18 research outputs found

    Epigenetic modulation of radiation-induced diacylglycerol kinase alpha expression prevents pro-fibrotic fibroblast response

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    Radiotherapy, a common component in cancer treatment, can induce adverse effects including fibrosis in co-irradiated tissues. We previously showed that differential DNA methylation at an enhancer of diacylglycerol kinase alpha (DGKA) in normal dermal fibroblasts is associated with radiation-induced fibrosis. After irradiation, the transcription factor EGR1 is induced and binds to the hypomethylated enhancer, leading to increased DGKA and pro-fibrotic marker expression. We now modulated this DGKA induction by targeted epigenomic and genomic editing of the DGKA enhancer and administering epigenetic drugs. Targeted DNA demethylation of the DGKA enhancer in HEK293T cells resulted in enrichment of enhancer-related histone activation marks and radiation-induced DGKA expression. Mutations of the EGR1-binding motifs decreased radiation-induced DGKA expression in BJ fibroblasts and caused dysregulation of multiple fibrosis-related pathways. EZH2 inhibitors (GSK126, EPZ6438) did not change radiation-induced DGKA increase. Bromodomain inhibitors (CBP30, JQ1) suppressed radiation-induced DGKA and pro-fibrotic marker expression. Similar drug effects were observed in donor-derived fibroblasts with low DNA methylation. Overall, epigenomic manipulation of DGKA expression may offer novel options for a personalized treatment to prevent or attenuate radiotherapy-induced fibrosis

    Quality of health care and the need for assessment

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    Objective: In many hospitals of developing countries quality of care is below the expected standard to maintain patient safety. In 2006, health care experts from Tanzania and Germany collaborated on a set of indicators to be used as a hospital performance assessment tool. The aim of this study was to introduce this tool and check its feasibility for use in a Tanzanian regional hospital.Methods: Within the hospital, independent observers assessed quantitatively structural quality and the performance of health care encounter using an itemized scale from 0 (0%) to 2 (100%) for each defined item. Outcome parameters were taken from the annual hospital report. In addition, semi-qualitative interviews with staff and patients were held to a) assess staff knowledge of the treatment guidelines published by the Tanzanian Ministry of Health and Social Welfare (MoHSW), b) assess attitudes and user motivation and c) authenticate the quantitative findings in a mixed-method triangulation approach.Results: Structural quality in maternity was at 75% of the expected standard, while process quality ranged from 36% (Care of the newborn with APGAR score < 4) to 47% (normal delivery procedure). Staff knowledge ranged between 64% and 87% with low motivation and commitment given as contributing factors. Outcome (maternal mortality) was 481/100,000 live births with an infant mortality rate of 10%. Discussion: The tool appeared to be feasible and effective in judging care quality. It provides a model for continuous quality improvement. Motivation of health care workers, a strong determinant of care process quality, might be improved by strengthening internal factors in health facilities. For conclusive validation, further studies using the tool must be conducted with larger numbers of institutions.Keywords: Quality of health care, Quality assessment, Quality assurance, Continuous Quality Improvemen

    Prognostic Value of Bioactive Adrenomedullin in Critically Ill Patients with COVID-19 in Germany: An Observational Cohort Study

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    The coronavirus disease 2019 (COVID-19) pandemic has placed a significant burden on hospitals worldwide. Objective biomarkers for early risk stratification and clinical management are still lacking. The aim of this work was to determine whether bioactive adrenomedullin can assist in the risk stratification and clinical management of critically ill COVID-19 patients. Fifty-three patients with confirmed COVID-19 were included in this prospective observational cohort study between March and April 2020. Bioactive adrenomedullin (bio-ADM) plasma concentration was measured daily for seven days after admission. The prognostic value and clinical significance of bio-ADM plasma levels were evaluated for the severity of respiratory failure, the need for extracorporeal organ support and outcome (28-day mortality). Bio-ADM levels increased with the severity of acute respiratory distress syndrome (ARDS; p < 0.001) and were significantly elevated in invasively ventilated patients (p = 0.006) and patients in need of extracorporeal membrane oxygenation (p = 0.040) or renal replacement therapy (RRT; p < 0.001) compared to patients without these conditions. Non-survivors showed significantly higher bio-ADM levels than survivors (p = 0.010). Bio-ADM levels predicted 28-day mortality (C-index 0.72, 95% confidence interval 0.56–0.87, p < 0.001). Bio-ADM plasma levels correlate with disease severity, the need for extracorporeal organ assistance, and outcome, and highlight the promising value of bio-ADM in the early risk stratification and management of patients with COVID-19

    TAL1 activation in T-cell acute lymphoblastic leukemia: a novel oncogenic 3’ neo-enhancer

