Expression of epidermal growth factor and its receptor in cirrhotic liver disease

Evaluation of the modulating effect of epidermal growth factor receptor inhibitor cetuximab in carbon-tetrachloride induce hepatic fibrosis in rats

Liver fibrosis, developed in almost all chronic liver injuries. Epidermal growth factor receptors (EGFR) have been thought to contribute to cirrhosis and liver fibrosis. Therefore, using a rat model of carbon tetrachloride (CCl4)-induced liver fibrogenesis, we investigated the preventive effects of cetuximab, an inhibitor of the EGF receptor (EGFR). Ameliorative effects of cetuximab were examined in rats, brought on by biweekly doses of 50 mg/kg of carbon tetrachloride (CCl4). There were a total of 24 male Long Evans rats split up into four distinct groups such as control, CCl4, control+cetuximab and CCl4+cetuximab. After two weeks of treatment with cetuximab (100 μg/kg), samples of tissue and blood were taken after all the rats had been sacrificed. Plasma samples were examined for the biochemical indicators of inflammation and oxidative stress. Histological staining on liver sections was performed for morphologic pathologies, and related genes expressions analysis were done with RT-PCR in liver tissue. The findings showed that cetuximab could raise the levels of glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) and considerably lower the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), malondialdehyde (MDA), and nitric oxide (NO). Sirius red staining and hematoxylin-eosin (H&E) displayed that cetuximab therapy reduced the inflammatory cells infiltration and enhanced fibrotic lesions. In the meantime, cetuximab therapy also dramatically reduces the expression of genes linked to inflammation in the liver tissue, including NF-кB, iNOS, IL-6, TNF-α, and TGF-β. To sum up, the anti-inflammatory, antifibrotic, and antioxidant properties of cetuximab confer curative efficacy against liver fibrosis.

Cytoplasmic retention of the DNA/RNA-binding protein FUS ameliorates organ fibrosis in mice

Uncontrolled accumulation of extracellular matrix leads to tissue fibrosis and loss of organ function. We previously demonstrated in vitro that the DNA/RNA-binding protein fused in sarcoma (FUS) promotes fibrotic responses by translocating to the nucleus, where it initiates collagen gene transcription. However, it is still not known whether FUS is profibrotic in vivo and whether preventing its nuclear translocation might inhibit development of fibrosis following injury. We now demonstrate that levels of nuclear FUS are significantly increased in mouse models of kidney and liver fibrosis. To evaluate the direct role of FUS nuclear translocation in fibrosis, we used mice that carry a mutation in the FUS nuclear localization sequence (FUSR521G) and the cell-penetrating peptide CP-FUS-NLS that we previously showed inhibits FUS nuclear translocation in vitro. We provide evidence that FUSR521G mice or CP-FUS-NLS-treated mice showed reduced nuclear FUS and fibrosis following injury. Finally, differential gene expression analysis and immunohistochemistry of tissues from individuals with focal segmental glomerulosclerosis or nonalcoholic steatohepatitis revealed significant upregulation of FUS and/or collagen genes and FUS protein nuclear localization in diseased organs. These results demonstrate that injury-induced nuclear translocation of FUS contributes to fibrosis and highlight CP-FUS-NLS as a promising therapeutic option for organ fibrosis.

Potential Hepatoprotective Effects of Chamaecyparis lawsoniana against Methotrexate-Induced Liver Injury: Integrated Phytochemical Profiling, Target Network Analysis, and Experimental Validation

Methotrexate (MTX) therapy encounters significant limitations due to the significant concern of drug-induced liver injury (DILI), which poses a significant challenge to its usage. To mitigate the deleterious effects of MTX on hepatic function, researchers have explored plant sources to discover potential hepatoprotective agents. This study investigated the hepatoprotective effects of the ethanolic extract derived from the aerial parts of Chamaecyparis lawsoniana (CLAE) against DILI, specifically focusing on MTX-induced hepatotoxicity. UPLC-ESI-MS/MS was used to identify 61 compounds in CLAE, with 31 potential bioactive compounds determined through pharmacokinetic analysis. Network pharmacology analysis revealed 195 potential DILI targets for the bioactive compounds, including TP53, IL6, TNF, HSP90AA1, EGFR, IL1B, BCL2, and CASP3 as top targets. In vivo experiments conducted on rats with acute MTX-hepatotoxicity revealed that administering CLAE orally at 200 and 400 mg/kg/day for ten days dose-dependently improved liver function, attenuated hepatic oxidative stress, inflammation, and apoptosis, and reversed the disarrayed hepatic histological features induced by MTX. In general, the findings of the present study provide evidence in favor of the hepatoprotective capabilities of CLAE in DILI, thereby justifying the need for additional preclinical and clinical investigations.

Potential therapeutic target of EGF on bile duct ligation model and biliary atresia children

BACKGROUND

The pathogenesis of liver fibrosis in biliary atresia (BA) is unclear. Epidermal growth factor (EGF) plays a vital role in liver fibrosis. This study aims to investigate the expression of EGF and the mechanisms of its pro-fibrotic effects in BA.

METHODS

EGF levels in serum and liver samples of BA and non-BA children were detected. Marker proteins of EGF signaling and epithelial-mesenchymal transition (EMT) in liver sections were evaluated. Effects of EGF on intrahepatic cells and the underlying mechanisms were explored in vitro. Bile duct ligation (BDL) mice with/without EGF antibody injection were used to verify the effects of EGF on liver fibrosis.

RESULTS

Serum levels and liver expression of EGF elevated in BA. Phosphorylated EGF receptor (p-EGFR) and extracellular regulated kinase 1/2 (p-ERK1/2) increased. In addition, EMT and proliferation of biliary epithelial cells were present in BA liver. In vitro, EGF induced EMT and proliferation of HIBEpic cells and promoted IL-8 expression in L-02 cells by phosphorylating ERK1/2. And EGF activated LX-2 cells. Furthermore, EGF antibody injection reduced p-ERK1/2 levels and alleviated liver fibrosis in BDL mice.

CONCLUSION

EGF is overexpressed in BA. It aggravates liver fibrosis through EGF/EGFR-ERK1/2 pathway, which may be a therapeutic target for BA.

IMPACT

The exact pathogenesis of liver fibrosis in BA is unknown, severely limiting the advancement of BA treatment strategies. This study revealed that serum and liver tissue levels of EGF were increased in BA, and its expression in liver tissues was correlated with the degree of liver fibrosis. EGF may promote EMT and proliferation of biliary epithelial cells and induce IL-8 overexpression in hepatocytes through EGF/EGFR-ERK1/2 signaling pathway. EGF can also activate HSCs in vitro. The EGF/EGFR-ERK1/2 pathway may be a potential therapeutic target for BA.

New Insight Into Mechanisms of Hepatic Encephalopathy: An Integrative Analysis Approach to Identify Molecular Markers and Therapeutic Targets

Hepatic encephalopathy (HE) is a set of complex neurological complications that arise from advanced liver disease. The precise molecular and cellular mechanism of HE is not fully understood. Differentially expressed genes (DEGs) from microarray technologies are powerful approaches to obtain new insight into the pathophysiology of HE. We analyzed microarray data sets of cirrhotic patients with HE from Gene Expression Omnibus to identify DEGs in postmortem cerebral tissues. Consequently, we uploaded significant DEGs into the STRING to specify protein-protein interactions. Cytoscape was used to reconstruct the genetic network and identify hub genes. Target genes were uploaded to different databases to perform comprehensive enrichment analysis and repurpose new therapeutic options for HE. A total of 457 DEGs were identified in 2 data sets totally from 12 cirrhotic patients with HE compared with 12 healthy subjects. We found that 274 genes were upregulated and 183 genes were downregulated. Network analyses on significant DEGs indicated 12 hub genes associated with HE. Enrichment analysis identified fatty acid beta-oxidation, cerebral organic acidurias, and regulation of actin cytoskeleton as main involved pathways associated with upregulated genes; serotonin receptor 2 and ELK-SRF/GATA4 signaling, GPCRs, class A rhodopsin-like, and p38 MAPK signaling pathway were related to downregulated genes. Finally, we predicted 39 probable effective drugs/agents for HE. This study not only confirms main important involved mechanisms of HE but also reveals some yet unknown activated molecular and cellular pathways in human HE. In addition, new targets were identified that could be of value in the future study of HE.

Muscarinic Receptors Associated with Cancer

Simple Summary

Recently, cancer research has described the presence of the cholinergic machinery, specifically muscarinic receptors, in a wide variety of cancers due to their activation and signaling pathways associated with tumor progression and metastasis, providing a wide overview of their contribution to different cancer formation and development for new antitumor targets. This review focused on determining the molecular signatures associated with muscarinic receptors in breast and other cancers and the need for pharmacological, molecular, biochemical, technological, and clinical approaches to improve new therapeutic targets.

