177 results on '"Heike L. Pahl"'
Search Results
2. LSD1 Inhibition Prolongs Survival in Mouse Models of MPN by Selectively Targeting the Disease Clone
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Jonas S. Jutzi, Maria Kleppe, Jennifer Dias, Hans Felix Staehle, Kaitlyn Shank, Julie Teruya-Feldstein, Sudheer Madan Mohan Gambheer, Christine Dierks, Hugh Y. Rienhoff, Jr, Ross L. Levine, and Heike L. Pahl
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Abstract. Despite recent advances, the myeloproliferative neoplasms (MPNs) are attended by considerable morbidity and mortality. Janus kinase (Jak) inhibitors such as ruxolitinib manage symptoms but do not substantially change the natural history of the disease. In this report, we show the effects of IMG-7289, an irreversible inhibitor of the epigenetically active lysine-specific demethylase 1 (LSD1) in mouse models of MPN. Once-daily treatment with IMG-7289 normalized or improved blood cell counts, reduced spleen volumes, restored normal splenic architecture, and reduced bone marrow fibrosis. Most importantly, LSD1 inhibition lowered mutant allele burden and improved survival. IMG-7289 selectively inhibited proliferation and induced apoptosis of JAK2V617F cells by concomitantly increasing expression and methylation of p53, and, independently, the pro-apoptotic factor PUMA and by decreasing the levels of its antiapoptotic antagonist BCLXL. These data provide a molecular understanding of the disease-modifying activity of the LSD1 inhibitor IMG-7289 that is currently undergoing clinical evaluation in patients with high-risk myelofibrosis. Moreover, low doses of IMG-7289 and ruxolitinib synergize in normalizing the MPN phenotype in mice, offering a rationale for investigating combination therapy.
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- 2018
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3. Associations between gender, disease features and symptom burden in patients with myeloproliferative neoplasms: an analysis by the MPN QOL International Working Group
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Holly L. Geyer, Heidi Kosiorek, Amylou C. Dueck, Robyn Scherber, Stefanie Slot, Sonja Zweegman, Peter AW te Boekhorst, Zhenya Senyak, Harry C. Schouten, Federico Sackmann, Ana Kerguelen Fuentes, Dolores Hernández-Maraver, Heike L. Pahl, Martin Griesshammer, Frank Stegelmann, Konstanze Döhner, Thomas Lehmann, Karin Bonatz, Andreas Reiter, Francoise Boyer, Gabriel Etienne, Jean-Christophe Ianotto, Dana Ranta, Lydia Roy, Jean-Yves Cahn, Claire N. Harrison, Deepti Radia, Pablo Muxi, Norman Maldonado, Carlos Besses, Francisco Cervantes, Peter L. Johansson, Tiziano Barbui, Giovanni Barosi, Alessandro M. Vannucchi, Chiara Paoli, Francesco Passamonti, Bjorn Andreasson, Maria L Ferrari, Alessandro Rambaldi, Jan Samuelsson, Keith Cannon, Gunnar Birgegard, Zhijian Xiao, Zefeng Xu, Yue Zhang, Xiujuan Sun, Junqing Xu, Jean-Jacques Kiladjian, Peihong Zhang, Robert Peter Gale, and Ruben A. Mesa
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
The myeloproliferative neoplasms, including polycythemia vera, essential thrombocythemia and myelofibrosis, are distinguished by their debilitating symptom profiles, life-threatening complications and profound impact on quality of life. The role gender plays in the symptomatology of myeloproliferative neoplasms remains under-investigated. In this study we evaluated how gender relates to patients’ characteristics, disease complications and overall symptom expression. A total of 2,006 patients (polycythemia vera=711, essential thrombocythemia=830, myelofibrosis=460, unknown=5) were prospectively evaluated, with patients completing the Myeloproliferative Neoplasm-Symptom Assessment Form and Brief Fatigue Inventory Patient Reported Outcome tools. Information on the individual patients’ characteristics, disease complications and laboratory data was collected. Consistent with known literature, most female patients were more likely to have essential thrombocythemia (48.6% versus 33.0%; P
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- 2017
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4. A novel role for nuclear factor-erythroid 2 in erythroid maturation by modulation of mitochondrial autophagy
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Monika Gothwal, Julius Wehrle, Konrad Aumann, Vanessa Zimmermann, Albert Gründer, and Heike L. Pahl
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
We have recently demonstrated that the transcription factor nuclear factor-erythroid 2, which is critical for erythroid maturation and globin gene expression, plays an important role in the pathophysiology of myeloproliferative neoplasms. Myeloproliferative neoplasm patients display elevated levels of nuclear factor-erythroid 2 and transgenic mice overexpressing the transcription factor develop myeloproliferative neoplasm, albeit, surprisingly without erythrocytosis. Nuclear factor-erythroid 2 transgenic mice show both a reticulocytosis and a concomitant increase in iron deposits in the spleen, suggesting both enhanced erythrocyte production and increased red blood cell destruction. We therefore hypothesized that elevated nuclear factor-erythroid 2 levels may lead to increased erythrocyte destruction by interfering with organelle clearance during erythroid maturation. We have previously shown that nuclear factor-erythroid 2 overexpression delays erythroid maturation of human hematopoietic stem cells. Here we report that increased nuclear factor-erythroid 2 levels also impede murine maturation by retarding mitochondrial depolarization and delaying mitochondrial elimination. In addition, ribosome autophagy is delayed in transgenics. We demonstrate that the autophagy genes NIX and ULK1 are direct novel nuclear factor-erythroid 2 target genes, as these loci are bound by nuclear factor-erythroid 2 in chromatin immunoprecipitation assays. Moreover, Nix and Ulk1 expression is increased in transgenic mice and in granulocytes from polycythemia vera patients. This is the first report implying a role for nuclear factor-erythroid 2 in erythroid maturation by affecting autophagy.
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- 2016
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5. The Hen or the Egg: Inflammatory Aspects of Murine MPN Models
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Jonas S. Jutzi and Heike L. Pahl
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Pathology ,RB1-214 - Abstract
It has been known for some time that solid tumors, especially gastrointestinal tumors, can arise on the basis of chronic inflammation. However, the role of inflammation in the genesis of hematological malignancies has not been extensively studied. Recent evidence clearly shows that changes in the bone marrow niche can suffice to induce myeloid diseases. Nonetheless, while it has been demonstrated that myeloproliferative neoplasms (MPN) are associated with a proinflammatory state, it is not clear whether inflammatory processes contribute to the induction or maintenance of MPN. More provocatively stated: which comes first, the hen or the egg, inflammation or MPN? In other words, can chronic inflammation itself trigger an MPN? In this review, we will describe the evidence supporting a role for inflammation in initiating and promoting MPN development. Furthermore, we will compare and contrast the data obtained in gastrointestinal tumors with observations in MPN patients and models, pointing out the opportunities provided by novel murine MPN models to address fundamental questions regarding the role of inflammatory stimuli in the molecular pathogenesis of MPN.
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- 2015
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6. NFE2 regulates transcription of multiple enzymes in the heme biosynthesis pathway
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Lara Rheinemann, Thalia S. Seeger, Julius Wehrle, and Heike L. Pahl
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Published
- 2014
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7. Transcription factor nuclear factor erythroid-2 mediates expression of the cytokine interleukin 8, a known predictor of inferior outcome in patients with myeloproliferative neoplasms
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Julius Wehrle, Thalia S. Seeger, Sven Schwemmers, Dietmar Pfeifer, Alla Bulashevska, and Heike L. Pahl
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
The transcription factor nuclear factor erythroid-2 is over-expressed in patients with myeloproliferative neoplasms irrespective of the presence of the JAK2V617F mutation. Our transgenic mouse model over-expressing nuclear factor erythroid-2, which recapitulates many features of myeloproliferative neoplasms including transformation to acute myeloid leukemia, clearly implicates this transcription factor in the pathophysiology of myeloproliferative neoplasms. Because the targets mediating nuclear factor erythroid-2 effects are not well characterized, we conducted microarray analysis of CD34+ cells lentivirally transduced to over-express nuclear factor erythroid-2 or to silence this transcription factor via shRNA, in order to identify novel target genes. Here, we report that the cytokine interleukin 8 is a novel target gene. Nuclear factor erythroid-2 directly binds the interleukin 8 promoter in vivo, and these binding sites are required for promoter activity. Serum levels of interleukin 8 are known to be elevated in both polycythemia vera and primary myelofibrosis patients. Recently, increased interleukin 8 levels have been shown to be predictive of inferior survival in primary myelofibrosis patients in multivariate analysis. Therefore, one of the mechanisms by which nuclear factor erythroid-2 contributes to myeloproliferative neoplasm pathology may be increased interleukin 8 expression.
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- 2013
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8. Molecular genetic analyses in familial and sporadic congenital primary erythrocytosis
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Susana Rives, Heike L. Pahl, Lourdes Florensa, Beatriz Bellosillo, Andrea Neusuess, Jesus Estella, Klaus-Michael Debatin, Elisabeth Kohne, Klaus Schwarz, and Holger Cario
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Dominant mutations in the erythropoietin receptor (EPOR) gene account for only about 15% of cases of primary congenital erythrocytosis. To search for molecular alterations in patients with this disorder. Sixteen patients with Epo
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- 2007
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9. Concomitant constitutive LNK and NFE2 mutation with loss of sumoylation in a case of hereditary thrombocythemia
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Wei Wang, Jan Breucker, Heike L. Pahl, Lukas Clemens Böckelmann, Albert Gründer, Andrea Pichler, Titiksha Basu, and Sandra Kaiser
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business.industry ,Essential thrombocythemia ,SUMO protein ,Hematology ,medicine.disease ,NFE2 ,Concomitant ,Mutation (genetic algorithm) ,Cancer research ,Medicine ,business ,Letters to the Editor ,Hereditary thrombocythemia ,Megakaryopoiesis - Published
- 2021
10. Enhanced expression of the sphingosine-1-phosphate-receptor-3 causes acute myelogenous leukemia in mice
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Christoph Koellerer, Albert Gründer, Mathijs A. Sanders, Manuela Simoni, Laura Riccetti, Heike L. Pahl, Jerzy-Roch Nofer, Peter J. M. Valk, Jonas S. Jutzi, Carsten Müller-Tidow, Fengbiao Zhou, Samuel Vorbach, Francesco Potì, and Hematology
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0301 basic medicine ,Cancer Research ,Mice, Transgenic ,Biology ,Mice ,03 medical and health sciences ,Myelogenous ,chemistry.chemical_compound ,0302 clinical medicine ,hemic and lymphatic diseases ,medicine ,Animals ,Humans ,Transgenes ,Receptor modulator ,Sphingosine-1-Phosphate Receptors ,Sphingosine 1-Phosphate Receptor 3 ,Sphingosine ,Fingolimod Hydrochloride ,Gene Expression Regulation, Leukemic ,Wild type ,Myeloid leukemia ,Hematology ,Hematopoietic Stem Cells ,medicine.disease ,Mice, Inbred C57BL ,Leukemia, Myeloid, Acute ,Haematopoiesis ,Leukemia ,030104 developmental biology ,Oncology ,chemistry ,030220 oncology & carcinogenesis ,Mutation ,Cancer research ,Transcriptome ,Signal Transduction - Abstract
Acute myeloid leukemia (AML) carries a 10–100 fold lower mutational burden than other neoplastic entities. Mechanistic explanations for why a low number of mutations suffice to induce leukemogenesis are therefore required. Here we demonstrate that transgenic overexpression of the wild type sphingosine-1-phosphate receptor 3 (S1P3) in murine hematopoietic stem cells is sufficient to induce a transplantable myeloid leukemia. In contrast, S1P3 expression in more mature compartments does not cause malignant transformation. Treatment with the sphingosine phosphate receptor modulator Fingolimod, which prevents receptor signaling, normalized peripheral blood cell counts and reduced spleen sizes in S1P3 expressing mice. Gene expression analyses in AML patients revealed elevated S1P3 expression specifically in two molecular subclasses. Our data suggest a previously unrecognized contribution of wild type S1P3 signaling to leukemogenesis that warrants the exploration of S1P3 antagonists in preclinical AML models.
