0000000000025913
AUTHOR
Andreas Teufel
In silico characterization of LZTS3, a potential tumor suppressor
Members of the leucine zipper tumor suppressor (LZTS) protein family are thought to play roles in cell growth modulation. The two currently known members were identified by analyzing genomic and chromosomal alterations reported to be either involved or deleted in various types of cancer, suggesting a causative relationship. By means of computational biology, we have now identified a novel member of the LZTS protein family named LZTS3. The corresponding gene was localized to chromosome 20p13 and consisted of three exons. The novel LZTS3 protein demonstrated a high similarity to LAPSER1/LZTS2 and FEZ1/LZTS1, two members of the LZTS family. The conserved FEZ1 domain contains a leucine zipper m…
P0926 : Representation of human non-alcoholic fatty liver disease in murine models
COX-2 enhances insulin signaling. Finally, the relationship between COX-2 and the miRNAs was confirmed in NAS. Conclusions: COX-2 represses the expression of miRNAs implicated in the insulin signaling pathway via a PI3K/p300-dependent upregulation of DDX5, and by modulating the activity of the Drosha complex. Our study proposes a novel miRNA-dependent mechanism through which COX-2 promotes insulin signaling in liver cells.
Snapshot liver transcriptome in hepatocellular carcinoma
Lately, advances in high throughput technologies in biomedical research have led to a dramatic increase in the accessibility of molecular insights at different levels of cancer biology such as genome, epigenome, transcriptome, proteome, and others. Among the diverse biological layers, the transcriptome has been most extensively studied especially due to the successful and broad introduction of the microarray technology. The future prospect of broad disposability of deep sequencing technology will furthermore lead to a more sensitive detection of lowly expressed transcripts and to an increase in the number of newly identified transcripts, but also to increase the discovery and characterizati…
Genetic association analysis identifies variants associated with disease progression in primary sclerosing cholangitis
ObjectivePrimary sclerosing cholangitis (PSC) is a genetically complex, inflammatory bile duct disease of largely unknown aetiology often leading to liver transplantation or death. Little is known about the genetic contribution to the severity and progression of PSC. The aim of this study is to identify genetic variants associated with PSC disease progression and development of complications.DesignWe collected standardised PSC subphenotypes in a large cohort of 3402 patients with PSC. After quality control, we combined 130 422 single nucleotide polymorphisms of all patients—obtained using the Illumina immunochip—with their disease subphenotypes. Using logistic regression and Cox proportiona…
Heterozygous carriage of the alpha1-antitrypsin Pi*Z variant increases the risk to develop liver cirrhosis.
ObjectiveHomozygous alpha1-antitrypsin (AAT) deficiency increases the risk for developing cirrhosis, whereas the relevance of heterozygous carriage remains unclear. Hence, we evaluated the impact of the two most relevant AAT variants (‘Pi*Z’ and ‘Pi*S’), present in up to 10% of Caucasians, on subjects with non-alcoholic fatty liver disease (NAFLD) or alcohol misuse.DesignWe analysed multicentric case–control cohorts consisting of 1184 people with biopsy-proven NAFLD and of 2462 people with chronic alcohol misuse, both cohorts comprising cases with cirrhosis and controls without cirrhosis. Genotyping for the Pi*Z and Pi*S variants was performed.ResultsThe Pi*Z variant presented in 13.8% of p…
Acute renal failure and liver dysfunction after subcutaneous injection of 3-sn-phosphatidylcholine (Lipostabil®)-case report.
INTRODUCTION Drug-induced tubulointerstitial nephritis and acute tubular necrosis are common, and are often caused by drugs especially antibiotics or non-steroidal anti-inflammatory drugs. Drug-induced liver dysfunction and renal failure after subcutaneous injection of phosphatidylcholine was not reported so far. 3-sn-Phosphatidylcholine has been described as a cell lysis reaction-inducing drug. Its in vitro data indicated a relevant toxicity potential. In particular human cell types such as fibroblast-like preadipocytes, vascular and skeletal muscle cells, or renal epithelial cells react more sensitive than other human cell types. CASE REPORT We present a 28-year-old woman who received 3.5…
Activation of silent mating type information regulation 2 homolog 1 by human chorionic gonadotropin exerts a therapeutic effect on hepatic injury and inflammation
Incidence and prevalence of inflammatory liver diseases has increased over the last years, but therapeutic options are limited. Pregnancy induces a state of immune tolerance, which can result in spontaneous improvement of clinical symptoms of certain autoimmune diseases including autoimmune hepatitis (AIH). We investigated the immune-suppressive mechanisms of the human pregnancy hormone, chorionic gonadotropin (hCG), in the liver. hCG signaling activates silent mating type information regulation 2 homolog 1 (SIRT1), which deacetylates forkhead box o3 (FOXO3a), leading to repression of proapoptotic gene expression, because the immunosuppressive consequence attributed to the absence of caspas…
Intraflagellar transport protein 172 is essential for primary cilia formation and plays a vital role in patterning the mammalian brain
AbstractIFT172, also known as Selective Lim-domain Binding protein (SLB), is a component of the intraflagellar transport (IFT) complex. In order to evaluate the biological role of the Ift172 gene, we generated a loss-of-function mutation in the mouse. The resulting Slb mutant embryos die between E12.5 and 13.0, and exhibit severe cranio-facial malformations, failure to close the cranial neural tube, holoprosencephaly, heart edema and extensive hemorrhages. Cilia outgrowth in cells of the neuroepithelium is initiated but the axonemes are severely truncated and do not contain visible microtubules. Morphological and molecular analyses revealed a global brain-patterning defect along the dorsal–…
Chemotherapy-induced apoptosis in hepatocellular carcinoma involves the p53 family and is mediatedviathe extrinsic and the intrinsic pathway
We investigated the downstream mechanisms by which chemotherapeutic drugs elicit apoptosis in hepatocellular carcinoma (HCC). Genomic signatures of HCC cell lines treated with different chemotherapeutic drugs were obtained. Analyses of apoptosis pathways were performed and RNA interference was used to evaluate the role of the p53 family. Endogenous p53, p63 and p73 were upregulated in response to DNA damage by chemotherapeutic drugs. Blocking p53 family function led to chemoresistance in HCC. Stimulation and blocking experiments of the CD95-, the TNF- and the TRAIL-receptor systems revealed that cytotoxic drugs, via the p53 family members as transactivators, can trigger expression of each o…
TGF-β2 silencing to target biliary-derived liver diseases
ObjectiveTGF-β2 (TGF-β, transforming growth factor beta), the less-investigated sibling of TGF-β1, is deregulated in rodent and human liver diseases. Former data from bile duct ligated and MDR2 knockout (KO) mouse models for human cholestatic liver disease suggested an involvement of TGF-β2 in biliary-derived liver diseases.DesignAs we also found upregulated TGFB2 in liver tissue of patients with primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC), we now fathomed the positive prospects of targeting TGF-β2 in early stage biliary liver disease using the MDR2-KO mice. Specifically, the influence of TgfB2 silencing on the fibrotic and inflammatory niche was analysed on m…
Actin binding LIM protein 3 (abLIM3).
