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1.
Front Immunol ; 15: 1334616, 2024.
Article in English | MEDLINE | ID: mdl-38571946

ABSTRACT

Staphylococcus aureus is a highly successful pathogen infecting various body parts and forming biofilms on natural and artificial surfaces resulting in difficult-to-treat and chronic infections. We investigated the secreted cytokines and proteomes of isolated peripheral blood mononuclear cells (PBMCs) from healthy volunteers exposed to methicillin-resistant S. aureus (MRSA) biofilms or planktonic bacteria. Additionally, the cytokine profiles in sera from patients with community-acquired pneumonia (CAP) caused by S. aureus were investigated. The aim was to gain insights into the immune response involved and differentiate between the planktonic and sessile MRSA forms. We identified 321 and 298 targets that were significantly differently expressed in PBMCs when exposed to planktonic or biofilm-embedded bacteria, respectively. PBMCs exposed to planktonic MRSA cells secreted increased levels of TNF-α, while IL-18 was elevated when exposed to the biofilm. The machine-learning analyses of the cytokine profiles obtained for the in vitro PBMCs and CAP sera distinguished between the two types of bacteria forms based on cytokines IL-18, IL12, and IL-17, and with a lower importance IL-6. Particularly, IL-18 which has not been correlated with S. aureus biofilms so far might represent a suitable marker for monitoring chronification during MRSA infection to individualize the therapy, but this hypothesis must be proved in clinical trials.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Humans , Methicillin-Resistant Staphylococcus aureus/physiology , Cytokines , Staphylococcus aureus , Interleukin-18 , Proteome , Plankton , Leukocytes, Mononuclear , Biofilms
2.
Infection ; 51(6): 1669-1678, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37166617

ABSTRACT

PURPOSE: Identification of patients at risk of complicated or more severe COVID-19 is of pivotal importance, since these patients might require monitoring, antiviral treatment, and hospitalization. In this study, we prospectively evaluated the SACOV-19 score for its ability to predict complicated or more severe COVID-19. METHODS: In this prospective multicenter study, we included 124 adult patients with acute COVID-19 in three German hospitals, who were diagnosed in an early, uncomplicated stage of COVID-19 within 72 h of inclusion. We determined the SACOV-19 score at baseline and performed a follow-up at 30 days. RESULTS: The SACOV-19 score's AUC was 0.816. At a cutoff of > 3, it predicted deterioration to complicated or more severe COVID-19 with a sensitivity of 94% and a specificity of 55%. It performed significantly better in predicting complicated COVID-19 than the random tree-based SACOV-19 predictive model, the CURB-65, 4C mortality, or qCSI scores. CONCLUSION: The SACOV-19 score is a feasible tool to aid decision making in acute COVID-19.


Subject(s)
COVID-19 , Adult , Humans , COVID-19/diagnosis , Prospective Studies , SARS-CoV-2 , Hospitalization , Hospitals
3.
Ann Clin Transl Neurol ; 10(2): 204-212, 2023 02.
Article in English | MEDLINE | ID: mdl-36479924

ABSTRACT

OBJECTIVE: Serum neurofilament light chain (sNfL) is a biomarker for neuroaxonal damage and has been found to be elevated in several neurological diseases with neuronal destruction. New onset of confusion is a hallmark of severity in infections. The objective of this study was to determine whether sNfL levels are increased in patients with community-acquired pneumonia (CAP) and if increased sNfL levels are associated with disease-associated confusion or disease severity. METHODS: In this observational study, sNfL levels were determined with single-molecule array technology in CAP patients of the CAPNETZ cohort with validated CRB (confusion, respiratory rate, and blood pressure)-65 score. We determined associations between log-transformed sNfL concentrations, well-defined clinical characteristics, and unfavorable outcome in multivariable analyses. Receiver operating characteristic (ROC) analysis was performed to assess the prediction accuracy of sNfL levels for confusion in CAP patients. RESULTS: sNfL concentrations were evaluated in 150 CAP patients. Patients with confusion had higher sNfL levels as compared to non-confusion patients of comparable overall disease severity. ROC analysis of sNfL and confusion provided an area under the curve (AUC) of 0.73 (95% CI 0.62-0.82). Log-transformed sNfL levels were not associated with general disease severity. In a logistic regression analysis, log2-sNfL was identified as a strong predictor for an unfavorable outcome. INTERPRETATION: sNfL levels are specifically associated with confusion and not with pneumonia disease severity, thus reflecting a potential objective marker for encephalopathy in these patients. Furthermore, sNfL levels are also associated with unfavorable outcome in these patients and might help clinicians to identify patients at risk.