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- 2020
11. Kidney dysfunction is associated with thrombosis and disease severity in myeloproliferative neoplasms: implications from the German Study Group for MPN Bioregistry
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Judith Gecht, Stefani Parmentier, Joachim R. Göthert, Mathias Hänel, Uwe Platzbecker, Tim H. Brümmendorf, Steffen Koschmieder, Christoph Maintz, Richard A. Hansen, Kim Kricheldorf, Martin Kirschner, Fabian Lang, Katja Sockel, Heike L. Pahl, Haifa Kathrin Al-Ali, Ioannis Tsoukakis, Susanne Isfort, Holger Schulz, Norbert Gattermann, Martin Griesshammer, Frank Stegelmann, Konstanze Döhner, Martin Bommer, Martine Klausmann, Florian H Heidel, and Wiebke Hollburg
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Cancer Research ,essential thrombocythemia (ET) ,Myeloproliferative sisorders ,Medizin ,JAK inhibition ,Gastroenterology ,chemistry.chemical_compound ,Polycythemia vera ,hemic and lymphatic diseases ,Neoplasms ,Venous thrombosis ,Platelet ,JAK2V617F ,Polycythemia Vera ,RC254-282 ,Renal insufficiency, Chronic ,%22">Krebs ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,food and beverages ,Thrombosis ,Cardiovascular diseases ,Oncology ,Thromboembolie ,Januskinase ,Nierenkrankheit ,medicine.medical_specialty ,Renal function ,Primäre Thrombozythämie ,Article ,C-reactive protein ,primary myelofibrosis (PMF) ,Internal medicine ,renal dysfunction ,Thromboembolism ,C-reaktives Protein ,medicine ,ddc:610 ,Myelofibrosis ,thrombosis ,Mortality risk ,Krebs ,business.industry ,Essential thrombocythemia ,bleeding ,medicine.disease ,chemistry ,Primary myelofibrosis ,polycythemia vera (PV) ,Janus kinases ,Uric acid ,myeloproliferative neoplasms (MPN) ,business ,DDC 610 / Medicine & health ,chronic kidney disease ,Kidney disease - Abstract
Inflammation-induced thrombosis represents a severe complication in patients with myeloproliferative neoplasms (MPN) and in those with kidney dysfunction. Overlapping disease-specific attributes suggest common mechanisms involved in MPN pathogenesis, kidney dysfunction, and thrombosis. Data from 1420 patients with essential thrombocythemia (ET, 33.7%), polycythemia vera (PV, 38.5%), and myelofibrosis (MF, 27.9%) were extracted from the bioregistry of the German Study Group for MPN. The total cohort was subdivided according to the calculated estimated glomerular filtration rate (eGFR, (mL/min/1.73 m2)) into eGFR1 (≥90, 21%), eGFR2 (60–89, 56%), and eGFR3 (<, 60, 22%). A total of 29% of the patients had a history of thrombosis. A higher rate of thrombosis and longer MPN duration was observed in eGFR3 than in eGFR2 and eGFR1. Kidney dysfunction occurred earlier in ET than in PV or MF. Multiple logistic regression analysis identified arterial hypertension, MPN treatment, increased uric acid, and lactate dehydrogenase levels as risk factors for kidney dysfunction in MPN patients. Risk factors for thrombosis included arterial hypertension, non-excessive platelet counts, and antithrombotic therapy. The risk factors for kidney dysfunction and thrombosis varied between MPN subtypes. Physicians should be aware of the increased risk for kidney disease in MPN patients, which warrants closer monitoring and, possibly, early thromboprophylaxis.
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- 2021
12. Strukturierte Karrierewege in der Universitätsmedizin
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Leena Bruckner-Tuderman, Karin Werner, Irene E. Nagel, Robert Thimme, and Heike L. Pahl
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Medical education ,Clinician scientist ,media_common.quotation_subject ,education ,MEDLINE ,General Medicine ,Career education ,030204 cardiovascular system & hematology ,Career Pathways ,03 medical and health sciences ,0302 clinical medicine ,Promotion (rank) ,030212 general & internal medicine ,Psychology ,Career choice ,media_common - Abstract
Scientifically active medical doctors are required for successful translation of novel basic findings into the clinic. However, there is an increasing tendency of young medical doctors to primarily follow a more clinically and not scientifically orientated career pathway. Therefore, the establishment of novel career education structures and career perspectives in university medicine are important to stop this development. Here, we will discuss the current situation and ongoing attempts to design novel structural programs that allow a better combination of clinical and scientific work by highlighting also current developments at the Faculty of Medicine at the University of Freiburg.
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- 2019
13. Altered NFE2 activity predisposes to leukemic transformation and myelosarcoma with AML-specific aberrations
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Mathijs A. Sanders, Sandra Kaiser, Wei Wang, Sarolta Bojtine Kovacs, Lars Bullinger, Bruno Cassinat, Annelieke Zeilemaker, Christoph Koellerer, Peter J. M. Valk, Jonas S. Jutzi, Titiksha Basu, Adil Al Hinai, Jenny Ostendorp, Brigitte Schlegelberger, Heike L. Pahl, Emmanuel Raffoux, Doris Steinemann, Maximilian Pellmann, Konrad Aumann, and Hematology
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Adult ,Male ,Myeloid ,Adolescent ,Immunology ,Trisomy 8 ,medicine.disease_cause ,Biochemistry ,Mice ,Young Adult ,hemic and lymphatic diseases ,Animals ,Humans ,Medicine ,Sarcoma, Myeloid ,Transcription factor ,Aged ,Aged, 80 and over ,Chromosome Aberrations ,Mutation ,Myeloid Neoplasia ,business.industry ,Myeloid leukemia ,Cell Biology ,Hematology ,Middle Aged ,medicine.disease ,Phenotype ,Leukemia, Myeloid, Acute ,Leukemia ,Cell Transformation, Neoplastic ,medicine.anatomical_structure ,NF-E2 Transcription Factor, p45 Subunit ,Cancer research ,Female ,Sarcoma ,Tumor Suppressor Protein p53 ,business - Abstract
In acute myeloid leukemia (AML), acquired genetic aberrations carry prognostic implications and guide therapeutic decisions. Clinical algorithms have been improved by the incorporation of novel aberrations. Here, we report the presence and functional characterization of mutations in the transcription factor NFE2 in patients with AML and in a patient with myelosarcoma. We previously described NFE2 mutations in patients with myeloproliferative neoplasms and demonstrated that expression of mutant NFE2 in mice causes a myeloproliferative phenotype. Now, we show that, during follow-up, 34% of these mice transform to leukemia presenting with or without concomitant myelosarcomas, or develop isolated myelosarcomas. These myelosarcomas and leukemias acquired AML-specific alterations, including the murine equivalent of trisomy 8, loss of the AML commonly deleted region on chromosome 5q, and mutations in the tumor suppressor Trp53. Our data show that mutations in NFE2 predispose to the acquisition of secondary changes promoting the development of myelosarcoma and/or AML.
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- 2019
14. Prevalence and characteristics of myeloproliferative neoplasms with concomitant monoclonal gammopathy
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Milena Pantic, Julius Wehrle, Sabine Bleul, Martin Werner, Justus Duyster, Valerie Hupfer, Konrad Aumann, Nikolas von Bubnoff, Dietmar Pfeifer, Cornelius F. Waller, Christoph Niemöller, Jürgen Finke, Gabriele Ihorst, Nora Rebeka Javorniczky, Monika Engelhardt, Heike L. Pahl, and Heiko Becker
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Immunofixation ,Adult ,Male ,Cancer Research ,medicine.medical_specialty ,Adolescent ,Population ,Gastroenterology ,Monoclonal Gammopathy of Undetermined Significance ,03 medical and health sciences ,0302 clinical medicine ,Polycythemia vera ,hemic and lymphatic diseases ,Internal medicine ,medicine ,Prevalence ,Humans ,education ,Child ,Multiple myeloma ,Myeloproliferative neoplasm ,Aged ,Aged, 80 and over ,education.field_of_study ,Myeloproliferative Disorders ,biology ,Essential thrombocythemia ,business.industry ,food and beverages ,Hematology ,Middle Aged ,medicine.disease ,Transplantation ,Oncology ,030220 oncology & carcinogenesis ,Concomitant ,Hematologic Neoplasms ,biology.protein ,Female ,business ,030215 immunology - Abstract
Of BCR-ABL negative myeloproliferative neoplasm (MPN) patients, 3-14 % display a concomitant monoclonal gammopathy (MGUS). Nonetheless, literature on co-occurring MPN and MGUS is scarce, the molecular underpinnings are unknown and it is unclear whether patients require a specific management. Here, we compared the clinical and genetic features of MPN patients with and without concomitant MGUS. Of 114 MPN patients prospectively studied by serum immunofixation (median age, 67 years; 36.0 % essential thrombocythemia [ET], 24.6 % polycythemia vera [PV], 11.4 % secondary myelofibrosis [sMF], 28.1 % primary myelofibrois [PMF]; 73.7 % JAK2 V617F positive), 10 (9 %) harbored an M-protein. No relevant clinical differences existed between MPN patients with or without M-protein. Seven additional MPN/MGUS patients were retrospectively identified in our MPN registry, yielding a total of 17 patients (7 ET, 3 PV, 3 sMF, 4 PMF). One patient developed multiple myeloma (MM) and one smoldering MM. Seven of 12 patients analyzed carried mutations (e.g. in ASXL1 or TET2) in addition to those in JAK2 or CALR, and 4 of 10 patients showed aberrant cytogenetics. M-protein was mainly IgG (12/17), followed by IgM (4/17). In the two patients that underwent allogeneic stem cell transplantation mutant JAK2 and M-protein were no longer detectable post-transplant. In conclusion, MGUS prevalence in our cohort was in the range of previous reports and at most slightly higher than expected in the general population. MGUS presence did not correlate with a specific MPN entity, clinical features or genetic alterations. Our observations suggest that there is no strong clinical or biological relationship between the occurrence of MGUS and MPN.
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- 2020
15. The transcription factor NFE2 enhances expression of the hematopoietic master regulators SCL/TAL1 and GATA2
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Laura C. Siegwart, Thalia S. Seeger, Julius Wehrle, Sven Schwemmers, Albert Gründer, Heike L. Pahl, and Christoph Koellerer
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0301 basic medicine ,Cancer Research ,NF-E2 Transcription Factor ,Biology ,NFE2 ,03 medical and health sciences ,0302 clinical medicine ,Genetics ,Humans ,Molecular Biology ,Transcription factor ,T-Cell Acute Lymphocytic Leukemia Protein 1 ,Regulation of gene expression ,Myeloproliferative Disorders ,GATA2 ,Cell Biology ,Hematology ,Phenotype ,GATA2 Transcription Factor ,Gene Expression Regulation, Neoplastic ,Haematopoiesis ,030104 developmental biology ,030220 oncology & carcinogenesis ,Hematologic Neoplasms ,NF-E2 Transcription Factor, p45 Subunit ,Cancer research ,TAL1 - Abstract
Activity of the transcription factor NFE2 is elevated in the majority of patients with myeloproliferative neoplasms (MPNs), either by overexpression of the wild-type alleles or by the presence of an activating mutation. In murine models, enhanced NFE2 activity causes an MPN phenotype with spontaneous transformation to acute leukemia. However, little is known about the downstream target genes activated by augmented NFE2 levels. Here, we describe that NFE2 regulates expression of the hematopoietic master regulators GATA2 and SCL/TAL1, which are in turn overexpressed in primary MPN cells, suggesting that concomitant aberrant activation of several transcription factors coordinately contributes to the cellular expansion characteristic of these disorders.
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- 2020
16. Jmjd1c is dispensable for healthy adult hematopoiesis and Jak2V617F-driven myeloproliferative disease initiation in mice
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Johannes Heinemann, Hans F. Staehle, Jonas S. Jutzi, Anne M. Omlor, Albert Gruender, and Heike L. Pahl
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0301 basic medicine ,Male ,Embryology ,Jumonji Domain-Containing Histone Demethylases ,Physiology ,Hematologic Cancers and Related Disorders ,Gene Knockout Techniques ,Mice ,0302 clinical medicine ,Medicine and Health Sciences ,Femur ,Musculoskeletal System ,Staining ,Mice, Knockout ,Multidisciplinary ,biology ,food and beverages ,Cell Staining ,Animal Models ,Hematology ,Phenotype ,Body Fluids ,Haematopoiesis ,Leukemia ,Histone ,Blood ,Experimental Organism Systems ,Oncology ,030220 oncology & carcinogenesis ,Knockout mouse ,Medicine ,Stem cell ,Anatomy ,Research Article ,Science ,Embryonic Development ,Mouse Models ,DNA construction ,Research and Analysis Methods ,03 medical and health sciences ,Myeloproliferative Disorders ,Model Organisms ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Molecular Biology Techniques ,Molecular Biology ,Skeleton ,DNA manipulations ,Embryos ,Biology and Life Sciences ,Cancers and Neoplasms ,Janus Kinase 2 ,medicine.disease ,Exon Trapping ,Hematopoiesis ,Blood Counts ,030104 developmental biology ,Specimen Preparation and Treatment ,Case-Control Studies ,Mutation ,biology.protein ,Cancer research ,Animal Studies ,Demethylase ,Developmental Biology ,Cloning - Abstract
The histone demethylase JMJD1C is overexpressed in patients with myeloproliferative neoplasms (MPNs) and has been implicated in leukemic stem cell function of MLL-AF9 and HOXA9-driven leukemia. In the emerging field of histone demethylase inhibitors, JMJD1C therefore became a potential target. Depletion of Jmjd1c expression significantly reduced cytokine-independent growth in an MPN cell line, indicating a role for JMJD1C in MPN disease maintenance. Here, we investigated a potential role for the demethylase in MPN disease initiation. We introduced a Cre-inducible JAK2V617F mutation into Jmjd1c knockout mice. We show that Jmjd1c is dispensable, both for healthy hematopoiesis as well as for JAK2V617F-driven MPN disease initiation. Jmjd1c knockout mice did not show any significant changes in peripheral blood composition. Likewise, introduction of JAK2V617F into Jmjd1c-/- mice led to a similar MPN phenotype as JAK2V617F in a Jmjd1c wt background. This indicates that there is a difference between the role of JMJD1C in leukemic stem cells and in MPN. In the latter, JMJC domain-containing family members may serve redundant roles, compensating for the loss of individual proteins.
- Published
- 2020
17. Water pipe smoking as a cause of secondary erythrocytosis
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Heiko Becker, Nikolas von Bubnoff, Cornelius F. Waller, Nora Rebeka Javorniczky, and Heike L. Pahl
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Pediatrics ,medicine.medical_specialty ,business.industry ,Case Report ,030204 cardiovascular system & hematology ,Microbiology ,03 medical and health sciences ,0302 clinical medicine ,Infectious Diseases ,Water Pipe Smoking ,Younger adults ,Male patient ,Water pipe ,Medicine ,Parasitology ,030212 general & internal medicine ,Secondary erythrocytosis ,business - Abstract
Water pipe (WP) smoking has become very popular in European countries. A 27-year-old male patient was referred to our clinic with erythrocytosis of unknown origin. His self-reported history included almost daily WP smoking since the age of 14 years. At presentation haemoglobin, haematocrit (Hct) and carboxy-haemoglobin (CO-Hb) levels were elevated to 19.7 g/dl, 54% and 15.4%, respectively. Erythrocytosis was completely reversible upon cessation of WP smoking. Upon follow-up, haemoglobin, Hct and CO-Hb levels undulated according to the intensity of WP usage. Our report shall raise awareness among physicians for WP smoking as a possible cause of secondary erythrocytosis, particularly among younger adults, and provide guidance for the clinical management.
