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ABSTRACT: A pleural effusion containing chylomicrons is termed chylothorax and results from leakage of lymph fluid into the pleural cavity. We report on the case of a 59-year-old woman with severe dyspnea due to a large chylothorax. She was known to have liver cirrhosis but no ascites. There was no history of trauma, cardiac function was normal and thorough diagnostic work-up did not reveal any signs of malignancy. In summary, no other etiology of the chylothorax than portal hypertension could be found. Therapy with diuretics as well as parenteral feeding failed to relieve symptoms. After a transjugular intrahepatic portosystemic shunt (TIPS) had successfully been placed, pleural effusion decreased considerably. Eight months later, TIPS revision had to be performed because of stenosis, resulting in remission from chylothorax. This case shows that even in the absence of ascites, chylothorax might be caused by portal hypertension and that TIPS can be an effective treatment option.
World Journal of Gastroenterology 02/2013; 19(7):1140-2. · 2.47 Impact Factor
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ABSTRACT: It is estimated that 1 million persons in Germany suffer from hepatic cirrhosis, which is the final stage of chronic inflammation of the liver. Cirrhosis has multiple causes, all of which lead to structural changes of the liver and to portal hypertension. The main complications of cirrhosis arise in turn: These include bleeding from collateral veins, ascites, hepatocellular carcinoma, encephalopathy, and infection leading to organ failure.
We present the treatment of the main complications of liver cirrhosis with reference to the relevant literature (phase II and III trials, meta-analyses, and reviews).
Endoscopic treatment (ligation) is used for the primary and secondary prophylaxis of variceal bleeding. Drugs to lower portal pressure (e.g., beta-blockers) are an established means of preventing initial or recurrent variceal bleeding over the long term. Vasoconstrictors such as terlipressin are mainly used to treat acute hemorrhage and type 1 hepatorenal syndrome. The main treatment of ascites is with spironolactone, in combination with a loop diuretic where indicated. A shunt (TIPS) is used to treat severe or repeat variceal hemorrhage or refractory ascites. Antibiotics play a well-established role in the treatment of acute hemorrhage, in the treatment and prevention of spontaneous bacterial peritonitis, and in the treatment of encephalopathy. The treatment of hepatocellular carcinoma depends on its extent of spread and on the degree of decompensation of cirrhosis.
For most of the main complications of liver cirrhosis, there are treatments that have been well-tested in randomized trials. Liver transplantation should also be considered in every case.
02/2013; 110(8):126-32. · 2.92 Impact Factor
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Maria A González-Carmona,
Maria Quasdorff,
Annabelle Vogt,
Anja Tamke,
Yildiz Yildiz,
Per Hoffmann,
Thomas Lehmann,
Ralf Bartenschlager,
Joachim W Engels,
Gerd A Kullak-Ublick, Tilman Sauerbruch,
Wolfgang H Caselmann
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ABSTRACT: BACKGROUND: The 5'-noncoding region (5'NCR) of the HCV-genome comprises an internal ribosome entry site essential for HCV-translation/replication. Phosphorothioate oligodeoxynucleotides (tS-ODN) complementary to this region can inhibit HCV-translation in vitro. In this study, bile acid conjugated tS-ODN were generated to increase cell-selective inhibition of 5'NCR-dependent HCV-translation. METHODS: Different bile acid conjugated tS-ODN complementary to the HCV5'NCR were selected for their inhibitory potential in an in vitro transcription/translation assay. To analyze OATP (organic anion transporting polypeptides)-selective uptake of bile acid conjugated ODN, different hepatoma cells were stably transfected with the OATP1B1-transporter and primary human hepatocytes were used. An adenovirus encoding the HCV5'NCR fused to the luciferase gene (Ad-GFP-NCRluc) was generated to quantify 5'NCR-dependent HCV gene expression in OATP-overexpressing hepatoma cells andin vivo. RESULTS: A 17mer phosphorothioate modified ODN (tS-ODN4_13) complementary to HCV5'NCR was able to inhibit 5'NCR-dependent HCV-translation in an in vitro transcription/translation test system by more than 90% and it was also effective in Huh7-cells containing the HCV subgenomic replicon. Conjugation to taurocholate (tS-ODN4_13T) significantly increased selective ODN uptake by primary human hepatocytes and by OATP1B1-expressing HepG2-cells compared to parental HepG2-cells. Correspondingly, tS-ODN4_13T significantly inhibited HCV gene expression in liver-derived OATP1B1-expressing HepG2- or CCL13-cells up to 70% compared to unconjugated tS-ODN and compared to mismatch taurocholate coupled tS-ODN. In vivo, tS-ODN4_13T showed also a trend to block 5'NCR-dependent HCV gene expression. CONCLUSIONS: The tested taurocholate conjugated 17mer antisense ODN complementary to HCV5'NCV showed an increased and selective uptake by hepatocytes and liver-derived cells through OATP-mediated transport resulting in enhanced specific inhibition of HCV gene expression in vitro and in vivo. Thus, this novel approach may represent a promising strategy to improve antisense approaches with ODN in the control of hepatitis C infection.