Subject(s)
Brain Diseases , Pneumonia , Humans , Intermediate Filaments , Biomarkers , Pneumonia/diagnosis , ROC Curve
4.
Biochimie ; 193: 115-125, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34740743

ABSTRACT

The transcriptional regulatory network (TRN) in a cell orchestrates spatio-temporal expression of genes to generate cellular responses for maintenance, reproduction, development and survival of the cell and its hosting organism. Transcription factors (TF) regulate the expression of their target genes (TG) and are the fundamental units of TRN. Several databases have been developed to catalogue human TRN based on low- and high-throughput experimental and computational studies considering their importance in understanding cellular physiology. However, literature lacks their comparative assessment on the strengths and weaknesses. We compared over 2.2 million regulatory pairs between 1379 TF and 22,518 TG from 14 resources. Our study reveals that the TF and TG were common across data resources but not their regulatory pairs. TF and TG of the regulatory pairs showed weak expression correlation, significant gene ontology overlap, co-citations in PubMed and low numbers of TF-TG pairs representing transcriptional repression relationships. We assigned each TF-TG regulatory pair a combined confidence score reflecting its reliability based on its presence in multiple databases. The assembled TRN contains 2,246,598 TF-TG pairs, of which, 44,284 with information on TF's activating or repressing effects on their TG and is available upon request. This study brings the information about transcriptional regulation scattered over the literature and databases at one place in the form of one of the most comprehensive and complete human TRN assembled to date. It will be a valuable resource for benchmarking TRN prediction tools, and to the scientific community working in functional genomics, gene expression and regulation analysis.


Subject(s)
Databases, Nucleic Acid , Gene Expression Profiling , Gene Expression Regulation , Gene Regulatory Networks , Humans
5.
Infection ; 50(2): 359-370, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34279815

ABSTRACT

PURPOSE: While more advanced COVID-19 necessitates medical interventions and hospitalization, patients with mild COVID-19 do not require this. Identifying patients at risk of progressing to advanced COVID-19 might guide treatment decisions, particularly for better prioritizing patients in need for hospitalization. METHODS: We developed a machine learning-based predictor for deriving a clinical score identifying patients with asymptomatic/mild COVID-19 at risk of progressing to advanced COVID-19. Clinical data from SARS-CoV-2 positive patients from the multicenter Lean European Open Survey on SARS-CoV-2 Infected Patients (LEOSS) were used for discovery (2020-03-16 to 2020-07-14) and validation (data from 2020-07-15 to 2021-02-16). RESULTS: The LEOSS dataset contains 473 baseline patient parameters measured at the first patient contact. After training the predictor model on a training dataset comprising 1233 patients, 20 of the 473 parameters were selected for the predictor model. From the predictor model, we delineated a composite predictive score (SACOV-19, Score for the prediction of an Advanced stage of COVID-19) with eleven variables. In the validation cohort (n = 2264 patients), we observed good prediction performance with an area under the curve (AUC) of 0.73 ± 0.01. Besides temperature, age, body mass index and smoking habit, variables indicating pulmonary involvement (respiration rate, oxygen saturation, dyspnea), inflammation (CRP, LDH, lymphocyte counts), and acute kidney injury at diagnosis were identified. For better interpretability, the predictor was translated into a web interface. CONCLUSION: We present a machine learning-based predictor model and a clinical score for identifying patients at risk of developing advanced COVID-19.


Subject(s)
COVID-19 , Early Warning Score , Area Under Curve , COVID-19/diagnosis , Humans , Machine Learning , Retrospective Studies , SARS-CoV-2
7.
Front Immunol ; 12: 607217, 2021.
Article in English | MEDLINE | ID: mdl-33767693