- Published
- 2019
18. [Structured Career Pathways in the University Medicine - From Promotion to Clinician Scientist Programs]
- Author
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Robert, Thimme, Heike L, Pahl, Karin, Werner, Irene E, Nagel, and Leena, Bruckner-Tuderman
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Biomedical Research ,Career Choice ,Education, Medical ,Universities ,Humans ,Medicine ,Schools, Medical - Abstract
Scientifically active medical doctors are required for successful translation of novel basic findings into the clinic. However, there is an increasing tendency of young medical doctors to primarily follow a more clinically and not scientifically orientated career pathway. Therefore, the establishment of novel career education structures and career perspectives in university medicine are important to stop this development. Here, we will discuss the current situation and ongoing attempts to design novel structural programs that allow a better combination of clinical and scientific work by highlighting also current developments at the Faculty of Medicine at the University of Freiburg.
- Published
- 2019
19. Gab2 is Essential for Transformation by FLT3-ITD in Acute Myeloid Leukemia
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Heiko Becker, Tilman Brummer, Albert Gründer, Sebastian Halbach, Heike L. Pahl, Franziska M. Uhl, Julia Huber, Rumyana Todorova, Robert Zeiser, Corinna Spohr, Konrad Aumann, and Katharina Sies
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Transformation (genetics) ,Letter ,lcsh:RC633-647.5 ,Cancer research ,biology.protein ,Myeloid leukemia ,GAB2 ,Hematology ,lcsh:Diseases of the blood and blood-forming organs ,Biology ,Flt3 itd - Published
- 2019
20. Phase II trial of Lestaurtinib, a JAK2 inhibitor, in patients with myelofibrosis
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Maria R. Baer, John Mascarenhas, Elizabeth O. Hexner, Ronald Hoffman, Lonette Sandy, Craig M. Kessler, Judith D. Goldberg, Douglas Tremblay, Leah Price, Heike L. Pahl, Amylou C. Dueck, Heidi E. Kosiorek, Rona Singer Weinberg, and Lewis R. Silverman
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Cancer Research ,Lestaurtinib ,business.industry ,fungi ,Treatment outcome ,food and beverages ,Myeloid leukemia ,Bone marrow fibrosis ,Hematology ,Myeloid proliferation ,medicine.disease ,Article ,03 medical and health sciences ,0302 clinical medicine ,Oncology ,hemic and lymphatic diseases ,030220 oncology & carcinogenesis ,Cancer research ,medicine ,In patient ,Myelofibrosis ,business ,Myeloproliferative neoplasm ,030215 immunology ,medicine.drug - Abstract
Myelofibrosis (MF) is a myeloproliferative neoplasm (MPN) characterized by bone marrow fibrosis and clonal myeloid proliferation which can eventually evolve into acute myeloid leukemia. Dysregulate...
- Published
- 2019
21. A novel role for nuclear factor-erythroid 2 in erythroid maturation by modulation of mitochondrial autophagy
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Albert Gründer, Konrad Aumann, Heike L. Pahl, Julius Wehrle, Vanessa Zimmermann, and Monika Gothwal
- Subjects
0301 basic medicine ,Reticulocytes ,Transgene ,Gene Expression ,Mice, Transgenic ,Mitochondrion ,Biology ,Immunophenotyping ,Mice ,03 medical and health sciences ,Erythroid Cells ,NF-E2 Transcription Factor ,hemic and lymphatic diseases ,Gene expression ,Autophagy ,medicine ,Animals ,Humans ,Erythropoiesis ,Polycythemia Vera ,Transcription factor ,Myeloproliferative neoplasm ,Membrane Potential, Mitochondrial ,Articles ,Hematology ,medicine.disease ,Molecular biology ,Mitochondria ,Phenylhydrazines ,Cell biology ,Haematopoiesis ,030104 developmental biology ,Gene Expression Regulation ,Stem cell ,Ribosomes ,Biomarkers - Abstract
We have recently demonstrated that the transcription factor nuclear factor-erythroid 2, which is critical for erythroid maturation and globin gene expression, plays an important role in the pathophysiology of myeloproliferative neoplasms. Myeloproliferative neoplasm patients display elevated levels of nuclear factor-erythroid 2 and transgenic mice overexpressing the transcription factor develop myeloproliferative neoplasm, albeit, surprisingly without erythrocytosis. Nuclear factor-erythroid 2 transgenic mice show both a reticulocytosis and a concomitant increase in iron deposits in the spleen, suggesting both enhanced erythrocyte production and increased red blood cell destruction. We therefore hypothesized that elevated nuclear factor-erythroid 2 levels may lead to increased erythrocyte destruction by interfering with organelle clearance during erythroid maturation. We have previously shown that nuclear factor-erythroid 2 overexpression delays erythroid maturation of human hematopoietic stem cells. Here we report that increased nuclear factor-erythroid 2 levels also impede murine maturation by retarding mitochondrial depolarization and delaying mitochondrial elimination. In addition, ribosome autophagy is delayed in transgenics. We demonstrate that the autophagy genes NIX and ULK1 are direct novel nuclear factor-erythroid 2 target genes, as these loci are bound by nuclear factor-erythroid 2 in chromatin immunoprecipitation assays. Moreover, Nix and Ulk1 expression is increased in transgenic mice and in granulocytes from polycythemia vera patients. This is the first report implying a role for nuclear factor-erythroid 2 in erythroid maturation by affecting autophagy.
- Published
- 2016
22. Myeloproliferative neoplasms and inflammation: whether to target the malignant clone or the inflammatory process or both
- Author
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Hans Carl Hasselbalch, Tiziano Barbui, A. Maria Vannucchi, Tariq I. Mughal, Steffen Koschmieder, Heike L. Pahl, Richard T. Silver, G Barosi, Georg Jeryczynski, Jonas S. Jutzi, Francisco Cervantes, J J Kiladjian, Heinz Gisslinger, Peter Valent, and Ruediger Hehlmann
- Subjects
0301 basic medicine ,Cancer Research ,medicine.medical_specialty ,Anti-Inflammatory Agents ,Inflammation ,Pathogenesis ,03 medical and health sciences ,0302 clinical medicine ,Myeloproliferative Disorders ,Neoplasms ,Internal medicine ,Humans ,Medicine ,Progenitor cell ,Hematology ,business.industry ,medicine.disease ,Clone Cells ,Leukemia ,030104 developmental biology ,Oncology ,030220 oncology & carcinogenesis ,Immunology ,medicine.symptom ,Stem cell ,business ,Clone (B-cell biology) - Abstract
The Philadelphia-negative myeloproliferative neoplasms (MPNs) are clonal disorders involving hematopoietic stem and progenitor cells and are associated with myeloproliferation, splenomegaly and constitutional symptoms. Similar signs and symptoms can also be found in patients with chronic inflammatory diseases, and inflammatory processes have been found to play an important role in the pathogenesis and progression of MPNs. Signal transduction pathways involving JAK1, JAK2, STAT3 and STAT5 are causally involved in driving both the malignant cells and the inflammatory process. Moreover, anti-inflammatory and immune-modulating drugs have been used successfully in the treatment of MPNs. However, to date, many unresoved issues remain. These include the role of somatic mutations that are present in addition to JAK2V617F, CALR and MPL W515 mutations, the interdependency of malignant and nonmalignant cells and the means to eradicate MPN-initiating and -maintaining cells. It is imperative for successful therapeutic approaches to define whether the malignant clone or the inflammatory cells or both should be targeted. The present review will cover three aspects of the role of inflammation in MPNs: inflammatory states as important differential diagnoses in cases of suspected MPN (that is, in the absence of a clonal marker), the role of inflammation in MPN pathogenesis and progression and the use of anti-inflammatory drugs for MPNs. The findings emphasize the need to separate the inflammatory processes from the malignancy in order to improve our understanding of the pathogenesis, diagnosis and treatment of patients with Philadelphia-negative MPNs.
- Published
- 2016
23. Ptch2 loss drives myeloproliferation and myeloproliferative neoplasm progression
- Author
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Anabel Zwick, Christine Dierks, Robert A.J. Oostendorp, Dietmar Pfeifer, Sarah Decker, Anna Lena Illert, Sandra Kissel, Justus Duyster, Heike L. Pahl, Marie Follo, Claudius Klein, Konrad Aumann, Thomas Benkler, and Christine Ulrike Forster
- Subjects
Patched Receptors ,0301 basic medicine ,JAG1 ,Immunology ,Mice, Transgenic ,Receptors, Cell Surface ,Ligands ,Patched-2 Receptor ,Article ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Myeloproliferative Disorders ,Lymphopenia ,Myeloproliferation ,medicine ,Animals ,Humans ,Immunology and Allergy ,Hedgehog Proteins ,Leukocytosis ,Stem Cell Niche ,Polycythemia Vera ,Research Articles ,Myeloproliferative neoplasm ,Mice, Knockout ,Leukemia ,Osteoblasts ,Janus kinase 2 ,biology ,Cell Biology ,Janus Kinase 2 ,Hematopoietic Stem Cells ,medicine.disease ,Recombinant Proteins ,Hematopoiesis ,Haematopoiesis ,Phenotype ,030104 developmental biology ,030220 oncology & carcinogenesis ,Disease Progression ,biology.protein ,Cancer research ,Mutant Proteins ,medicine.symptom ,Signal Transduction - Abstract
Klein et al. show that Ptch2 loss in either the niche or in hematopoietic cells drives myeloproliferation and accelerates JAK2V617F-driven pathogenesis, causing transformation of nonlethal chronic MPNs into aggressive lethal leukemias., JAK2V617F+ myeloproliferative neoplasms (MPNs) frequently progress into leukemias, but the factors driving this process are not understood. Here, we find excess Hedgehog (HH) ligand secretion and loss of PTCH2 in myeloproliferative disease, which drives canonical and noncanonical HH-signaling. Interestingly, Ptch2−/− mice mimic dual pathway activation and develop a MPN-phenotype with leukocytosis (neutrophils and monocytes), strong progenitor and LKS mobilization, splenomegaly, anemia, and loss of lymphoid lineages. HSCs exhibit increased cell cycling with improved stress hematopoiesis after 5-FU treatment, and this results in HSC exhaustion over time. Cytopenias, LKS loss, and mobilization are all caused by loss of Ptch2 in the niche, whereas hematopoietic loss of Ptch2 drives leukocytosis and promotes LKS maintenance and replating capacity in vitro. Ptch2−/− niche cells show hyperactive noncanonical HH signaling, resulting in reduced production of essential HSC regulators (Scf, Cxcl12, and Jag1) and depletion of osteoblasts. Interestingly, Ptch2 loss in either the niche or in hematopoietic cells dramatically accelerated human JAK2V617F-driven pathogenesis, causing transformation of nonlethal chronic MPNs into aggressive lethal leukemias with >30% blasts in the peripheral blood. Our findings suggest HH ligand inhibitors as possible drug candidates that act on hematopoiesis and the niche to prevent transformation of MPNs into leukemias.
- Published
- 2016
24. LSD1 Inhibition Prolongs Survival in Mouse Models of MPN by Selectively Targeting the Disease Clone
- Author
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Jennifer Dias, Kaitlyn Shank, Maria Kleppe, Julie Teruya-Feldstein, Sudheer Madan Mohan Gambheer, Hans F. Staehle, Hugh Y. Rienhoff, Jonas S. Jutzi, Heike L. Pahl, Ross L. Levine, and Christine Dierks
- Subjects
0301 basic medicine ,Ruxolitinib ,Combination therapy ,Clone (cell biology) ,Spleen ,Blood cell ,03 medical and health sciences ,0302 clinical medicine ,Puma ,medicine ,Myelofibrosis ,biology ,business.industry ,lcsh:RC633-647.5 ,Articles ,Hematology ,lcsh:Diseases of the blood and blood-forming organs ,biology.organism_classification ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,ComputingMethodologies_DOCUMENTANDTEXTPROCESSING ,Cancer research ,Janus kinase ,business ,medicine.drug - Abstract
Supplemental Digital Content is available in the text, Despite recent advances, the myeloproliferative neoplasms (MPNs) are attended by considerable morbidity and mortality. Janus kinase (Jak) inhibitors such as ruxolitinib manage symptoms but do not substantially change the natural history of the disease. In this report, we show the effects of IMG-7289, an irreversible inhibitor of the epigenetically active lysine-specific demethylase 1 (LSD1) in mouse models of MPN. Once-daily treatment with IMG-7289 normalized or improved blood cell counts, reduced spleen volumes, restored normal splenic architecture, and reduced bone marrow fibrosis. Most importantly, LSD1 inhibition lowered mutant allele burden and improved survival. IMG-7289 selectively inhibited proliferation and induced apoptosis of JAK2 V617F cells by concomitantly increasing expression and methylation of p53, and, independently, the pro-apoptotic factor PUMA and by decreasing the levels of its antiapoptotic antagonist BCLXL. These data provide a molecular understanding of the disease-modifying activity of the LSD1 inhibitor IMG-7289 that is currently undergoing clinical evaluation in patients with high-risk myelofibrosis. Moreover, low doses of IMG-7289 and ruxolitinib synergize in normalizing the MPN phenotype in mice, offering a rationale for investigating combination therapy.