Antiviral research 11/2012; · 3.61 Impact Factor
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ABSTRACT: BACKGROUND/AIMS: The noninvasive measurement of liver stiffness using transient elastography (TE) is increasingly being used alongside liver biopsy. However, several conditions may lead to higher liver stiffness values without reflecting more fibrosis. Such conditions (e.g. hepatitis, cholestasis, heart failure, mechanical ventilation) limit the interpretation of liver stiffness measurements. The influence of hemodialysis on the measurement of liver stiffness has not been investigated to date. Here, we analyzed liver stiffness assessed by fibroscan in 17 patients directly before and after a hemodialysis session. PATIENTS AND METHODS: Measurement of hepatic stiffness by TE was carried out using the Fibroscan device with the 'M probe' directly before and directly after one session of hemodialysis. Each measurement consisted of at least 10 individual and valid measurements, with a success rate of at least 60%, and an interquartile range of less than 25%. All measurements were carried out by one investigator not involved in patient management. RESULTS: Before dialysis, the median TE was 5.1 kPa (2.8-17 kPa). Ten patients had values below the threshold of 7.1 kPa and seven patients had TE>7.1 kPa. The median net fluid withdrawal by hemodialysis was 2.5 l (0.4-3.1 l) and did not differ between patients. After dialysis, the TE median was 7.4 kPa (3.5-12.5 kPa) and had changed in all patients except one. Liver stiffness increased significantly when the initial TE was lower than 7.1 kPa (P=0.05), but not when the initial TE was higher than 7.1 kPa. Furthermore, the magnitude of the change in TE after hemodialysis correlated inversely with the liver stiffness before hemodialysis (P=0.03) and with spleen length measured by ultrasound (P=0.03). CONCLUSION: This study is the first to report on the influence of hemodialysis on liver stiffness measurement. In contrast to previous reports, liver stiffness might increase after fluid withdrawal if patients do not show significant fibrosis. We conclude that before dialysis, TE possibly better differentiates between patients with or without significant fibrosis.
European journal of gastroenterology & hepatology 10/2012; · 1.66 Impact Factor
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Jonel Trebicka,
Evrim Anadol,
Natalia Elfimova,
Ingo Strack,
Michael Roggendorf,
Sergei Viazov,
Inga Wedemeyer,
Uta Drebber,
Jürgen Rockstroh, Tilman Sauerbruch,
Hans-Peter Dienes,
Margarete Odenthal
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ABSTRACT: BACKGROUND/AIMS: The progression of liver fibrosis in patients with chronic hepatitis C (CHC) is important in deciding on the treatment of the virus. As liver biopsy and liver stiffness measurement for staging of fibrosis present limitations, circulating levels of miR-122 have been suggested as a novel biomarker to predict the extent of liver injury. We evaluated the potential of miR-122 as an indicator of fibrosis progression in CHC infection and performed for the first time a comprehensive analysis of hepatic and circulating miR-122 levels in patients with CHC. METHODS: Patients with well-documented CHC infection were selected from the database of HepNet, the German-Competence-Network on Viral Hepatitis. All patients underwent blood sampling and liver biopsy with grading of inflammation and staging of fibrosis. RNA was extracted from 84 liver biopsies and 167 serum samples of CHC patients. miR-122 levels in liver and serum samples were quantified by Real Time PCR normalized by RNU6 or spiked-in RNA, respectively. RESULTS: Hepatic levels of miR-122 decreased significantly with the severity of fibrosis (p=0.001). In addition, circulating miR-122 levels correlated negatively with increasing stages of fibrosis, although inverse correlation was moderate due to a two-phase miR-122 pattern during fibrosis progression. Thus, circulating miR-122 levels decreased in patients with severe fibrosis (F3, F4), while in early stages with distinct fibrotic structures (F2) and high inflammatory activity, miR-122 serum levels were elevated. CONCLUSIONS: We conclude that during progression of fibrosis less miR-122 is released into the blood stream due to the loss of liver cells and to the decrease of hepatic miR-122 levels. Although the release of circulating miR-122 possibly mirrors acute liver injury, in chronic liver disease and fibrosis, the loss of liver cells and decreased hepatocellular miR-122 expression render miR-122 an inappropriate marker when exclusively used for interpretation of fibrosis progression.