Abstract

Cancer has been considered the pathology of the century and factors such as the environment may play an important etiological role. The ability of muscarinic agonists to stimulate growth and muscarinic receptor antagonists to inhibit tumor growth has been demonstrated for breast, melanoma, lung, gastric, colon, pancreatic, ovarian, prostate, and brain cancer. This work aimed to study the correlation between epidermal growth factor receptors and cholinergic muscarinic receptors, the survival differences adjusted by the stage clinical factor, and the association between gene expression and immune infiltration level in breast, lung, stomach, colon, liver, prostate, and glioblastoma human cancers. Thus, targeting cholinergic muscarinic receptors appears to be an attractive therapeutic alternative due to the complex signaling pathways involved.

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

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Intestinal Clostridioides difficile Can Cause Liver Injury through the Occurrence of Inflammation and Damage to Hepatocytes

This study investigated if intestinal Clostridioides difficile (CD) causes liver injury. Four-week-old male C3H/HeN mice were treated with phosphate-buffered solution (control), CD, diethylnitrosamine (DEN) to induce liver injury with PBS (DEN+PBS), and DEN with CD (DEN+CD) for nine weeks. After sacrifice, livers and mesenteric lymph nodes (MLNs) were removed and bacterial translocation, transcriptomes, and proteins were analysed. CD was found in 20% of MLNs from the control and DEN+PBS groups, in 30% of MLNs from the CD group, and in 75% of MLNs from the DEN+CD groups, which had injured livers. Also, CD was detected in 50% of the livers in the DEN+CD group with CD-positive MLNs. Elevated IL-1β, HB-EGF, EGFR, TGF-α, PCNA, DES, HMGB1, and CRP expressions were observed in the CD and DEN+CD groups as compared to the control and DEN+PBS groups. Protein levels of IL-6 and HMGB1 were higher in the CD and DEN+CD groups than in the control and DEN+PBS groups. These results indicate that intestinal CD can initiate and aggravate liver injury, and the mechanism of pathogenesis for liver injury should be investigated in further studies.

EGF receptor inhibitors comprehensively suppress hepatitis B virus by downregulation of STAT3 phosphorylation

Current antiviral therapy can not cure chronic hepatitis B virus (HBV) infection or eliminate the risk of hepatocellular carcinoma. The licensed epidermal growth factor receptor (EGFR) inhibitors have found to inhibit hepatitis C virus replication via downregulation of signal transducers and activators of transcription 3 (STAT3) phosphorylation. Since STAT3 is also involved in HBV replication, we further studied the anti-HBV efficacy of the EGFR inhibitors in this study. HBV-transfected HepG2.2.15 cells and HBV-infected HepG2-NTCP cells were used as cell models, and HBV replication, the syntheses of viral antigens and the magnitude of the covalently closed circular DNA (cccDNA) reservoir were used as indictors to test the anti-HBV effects of EGFR inhibitors erlotinib and gefitinib. Erlotinib inhibited HBV replication with a half-maximal inhibitory concentration of 1.05 μM. It also reduced the syntheses of viral antigens at concentrations of 2.5 μM or higher. The underlying mechanism was possibly correlated with its inhibition on STAT3 phosphorylation via up-regulation of suppressor of cytokine signaling 3. Gefitinib also inhibited HBV replication and antigen syntheses. Compared with the commonest antiviral drug entecavir, these EGFR inhibitors additionally reduced hepatitis B e antigen and erlotinib also marginally affected the cccDNA reservoir in HBV-infected HepG2-NTCP cells. Interestingly, these promising anti-HBV effects were significantly enhanced by extension of treatment duration. In conclusion, EGFR inhibitors demonstrated a comprehensive anti-HBV potential, highlighting a new strategy to cure HBV infection and suggesting animal model-related studies or clinical try in the future.

Role of epidermal growth factor receptor in liver injury and lipid metabolism: Emerging new roles for an old receptor

Epidermal growth factor receptor (EGFR) is conventionally known to play a crucial role in hepatocyte proliferation, liver regeneration and is also associated with hepatocellular carcinogenesis. In addition to these proliferative roles, EGFR has also implicated in apoptotic cell death signaling in various hepatic cells, mitochondrial dysfunction and acute liver necrosis in a clinically relevant murine model of acetaminophen overdose, warranting further comprehensive exploration of this paradoxical role of EGFR in hepatotoxicity. Apart from ligand dependent activation, EGFR can also be activated in ligand-independent manner, which is mainly associated to liver injury. Recent evidence has also emerged demonstrating important role of EGFR in lipid and fatty acid metabolism in quiescent and regenerating liver. Based on these findings, EGFR has also been shown to play an important role in steatosis in clinically relevant murine NAFLD models via regulating master transcription factors governing fatty acid synthesis and lipolysis. Moreover, several lines of evidences indicate that EGFR is also involved in hepatocellular injury, oxidative stress, inflammation, direct stellate cell activation and fibrosis in chronic liver injury models, including repeated CCl₄ exposure, high-fat diet and fast-food diet models. In addition to briefly summarizing role of EGFR in liver regeneration, this review comprehensively discusses all these non-conventional emerging roles of EGFR. Considering evidences of multi-facet role of EGFR at various levels in these pathophysiological process, EGFR can be a promising therapeutic target for various liver diseases, including acute liver failure and NAFLD, requiring further exploration. These roles of EGFR are relevant for alcoholic liver diseases (ALD) as well, thus providing a valid rationale for future investigations exploring a role of EGFR in ALD.

EGF neutralization antibodies attenuate liver fibrosis by inhibiting myofibroblast proliferation in bile duct ligation mice

The expression of epidermal growth factor (EGF) is increased during liver fibrogenesis, and EGF receptor (EGFR) antagonist could attenuate liver fibrosis. Since EGFR is highly expressed by hepatocytes and cholangiocytes in cirrhotic liver, whether hepatic stellate cells express EGFR in response to EGF still needs exploration. Although EGFR antagonist could attenuate liver fibrosis, many ligands with EGF-like domains, besides EGF, can function through EGFR. Whether specifically blocking EGF could attenuate bile duct ligation (BDL)-induced liver fibrosis has not been revealed. BDL induced biliary infarcts and matrix deposition in mouse liver, and EGFR was expressed and phosphorylated by α-smooth muscle actin (αSMA)-positive myofibroblasts. LX-2 cells expressed EGFR, and these receptors were phosphorylated in the in vitro culture system. Growth curve and cell cycle analysis revealed that EGF could enhance cell proliferation of LX-2 cells. In addition, administration of EGF antibodies markedly reduced the EGF level in serum and the deposition of extracellular matrix in the liver of BDL mice when compared to IgG administration. Administration of EGF antibodies also reduced the phosphorylation of EGFR and the percentage of Ki-67-positive or PCNA-positive liver myofibroblasts of BDL mice when compared to IgG administration. Therefore, activated hepatic stellate cells express EGFR, thus being responsive to EGF signal, and administration of EGF antibodies could attenuate liver fibrosis by restricting the proliferation of myofibroblasts.

Rewiring Host Signaling: Hepatitis C Virus in Liver Pathogenesis

Hepatitis C virus (HCV) is a major cause of liver disease including metabolic disease, fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). HCV induces and promotes liver disease progression by perturbing a range of survival, proliferative, and metabolic pathways within the proinflammatory cellular microenvironment. The recent breakthrough in antiviral therapy using direct-acting antivirals (DAAs) can cure >90% of HCV patients. However, viral cure cannot fully eliminate the HCC risk, especially in patients with advanced liver disease or comorbidities. HCV induces an epigenetic viral footprint that promotes a pro-oncogenic hepatic signature, which persists after DAA cure. In this review, we summarize the main signaling pathways deregulated by HCV infection, with potential impact on liver pathogenesis. HCV-induced persistent signaling patterns may serve as biomarkers for the stratification of HCV-cured patients at high risk of developing HCC. Moreover, these signaling pathways are potential targets for novel chemopreventive strategies.

Animal Models of Hepatocellular Carcinoma Prevention

Hepatocellular carcinoma (HCC) is a deadly disease and therapeutic efficacy in advanced HCC is limited. Since progression of chronic liver disease to HCC involves a long latency period of a few decades, a significant window of therapeutic opportunities exists for prevention of HCC and improve patient prognosis. Nonetheless, there has been no clinical advancement in instituting HCC chemopreventive strategies. Some of the major challenges are heterogenous genetic aberrations of HCC, significant modulation of tumor microenvironment and incomplete understanding of HCC tumorigenesis. To this end, animal models of HCC are valuable tools to evaluate biology of tumor initiation and progression with specific insight into molecular and genetic mechanisms involved. In this review, we describe various animal models of HCC that facilitate effective ways to study therapeutic prevention strategies that have translational potential to be evaluated in a clinical context.

Immunohistochemical Expression of Epidermal Growth Factor Receptor in Hepatocellular Carcinoma

INTRODUCTION

Epidermal growth factor receptor (EGFR) signaling plays an important role in various cancers, including hepatocellular carcinoma (HCC). We aimed to evaluate immunoexpression of EGFR in HCC and surrounding non-tumor liver tissue and to correlate it to multiple clinicopathologic data.

