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Background/aims: Results of our previous studies supported the concept that in the human liver, the smallest ramification of the biliary tree, the bile ductules, might contain hepatic progenitor cells. An insufficient proliferative response and loss of bile ductules preceded bile duct loss whereas preservation of bile ductules mitigated bile duct loss., Methods: Presently we investigated the vascular profile of the bile ductules in diseased human livers and livers showing normal histological features as controls, using CD34, CK7 and alphaSMA antibodies in a double immunolabeling technique. VEGF-A expression was also studied. In control livers bile ductules traversed the boundaries of the portal tract into the lobule as ductular-vascular units, in a pattern outlining the classic hexagonal lobule, following the vascular septa. The latter are thought to be extensions of portal veins. In diseased states the two structures reacted in unison. Increased or decreased numbers of ductules were consistently accompanied by similar changes of accompanying microvessels. Increased numbers of ductules and microvessels were paralleled by increased ductular expression of VEGF-A., Results: Our data support the concept that the smallest branches of the biliary tree might have their own vascular supply and that the ductules might in turn maintain their vasculature during regenerative processes.

Background and Purpose: Liver fibrosis is a major cause of liver-related mortality and, so far, no effective antifibrotic drug is available. Galunisertib, a TGF-β receptor type I kinase inhibitor, is a potential candidate for the treatment of liver fibrosis. Here, we evaluated the potency of galunisertib in a human ex vivo model of liver fibrosis.Experimental Approach: Antifibrotic potency and associated mechanisms were studied ex vivo, using both healthy and cirrhotic human precision-cut liver slices. Fibrosis-related parameters, both transcriptional and translational level, were assessed after treatment with galunisertib.Key Results: Galunisertib showed a prominent antifibrotic potency. Phosphorylation of SMAD2 was inhibited, while that of SMAD1 remained unchanged. In healthy and cirrhotic human livers, spontaneous transcription of numerous genes encoding collagens, including collagen type I, α 1, collagen maturation, non-collageneous extracellular matrix (ECM) components, ECM remodelling and selected ECM receptors was significantly decreased. The reduction of fibrosis-related transcription was paralleled by a significant inhibition of procollagen I C-peptide released by both healthy and cirrhotic human liver slices. Moreover, galunisertib showed similar antifibrotic potency in human and rat lives.Conclusions and Implications: Galunisertib is a drug that deserves to be further investigated for the treatment of liver fibrosis. Inhibition of SMAD2 phosphorylation is probably a central mechanism of action. In addition, blocking the production and maturation of collagens and promoting their degradation are related to the antifibrotic action of galunisertib. [ABSTRACT FROM AUTHOR]

Background: In patients with resectable synchronous colorectal liver metastases (CRLM), either two-staged or simultaneous resections of the primary tumor and liver metastases are performed. Data on radiofrequency ablation (RFA) for the treatment of CRLM during a simultaneous procedure is lacking. The primary aim was to analyze short-term and long-term outcome of RFA in simultaneous treatment. A secondary aim was to compare simultaneous resection with the colorectal-first approach. Methods: Retrospective analysis of 241 patients with colorectal cancer and synchronous CRLM between 2000–2016. Median follow-up was 36.1 months (IQR 18.2–58.8 months). A multivariable analysis was performed to analyze the postoperative morbidity, using the comprehensive complication index. A propensity matched analysis was performed to compare survival rates. Results: In multivariable analysis, the best predictor of lower complication severity was treatment with RFA (p = 0.040). Higher complication rates were encountered in patients who underwent an abdominoperineal resection (p = 0.027) or age > 60 years (p = 0.022). The matched analysis showed comparable overall survival in RFA treated patients versus patients undergoing a liver resection with a five year overall survival of 39.4% and 37.5%, respectively (p = 0.782). In a second matched analysis, 5-year overall survival rates in simultaneously treated patients (43.8%) was comparable to patients undergoing the colorectal first approach (43.0%, p = 0.223). Conclusions: RFA treatment of CRLM in simultaneous procedures is associated with a lower complication severity and non-inferior oncological outcome as compared to partial liver resection. RFA should be considered a useful alternative to liver resection. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) is a classical example of inflammation-linked cancer and is characterized by hypervascularity suggesting rich angiogenesis. Cycloxygenase-2 (COX-2) is a potent mediator of inflammation and is considered to upregulate angiogenesis. The aims of the study are (1) to analyze expression of Cox-2 mRNA, Cox-2 protein, miR-16, miR-21 and miR-101 in HCC and adjacent liver parenchyma in cirrhotic and noncirrhotic liver, (2) to investigate the relation between COX-2 expression, miR-21 expression and angiogenic factors in these tissues and (3) to investigate the association between miR-16 and miR-101 and COX-2 expression. Methods: Tissue samples of HCC and adjacent liver parenchyma of 21 noncirrhotic livers and 20 cirrhotic livers were analyzed for COX-2 expression at the mRNA level (qRT-PCR) and at the protein level by Western blot and immunohistochemistry. Gene expression of VEGFA, VEGFR1, VEGFR2, Ang-1, Ang-2 and Tie-2 were correlated with COX-2 levels. miR-16, miR-21 and miR-101 gene expression levels were quantified in HCC tumor tissue. Results: COX-2 mRNA and protein levels were lower in HCC as compared to adjacent liver parenchyma both in cirrhotic and noncirrhotic liver. COX-2 protein localized mainly in vascular and sinusoidal endothelial cells and in Kupffer cells. At the mRNA level but not at the protein level, COX-2 correlated with mRNA levels of angiogenic factors VEGFR1, Ang-1, and Tie2. miR-21 expression was higher in cirrhotic tissues versus noncirrhotic tissues. MiR-101 expression was lower in cirrhotic versus noncirrhotic adjacent liver parenchyma. None of the miRNAs correlelated with COX-2 expression. miR-21 correlated negatively with Tie-2 receptor in adjacent liver parenchyma. Conclusions: In human HCC, COX-2 mRNA but not COX-2 protein levels are associated with expression levels of angiogenic factors. MiR-21 levels are not associated with angiogenic molecules. MiR-16 and miR-101 levels do not correlate with COX-2 mRNA and protein levels. [ABSTRACT FROM AUTHOR]