Journal of Hepatology 10/2012; · 9.26 Impact Factor
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Sabine Klein,
Jeremias Klösel,
Robert Schierwagen,
Christian Körner,
Michaela Granzow,
Sebastian Huss,
Irela Gretchen Reza Mazar,
Susanne Weber,
Peter F M van den Ven,
Ursula Pieper-Fürst,
Dieter O Fürst,
Jacob Nattermann,
Frank Lammert, Tilman Sauerbruch,
Jonel Trebicka
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ABSTRACT: Hepatic myofibroblasts (MFB) show increased proliferation, migration and collagen production, which are crucial for hepatic fibrogenesis. Atorvastatin treatment inhibits proliferation, apoptosis and cytokine production of MFB in bile duct-ligated (BDL) rats in vivo. Here, we have further investigated the underlying mechanisms. Primary rat hepatic stellate cells (HSC) were isolated and culture-activated to hepatic MFB. Following 3 days of incubation with atorvastatin (10(-4), 10(-5) and 10(-6) M), transcription levels of profibrotic cytokines (transforming growth factor-β1, connective tissue growth factor and TIMP1) and procollagen Ia were analyzed by real time PCR. Proliferation was investigated by 5'-bromo-2'-deoxyuridine assays. α-Smooth muscle actin protein expression was examined by western blotting. Fluorescence-activated cell sorting analysis of Annexin V and propidium iodide were used to measure apoptosis. Furthermore, p21 western blotting and β-galactosidase staining were investigated in MFB as senescence markers. Subsequently, hepatic expression of desmin and senescence markers were analyzed in the livers of rats receiving atorvastatin (15 mg/kg*d) for 1 week starting 3 and 5 weeks after BDL. Atorvastatin inhibited the activation of HSC to MFB and decreased cytokine and collagen production in MFB in vitro. In addition, proliferation, cytokine and collagen production of MFB were reduced by atorvastatin. Atorvastatin initiated apoptosis at 10(-4) M and attenuated it at 10(-5) M. Atorvastatin induced p21 protein expression and β-galactosidase staining of MFB in vitro and in vivo. Atorvastatin elicits similiar effects on MFB as previously seen in vivo: it decreases MFB turnover and fibrogenesis. We suggest that a further mechanism explaining these effects is senescence of cells.
Laboratory Investigation 08/2012; 92(10):1440-50. · 3.64 Impact Factor
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Sabine Klein,
Marike Marjolijn Van Beuge,
Michaela Granzow,
Leonie Beljaars,
Robert Schierwagen,
Sibel Kilic,
Iren Heidari,
Sebastian Huss, Tilman Sauerbruch,
Klaas Poelstra,
Jonel Trebicka
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ABSTRACT: BACKGROUND & AIMS: Rho-kinase activation mediates cell contraction and increases intrahepatic resistance and consequently portal pressure in liver cirrhosis. Systemic Rho-kinase inhibition decreases portal pressure in cirrhosis, but also arterial pressure. Thus, liver-specific Rho-kinase inhibition is needed. The delivery of Rho-kinase inhibitor to activated hepatic stellate cells reduces fibrosis. It might also relax these contractile cells and therewith decrease intrahepatic resistance. We tested this hypothesis by performing acute experiments in cirrhotic rats. METHODS: Cirrhosis models were CCl(4)-intoxication and bile duct ligation. Three hours after injection of the Rho-kinase inhibitor (Y26732) coupled with a carrier (mannose-6-phosphate modified human serum albumin), which targets activated hepatic stellate cells, hemodynamics were analyzed by the colored microsphere technique and direct pressure measurements. The delivery site and effect of Rho-kinase inhibitor were investigated by immunohistochemical stainings, as well as Western blot. Experiments with Rho-kinase inhibitor coupled with unmodified human serum albumin served as untargeted control. RESULTS: In both models of cirrhosis, the carrier coupled Rho-kinase inhibitor lowered the portal pressure and decreased the hepatic-portal resistance. Immunohistochemical desmin-staining showed the carrier in hepatic stellate cells. The targeted therapy decreased the expression of the phosphorylated substrate of Rho-kinase (moesin) and abolished myosin light chains phosphorylation in fibrotic septae (collagen-staining). The targeted Rho-kinase inhibitor showed no major extrahepatic effects. By contrast, the untargeted Rho-kinase inhibitor elicited severe systemic hypotension. CONCLUSIONS: Activated hepatic stellate cells are crucially involved in portal hypertension in cirrhosis. Targeting of Rho-kinase in hepatic stellate cells not only decreased fibrosis, as previously shown, but also lowers portal pressure acutely without major systemic effects as demonstrated in this study.