MATERIAL AND METHODS

We analyzed 60 patients with HCC for multiple clinicopathologic characteristics and survival. Presence of the immunosignal and the percentage of positive tumor cells at the whole tumor tissue sample and adjacent cirrhotic liver tissue were semi-quantitatively determined.

RESULTS

Nineteen patients (31.67%) were female and 41 (68.33%) were male ranging in age from 31 to 85 years, median 61.88±10.51. Mean survival time for female patients was 8.86±1.76 months, for male 13.03±1.50 months and overall survival was 11.6051±1.19 months. The most patients had: T2 status (41.67%), no enlarged lymph nodes (90%), vascular invasion (63.33%) and well differentiated (43.33%) tumors. EGFR immunoexpression was determined in range from 0% to 100% in both tumor and non-tumor tissue with mean value of 39.58% in tumor and 86.86% in cirrhotic tissue (p<0.00). Higher percent of tumor EGFR positive cells were found in cases with higher T status, higher levels of AFP and poorly differentiated carcinoma, but not significantly. Lower percent of tumor EGFR positive cells were found in patients with vascular invasion and enlarged lymph nodes, but also not significantly. EGFR expression in tumor tissue significantly influenced survival of the patients (p<0.05).

CONCLUSION

The study showed that expression of EGFR in lower percentage of tumor cells was associated to favorable prognosis, making it a potential prognostic marker and therapeutic target.

Proteomic profiling of HBV infected liver biopsies with different fibrotic stages

Background

Hepatitis B virus (HBV) is a global health problem, and infected patients if left untreated may develop cirrhosis and eventually hepatocellular carcinoma. This study aims to enlighten pathways associated with HBV related liver fibrosis for delineation of potential new therapeutic targets and biomarkers.

Methods

Tissue samples from 47 HBV infected patients with different fibrotic stages (F1 to F6) were enrolled for 2D-DIGE proteomic screening. Differentially expressed proteins were identified by mass spectrometry and verified by western blotting. Functional proteomic associations were analyzed by EnrichNet application.

Results

Fibrotic stage variations were observed for apolipoprotein A1 (APOA1), pyruvate kinase PKM (KPYM), glyceraldehyde 3-phospahate dehydrogenase (GAPDH), glutamate dehydrogenase (DHE3), aldehyde dehydrogenase (ALDH2), alcohol dehydrogenase (ALDH1A1), transferrin (TRFE), peroxiredoxin 3 (PRDX3), phenazine biosynthesis-like domain-containing protein (PBLD), immuglobulin kappa chain C region (IGKC), annexin A4 (ANXA4), keratin 5 (KRT5). Enrichment analysis with Reactome and Kegg databases highlighted the possible involvement of platelet release, glycolysis and HDL mediated lipid transport pathways. Moreover, string analysis revealed that HIF-1α (Hypoxia-inducible factor 1-alpha), one of the interacting partners of HBx (Hepatitis B X protein), may play a role in the altered glycolytic response and oxidative stress observed in liver fibrosis.

Conclusions

To our knowledge, this is the first protomic research that studies HBV infected fibrotic human liver tissues to investigate alterations in protein levels and affected pathways among different fibrotic stages. Observed changes in the glycolytic pathway caused by HBx presence and therefore its interactions with HIF-1α can be a target pathway for novel therapeutic purposes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12953-017-0114-4) contains supplementary material, which is available to authorized users.

Epidermal Growth Factor Receptor (EGF-R) in Dupuytren’s Disease

The aim of this paper was to examine participation of the epidermal growth factor receptor (EGF-R) signal pathway in the pathogenesis of Dupuytren’s disease. The study showed changes in the ratio of membrane EGF-R to its intracellular level during the different clinical stages of Dupuytren’s contracture progression. Our observations of a high ratio of surface to intracellular EGF-R in the palmar aponeurosis of patients with second degree of Dupuytren’s disease (Iselin’s classification), which was significantly higher than this ratio in control palmar fascia ( P = 0.022), would suggest that EGF-R has a role in the involutional phase of the disease.

EGFR Signaling in Liver Diseases

The epidermal growth factor receptor (EGFR) is a transmembrane receptor tyrosine kinase that is activated by several ligands leading to the activation of diverse signaling pathways controlling mainly proliferation, differentiation, and survival. The EGFR signaling axis has been shown to play a key role during liver regeneration following acute and chronic liver damage, as well as in cirrhosis and hepatocellular carcinoma (HCC) highlighting the importance of the EGFR in the development of liver diseases. Despite the frequent overexpression of EGFR in human HCC, clinical studies with EGFR inhibitors have so far shown only modest results. Interestingly, a recent study has shown that in human HCC and in mouse HCC models the EGFR is upregulated in liver macrophages where it plays a tumor-promoting function. Thus, the role of EGFR in liver diseases appears to be more complex than what anticipated. Further studies are needed to improve the molecular understanding of the cell-specific signaling pathways that control disease development and progression to be able to develop better therapies targeting major components of the EGFR signaling network in selected cell types. In this review, we compiled the current knowledge of EGFR signaling in different models of liver damage and diseases, mainly derived from the analysis of HCC cell lines and genetically engineered mouse models (GEMMs).

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

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

In vitro reversion of activated primary human hepatic stellate cells

Background

Liver fibrosis is characterized by the excessive formation and accumulation of matrix proteins as a result of wound healing in the liver. A main event during fibrogenesis is the activation of the liver resident quiescent hepatic stellate cell (qHSC). Recent studies suggest that reversion of the activated HSC (aHSC) phenotype into a quiescent-like phenotype could be a major cellular mechanism underlying fibrosis regression in the liver, thereby offering new therapeutic perspectives for the treatment of liver fibrosis. Whether human HSCs have the ability to undergo a similar reversion in phenotype is currently unknown. The aim of the present study is to identify experimental conditions that can revert the in vitro activated phenotype of primary human HSCs and consequently to map the molecular events associated with this reversion process by gene expression profiling.

Results

We find that epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2) synergistically downregulate the expression of ACTA2 and LOX in primary human aHSCs. Their combination with oleic acid, palmitic acid, and retinol further potentiates a more quiescent-like phenotype as demonstrated by the abundant presence of retinyl ester-positive intra-cytoplasmic lipid droplets, low expression levels of activation markers, and a reduced basal as well as cytokine-stimulated proliferation and matrix metalloproteinase activity. Gene expression profiling experiments reveal that these in vitro reverted primary human HSCs (rHSCs) display an intermediary phenotype that is distinct from qHSCs and aHSCs. Interestingly, this intermediary phenotype is characterized by the increased expression of several previously identified signature genes of in vivo inactivated mouse HSCs such as CXCL1, CXCL2, and CTSS, suggesting also a potential role for these genes in promoting a quiescent-like phenotype in human HSCs.

Conclusions

We provide evidence for the ability of human primary aHSCs to revert in vitro to a transitional state through synergistic action of EGF, FGF2, dietary fatty acids and retinol, and provide a first phenotypic and genomic characterization of human in vitro rHSCs.

Electronic supplementary material

The online version of this article (doi:10.1186/s13069-015-0031-z) contains supplementary material, which is available to authorized users.

EGF/EGFR axis contributes to the progression of cholangiocarcinoma through the induction of an epithelial-mesenchymal transition

BACKGROUND & AIMS

Epithelial-mesenchymal transition (EMT) is a cellular process involved in cancer progression. The first step of EMT consists in the disruption of E-cadherin-mediated adherens junctions. Cholangiocarcinoma (CCA), a cancer with a poor prognosis due to local invasion and metastasis, displays EMT features. EGFR, a receptor tyrosine kinase, plays a major role in CCA progression. The aim of the study was to determine if EMT is induced by EGFR in CCA cells.

METHODS

In vivo, the expression of E-cadherin was analysed in CCA tumours of 100 patients and correlated with pathological features and EGFR expression, and in a xenograft model in mice treated with gefitinib, an inhibitor of EGFR. In vitro, the regulation of EMT by EGFR was investigated in CCA cell lines.

RESULTS

In human CCA, a cytoplasmic localization of E-cadherin occurred in 50% of the tumours was associated with the peripheral type of CCA, tumour size, the presence of satellite nodules and EGFR overexpression. In xenografted tumours, E-cadherin displayed a cytoplasmic pattern whereas the treatment of mice with gefitinib restored the membranous expression of E-cadherin. In vitro, EGF induced scattering of CCA cells that resulted from the disruption of adherens junctions. Internalization and decreased expression of E-cadherin, as well as nuclear translocation of β-catenin, were observed in EGF-treated CCA cells. In these cells, EMT-transcription factors (i.e., Slug and Zeb-1) and mesenchymal markers (i.e., N-cadherin and α-SMA) were induced, favoring cell invasiveness through cytoskeleton remodeling. All these effects were inhibited by gefitinib.

