Characterization of six tumorsuppressor genes and microsatellite instability in hepatocellular carcinomain southern African blacks

AIM To analyse cumulative loss of heterozygosity (LOH) of chromosomal regions and tumor suppressor genes in hepatocellular carcinomas (HCCs) from 20 southern African blacks. METHODS p53, RB1, BRCA1, BRCA2, WT1 and E cadherin genes were analysed for LOH, and p53 gene was also analysed for the codon 249 mutation, in tumor and adjacent non tumorous liver tissues using molecular techniques and 10 polymorphic microsatellite markers. RESULTS p53 codon 249 mutation was found in 25% of the subjects, as was expected, because many patients were from Mozambique, a country with high aflatoxin B 1 exposure. LOH was found at the RB1, BRCA2 and WT1 loci in 20%(4/*!20) of the HCCs, supporting a possible role of these genes in HCC. No LOH was evident in any of the remaining genes. Reports of mutations of p53 and RB1 genes in combination, described in other populations, were not confirmed in this study. Change in microsatellite repeat number was noted at 9/*!10 microsatellite loci in different HCCs, and changes at two or more loci were detected in 15%(3/*!20) of subjects. CONCLUSION We propose that microsatellite/genomic instability may play a role in the pathogenesis of a subset of HCCs in black Africans.

Hepatitis B virus and hepatitis C virus dual infection

Hepatitis B virus(HBV)and hepatitis C virus(HCV)share common mode of transmission and both are able to induce a chronic infection.Dual HBV/HCV chronic coinfection is a fairly frequent occurrence,especially in high endemic areas and among individuals at high risk of parenterally transmitted infections.The intracellular interplay between HBV and HCV has not yet been sufficiently clarified,also due to the lack of a proper in vitro cellular model.Longitudinal evaluation of serum HBV DNA and HCV RNA amounts has revealed that complex virological profiles may be present in coinfected patients.Dual HBV/HCV infection has been associated to a severe course of the liver disease and to a high risk of developing hepatocellular carcinoma.Despite the clinical importance,solid evidence and clear guidelines for treatment of this special population are still lacking.This review summarizes the available data on the virological and clinical features as well as the therapeutic options of the dual HBV/HCV infection,and highlights the aspects that need to be better clarified.

A combination treatment of entecavir and early-phase corticosteroid in severe exacerbation of chronic hepatitis B

Of patients with severe exacerbation of chronic hepatitis B accompanied by jaundice and coagulopathy,20%-30%have a fatal outcome.In this report,we describe 2 cases of severe exacerbation of chronic hepatitis B with jaundice and coagulopathy who were successfully treated with a combination of entecavir and corticosteroid.In both cases,rapid reductions in serum hepatitis B virus(HBV)-DNA levels were observed,and corticosteroid was stopped after serum HBV-DNA levels became undetectable.Entecavir treatment was continued.Generally,entecavir treatment reduced serum HBV-DNA levels rapidly,although the improvement in liver function was delayed by a few weeks.During this time lag,liver cell injury continued and the disease progressed.Corticosteroid suppressed the excessive host immune response and was useful for stopping progressive deterioration.A combination of entecavir and early-phase corticosteroid may be a useful treatment in severe exacerbation of chronic hepatitis B.

Integration of hepatitis B virus DNA into chromosomal DNA during acute hepatitis B

AIM: To examine the serum from black African patients with acute hepatitis B to ascertain if integrants of viral DNA can be detected in fragments of cellular DNA leaking from damaged hepatocytes into the circulation.METHODS: DNA was extracted from the sera of five patients with uncomplicated acute hepatitis B and one with fulminant disease. Two subgenomic PCRs designed to amplify the complete genome of HBV were used and the resulting amplicons were cloned and sequenced.RESULTS: HBV and chromosomal DNA were amplified from the sera of all the patients. In one patient with uncomplicated disease, HBV DNA was integrated into host chromosome 7 q11.23 in the WBSCR1 gene. The viral DNA comprised 200 nucleotides covering the S and X genes in opposite orientation, with a 1 169 nudeotide deletion. The right virus/host junction was situated at nucleotide 1774 in the cohesive overlap region of the viral genome, at a preferred topoisomerase I cleavage motif. The chromosomal DNA was not rearranged.The patient made a full recovery and seroconverted to anti-HBs- and anti-HBe-positivity. Neither HBV nor chromosomal DNA could be amplified from his serum at that time.CONCLUSION: Integration of viral DNA into chromosomal DNA may occur rarely during acute hepatitis B and, with clonal propagation of the integrant, might play a role in hepatocarcinogenesis.