ABSTRACT

Large clinical trials testing hydrocortisone therapy in septic shock have produced conflicting results. Subgroups may benefit of hydrocortisone treatment depending on their individual immune response. We performed an exploratory analysis of the database from the international randomized controlled clinical trial Corticosteroid Therapy of Septic Shock (CORTICUS) employing machine learning to a panel of 137 variables collected from the Berlin subcohort comprising 83 patients including demographic and clinical measures, organ failure scores, leukocyte counts and levels of circulating cytokines. The identified theranostic marker was validated against data from a cohort of the Hellenic Sepsis Study Group (HSSG) (n = 246), patients enrolled in the clinical trial of Sodium Selenite and Procalcitonin Guided Antimicrobial Therapy in Severe Sepsis (SISPCT, n = 118), and another, smaller clinical trial (Crossover study, n = 20). In addition, in vitro blood culture experiments and in vivo experiments in mouse models were performed to assess biological plausibility. A low serum IFNγ/IL10 ratio predicted increased survival in the hydrocortisone group whereas a high ratio predicted better survival in the placebo group. Using this marker for a decision rule, we applied it to three validation sets and observed the same trend. Experimental studies in vitro revealed that IFNγ/IL10 was negatively associated with the load of (heat inactivated) pathogens in spiked human blood and in septic mouse models. Accordingly, an in silico analysis of published IFNγ and IL10 values in bacteremic and non-bacteremic patients with the Systemic Inflammatory Response Syndrome supported this association between the ratio and pathogen burden. We propose IFNγ/IL10 as a molecular marker supporting the decision to administer hydrocortisone to patients in septic shock. Prospective clinical studies are necessary and standard operating procedures need to be implemented, particularly to define a generic threshold. If confirmed, IFNγ/IL10 may become a suitable theranostic marker for an urging clinical need.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Hydrocortisone/therapeutic use , Interferon-gamma/blood , Interleukin-10/blood , Shock, Septic/blood , Shock, Septic/drug therapy , Adult , Aged , Animals , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/adverse effects , Biomarkers , Clinical Decision-Making , Disease Management , Disease Models, Animal , Female , Hemodynamics , Humans , Hydrocortisone/administration & dosage , Hydrocortisone/adverse effects , Lactic Acid/blood , Male , Mice , Middle Aged , Norepinephrine , Odds Ratio , Prognosis , Propensity Score , Shock, Septic/diagnosis , Shock, Septic/mortality , Treatment Outcome
8.
Mol Ther ; 29(1): 338-346, 2021 01 06.
Article in English | MEDLINE | ID: mdl-32966769

ABSTRACT

Complement factor C5a was originally identified as a powerful promoter of inflammation through activation of the C5a receptor 1 (C5ar1). Recent evidence suggests involvement of C5a not only in pro- but also in anti-inflammatory signaling. The present study aims to unveil the role of C5ar1 as potential therapeutic target in a murine sepsis model. Our study discloses a significantly increased survival in models of mild to moderate but not severe sepsis of C5ar1-deficient mice. The decreased mortality of C5ar1-deficient mice is accompanied by improved pathogen clearance and largely preserved liver function. C5ar1-deficient mice exhibited a significantly increased production of the pro-inflammatory mediator interferon-γ (IFN-γ) and a decreased production of the anti-inflammatory cytokine interleukin-10 (IL-10). Together, these data uncover C5a signaling as a mediator of immunosuppressive processes during sepsis and describe the C5ar1 and related changes of the IFN-γ to IL-10 ratio as markers for the immunological (dys)function accompanying sepsis.


Subject(s)
Biomarkers , Disease Susceptibility/immunology , Immunomodulation , Receptor, Anaphylatoxin C5a/metabolism , Sepsis/metabolism , Animals , Cytokines/metabolism , Disease Models, Animal , Immunity, Innate , Immunomodulation/drug effects , Inflammation Mediators/metabolism , Mice , Mice, Knockout , Molecular Targeted Therapy , Phenotype , Receptor, Anaphylatoxin C5a/antagonists & inhibitors , Receptor, Anaphylatoxin C5a/genetics , Sepsis/diagnosis , Sepsis/drug therapy , Sepsis/etiology
9.
Cells ; 9(11)2020 11 09.
Article in English | MEDLINE | ID: mdl-33182501

ABSTRACT

Acute myeloid leukaemia (AML) is a haematopoietic malignancy caused by a combination of genetic and epigenetic lesions. Activation of the oncoprotein FLT3 ITD (Fms-like tyrosine kinase with internal tandem duplications) represents a key driver mutation in 25-30% of AML patients. FLT3 is a class III receptor tyrosine kinase, which plays a role in cell survival, proliferation, and differentiation of haematopoietic progenitors of lymphoid and myeloid lineages. Mutant FLT3 ITD results in an altered signalling quality, which causes cell transformation. Recent evidence indicates an effect of FLT3 ITD on bone homeostasis in addition to haematological aberrations. Using gene expression data repositories of FLT3 ITD-positive AML patients, we identified activated cytokine networks that affect the formation of the haematopoietic niche by controlling osteoclastogenesis and osteoblast functions. In addition, aberrant oncogenic FLT3 signalling of osteogenesis-specific cytokines affects survival of AML patients and may be used for prognosis. Thus, these data highlight the intimate crosstalk between leukaemic and osteogenic cells within the osteohaematopoietic niche.