- Published
- 2018
25. Gene mutations and clonal architecture in myelodysplastic syndromes and changes upon progression to acute myeloid leukaemia and under treatment
- Author
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Katarzyna Szarc vel Szic, Marie Follo, Heike L. Pahl, Julian Riba, Juliane M. Stosch, Heiko Becker, Nathalie Renz, Dietmar Pfeifer, Maja Rothenberg-Thurley, Klaus H. Metzeler, Julius Wehrle, Rainer Claus, Justus Duyster, Sabine Bleul, Stefan Zimmermann, Michael Lübbert, Anezka Heumüller, and Christoph Niemöller
- Subjects
0301 basic medicine ,Adult ,Male ,Gene mutation ,Biology ,03 medical and health sciences ,0302 clinical medicine ,hemic and lymphatic diseases ,medicine ,Humans ,Epigenetics ,Gene ,Genetics ,Myelodysplastic syndromes ,Hematology ,Methylation ,DNA Methylation ,Middle Aged ,medicine.disease ,Clone Cells ,Leukemia, Myeloid, Acute ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Myelodysplastic Syndromes ,DNA methylation ,Mutation ,Disease Progression ,Female ,Bone marrow ,Single-Cell Analysis ,Clonal selection - Abstract
Knowledge of the molecular and clonal characteristics in the myelodysplastic syndromes (MDS) and during progression to acute myeloid leukaemia (AML) is essential to understand the disease dynamics and optimize treatment. Sequencing serial bone marrow samples of eight patients, we observed that MDS featured a median of 3 mutations. Mutations in genes involved in RNA-splicing or epigenetic regulation were most frequent, and exclusively present in the major clone. Minor subclones were distinguishable in three patients. As the MDS progressed, a median of one mutation was gained, leading to clonal outgrowth. No AML developed genetically independent of a pre-existing clone. The gained mutation mostly affected genes encoding signalling proteins. Additional acquisition of genomic aberrations frequently occurred. Upon treatment, emergence of new clones could be observed. As confirmed by single-cell sequencing, multiple mutations in identical genes in different clones were present within individual patients. DNA-methylation profiling in patients without identification of novel mutations in AML revealed methylation changes in individual genes. In conclusion, our data complement previous observations on the mutational and clonal characteristics in MDS and at progression. Moreover, DNA-methylation changes may be associated with progression in single patients. Redundancy of mutated genes in different clones suggests fertile grounds promoting clonal selection or acquisition.
- Published
- 2018
26. Oncogenic JAK2 V617F causes PD-L1 expression, mediating immune escape in myeloproliferative neoplasms
- Author
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Khalid Shoumariyeh, Robert Zeiser, Sivahari P. Gorantla, Sebastian Halbach, Frederike A. Hartl, Alica J. Emhardt, Julius Wehrle, Jonas S. Jutzi, Sebastian Fuchs, Ioanna Triviai, Sandra Duquesne, Michael Hettich, Annette Schmitt-Graeff, Eliana Ruggiero, Susana Minguet, Wolfgang Melchinger, Jürgen Finke, Chiara Bonini, Nicolaus Kröger, Pia Veratti, Anna Lena Illert, Bruce R. Blazar, Melanie Boerries, Mark Bartholomä, Teresa Poggio, Geoffrey R. Hill, Steven W. Lane, Gabriele Niedermann, Petya Apostolova, Slavica Vuckovic, Nikolas von Bubnoff, Konrad Aumann, Hauke Busch, Stephan Ehl, Florian H. Heidel, Sandra Pennisi, Dietmar Pfeifer, Justus Duyster, Cornelius Miething, David O’Sullivan, Marie Follo, Lukas Braun, Christine Dierks, Heiko Becker, Heike L. Pahl, Jan Rohr, Tilman Brummer, Alessandro Prestipino, Erika L. Pearce, Prestipino, Alessandro, Emhardt, Alica J, Aumann, Konrad, O'Sullivan, David, Gorantla, Sivahari P, Duquesne, Sandra, Melchinger, Wolfgang, Braun, Luka, Vuckovic, Slavica, Boerries, Melanie, Busch, Hauke, Halbach, Sebastian, Pennisi, Sandra, Poggio, Teresa, Apostolova, Petya, Veratti, Pia, Hettich, Michael, Niedermann, Gabriele, Bartholomä, Mark, Shoumariyeh, Khalid, Jutzi, Jonas S, Wehrle, Juliu, Dierks, Christine, Becker, Heiko, Schmitt-Graeff, Annette, Follo, Marie, Pfeifer, Dietmar, Rohr, Jan, Fuchs, Sebastian, Ehl, Stephan, Hartl, Frederike A, Minguet, Susana, Miething, Corneliu, Heidel, Florian H, Kröger, Nicolau, Triviai, Ioanna, Brummer, Tilman, Finke, Jürgen, Illert, Anna L, Ruggiero, Eliana, Bonini, Chiara, Duyster, Justu, Pahl, Heike L, Lane, Steven W, Hill, Geoffrey R, Blazar, Bruce R, von Bubnoff, Nikola, Pearce, Erika L, and Zeiser, Robert
- Subjects
0301 basic medicine ,Janus kinase 2 ,Myeloid ,biology ,T cell ,food and beverages ,General Medicine ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,hemic and lymphatic diseases ,030220 oncology & carcinogenesis ,biology.protein ,medicine ,STAT protein ,Cancer research ,Receptor ,STAT3 ,STAT5 ,K562 cells - Abstract
Recent evidence has revealed that oncogenic mutations may confer immune escape. A better understanding of how an oncogenic mutation affects immunosuppressive programmed death ligand 1 (PD-L1) expression may help in developing new therapeutic strategies. We show that oncogenic JAK2 (Janus kinase 2) activity caused STAT3 (signal transducer and activator of transcription 3) and STAT5 phosphorylation, which enhanced PD-L1 promoter activity and PD-L1 protein expression in JAK2V617F-mutant cells, whereas blockade of JAK2 reduced PD-L1 expression in myeloid JAK2V617F-mutant cells. PD-L1 expression was higher on primary cells isolated from patients with JAK2V617F–myeloproliferative neoplasms (MPNs) compared to healthy individuals and declined upon JAK2 inhibition. JAK2V617F mutational burden, pSTAT3, and PD-L1 expression were highest in primary MPN patient–derived monocytes, megakaryocytes, and platelets. PD-1 (programmed death receptor 1) inhibition prolonged survival in human MPN xenograft and primary murine MPN models. This effect was dependent on T cells. Mechanistically, PD-L1 surface expression in JAK2V617F-mutant cells affected metabolism and cell cycle progression of T cells. In summary, we report that in MPN, constitutive JAK2/STAT3/STAT5 activation, mainly in monocytes, megakaryocytes, and platelets, caused PD-L1–mediated immune escape by reducing T cell activation, metabolic activity, and cell cycle progression. The susceptibility of JAK2V617F-mutant MPN to PD-1 targeting paves the way for immunomodulatory approaches relying on PD-1 inhibition.
- Published
- 2018
27. PS1454 CAG PROMOTER DRIVEN C-MYC OVEREXPRESSION CAUSES RAPIDLY LETHAL CARDIOMYOPATHY
- Author
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Titiksha Basu, S. Bojtine Kovacs, and Heike L. Pahl
- Subjects
Cardiomyopathy ,medicine ,Cancer research ,Hematology ,Biology ,medicine.disease - Published
- 2019
28. Epigenetic regulation of NFE2 overexpression in myeloproliferative neoplasms
- Author
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Jonas S. Jutzi, Christopher J. Ott, Christoph Koellerer, Albert Gründer, Jan C. Peeken, Heike L. Pahl, Thalia S. Seeger, Heiko Becker, Julius Wehrle, Hans F. Staehle, Monika Gothwal, Elias Schoenwandt, and Daniel H. Schanne
- Subjects
0301 basic medicine ,Jumonji Domain-Containing Histone Demethylases ,Immunology ,Gene Expression ,Decitabine ,Biochemistry ,Models, Biological ,NFE2 ,Epigenesis, Genetic ,Histones ,03 medical and health sciences ,Gene expression ,Humans ,Epigenetics ,Phosphorylation ,Promoter Regions, Genetic ,Transcription factor ,Polycythemia Vera ,Regulation of gene expression ,Myeloproliferative Disorders ,biology ,Chemistry ,Oxidoreductases, N-Demethylating ,Cell Biology ,Hematology ,DNA Methylation ,Janus Kinase 2 ,030104 developmental biology ,Histone ,Gene Expression Regulation ,Chromobox Protein Homolog 5 ,NF-E2 Transcription Factor, p45 Subunit ,DNA methylation ,Mutation ,biology.protein ,Cancer research ,Demethylase ,Cytokines ,Biomarkers ,Protein Binding - Abstract
The transcription factor "nuclear factor erythroid 2" (NFE2) is overexpressed in the majority of patients with myeloproliferative neoplasms (MPNs). In murine models, elevated NFE2 levels cause an MPN phenotype with spontaneous leukemic transformation. However, both the molecular mechanisms leading to NFE2 overexpression and its downstream targets remain incompletely understood. Here, we show that the histone demethylase JMJD1C constitutes a novel NFE2 target gene. JMJD1C levels are significantly elevated in polycythemia vera (PV) and primary myelofibrosis patients; concomitantly, global H3K9me1 and H3K9me2 levels are significantly decreased. JMJD1C binding to the NFE2 promoter is increased in PV patients, decreasing both H3K9me2 levels and binding of the repressive heterochromatin protein-1α (HP1α). Hence, JMJD1C and NFE2 participate in a novel autoregulatory loop. Depleting JMJD1C expression significantly reduced cytokine-independent growth of an MPN cell line. Independently, NFE2 is regulated through the epigenetic JAK2 pathway by phosphorylation of H3Y41. This likewise inhibits HP1α binding. Treatment with decitabine lowered H3Y41ph and augmented H3K9me2 levels at the NFE2 locus in HEL cells, thereby increasing HP1α binding, which normalized NFE2 expression selectively in JAK2V617F-positive cell lines.
- Published
- 2017
29. The oligodendrocyte lineage transcription factor 2 (OLIG2) is epigenetically regulated in acute myeloid leukemia
- Author
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Michael Lübbert, Marlon Kovarbasic, Björn Hackanson, Konstanze Döhner, Julius Wehrle, Ralph Wäsch, Heiko Becker, Mahmoud Abdelkarim, Arzu Yalcin, Lars Bullinger, Andrea Schmidts, Heike L. Pahl, Verena I. Gaidzik, Rainer Claus, and Justus Duyster
- Subjects
0301 basic medicine ,Cancer Research ,Blotting, Western ,Decitabine ,HL-60 Cells ,Biology ,Jurkat cells ,Epigenesis, Genetic ,OLIG2 ,03 medical and health sciences ,chemistry.chemical_compound ,Jurkat Cells ,0302 clinical medicine ,hemic and lymphatic diseases ,Cell Line, Tumor ,Genetics ,medicine ,Humans ,Molecular Biology ,Cell Proliferation ,Regulation of gene expression ,Gene Expression Regulation, Leukemic ,Reverse Transcriptase Polymerase Chain Reaction ,Myeloid leukemia ,Cell Differentiation ,Cell Biology ,Hematology ,U937 Cells ,DNA Methylation ,Oligodendrocyte Transcription Factor 2 ,medicine.disease ,Demethylating agent ,Leukemia ,030104 developmental biology ,chemistry ,Leukemia, Myeloid ,030220 oncology & carcinogenesis ,DNA methylation ,Acute Disease ,Cancer research ,Azacitidine ,RNA Interference ,medicine.drug - Abstract
DNA methylation differences between normal tissue and cancerous tissue resulting in differential expression of genes are a hallmark of acute myeloid leukemia (AML) and can provide malignant cells with a growth advantage via silencing of specific genes, for example, transcription factors. Oligodendrocyte lineage transcription factor 2 (OLIG2) was reported to be differentially methylated and associated with prognosis in AML and, as reported for acute lymphoblastic leukemia and malignant glioma, may play a role in malignant transformation. We report that DNA methylation of OLIG2 is associated with decreased expression of mRNA in AML cell lines and patients. Moreover, in cell lines, decreased mRNA expression also translated into decreased OLIG2 protein expression. Treatment of non-expressing cell lines PL-21 and U-937 with the demethylating agent decitabine resulted in robust re-expression of OLIG2 on mRNA and protein levels. Furthermore, stable overexpression of OLIG2 in non-expressing cell lines Kasumi-1 and U-937, using a lentiviral vector system, led to moderate growth inhibition after 4 days and resulted in signs of differentiation in U-937 cells. Interestingly, although CD34 + cells from healthy donors and 10 of 12 AML patients exhibited no protein expression, OLIG2 was expressed in two patients, both bearing the translocation t(15;17), corresponding to OLIG2 expression in NB-4 cells, also harboring t(15;17). In conclusion, we provide first evidence that OLIG2 is epigenetically regulated via DNA methylation and expressed in a subset of AML patients. OLIG2 may exert antiproliferative activity in leukemia cell lines, and its potential leukemia-suppressing role in AML warrants further investigation.