Nonalcoholic steatohepatitis-associated hepatocellular carcinoma:Our case series and literature review

Recently,nonalcoholic steatohepatitis(NASH) has been considered to be another cause of liver cirrhosis and hepatocellular carcinoma(HCC).The natural history and prognosis of NASH are controversial.Accordingly,we assessed the clinicopathological features of NASH-associated HCC in our experience and reviewed the literature of NASH-associated HCC.We experienced 11 patients with NASH-associated HCC(6 male,5 female;mean age 73.8 ± 4.9 years) who received curative treatments.Most(91%) patients had been diagnosed with obesity,diabetes,hypertension,or dyslipidemia.Seven patients(64%) also had a non-cirrhotic liver.The recurrence-free survival rates at 1,3 and 5 years were 72%,60%,and 60%.We also summarized and reviewed 94 cases of NASH-associated HCC which were reported in the literature(64 male;mean age 66 years).The majority of patients(68%) were obese,66% of patients had diabetes,and 24% had dyslipidemia.Furthermore,26% of the HCCs arose from the non-cirrhotic liver.In conclusion,patients with non-cirrhotic NASH may be a high-risk group for HCC,and regular surveillance for HCC is necessary in non-cirrhotic NASH patients as well as cirrhotic patients.

A case of hepatic angiomyolipoma difficult to distinguish from hepatocellular carcinoma

We report a case of hepatic angiomyolipoma with uncommon clinical features. A 56-year-old man presented with a hepatic tumor in the caudate lobe. The tumor was hypoechoic on ultrasonography, showed early-phase hyperattenuation on enhanced computed tomography and did not absorb iron on superparamagnetic iron oxide-enhanced magnetic resonance imaging. Hepatocellular carcinoma was highly suspected, and the patient underwent hepatic resection. Histologically, the tumor was mainly composed of smooth muscle cells and contained small amounts of adipose cells and blood vessels. On immunohistochemical staining, the smooth muscle cells were positive for a melanocytic cell-specific monoclonal antibody. In cases with uncommon features of angiomyolipoma, it is quite difficult to distinguish angiomyolipoma from hepatocellular carcinoma.

Computed tomography vs liver stiffness measurement and magnetic resonance imaging in evaluating esophageal varices in cirrhotic patients:A systematic review and meta-analysis