Subject(s)
Bone and Bones/pathology , Cytokines/metabolism , Homeostasis , Leukemia, Myeloid, Acute/pathology , Oncogenes , fms-Like Tyrosine Kinase 3/genetics , Animals , Cell Line, Tumor , Gene Duplication , Gene Expression Profiling , Gene Expression Regulation, Leukemic , Hematopoietic Stem Cells/metabolism , Humans , Leukemia, Myeloid, Acute/genetics , Mice , Osteoblasts/metabolism , Osteoblasts/pathology , Osteoclasts/metabolism , Osteoclasts/pathology , Osteogenesis , Prognosis , RAW 264.7 Cells , Signal Transduction , fms-Like Tyrosine Kinase 3/metabolism
10.
Environ Microbiol ; 22(9): 3722-3740, 2020 09.
Article in English | MEDLINE | ID: mdl-32583550

ABSTRACT

Mucormycosis is an emergent, fatal fungal infection of humans and warm-blooded animals caused by species of the order Mucorales. Immune cells of the innate immune system serve as the first line of defence against inhaled spores. Alveolar macrophages were challenged with the mucoralean fungus Lichtheimia corymbifera and subjected to biotinylation and streptavidin enrichment procedures followed by LC-MS/MS analyses. A total of 28 host proteins enriched for binding to macrophage-L. corymbifera interaction. Among those, the HSP70-family protein Hspa8 was found to be predominantly responsive to living and heat-killed spores of a virulent and an attenuated strain of L. corymbifera. Confocal scanning laser microscopy of infected macrophages revealed colocalization of Hspa8 with phagocytosed spores of L. corymbifera. The amount of detectable Hspa8 was dependent on the multiplicity of infection. Incubation of alveolar macrophages with an anti-Hspa8 antibody prior to infection reduced their capability to phagocytose spores of L. corymbifera. In contrast, anti-Hspa8 antibodies did not abrogate the phagocytosis of Aspergillus fumigatus conidia by macrophages. These results suggest an important contribution of the heat-shock family protein Hspa8 in the recognition of spores of the mucoralean fungus L. corymbifera by host alveolar macrophages and define a potential immunomodulatory therapeutic target.


Subject(s)
Heat-Shock Proteins/metabolism , Macrophages, Alveolar/physiology , Mucorales/metabolism , Animals , Antibodies/pharmacology , Aspergillus fumigatus , Cell Line , Fungal Proteins/genetics , Fungal Proteins/metabolism , Heat-Shock Proteins/genetics , Heat-Shock Proteins/immunology , Macrophages, Alveolar/drug effects , Macrophages, Alveolar/microbiology , Mice , Phagocytosis/drug effects , Proteomics , Spores, Fungal
11.
PLoS Comput Biol ; 16(2): e1007657, 2020 02.
Article in English | MEDLINE | ID: mdl-32097424

ABSTRACT

Upon exposure to different stimuli, resting macrophages undergo classical or alternative polarization into distinct phenotypes that can cause fatal dysfunction in a large range of diseases, such as systemic infection leading to sepsis or the generation of an immunosuppressive tumor microenvironment. Investigating gene regulatory and metabolic networks, we observed two metabolic switches during polarization. Most prominently, anaerobic glycolysis was utilized by M1-polarized macrophages, while the biosynthesis of inosine monophosphate was upregulated in M2-polarized macrophages. Moreover, we observed a switch in the urea cycle. Gene regulatory network models revealed E2F1, MYC, PPARγ and STAT6 to be the major players in the distinct signatures of these polarization events. Employing functional assays targeting these regulators, we observed the repolarization of M2-like cells into M1-like cells, as evidenced by their specific gene expression signatures and cytokine secretion profiles. The predicted regulators are essential to maintaining the M2-like phenotype and function and thus represent potential targets for the therapeutic reprogramming of immunosuppressive M2-like macrophages.


