Search

2016 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved. Instituciones participantes: 1Department of Internal Medicine III, University Hospital, RWTH Aachen, Aachen, Germany; 2Merck Serono Geneva Research Centre, Case postale 54, chemin des Mines 9, Geneva CH-1211 20, Switzerland; 3Dutch Molecular Pathology Center, Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3508 TB Utrecht, The Netherlands; 4University Medical Center Groningen, Department of Pediatrics, University of Groningen, NL-9713 Groningen, The Netherlands, Background & Aims: During liver inflammation, triggering fibrogenesis and carcinogenesis immune cells play a pivotal role. In the present study we investigated the role of CCL5 in human and in murine models of chronic liver inflammation leading to hepatocellular carcinoma (HCC) development. Methods: CCL5 expression and its receptors were studied in well-defined patients with chronic liver disease (CLD) and in two murine inflammation based HCC models. The role of CCL5 in inflammation, fibrosis, tumor initiation and progression was analyzed in different cell populations of NEMODhepa/CCL5-/- animals and after bone marrow transplantation (BMT). For therapeutic intervention Evasin-4 was injected for 24 h or 8 weeks. Results: In CLD patients, CCL5 and its receptor CCR5 are overexpressed – an observation confirmed in the Mdr2-/- and NEMODhepa model. CCL5 deletion in NEMODhepa mice diminished hepatocyte apoptosis, compensatory proliferation and fibrogenesis due to reduced immune cell infiltration. Especially, CD45+/Ly6G+granulocytes, CD45+/CD11b+/Gr1.1+/F4/80+ proinflammatory monocytes, CD4+ and CD8+ T cells were decreased. One year old NEMODhepa/CCL5-/- mice displayed smaller and less malignant tumors, characterized by reduced proliferative capacity and less pronounced angiogenesis. We identified hematopoietic cells as the main source of CCL5, while CCL5 deficiency did not sensitise NEMODhepa hepatocytes towards TNFa induced apoptosis. Finally, therapeutic intervention with Evasin-4 over a period of 8 weeks ameliorated liver disease progression. Conclusion: We identified an important role of CCL5 in human and functionally in mice with disease progression, especially HCC development. A novel approach to inhibit CCL5 in vivo thus appears encouraging for patients with CLD. Lay summary: Our present study identifies the essential role of the chemoattractive cytokine CCL5 for liver disease progression and especially hepatocellular carcinoma development in men and mice. Finally, IZKF (UKA, RWTH Aachen), Depto. de Inmunología, Oftalmología y ORL, Fac. de Medicina, TRUE, pub

Polyploid cells, which contain more than one set of chromosome pairs, are very common in nature. Polyploidy can provide cells with several potential benefits over their diploid counterparts, including an increase in cell size, contributing to organ growth and tissue homeostasis, and improving cellular robustness via increased tolerance to genomic stress and apoptotic signals. Here, we focus on why polyploidy in the cell occurs and which stress responses and molecular signals trigger cells to become polyploid. Moreover, we discuss its crucial roles in cell growth and tissue regeneration in the heart, liver, and other tissues.

Neuroblastoma affects mostly young children, bearing a high morbidity and mortality. Liquid biopsies, e.g., molecular analysis of circulating tumor-derived nucleic acids in blood, offer a minimally invasive diagnostic modality. Cell-free RNA (cfRNA) is released by all cells, especially cancer. It circulates in blood packed in extracellular vesicles (EV) or attached to proteins. We studied the feasibility of analyzing cfRNA and EV, isolated by size exclusion chromatography (SEC), from platelet-poor plasma from healthy controls ( n = 40) and neuroblastoma patients with localized ( n = 10) and metastatic disease ( n = 30). The mRNA content was determined using several multiplex droplet digital PCR (ddPCR) assays for a neuroblastoma-specific gene panel ( PHOX2B, TH, CHRNA3) and a cell cycle regulation panel ( E2F1, CDC6, ATAD2, H2AFZ, MCM2, DHFR). We applied corrections for the presence of platelets. We demonstrated that neuroblastoma-specific markers were present in plasma from 14/30 patients with metastatic disease and not in healthy controls and patients with localized disease. Most cell cycle markers had a higher expression in patients. The mRNA markers were mostly present in the EV-enriched SEC fractions. In conclusion, cfRNA can be isolated from plasma and EV and analyzed using multiplex ddPCR. cfRNA is an interesting novel liquid biopsy-based target to explore further.