Journal of Hepatology 08/2012; · 9.26 Impact Factor
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ABSTRACT: Micro-RNAs (miRNAs) are small, non-coding RNA species considered to fine-tune basic cellular functions by modulating target gene translation and/or mRNA stability. A common G/C polymorphism (rs2910164) in the precursor (pre-) miR-146a gene engaged in NF-κB signaling and apoptosis pathways has been reported to modulate the genetic risk of hepatocellular carcinoma by increased G-allelic production of mature miR-146a. We investigated rs2910164 in a large European-based cholangiocarcinoma (CCA) cohort.
We recruited 182 CCA patients and 350 controls in three academic medical centers. Genotyping for rs2910164 was performed by PCR-based assays with 5'-nuclease and fluorescence detection. Genotype frequencies were tested for consistency with the Hardy-Weinberg equilibrium using an exact test; allelic and genotypic differences between the patients and controls were assessed by the Chi-square test and Armitage's trend test. Exploratory subgroup analyses included gender, tumor localization (extra- versus intrahepatic CCA) and early-onset CCA.
Genotype distributions were consistent with the Hardy-Weinberg equilibrium. No significant differences in either allele or genotype distributions were detected between the CCA and control groups or the respective subgroups investigated. However, there was a trend for a protective effect of the heterozygous single-nucleotide polymorphism state GC, as indicated by an underrepresentation in the CCA group in general (29% vs 35%; P=0.18) and, in particular, for extrahepatic tumor sites (26% vs 35%; OR=0.67; 95% CI, 0.43-1.02; P=0.065).
Our data do not support a prominent contribution of the pre-miR-146a sequence variant in the genetic predisposition to CCA. However, current studies functionally characterizing rs2910164 have proposed that distinct repertoires of target genes are addressed by genotype-specific mature miR-146a species. Given the detected trend towards a potentially protective role of GC heterozygosity, a subtle modulation of genetic CCA risk by the pre-miR-146a GC genotype may exist and should be evaluated further.
Hepatobiliary & pancreatic diseases international: HBPD INT 08/2012; 11(4):412-7. · 1.08 Impact Factor
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ABSTRACT: Glycolipids have been shown to serve specialized functions in cell signalling, proliferation and differentiation processes, which are all important during liver regeneration. We previously generated beta-glucosidase 2 (GBA2) knockout mice that accumulate the glycolipid glucosylceramide in various tissues, including the liver. The present study addressed the role of GBA2-deficiency and subsequent glucosylceramide accumulation in liver regeneration.
Gba2 knockout and wild-type mice were subjected to two-third partial hepatectomy. Mice were sacrificed at different time points, blood was collected, and the remnant liver was removed. Glucosylceramide and ceramide were quantified using mass spectrometry from whole liver and isolated hepatocytes. Serum and hepatocytic supernatant of IL-6, TNF-α and TGF-β levels were measured using ELISA. Cell signalling proteins were analysed using immunoblots.
Regenerating liver after partial hepatectomy showed a significant increase of hepatic glucosylceramide in GBA2-deficient mice compared to controls. Accumulation of glucosylceramide was associated with a delay in liver regeneration and reduced serum levels of IL-6 and TNF-α. Furthermore, reduced IL-6 led to decreased expression of the phosphorylated form of the signal transducer and activator of transcription 3 (P-STAT3).
We conclude that increased glucosylceramide affects cytokine- and growth factor-mediated signalling pathways during liver regeneration. Thus, the repression of IL-6/STAT3 signalling pathway seems to be one of the mechanisms for the delay of liver regeneration in GBA2-deficient mice.
Liver international: official journal of the International Association for the Study of the Liver 07/2012; 32(9):1354-62. · 3.82 Impact Factor
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ABSTRACT: Recently, genome-wide studies identified genetic variants that affect serum 25-hydroxyvitamin D levels in healthy populations (rs12785878, near dehydrocholesterol reductase, DHCR7; rs10741657, at CYP2R1; and rs7041, at vitamin D binding protein, GC). Because vitamin D deficiency is associated with advanced liver disease, we hypothesized that these variants are associated with 25(OH)-vitamin D levels and liver fibrosis. Overall, 712 Caucasian patients with chronic liver diseases were included. Liver fibrosis was assessed by transient elastography (TE) and/or histology. Serum levels of 25(OH)-vitamin D were correlated with TE and fibrosis stages. Genotypes were determined using TaqMan assays and tested for association with vitamin D and liver stiffness. Serum 25(OH)-vitamin D levels were inversely correlated with liver stiffness and histology (P < 0.001). Homozygous carriers of the rare DHCR7 allele or the common CYP2R1 allele presented with reduced 25(OH)-vitamin D levels (P < 0.05). The variant rs12785878 in the DHCR7 locus was associated with liver stiffness in both patients with TE <7.0 kPa and TE between 7.0 and 9.5 kPa. 25(OH)-vitamin D levels correlated with sunshine hours at the time of inclusion (P < 0.001). Conclusion: Common variation in 25(OH)-vitamin D metabolism is associated with liver stiffness in patients presenting with low to moderately increased elasticity. Although the susceptible DHCR7 genotype confers small risk, we speculate that the observed stiffness differences indicate a stronger influence of 25(OH)-vitamin D on initiation rather than progression of hepatic fibrosis. (HEPATOLOGY 2012).
