1
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Unexplained Hematocrit Increase after Therapeutic Phlebotomy in a Patient with Marked Erythrocytosis. Case Rep Hematol 2022; 2022:5018388. [PMID: 35990284 PMCID: PMC9388299 DOI: 10.1155/2022/5018388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 08/01/2022] [Indexed: 11/17/2022] Open
Abstract
We report a patient with hereditary erythrocytosis who underwent a therapeutic phlebotomy and had a post-phlebotomy hematocrit that was higher than the pre-phlebotomy hematocrit. We could not discern a reason for this hematocrit increase after phlebotomy. Instead of performing another phlebotomy, we performed an automated red cell depletion via an apheresis instrument. This procedure is essentially a red cell exchange, but 5% albumin is used as the replacement fluid instead of red blood cells. The patient’s hematocrit decreased from 80% to 39% after three consecutive daily red cell depletion procedures. We share our experience to report the unusual finding of a patient’s hematocrit that increased with phlebotomy and to raise awareness of the red cell depletion procedure.
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2
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Screening of Potential Biomarkers in the Peripheral Serum for Steroid-Induced Osteonecrosis of the Femoral Head Based on WGCNA and Machine Learning Algorithms. DISEASE MARKERS 2022; 2022:2639470. [PMID: 35154510 PMCID: PMC8832155 DOI: 10.1155/2022/2639470] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 12/27/2021] [Indexed: 12/24/2022]
Abstract
Background. Steroid-induced osteonecrosis of the femoral head (SONFH) has produced a substantial burden of medical and social experience. However, the current diagnosis is still limited. Thus, this study is aimed at identifying potential biomarkers in the peripheral serum of patients with SONFH. Methods. The expression profile data of SONFH (number: GSE123568) was acquired from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) in SONFH were identified and used for weighted gene coexpression network analysis (WGCNA). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to investigate the biological functions. The protein-protein interaction (PPI) network and machine learning algorithms were employed to screen for potential biomarkers. Gene set enrichment analysis (GSEA), transcription factor (TF) enrichment analysis, and competing endogenous RNA (ceRNA) network were used to determine the biological functions and regulatory mechanisms of the potential biomarkers. Results. A total of 562 DEGs, including 318 upregulated and 244 downregulated genes, were identified between SONFH and control samples, and 94 target genes were screened based on WGCNA. Moreover, biological function analysis suggested that target genes were mainly involved in erythrocyte differentiation, homeostasis and development, and myeloid cell homeostasis and development. Furthermore, GYPA, TMCC2, and BPGM were identified as potential biomarkers in the peripheral serum of patients with SONFH based on machine learning algorithms and showed good diagnostic values. GSEA revealed that GYPA, TMCC2, and BPGM were mainly involved in immune-related biological processes (BPs) and signaling pathways. Finally, we found that GYPA might be regulated by hsa-miR-3137 and that BPGM might be regulated by hsa-miR-340-3p. Conclusion. GYPA, TMCC2, and BPGM are potential biomarkers in the peripheral serum of patients with SONFH and might affect SONFH by regulating erythrocytes and immunity.
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3
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Mikaelsdottir E, Thorleifsson G, Stefansdottir L, Halldorsson G, Sigurdsson JK, Lund SH, Tragante V, Melsted P, Rognvaldsson S, Norland K, Helgadottir A, Magnusson MK, Ragnarsson GB, Kristinsson SY, Reykdal S, Vidarsson B, Gudmundsdottir IJ, Olafsson I, Onundarson PT, Sigurdardottir O, Sigurdsson EL, Grondal G, Geirsson AJ, Geirsson G, Gudmundsson J, Holm H, Saevarsdottir S, Jonsdottir I, Thorgeirsson G, Gudbjartsson DF, Thorsteinsdottir U, Rafnar T, Stefansson K. Genetic variants associated with platelet count are predictive of human disease and physiological markers. Commun Biol 2021; 4:1132. [PMID: 34580418 PMCID: PMC8476563 DOI: 10.1038/s42003-021-02642-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 09/07/2021] [Indexed: 12/13/2022] Open
Abstract
Platelets play an important role in hemostasis and other aspects of vascular biology. We conducted a meta-analysis of platelet count GWAS using data on 536,974 Europeans and identified 577 independent associations. To search for mechanisms through which these variants affect platelets, we applied cis-expression quantitative trait locus, DEPICT and IPA analyses and assessed genetic sharing between platelet count and various traits using polygenic risk scoring. We found genetic sharing between platelet count and counts of other blood cells (except red blood cells), in addition to several other quantitative traits, including markers of cardiovascular, liver and kidney functions, height, and weight. Platelet count polygenic risk score was predictive of myeloproliferative neoplasms, rheumatoid arthritis, ankylosing spondylitis, hypertension, and benign prostate hyperplasia. Taken together, these results advance understanding of diverse aspects of platelet biology and how they affect biological processes in health and disease. Evgenia Mikaelsdottir et al. report a study of variants associated with platelet count among European individuals where they identify 577 associations. They also report a genetic overlap between platelet count and human diseases, including myeloproliferative neoplasms, rheumatoid arthritis, and hypertension, as well as a genetic overlap between platelet count and various physiological markers.
