ERK1/2 levels, and inhibition of which blocked enhanced invasion and viability resulted by S100A9, respectively. Furthermore, treatment with RAGE blocking antibodies also abrogated the S100A9-induced p38 and ERK1/2 activation, suggesting that S100A9-induced MAPK activation is mediated via RAGE ligation. Our data demonstrate that S100A9 binds to RAGE and stimulates RAGE-dependent MAPK signaling cascades, promoting cell growth and invasion in HCC.

The role of inflammation and liver cancer

Persistent inflammation is known to promote and exacerbate malignancy. Primary liver cancer, mostly hepatocellular carcinoma (HCC), is a clear example of inflammation-related cancer as more than 90 % of HCCs arise in the context of hepatic injury and inflammation. HCC represents the fifth most common malignancy and the third leading cause of cancer-related death worldwide with about one million new cases diagnosed every year with almost an equal number of deaths. Chronic unresolved inflammation is associated with persistent hepatic injury and concurrent regeneration, leading to sequential development of fibrosis, cirrhosis, and eventually HCC. Irrespective of the intrinsic differences among various etiological factors, a common denominator at the origin of HCC is the perpetuation of a wound-healing response activated by parenchymal cell death and the resulting inflammatory cascade. Hence, the identification of fundamental inflammatory signaling pathways causing transition from chronic liver injury to dysplasia and HCC could depict new predictive biomarkers and targets to identify and treat patients with chronic liver inflammation. This chapter critically discusses the roles of several major cytokines, chemokines, growth factors, transcription factors, and enzymes as well as a distinct network of inflammatory signaling pathways in the development and progression of HCC. It also highlights and analyzes preclinical animal studies showing innovative approaches of targeting inflammatory mediators and signaling by a variety of natural compounds and synthetic agents to achieve effective therapy as well as prevention of hepatic malignancy. Additionally, current limitations and potential challenges associated with the inhibition of inflammatory signaling as well as future directions of research to accelerate clinical development of anti-inflammatory agents to prevent and treat liver cancer are presented.

Expression quantitative trait loci in long non-coding RNA ZNRD1-AS1 influence both HBV infection and hepatocellular carcinoma development

Zinc ribbon domain containing 1 (ZNRD1), cloned from human leukocyte antigen (HLA) region, may play integral roles in diverse processes including immune response against HBV infection and hepatocarcinogenesis. ZNRD1-AS1 (ZNRD1 antisense RNA 1) may be an important regulator of ZNRD1. By bioinformatics analyses, we identified that several single nucleotide polymorphisms (SNPs) in ZNRD1-AS1 may be expression quantitative trait loci (eQTLs) for ZNRD1. In this study, we hypothesized that these eQTLs SNPs in ZNRD1-AS1 may influence both chronic HBV infection and hepatocellular carcinoma (HCC) development. We designed a case-control study of 1300 HBV-positive HCC patients, 1344 HBV persistent carriers and, 1344 HBV natural clearance subjects to test the associations of three ZNRD1 eQTLs SNPs (rs3757328, rs6940552 and, rs9261204) in ZNRD1-AS1 with the risk of both chronic HBV infection and HCC. Logistic regression analyses in additive genetic model showed that variant alleles of all the three SNPs increased host HCC risk, whereas variant allele of rs3757328 was associated with HBV clearance. Moreover, the haplotype containing variant alleles of the three SNPs was significantly associated with both HCC development (adjusted OR = 1.18, 95% CI = 1.01-1.38, P = 0.035) and HBV clearance (adjusted OR = 0.83, 95% CI = 0.71-0.96, P = 0.013), when compared with the most frequent haplotype. In vitro experiments showed that ZNRD1 knockdown inhibited the expression of HBV mRNA and promoted proliferation of HepG2.2.15 cells. These findings suggest that ZNRD1 regulatory SNPs may be susceptibility makers for risk of both chronic HBV infection and HCC.

Inflammation and oxidative stress markers and esophageal adenocarcinoma incidence in a Barrett's esophagus cohort

BACKGROUND

Persons with Barrett's esophagus experience increased risk of esophageal adenocarcinoma. Prediagnostic inflammation markers predict several cancers, but their role in predicting esophageal adenocarcinoma is unknown.

METHODS

We investigated whether biomarkers of inflammation [C-reactive protein (CRP), interleukin-6 (IL6), soluble tumor necrosis factor (sTNF) receptors I and II], and of oxidative stress (F2-isoprostanes) predicted progression to esophageal adenocarcinoma in a prospective cohort of 397 patients with Barrett's esophagus, 45 of whom developed esophageal adenocarcinoma. Biomarkers were measured in stored plasma samples from two time points during follow-up, the mean of which served as the primary predictor. Adjusted hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox regression.