CONCLUSIONS

The EGF/EGFR axis triggers EMT in CCA cells highlighting the key role of this pathway in CCA progression.

Alcohol Disrupts Human Liver Stem/Progenitor Cell Proliferation and Differentiation

OBJECTIVE

Excessive alcohol consumption injures the liver resulting in various liver diseases including liver cirrhosis. Advanced liver disease continues to be a major challenge to human health. Liver stem/progenitor cells (LSPCs) are tissue specific precursors with a distinct capacity of multi-lineage differentiation. These precursor cells may play an important role in the process of tissue injury repair and pathological transition of liver structures. At the present time, knowledge about the effect of alcohol on LSPC function during the development of alcoholic liver disease remains absent. This study was conducted to investigate changes in LSPC activity of proliferation and differentiation following alcohol exposure. The disruption of cell signaling mechanisms underlying alcohol-induced alteration of LSPC activities was also examined.

METHODS

Primary and immortalized human liver stem cells (HL1-1 cells and HL1-hT1 cells, respectively) were cultured in media optimized for cell proliferation and hepatocyte differentiation in the absence and presence of ethanol. Changes in cell morphology, proliferation and differentiation were determined. Functional disruption of cell signaling components following alcohol exposure was examined.

RESULTS

Ethanol exposure suppressed HL1-1 cell growth [as measured by cell 5-bromo-2-deoxyuridine (BrdU) incorporation] mediated by epidermal growth factor (EGF) or EGF plus interleukin-6 (IL-6) in an ethanol dose-dependent manner. Similarly, ethanol inhibited BrdU incorporation into HL1-hT1 cells. Cyclin D1 mRNA expression by HL1-hT1 cells was suppressed when cells were cultured with 50 and 100 mM ethanol. Ethanol exposure induced morphological change of HL1-1 cells toward a myofibroblast-like phenotype. Furthermore, ethanol down-regulated E-cadherin expression while increasing collagen I expression by HL1-1 cells. Ethanol also stimulated Snail transcriptional repressor (Snail) and α-smooth muscle actin (α-SMA) gene expression by HL1-1 cells.

CONCLUSION

These results demonstrate that the direct effect of alcohol on LSPCs is inhibiting their proliferation and promoting mesenchymal transition during their differentiation. Alcohol interrupts LSPC differentiation through interfering Snail signaling.

Epidermal growth factor receptor inhibition attenuates liver fibrosis and development of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most rapidly increasing cause of cancer-related mortality in the United States. Because of the lack of viable treatment options for HCC, prevention in high-risk patients has been proposed as an alternative strategy. The main risk factor for HCC is cirrhosis and several lines of evidence implicate epidermal growth factor (EGF) in the progression of cirrhosis and development of HCC. We therefore examined the effects of the EGF receptor (EGFR) inhibitor erlotinib on liver fibrogenesis and hepatocellular transformation in three different animal models of progressive cirrhosis: a rat model induced by repeated, low-dose injections of diethylnitrosamine (DEN), a mouse model induced by carbon tetrachloride (CCl4 ), and a rat model induced by bile duct ligation (BDL). Erlotinib reduced EGFR phosphorylation in hepatic stellate cells (HSC) and reduced the total number of activated HSC. Erlotinib also decreased hepatocyte proliferation and liver injury. Consistent with all these findings, pharmacological inhibition of EGFR signaling effectively prevented the progression of cirrhosis and regressed fibrosis in some animals. Moreover, by alleviating the underlying liver disease, erlotinib blocked the development of HCC and its therapeutic efficacy could be monitored with a previously reported gene expression signature predictive of HCC risk in human cirrhosis patients.

CONCLUSION

These data suggest that EGFR inhibition using Food and Drug Administration-approved inhibitors provides a promising therapeutic approach for reduction of fibrogenesis and prevention of HCC in high-risk cirrhosis patients who can be identified and monitored by gene expression signatures.

The EGFR signalling system in the liver: from hepatoprotection to hepatocarcinogenesis

The liver displays an outstanding wound healing and regenerative capacity unmatched by any other organ. This reparative response is governed by a complex network of inflammatory mediators, growth factors and metabolites that are set in motion in response to hepatocellular injury. However, when liver injury is chronic, these regenerative mechanisms become dysregulated, facilitating the accumulation of genetic alterations leading to unrestrained cell proliferation and the development of hepatocellular carcinoma (HCC). The epidermal growth factor receptor (EGFR or ErbB1) signaling system has been identified as a key player in all stages of the liver response to injury, from early inflammation and hepatocellular proliferation to fibrogenesis and neoplastic transformation. The EGFR system engages in extensive crosstalk with other signaling pathways, acting as a true signaling hub for other growth factors, cytokines and inflammatory mediators. Here, we briefly review essential aspects of the biology of the EGFR, the other ErbB receptors, and their ligands in liver injury, regeneration and HCC development. Some aspects of the preclinical and clinical experience with EGFR therapeutic targeting in HCC are also discussed.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Epidermal growth factor, its receptor and transforming growth factor-β1 in the diagnosis of HCV-induced hepatocellular carcinoma

In this article, we present a study on the levels of epidermal growth factor (EGF), its phosphorylated receptor (p-EGFR) and transforming growth factor-β1 (TGF-β1) in the sera of patients with hepatocellular carcinoma (HCC) and chronic hepatitis C (CHC) infection. The results reveal significant higher serum levels of EGF and TGF-β1 in patients with HCC compared to their level in patients with CHC infection and control subjects. The levels of p-EGFR in HCC and CHC patients show a highly significant difference between patients. Based on the best cutoff value of 914 pg/ml, EGF shows 63.3 % sensitivity and 87.5 % specificity for HCC patients where the area under the curve is 0.81. The p-EGFR shows sensitivity of 63.3 % and specificity of 100 % where the area under the curve is 0.87 for HCC patients based on the best cutoff value of 39 U/mg protein. The best cutoff value (370 pg/ml) for serum TGF-β1 displays sensitivity of 86.7 % and specificity of 100 %, where the area under the curve is 0.97 for HCC patients.

Novel human monoclonal antibody against epidermal growth factor receptor as an imaging probe for hepatocellular carcinoma

OBJECTIVE

The epidermal growth factor receptor (EGFR) is overexpressed in many epithelial cancers, including hepatocellular carcinoma (HCC), and is an attractive target for cancer imaging and therapy. We attempted a novel noninvasive imaging method to evaluate anti-EGFR human monoclonal antibody clones for determining the uptake of therapeutic anti-EGFR antibody in HCC.

METHODS

In-vitro cell binding of nine I-labeled antibody clones was compared in the human epidermoid cancer cell line A431, in three HCC cell lines Hep-G2, SK-Hep1, and HuH-7, and in the EGFR-negative control cell line A4. In-labeled or I-labeled 048-006 was subjected to cell binding, competitive inhibition, and internalization assays using A431, SK-Hep1, and HuH-7. Further, In-labeled 048-006 was evaluated in in-vivo biodistribution analysis and single-photon imaging in nude tumor-bearing mice.

RESULTS

The 048-006 clone showed the highest binding to EGFR-expressing cells among the nine antibodies. In-labeled or I-labeled 048-006 specifically bound to EGFR-expressing cells with high affinity and was internalized after binding to EGFR. A431 and HuH-7 tumors showed high In-labeled 048-006 uptake, which was visualized by single-photon imaging.

CONCLUSION

Radiolabeled human anti-EGFR monoclonal antibody 048-006 has the potential to be a safer imaging probe for predicting tumor uptake of anti-EGFR antibody therapeutic agents in HCC.

Epidermal growth factor gene polymorphism 61A/G in patients with chronic liver disease for early detection of hepatocellular carcinoma: a pilot study

BACKGROUND

Overexpression of epidermal growth factor (EGF) in the liver induces transformation into hepatocellular carcinoma (HCC) in animal models. Polymorphisms in the EGF gene modulate EGF levels.

OBJECTIVES

To evaluate the effect of EGF gene single nucleotide polymorphism and to assess its correlation with the risk of HCC in patients with chronic liver diseases.

PATIENTS AND METHODS

The present study included 80 participants divided into four groups: group 1 included 20 asymptomatic healthy control volunteers, group 2 included 20 patients with chronic hepatitis C viral (HCV) infection, group 3 included 20 patients with liver cirrhosis, and group 4 included 20 patients with HCC. For all participants, the following investigations were performed: routine laboratory investigations including complete blood count, liver function tests, sero markers of hepatitis viruses HBsAg, HCV-RNA by quantitative polymerase chain reaction, and α-fetoprotein. DNA was extracted from whole blood for detection of single nucleotide polymorphism of the EGF by polymerase chain reaction, followed by restriction fragment length polymorphism.

RESULTS

We found a significant difference between both patients with HCC and HCV versus controls in terms of the G carrier (GG and GA; 80 vs. 40%, P<0.05). In addition, the cirrhotic and chronic hepatitis C patients with GG had three-fold and 2.3-fold odds ratio for developing HCC, respectively.