LIM domain proteins were demonstrated to play key roles in various biological processes such as embryonic development, cell lineage determination, and cancer differentiation. Actin binding LIM protein 1 (abLIM1) was reported to be localized in a genomic region often deleted in human cancers and suggested to be involved in axon guidance. Recently, existence of a second family member was reported, actin binding LIM protein 2. By means of computational biology and comparative genomics, we now characterized an additional, third member of the actin binding LIM protein subgroup, actin binding LIM protein 3 (abLIM3). The human mRNA sequence was previously annotated as differentially regulated in h…
Dense genotyping of immune-related disease regions identifies nine new risk loci for primary sclerosing cholangitis
To access publisher's full text version of this article click on the hyperlink at the bottom of the page Primary sclerosing cholangitis (PSC) is a severe liver disease of unknown etiology leading to fibrotic destruction of the bile ducts and ultimately to the need for liver transplantation. We compared 3,789 PSC cases of European ancestry to 25,079 population controls across 130,422 SNPs genotyped using the Immunochip. We identified 12 genome-wide significant associations outside the human leukocyte antigen (HLA) complex, 9 of which were new, increasing the number of known PSC risk loci to 16. Despite comorbidity with inflammatory bowel disease (IBD) in 72% of the cases, 6 of the 12 loci sh…
Concurrent autoimmune diseases in patients with autoimmune hepatitis.
Although the pathomechanisms of autoimmune diseases in various organs remain unresolved, an accumulation of autoimmune diseases in individual patients has been observed. An overlap of autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) or primary sclerosing cirrhosis has been well documented. However, the overlap of autoimmune diseases other than PBC or PSC has not yet been investigated in a large cohort.The goal of our analysis was to investigate the incidence of concurrent autoimmune diseases in patients with AIH.We analyzed our cohort of 278 patients with AIH for concurrent autoimmune diseases.A total of 111 patients (40%) were diagnosed with additional autoimmune diseases. Be…
Semiautomated quantification of the fibrous tissue response to complex three‐dimensional filamentous scaffolds using digital image analysis
Fibrosis represents a relevant response to the implantation of biomaterials, which occurs not only at the tissue-material interface (fibrotic encapsulation) but also within the void fraction of complex three-dimensional (3D) biomaterial constructions (fibrotic ingrowth). Usual evaluation of the biocompatibility mostly depicts fibrosis at the interface of the biomaterial using semiquantitative scores. Here, the relations between encapsulation and infiltrating fibrotic growth are poorly represented. Virtual pathology and digital image analysis provide new strategies to assess fibrosis in a more differentiated way. In this study, we adopted a method previously used to quantify fibrosis in visc…
102 NOVEL SUSCEPTIBILITY LOCI FOR PRIMARY SCLEROSING CHOLANGITIS IDENTIFIED BY GENOME-WIDE ASSOCIATION AND REPLICATION ANALYSIS
Increased liver carcinogenesis and enrichment of stem cell properties in livers of Dickkopf 2 (Dkk2) deleted mice.
// Thorsten Maass 1 , Jens Marquardt 2 , Ju-Seog Lee 3 , Markus Krupp 4 , Peter Scholz-Kreisel 2 , Carolin Mogler 5 , Peter Schirmacher 5 , Martina Muller 1 , Heiner Westphal 6 , Peter R. Galle 2 , Andreas Teufel 1 1 Department of Internal Medicine I, University of Regensburg, Regensburg, Germany 2 I. Department of Medicine, University Medical Center Mainz, Mainz, Germany 3 Cancer Biology Program, MD Anderson Cancer Center, Houston, TX, USA 4 Department of Informatics, Johannes Gutenberg University Mainz, Mainz, Germany 5 Institute of Pathology, University of Heidelberg, Heidelberg, Germany 6 Laboratory of Mammalian Genes and Development, National Institute of Child Health and Human Develop…
New Chemotherapeutic Strategies in Colorectal Cancer
Since colorectal cancer is the second most prevalent cancer worldwide, its treatment remains a major challenge for researchers, gastroenterologists and oncologists. Despite curative resections, half of all patients diagnosed with colorectal cancer die because of their underlying disease. Integral chemotherapeutic components of standard regimens are 5-fluorouracil (5-FU), its modulation by folinic acid and irinotecan or oxaliplatin. All these drugs sequentially given have results in terms of median overall survival of more than 20 months in the palliative treatment of advanced colorectal cancer. Oral fluoropyrimidines, currently under clinical investigation, are likely to substitute continuo…
A systems biology perspective on cholangiocellular carcinoma development: focus on MAPK-signaling and the extracellular environment.