RESULTS

CRP level above the median was associated with an 80% increased risk of esophageal adenocarcinoma. The HR and 95% CI adjusted for age, gender, and further adjusted for waist-hip ratio and smoking were 1.98 (1.05-3.73) and 1.77 (0.93-3.37), respectively, with Ptrend for continuous CRP = 0.04. Persons with IL6 levels above the median also had almost 2-fold increased risk [HR and 95% CI adjusted for age and gender, and further adjusted for waist-hip ratio and smoking were 1.95 (1.03-3.72) and 1.79 (0.93-3.43), respectively, but no evidence of a trend was observed]. Concentrations of TNF receptors and F2-isoprostanes were not associated with esophageal adenocarcinoma risk.

CONCLUSIONS

Further research is needed to evaluate the role of inflammation and associated markers in esophageal adenocarcinoma development in persons with Barrett's esophagus.

IMPACT

This prospective study suggests that inflammation markers, particularly CRP and IL6, may help identify persons at higher risk of progression to esophageal adenocarcinoma.

C-reactive protein genetic polymorphisms increase susceptibility to HBV-related hepatocellular carcinoma in a Chinese population

Chronic inflammation has been implicated in the etiology of hepatocellular carcinoma (HCC). The C-reactive protein (CRP) genetic polymorphisms affected serum CRP concentrations and elevation of CRP has been considered as the hallmark of acute and chronic inflammation. In this study, we investigated the association between CRP genetic polymorphisms and HBV-related HCC risk in a Chinese population. Two polymorphisms in the CRP gene (rs3093059 and rs2794521) were examined in 192 HBV-related HCC patients, 277 non-HCC patients with HBV infection, and 192 healthy controls using polymerase chain reaction-restriction fragment length polymorphism method. DNA direct sequencing was performed to validate the results of genotyping. We found that there were significant differences in the genotype and allele frequencies of the CRP gene rs3093059 polymorphism between the HBV-related HCC patients and the non-HCC patients with HBV infection. The rs3093059 TC genotype was associated with a significant increased HCC risk as compared with the TT genotype (odds ratio (OR) = 1.98, 95 % confidence interval (CI) 1.32-2.95, P = 0.001). The rs3093059 C allele was correlated with a significant increased HCC risk as compared with the T allele (OR = 1.65, 95 % CI 1.16-2.30, P = 0.005). Furthermore, the rs3093059 TC combined with CC genotypes were found to correlate with a significant increased HCC risk compared with the TT genotype in dominant model (OR = 1.92, 95 % CI 1.29-2.82, P = 0.001). However, we did not find any significant effect of CRP rs2794521 polymorphism on HCC risk in this population. In haplotype analysis between HBV-related HCC patients and non-HCC patients with HBV infection, the TC haplotype was found correlated with a significant increased HCC risk (OR = 1.750, 95 % CI 1.234-2.480, P = 0.001). The results suggested that the CRP rs3093059 polymorphism may contribute to increased HCC risk in HBV-infected patients in the Chinese population. Further large and well-designed studies in diverse ethnic populations are needed to confirm our results.

The co-localization of HBx and COXIII upregulates COX-2 promoting HepG2 cell growth

HBx is a multifunctional regulator that interacts with host factors to contribute to the development of hepatocellular carcinoma. In this study, to explore the co-localization of HBx and COXIII in HepG2 cells and to investigate the molecular mechanism of HBx in HepG2 cell growth promotion, we first constructed a HepG2 cell line stably expressing the HBx gene in vitro by lentivirus vectors. In addition, we found that HBx co-localized with the inner mitochondrial protein, COXIII, in HepG2 cells by confocal laser scanning microscopy. It led to changes of mitochondrial biogenesis and morphology, including upregulation of COXIII protein expression, increased cytochrome c oxidase activity and higher mitochondrial membrane potential. The upregulation of COX-2 caused by HBx through generation of mitochondrial reactive oxygen species promoted cell growth. Thus, we conclude that co-localization of HBx and COXIII leads to upregulation of COX-2 that promotes HepG2 cell growth. Such a mechanism provides deeper insights into the molecular mechanism of HBV-associated hepatocellular carcinoma.