Unlabelled: The prerequisite for liver transplantation as a therapeutic option for inherited metabolic diseases should be that the enzyme defect, being responsible for the major clinical (hepatic and/or extra-hepatic) abnormalities, is localised in the liver. Furthermore, no adequate dietary or pharmacological treatment should be available or such treatment should have an unacceptable influence on the quality of life. We report an infant, who developed end-stage liver disease with persistent lactic acidaemia in his first months of life. Analysis of the mitochondrial respiratory chain in liver tissue revealed a combined partial complex I and IV deficiency. No extra-hepatic involvement could be demonstrated by careful screening for multiple organ involvement, including analysis of the mitochondrial respiratory chain in muscle tissue and cultured skin fibroblasts. The boy received a reduced size liver graft at the age of 8 months. He recovered successfully. Almost 5 years after transplantation he is in good clinical condition. No clinical or biochemical signs of any organ dysfunction have been demonstrated. The considerations on which basis it was decided that there was no contra-indication to perform liver transplantation in this patient are discussed.Conclusion: The possibility of a mitochondrial respiratory chain deficiency should be considered in liver disease of unknown origin prior to liver transplantation. Liver transplantation is a therapeutic option in mitochondrial respiratory chain deficiency-based end-stage liver disease provided that extra-hepatic involvement is carefully excluded. [ABSTRACT FROM AUTHOR]

Liver fibrosis is the progressive accumulation of connective tissue ultimately resulting in loss of organ function. Currently, no effective antifibrotics are available due to a lack of reliable human models. Here we investigated the fibrotic process in human precision-cut liver slices (PCLS) and studied the efficacy of multiple putative antifibrotic compounds. Our results demonstrated that human PCLS remained viable for 48 h and the early onset of fibrosis was observed during culture, as demonstrated by an increased gene expression of Heat Shock Protein 47 (HSP47) and Pro-Collagen 1A1 (PCOL1A1) as well as increased collagen 1 protein levels. SB203580, a specific inhibitor of p38 mitogen-activated protein kinase (MAPK) showed a marked decrease in HSP47 and PCOL1A1 gene expression, whereas specific inhibitors of Smad 3 and Rac-1 showed no or only minor effects. Regarding the studied antifibrotics, gene levels of HSP47 and PCOL1A1 could be down-regulated with sunitinib and valproic acid, while PCOL1A1 expression was reduced following treatment with rosmarinic acid, tetrandrine and pirfenidone. These results are in contrast with prior data obtained in rat PCLS, indicating that antifibrotic drug efficacy is clearly species-specific. Thus, human PCLS is a promising model for liver fibrosis. Moreover, MAPK signaling plays an important role in the onset of fibrosis in this model and transforming growth factor beta pathway inhibitors appear to be more effective than platelet-derived growth factor pathway inhibitors in halting fibrogenesis in PCLS. [ABSTRACT FROM AUTHOR]