BACKGROUND Computed tomography(CT),liver stiffness measurement(LSM),and magnetic resonance imaging(MRI)are non-invasive diagnostic methods for esophageal varices(EV)and for the prediction of high-bleeding-risk EV(HREV)in cirrhotic patients.However,the clinical use of these methods is controversial.AIM To evaluate the accuracy of LSM,CT,and MRI in diagnosing EV and predicting HREV in cirrhotic patients.METHODS We performed literature searches in multiple databases,including Pub Med,Embase,Cochrane,CNKI,and Wanfang databases,for articles that evaluated the accuracy of LSM,CT,and MRI as candidates for the diagnosis of EV and prediction of HREV in cirrhotic patients.Summary sensitivity and specificity,positive likelihood ratio and negative likelihood ratio,diagnostic odds ratio,and the areas under the summary receiver operating characteristic curves were analyzed.The quality of the articles was assessed using the quality assessment of diagnostic accuracy studies-2 tool.Heterogeneity was examined by Q-statistic test and I2 index,and sources of heterogeneity were explored using metaregression and subgroup analysis.Publication bias was evaluated using Deek’s funnel plot.All statistical analyses were conducted using Stata12.0,Meta Disc1.4,and Rev Man5.3.RESULTS Overall,18,17,and 7 relevant articles on the accuracy of LSM,CT,and MRI in evaluating EV and HREV were retrieved.A significant heterogeneity was observed in all analyses(P<0.05).The areas under the summary receiver operating characteristic curves of LSM,CT,and MRI in diagnosing EV and predicting HREV were 0.86(95%confidence interval[CI]:0.83-0.89),0.91(95%CI:0.88-0.93),and 0.86(95%CI:0.83-0.89),and 0.85(95%CI:0.81-0.88),0.94(95%CI:0.91-0.96),and 0.83(95%CI:0.79-0.86),respectively,with sensitivities of 0.84(95%CI:0.78-0.89),0.91(95%CI:0.87-0.94),and 0.81(95%CI:0.76-0.86),and 0.81(95%CI:0.75-0.86),0.88(95%CI:0.82-0.92),and 0.80(95%CI:0.72-0.86),and specificities of 0.71(95%CI:0.60-0.80),0.75(95%CI:0.68-0.82),and 0.82(95%CI:0.70-0.89),and 0.73(95%CI:0.66-0.80),0.87(95%CI:0.81-0.92),and 0.72(95%CI:0.62-0.80),respectively.The corresponding positive likelihood ratios were 2.91,3.67,and 4.44,and 3.04,6.90,and2.83;the negative likelihood ratios were 0.22,0.12,and 0.23,and 0.26,0.14,and 0.28;the diagnostic odds ratios were 13.01,30.98,and 19.58,and 11.93,49.99,and 10.00.CT scanner is the source of heterogeneity.There was no significant difference in diagnostic threshold effects(P>0.05)or publication bias(P>0.05).CONCLUSION Based on the meta-analysis of observational studies,it is suggested that CT imaging,a non-invasive diagnostic method,is the best choice for the diagnosis of EV and prediction of HREV in cirrhotic patients compared with LSM and MRI.

Alanine and aspartate aminotransferase and glutamine-cycling pathway:Their roles in pathogenesis of metabolic syndrome

Although new research technologies are constantly used to look either for genes or biomarkers in the prediction of metabolic syndrome(MS),the pathogenesis and pathophysiology of this complex disease remains a major challenge.Interestingly,Cheng et al recently investigated possible pathways underlying MS by high-throughput metabolite profiling in two large and well characterized community-based cohorts.The authors explored by liquid chromatography and mass spectrometry the plasma concentrations of 45 distinct metabolites and examined their relation to cardiometabolic risk,and observed that metabolic risk factors such as obesity,insulin resistance(IR),high blood pressure,and dyslipidemia were associated with several metabolites,including branched-chain amino acids,other hydrophobic amino acids,tryptophan breakdown products,and nucleotide metabolites.In addition,the authors found a significant association of IR traits with glutamine,glutamate and the glutamineto-glutamate ratio.These data provide new insight into the pathogenesis of MS-associated phenotypes and introduce a crucial role of glutamine-cycling pathway as prominently involved in the development of metabolic risk.We consider that the hypothesis about the role of abnormal glutamate metabolism in the pathogenesis of the MS is certainly challenging and suggests the critical role of the liver in the global metabolic modulation as glutamate metabolism is linked with aminotransferase reactions.We discuss here the critical role of the "liver metabolism" in the pathogenesis of the MS and IR,and postulate that before fatty liver develops,abnormal levels of liver enzymes,such as alanine and aspartate aminotransferases might reflect high levels of hepatic transamination of amino acids in the liver.

Review of the diagnosis and management of gastrointestinal bezoars

The formation of a bezoar is a relatively infrequentdisorder that affects the gastrointestinal system.Bezoars are mainly classified into four types dependingon the material constituting the indigestible mass of thebezoar phytobezoars, trichobezoars, pharmacobezoars,and lactobezoars. Gastric bezoars often cause ulcerativelesions in the stomach and subsequent bleeding,whereas small intestinal bezoars present with smallbowel obstruction and ileus. A number of articles haveemphasized the usefulness of Coca-Cola？ administrationfor the dissolution of phytobezoars. However, persimmonphytobezoars may be resistant to such dissolutiontreatment because of their harder consistency comparedto other types of phytobezoars. Better understanding ofthe etiology and epidemiology of each type of bezoarwill facilitate prompt diagnosis and management.Here we provide an overview of the prevalence, classification,predisposing factors, and manifestations ofbezoars. Diagnosis and management strategies arealso discussed, reviewing mainly our own case series.Recent progress in basic research regarding persimmonphytobezoars is also briefly reviewed.