Loss of the nucleosome-binding protein HMGN1 affects the rate of N-nitrosodiethylamine-induced hepatocarcinogenesis in mice

We report that HMGN1, a nucleosome-binding protein that affects chromatin structure and function, affects the growth of N-nitrosodiethylamine (DEN)-induced liver tumors. Following a single DEN injection at 2 weeks of age, Hmgn1(tm1/tm1) mice, lacking the nucleosome-binding domain of HMGN1, had earlier signs of liver tumorigenesis than their Hmgn1(+/+) littermates. Detailed gene expression profiling revealed significant differences between DEN-injected and control saline-injected mice, but only minor differences between the injected Hmgn1(tm1/tm1) mice and their Hmgn1(+/+) littermates. Pathway analysis revealed that the most significant process affected by loss of HMGN1 involves the lipid/sterol metabolic pathway. Our study indicates that in mice, loss of HMGN1 leads to transcription changes that accelerate the progression of DEN-induced hepatocarcinogenesis, without affecting the type of tumors or the final total tumor burden of these mice.

IMPLICATIONS

Loss of HMGN1 leads to accelerated progression of DEN-induced hepatocarcinogenesis in mice.

Can non-selective beta-blockers prevent hepatocellular carcinoma in patients with cirrhosis?

Hepatocellular carcinoma is the main liver-related cause of death in patients with compensated cirrhosis. The early phases are asymptomatic and the prognosis is poor, which makes prevention essential. We propose that non-selective beta-blockers decrease the incidence and growth of hepatocellular carcinoma via a reduction of the inflammatory load from the gut to the liver and inhibition of angiogenesis. Due to their effect on the portal pressure, non-selective beta-blockers are used for prevention of esophageal variceal bleeding. Recently, non-hemodynamic effects of beta-blockers have received increasing attention. Blockage of β-adrenoceptors in the intestinal mucosa and gut lymphatic tissue together with changes in type and virulence of the intestinal microbiota lead to reduced bacterial translocation and a subsequent decrease in the portal load of pathogen-associated molecular patterns. This may reduce hepatic inflammation. Blockage of β-adrenoceptors also decrease angiogenesis by inhibition of vascular endothelial growth factors. Because gut-derived inflammation and neo-angiogenesis are important in hepatic carcinogenesis, non-selective beta-blockers can potentially reduce the development and growth of hepatocellular carcinoma. Rodent and in vitro studies support the hypothesis, but clinical verification is needed. Different study designs may be considered. The feasibility of a randomized controlled trial is limited due to the necessary large number of patients and long follow-up. Observational studies carry a high risk of bias. The meta-analytic approach may be used if the incidence and mortality of hepatocellular carcinoma can be extracted from trials on variceal bleeding and if the combined sample size and follow up is sufficient.

Non-alcoholic steatohepatitis and preneoplastic lesions develop in the liver of obese and hypertensive rats: suppressing effects of EGCG on the development of liver lesions

Non-alcoholic steatohepatitis (NASH), which involves hepatic inflammation and fibrosis, is associated with liver carcinogenesis. The activation of the renin-angiotensin system (RAS), which plays a key role in blood pressure regulation, promotes hepatic fibrogenesis. In this study, we investigated the effects of (-)-epigallocatechin-3-gallate (EGCG), a major component of green tea catechins, on the development of glutathione S-transferase placental form (GST-P)-positive (GST-P(+)) foci, a hepatic preneoplastic lesion, in SHRSP.Z-Lepr(fa)/IzmDmcr (SHRSP-ZF) obese and hypertensive rats. Male 7-week-old SHRSP-ZF rats and control non-obese and normotensive WKY rats were fed a high fat diet and received intraperitoneal injections of carbon tetrachloride twice a week for 8weeks. The rats were also provided tap water containing 0.1% EGCG during the experiment. SHRSP-ZF rats presented with obesity, insulin resistance, dyslipidemia, an imbalance of adipokines in the serum, and hepatic steatosis. The development of GST-P(+) foci and liver fibrosis was markedly accelerated in SHRSP-ZF rats compared to that in control rats. Additionally, in SHRSP-ZF rats, RAS was activated and inflammation and oxidative stress were induced. Administration of EGCG, however, inhibited the development of hepatic premalignant lesions by improving liver fibrosis, inhibiting RAS activation, and attenuating inflammation and oxidative stress in SHRSP-ZF rats. In conclusion, obese and hypertensive SHRSP-ZF rats treated with a high fat diet and carbon tetrachloride displayed the histopathological and pathophysiological characteristics of NASH and developed GST-P(+) foci hepatic premalignant lesions, suggesting the model might be useful for the evaluation of NASH-related liver tumorigenesis. EGCG might also be able to prevent NASH-related liver fibrosis and tumorigenesis.