CONCLUSION

The EGF 61GG genotype might be associated with a high risk for the development of HCC in Egyptian patients with chronic liver disease.

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

BACKGROUND

Hepatocarcinogenesis is a complex process that may be influenced by many factors, including polymorphism in the epidermal growth factor (EGF) gene. Previous work suggests an association between the EGF 61*A/G polymorphism (rs4444903) and susceptibility to hepatocellular carcinoma (HCC), but the results have been inconsistent. Therefore, we performed a meta-analysis of several studies covering a large population to address this controversy.

METHODS

PubMed, EMBASE, Google Scholar and the Chinese National Knowledge Infrastructure databases were systematically searched to identify relevant studies. Data were abstracted independently by two reviewers. A meta-analysis was performed to examine the association between EGF 61*A/G polymorphism and susceptibility to HCC. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

Eight studies were chosen in this meta-analysis, involving 1,304 HCC cases (1135 Chinese, 44 Caucasian and 125 mixed) and 2,613 controls (1638 Chinese, 77 Caucasian and 898 mixed). The EGF 61*G allele was significantly associated with increased risk of HCC based on allelic contrast (OR = 1.29, 95% CI = 1.16-1.44, p<0.001), homozygote comparison (OR = 1.79, 95% CI = 1.39-2.29, p<0.001) and a recessive genetic model (OR = 1.34, 95% CI = 1.16-1.54, p<0.001), while patients carrying the EGF 61*A/A genotype had significantly lower risk of HCC than those with the G/A or G/G genotype (A/A vs. G/A+G/G, OR = 0.66, 95% CI = 0.53-0.83, p<0.001).

CONCLUSION

The 61*G polymorphism in EGF is a risk factor for hepatocarcinogenesis while the EGF 61*A allele is a protective factor. Further large and well-designed studies are needed to confirm this conclusion.

Carriage of the EGF rs4444903 A>G functional polymorphism associates with disease progression in chronic HBV infection

Because epidermal growth factor (EGF) up-regulation is characteristic of the cirrhotic liver, we hypothesised that the EGF rs4444903 A > G functional polymorphism might be associated with a worse disease course in patients with chronic HBV infection. To verify this hypothesis, 170 HBV-positive patients (125 males) with a median age of 52 years were studied. Sixty-two of these patients were followed longitudinally for a median time of 21 years. Genotyping for the EGF rs4444903 A > G polymorphism was performed by the polymerase chain reaction-based restriction fragment length polymorphism assay. In the cross-sectional study, the EGF rs4444903 A > G polymorphism genotypic frequencies significantly differed between transplant patients (A/A = 20·4%, A/G = 52·3%, G/G = 27·3%) and HBsAg+ carriers (active and inactive: A/A = 35·7%, A/G = 47·6%, G/G = 16·7%, P = 0·036 for the linear trend). In the longitudinal study, the EGF rs4444903 A > G polymorphism was found to be an independent predictor of cirrhosis development (O.R. 7·73, 95% C.I. 1·21-49·5, P = 0·007). Three groups of patients were identified: A/A female homozygotes (n = 9), A/A male homozygotes (n = 13) and carriers of the G allele of either gender (n = 40). Cirrhosis did not occur among A/A females (n = 0/9), seldom occurred among A/A males (n = 2/13) and reached the highest frequency among G/* patients (n = 13/40, P = 0·026). In conclusion, the EGF rs4444903 A > G polymorphism appears to be associated with an unfavourable disease course of chronic HBV infection and cirrhosis development. This effect might be modulated, at least in part, by the gender of the patient.

Concurrent inhibition of TGF-β and mitogen driven signaling cascades in Dupuytren's disease - non-surgical treatment strategies from a signaling point of view

Dupuytren's disease (DD) is a benign progressive fibro-proliferative disorder of the fascia palmaris of the hand. Currently, treatment consists of surgical excision with a relatively high recurrence rate and risk of complications. To improve long-term outcome of DD treatment, research focus has shifted towards molecular targets for DD as an alternative to surgery. Therefore, complete and exact understanding of the cause of DD is needed. Transforming growth factor (TGF)-β is considered a key player in DD. We recently showed that increased TGF-β expression in DD correlates not only with elevated expression and activation of downstream Smad effectors, but also with overactive ERK1/2 MAP kinase signaling. Both TGF-β/Smad and non-Smad signaling pathways increase expression of key fibrotic markers and contractility of Dupuytren's myofibroblasts. What is not yet known is whether these two signaling cascades each accelerate DD autonomously, successively or in conjunction. Elucidation of this mechanism will help develop new potential non-surgical treatments. We hypothesize that TGF-β-induced short-term activation of the MAPK pathway leads to an autonomous non-Smad driven fibrosis. Therefore, successful treatment strategies will target not only TGF-β/Smad, but also intracellular MAPK signaling. In this review we discuss possible scenarios in which such a drift from TGF-β induced Smad signaling to autonomous non-Smad signaling could be observed in DD. The potential therapeutic effects of small cytokine signaling cascades inhibitors, such as TGF-β type I receptor-, (pan-) tyrosine- or ERK1/2 MAP-kinase inhibitor will be highlighted. To abrogate the fibrotic trait and the recurrence of DD, we speculate on sequential and co-application of such molecules in order to provide possible new non-operative strategies for DD.

Association between the epidermal growth factor rs4444903 G/G genotype and advanced fibrosis at a young age in chronic hepatitis C

BACKGROUND

The epidermal growth factor (EGF) rs4444903 A>G polymorphism has been associated with the development of liver cancer, which commonly complicates cirrhosis of viral origin; however, whether this polymorphism might be associated with fibrosis progression in chronic viral hepatitis is unknown. The present study was performed to assess the allelic and genotypic frequencies of the rs4444903 A>G polymorphism in patients with chronic hepatitis C virus HCV infection and to ascertain whether this polymorphism might be an independent predictor of the degree of fibrosis.

METHODS

An RFLP-PCR technique was used to genotype 645 patients (211 with cirrhosis); 528 were referred for the diagnosis and treatment of chronic hepatitis C, and 117 were transplanted for HCV-related end stage liver disease. A group of 428 healthy subjects served as a control. All the subjects were of Caucasian ethnicity.

RESULTS

The EGF rs4444903 A>G polymorphism genotype frequencies in HCV chronic infected patients were as follows: A/A=227 (35.3%), A/G=328 (50.9%), and G/G=90 (14.8%). Genotype frequencies were found to differ between patients with an Ishak staging score⩽2 (A/A=117, A/G=157, G/G=34) and patients with a score>2 (A/A=110, A/G=171, G/G=56, p=0.038). A highly significant linear relationship between increasing stage scores and EGF genotype was detected in younger patients (A/A: 2.02±0.18, A/G: 2.55±0.17, G/G: 3.00±0.32, p=0.008). However, no significant association was detected between the stage score and EGF genotype in older patients (A/A: 3.79±0.19, A/G: 3.64±0.15, G/G: 3.98±0.30 p=0.579).

CONCLUSIONS

The EGF rs4444903 A>G polymorphism may facilitate liver fibrosis progression in Caucasian patients with chronic hepatitis C, especially in younger patients.

A functional polymorphism in the epidermal growth factor gene is associated with risk for hepatocellular carcinoma

BACKGROUND & AIMS

A single nucleotide polymorphism 61*G (rs4444903) in the epidermal growth factor (EGF) gene has been associated, in 2 case-control studies, with hepatocellular carcinoma (HCC). We tested associations between demographic, clinical, and genetic data and development of HCC, and developed a simple predictive model in a cohort of patients with chronic hepatitis C and advanced fibrosis.

METHODS

Black and white subjects from the Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) trial (n=816) were followed up prospectively for development of a definite or presumed case of HCC for a median time period of 6.1 years. We used the Cox proportional hazards regression model to determine the hazard ratio for risk of HCC and to develop prediction models.

RESULTS

Subjects with EGF genotype G/G had a higher adjusted risk for HCC than those with genotype A/A (hazard ratio, 2.10; 95% confidence interval, 1.05-4.23; P=.03). After adjusting for EGF genotype, blacks had no increased risk of HCC risk compared with whites. Higher serum levels of EGF were observed among subjects with at least one G allele (P=.08); the subset of subjects with EGF G/G genotype and above-median serum levels of EGF had the highest risk of HCC. We developed a simple prediction model that included the EGF genotype to identify patients at low, intermediate, and high risk for HCC; 6-year cumulative HCC incidences were 2.3%, 10.4%, and 26%, respectively.

CONCLUSIONS

We associated the EGF genotype G/G with increased risk for HCC; differences in its frequency among black and white subjects might account for differences in HCC incidence between these groups. We developed a model that incorporates EGF genotype and demographic and clinical variables to identify patients at low, intermediate, and high risk for HCC.