Subject(s)
Gene Regulatory Networks , Macrophage Activation , Macrophages/metabolism , Tumor Microenvironment , Anaerobiosis , Animals , Cytokines/metabolism , Gene Expression Profiling , Gene Expression Regulation , Glycolysis , Immunosuppression Therapy , Immunosuppressive Agents/therapeutic use , Inosine Monophosphate/metabolism , Mice , Mice, Inbred C57BL , Phenotype
12.
Mol Oncol ; 14(1): 129-138, 2020 01.
Article in English | MEDLINE | ID: mdl-31736271

ABSTRACT

The chromatin-organizing factor CCCTC-binding factor (CTCF) is involved in transcriptional regulation, DNA-loop formation, and telomere maintenance. To evaluate the clinical impact of CTCF in prostate cancer, we analyzed CTCF expression by immunohistochemistry on a tissue microarray containing 17 747 prostate cancers. Normal prostate tissue showed negative to low CTCF expression, while in prostate cancers, CTCF expression was seen in 7726 of our 12 555 (61.5%) tumors and was considered low in 44.6% and high in 17% of cancers. Particularly, high CTCF expression was significantly associated with the presence of the transmembrane protease, serine 2:ETS-related gene fusion: Only 10% of ERG-negative cancers, but 30% of ERG-positive cancers had high-level CTCF expression (P < 0.0001). CTCF expression was significantly associated with advanced pathological tumor stage, high Gleason grade (P < 0.0001 each), nodal metastasis (P = 0.0122), and early biochemical recurrence (P < 0.0001). Multivariable modeling revealed that the prognostic impact of CTCF was independent from established presurgical parameters such as clinical stage and Gleason grade of the biopsy. Comparison with key molecular alterations showed strong associations with the expression of the Ki-67 proliferation marker and presence of phosphatase and tensin homolog deletions (P < 0.0001 each). The results of our study identify CTCF expression as a candidate biomarker for prognosis assessment in prostate cancer.


Subject(s)
CCCTC-Binding Factor/metabolism , Gene Expression Regulation, Neoplastic/genetics , Oncogene Proteins, Fusion/genetics , Prostatic Neoplasms/metabolism , Serine Endopeptidases/genetics , Aged , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , CCCTC-Binding Factor/genetics , Cell Proliferation/genetics , Humans , Immunohistochemistry , Ki-67 Antigen/metabolism , Male , Middle Aged , Neoplasm Grading , Prognosis , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Sequence Deletion , Serine Endopeptidases/metabolism , Tissue Array Analysis , Transcriptional Regulator ERG/genetics , Transcriptional Regulator ERG/metabolism
13.
Eur Respir J ; 54(6)2019 12.
Article in English | MEDLINE | ID: mdl-31537702

ABSTRACT

BACKGROUND: The role of macrolide/ß-lactam combination therapy in community-acquired pneumonia (CAP) of moderate severity is a matter of debate. Macrolides expand the coverage to atypical pathogens and attenuate pulmonary inflammation, but have been associated with cardiovascular toxicity and drug interactions. We developed a decision tree based on aetiological and clinical parameters, which are available ex ante to support a personalised decision for or against macrolides for the best clinical outcome of the individual patient. METHODS: We employed machine learning in a cross-validation scheme based on a well-balanced selection of 4898 patients after propensity score matching to data available on admission of 6440 hospitalised patients with moderate severity (non-intensive care unit patients) from the observational, prospective, multinational CAPNETZ study. We aimed to improve the primary outcome of 180-day survival. RESULTS: We found a simple decision tree of patient characteristics comprising chronic cardiovascular and chronic respiratory comorbidities as well as leukocyte counts in the respiratory secretion at enrolment. Specifically, we found that patients without cardiovascular or patients with respiratory comorbidities and high leukocyte counts in the respiratory secretion benefit from macrolide treatment. Patients identified to be treated in compliance with our treatment suggestion had a lower mortality of 27% (OR 1.83, 95% CI 1.48-2.27; p<0.001) compared to the observed standard of care. CONCLUSION: Stratifying macrolide treatment in patients following a simple treatment rule may lead to considerably reduced mortality in CAP. A future randomised controlled trial confirming our result is necessary before implementing this rule into the clinical routine.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Machine Learning , Macrolides/therapeutic use , Pneumonia, Bacterial/drug therapy , beta-Lactams/therapeutic use , Adult , Aged , Aged, 80 and over , Community-Acquired Infections/drug therapy , Community-Acquired Infections/mortality , Drug Therapy, Combination , Europe , Female , Hospitalization , Humans , Male , Middle Aged , Pneumonia, Bacterial/mortality , Propensity Score , Prospective Studies , Severity of Illness Index , Treatment Outcome
14.
Nat Commun ; 10(1): 2459, 2019 May 31.
Article in English | MEDLINE | ID: mdl-31150008