- Published
- 2017
30. Oncogenic JAK2
- Author
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Alessandro, Prestipino, Alica J, Emhardt, Konrad, Aumann, David, O'Sullivan, Sivahari P, Gorantla, Sandra, Duquesne, Wolfgang, Melchinger, Lukas, Braun, Slavica, Vuckovic, Melanie, Boerries, Hauke, Busch, Sebastian, Halbach, Sandra, Pennisi, Teresa, Poggio, Petya, Apostolova, Pia, Veratti, Michael, Hettich, Gabriele, Niedermann, Mark, Bartholomä, Khalid, Shoumariyeh, Jonas S, Jutzi, Julius, Wehrle, Christine, Dierks, Heiko, Becker, Annette, Schmitt-Graeff, Marie, Follo, Dietmar, Pfeifer, Jan, Rohr, Sebastian, Fuchs, Stephan, Ehl, Frederike A, Hartl, Susana, Minguet, Cornelius, Miething, Florian H, Heidel, Nicolaus, Kröger, Ioanna, Triviai, Tilman, Brummer, Jürgen, Finke, Anna L, Illert, Eliana, Ruggiero, Chiara, Bonini, Justus, Duyster, Heike L, Pahl, Steven W, Lane, Geoffrey R, Hill, Bruce R, Blazar, Nikolas, von Bubnoff, Erika L, Pearce, and Robert, Zeiser
- Subjects
Myeloproliferative Disorders ,food and beverages ,Janus Kinase 2 ,B7-H1 Antigen ,Article ,Mice ,Cell Transformation, Neoplastic ,hemic and lymphatic diseases ,Hematologic Neoplasms ,Tumor Cells, Cultured ,Animals ,Humans ,K562 Cells ,Cell Proliferation ,Signal Transduction - Abstract
Recent evidence has revealed that oncogenic mutations may confer immune escape. A better understanding of how an oncogenic mutation affects immunosuppressive PD-L1 expression may help in developing new therapeutic strategies. Here, we show that oncogenic JAK2 activity caused STAT3 and STAT5 phosphorylation, which enhanced PD-L1 promoter activity and PD-L1 protein expression in JAK2(V617F)-mutant cells, whereas blockade of JAK2 reduced PD-L1 expression in myeloid JAK2(V617F)-mutant cells. PD-L1 expression was higher on primary cells isolated from patients with JAK2(V617F)-myeloproliferative neoplasms (MPN) compared to healthy individuals and declined upon JAK2 inhibition. JAK2(V617F) mutational burden, pSTAT3, and PD-L1 expression were highest in primary MPN patient-derived monocytes, megakaryocytes, and platelets. PD-1 inhibition prolonged survival in human MPN xenograft and primary murine MPN models. This effect was dependent on T cells. Mechanistically, PD-L1 surface expression in JAK2(V617F)-mutant cells affected metabolism and cell cycle progression of T cells. In summary, we report that in MPN, constitutive JAK2/STAT3/STAT5 activation, mainly in monocytes, megakaryocytes, and platelets, caused PD-L1-mediated immune escape by reducing T cell activation, metabolic activity, and cell cycle progression. The susceptibility of JAK2(V617F)-mutant MPN to PD-1 targeting paves the way for immunomodulatory approaches relying on PD-1 inhibition.
- Published
- 2017
31. Symptom burden profile in myelofibrosis patients with thrombocytopenia: Lessons and unmet needs
- Author
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Robyn M. Scherber, Claire N. Harrison, Ruben A. Mesa, Stefanie Slot, Junqing Xu, Jean-Jacques Kiladjian, Zefeng Xu, Pablo J. Muxi, Chiara Paoli, Harry C. Schouten, Lydia Roy, Peter A. W. te Boekhorst, Robert Peter Gale, Norman Maldonado, Thomas Lehmann, Karin Bonatz, Maria Luisa Ferrari, Federico Sackmann, Jean Christophe Ianotto, Peihong Zhang, Giovanni Barosi, Alessandro Rambaldi, Bjorn Andreasson, Peter L. Johansson, Xiujuan Sun, Allison H. Scotch, Ana Kerguelen Fuentes, Jean-Yves Cahn, Deepti Radia, Suzan Commandeur, Zhijian Xiao, Jan Samuelsson, Heidi E. Kosiorek, Francisco Cervantes, Yue Zhang, Gabriel Etienne, Heike L. Pahl, Françoise Boyer, Martin Griesshammer, Francesco Passamonti, Konstanze Döhner, Gunnar Birgegård, Sonja Zweegman, Carlos Besses, Alessandro M. Vannucchi, Dana Ranta, Frank Stegelmann, Dolores Hernández-Maraver, Amylou C. Dueck, Holly L. Geyer, Tiziano Barbui, Andreas Reiter, Hematology, Internal Medicine, Internal medicine, and CCA - Cancer Treatment and quality of life
- Subjects
Male ,Quality of life ,medicine.medical_specialty ,Ruxolitinib ,Cancer Research ,Anemia ,Myeloproliferative neoplasm ,Myelofibrosis ,Symptomatology ,Thrombocytopenia ,Hematology ,Oncology ,Severity of Illness Index ,Gastroenterology ,Article ,03 medical and health sciences ,0302 clinical medicine ,Weight loss ,Trombocitopènia ,Surveys and Questionnaires ,Internal medicine ,hemic and lymphatic diseases ,Severity of illness ,medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Leukopenia ,Mielofibrosi ,business.industry ,Middle Aged ,Prognosis ,medicine.disease ,Surgery ,Primary Myelofibrosis ,030220 oncology & carcinogenesis ,Female ,Symptom Assessment ,medicine.symptom ,business ,Needs Assessment ,Follow-Up Studies ,030215 immunology ,medicine.drug - Abstract
Myelofibrosis is a myeloproliferative neoplasm associated with progressive cytopenias and high symptom burden. MF patients with thrombocytopenia have poor prognosis but the presence of thrombocytopenia frequently precludes the use of JAK2 inhibitors. In this study, we assessed quality of life and symptom burden in 418 MF patients with (n = 89) and without (n = 329) thrombocytopenia using prospective data from the MPN-QOL study group database, including the Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF) and Total Symptom Score (MPN10). Thrombocytopenia, defined as platelet count 9/L (moderate 51–100 × 109/L; severe ≤50 × 109/L), was associated with anemia (76% vs. 45%, p < 0.001), leukopenia (29% vs. 11%, p < 0.001), and need for red blood cell transfusion (35% vs. 19%, p = 0.002). Thrombocytopenic patients had more fatigue, early satiety, inactivity, dizziness, sad mood, cough, night sweats, itching, fever, and weight loss; total symptom scores were also higher (33 vs. 24, p < 0.001). Patients with severe thrombocytopenia were more likely to have anemia (86% vs. 67%, p = 0.04), leukopenia (40% vs. 20%, p = 0.04), and transfusion requirements (51% vs. 20%, p = 0.002) but few differences in symptoms when compared to patients with moderate thrombocytopenia. These results suggest that MF patients with thrombocytopenia experience greater symptomatic burden than MF patients without thrombocytopenia and may benefit from additional therapies.
- Published
- 2017
32. The AML1/ETO target gene LAT2 interferes with differentiation of normal hematopoietic precursor cells
- Author
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Aitomi Essig, Michael Lübbert, Sven Schwemmers, Jesus Duque-Afonso, and Heike L. Pahl
- Subjects
Cancer Research ,Myeloid ,Cellular differentiation ,CD34 ,Antigens, CD34 ,Stem cell factor ,Biology ,Lymphocyte Activation ,Monocytes ,Article ,RUNX1 Translocation Partner 1 Protein ,Proto-Oncogene Proteins ,hemic and lymphatic diseases ,medicine ,Humans ,Lymphocytes ,RNA, Small Interfering ,Progenitor cell ,Cells, Cultured ,Adaptor Proteins, Signal Transducing ,Interleukin 3 ,Regulation of gene expression ,Stem Cell Factor ,Granulocyte-Macrophage Colony-Stimulating Factor ,Cell Differentiation ,Hematology ,Hematopoietic Stem Cells ,Molecular biology ,Cell biology ,Haematopoiesis ,medicine.anatomical_structure ,Gene Expression Regulation ,Oncology ,Core Binding Factor Alpha 2 Subunit ,Leukocytes, Mononuclear ,Interleukin-3 ,Granulocytes ,Signal Transduction ,Transcription Factors - Abstract
The adaptor protein linker activator of T-cells 2 (LAT2) is a known AML1/ETO target gene whose function during normal hematopoiesis is unknown. We addressed the role of LAT2 during erythroid and myeloid differentiation of normal human CD34+ hematopoietic cells. LAT2 is expressed at low levels in CD34+ cells and upregulated during cytokine-induced myeloid and erythroid differentiation. Forced LAT2 expression leads to a delay of erythroid and myeloid differentiation keeping CD34+ cells in a more immature state, whereas LAT2 knockdown accelerates differentiation. It is tempting to speculate that by affecting the differentiation capacity of normal hematopoietic progenitors, LAT2 may contribute to the pathogenesis of AML.
- Published
- 2014
33. Differenzialdiagnose myelproliferativer Neoplasien
- Author
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Anna-Verena Frey, Jens Timmer, Martin Werner, Dieter Hauschke, Konrad Aumann, Clemens Kreutz, Heike L. Pahl, Jan P. Marx, and Annette M. May
- Subjects
Pathology ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Essential thrombocythemia ,food and beverages ,medicine.disease ,Pathology and Forensic Medicine ,Polycythemia vera ,medicine.anatomical_structure ,hemic and lymphatic diseases ,Biopsy ,medicine ,Immunohistochemistry ,Bone marrow ,Differential diagnosis ,business ,Myelofibrosis ,Erythroid Precursor Cells - Abstract
Background Besides essential thrombocythemia (ET), polycythemia vera (PV) and primary myelofibrosis (PMF) the myeloproliferative neoplasms (MPN) defined by the World Health Organization (WHO) comprise the entity of unclassifiable MPNs (MPN, U). The exact differential diagnosis of the specific MPN entities can be challenging particularly at early stages of the diseases. So far, pathologists have had to rely only on histomorphological evaluation of bone marrow biopsies in combination with laboratory data because helpful ancillary tests are not yet available. Even molecular tests, such as JAK2 mutation analysis are not helpful particularly in the differential diagnosis of ET and PMF because both entities are associated with the V617F mutation in 50 % of the cases. Recently overexpression of the transcription factor NF-E2 in MPN was described. Materials and methods A collective of samples consisting of 163 bone marrow biopsies including 139 MPN cases was stained immunohistochemically for NF-E2 and analyzed regarding the subcellular localization of NF-E2 in erythroid progenitor cells. The results were compared between the MPN entities as well as the controls and statistical analyses were conducted. Results and discussion This study showed that NF-E2 immunohistochemistry and analysis of the proportion of nuclear positive erythroblasts of all erythroid precursor cells can help to distinguish between ET and PMF even in early stages of the diseases. An MPN, U case showing a proportion of more than 20 % nuclear positive erythroblasts can be classified as a PMF with 92 % accuracy.
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- 2013
34. MPN patients harbor recurrent truncating mutations in transcription factor NF-E2
- Author
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Jan C. Peeken, Thalia S. Seeger, Julius Wehrle, Konstanze Döhner, Heike L. Pahl, Sven Schwemmers, Ruzhica Bogeska, Konrad Aumann, Christine Dierks, Joop H. Jansen, Wei Kamar Wang, Gorica Nikoloski, Jonas S. Jutzi, Frank Stegelmann, Monika Gothwal, Kamar Hamdi, Corina A. Schmid, and Albert Gründer
- Subjects
Transcriptional Activation ,NF-E2 Transcription Factor ,Immunology ,Biology ,Article ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Polycythemia vera ,medicine ,Animals ,Humans ,Immunology and Allergy ,Cell Lineage ,RNA, Messenger ,Transcription factor ,Gene ,Bone Marrow Transplantation ,Cell Proliferation ,030304 developmental biology ,Dominance (genetics) ,Immune Regulation Translational research [NCMLS 2] ,0303 health sciences ,Myeloproliferative Disorders ,Thrombocytosis ,Protein Stability ,Essential thrombocythemia ,food and beverages ,DNA ,Janus Kinase 2 ,Hematopoietic Stem Cells ,medicine.disease ,Molecular biology ,Phenotype ,Clone Cells ,3. Good health ,HEK293 Cells ,NF-E2 Transcription Factor, p45 Subunit ,030220 oncology & carcinogenesis ,Mutation ,Mutant Proteins ,Bone Marrow Neoplasms ,Protein Binding - Abstract
Mutations in the transcription factor NF-E2 in patients with myeloproliferative neoplasms result in a truncated protein that enhances the function of wild-type NF-E2 and causes erythrocytosis and throbocytosis in a mouse model., The molecular etiology of myeloproliferative neoplasms (MPNs) remains incompletely understood, despite recent advances incurred through the discovery of several different mutations in MPN patients. We have recently described overexpression of the transcription factor NF-E2 in MPN patients and shown that elevated NF-E2 levels in vivo cause an MPN phenotype and predispose to leukemic transformation in transgenic mice. We report the presence of acquired insertion and deletion mutations in the NF-E2 gene in MPN patients. These result in truncated NF-E2 proteins that enhance wild-type (WT) NF-E2 function and cause erythrocytosis and thrombocytosis in a murine model. NF-E2 mutant cells acquire a proliferative advantage, witnessed by clonal dominance over WT NF-E2 cells in MPN patients. Our data underscore the role of increased NF-E2 activity in the pathophysiology of MPNs.
- Published
- 2013
35. Transcription factor nuclear factor erythroid-2 mediates expression of the cytokine interleukin 8, a known predictor of inferior outcome in patients with myeloproliferative neoplasms
- Author
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Dietmar Pfeifer, Heike L. Pahl, Thalia S. Seeger, Alla Bulashevska, Julius Wehrle, and Sven Schwemmers
- Subjects
NF-E2 Transcription Factor ,Genetic Vectors ,Antigens, CD34 ,Biology ,Mice ,Myelodysplastic–myeloproliferative diseases ,Predictive Value of Tests ,hemic and lymphatic diseases ,Tumor Cells, Cultured ,medicine ,Animals ,Humans ,Interleukin 8 ,Myelofibrosis ,Transcription factor ,Myeloproliferative neoplasm ,Microarray analysis techniques ,Interleukin-8 ,Lentivirus ,U937 Cells ,Hematology ,medicine.disease ,Myelodysplastic-Myeloproliferative Diseases ,Gene Expression Regulation, Neoplastic ,Treatment Outcome ,NF-E2 Transcription Factor, p45 Subunit ,Gene Targeting ,Immunology ,Cancer research ,Interleukin 19 ,Original Articles and Brief Reports ,Protein Binding - Abstract
The transcription factor nuclear factor erythroid-2 is over-expressed in patients with myeloproliferative neoplasms irrespective of the presence of the JAK2(V617F) mutation. Our transgenic mouse model over-expressing nuclear factor erythroid-2, which recapitulates many features of myeloproliferative neoplasms including transformation to acute myeloid leukemia, clearly implicates this transcription factor in the pathophysiology of myeloproliferative neoplasms. Because the targets mediating nuclear factor erythroid-2 effects are not well characterized, we conducted microarray analysis of CD34(+) cells lentivirally transduced to over-express nuclear factor erythroid-2 or to silence this transcription factor via shRNA, in order to identify novel target genes. Here, we report that the cytokine interleukin 8 is a novel target gene. Nuclear factor erythroid-2 directly binds the interleukin 8 promoter in vivo, and these binding sites are required for promoter activity. Serum levels of interleukin 8 are known to be elevated in both polycythemia vera and primary myelofibrosis patients. Recently, increased interleukin 8 levels have been shown to be predictive of inferior survival in primary myelofibrosis patients in multivariate analysis. Therefore, one of the mechanisms by which nuclear factor erythroid-2 contributes to myeloproliferative neoplasm pathology may be increased interleukin 8 expression.