Preclinical evaluation of (177)lu-nimotuzumab: a potential tool for radioimmunotherapy of epidermal growth factor receptor-overexpressing tumors

BACKGROUND

The humanized monoclonal antibody Nimotuzumab (h-R3) has demonstrated an exceptional and better clinical profile than other monoclonal antibodies for immunotherapy of epidermal growth factor receptor-overexpressing tumors. This work deals with the preparation and radiolabeling optimization of (177)Lu-Nimotuzumab and their preclinical evaluation.

METHODS

Nimotuzumab was conjugated with S-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane tetraacetic acid (p-SCN-Bn-DOTA), testing different molar ratios. The immunoconjugates were characterized. The radiolabeling with (177)Lu was optimized. Radioimmunoconjugates stability was tested in 2-[bis[2-[bis(carboxymethyl)amino]ethyl]amino]acetic acid (DTPA) excess and human serum. In vitro studies were performed in tumor model cell lines. Receptor-specific binding was tested by competitive inhibition. (177)Lu-Nimotuzumab in vivo studies were conducted in healthy and xenograft animals.

RESULTS

Nimotuzumab conjugates were obtained with high purity. Radiolabeling yield and specific activities ranged from 63.6% to 94.5% and from 748 to 1142 MBq/mg, respectively. The stability in DTPA excess and human serum was 95.9% and 93.2% after 10 days, respectively. The radioimmunoconjugate showed specific receptor binding in tumor cell lines. Biodistribution in healthy animals showed the typical behavior of the immunoconjugates based on monoclonal antibodies. The study in xenografts mice demonstrated uptake of (177)Lu-Nimotuzumab in the tumor and reticuloendothelial organs.

CONCLUSIONS

(177)Lu-Nimotuzumab was obtained with high purity and specific activities under optimal conditions without significant loss in immunoreactivity and might be a potential radioimmunoconjugate for radioimmunotherapy of tumors with epidermal growth factor receptor overexpression.

Role of lipid rafts in liver health and disease

Liver diseases are an increasingly common cause of morbidity and mortality; new approaches for investigation of mechanisms of liver diseases and identification of therapeutic targets are emergent. Lipid rafts (LRs) are specialized domains of cellular membranes that are enriched in saturated lipids; they are small, mobile, and are key components of cellular architecture, protein partition to cellular membranes, and signaling events. LRs have been identified in the membranes of all liver cells, parenchymal and non-parenchymal; more importantly, LRs are active participants in multiple physiological and pathological conditions in individual types of liver cells. This article aims to review experimental-based evidence with regard to LRs in the liver, from the perspective of the liver as a whole organ composed of a multitude of cell types. We have gathered up-to-date information related to the role of LRs in individual types of liver cells, in liver health and diseases, and identified the possibilities of LR-dependent therapeutic targets in liver diseases.

A novel role of dipeptidyl peptidase 9 in epidermal growth factor signaling

Dipeptidyl peptidase IV (DPP4), DPP8, DPP9, and fibroblast activation protein (FAP), the four proteases of the DPP4 gene family, have unique peptidase and extra-enzymatic activities that have been implicated in various diseases including cancers. We report here a novel role of DPP9 in regulating cell survival and proliferation through modulating molecular signaling cascades. Akt (protein kinase B) activation was significantly inhibited by human DPP9 overexpression in human hepatoma cells (HepG2 and Huh7) and human embryonic kidney cells (HEK293T), whereas extracellular signal-regulated kinases (ERK1/2) activity was unaffected, revealing a pathway-specific effect. Interestingly, the inhibitory effect of DPP9 on Akt pathway activation was growth factor dependent. DPP9 overexpression caused apoptosis and significantly less epidermal growth factor (EGF)-mediated Akt activation in HepG2 cells. However, such inhibitory effect was not observed in cells stimulated with other growth factors, including connective tissue growth factor, hepatic growth factor, insulin or platelet-derived growth factor-BB. The effect of DPP9 on Akt did not occur when DPP9 enzyme activity was ablated by either mutagenesis or inhibition. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway is a major downstream effector of Ras. We found that DPP9 and DPP8, but not DPP4 or FAP, associate with H-Ras, a key signal molecule of the EGF receptor signaling pathway. These findings suggest an important signaling role of DPP9 in the regulation of survival and proliferation pathways.

Clinical Benefits of Biochemical Markers of Fibrosis in Egyptian Children With Chronic Liver Diseases

BACKGROUND

The need for repetition of liver biopsy, especially in assessing the degree of fibrosis and follow-up of treatment protocols, justifies an intensive search for non-invasive alternatives. We attempted to investigate the clinical usefulness of serum fibrogenesis markers in pediatric chronic liver diseases.

METHODS

We measured serum levels of TGF-β1, collagen IV, laminin, MMP-2 and EGF-R, in 50 children with chronic liver disease (HBV, HCV and Bilharziasis) and 30 healthy controls, and determined their relationship to frequently used liver function tests and liver biopsy findings in patients.

RESULTS

TGF-β1, collagen IV, laminin and MMP-2, but not EGF-R, were significantly higher in patients than in controls (P < 0.01). None of these markers correlated with the histological fibrosis stage, whereas laminin correlated with necroinflammatory activity (P < 0.01). TGF-β1, collagen IV, laminin and MMP-2 had the ability to discriminate patients with significant fibrosis, while only collagen IV and laminin were able to discriminate those with cirrhosis. Among these markers, collagen IV had the best predictive accuracy for significant fibrosis (AUROC 0.94; PPV 91.5%) and cirrhosis (AUROC 0.85; PPV 80%).

CONCLUSIONS

In conclusion, these markers may be useful in reducing but not replacing the need for liver biopsy in the monitoring of disease progression and treatment effectiveness and might be an inseparable part of assessment of chronic hepatopathies.

Mouse model of carbon tetrachloride induced liver fibrosis: Histopathological changes and expression of CD133 and epidermal growth factor

BACKGROUND

In the setting of chronic liver injury in humans, epidermal growth factor (EGF) and EGF receptor (EGFR) are up-regulated and have been proposed to have vital roles in both liver regeneration and development of hepatocellular carcinoma (HCC). Chronic liver injury also leads to hepatic stellate cell (HSC) differentiation and a novel subpopulation of HSCs which express CD133 and exhibit properties of progenitor cells has been described in rats. The carbon tetrachloride (CCl4)-induced mouse model has been historically relied upon to study liver injury and regeneration. We exposed mice to CCl4 to assess whether EGF and CD133+ HSCs are up-regulated in chronically injured liver.

METHODS

CCl4 in olive oil was administered to strain A/J mice three times per week by oral gavage.

RESULTS

Multiple well-differentiated HCCs were found in all livers after 15 weeks of CCl4 treatment. Notably, HCCs developed within the setting of fibrosis and not cirrhosis. CD133 was dramatically up-regulated after CCl4 treatment, and increased expression of desmin and glial fibrillary acidic protein, representative markers of HSCs, was also observed. EGF expression significantly decreased, contrary to observations in humans, whereas the expression of amphiregulin, another EGFR ligand, was significantly increased.

CONCLUSIONS

Species-specific differences exist with respect to the histopathological and molecular pathogenesis of chronic liver disease. CCl4-induced chronic liver injury in A/J mice has important differences compared to human cirrhosis leading to HCC.

In vivo imaging of xenograft tumors using an epidermal growth factor receptor-specific affibody molecule labeled with a near-infrared fluorophore

Overexpression of epidermal growth factor receptor (EGFR) is associated with many types of cancers. It is of great interest to noninvasively image the EGFR expression in vivo. In this study, we labeled an EGFR-specific Affibody molecule (Eaff) with a near-infrared (NIR) dye IRDye800CW maleimide and tested the binding of this labeled molecule (Eaff800) in cell culture and xenograft mouse tumor models. Unlike EGF, Eaff did not activate the EGFR signaling pathway. Results showed that Eaff800 was bound and taken up specifically by EGFR-overexpressing A431 cells. When Eaff800 was intravenously injected into nude mice bearing A431 xenograft tumors, the tumor could be identified 1 hour after injection and it became most prominent after 1 day. Images of dissected tissue sections demonstrated that the accumulation of Eaff800 was highest in the liver, followed by the tumor and kidney. Moreover, in combination with a human EGFR type 2 (HER2)-specific probe Haff682, Eaff800 could be used to distinguish between EGFR- and HER2-overexpressing tumors. Interestingly, the organ distribution pattern and the clearance rate of Eaff800 were different from those of Haff682. In conclusion, Eaff molecule labeled with a NIR fluorophore is a promising molecular imaging agent for EGFR-overexpressing tumors.