Background/Aims Multiple genes have been implicated in cholangiocellular carcinoma (CCC) development. However, the overall neoplastic risk is likely associated with a much lower number of critical physiological pathways. Methods To investigate this hypothesis, we extracted all published genetic associations for the development of CCC from PubMed (genetic association studies, but also studies associating genes and CCC in general, i.e. functional studies in cell lines, genetic studies in humans, knockout mice etc.) and integrated CCC microarray data. Results We demonstrated the MAPK pathway was consistently enriched in CCC. Comparing our data to genetic associations in HCC often successfully …
Histone deacetylase inhibition by valproic acid down-regulates c-FLIP/CASH and sensitizes hepatoma cells towards CD95-and TRAIL receptor-mediated apoptosis and chemotherapy
Hepatocellular carcinoma (HCC) is highly resistant to chemotherapy, leading to a poor prognosis of advanced disease. Inhibitors of histone deacetylase (HDACi) induce re-differentiation in tumor cells and thereby re-establish sensitivity towards apoptotic stimuli. HDACi are entering the clinical stage of tumor treatment, and several substances are currently being tested in clinical trials to prove their efficacy in the treatment of leukemias and solid tumors. In this study, we investigated the impact of the HDACi valproic acid (VA) on TRAIL- and CD95-mediated apoptosis in hepatoma cells, as well as its sensitizing effect on a chemotherapeutic agent. Treatment of HepG2 cells with VA increased…
Molecular diagnosis and therapy of hepatocellular carcinoma (HCC): an emerging field for advanced technologies.
Despite great progress in diagnosis and management of hepatocellular carcinoma (HCC), the exact biology of the tumor remains poorly understood overall limiting the patients' outcome. Detailed analysis and characterization of the molecular mechanisms and subsequently individual prediction of corresponding prognostic traits would revolutionize both diagnosis and treatment of HCC and is the key goal of modern personalized medicine. Over the recent years systematic approaches for the analysis of whole tumor genomes and transcriptomes as well as epigenomes became affordable tools in translational research. This includes simultaneous analyses of thousands of molecular targets using microarray-bas…
Familial amyloidosis: great progress for an orphan disease.
Familial amyloidosis: Great progress for an orphan disease Ana Paula Barreiros1,2,*, Gerd Otto3, Bita Kahlen1, Andreas Teufel1,2, Peter R. Galle1 1Department of Internal Medicine I, Universitatsmedizin of the Johannes Gutenberg-University Mainz, Germany; 2Department of Internal Medicine I, Universitatsklinikum of the University Regensburg, Germany; 3Department of Hepatobiliary and Transplantation Surgery, Universitatmedizin of the Johannes Gutenberg-University Mainz, Germany. *Corresponding author. Address: Universitatsklinikum Regensburg, Department of Internal Medicine I, Franz-Josef-Strauss Allee 11, 93053 Regensburg, Germany. Tel.: +49 941-944-7021. E-mail address: Ana.Barreiros@ukr.de …
Mutational Characterization of the Bile Acid Receptor TGR5 in Primary Sclerosing Cholangitis
Background: TGR5, the G protein-coupled bile acid receptor 1 (GPBAR1), has been linked to inflammatory pathways as well as bile homeostasis, and could therefore be involved in primary sclerosing cholangitis (PSC) a chronic inflammatory bile duct disease. We aimed to extensively investigate TGR5 sequence variation in PSC, as well as functionally characterize detected variants.Methodology/Principal Findings: Complete resequencing of TGR5 was performed in 267 PSC patients and 274 healthy controls. Six nonsynonymous mutations were identified in addition to 16 other novel single-nucleotide polymorphisms. To investigate the impact from the nonsynonymous variants on TGR5, we created a receptor mod…
In silico characterization of an Iroquois family-related homeodomain protein.
Homeobox genes have been demonstrated to play important roles during cancer differentiation and embryonic development. The subset of Iroquois-related homeobox genes (IRXs) have furthermore been. demonstrated to be involved in several embryonic developmental processes such as patterning of the anterior-posterior and dorso-ventral axis, as well as specific regions of the central nervous system, and differentiation of the otic vesicle, branchial epithelium, and limbs. We have characterized a novel homeodomain protein and corresponding gene by means of computational biology. Since the protein sequence displayed high similarity to the human IRX proteins, the newly identified homeodomain protein …
Prognosis of patients with hepatocellular carcinoma treated with immunotherapy - development and validation of the CRAFITY score.