Hepatology 05/2012; · 11.66 Impact Factor
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ABSTRACT: Natural killer (NK) cells play a role in the early control and natural course of hepatitis C virus (HCV) infection. NK cell function is regulated by a multitude of receptors, including activating NKp46 receptor. However, reports on NKp46 in hepatitis C are controversial. Therefore, we investigated the hepatic recruitment and function of NKp46(+) NK cells, considering differential surface expression of NKp46 resulting in NKp46(High) and NKp46(Dim) subsets. Intra- and extrahepatic NK-cell subsets from HCV-infected patients were characterized by flow cytometry. Cytotoxic activity and interferon-gamma (IFN-γ) secretion were studied using K-562, P815, and primary hepatic stellate cells as targets. Anti-HCV activity of NK-cell subsets was studied using the replicon system. Density of NKp46 surface expression clearly segregated NKp46(Dim) and NKp46(High) subsets, which differed significantly with respect to the coexpression of maturation markers and NK-cell receptors. More important, NKp46(High) NK cells showed a higher cytolytic activity and stronger IFN-γ secretion than NKp46(Dim) NK cells. Accordingly, NKp46(High) NK cells efficiently blocked HCV replication in vitro. Blocking experiments confirmed an important role for the NKp46 receptor. Furthermore, we found an intrahepatic accumulation of NKp46(High) NK cells. Of note, high cytolytic activity of NKp46(High) NK cells was also confirmed in the intrahepatic NK-cell population, and the frequency of intrahepatic NKp46(High) NK cells was inversely correlated with HCV-RNA levels and fibrosis stage. Conclusions: NKp46(High) expression defines a specific NK-cell subset that may be involved in both the suppression of HCV replication and HCV-associated liver damage underpinning the role of NK cells in the immunopathogenesis of HCV. (HEPATOLOGY 2012).
Hepatology 04/2012; 56(4):1201-13. · 11.66 Impact Factor
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ABSTRACT: Fallbeschreibung:
Eine 25-jährige, hypertone Patientin stellte sich mit seit 10 Tagen bestehenden und zunehmenden diffusen Schmerzen und Obstipation
im Notfallzentrum vor. Sie war zuvor mehrfach ärztlich gesehen worden, ohne dass verschiedenste Analgetika sowie Metoclopramid
zu einer Besserung geführt hatten. Laborchemisch fand sich eine Hyponatriämie. Ein Megakolon und eine Polyneuropathie wurden
festgestellt, kurz nach Aufnahme kam es allerdings bei weiter zunehmender Hyponatriämie im Sinne eines SIADH (Syndrom der
inadäquaten ADH-Sekretion) zu einem generalisierten Krampfanfall. Passend zur Klinik konnte im Urin eine massiv erhöhte Ausscheidung
von Porphyrinen gemessen werden und damit, zusammen mit der deutlich erniedrigten Porphobilinogen-Desaminase-Aktivität, die
Diagnose einer akuten intermittierenden Porphyrie gestellt werden.
Schlussfolgerung:
Der Fall illustriert, wie die Diagnose dieses Krankheitsbildes aufgrund seiner Seltenheit und unspezifischen Symptome leicht
verschleppt wird, wobei die Gefahr besteht, durch Verordnung von auslösenden Medikamenten die Beschwerden noch zu verschlimmern.
Case Report:
A 25-year-old hypertensive patient presented to the Emergency Department with constipation and diffuse pain which had been
increasing for 10 days. She had consulted several doctors before, but neither various analgesics nor metoclopramide had been
beneficial. Blood analysis showed hyponatremia. A megacolon and polyneuropathy were found. Shortly after admission, she developed
generalized seizures while hyponatremia increased compatible with SIADH (syndrome of inadequate ADH secretion). Urine examination
revealed a markedly elevated excretion of porphyrins. Since porphobilinogen deaminase activity was clearly decreased, diagnosis
of acute intermittent porphyria could be confirmed.