- Published
- 2013
36. Elevated Nuclear Factor Erythroid-2 Levels Promote Epo-Independent Erythroid Maturation and Recapitulate the Hematopoietic Stem Cell and Common Myeloid Progenitor Expansion Observed in Polycythemia Vera Patients
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Heike L. Pahl and Ruzhica Bogeska
- Subjects
Myeloid ,CD34 ,Gene Expression ,Antigens, CD34 ,Biology ,Myeloproliferative Disorders ,Polycythemia vera ,hemic and lymphatic diseases ,medicine ,Humans ,Erythropoiesis ,Gene Silencing ,Erythropoietin ,Polycythemia Vera ,Cells, Cultured ,Myeloid Progenitor Cells ,Cell Proliferation ,Hematopoietic stem cell ,Cell Biology ,General Medicine ,Flow Cytometry ,Hematopoietic Stem Cells ,Tissue-Specific Progenitor and Stem Cells ,medicine.disease ,Molecular biology ,Endothelial stem cell ,Haematopoiesis ,medicine.anatomical_structure ,NF-E2 Transcription Factor, p45 Subunit ,Cancer research ,Stem cell ,Developmental Biology - Abstract
The molecular etiology of polycythemia vera (PV) remains incompletely understood. Patients harbor increased numbers of hematopoietic stem cells and display Epo-independent erythroid maturation. However, the molecular mechanism underlying Epo hypersensitivity and stem cell expansion is unclear. We have previously shown that the transcription factor nuclear factor erythroid-2 (NF-E2) is overexpressed in the majority of PV patients. Here we demonstrated that elevation of NF-E2 expression in healthy CD34+ cells to levels observed in PV caused Epo-independent erythroid maturation and expansion of hematopoietic stem cell (HSC) and common myeloid progenitor (CMP) cell numbers. Silencing NF-E2 in PV patients reverted both aberrancies, demonstrating for the first time that NF-E2 overexpression is both required and sufficient for Epo independence and HSC/CMP expansion in PV.
- Published
- 2013
37. Haematopoietic stem cell survival and transplantation efficacy is limited by the BH3‐only proteins Bim and Bmf
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Heike L. Pahl, Andreas Villunger, Charlotte M. Niemeyer, Sven Schwemmers, Stephan Geley, D Bertele, Mirjam Kunze, Miriam Erlacher, Denise Tischner, Claudia Woess, Florian J. Bock, and Verena Labi
- Subjects
Cell Survival ,haematopoietic stem cell transplantation ,medicine.medical_treatment ,Transplantation, Heterologous ,Cell ,CD34 ,Biology ,Colony-Forming Units Assay ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Proto-Oncogene Proteins ,Bmf ,medicine ,Animals ,Humans ,Bim ,Progenitor cell ,Cells, Cultured ,Research Articles ,Adaptor Proteins, Signal Transducing ,030304 developmental biology ,Mice, Knockout ,0303 health sciences ,Bcl-2-Like Protein 11 ,Hematopoietic Stem Cell Transplantation ,apoptosis ,Membrane Proteins ,Hematopoietic Stem Cells ,3. Good health ,Cell biology ,Mice, Inbred C57BL ,Transplantation ,Haematopoiesis ,medicine.anatomical_structure ,Cytokine ,030220 oncology & carcinogenesis ,Cord blood ,Molecular Medicine ,Bcl-2 protein family ,Stem cell ,Apoptosis Regulatory Proteins - Abstract
Anti-apoptotic Bcl-2 family members are critical for the regulation of haematopoietic stem and progenitor cell (HSPC) survival. Little is known about the role of their pro-apoptotic antagonists, i.e. 'BH3-only' proteins, in this cell compartment. Based on the analysis of cytokine deprivation-induced changes in mRNA expression levels of Bcl-2 family proteins, we determined the consequences of BH3-only protein depletion on HSPC survival in culture and, for selected candidates, on engraftment in vivo. Thereby, we revealed a critical role for Bim and Bmf as regulators of HSPC dynamics both during early engraftment and long-term reconstitution. HSPCs derived from wild-type donors were readily displaced by Bim- or Bmf-deficient or Bcl-2-overexpressing HSPCs as early as 10 days after engraftment. Moreover, in the absence of Bim, significantly lower numbers of transplanted HSPCs were able to fully engraft radio-depleted recipients. Finally, we provide proof of principle that RNAi-based reduction of BIM or BMF, or overexpression of BCL-2 in human CD34(+) cord blood cells may be an attractive therapeutic option to increase stem cell survival and transplantation efficacy.
- Published
- 2012
38. Associations between gender, disease features and symptom burden in patients with myeloproliferative neoplasms: an analysis by the MPN QOL International Working Group
- Author
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Peihong Zhang, Giovanni Barosi, Zefeng Xu, Alessandro M. Vannucchi, Chiara Paoli, Carlos Besses, Bjorn Andreasson, Peter L. Johansson, Peter A. W. te Boekhorst, Xiujuan Sun, Jan Samuelsson, Gunnar Birgegård, Yue Zhang, Ana Kerguelen Fuentes, Dana Ranta, Ruben A. Mesa, Keith Cannon, Dolores Hernández-Maraver, Andreas Reiter, Robyn M. Scherber, Jean-Yves Cahn, Amylou C. Dueck, Heike L. Pahl, Lydia Roy, Karin Bonatz, Pablo J. Muxi, Zhenya Senyak, Jean-Jacques Kiladjian, Gabriel Etienne, Holly L. Geyer, Stefanie Slot, Robert Peter Gale, Claire N. Harrison, Frank Stegelmann, Federico Sackmann, Francesco Passamonti, Jean Christophe Ianotto, Heidi E. Kosiorek, Martin Griesshammer, Harry C. Schouten, Sonja Zweegman, Norman Maldonado, Maria Luisa Ferrari, Alessandro Rambaldi, Francisco Cervantes, Deepti Radia, Konstanze Döhner, Zhijian Xiao, Tiziano Barbui, Thomas Lehmann, Françoise Boyer, Junqing Xu, Hematology, MUMC+: MA Hematologie (9), RS: GROW - R3 - Innovative Cancer Diagnostics & Therapy, Interne Geneeskunde, Internal medicine, and CCA - Cancer Treatment and quality of life
- Subjects
0301 basic medicine ,Adult ,Male ,medicine.medical_specialty ,Abdominal pain ,Adolescent ,Trombocitèmia ,Disease ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Polycythemia vera ,Sex Factors ,Quality of life ,Internal medicine ,hemic and lymphatic diseases ,Surveys and Questionnaires ,medicine ,80 and over ,Journal Article ,Humans ,Hematologi ,Young adult ,Myelofibrosis ,Càncer ,Aged ,Aged, 80 and over ,Myeloproliferative Disorders ,business.industry ,Essential thrombocythemia ,Hematology ,Articles ,Middle Aged ,medicine.disease ,Prognosis ,Surgery ,030104 developmental biology ,Phenotype ,Qualitat de vida ,030220 oncology & carcinogenesis ,Quality of Life ,Patient-reported outcome ,Female ,medicine.symptom ,business - Abstract
The myeloproliferative neoplasms, including polycythemia vera, essential thrombocythemia and myelofibrosis, are distinguished by their debilitating symptom profiles, life-threatening complications and profound impact on quality of life. The role gender plays in the symptomatology of myeloproliferative neoplasms remains under-investigated. In this study we evaluated how gender relates to patients' characteristics, disease complications and overall symptom expression. A total of 2,006 patients (polycythemia vera=711, essential thrombocythemia=830, myelofibrosis=460, unknown=5) were prospectively evaluated, with patients completing the Myeloproliferative Neoplasm-Symptom Assessment Form and Brief Fatigue Inventory Patient Reported Outcome tools. Information on the individual patients' characteristics, disease complications and laboratory data was collected. Consistent with known literature, most female patients were more likely to have essential thrombocythemia (48.6% versus 33.0%; P
- Published
- 2016
39. Gab2 signaling in chronic myeloid leukemia cells confers resistance to multiple Bcr-Abl inhibitors
- Author
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Martin Werner, Franziska U. Wöhrle, Sebastian Halbach, Sandra Braun, Konrad Aumann, Robert Zeiser, Daniel Schramek, Roger J. Daly, Silke Laßmann, Cornelius F. Waller, S Schwemmers, Josef M. Penninger, Patrick Auberger, Heike L. Pahl, and Tilman Brummer
- Subjects
Male ,Cancer Research ,Dasatinib ,Fusion Proteins, bcr-abl ,Protein Tyrosine Phosphatase, Non-Receptor Type 11 ,Piperazines ,Phosphatidylinositol 3-Kinases ,0302 clinical medicine ,hemic and lymphatic diseases ,Antineoplastic Combined Chemotherapy Protocols ,Tumor Cells, Cultured ,Phosphorylation ,RNA, Small Interfering ,Phosphoinositide-3 Kinase Inhibitors ,0303 health sciences ,TOR Serine-Threonine Kinases ,Imidazoles ,Myeloid leukemia ,Hematology ,Middle Aged ,Prognosis ,3. Good health ,Oncology ,030220 oncology & carcinogenesis ,Benzamides ,Imatinib Mesylate ,Quinolines ,Female ,Tyrosine kinase ,medicine.drug ,Adult ,MAP Kinase Signaling System ,Blotting, Western ,Biology ,03 medical and health sciences ,Leukemia, Myelogenous, Chronic, BCR-ABL Positive ,medicine ,Humans ,Protein Kinase Inhibitors ,Protein kinase B ,PI3K/AKT/mTOR pathway ,Adaptor Proteins, Signal Transducing ,Aged ,030304 developmental biology ,Imatinib ,respiratory tract diseases ,Thiazoles ,Pyrimidines ,Imatinib mesylate ,14-3-3 Proteins ,Nilotinib ,Drug Resistance, Neoplasm ,Cancer research ,Proto-Oncogene Proteins c-akt ,Follow-Up Studies - Abstract
Grb2-associated binder 2 (Gab2) serves as a critical amplifier in the signaling network of Bcr-Abl, the driver of chronic myeloid leukemia (CML). Despite the success of tyrosine kinase inhibitors (TKIs) in CML treatment, TKI resistance, caused by mutations in Bcr-Abl or aberrant activity of its network partners, remains a clinical problem. Using inducible expression and knockdown systems, we analyzed the role of Gab2 in Bcr-Abl signaling in human CML cells, especially with respect to TKI sensitivity. We show for the first time that Gab2 signaling protects CML cells from various Bcr-Abl inhibitors (imatinib, nilotinib, dasatinib and GNF-2), whereas Gab2 knockdown or haploinsufficiency leads to increased TKI sensitivity. We dissected the underlying molecular mechanism using various Gab2 mutants and kinase inhibitors and identified the Shp2/Ras/ERK and the PI3K/AKT/mTOR axes as the two critical signaling pathways. Gab2-mediated TKI resistance was associated with persistent phosphorylation of Gab2 Y452, a PI3K recruitment site, and consistent with this finding, the protective effect of Gab2 was completely abolished by the combination of dasatinib with the dual PI3K/mTOR inhibitor NVP-BEZ235. The identification of Gab2 as a novel modulator of TKI sensitivity in CML suggests that Gab2 could be exploited as a biomarker and therapeutic target in TKI-resistant disease.