Immunotherapy with atezolizumab plus bevacizumab represents the new standard of care in systemic front-line treatment of hepatocellular carcinoma (HCC). However, biomarkers that predict treatment success and survival remain an unmet need.Patients with HCC put on PD-(L)1-based immunotherapy were included in a training set (n = 190; 6 European centers) and a validation set (n = 102; 8 European centers). We investigated the prognostic value of baseline variables on overall survival using a Cox model in the training set and developed the easily applicable CRAFITY (CRP and AFP in ImmunoTherapY) score. The score was validated in the independent, external cohort, and evaluated in a cohort of patie…
Genome-wide analysis of factors regulating gene expression in liver
In recent decades, multiple individual genes have been studied with respect to their level of expression in liver tissue and in many cases substantial progress has been made in identifying individual factors promoting gene expression in liver. However, the overall picture is still undefined and general rules or factors regulating gene expression in liver have not yet been established. Thus, a genome-wide screen for factors regulating gene expression in liver is of high interest, as it may reveal common regulatory mechanisms for most genes highly expressed in liver. These factors represent potential new targets in liver disease associated with differential gene expression. Using a novel bioi…
Predictive Scores in Primary Biliary Cirrhosis
GOALS The aim of this study was to assess the long-term outcome of primary biliary cirrhosis (PBC) patients and to test the clinical value of various outcome models, such as the Mayo Risk Score (MRS), in a large single-center cohort in Germany. BACKGROUND PBC is a chronic autoimmune liver disease with a female gender predominance and a peak incidence in the fifth decade of life. PBC is characterized by portal inflammation and immune-mediated destruction of intrahepatic bile ducts in liver histology and the presence of antimitochondrial antibodies in the serum of nearly 95% of patients. In 5% to 20% of patients an overlap syndrome with autoimmune hepatitis (AIH) is diagnosed. Ursodeoxycholic…
RNA-Seq Atlas—a reference database for gene expression profiling in normal tissue by next-generation sequencing
Abstract Motivation: Next-generation sequencing technology enables an entirely new perspective for clinical research and will speed up personalized medicine. In contrast to microarray-based approaches, RNA-Seq analysis provides a much more comprehensive and unbiased view of gene expression. Although the perspective is clear and the long-term success of this new technology obvious, bioinformatics resources making these data easily available especially to the biomedical research community are still evolving. Results: We have generated RNA-Seq Atlas, a web-based repository of RNA-Seq gene expression profiles and query tools. The website offers open and easy access to RNA-Seq gene expression pr…
Coexpression of receptor-tyrosine-kinases in gastric adenocarcinoma-a rationale for a molecular targeting strategy?
AIM: To define the (co-)expression pattern of target receptor-tyrosine-kinases (RTK) in human gastric adenocarcinoma. METHODS: The (co-)expression pattern of VEGFR1-3, PDGFRα/β and EGFR1 was analyzed by RT-PCR in 51 human gastric adenocarcinomas. In addition, IHC staining was applied for confirmation of expression and analysis of RTK localisation. RESULTS: The majority of samples revealed a VEGFR1 (98%), VEGFR2 (80%), VEGFR3 (67%), PDGFRα (82%) and PDGFRβ (82%) expression, whereas only 62% exhibited an EGFR1 expression. 78% of cancers expressed at least four out of six RTKs. While VEGFR1-3 and PDGFRα revealed a predominantly cytoplasmatic staining in tumor cells, accompanied by an additiona…
Extended analysis of a genome-wide association study in primary sclerosing cholangitis detects multiple novel risk loci
Background & Aims: A limited number of genetic risk factors have been reported in primary sclerosing cholangitis (PSC). To discover further genetic susceptibility factors for PSC, we followed up on,a second tier of single nucleotide polymorphisms (SNPs) from a genome-wide association study (GWAS). Methods: We analyzed 45 SNPs in 1221 PSC cases and 3508 controls. The association results from the replication analysis and the original GWAS (715 PSC cases and 2962 controls) were combined in a meta-analysis comprising 1936 PSC cases and 6470 controls. We performed an analysis of bile microbial community composition in 39 PSC patients by 16S rRNA sequencing. Results: Seventeen SNPs representing 1…
Dissemination of hepatocellular carcinoma is mediated via chemokine receptor CXCR4
In different tumour entities, expression of the chemokine receptor 4 (CXCR4) has been linked to tumour dissemination and poor prognosis. Therefore, we evaluated, if the expression of CXCR4 exerts similar effects in human hepatocellular carcinoma (HCC). Expression analysis and functional assays were performed in vitro to elucidate the impact of CXCL12 on human hepatoma cells lines. In addition, expression of CXCR4 was evaluated in 39 patients with HCC semiquantitatively and correlated with both, tumour and patients characteristics. Human HCC and hepatoma cell lines displayed variable intensities of CXCR4 expression. Loss of p53 function did not impact on CXCR4 expression. Exposure to CXCL12 …
Adaptive immunity suppresses formation and progression of diethylnitrosamine-induced liver cancer
Background Hepatocellular carcinoma (HCC) is a typical inflammation-associated cancer, but may also provoke antitumour immune responses whose significance and underlying mechanisms are incompletely understood. Objective To characterise immune responses in the diethylnitrosamine (DEN)-liver cancer mouse model. Design Tumour development and immune cell functions upon DEN treatment were compared between C57BL/6 wild-type (WT), chemokine scavenging receptor D6-deficient, B cell- (Igh6), CD4 T cell- (MHC-II) and T-/B cell-deficient (Rag1) mice. Relevance for human HCC was tested by comparing gene array results from 139 HCC tissues. Results The induction of premalignant lesions after 24 weeks and…
Current bioinformatics tools in genomic biomedical research (Review).
On the advent of a completely assembled human genome, modern biology and molecular medicine stepped into an era of increasingly rich sequence database information and high-throughput genomic analysis. However, as sequence entries in the major genomic databases currently rise exponentially, the gap between available, deposited sequence data and analysis by means of conventional molecular biology is rapidly widening, making new approaches of high-throughput genomic analysis necessary. At present, the only effective way to keep abreast of the dramatic increase in sequence and related information is to apply biocomputational approaches. Thus, over recent years, the field of bioinformatics has r…
BlotBase: a northern blot database.
With the availability of high-throughput gene expression analysis, multiple public expression databases emerged, mostly based on microarray expression data. Although these databases are of significant biomedical value, they do hold significant drawbacks, especially concerning the reliability of single gene expression profiles obtained by microarray data. Simultaneously, reliable data on an individual gene's expression are often published as single northern blots in individual publications. These data were not yet available for high-throughput screening. To reduce the gap between high-throughput expression data and individual highly reliable expression data, we designed a novel database "Blo…
949 IDENTIFICATION OF TWO CLINICALLY DISTINCT SUBTYPES IN AUTOIMMUNE HEPATITIS BY COMPARATIVE FUNCTIONAL GENOMICS
Conclusion: Incidence of autoimmune hepatitis is increasing, as other autoimmune diseases in developed countries. The main recognised hypothesis is the ‘hygienist theory’ (improvement of hygien leading to a decrease in infections) with few putative non exclusive mechanisms involving antigenic competition, extension of immune regulation induced by exogenous bacterial antigen or Toll Like Receptors.