Abstract: Hyperglycaemia in pregnancy (HIP) is a pregnancy complication characterized by mild to moderate hyperglycaemia that negatively impacts short- and long-term health of mother and child. However, relationships between severity and timing of pregnancy hyperglycaemia and postpartum outcomes have not been systemically investigated. We investigated the impact of hyperglycaemia developing during pregnancy (gestational diabetes mellitus, GDM) or already present pre-mating (pre-gestational diabetes mellitus, PDM) on maternal health and pregnancy outcomes. GDM and PDM were induced in C57BL/6NTac mice by combined 60% high fat diet (HF) and low dose streptozotocin (STZ). Animals were screened for PDM prior to mating, and all underwent an oral glucose tolerance test on gestational day (GD)15. Tissues were collected at GD18 or at postnatal day (PN)15. Among HFSTZ-treated dams, 34% developed PDM and 66% developed GDM, characterized by impaired glucose-induced insulin release and inadequate suppression of endogenous glucose production. No increased adiposity or overt insulin resistance was observed. Furthermore, markers of non-alcoholic fatty liver disease (NAFLD) were significantly increased in PDM at GD18 and were positively correlated with basal glucose levels at GD18 in GDM dams. By PN15, NAFLD markers were also increased in GDM dams. Only PDM affected pregnancy outcomes such as litter size. Our findings indicate that GDM and PDM, resulting in disturbances of maternal glucose homeostasis, increase the risk of postpartum NAFLD development, related to the onset and severity of pregnancy hyperglycaemia. These findings signal a need for earlier monitoring of maternal glycaemia and more rigorous follow-up of maternal health after GDM and PDM pregnancy in humans. (Figure presented.). Key points: We studied the impact of high-fat diet/streptozotocin induced hyperglycaemia in pregnancy in mice and found that this impaired glucose tolerance and insulin release. Litter size a

BACKGROUND: Glycogen storage disease type 1a (GSD Ia) is an inborn error of metabolism caused by a defect in glucose-6-phosphatase (G6PC1) activity, which induces severe hepatomegaly and increases the risk for liver cancer. Hepatic GSD Ia is characterized by constitutive activation of Carbohydrate Response Element Binding Protein (ChREBP), a glucose-sensitive transcription factor. Previously, we showed that ChREBP activation limits non-alcoholic fatty liver disease (NAFLD) in hepatic GSD Ia. As ChREBP has been proposed as a pro-oncogenic molecular switch that supports tumour progression, we hypothesized that ChREBP normalization protects against liver disease progression in hepatic GSD Ia.METHODS: Hepatocyte-specific G6pc knockout (L-G6pc -/-) mice were treated with AAV-shChREBP to normalize hepatic ChREBP activity. RESULTS: Hepatic ChREBP normalization in GSD Ia mice induced dysplastic liver growth, massively increased hepatocyte size, and was associated with increased hepatic inflammation. Furthermore, nuclear levels of the oncoprotein Yes Associated Protein (YAP) were increased and its transcriptional targets were induced in ChREBP-normalized GSD Ia mice. Hepatic ChREBP normalization furthermore induced DNA damage and mitotic activity in GSD Ia mice, while gene signatures of chromosomal instability, the cytosolic DNA-sensing cGAS-STING pathway, senescence, and hepatocyte dedifferentiation emerged.CONCLUSIONS: In conclusion, our findings indicate that ChREBP activity limits hepatomegaly while decelerating liver disease progression and protecting against chromosomal instability in hepatic GSD Ia. These results disqualify ChREBP as a therapeutic target for treatment of liver disease in GSD Ia. In addition, they underline the importance of establishing the context-specific roles of hepatic ChREBP to define its therapeutic potential to prevent or treat advanced liver disease.