Conclusion:
This case shows how definite diagnosis of this illness is often delayed because of its rarity and the variety of its possible
symptoms and signs. This delay leads to a high risk of aggravating the disease by prescribing porphyrinogenic drugs.
Schlüsselwörter:
Akute Porphyrie-Hyponatriämie-Megakolon-Krampfanfall
Key Words:
Acute porphyria-Hyponatremia-Megacolon-Seizure
04/2012; 105(4):267-272.
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ABSTRACT: Angiostatin and angiostatin-like molecules are known as anti-angiogenic factors, which inhibit endothelial cell functions resulting in reduced tumour growth. Recent data indicate that these molecules, especially PlgK1-5, directly affect tumour cells, which could explain the strong anti-tumoural effects of PlgK1-5. Therefore, we have analysed whether PlgK1-5 alters tumour cell functions and expression levels of cell adhesion molecules in murine and human hepatoma cells in vitro and in vivo.
First, effects on tumour growth, proliferation and apoptosis were investigated in vivo in a subcutaneous tumour model. In vitro, effects of PlgK1-5 on tumour cell apoptosis, clonal expansion, migration, corresponding ICAM expression and intracellular signal transduction in murine Hepa129 and human HuH7 hepatoma cells have been analysed.
In vivo, subcutaneous tumour growth was reduced by 75% in PlgK1-5-treated animals compared to the controls. This was accompanied by increased tumour cell apoptosis (up to 33%) and decreased tumour cell proliferation (by up to 21%). In vitro, PlgK1-5 induced apoptosis in hepatoma cells, corresponding to increased caspase-8 cleavage and reduced AKT phosphorylation. Migration and clonal expansion was also diminished in PlgK1-5-treated Hepa129, corresponding to decreased ICAM expression levels.
Here, we show that PlgK1-5 directly affects tumour cells by decreasing cell adhesion resulting-at least partly-in apoptosis. This is mediated by altered intracellular signal transduction and by activation of the caspase cascade. These findings further underscore the potential therapeutic role of PlgK1-5 in the treatment of HCC.
International Journal of Colorectal Disease 03/2012; 27(8):1029-38. · 2.38 Impact Factor
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ABSTRACT: In mouse models it has been shown that natural killer (NK) cells can attenuate liver fibrosis via killing of activated hepatic stellate cells (HSCs) in a NKG2D- and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-dependent manner. However, only little data exist regarding interactions of human NK cells with HSCs and their potential role in hepatitis C virus (HCV)-associated fibrogenesis. Therefore, purified NK cells from untreated HCV RNA(+) patients (n=33), interferon-α (IFN-α)-treated patients (n=17) and healthy controls (n=18) were coincubated with activated primary HSCs, and were tested for degranulation (CD107a expression) and secretion of IFN-γ and TNF-α, respectively. Induction of HSC apoptosis was analyzed using an active caspase-3 assay. We found that following coincubation with HSCs a significant increase in CD107a expression could be observed in both NK cells from HCV(+) patients and healthy controls, whereas only negligible secretion of IFN-γ and TNF-α could be detected. More importantly, NK cells from untreated HCV RNA(+) patients were significantly more effective in induction of HSC apoptosis (17.8 ± 9.2%) than NK cells from healthy controls (6.2 ± 2.1%; P<0.0001). Additionally, we observed an inverse correlation of liver fibrosis stage and the ability of NK cells to induce HSC apoptosis. Induction of HSC apoptosis was contact dependent and could partly be blocked by antibodies specific for TRAIL, NKG2D and FasL, respectively. It is noteworthy that NK cells from IFN-α-treated HCV(+) patients displayed the highest capability to kill HSCs (27.6 ± 10.5%). Accordingly, pre-stimulation of NK cells with recombinant IFN-α significantly increased the ability of NK cells to induce cell death in primary HSCs and was dependent on upregulated expression of TRAIL. Here we demonstrate that NK cells from HCV-infected patients are highly efficient in inducing apoptosis of activated HSCs. Thus, NK cells may have an important anti-fibrotic role in chronic hepatitis C.
Laboratory Investigation 03/2012; 92(7):967-77. · 3.64 Impact Factor
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Christian Körner,
Katarina Riesner,
Benjamin Krämer,
Marianne Eisenhardt,
Andreas Glässner,
Franziska Wolter,
Thomas Berg,
Tobias Müller, Tilman Sauerbruch,
Jacob Nattermann,
Ulrich Spengler,
Hans Dieter Nischalke
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ABSTRACT: Tumour surveillance via induction of TRAIL-mediated apoptosis is a key mechanism, how the immune system prevents malignancy. To determine if gene variants in the TRAIL receptor I (DR4) gene affect the risk of hepatitis C virus (HCV)-induced liver cancer (HCC), we analysed DR4 mutations C626G (rs20575) and A683C (rs20576) in HCV-infected patients with and without HCC.