Genome-Wide Association Analysis in Primary Sclerosing Cholangitis
Background & Aims We aimed to characterize the genetic susceptibility to primary sclerosing cholangitis (PSC) by means of a genome-wide association analysis of single nucleotide polymorphism (SNP) markers. Methods A total of 443,816 SNPs on the Affymetrix SNP Array 5.0 (Affymetrix, Santa Clara, CA) were genotyped in 285 Norwegian PSC patients and 298 healthy controls. Associations detected in this discovery panel were re-examined in independent case-control panels from Scandinavia (137 PSC cases and 368 controls), Belgium/The Netherlands (229 PSC cases and 735 controls), and Germany (400 cases and 1832 controls). Results The strongest associations were detected near HLA-B at chromosome 6p21…
Incidence of HAV and HBV infections and vaccination rates in patients with autoimmune liver diseases.
Hepatitis A virus (HAV) or hepatitis B virus (HBV) superinfection is associated with an increased mortality in patients with chronic liver diseases (CLD). Despite official recommendations, it was reported that the vaccination rate against HAV is low in patients with chronic hepatitis C infection. To evaluate the situation in patients with autoimmune liver diseases, we conducted a retrospective cohort study.Susceptibility to HAV and HBV infections, course of HAV and HBV infections, vaccination rates against HAV and HBV, and efficacy of hepatitis A/B vaccines were evaluated by antibody testing in 225 patients with autoimmune liver diseases during 1,677 person-years.Susceptibility to HAV/HBV i…
Hepatozelluläres Karzinom - molekulare Grundlagen und Zielmoleküle für die Therapie
Das hepatozellulare Karzinom zahlt zu den haufigsten Krebserkrankungen weltweit mit einer steigenden Inzidenz in westlichen Landern. Leberzellkarzinome zeichnen sich durch eine molekulare Vielfalt und ein schlechtes Therapieansprechen aus. Trotz groser Fortschritte in der Diagnostik und Behandlung des Leberzellkarzinoms in den letzten Jahren bleiben die Details der biochemischen Mechanismen weitestgehend unverstanden. Hierdurch wird die Entwicklung neuer Therapiestrategien erheblich erschwert. Die rasante Entwicklung von neuen Verfahren zur Analyse molekularer Mechanismen der Krebsentstehung auf verschiedenen molekularen Ebenen hat wesentlich zum Verstandnis der Hepatokarzinogenese beigetra…
Characterization of OEBT, a LIM protein
LIM Proteins have been demonstrated to play key roles in pattern formation during embryonic development, cell lineage determination, and cancer differentiation. These proteins are characterized by their conserved LIM domain, which functions as a specific protein-binding site. Recently, two new members of the LIM protein family, PRICKLE1 and PRICKLE2, were characterized in silico and demonstrated to be human orthologues of the Drosophila Prickle proteins. We report on an additional member of this protein family, over-expressed breast tumor protein (OEBT). The corresponding gene was mapped to human chromosome 6p22.31. Orthologues in mouse and rat with 72 and 54% identities on a protein level …
Liver-specific overexpression of matrix metalloproteinase 9 (MMP-9) in transgenic mice accelerates development of hepatocellular carcinoma.
Matrix metalloproteinase-9 (MMP-9) plays a central role in tumor invasion and development of metastases. Expression of MMP-9 had been shown in human hepatocellular carcinomas (HCCs). However, it remained unclear whether MMP-9 could influence development of HCC. In order to address this issue, we generated transgenic mice overexpressing MMP-9 in the liver. In order to avoid embryonic lethality a Cre-lox system was utilized for conditional overexpression of MMP-9 under control of an albumin enhancer and promoter. Induction of MMP-9 overexpression in transgenic mice was achieved by i.v. injection of an adenovirus coding for the Cre recombinase. Initiation of liver carcinogenesis was achieved b…
Der solid pseudopapilläre Pankreastumor (SPT) – eine seltene Raumforderung der Bauchspeicheldrüse
BACKGROUND: In general, the rare SPT is a tumour of low malignancy predominantly affecting young women. The outcome after radical resection is favourable. In exceptional cases the tumour presents as solid pseudopapillary carcinoma (SPC) with typical malignant features and even metastases. Unresectable liver metastases can be treated with RFA, TACE or chemotherapy. METHODS: We retrospectively reviewed the surgical approach, immunohistochemistry and clinical outcome in five female patients (1998 - 2007). RESULTS: The mean age was 16 years (range: 13 - 47 years). For radical tumour removal a pancreato - duodenectomy (n = 3), a distal pancreatectomy (n = 1) and an enucleation (n = 1) were perfo…
The longevity assurance homologue of yeast lag1 (Lass) gene family (Review)
The Lass gene family contains a group of highly conserved genes that are found in eukaryotic species. The founding member, lag1, was discovered in a screen for yeast longevity genes. Subsequently, lag1 homologs were discovered in other organisms including six mammalian paralogs. All Lass genes encode a highly conserved Lag1 domain and many also have an additional Hox domain. Lass proteins are ceramide synthases and therefore are critical for ceramide biosynthesis. Ceramide synthase is also a critical enzyme in the sphingolipid biosynthetic pathway. As ceramide and sphingolipids are key intermediates in diverse cellular processes such as cell growth, apoptosis, and stress response and may al…
Safety and Efficacy of Sorafenib in Patients With Advanced Hepatocellular Carcinoma in Consideration of Concomitant Stage of Liver Cirrhosis