Liver enzymes,metabolomics and genome-wide association studies:From systems biology to the personalized medicine

For several decades,serum levels of alanine(ALT) and aspartate(AST) aminotransferases have been regarded as markers of liver injury,including a wide range of etiologies from viral hepatitis to fatty liver.The increasing worldwide prevalence of metabolic syndrome and cardiovascular disease revealed that transaminases are strong predictors of type 2 diabetes,coronary heart disease,atherothrombotic risk profile,and overall risk of metabolic disease.Therefore,it is plausible to suggest that aminotransferases are surrogate biomarkers of "liver metabolic functioning" beyond the classical concept of liver cellular damage,as their enzymatic activity might actually reflect key aspects of the physiology and pathophysiology of the liver function.In this study,we summarize the background information and recent findings on the biological role of ALT and AST,and review the knowledge gained from the application of genome-wide approaches and "omics" technologies that uncovered new concepts on the role of aminotransferases in human diseases and systemic regulation of metabolic functions.Prediction of biomolecular interactions between the candidate genes recently discovered to be associated with plasma concentrations of liver enzymes showed interesting interconnectivity nodes,which suggest that regulation of aminotransferase activity is a complex and highly regulated trait.Finally,links between aminotransferase genes and metabolites are explored to understand the genetic contributions to the metabolic diversity.

Multiomics biomarkers for the prediction of nonalcoholic fatty liver disease severity

This review intends to uncover how information from large-scale genetic profiling(whole genome sequencing, and whole exome sequencing) of nonalcoholic fatty liver disease(NAFLD), as well as information from circulating transcriptomics(cell-free mi RNAs) and metabolomics, contributes to the understanding of NAFLD pathogenesis. A further aim is to address the question of whether OMICs information is ready to be implemented in the clinics. The available evidence suggests that any new knowledge pertaining to molecular signatures associated with NAFLD and nonalcoholic steatohepatitis should be promptly translated into the clinical setting. Nevertheless, rigorous steps that must include validation and replication are mandatory before utilizing OMICs biomarkers in diagnostics to identify patients at risk of advanced disease, including liver cancer.

PNPLA3,the triacylglycerol synthesis/hydrolysis/storage dilemma,and nonalcoholic fatty liver disease

Genome-wide and candidate gene association studies have identified several variants that predispose individuals to developing nonalcoholic fatty liver disease(NAFLD).However,the gene that has been consistently involved in the genetic susceptibility of NAFLD in humans is patatin-like phospholipase domain containing 3(PNPLA3,also known as adiponutrin).A nonsynonymous single nucleotide polymorphism in PNPLA3(rs738409 C/G,a coding variant that encodes an amino acid substitution I148M) is significantly associated with fatty liver and histological disease severity,not only in adults but also in children.Nevertheless,how PNPLA3 influences the biology of fatty liver disease is still an open question.A recent article describes new aspects about PNPLA3 gene/protein function and suggests that the I148M variant promotes hepatic lipid synthesis due to a gain of function.We revise here the published data about the role of the I148M variant in lipogenesis/lipolysis,and suggest putative areas of future research.For instance we explored in silico whether the rs738409 C or G alleles have the ability to modify miRNA binding sites and miRNA gene regulation,and we found that prediction of PNPLA3 target miRNAs shows two miRNAs potentially interacting in the 3' UTR region(hsa-miR-769-3p and hsa-miR-516a-3p).In addition,interesting unanswered questions remain to be explored.For example,PNPLA3 lies between two CCCTC-binding factor-bound sites that could be tested for insulator activity,and an intronic histone 3 lysine 4 trimethylation peak predicts an enhancer element,corroborated by the DNase Ⅰ hypersensitivity site peak.Finally,an interaction between PNPLA3 and glycerol3-phosphate acyltransferase 2 is suggested by data miming.