Frequencies of DR4 gene polymorphisms were determined by LightSNiP assays in 159 and 234 HCV-infected patients with HCC and without HCC, respectively. 359 healthy controls served as reference population.
Distribution of C626G and A683C genotypes were not significantly different between healthy controls and HCV-positive patients without HCC. DR4 variants 626C and 683A occurred at increased frequencies in patients with HCC. The risk of HCC was linked to carriage of the 626C allele and the homozygous 683AA genotype, and the simultaneous presence of the two risk variants was confirmed as independent HCC risk factor by Cox regression analysis (Odds ratio 1.975, 95% CI 1.205-3.236; p = 0.007). Furthermore HCV viral loads were significantly increased in patients who simultaneously carried both genetic risk factors (2.69 ± 0.36 × 10(6) IU/ml vs. 1.81 ± 0.23 × 10(6) IU/ml, p = 0.049).
The increased prevalence of patients with a 626C allele and the homozygous 683AA genotype in HCV-infected patients with HCC suggests that these genetic variants are a risk factor for HCC in chronic hepatitis C.
BMC Cancer 03/2012; 12:85. · 3.01 Impact Factor
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Alexandra Wojtalla,
Frank Herweck,
Michaela Granzow,
Sabine Klein,
Jonel Trebicka,
Sebastian Huss,
Raissa Lerner,
Beat Lutz,
Frank Alexander Schildberg,
Percy Alexander Knolle, Tilman Sauerbruch,
Manfred Vincenz Singer,
Andreas Zimmer,
Sören Volker Siegmund
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ABSTRACT: The endocannabinoid system is a crucial regulator of hepatic fibrogenesis. We have previously shown that the endocannabinoid anandamide (AEA) is a lipid mediator that blocks proliferation and induces death in hepatic stellate cells (HSCs), the main fibrogenic cell type in the liver, but not in hepatocytes. However, the effects of other endocannabinoids such as N-arachidonoyl dopamine (NADA) have not yet been investigated. The NADA-synthesizing enzyme tyrosine hydroxylase was mainly expressed in sympathetic neurons in portal tracts. Its expression pattern stayed unchanged in normal or fibrotic liver. NADA dose dependently induced cell death in culture-activated primary murine or human HSCs after 2-4 h, starting from 5 μM. Despite caspase 3 cleavage, NADA-mediated cell death showed typical features of necrosis, including ATP depletion. Although the cannabinoid receptors CB1, CB2, or transient receptor potential cation channel subfamily V, member 1 were expressed in HSCs, their pharmacological or genetic blockade failed to inhibit NADA-mediated death, indicating a cannabinoid-receptor-independent mechanism. Interestingly, membrane cholesterol depletion with methyl-β-cyclodextrin inhibited AEA- but not NADA-induced death. NADA significantly induced reactive oxygen species formation in HSCs. The antioxidant glutathione (GSH) significantly decreased NADA-induced cell death. Similar to AEA, primary hepatocytes were highly resistant against NADA-induced death. Resistance to NADA in hepatocytes was due to high levels of GSH, since GSH depletion significantly increased NADA-induced death. Moreover, high expression of the AEA-degrading enzyme fatty acid amide hydrolase (FAAH) in hepatocytes also conferred resistance towards NADA-induced death, since pharmacological or genetic FAAH inhibition significantly augmented hepatocyte death. Thus the selective induction of cell death in HSCs proposes NADA as a novel antifibrogenic mediator.
AJP Gastrointestinal and Liver Physiology 02/2012; 302(8):G873-87. · 3.43 Impact Factor
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Liver international: official journal of the International Association for the Study of the Liver 02/2012; 32(2):177-8. · 3.82 Impact Factor
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ABSTRACT: In mouse models, natural killer (NK) cells have been shown to exert anti-fibrotic activity via killing of activated hepatic stellate cells (HSC). Chemokines and chemokine receptors critically modulate hepatic recruitment of NK cells. In hepatitis C, the chemokine receptor CXCR3 and its ligands have been shown to be associated with stage of fibrosis suggesting a role of these chemokines in HCV associated liver damage by yet incompletely understood mechanisms. Here, we analyzed phenotype and function of CXCR3 expressing NK cells in chronic hepatitis C.