- Published
- 2012
40. A novel murine model of myeloproliferative disorders generated by overexpression of the transcription factor NF-E2
- Author
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Monika Gothwal, Alessandro Rambaldi, Brigitte Schlegelberger, Kien Binh Pham, Britta Will, Jonas S. Jutzi, Kai B. Kaufmann, Albert Gründer, Julia M. Wagner, Doris Steinemann, Thomas Günther, Manfred Jung, Konrad Aumann, Thalia S. Seeger, Tobias Hadlich, Julius Wehrle, Roland Schüle, Lucas Ganzenmüller, Sarah Kayser, Ulrich Steidl, Martin Werner, Heike L. Pahl, and Ruzhica Bogeska
- Subjects
medicine.drug_class ,Immunology ,Gene Expression ,Mice, Transgenic ,Biology ,Article ,Mice ,03 medical and health sciences ,Histone H3 ,0302 clinical medicine ,Myeloproliferative Disorders ,NF-E2 Transcription Factor ,hemic and lymphatic diseases ,medicine ,Animals ,Humans ,Immunology and Allergy ,Epigenetics ,Histone H3 acetylation ,Vorinostat ,030304 developmental biology ,Regulation of gene expression ,0303 health sciences ,Blood Cells ,Leukemia ,Histone deacetylase inhibitor ,food and beverages ,Myeloid leukemia ,Cell Differentiation ,Hematopoietic Stem Cells ,Chromatin ,Blood Cell Count ,3. Good health ,Histone Deacetylase Inhibitors ,Disease Models, Animal ,Phenotype ,Gene Expression Regulation ,030220 oncology & carcinogenesis ,Disease Progression ,Cancer research ,medicine.drug - Abstract
Mice expressing a transgene encoding the transcription factor NF-E2 in hematopoietic cells exhibit features of myeloproliferative neoplasms, including thrombocytosis, Epo-independent colony formation, stem and progenitor cell overabundance, leukocytosis, and progression to acute myeloid leukemia., The molecular pathophysiology of myeloproliferative neoplasms (MPNs) remains poorly understood. Based on the observation that the transcription factor NF-E2 is often overexpressed in MPN patients, independent of the presence of other molecular aberrations, we generated mice expressing an NF-E2 transgene in hematopoietic cells. These mice exhibit many features of MPNs, including thrombocytosis, leukocytosis, Epo-independent colony formation, characteristic bone marrow histology, expansion of stem and progenitor compartments, and spontaneous transformation to acute myeloid leukemia. The MPN phenotype is transplantable to secondary recipient mice. NF-E2 can alter histone modifications, and NF-E2 transgenic mice show hypoacetylation of histone H3. Treatment of mice with the histone deacetylase inhibitor (HDAC-I) vorinostat restored physiological levels of histone H3 acetylation, decreased NF-E2 expression, and normalized platelet numbers. Similarly, MPN patients treated with an HDAC-I exhibited a decrease in NF-E2 expression. These data establish a role for NF-E2 in the pathophysiology of MPNs and provide a molecular rationale for investigating epigenetic alterations as novel targets for rationally designed MPN therapies.
- Published
- 2012
41. Symptomatic Profiles of Patients With Polycythemia Vera: Implications of Inadequately Controlled Disease
- Author
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Bjorn Andreasson, Peter L. Johansson, Federico Sackmann, Giovanni Barosi, Zhijian Xiao, Françoise Boyer, Ruben A. Mesa, Suzan Commandeur, Carlos Besses, Tiziano Barbui, Norman Maldonado, Maria Luisa Ferrari, Peter A. W. te Boekhorst, Francisco Cervantes, Jean-Jacques Kiladjian, Yue Zhang, Zhenya Senyak, Harry C. Schouten, Karin Bonatz, Konstanze Döhner, Dana Ranta, Zefeng Xu, Jan Samuelsson, Jean-Yves Cahn, Francesco Passamonti, Deepti Radia, Andreas Reiter, Sonja Zweegman, Xiujuan Sun, Alessandro Rambaldi, Ana Kerguelen Fuentes, Junqing Xu, Thomas Lehmann, Lydia Roy, Gabriel Etienne, Alessandro M. Vannucchi, Heidi E. Kosiorek, Jean Christophe Ianotto, Martin Griesshammer, Peihong Zhang, Robert Peter Gale, Heike L. Pahl, Gunnar Birgegård, Claire N. Harrison, Frank Stegelmann, Robyn M. Scherber, Pablo J. Muxi, Stefanie Slot, Dolores Hernández-Maraver, Amylou C. Dueck, Holly L. Geyer, Hématologie -Immunologie -Cibles thérapeutiques, Université Paris Diderot - Paris 7 (UPD7)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Investigations Cliniques, Hopital Saint-Louis [AP-HP] (AP-HP), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Hematology and Bone Marrow Transplant Unit, Azienda Ospedaliera Papa Giovanni XXIII, Hematology, Ospedali Riuniti, Santé publique, vieillissement, qualité de vie et réadaptation des sujets fragiles - EA 3797 (SPVQVRSF), Université de Reims Champagne-Ardenne (URCA)-SFR CAP Santé (Champagne-Ardenne Picardie Santé), Université de Reims Champagne-Ardenne (URCA)-Université de Reims Champagne-Ardenne (URCA), Service de Médecine Physique Neurologique-Traumatologique [Reims], Université de Reims Champagne-Ardenne (URCA)-Centre Hospitalier Universitaire de Reims (CHU Reims)-Hôpital Sébastopol, Institut de pharmacologie et de biologie structurale (IPBS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut de cancérologie et d'hématologie, Hôpital Morvan [Brest]-Centre Hospitalier Régional Universitaire de Brest (CHRU Brest), Groupe d'Etude de la Thrombose de Bretagne Occidentale (GETBO), Université de Brest (UBO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO)-Université de Brest (UBO), TheREx, Techniques de l'Ingénierie Médicale et de la Complexité - Informatique, Mathématiques et Applications, Grenoble - UMR 5525 (TIMC-IMAG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Réactions et Génie des Procédés (LRGP), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Department of Haematology, Division of Medicine, Institution for Medical Sciences, University Hospital, Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes (LBMCE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institute of medicinal plant development, Chinese Academy of Medical Sciences, State Key Laboratory of Rare Resource Utilization, Changchun Institute of Applied Chemistry, Internal medicine, CCA - Evaluation of Cancer Care, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Université de Brest (UBO)-Institut Brestois Santé Agro Matière (IBSAM), and VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)
- Subjects
Male ,Cancer Research ,Conference Paper ,very elderly ,[SDV]Life Sciences [q-bio] ,thrombocytopenia ,thrombocytosis ,Disease ,Severity of Illness Index ,bone pain ,0302 clinical medicine ,Polycythemia vera ,Phlebotomy ,80 and over ,Hydroxyurea ,genetics ,Prospective Studies ,Prospective cohort study ,abdominal discomfort ,Polycythemia Vera ,antineoplastic agent ,Fatigue ,Aged, 80 and over ,Palpation ,Symptomatic Profiles ,Middle Aged ,Prognosis ,anemia ,3. Good health ,Oncology ,leukocytosis ,priority journal ,validation study ,030220 oncology & carcinogenesis ,Female ,prospective study ,Adult ,medicine.medical_specialty ,Fever ,Anemia ,Pain ,complication ,Antineoplastic Agents ,Sweating ,03 medical and health sciences ,hemoglobin ,hydroxyurea ,Janus kinase, abdominal discomfort ,adult ,controlled study ,disease duration ,fatigue ,fever ,hemoglobin blood level ,human ,leukopenia ,major clinical study ,middle aged ,night sweat ,palpable splenomegaly ,phlebotomy ,polycythemia vera ,pruritus ,splenomegaly ,symptom assessment ,weight reduction ,aged ,antagonists and inhibitors ,female ,male ,pain ,palpation ,prognosis ,severity of illness index ,sweating ,very elderly, Adult ,Aged ,Humans ,Janus Kinases ,Pruritus ,Splenomegaly ,Weight Loss ,Internal medicine ,Severity of illness ,medicine ,Myeloproliferative neoplasm ,Thrombocytosis ,business.industry ,medicine.disease ,Surgery ,business ,Janus kinase ,[SDV.MHEP]Life Sciences [q-bio]/Human health and pathology ,030215 immunology - Abstract
Purpose Polycythemia vera (PV) is a myeloproliferative neoplasm (MPN) associated with disabling symptoms and a heightened risk of life-threatening complications. Recent studies have demonstrated the effectiveness of JAK inhibitor therapy in patients with PV patients who have a history of prior hydroxyurea (HU) use (including resistance or intolerance), phlebotomy requirements, and palpable splenomegaly. We aimed to determine how these features contribute alone and in aggregate to the PV symptom burden. Patients and Methods Through prospective evaluation of 1,334 patients with PV who had characterized symptom burden, we assessed patient demographics, laboratory data, and the presence of splenomegaly by disease feature (ie, known HU use, known phlebotomy requirements, splenomegaly). Results The presence of each feature in itself is associated with a moderately high symptom burden (MPN symptom assessment form [SAF] total symptom score [TSS] range, 27.7 to 29.2) that persists independent of PV risk category. In addition, symptoms incrementally increase in severity with the addition of other features. Patients with PV who had all three features (PV-HUPS) faced the highest total score (MPN-SAF TSS, 32.5) but had similar individual symptom scores to patients with known HU use (PV-HU), known phlebotomy (PV-P), and splenomegaly (PV-S). Conclusion The results of this study suggest that patients with PV who have any one of the features in question (known HU use, known phlebotomy, or splenomegaly) have significant PV-associated symptoms. Furthermore, it demonstrates that many PV symptoms remain severe independent of the number of features present.
- Published
- 2015
42. NFE2 regulates transcription of multiple enzymes in the heme biosynthesis pathway
- Author
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Julius Wehrle, Lara Rheinemann, Thalia S. Seeger, and Heike L. Pahl
- Subjects
chemistry.chemical_classification ,NF-E2 Transcription Factor ,Heme ,Hematology ,Gene Expression Regulation, Enzymologic ,Biosynthetic Pathways ,Cell Line ,NFE2 ,chemistry.chemical_compound ,Enzyme ,Biochemistry ,chemistry ,Transcription (biology) ,hemic and lymphatic diseases ,Humans ,NRF1 ,Online Only Articles ,Transcription factor ,Gene - Abstract
During erythroid differentiation, co-operative activities of erythroid transcription factors co-ordinate transcript levels of genes required for correct maturation.[1][1] These genes include the eight heme biosynthetic enzymes that are sequentially up-regulated to ensure augmented heme synthesis
- Published
- 2014
43. Of mice and men: Human RNA polymerase III promoter U6 is more efficient than its murine homologue for shRNA expression from a lentiviral vector in both human and murine progenitor cells
- Author
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Manuel Mutschler, Roland Roelz, Ingo H. Pilz, and Heike L. Pahl
- Subjects
Cancer Research ,Genetic Vectors ,Biology ,Cell Line ,Small hairpin RNA ,Mice ,Transduction, Genetic ,RNA interference ,Transcription (biology) ,RNA, Small Nuclear ,Sequence Homology, Nucleic Acid ,Gene expression ,Genetics ,Animals ,Humans ,Gene silencing ,Promoter Regions, Genetic ,Molecular Biology ,Transcription factor ,Erythroid Precursor Cells ,Gene knockdown ,Expression vector ,Lentivirus ,RNA Polymerase III ,Cell Biology ,Hematology ,Janus Kinase 2 ,Molecular biology ,RNA Interference - Abstract
Objective RNA interference mediated by transcription of short hairpin RNAs (shRNAs) from lentiviral expression vectors has emerged as an efficient method to effectively and specifically silence gene expression in a vast variety of mammalian cells. shRNA expression is routinely driven by a RNA polymerase III promoter, most often by the U6 promoter. Here we demonstrate that U6 promoter activity—and consequently gene silencing success—differs significantly among species. Materials and Methods We have modified pLeGO-G, an HIV-based third-generation lentivector, to express a 19nt shRNA sequence against the human transcription factor nuclear factor erythroid 2 or against its murine homologue, as well as an shRNA against murine JAK2, from either the human or the murine U6 promoter. Gene silencing efficiency was analyzed in a human erythroleukemic cell line, in primary human CD34 + cells, as well as in a murine erythroleukemic cell line and in primary murine bone marrow. Results ShRNA expression from the human U6 promoter resulted in a fourfold increase in knockdown efficiency compared to expression from the murine U6 promoter in both human and murine cells. Conclusions The U6 promoter constitutes an important determinant for efficient gene silencing by shRNAs.
- Published
- 2010
44. Krüppel-like factor 15 regulates BMPER in endothelial cells
- Author
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Franziska Volkmar, Thomas Helbing, Heike L. Pahl, Christoph Bode, Jennifer Heinke, Cam Patterson, Ulrich Goebel, Martin Moser, and Philipp Diehl
- Subjects
animal structures ,Sp1 Transcription Factor ,Physiology ,Kruppel-Like Transcription Factors ,KLF15 ,Biology ,Bone morphogenetic protein ,Downregulation and upregulation ,Physiology (medical) ,Animals ,Humans ,Promoter Regions, Genetic ,Cells, Cultured ,Sp1 transcription factor ,Gene knockdown ,Endothelin-1 ,Activator (genetics) ,Endothelial Cells ,Nuclear Proteins ,Original Articles ,Receptor, Endothelin B ,Endothelin 1 ,Molecular biology ,Endothelial stem cell ,embryonic structures ,Cattle ,Carrier Proteins ,Cardiology and Cardiovascular Medicine - Abstract
Aims Bone morphogenetic proteins (BMPs) are involved in embryonic and adult blood vessel formation in health and disease. Previous studies have shown that BMP endothelial cell precursor-derived regulator (BMPER) plays an important role in endothelial cell function and blood vessel formation. BMPER is a key regulator of BMP4 activity and a prerequisite for BMP pathway activation by BMP4 in endothelial cells. Here, we characterize the BMPER promoter and elucidate mechanisms of BMPER regulation. Methods and results To investigate transcriptional mechanisms of BMPER expression, the murine BMPER promoter was cloned and characterized. A series of 5′ deletions of the BMPER promoter revealed that the proximal promoter contains activating cis -elements. By overexpression or siRNA-based knockdown, we demonstrate that BMPER expression is activated by Kruppel-like factor (KLF) 15. As determined by gelshift analyses, KLF15 binds directly to a predicted KLF-binding element at −284 bp within the BMPER promoter. Co-expression experiments show that Sp1 acts as an antagonist for KLF15-induced promoter activation. Endothelin-1 was identified as a potent inhibitor of KLF15 and BMPER expression in endothelial cells, suggesting that KLF15 is a transducer of endothelin-1 activity on BMPER expression. The selective ETB endothelin receptor antagonist BQ788 abolished the downregulation of BMPER expression by endothelin-1. Conclusion Mechanistically, we found that KLF15 is a strong and direct activator of the BMPER expression. BMPER is downregulated by endothelin-1 in a dose-dependent fashion and in parallel to KLF15. As KLF15 deficiency is accompanied by a vascular phenotype and BMPER is necessary for proper blood vessel formation, we suggest a chain of events in which the effects of endothelin-1 on BMPER are mediated by KLF15.