Follow up of infection of chacma baboons with inoculum containing a and non-a genotypes of hepatitis B virus

AIM: To determine whether one genotype (A or non-A genotypes of HBV) predominated over the other during the course of HBV infection.METHODS: Four baboons were inoculated with HBV. DNA was extracted from serum obtained at monthly intervals postinoculation for 52 weeks and HBV DNA was amplified using primers specific for the core region containing an insert characteristic of genotype A (nt 2 354-2 359, numbering from the EcoRI site). The amplicons were cloned into PCRScriptTM and a minimum of 15 clones per time point were sequenced in both directions.RESULTS: Both genotypes persisted for the entire followup period of 52 weeks. Genotype non-A predominated in two baboons and genotype A in one baboon. Neither genotype predominated in the fourth baboon, as shown at a 5 % level of testing.CONCLUSION: No conclusions concerning the dominance of either genotype or the natural progression or replication rates of HBV could be drawn because the pattern of the genotypes found may have been caused by sampling fluctuations at the time of DNA extraction and cloning as a result of the very low viral loads in the baboon sera.

Role of interleukin-1 and its antagonism of hepatic stellate cell proliferation and liver fibrosis in the Abcb4^(-/-) mouse model

AIM: To study the interleukin-1(IL-1) pathway as a therapeutic target for liver fibrosis in vitro and in vivo using the ATP-binding cassette transporter b4^(-/-)(Abcb4^(-/-)) mouse model.METHODS: Female and male Abcb4^(-/-) mice from 6 to 13 mo of age were analysed for the degree of cholestasis(liver serum tests), extent of liver fibrosis(hydroxyproline content and Sirius red staining) and tissue-specific activation of signalling pathways such as the IL-1 pathway [quantitative polymerase chain reaction(q PCR)]. For in vivo experiments, murine hepatic stellate cells(HSCs) were isolated via pronasecollagenase perfusion followed by density gradient centrifugation using female mice. Murine HSCs were stimulated with up to 1 ng/m L IL-1β with or without 2.5 μg/m L Anakinra, an IL-1 receptor antagonist, respectively. The proliferation of murine HSCs was assessed via the Brd U assay. The toxicity of Anakinra was evaluated via the fluorescein diacetate hydrolysis(FDH) assay. In vivo 8-wk-old Abcb4^(-/-) mice with an already fully established hepatic phenotype were treated with Anakinra(1 mg/kg body-weight daily intraperitoneally) or vehicle and liver injury and liver fibrosis were evaluated via serum tests, q PCR, hydroxyproline content and Sirius red staining. RESULTS: Liver fibrosis was less pronounced in males than in female Abcb4^(-/-) animals as defined by a lower hydroxyproline content(274 ± 64 μg/g vs 436 ± 80 μg/g liver, respectively; n = 13-15; P < 0.001; MannWhitney U-test) and lower m RNA expression of the profibrogenic tissue inhibitor of metalloproteinase-1(TIMP)(1 ± 0.41 vs 0.66 ± 0.33 fold, respectively; n = 13-15; P < 0.05; Mann-Whitney U-test). Reduced liver fibrosis was associated with significantly lower levels of F4/80 m RNA expression(1 ± 0.28 vs 0.71 ± 0.41 fold, respectively; n = 12-15; P < 0.05; Mann-Whitney U-test) and significantly lower IL-1β m RNA expression levels(1 ± 0.38 vs 0.44 ± 0.26 fold, respectively; n = 13-15; P < 0.001; Mann-Whitney U-test). No gender differences in the serum liver parameters [bilirubin; alanine aminotransferase(ALT); aspartate aminotransferase and alkaline phosphatase(AP)] were found. In vitro, the administration of IL-1β resulted in a significant increase in HSC proliferation [0.94 ± 0.72 arbitrary units(A.U.) in untreated controls, 1.12 ± 0.80 A.U. at an IL-1β concentration of 0.1 ng/m L and 1.18 ± 0.73 A.U. at an IL-1β concentration of 1 ng/m L in samples from n = 6 donor animals; P < 0.001; analyses of variance(ANOVA)]. Proliferation was reduced significantly by the addition of 2.5 μg/m L Anakinra(0.81 ± 0.60 A.U. in untreated controls, 0.92 ± 0.68 A.U. at an IL-1β concentration of 0.1 ng/m L, and 0.91 ± 0.69 A.U. at an IL-1β concentration of 1 ng/m L; in samples from n = 6 donor animals; P < 0.001; ANOVA) suggesting an anti-proliferative effect of this clinically approved IL-1 receptor antagonist. The FDH assay showed this dose to be non-toxic in HSCs. In vivo, Anakinra had no effect on the hepatic hydroxyprolinecontent, liver serum tests(ALT and AP) and profibrotic(collagen 1α1, collagen 1α2, transforming growth factor-β, and TIMP-1) and anti-fibrotic [matrix metalloproteinase 2(MMP2), MMP9 and MMP13 ] gene expression after 4 wk of treatment. Furthermore, the hepatic IL-1β and F4/80 m RNA expression levels were unaffected by Anakinra treatment.CONCLUSION: IL-1β expression is associated with the degree of liver fibrosis in Abcb4^(-/-) mice and promotes HSC proliferation. IL-1 antagonism shows antifibrotic effects in vitro but not in Abcb4^(-/-) mice.