Activation of peroxisome proliferator-activated receptor-gamma by curcumin blocks the signaling pathways for PDGF and EGF in hepatic stellate cells

During hepatic fibrogenesis, reduction in the abundance of peroxisome proliferator-activated receptor-gamma (PPARgamma) is accompanied by activation of mitogenic signaling for platelet-derived growth factor (PDGF) and epidermal growth factor (EGF) in hepatic stellate cells (HSCs), the major effector cells. We previously reported that curcumin, the yellow pigment in curry, interrupted PDGF and EGF signaling, stimulated PPARgamma gene expression, and enhanced its activity, leading to inhibition of cell proliferation of activated HSC in vitro and in vivo. The aim of this study was to elucidate the underlying mechanisms. We hypothesized that the enhancement of PPARgamma activity by curcumin might result in the interruption of PDGF and EGF signaling. Our experiments demonstrated that curcumin, with different treatment strategies, showed different efficiencies in the inhibition of PDGF- or EGF-stimulated HSC proliferation. Further experiments observed that curcumin dose dependently reduced gene expression of PDGF and EGF receptors (ie, PDGF-betaR and EGFR), which required PPARgamma activation. The activation of PPARgamma by its agonist suppressed pdgf-betar and egfr expression in HSC. In addition, curcumin reduced the phosphorylation levels of PDGF-betaR and EGFR, as well as their downstream signaling cascades, including ERK1/2 and JNK1/2. Moreover, activation of PPARgamma induced gene expression of glutamate-cysteine ligase, the rate-limiting enzyme in de novo synthesis of the major intracellular antioxidant, glutathione. De novo synthesis of glutathione was required for curcumin to suppress pdgf-betar and egfr expression in activated HSCs. Our results collectively demonstrated that enhancement of PPARgamma activity by curcumin interrupted PDGF and EGF signaling in activated HSCs by reducing the phosphorylation levels of PDGF-betaR and EGFR, and by suppressing the receptor gene expression. These results provide novel insights into the mechanisms of curcumin in the inhibition of HSC activation and the suppression of hepatic fibrogenesis.

Epigallocatechin-3-gallate inhibits growth of activated hepatic stellate cells by enhancing the capacity of glutathione synthesis

Activation of hepatic stellate cells (HSC), the key effectors in hepatic fibrogenesis, is characterized by enhanced cell proliferation and overproduction of extracellular matrix. Oxidative stress promotes HSC activation. Glutathione (GSH) is the most important intracellular antioxidant, whose synthesis is mainly regulated by glutamate-cysteine ligase (GCL). We reported previously that (-)-epigallocatechin-3-gallate (EGCG), the major and most active component in green tea extracts, inhibited HSC activation. The aim of this study is to elucidate the underlying mechanisms. We hypothesize that this inhibitory effect of EGCG might mainly result from its antioxidant capability by increasing de novo synthesis of GSH. In this report, we observe that EGCG enhances the levels of cytoplasmic and mitochondrial GSH and increases GCL activity by inducing gene expression of the catalytic subunit GCLc, leading to de novo synthesis of GSH. Real-time polymerase chain reaction and Western blotting analyses show that de novo synthesis of GSH is required for EGCG to regulate the expression of genes relevant to apoptosis and to cell proliferation. Additional experiments demonstrate that exogenous transforming growth factor (TGF)-beta1 suppresses GCLc gene expression and reduces the level of GSH in cultured HSC. Transient transfection assays and Western blotting analyses further display that EGCG interrupts TGF-beta signaling by reducing gene expression of TGF-beta receptors and Smad4, leading to increased expression of GCLc. These results support our hypothesis and collectively demonstrate that EGCG increases the level of cellular GSH in HSC by stimulating gene expression of GCLc, leading to the inhibition of cell proliferation of activated HSC in vitro.

Activation of stem cells in hepatic diseases

The liver has enormous regenerative capacity. Following acute liver injury, hepatocyte division regenerates the parenchyma but, if this capacity is overwhelmed during massive or chronic liver injury, the intrinsic hepatic progenitor cells (HPCs) termed oval cells are activated. These HPCs are bipotential and can regenerate both biliary epithelia and hepatocytes. Multiple signalling pathways contribute to the complex mechanism controlling the behaviour of the HPCs. These signals are delivered primarily by the surrounding microenvironment. During liver disease, stem cells extrinsic to the liver are activated and bone-marrow-derived cells play a role in the generation of fibrosis during liver injury and its resolution. Here, we review our current understanding of the role of stem cells during liver disease and their mechanisms of activation.

Curcumin protects the rat liver from CCl4-caused injury and fibrogenesis by attenuating oxidative stress and suppressing inflammation

We previously demonstrated that curcumin, a polyphenolic antioxidant purified from turmeric, up-regulated peroxisome proliferator-activated receptor (PPAR)-gamma gene expression and stimulated its signaling, leading to the inhibition of activation of hepatic stellate cells (HSC) in vitro. The current study evaluates the in vivo role of curcumin in protecting the liver against injury and fibrogenesis caused by carbon tetrachloride (CCl(4)) in rats and further explores the underlying mechanisms. We hypothesize that curcumin might protect the liver from CCl(4)-caused injury and fibrogenesis by attenuating oxidative stress, suppressing inflammation, and inhibiting activation of HSC. This report demonstrates that curcumin significantly protects the liver from injury by reducing the activities of serum aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase, and by improving the histological architecture of the liver. In addition, curcumin attenuates oxidative stress by increasing the content of hepatic glutathione, leading to the reduction in the level of lipid hydroperoxide. Curcumin dramatically suppresses inflammation by reducing levels of inflammatory cytokines, including interferon-gamma, tumor necrosis factor-alpha, and interleukin-6. Furthermore, curcumin inhibits HSC activation by elevating the level of PPARgamma and reducing the abundance of platelet-derived growth factor, transforming growth factor-beta, their receptors, and type I collagen. This study demonstrates that curcumin protects the rat liver from CCl(4)-caused injury and fibrogenesis by suppressing hepatic inflammation, attenuating hepatic oxidative stress and inhibiting HSC activation. These results confirm and extend our prior in vitro observations and provide novel insights into the mechanisms of curcumin in the protection of the liver. Our results suggest that curcumin might be a therapeutic antifibrotic agent for the treatment of hepatic fibrosis.

FR-167653, a selective p38 MAPK inhibitor, exerts salutary effect on liver cirrhosis through downregulation of Runx2

Liver cirrhosis remains a difficult-to-treat disease with a substantial morbidity and mortality rate. There is an emerging body of data purporting a pivotal role of the activated p38 mitogen-activated protein kinase (MAPK) in the process of cirrhosis. Several anticirrhotic agents have been developed over the past few years, and most of them exert their effects by indirectly inhibiting the p38 pathway. Effect of a selective p38 inhibitor is yet to be reported. In this study, we evaluated the salutary effect of FR-167653 (FR), a selective p38 inhibitor, in a carbon tetrachloride (CCl(4))-induced rat cirrhotic model. Twenty rats were assigned into four groups: Sham, olive oil only; Control, CCl(4) in olive oil; FR50, FR 50 mg/kg/day and CCl(4); and FR100, FR 100 mg/kg/day and CCl(4). FR dose-dependently inhibited activation of p38 and had an ameliorating effect on cirrhosis formation. Significant dose-dependent reduction in alpha-smooth muscle actin immunostaining and hydroxyproline content of the liver was noticed in the FR-treated rats. Also densitometric analysis showed a significant reduction in azan-stained area in the FR-treated rats. These fibrotic changes were observed in the myofibroblasts including the hepatic stellate cells and portal fibroblasts. mRNA expression of runt-related protein 2 (Runx2), a profibrogenic transcription factor, was significantly low in FR-treated livers, indicating that Runx2 might be a key downstream regulator of the p38 pathway. A similar reduction in expression of Smad4 and tissue inhibitor of metalloproteinase-1 was noticed in the FR-treated rats. In conclusion, FR treatment exerted a significant beneficial effect in a CCl(4)-induced rat cirrhotic model. The ameliorating effect of FR could be partially attributable to an inhibition of the Smad4/p38/Runx2 axis in the cirrhotic liver.

The interruption of the PDGF and EGF signaling pathways by curcumin stimulates gene expression of PPARgamma in rat activated hepatic stellate cell in vitro

Activation of hepatic stellate cells (HSC), the major effector in hepatic fibrogenesis, is coupled with sequential alterations in expression of genes, including the upregulation of platelet-derived growth factor-beta receptor (PDGF-betaR) and epidermal growth factor receptor (EGFR), as well as the down-regulation of the peroxisome proliferator-activated receptor-gamma (PPARgamma). However, the relationship among the alterations in expression of the genes and the activation of their signaling in activated HSC remains obscure. We recently showed that curcumin, the yellow pigment in curry, inhibited cell growth and induced gene expression of endogenous PPARgamma in activated HSC in vitro. The present study is to elucidate the underlying mechanisms, focusing on the impacts of PDGF and EGF signaling. It is hypothesized that the interruption of the PDGF and EGF signaling pathways by curcumin might stimulate gene expression of PPARgamma in activated HSC. Our results in this report indicate that the activation of PDGF or EGF signaling by exogenous PDGF or EGF inhibits PPARgamma gene expression in passaged HSC. Curcumin interrupts PDGF and EGF signaling demonstrated by inhibiting tyrosine phosphorylation of PDGF-betaR and EGFR and by reducing the levels of phosphorylated phosphatidylinositol-3 kinase (PI-3K/AKT), extracellular signal-regulated kinase (ERK) and the Jun N-terminal kinase (JNK). The blockade of PI-3K/AKT, ERK or JNK signaling negatively regulates PPARgamma gene expression in activated HSC, leading to the reduction in cell growth, including inducing cell arrest and apoptosis. Our results collectively demonstrate that the interruption of the PDGF and EGF signaling pathways by curcumin stimulates gene expression of PPARgamma in activated HSC. These results provide novel insights into the mechanisms of curcumin in the induction of PPARgamma gene expression in activated HSC.