- Published
- 2009
45. NF-E2 overexpression delays erythroid maturation and increases erythrocyte production
- Author
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Ingo H. Pilz, Heike L. Pahl, Britta Will, Roland Roelz, Anna Rita Migliaccio, Angela S. Magin, Daniel H. Schanne, Manuel Mutschler, and Martina Buerge
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medicine.medical_specialty ,Erythrocytes ,Cell ,Antigens, CD34 ,Polycythemia ,Biology ,Article ,Blood cell ,Polycythemia vera ,NF-E2 Transcription Factor ,hemic and lymphatic diseases ,Internal medicine ,medicine ,Humans ,Erythropoiesis ,Polycythemia Vera ,Transcription factor ,Erythroid Precursor Cells ,Hematology ,medicine.disease ,Cell biology ,medicine.anatomical_structure ,Endocrinology ,Erythropoietin ,Stem cell ,medicine.drug - Abstract
The transcription factor Nuclear Factor-Erythroid 2 (NF-E2) is overexpressed in the vast majority of patients with polycythaemia vera (PV). In murine models, NF-E2 overexpression increases proliferation and promotes cellular viability in the absence of erythropoietin (EPO). EPO-independent growth is a hallmark of PV. We therefore hypothesized that NF-E2 overexpression contributes to erythrocytosis, the pathognomonic feature of PV. Consequently, we investigated the effect of NF-E2 overexpression in healthy CD34+ cells. NF-E2 overexpression led to a delay in erythroid maturation, manifested by a belated appearance of glycophorin A-positive erythroid precursors. Maturation delay was similarly observed in primary PV patient erythroid cultures compared to healthy controls. Protracted maturation led to a significant increase in the accumulated number of erythroid cells both in PV cultures and in CD34+ cells overexpressing NF-E2. Similarly, NF-E2 overexpression altered erythroid colony formation, leading to an increase in erythroid burst-forming unit formation. These data indicate that NF-E2 overexpression delays the early phase of erythroid maturation, resulting in an expansion of erythroid progenitors, thereby increasing the number of erythrocytes derived from one CD34+ cell. These data propose a role for NF-E2 in mediating the erythrocytosis of PV.
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- 2009
46. Clinical and hematological presentation of children and adolescents with polycythemia vera
- Author
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Mary Frances McMullin, Heike L. Pahl, Holger Cario, Department of Pediatrics and Adolescent Medicine, Universitätsklinikum Ulm - University Hospital of Ulm, Department of Haematology, Queen's University [Belfast] (QUB), Department of Anaesthesiology, and University Hospital of Freiburg
- Subjects
medicine.medical_specialty ,Pediatrics ,Adolescent ,Polycythemia ,Budd-Chiari Syndrome ,Article ,Hydroxycarbamide ,03 medical and health sciences ,0302 clinical medicine ,Polycythemia vera ,medicine ,Humans ,Erythropoiesis ,Leukocytosis ,Child ,Budd–Chiari syndrome ,Gangrene ,Hematologic Tests ,business.industry ,Hematology ,General Medicine ,Middle Aged ,Phlebotomy ,medicine.disease ,Childhood ,Erythrocytosis ,Adolescence ,3. Good health ,Surgery ,Transplantation ,Regimen ,Hematologic Neoplasms ,030220 oncology & carcinogenesis ,medicine.symptom ,business ,030215 immunology ,medicine.drug - Abstract
International audience; Polycythemia vera (PV) in children and adolescents is very rare. Data on clinical and laboratory evaluations as well as on treatment modalities are sparse. Here, we report the long-term clinical course of a PV patient first diagnosed more than 40 years ago at age 12. In addition, after a systematic review of the scientific medical literature, clinical and hematological data of 35 patients (19 female and 17 male) from 25 previous reports are summarized. Three patients developed PV following antecedent hematological malignancies. Budd–Chiari syndrome was diagnosed in seven patients indicating a particular risk of young patients of developing this disorder. One patient presented with ischemic stroke, one patient with gangrene, and three patients with severe hemorrhage. Three patients died from disease-related complications. Hematocrit levels and platelet counts were not correlated with disease severity. Leukocytosis >15 × 10/L was present in 9/35 patients and associated with a thromboembolic or hemorrhagic complication in seven patients. The few available data on molecular genetics and endogenous erythroid colony growth indicate changes comparable to those detectable in adult patients. Treatment varied enormously. It included aspirin, phlebotomy, hydroxycarbamide, busulfan, melphalan, pyrimethamine, and interferon-alpha. Two patients successfully underwent stem cell transplantation. Currently, it is impossible to treat an individual pediatric PV patient with an evidence-based regimen.
- Published
- 2009
47. JAK2 haplotype is a major risk factor for the development of myeloproliferative neoplasms
- Author
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Y. Lynn Wang, Katerina Zoi, Andreas Reiter, Holger Cario, Nicholas C.P. Cross, Francis H. Grand, Andrew Chase, Heike L. Pahl, Richard T. Silver, David Oscier, Andrew Collins, and Amy V. Jones
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Male ,Heterozygote ,Myeloid ,Genotype ,Polymorphism, Single Nucleotide ,Article ,Polycythemia vera ,Germline mutation ,hemic and lymphatic diseases ,Genetics ,medicine ,Humans ,Genetic Predisposition to Disease ,Allele ,Myelofibrosis ,Polycythemia Vera ,Janus kinase 2 ,Models, Genetic ,biology ,Essential thrombocythemia ,Homozygote ,Haplotype ,Janus Kinase 2 ,medicine.disease ,Thrombocytopenia ,Pedigree ,medicine.anatomical_structure ,Amino Acid Substitution ,Haplotypes ,Hematologic Neoplasms ,Immunology ,biology.protein ,Female - Abstract
Chronic myeloproliferative neoplasms (MPNs) are a group of related conditions characterized by the overproduction of cells from one or more myeloid lineages. More than 95% of cases of polycythemia vera, and roughly half of essential thrombocythemia and primary myelofibrosis acquire a unique somatic 1849G>T JAK2 mutation (encoding V617F) that is believed to be a critical driver of excess proliferation. We report here that JAK2(V617F)-associated disease is strongly associated with a specific constitutional JAK2 haplotype, designated 46/1, in all three disease entities compared to healthy controls (polycythemia vera, n = 192, P = 2.9 x 10(-16); essential thrombocythemia, n = 78, P = 8.2 x 10(-9) and myelofibrosis, n = 41, P = 8.0 x 10(-5)). Furthermore, JAK2(V617F) specifically arises on the 46/1 allele in most cases. The 46/1 JAK2 haplotype thus predisposes to the development of JAK2(V617F)-associated MPNs (OR = 3.7; 95% CI = 3.1-4.3) and provides a model whereby a constitutional genetic factor is associated with an increased risk of acquiring a specific somatic mutation.
- Published
- 2009
48. Clinical and molecular characterisation of a prospectively collected cohort of children and adolescents with polycythemia vera
- Author
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Dagmar Pospisilova, Jan M. Herter, Mary Frances McMullin, Milen Minkov, Charlotte M. Niemeyer, Klaus-Michael Debatin, Vladimir Komrska, Holger Cario, Klaus Schwarz, Harald Reinhard, and Heike L. Pahl
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Male ,Isoantigens ,Pediatrics ,medicine.medical_specialty ,Adolescent ,Receptors, Cell Surface ,GPI-Linked Proteins ,Polymerase Chain Reaction ,Article ,Cohort Studies ,Polycythemia vera ,hemic and lymphatic diseases ,Internal medicine ,medicine ,Humans ,Prospective Studies ,RNA, Messenger ,Child ,Prospective cohort study ,Polycythemia Vera ,Membrane Glycoproteins ,Hematology ,business.industry ,Exons ,Janus Kinase 2 ,medicine.disease ,Erythropoietin receptor ,Erythropoietin ,Mutation ,Cohort ,Immunology ,Budd–Chiari syndrome ,Female ,business ,Cohort study ,medicine.drug - Abstract
Erythrocytoses constitute a group of extremely rare diseases in paediatric and juvenile patients. Primary erythrocytoses comprise both congenital erythrocytoses caused, for example, by erythropoietin (Epo)-receptor gene (EPOR) mutations and the acquired myeloproliferative disorder polycythemia vera (PV). PV patients present with a median age of 60 years; only about 1 in 1000 patients presenting with PV is younger than 20 years. Therefore, published data on clinical and laboratory characteristics and on treatment modalities of paediatric PV patients are sparse. Within the framework of a collaborative registry, we collected clinical, haematological and treatment data of children and adolescents with PV. In addition, we assessed the formation of endogenous erythroid colonies (EEC), the granulocyte CD177 (PRV-1) mRNA expression and the presence of an acquired JAK2 mutation in these patients.
- Published
- 2008
49. Carbon Monoxide Inhalation Reduces Pulmonary Inflammatory Response during Cardiopulmonary Bypass in Pigs
- Author
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Matthias Siepe, Heike L. Pahl, Torsten Doenst, Anne Mecklenburg, Phillip Stein, Klaus Geiger, Rene Schmidt, Christian I. Schwer, Christian Schlensak, Martin Roesslein, Ulrich Goebel, Torsten Loop, University of Zurich, and Loop, T
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Antimetabolites ,Swine ,10216 Institute of Anesthesiology ,medicine.medical_treatment ,Interleukin-1beta ,Apoptosis ,Enzyme-Linked Immunosorbent Assay ,610 Medicine & health ,Inflammation ,Lung injury ,law.invention ,law ,medicine ,Cardiopulmonary bypass ,Animals ,Lung ,Carbon Monoxide ,Cardiopulmonary Bypass ,Inhalation ,Caspase 3 ,Tumor Necrosis Factor-alpha ,business.industry ,Blotting, Northern ,Interleukin-10 ,Oxygen ,Interleukin 10 ,surgical procedures, operative ,Anesthesiology and Pain Medicine ,Cytokine ,Carboxyhemoglobin ,Anesthesia ,Models, Animal ,Breathing ,Cytokines ,Tumor necrosis factor alpha ,2703 Anesthesiology and Pain Medicine ,Blood Gas Analysis ,medicine.symptom ,business ,circulatory and respiratory physiology - Abstract
Background Cardiopulmonary bypass (CPB) is associated with pulmonary inflammation and dysfunction. This may lead to acute lung injury and acute respiratory distress syndrome with increased morbidity and mortality. The authors hypothesized that inhaled carbon monoxide before initiation of CPB would reduce inflammatory response in the lungs. Methods In a porcine model, a beating-heart CPB was used. The animals were either randomized to a control group, to standard CPB, or to CPB plus carbon monoxide. In the latter group, lungs were ventilated with 250 ppm inhaled carbon monoxide in addition to standard ventilation before CPB. Lung tissue samples were obtained at various time points, and pulmonary cytokine levels were determined. Results Hemodynamic parameters were largely unaffected by CPB or carbon monoxide inhalation. There were no significant differences in cytokine expression in mononuclear cells between the groups throughout the experimental time course. Compared with standard CPB animals, carbon monoxide significantly suppresses tumor necrosis factor-alpha and interleukin-1beta levels (P < 0.05) and induced the antiinflammatory cytokine interleukin 10 (P < 0.001). Carbon monoxide inhalation modulates effector caspase activity in lung tissue during CPB. Conclusions The results demonstrate that inhaled carbon monoxide significantly reduces CPB-induced inflammation via suppression of tumor necrosis factor alpha, and interleukin-1beta expression and elevation of interleukin 10. Apoptosis induced by CPB was associated with caspase-3 activation and was significantly attenuated by carbon monoxide treatment. Based on the observations of this study, inhaled carbon monoxide could represent a potential new therapeutic modality for counteracting CPB-induced lung injury.
- Published
- 2008
50. Activation of cellular death programs associated with immunosenescence-like phenotype in TPPII knockout mice
- Author
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Ahmed Nil, Marina A. Freudenberg, Simone Gaedicke, Jisen Huai, Heike L. Pahl, Klaus Eichmann, Gabriele Niedermann, Benoît Kanzler, Peter Aichele, Daniele Million, Gabriele Köhler, Peter van Endert, and Elke Firat
- Subjects
Senescence ,Aging ,T-Lymphocytes ,T cell ,Cellular differentiation ,Apoptosis ,Inflammation ,Thymus Gland ,Biology ,Aminopeptidases ,Mice ,Lymphopenia ,medicine ,Animals ,Dipeptidyl-Peptidases and Tripeptidyl-Peptidases ,Cells, Cultured ,Mice, Knockout ,Thymic involution ,Multidisciplinary ,Serine Endopeptidases ,NF-kappa B ,Cell Differentiation ,Immunosenescence ,Biological Sciences ,Fibroblasts ,Phenotype ,medicine.anatomical_structure ,Immunology ,Knockout mouse ,Cancer research ,Tumor Suppressor Protein p53 ,medicine.symptom ,Gene Deletion ,CD8 - Abstract
The giant cytosolic protease tripeptidyl peptidase II (TPPII) has been implicated in the regulation of proliferation and survival of malignant cells, particularly lymphoma cells. To address its functions in normal cellular and systemic physiology we have generated TPPII-deficient mice. TPPII deficiency activates cell type-specific death programs, including proliferative apoptosis in several T lineage subsets and premature cellular senescence in fibroblasts and CD8 + T cells. This coincides with up-regulation of p53 and dysregulation of NF-κB. Prominent degenerative alterations at the organismic level were a decreased lifespan and symptoms characteristic of immunohematopoietic senescence. These symptoms include accelerated thymic involution, lymphopenia, impaired proliferative T cell responses, extramedullary hematopoiesis, and inflammation. Thus, TPPII is important for maintaining normal cellular and systemic physiology, which may be relevant for potential therapeutic applications of TPPII inhibitors.
- Published
- 2008
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