Chemotherapy for advanced hepatocellular carcinoma in the sorafenib age

The kinase inhibitor sorafenib is the only systemic therapy proven to have a positive effect on survival of patients with advanced hepatocellular carcinoma(HCC).After development of sorafenib and its introduction as a therapeutic agent used in the clinic,several critical questions have been raised.Clinical parameters and biomarkers predicting sorafenib efficacy are the most important issues that need to be elucidated.Although it is difficult to know the responders in advance using conventional characteristics of patients,there are specific serum cytokines and/or gene amplification in tumor tissues that have been reported to predict efficacy of sorafenib.Risk and benefits of continuation of sorafenib beyond radiological progression is another issue to consider because no other standard therapy for advanced HCC as yet exists.In addition,effectiveness of the expanded application of sorafenib is still controversial,although a few studies have shed some light on combinational treatment with sorafenib for intermediate-stage HCC.Recently,over 50 relevant drugs have been developed and are currently under investigation.The efficacy of some of these drugs has been extensively examined,but none have demonstrated any superiority over sorafenib,so far.However,there are several drugs that have shown efficacy for treatment after sorafenib failure,and these are proceeding to further studies.To address these issues and questions,we have done extensive literature review and summarize the most current status of therapeutic application of sorafenib.

Can a fibrotic liver afford epithelial-mesenchymal transition?

The question whether epithelial-mesenchymal transition(EMT) occurs during liver fibrogenesis is a controversial issue. In vitro studies confirm that hepatocytes or cholangiocytes undergo EMT upon transforming growth factor β(TGF-β) stimulation, whereas in vivo experiments based on genetic fate mapping of specific cell populations suggest that EMT does not occur in fibrotic animal models. In this review we present current data supporting or opposing EMT in chronic liver disease and discuss conditions for the occurrence of EMT in patients. Based on the available data and our clinical observations we hypothesize that EMT-like alterations in liver cirrhosis are a side effect of high levels of TGF-β and other pro-fibrotic mediators rather than a biological process converting functional parenchyma, i.e., hepatocytes, into myofibroblasts at a time when essential liver functions are deteriorating.

Repurposing drugs to target nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease(NAFLD) is a complex disorder that has evolved in recent years as the leading global cause of chronic liver damage. The main obstacle to better disease management pertains to the lack of approved pharmacological interventions for the treatment of nonalcoholic steatohepatitis(NASH) and NASH-fibrosis-the severe histological forms. Over the past decade,tremendous advances have been made in NAFLD research, resulting in the discovery of disease mechanisms and novel therapeutic targets. Hence, a large number of pharmacological agents are currently being tested for safety and efficacy. These drugs are in the initial pharmacological phases(phase 1 and 2),which involve testing tolerability, therapeutic action, and pharmacological issues.It is thus reasonable to assume that the next generation of NASH drugs will not be available for clinical use for foreseeable future. The expected delay can be mitigated by drug repurposing or repositioning, which essentially relies on identifying and developing new uses for existing drugs. Here, we propose a drug candidate selection method based on the integration of molecular pathways of disease pathogenesis into network analysis tools that use OMICs data as well as multiples sources, including text mining from the medical literature.