ABSTRACT

The original version of this Article contained an error in the spelling of the author Jule Müller, which was incorrectly given as Julia Müller. Additionally, in Fig. 4a, the blue-red colour scale for fold change in ageing/disease regulation included a blue stripe in place of a red stripe at the right-hand end of the scale. These errors have been corrected in both the PDF and HTML versions of the Article.

15.
Mol Med ; 25(1): 19, 2019 05 16.
Article in English | MEDLINE | ID: mdl-31096912

ABSTRACT

BACKGROUND: The immune response of the critically ill after severe trauma is sex-specific and may explain the different progression of the disease. This may be explained by a different gene regulatory program of their peripheral immune cells. We investigated the progression of the transcription profiles of peripheral immune cells of the patients to elucidate their distinct physiological response and clinical course. METHODS: We compared transcription profiles of whole blood of male and female patients from a larger longitudinal study of critically ill patients after trauma. We developed a statistical analysis pipeline that synchronized the time lapse of the profiles based on the temporal severity score of each patient. RESULTS: This enabled to categorize the temporal progression of the disease into two pre-acute, an acute and two post-acute phases. Comparing gene regulation of male and female patients at each phase, we identified distinctively regulated molecular processes mainly in the immune response, but also in the regulation of metabolism allowing to cluster these discriminative gene sets into sets of highly related cellular processes. Compared to male patients and healthy controls, female patients showed upregulation of gene sets of innate immunity in the early phase, upregulation of wound healing processes during the acute phase and upregulation of adaptive immunity in the late phase indicating early recovery. In turn, during the pre-acute and acute phase, male patients showed less suppression of gene sets coding for enzymes of energy metabolism and anabolism, most prominently the tricarboxylic acid cycle and ß-oxidation, and cellular maintenance, such as cell cycle, DNA replication and damage response, and RNA metabolism. CONCLUSIONS: A stronger innate immune response at the very early phase of the disease may support early clearance of the pathogen and its associated molecular patterns. Upregulation of wound healing processes may explain reduced multiple organ failure during the acute phase. Down regulated energy metabolism during the acute phase may make female patients less susceptible to oxidative stress, the upregulated adaptive immune system reflects an earlier recovery and rebuilding of the adaptive immune system that may protect them from secondary infections. Follow up studies need to be performed confirming these observations experimentally.


Subject(s)
Leukocytes/metabolism , Adolescent , Adult , Critical Illness , Energy Metabolism/genetics , Energy Metabolism/physiology , Female , Gene Expression/genetics , Gene Expression/physiology , Gene Expression Regulation/genetics , Gene Expression Regulation/physiology , Humans , Longitudinal Studies , Male , Middle Aged , Multiple Organ Failure/genetics , Multiple Organ Failure/metabolism , Sex Factors , Wounds and Injuries/genetics , Wounds and Injuries/metabolism , Young Adult
16.
Mol Syst Biol ; 15(5): e8339, 2019 05 22.
Article in English | MEDLINE | ID: mdl-31118277

ABSTRACT

In chronic lymphocytic leukemia (CLL), a diverse set of genetic mutations is embedded in a deregulated epigenetic landscape that drives cancerogenesis. To elucidate the role of aberrant chromatin features, we mapped DNA methylation, seven histone modifications, nucleosome positions, chromatin accessibility, binding of EBF1 and CTCF, as well as the transcriptome of B cells from CLL patients and healthy donors. A globally increased histone deacetylase activity was detected and half of the genome comprised transcriptionally downregulated partially DNA methylated domains demarcated by CTCF CLL samples displayed a H3K4me3 redistribution and nucleosome gain at promoters as well as changes of enhancer activity and enhancer linkage to target genes. A DNA binding motif analysis identified transcription factors that gained or lost binding in CLL at sites with aberrant chromatin features. These findings were integrated into a gene regulatory enhancer containing network enriched for B-cell receptor signaling pathway components. Our study predicts novel molecular links to targets of CLL therapies and provides a valuable resource for further studies on the epigenetic contribution to the disease.