GOALS AND BACKGROUND: The multikinase inhibitor sorafenib provides survival benefit for patients with advanced hepatocellular carcinoma (HCC) and liver cirrhosis (LCI) Child-Pugh A. We report our experiences with sorafenib in advanced HCC, particularly in patients with LCI Child-Pugh B/C, where only limited data are available in regard to safety and efficacy of sorafenib. METHODS: Thirty-four patients with advanced HCC were treated with sorafenib regardless of liver function and prior anticancer therapy. Adverse events (AEs) were graded using Common Toxicity Criteria version 3.0, tumor response was assessed according to Response Evaluation Criteria in Solid Tumors. RESULTS: Fifteen patients…
Hepatocyte-specific deletion of the antiapoptotic protein myeloid cell leukemia-1 triggers proliferation and hepatocarcinogenesis in mice
Regulation of hepatocellular apoptosis is crucial for liver homeostasis. Increased sensitivity of hepatocytes toward apoptosis results in chronic liver injury, whereas apoptosis resistance is linked to hepatocarcinogenesis and nonresponsiveness to therapy-induced cell death. Recently, we have demonstrated an essential role of the antiapoptotic Bcl-2 family member Myeloid cell leukemia-1 (Mcl-1) in hepatocyte survival. In mice lacking Mcl-1 specifically in hepatocytes (Mcl-1Δhep), spontaneous apoptosis caused severe liver damage. Here, we demonstrate that chronically increased apoptosis of hepatocytes coincides with strong hepatocyte proliferation resulting in hepatocellular carcinoma (HCC).…
Genetic association of autoimmune hepatitis and human leucocyte antigen in German patients
To report on our large German collective and updated data of 142 patients with autoimmune hepatitis (AIH) type 1.Key investigations performed were liver biopsy, serum autoantibodies as well as serum markers such as IgG and elevated transaminases. Antinuclear antigen (ANA) and smooth muscle antigen (SMA) autoantibodies characterized type 1 AIH. Type 3 (AIH) was solely characterized by the occurrence of soluble liver antigen/liver-pancreas antigen (SLA/LP) autoantibodies either with or without ANA or SMA autoantibodies.Most prevalent HLAs were A2 (68 patients, 48%), B8 (63 patients, 44%), C7 (90 patients, 63%), DR3 (49 patients, 38%), DR4 (49 patients, 38%) and DQ2 (42 patients, 30%). Compare…
Predicting the outcome of patients with hepatocellular carcinoma treated with immunotherapy - the CRAFITY score
Liver-specific Ldb1 deletion results in enhanced liver cancer development.
Background & Aims LIM-domain-binding (Ldb) proteins have been demonstrated to be essential not only to key embryonic developmental processes but also to carcinogenesis. We have previously demonstrated Ldb1 to be of high biological and developmental relevance, as a targeted deletion of the Ldb1 gene in mice results in an embryonic lethal and pleiotropic phenotype. Methods We have now established a liver-specific Ldb1 knock out to investigate the role of Ldb1 in carcinogenesis, in particular in hepatocellular carcinoma (HCC) development, in vivo . Results These mice demonstrated a significantly enhanced growth of liver cancer by means of tumor size and number, advocating for an essential role…
LASS6, an additional member of the longevity assurance gene family
Longevity assurance genes (LAGs) represent a subgroup of the homeobox gene family. Five mammalian homologs have been reported, and the corresponding proteins have previously been investigated with respect to their key role in ceramide synthesis. However, members of the LAG family have been shown to be involved in cell growth regulation and cancer differentiation. In an effort to characterize additional members of the LAG family, we have screened the latest releases of genomic databases and report on the bioinformatic characterization of yet another member, LAG1 longevity assurance homolog 6 (LASS6). Like other LAG family members, the LASS6 protein contained a homeodomain and LAG1 domain. In…
Spontaneous hepatic fibrosis in transgenic mice overexpressing PDGF-A.
Platelet derived growth factor (PDGF) plays a central role in repair mechanisms after acute and chronic tissue damage. To further evaluate the role of PDGF-A in liver fibrogenesis in vivo, we generated transgenic mice with hepatocyte-specific overexpression of PDGF-A using the CRP-gene promoter. Transgenic but not wildtype mice showed expression of PDGF-A mRNA in the liver. Hepatic PDGF-A overexpression was accompanied by a significant increase in hepatic procollagen III mRNA expression as well as TGF-beta1 expression. Liver histology showed increased deposition of extracellular matrix in transgenic but not in wildtype mice. PDGF-A-transgenic mice showed positive sinusoidal staining for alp…
CellLineNavigator: a workbench for cancer cell line analysis
The CellLineNavigator database, freely available at http://www.medicalgenomics.org/celllinenavigator, is a web-based workbench for large scale comparisons of a large collection of diverse cell lines. It aims to support experimental design in the fields of genomics, systems biology and translational biomedical research. Currently, this compendium holds genome wide expression profiles of 317 different cancer cell lines, categorized into 57 different pathological states and 28 individual tissues. To enlarge the scope of CellLineNavigator, the database was furthermore closely linked to commonly used bioinformatics databases and knowledge repositories. To ensure easy data access and search abili…
385 MOLECULAR STAGES OF PDGFB DRIVEN LIVER FIBROSIS: LESONS FROM A TRANSGENIC MOUSE MODEL
underlying pathomechanisms is hampered by the lack of a suitable animal model. To circumvent this problem, we studied hepcidinknockout (KO) mice as a model of iron-overload associated liver disease. Methods: 6 and 12 month-old hepcidin-KO and -wild type (WT) mice fed 3% iron carbonyl-containing diet (Fe-diet) since four weeks of age were compared to age-matched WT and KO animals kept on standard diet. The liver phenotype was quantified serologically as well as morphometrically based on hematoxylin & eosin, Prussian blue and Sirius red stainings. Liver iron content was determined by atomic mass absorption. Liver fibrosis development was determined by collagen RT-PCR and hydroxyproline assay.…
Genetics of hepatocellular carcinoma.