Circulating NK cells from HCV-infected patients (n = 57) and healthy controls (n = 27) were analyzed with respect to CXCR3 and co-expression of different maturation markers. Degranulation and interferon-γ secretion of CXCR3(+) and CXCR3(-) NK cell subsets were studied after co-incubation with primary human hepatic stellate cells (HSC). In addition, intra-hepatic frequency of CXCR3(+) NK cells was correlated with stage of liver fibrosis (n = 15).
We show that distinct NK cell subsets can be distinguished based on CXCR3 surface expression. In healthy controls CXCR3(+)CD56Bright NK cells displayed strongest activity against HSC. Chronic hepatitis C was associated with a significantly increased frequency of CXCR3(+)CD56Bright NK cells which showed impaired degranulation and impaired IFN-γ secretion in response to HSC. Of note, we observed intra-hepatic accumulation of this NK cell subset in advanced stages of liver fibrosis.
We show that distinct NK cell subsets can be distinguished based on CXCR3 surface expression. Intra-hepatic accumulation of the functionally impaired CXCR3(+)CD56Bright NK cell subset might be involved in HCV-induced liver fibrosis.
PLoS ONE 01/2012; 7(7):e38846. · 4.09 Impact Factor
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ABSTRACT: Ribavirin improves outcomes of therapy in chronic hepatitis C but its mode of action has still remained unclear. Since ribavirin has been proposed to modulate the host's T cell responses, we studied its direct effects on CD4(+) T cell clones with diverse functional polarization which had been generated from patients with chronic hepatitis C. We analysed in vitro proliferation ([(3)H] thymidine uptake) and cytokine responses (IL-10, IFN-gamma) at varying concentrations of ribavirin (0-10 µg/ml) in 8, 9 and 7 CD4(+) TH1, TH2 and regulatory T cell (Treg) clones, respectively. In co-culture experiments, we further determined effects of ribarivin on inhibition of TH1 and TH2 effector cells by Treg clones. All clones had been generated from peripheral blood of patients with chronic hepatitis C in the presence of HCV core protein. Ribavirin enhanced proliferation of T effector cells and increased production of IFN-gamma in TH1 clones, but had only little effect on IL-10 secretion in TH2 clones. However, ribavirin markedly inhibited IL-10 release in Treg clones in a dose dependent fashion. These Treg clones suppressed proliferation of T effector clones by their IL-10 secretion, and in co-culture assays ribavirin reversed Treg-mediated suppression of T effector cells. Our in vitro data suggest that--in addition to its immunostimulatory effects on TH1 cells--ribavirin can inhibit functions of HCV-specific Tregs and thus reverses Treg-mediated suppression of T effector cells in chronic hepatitis C.
PLoS ONE 01/2012; 7(7):e42094. · 4.09 Impact Factor
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ABSTRACT: It is a challenging task to distinguish between benign and malignant lesions in patients with biliary strictures. Here we analyze whether determination of target gene mRNA levels in intraductal brush cytology specimens may be used to improve the diagnosis of bile duct carcinoma.
Brush cytology specimens from 119 patients with biliary strictures (malignant: n = 72; benign: n = 47) were analyzed in a retrospective cohort study. mRNA of IGF-II mRNA-binding protein 3 (IGF2BP3), homeobox B7 (HOXB7), Forkhead box M1 (FOXM1), kinesin family member 2C (KIF2C) and serine/threonine kinase NEK2 was determined by semi-quantitative RT-PCR using the ΔCt method.
IGF2BP3 (p<0.0001), HOXB7 (p<0.0001), and NEK2 (p<0.0001) mRNA expression levels were significantly increased in patients with cholangiocarcinoma or pancreatic cancer. Median ΔCt values differed by 3.5 cycles (IGF2BP3), 2.8 cycles (HOXB7) and 1.3 cycles (NEK2) corresponding to 11-fold, 7-fold and 2.5-fold increased mRNA levels in malignant versus benign samples. Sensitivity to detect biliary cancer was 76.4% for IGF2BP3 (80.9% specificity); 72.2% for HOXB7 (78.7% specificity) and 65.3% for NEK2 (72.3% specificity), whereas routine cytology reached only 43.1% sensitivity (85.4% specificity). Diagnostic precision was further improved, when all three molecular markers were assessed in combination (77.8% sensitivity, 87.2% specificity) and achieved 87.5% sensitivity and 87.2% specificity when molecular markers were combined with routine cytology.
Our data suggest that measuring IGF2BP3, HOXB7 and NEK2 mRNA levels by RT-PCR in addition to cytology has the potential to improve detection of malignant biliary disorders from brush cytology specimens.
PLoS ONE 01/2012; 7(8):e42141. · 4.09 Impact Factor