Subject(s)
Chromatin/chemistry , Gene Expression Regulation, Leukemic , Gene Regulatory Networks , Histones/chemistry , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Aged , Amino Acid Motifs , Binding Sites , CCCTC-Binding Factor/genetics , DNA/chemistry , DNA Methylation , Down-Regulation , Enhancer Elements, Genetic , Histone Deacetylases/genetics , Humans , Middle Aged , Promoter Regions, Genetic , Protein Binding , Trans-Activators/genetics
17.
Oncogene ; 38(24): 4773-4787, 2019 06.
Article in English | MEDLINE | ID: mdl-30820040

ABSTRACT

The receptor tyrosine kinase FLT3 is expressed in myeloid and lymphoid progenitor cells. Activating mutations in FLT3 occur in 25-30% of acute myeloid leukaemia (AML) patients. Most common are internal tandem duplications of sequence (ITD) leading to constitutive FLT3-ITD kinase activity with an altered signalling quality promoting leukaemic cell transformation. Here, we observed the attenuating role of the receptor-like protein tyrosine phosphatase (RPTP) CD45/Ptprc in FLT3 signalling in vivo. Low level expression of this abundant RPTP correlates with a poor prognosis of FLT3-ITD-positive AML patients. To get a further insight into the regulatory role of Ptprc in FLT3-ITD activity in vivo, Ptprc knock-out mice were bred with FLT3-ITD knock-in mice. Inactivation of the Ptprc gene in FLT3-ITD mice resulted in a drastically shortened life span and development of severe monocytosis, a block in B-cell development and anaemia. The myeloproliferative phenotype was associated with extramedullary haematopoiesis, splenohepatomegaly and severe alterations of organ structures. The phenotypic alterations were associated with increased transforming signalling of FLT3-ITD, including activation of its downstream target STAT5. These data reveal the capacity of Ptprc for the regulation of FLT3-ITD signalling activity in vivo. In addition, histopathology and computed tomography (CT) revealed an unexpected bone phenotype; the FLT3-ITD Ptprc-/- mice, but none of the controls, showed pronounced alterations in bone morphology and, in part, apparent features of osteoporosis. In the spleen, ectopic bone formation was observed. The observed bone phenotypes suggest a previously unappreciated capacity of FLT3-ITD (and presumably FLT3) to regulate bone development/remodelling, which is under negative control of CD45/Ptprc.


Subject(s)
Bone and Bones , Leukocyte Common Antigens/genetics , Myeloproliferative Disorders/genetics , Osteoporosis/genetics , fms-Like Tyrosine Kinase 3/genetics , Animals , Bone Development/genetics , Bone Remodeling/genetics , Cell Transformation, Neoplastic , Cells, Cultured , Choristoma/genetics , Choristoma/metabolism , Embryo, Mammalian , Female , Humans , Leukemia, Myeloid, Acute/complications , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/pathology , Leukocyte Common Antigens/deficiency , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Mutation , Myeloproliferative Disorders/complications , Myeloproliferative Disorders/pathology , Osteogenesis/genetics , Osteoporosis/metabolism , Osteoporosis/pathology , Phenotype , Porosity , Tandem Repeat Sequences/genetics
18.
Front Immunol ; 10: 219, 2019.
Article in English | MEDLINE | ID: mdl-30853959

ABSTRACT

The immunosuppressive tumor microenvironment (TME) established by tumor cells, stromal cells and inhibitory immune cells counteracts the function of tumor reactive T cells. Tumor associated macrophages (TAMs) showing functional plasticity contribute to this process as so called M2-like macrophages can suppress the function of effector T cells and promote their differentiation into regulatory T cells (Tregs). Furthermore, tumor antigen specific CD4+ T effector cells can essentially sustain anti-tumoral immune responses as shown for various tumor entities, thus suggesting that cognate interaction between tumor antigen-specific CD4+ Th1 cells and TAMs might shift the intra-tumoral M1/M2 ratio toward M1. This study demonstrates repolarization of M2-like PECs upon MHC II-restricted interaction with tumor specific CD4+ Th1 cells in vitro as shown by extensive gene and protein expression analyses. Moreover, adoptive transfer of OVA-specific OT-II cells into C57BL/6 mice bearing OVA expressing IAb-/- tumors resulted in increased accumulation of M1-like TAMs with enhanced M1 associated gene and protein expression profiles. Thus, this paper highlights a so far underestimated function of the CD4+ Th1/TAM axis in re-conditioning the immunosuppressive tumor microenvironment.