The completely assembled human genome has made it possible for modern medicine to step into an era rich in genetic information and high-throughput genomic analysis. These novel and readily available genetic resources and analytical tools may be the key to unravel the molecular basis of hepatocellular carcinoma (HCC). Moreover, since an efficient treatment for this disease is lacking, further understanding of the genetic background of HCC will be crucial in order to develop new therapies aimed at selected targets. We report on the current status and recent developments in HCC genetics. Special emphasis is given to the genetics and regulation of major signalling pathways involved in HCC such …
Novel insights in the genetics of HCC recurrence and advances in transcriptomic data integration.
Background & Aims: In approximately 70% of patients with hepatocellular carcinoma (HCC) treated by resection or ablation, disease recurs within 5 years. Although gene expression signatures have been associated with outcome, there is no method to predict recurrence based on combined clinical, pathology, and genomic data (from tumor and cirrhotic tissue). We evaluated gene expression signatures associated with outcome in a large cohort of patients with early stage (Barcelona-Clinic Liver Cancer 0/A), single-nodule HCC and heterogeneity of signatures within tumor tissues. Methods:We assessed 287 HCC patients undergoing resection and tested genome-wide expression platforms using tumor (n = 287)…
ΔNp73β is oncogenic in hepatocellular carcinoma by blocking apoptosis signaling via death receptors and mitochondria
p73 belongs to the p53 family of transcription factors known to regulate cell cycle and apoptosis. The Trp73 gene has two promoters that drive the expression of two major p73 isoform subfamilies: TA and ΔN. In general, TAp73 isoforms show proapoptotic activities, whereas members of the N-terminally truncated (ΔN) p73 subfamily that lack the transactivation domain show antiapoptotic functions. We found that upregulation of ΔNp73 in hepatocellular carcinoma (HCC) correlated with reduced survival. Here, we investigated the molecular mechanisms accounting for the oncogenic role of ΔNp73 in HCC.ΔNp73β can directly interfere with the transcriptional activation function of the TA (containing the t…
Update on autoimmune hepatitis
Autoimmune hepatitis (AIH) is a necroinflammatory liver disease of unknown etiology that occurs in children and adults of all ages. Characteristics are its autoimmune features, hyperglobulinemia (IgG), and the presence of circulating autoantibodies, as well as a response to immunosuppressant drugs. Current treatment consists of prednisone and azathioprine and in most patients this disease has become very treatable. Over the past 2 years, a couple of new insights into the genetic aspects, clinical course and treatment of AIH have been reported, which will be the focus of this review. In particular, we concentrate on genome-wide microsatellite analysis, a novel mouse model of AIH, the evaluat…
Next generation sequencing of HCC from European and Asian HCC cohorts. Back to p53 and Wnt/β-catenin
Hepatocellular carcinoma (HCC) is the most common pri- mary liver malignancy. Here, we performed high-resolution copy- number analysis on 125 HCC tumors and whole-exome sequencing on 24 of these tumors. We identified 135 homozygous deletions and 994 somatic mutations of genes with predicted functional conse- quences. We found new recurrent alterations in four genes (ARID1A, RPS6KA3, NFE2L2 and IRF2) not previously described in HCC. Func- tional analyses showed tumor suppressor properties for IRF2, whose inactivation, exclusively found in hepatitis B virus (HBV)-related tumors, led to impaired TP53 function. In contrast, inactivation of chromatin remodelers was frequent and predominant in al…
Knockout of myeloid cell leukemia-1 induces liver damage and increases apoptosis susceptibility of murine hepatocytes
Apoptosis, or programmed cell death, regulates tissue development and homeostasis in multi-cellular organisms. Extrinsic or intrinsic death signals activate pro-apoptotic pathways, resulting in the activation of caspases and finally in cell death. An important event during apoptosis process is the permeabilization of the outer mitochondrial membrane (OMM). Integrity of the OMM is regulated by the Bcl-2 protein family, which is divided into three groups: anti-apoptotic members Bcl-2, Bcl-xL and myeloid cell leukemia-1 (Mcl-1), pro-apoptotic multidomain members Bax and Bak, and pro-apoptotic BH3-only proteins. Mitochondrial activation is regulated by selective interactions of Bcl-2 proteins v…
Capecitabine and irinotecan with and without bevacizumab for advanced colorectal cancer patients
AIM: To investigate the efficacy and safety of cape-citabine plus irinotecan ± bevacizumab in advanced or metastatic colorectal cancer patients. METHODS: Forty six patients with previously untreated, locally-advanced or metastatic colorectal cancer (mCRC) were recruited between 2001-2006 in a prospective open-label phase II trial, in German community-based outpatient clinics. Patients received a standard capecitabine plus irinotecan (CAPIRI) or CAPIRI plus bevacizumab (CAPIRI-BEV) regimen every 3 wk. Dose reductions were mandatory from the first cycle in cases of > grade 2 toxicity. The treatment choice of bevacizumab was at the discretion of the physician. The primary endpoints were respon…
CellMinerHCC: a microarray-based expression database for hepatocellular carcinoma cell lines.