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    T-cell acute lymphocytic leukemia protein 1 (TAL1) is one of the most frequently deregulated oncogenes in T-cell acute lymphoblastic leukemia (T-ALL). Its deregulation can occur through diverse cis-alterations, including SIL-TAL1 microdeletions, translocations with T-cell Receptor loci, and more recently described upstream intergenic non-coding mutations. These mutations consist of recurrent focal microinsertions that create an oncogenic neo-enhancer accompanied by activating epigenetic marks. This observation laid the groundwork for an innovative paradigm concerning the activation of proto-oncogenes via genomic alterations of non-coding intergenic regions. However, for the majority of TALL expressing TAL1 (TAL1 +), the deregulation mechanism remains 'unresolved'. We took advantage of H3K27ac and H3K4me3 chromatin immunoprecipitation sequencing data of eight cases of TALL , including five TAL1 + cases. We identified a putative novel oncogenic neo-enhancer downstream of TAL1 in an unresolved monoallelic TAL1 + case. A rare but recurrent somatic heterozygous microinsertion within this region creates a de novo binding site for MYB transcription factor. Here we demonstrate that this mutation leads to increased enhancer activity, gain of active epigenetic marks, and TAL1 activation via recruitment of MYB. These results highlight the diversity of non-coding mutations that can drive oncogene activation

    Histone H3K27 demethylase KDM6A is an epigenetic gatekeeper of mTORC1 signalling in cancer

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    ObjectiveLarge-scale genome sequencing efforts of human tumours identified epigenetic modifiers as one of the most frequently mutated gene class in human cancer. However, how these mutations drive tumour development and tumour progression are largely unknown. Here, we investigated the function of the histone demethylase KDM6A in gastrointestinal cancers, such as liver cancer and pancreatic cancer.DesignGenetic alterations as well as expression analyses of KDM6A were performed in patients with liver cancer. Genetic mouse models of liver and pancreatic cancer coupled with Kdm6a-deficiency were investigated, transcriptomic and epigenetic profiling was performed, and in vivo and in vitro drug treatments were conducted.ResultsKDM6A expression was lost in 30% of patients with liver cancer. Kdm6a deletion significantly accelerated tumour development in murine liver and pancreatic cancer models. Kdm6a-deficient tumours showed hyperactivation of mTORC1 signalling, whereas endogenous Kdm6a re-expression by inducible RNA-interference in established Kdm6a-deficient tumours diminished mTORC1 activity resulting in attenuated tumour progression. Genome-wide transcriptional and epigenetic profiling revealed direct binding of Kdm6a to crucial negative regulators of mTORC1, such as Deptor, and subsequent transcriptional activation by epigenetic remodelling. Moreover, in vitro and in vivo genetic epistasis experiments illustrated a crucial function of Deptor and mTORC1 in Kdm6a-dependent tumour suppression. Importantly, KDM6A expression in human tumours correlates with mTORC1 activity and KDM6A-deficient tumours exhibit increased sensitivity to mTORC1 inhibition.ConclusionKDM6A is an important tumour suppressor in gastrointestinal cancers and acts as an epigenetic toggle for mTORC1 signalling. Patients with KDM6A-deficient tumours could benefit of targeted therapy focusing on mTORC1 inhibition

    The age of the bone marrow microenvironment influences B-cell acute lymphoblastic leukemia progression via CXCR5-CXCL13

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    B-cell acute lymphoblastic leukemia (B-ALL) occurs most commonly in children, while chronic myeloid leukemia (CML) is more frequent in adults. The myeloid bias of hematopoiesis in elderly individuals has been considered causative, butthe age of the bone marrow(BM) microenvironment (BMM) may be contributory. Using various murine models of B-ALL in young versus old mice, we recapitulated B-ALL preponderance in children versus adults. We showeddifferential effectsof young versus oldBM macrophageson B-ALL cell function.Molecular profiling using RNA- and ATAC-seq revealed pronounced differences in young versus old BMM-derived macrophages and enrichment for gene sets associated with inflammation. In concordance with the role of C-X-C motif chemokine (CXCL) 13 for disease-associated B cell chemoattraction, we found CXCL13 to be highly expressed in young macrophages on a translational compared to a transcriptional level. Inhibition of CXCL13 in BM macrophages impaired leukemia cell migration and decreased the proliferation of cocultured B-ALL cells, while recombinant CXCL13 increasedpAKT and B-ALL cell expansion.Pretreatment of B-ALL-initiating cells with CXCL13 accelerated B-ALL progression. Deficiency of Cxcr5, the receptor for CXCL13, on B-ALL-initiating cells prolonged murine survival, while high expression of CXCR5 in pediatric B-ALL may predict central nervous system relapse. CXCL13 staining was increased in bone sections from pediatric compared to adult B-ALL patients. Taken together, our study shows that the age of the BMM and, in particular, BM macrophages influence the leukemia phenotype. The CXCR5-CXCL13-axis may act as prognostic marker andan attractive novel target for the treatment of B-ALL
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