Subject(s)
Cell Communication , Macrophages/physiology , Neoplasms/immunology , Th1 Cells/physiology , Adoptive Transfer , Animals , Cell Polarity , Exudates and Transudates/cytology , Immune Tolerance , Mice , Mice, Inbred C57BL , Myeloid-Derived Suppressor Cells/physiology , Phenotype , Tumor Microenvironment/immunology
19.
Prostate ; 79(3): 302-311, 2019 02.
Article in English | MEDLINE | ID: mdl-30430607

ABSTRACT

BACKGROUND: The transcription factor CCAAT-enhancer-binding protein alpha (CEBPA) is a crucial regulator of cell proliferation and differentiation. Expression levels of CEBPA have been suggested to be prognostic in various tumor types. METHODS: Here, we analyzed the immunohistochemical expression of CEBPA in a tissue microarray containing more than 17 000 prostate cancer specimens with annotated clinical and molecular data including for example TMPRSS2:ERG fusion and PTEN deletion status. RESULTS: Normal prostate glands showed moderate to strong CEBPA staining, while CEBPA expression was frequently reduced (40%) or lost (30%) in prostate cancers. Absence of detectable CEBPA expression was markedly more frequent in ERG negative (45%) as compared to ERG positive cancers (20%, P < 0.0001). Reduced CEBPA expression was linked to unfavorable phenotype (P < 0.0001) and poor prognosis (P = 0.0008). Subgroup analyses revealed, that the prognostic value of CEBPA loss was entirely driven by tumors carrying both TMPRSS2:ERG fusions and PTEN deletions. In this subgroup, CEBPA loss was tightly linked to advanced tumor stage (P < 0.0001), high Gleason grade (P < 0.0001), positive nodal stage (0.0003), and early biochemical recurrence (P = 0.0007), while these associations were absent or markedly diminished in tumors with normal PTEN copy numbers and/or absence of ERG fusion. CONCLUSIONS: CEBPA is down regulated in about one third of prostate cancers, but the clinical impact of CEBPA loss is strictly limited to the subset of about 10% prostate cancers carrying both ERG fusion and deletions of the PTEN tumor suppressor. Our findings challenge the concept that prognostic molecular markers may be generally applicable to all prostate cancers.


Subject(s)
CCAAT-Enhancer-Binding Proteins/deficiency , Oncogene Proteins, Fusion/metabolism , PTEN Phosphohydrolase/deficiency , Prostatic Neoplasms/metabolism , Aged , CCAAT-Enhancer-Binding Proteins/biosynthesis , CCAAT-Enhancer-Binding Proteins/metabolism , Gene Dosage , Humans , Immunohistochemistry , Male , Middle Aged , Oncogene Proteins, Fusion/genetics , PTEN Phosphohydrolase/genetics , PTEN Phosphohydrolase/metabolism , Prognosis , Prostatectomy , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Prostatic Neoplasms/surgery , Tissue Array Analysis
20.
BMC Bioinformatics ; 20(1): 737, 2019 Dec 30.
Article in English | MEDLINE | ID: mdl-31888467

ABSTRACT

BACKGROUND: Reactivation of the telomerase reverse transcriptase gene TERT is a central feature for unlimited proliferation of the majority of cancers. However, the underlying regulatory processes are only partly understood. RESULTS: We assembled regulator binding information from serveral sources to construct a generic human and mouse gene regulatory network. Advancing our "Mixed Integer linear Programming based Regulatory Interaction Predictor" (MIPRIP) approach, we identified the most common and cancer-type specific regulators of TERT across 19 different human cancers. The results were validated by using the well-known TERT regulation by the ETS1 transcription factor in a subset of melanomas with mutations in the TERT promoter. Our improved MIPRIP2 R-package and the associated generic regulatory networks are freely available at https://github.com/KoenigLabNM/MIPRIP. CONCLUSION: MIPRIP 2.0 identified common as well as tumor type specific regulators of TERT. The software can be easily applied to transcriptome datasets to predict gene regulation for any gene and disease/condition under investigation.


Subject(s)
Gene Regulatory Networks , Neoplasms/genetics , Telomerase/genetics , User-Computer Interface , Animals , Humans , Melanoma/genetics , Melanoma/pathology , Mice , Mutation , Neoplasms/pathology , Promoter Regions, Genetic , Proto-Oncogene Protein c-ets-1/metabolism , Telomerase/metabolism
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