Background & Aims Therapeutic options for hepatocellular carcinoma (HCC) still remain limited. Development of gene targeted therapies is a promising option. A better understanding of the underlying molecular biology is gained in in vitro experiments. However, even with targeted manipulation of gene expression varying treatment responses were observed in diverse HCC cell lines. Therefore, information on gene expression profiles of various HCC cell lines may be crucial to experimental designs. To generate a publicly available database containing microarray expression profiles of diverse HCC cell lines. Methods Microarray data were analyzed using an individually scripted R program package. Dat…
Liver specific overexpression of platelet-derived growth factor-B accelerates liver cancer development in chemically induced liver carcinogenesis
A genetic basis of hepatocellular carcinoma (HCC) has been well-established and major signaling pathways, such as p53, Wnt-signaling, transforming growth factor-β (TGF-β) and Ras pathways, have been identified to be essential to HCC development. Lately, the family of platelet-derived growth factors (PDGFs) has shifted to the center of interest. We have reported on spontaneously developing liver fibrosis in PDGF-B transgenic mice. Since HCC rarely occurs in healthy liver, but dramatically increases at the cirrhosis stage of which liver fibrosis is a preliminary stage, we investigated liver cancer development in chemically induced liver carcinogenesis in these mice. HCC induction was performe…
Genome-wide association analysis in primary sclerosing cholangitis identifies two non-HLA susceptibility loci
Primary sclerosing cholangitis (PSC) is a chronic bile duct disease affecting 2.4-7.5% of individuals with inflammatory bowel disease. We performed a genome-wide association analysis of 2,466,182 SNPs in 715 individuals with PSC and 2,962 controls, followed by replication in 1,025 PSC cases and 2,174 controls. We detected non-HLA associations at rs3197999 in MST1 and rs6720394 near BCL2L11 (combined P = 1.1 x 10(-16) and P = 4.1 x 10(-8), respectively).
Sirtuin-6-dependent genetic and epigenetic alterations are associated with poor clinical outcome in hepatocellular carcinoma patients
Sirtuin 6 (SIRT6) is a member of the sirtuin family of NAD+–dependent deacetylases. Genetic deletion of Sirt6 in mice results in a severe degenerative phenotype with impaired liver function and premature death. The role of SIRT6 in development and progression of hepatocellular carcinoma is currently unknown. We first investigated SIRT6 expression in 153 primary human liver cancers and in normal and cirrhotic livers using microarray analysis. SIRT6 was significantly down-regulated in both cirrhotic livers and cancer. A Sirt6 knockout (KO) gene expression signature was generated from primary hepatoctyes isolated from 3-week-old Sirt6-deficient animals. Sirt6-deficient hepatocytes showed up-re…
Microarray-Based Gene Expression Analysis of Hepatocellular Carcinoma
Microarray studies have successfully shed light on various aspects of the molecular mechanisms behind the development of hepatocellular carcinoma (HCC), such as the identification of novel molecular subgroups and the genetic profiles associated with metastasis and venous invasion. These experiments, mainly comprising genome wide profiling, potentially represent the basis of novel targeted therapeutic strategies in HCC. In response, we summarize the multiple reported expression profiles in HCC associated with HCC development, novel subgroups, venous invasion and metastasis.
Pregnancy in primary sclerosing cholangitis
Background There is a paucity of data on fertility or pregnancy in patients with primary sclerosing cholangitis (PSC). Objective To assess fertility in PSC by comparing the number of children in a large cohort of PSC patients to healthy controls and to investigate the outcome of pregnancy, as well as the influence of pregnancy on the disease course. Design Case series. Setting Germany. Participants 229 PSC patients and 569 healthy controls were evaluated for the number of children. 17 patients with PSC and at least one pregnancy, or who received a diagnosis of PSC within 6 months after delivery, were included in the more detailed analysis. Main outcome measures Number of children per patien…
Hepatocellular carcinoma in patients with autoimmune hepatitis.
To evaluate and confirm the low incidence of hepatocellular carcinoma (HCC) in patients with autoimmune hepatitis (AIH). At present only very few cases of HCC in patients with AIH and definite exclusion of chronic viral hepatitis have been published, suggesting that HCC due to AIH is rare.In order to further investigate the incidence of HCC in patients with AIH, we reviewed our large cohort of 278 patients with AIH.Eighty-nine patients (32%) were diagnosed with liver cirrhosis, a preneoplastic condition for HCC. We studied a total of 431 patient years of cirrhosis in these patients, an average 4.8 years per patient. During this period none of the patients of our own study cohort developed H…
1124 FERTILITY AND PREGNANCY IN PRIMARY SCLEROSING CHOLANGITIS
Erarbeitung eines PBC-Therapiepfads für eine integrierte Versorgung in Deutschland
IFN-alpha-induced apoptosis in hepatocellular carcinoma involves promyelocytic leukemia protein and TRAIL independently of p53.
Abstract IFNs are pleiotropic cytokines that have been shown to be important regulators of cell growth. IFN-α has recently been recognized to harbor therapeutic potential in prevention and treatment of hepatocellular carcinoma (HCC). However, HCC cells respond differentially to IFN treatment, the mechanism of which is largely unknown. To address this issue, we analyzed the effect of IFN-α on different liver tumor cell lines. We found that growth inhibiting effects of IFN-α in hepatoma cells require PML-NB induction and, moreover, tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) expression on the mRNA and protein level. RNAi silencing of PML down-regulates TRAIL expression in …
Collecting evidence for a stem cell hypothesis in HCC.
Ever since Ernest McCulloch and James E Till defined essential stem cell properties, the field of stem cell biology has attracted increasing interest.1 Manipulating embryonic stem cells has resulted in advanced genetic technologies such as knock-out and transgenic animals, providing valuable models to study genetic influence on a wide variety of diseases.2 The success in manipulating stem cells and the ability to differentiate them into diverse tissues brought with them countless concepts of utilising stem cells in medicine. The idea of perpetually dividing pluripotent cells, capable of differentiating into nearly every possible cell or tissue type, seems like an inexhaustible resource for …