EGF-induced inhibition of glucose transport is mediated by PKC and MAPK signal pathways in primary cultured chicken hepatocytes

EGF is a regulator of a wide variety of processes in various cell systems. Hepatocytes are important sites in the body's metabolism and function. Glucose transporter 2 (GLUT2) is a major transporter that is expressed strongly in hepatocytes. Therefore, this study examined the effect of EGF on GLUT2 and its related signal cascades in primary cultured chicken hepatocytes. EGF decreased [(3)H]deoxyglucose uptake in a dose- and time-dependent manner (>10 ng/ml, 2 h). AG-1478 (an EGF receptor antagonist) and genistein and herbimycin A (tyrosine kinase inhibitors) blocked the EGF-induced decrease in [(3)H]deoxyglucose uptake, which correlated with the GLUT2 expression level. In addition, the EGF-induced decrease in GLUT2 protein expression was inhibited by staurosporine, H-7, or bisindolylmaleimide I (PKC inhibitors), PD-98059 (a MEK inhibitor), SB-203580 (a p38 MAPK inhibitor), and SP-600125 (a JNK inhibitor), suggesting a role of both PKC and MAPKs (p44/42 MAPK, p38 MAPK, and JNK). In particular, EGF increased the translocation of PKC isoforms (PKC-alpha, -beta(1), -gamma, -delta, and -zeta) from the cytosol to the membrane fraction and increased the activation of p44/42 MAPK, p38 MAPK, and JNK. Moreover, PKC inhibitors blocked the EGF-induced phosphorylation of three MAPKs. In conclusion, EGF decreases the GLUT2 expression level via the PKC-MAPK signal cascade in chicken hepatocytes.

The phyto-chemical (-)-epigallocatechin gallate suppresses gene expression of epidermal growth factor receptor in rat hepatic stellate cells in vitro by reducing the activity of Egr-1

Hepatic stellate cells (HSC) are the major effectors in hepatic fibrogenesis. During liver injury, HSC become activated and proliferative. Platelet-derived growth factor (PDGF) and epidermal growth factor (EGF) are the potent mitogens for many cell types. We previously demonstrated that (-)-epigallocatechin gallate (EGCG), the major and active component in green tea extracts, inhibited HSC growth, including reducing cell proliferation, and inducing apoptosis. We have reported that EGCG interrupts PDGF signaling by reducing receptor tyrosine phosphorylation and gene expression of PDGF-beta receptor. Additional experiments are necessary to elucidate the effect of EGCG on EGF signaling in activated HSC. The aims of this study are to evaluate the effect of EGCG on the expression of EGFR and to elucidate the underlying molecular mechanisms in activated HSC. We hypothesize that EGCG might interrupt EGF signaling by suppressing gene expression of EGF receptor (EGFR) in activated HSC, which, together with the interruption of PDGF signaling, might collectively result in the inhibition of HSC growth. The present report demonstrates that the phyto-chemical dose-dependently suppresses gene expression of EGFR in activated HSC in vitro. The Egr-1 binding site located in the egfr promoter is found to be cis-activating element in regulating the promoter activity of the gene. EGCG inhibits the trans-activation activity of Egr-1 in activated HSC by suppressing gene expression of the transcription factor. The interruption of the ERK signaling pathway by EGCG reduces the trans-activation activity of Egr-1 and the promoter activity of EGFR gene in HSC. Taken together, our results demonstrate that EGCG suppresses gene expression of EGFR in rat activated HSC in vitro mediated by reducing the trans-activation activity of Egr-1.

Hepatocyte production of modulators of extracellular liver matrix in normal and cirrhotic rat liver

In the present study, we found collagenolytic and gelatinolytic activity in the supernatants of hepatocyte cultures from rats with experimental CCl(4)-induced liver cirrhosis, in levels significantly higher than in comparable supernatants of hepatocyte cultures from normal rats. In addition, we clearly detected the messenger ribonucleic acids (mRNA) of four matrix metalloproteinases (MMP-2, MMP-3, MMP-10, and MMP-13) and of two tissue inhibitors of matrix metalloproteinases (TIMP-1 and TIMP-2) in hepatocytes from both normal and cirrhotic rats by RT-PCR and by in situ hybridization. Finally, we demonstrated MMP-2, MMP-3, and MMP-13 and TIMP-1 and TIMP-2 proteins in the same hepatocyte preparations by immunostaining. We conclude that rat hepatocytes produce the major enzymes and inhibitors involved in liver ECM modulation and therefore suggests that they might participate actively in the pathophysiology of liver cirrhosis in rats.

Expression of augmenter of liver regeneration (ALR) in human liver cirrhosis and carcinoma

AIMS

To determine the expression of a protein termed augmenter of liver regeneration (ALR), recently found to have a specific and beneficial effect on the process of liver regeneration in normal and diseased human liver.

METHODS AND RESULTS

ALR expression in normal and cirrhotic human livers with various underlying diseases as well as in tissue samples of hepatocellular carcinoma (HCC) and cholangiocellular carcinoma (CCC) was analysed by immunohistochemistry and quantitative reverse transciptase-polymerase chain reaction (RT-PCR). Expression analysis of ALR in total liver protein extracts by Western blotting showed mainly dimeric ALR protein. Immunohistochemically, cytosolic and perinuclear immunosignals were found in hepatocytes and cholangiocytes in normal, cirrhotic or cancerous liver tissue and only weak signals in some endothelial cells in normal livers. Quantitative mRNA analysis revealed significantly increased ALR expression in cirrhosis compared with normal liver tissue. In HCC and CCC ALR mRNA expression was also significantly enhanced compared with normal liver tissue, but expression levels did not differ from the matching non-neoplastic tissue in the same patient.

CONCLUSIONS

The findings suggest an important role for ALR in hepatocellular regeneration in liver cirrhosis as well as in hepatocarcinogenesis and therefore its potential value in the clinical diagnosis of hepatic cirrhosis and cancer.

Effect of IL-10 on the expression of HSC growth factors in hepatic fibrosis rat

AIM: To study the effect of IL-10 on the expression of growth factors - transforming growth factor-β1 (TGF-β1), epidermal growth factor (EGF), hepatocyte growth factor (HGF)and platelet-derived growth factor (PDGF) of hepatic stellate cells (HSCs) of hepatic fibrosis rat and the anti-fibrogenic role of exogenous IL-10.

METHODS: Hepatic fibrosis was induced by CCl4 administration intra-peritoneally. Sixty clean male Sprague-Dawley (SD) rats were randomly divided into three groups: normal control group (GN, 8 rats), hepatic fibrosis model group (GC, 28 rats) and IL-10 treated group (GI, 24 rats). At the beginning of the 7^th and 11^th wk, rats in each group were routinely perfused with pronase E and type IV collag-enase through a portal vein catheter and the suspension obtained from the liver was spun by centrifugation with 11% Nycodenz density gradient to isolate HSCs. Histological examination was used to determine the degree of hepatic fibrosis. RT-PCR was employed to analyze mRNA expression from freshly isolated cells. Immunocytochemistry was performed to detect protein expression in primary cultured HSCs.

RESULTS: Rat hepatic fibrosis was developed with the increase of injection frequency of CCl4, and HSCs were successfully isolated. At the 7^th and 11^th wk, TGF-β1, EGF, and HGF mRNA in GC increased obviously compared with GN (P = 0.001/0.042, 0.001/0.001, 0.001/0.001) and GI (P = 0.001/0.007, 0.002/0.001, 0.001/0.001). For TGF-β1, no difference was observed between GI and GN. For EGF, mRNA level in GI increased compared with GN during the 7^th wk (P = 0.005) and 11^th wk (P = 0.049). For HGF, mRNA level in GI decreased compared with GN at the 7^th wk (P = 0.001) and 11^th wk (P = 0.021). Between these two time points, TGF-β1 expression at the 7^th wk was higher than that of the 11^th wk (P = 0.049), but for EGF, the former was lower than the latter (P = 0.022). As for PDGF mRNA, there was no significant difference between these groups, but difference seemed to exist in protein levels. Results by immunocytochemistry of TGF-β1 and EGF were paralleled with the above findings.

CONCLUSION: The expression of TGF-β1, EGF and HGF increased in HSC of hepatic fibrosis rat and decreased after treatment with IL-10. IL-10 plays an anti-fibrogenic role by suppressing growth factors expression.