Regulation of dipeptidyl peptidase 8 and 9 expression in activated lymphocytes and injured liver

AIM:To investigate the expression of dipeptidyl peptidase(DPP) 8 and DPP9 in lymphocytes and various models of liver fibrosis.METHODS:DPP8 and DPP9 expression were measured in mouse splenic CD4 + T-cells,CD8 + T-cells and B-cells(B220 +),human lymphoma cell lines and mouse splenocytes stimulated with pokeweed mitogen(PWM) or lipopolysaccharide(LPS),and in dithiothreitol(DTT) and mitomycin-C treated Raji cells.DPP8 and DPP9 expression were measured in epidermal growth factor(EGF) treated Huh7 hepatoma cells,in fibrotic liver samples from mice treated with carbon tetrachloride(CCl 4) and from multidrug resistance gene 2(Mdr2 /Abcb4) gene knockout(gko) mice with biliary fibrosis,and in human end stage primary biliary cirrhosis(PBC).RESULTS:All three lymphocyte subsets expressed DPP8 and DPP9 mRNA.DPP8 and DPP9 expression were upregulated in both PWM and LPS stimulated mouse splenocytes and in both Jurkat T-and Raji B-cell lines.DPP8 and DPP9 were downregulated in DTT treated and upregulated in mitomycin-C treated Raji cells.DPP9transfected Raji cells exhibited more annexin V + cells and associated apoptosis.DPP8 and DPP9 mRNA were upregulated in CCl 4 induced fibrotic livers but not in the lymphocytes isolated from such livers,while DPP9 was upregulated in EGF stimulated Huh7 cells.In contrast,intrahepatic DPP8 and DPP9 mRNA expression levels were low in the Mdr2 gko mouse and in human PBC compared to non-diseased livers.CONCLUSION:These expression patterns point to biological roles for DPP8 and DPP9 in lymphocyte activation and apoptosis and in hepatocytes during liver disease pathogenesis.

Smad7 dependent expression signature highlights BMP2 and HK2 signaling in HSC transdifferentiation

AIM: To analyse the influence of Smad7, antagonist of transforming growth factor (TGF)-β canonical signaling pathways on hepatic stellate cell (HSC) transdifferentia-tion in detail. METHODS: We systematically analysed genes regulated by TGF-β/Smad7 in activated HSCs by microarray analy-sis and validated the results using real time polymerase chain reaction and Western blotting analysis. RESULTS: We identif ied 100 known and unknown tar-gets underlying the regulation of Smad7 expression and delineated 8 gene ontology groups. Hk2, involved in glycolysis, was one of the most downregulated proteins, while BMP2, activator of the Smad1/5/8 pathway, was extremely upregulated by Smad7. However, BMP2 de-pendent Smad1 activation could be inhibited in vitro by Smad7 overexpression in HSCs. CONCLUSION: We conclude (1) the existence of a tight crosstalk of TGF-β and BMP2 pathways in HSCs and (2) a Smad7 dependently decreased sugar metabolism ameliorates HSC activation probably by energy with-drawal.

Monoacylglycerol lipase reprograms lipid precursors signaling in liver disease

Dietary oversupply of triglycerides represent the hallmark of obesity and connected complications in the liver such as non-alcoholic fatty liver disease and non-alcoholic steatohepatitis,which eventually progress to cirrhosis and hepatocellular carcinoma.Monoacylglycerol lipase is the last enzymatic step in the hydrolysis of triglycerides,generating glycerol and fatty acids(FAs),which are signaling precursors in physiology and disease.Notably,monoacylglycerol lipase(MGL)also hydrolyzes 2-arachidonoylglycerol,which is a potent ligand within the endocannabinoid system,into arachidonic acid-a precursor for prostaglandin synthesis;thus representing a pivotal substrates provider in multiple organs for several intersecting biological pathways ranging from FA metabolism to inflammation,pain and appetite.MGL inhibition has been shown protective in limiting several liver diseases as FAs may drive hepatocyte injury,fibrogenesis and de-activate immune cells,however the complexity of MGL network system still needs further and deeper understanding.The present review will focus on MGL function and FA partitioning in the horizons of liver disease.