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Affiliation(s)
| | | | | | | | | | - Sigrun H Lund
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland
| | | | - Pall Melsted
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland.,School of Engineering and Natural Sciences, University of Iceland, Reykjavik, Iceland
| | | | | | | | - Magnus K Magnusson
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland.,Faculty of Medicine, University of Iceland, 101, Reykjavik, Iceland
| | - Gunnar B Ragnarsson
- Department of Oncology, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | - Sigurdur Y Kristinsson
- Faculty of Medicine, University of Iceland, 101, Reykjavik, Iceland.,Department of Hematology, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | - Sigrun Reykdal
- Department of Hematology, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | - Brynjar Vidarsson
- Department of Hematology, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | | | - Isleifur Olafsson
- Department of Clinical Biochemistry, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | - Pall T Onundarson
- Faculty of Medicine, University of Iceland, 101, Reykjavik, Iceland.,Laboratory Hematology, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | - Olof Sigurdardottir
- Department of Clinical Biochemistry, Akureyri Hospital, 600, Akureyri, Iceland
| | | | - Gerdur Grondal
- Department of Rheumatology, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | - Arni J Geirsson
- Department of Rheumatology, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | - Gudmundur Geirsson
- Department of Urology, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | | | - Hilma Holm
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland
| | - Saedis Saevarsdottir
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland.,Faculty of Medicine, University of Iceland, 101, Reykjavik, Iceland.,Department of Rheumatology, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | - Ingileif Jonsdottir
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland.,Faculty of Medicine, University of Iceland, 101, Reykjavik, Iceland
| | - Gudmundur Thorgeirsson
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland.,Department of Cardiology, Landspitali-University Hospital, 101, Reykjavik, Iceland
| | - Daniel F Gudbjartsson
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland.,School of Engineering and Natural Sciences, University of Iceland, Reykjavik, Iceland
| | - Unnur Thorsteinsdottir
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland.,Faculty of Medicine, University of Iceland, 101, Reykjavik, Iceland
| | - Thorunn Rafnar
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland
| | - Kari Stefansson
- deCODE Genetics/Amgen, Sturlugata 8, 101, Reykjavik, Iceland. .,Faculty of Medicine, University of Iceland, 101, Reykjavik, Iceland.
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4
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Han EY, Catherwood M, McMullin MF. Hereditary thrombocytosis: the genetic landscape. Br J Haematol 2021; 194:1098-1105. [PMID: 34341988 DOI: 10.1111/bjh.17741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eun Y Han
- Centre for Medical Education, Queen's University Belfast, Belfast, UK
| | - Mark Catherwood
- Department of Haematology, Belfast City Hospital, Belfast, UK
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5
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Trottier AM, Godley LA. Inherited predisposition to haematopoietic malignancies: overcoming barriers and exploring opportunities. Br J Haematol 2020; 194:663-676. [PMID: 33615436 DOI: 10.1111/bjh.17247] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 11/02/2020] [Indexed: 12/14/2022]
Abstract
Inherited predisposition to haematopoietic malignancies, due to deleterious germline variants in a variety of genes, is an important clinical entity with implications for the health and management of patients and their family members. Unfortunately, there remain several common misconceptions in this field that can result in patients going unrecognised and/or having incomplete or improper testing including: the impression that inherited haematological malignancy syndromes are rare, that myeloid and lymphoid malignancy predisposition syndromes are mutually exclusive, and that solid tumour predisposition syndromes are unique and distinct from haematopoietic malignancy predisposition syndromes. In the present review, we challenge these ideas with our insights into germline genetic testing for these conditions with the hope that increased awareness and knowledge will overcome barriers and lead to improved diagnosis and management.
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Affiliation(s)
- Amy M Trottier
- Division of Hematology, Department of Medicine, QEII Health Sciences Centre/Dalhousie University, Halifax, NS, Canada
| | - Lucy A Godley
- Section of Hematology/Oncology, Departments of Medicine and Human Genetics, The University of Chicago, Chicago, IL, USA
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6
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Xu G, van Bruggen R, Gualtieri CO, Moradin N, Fois A, Vallerand D, De Sa Tavares Russo M, Bassenden A, Lu W, Tam M, Lesage S, Girouard H, Avizonis DZ, Deblois G, Prchal JT, Stevenson M, Berghuis A, Muir T, Rabinowitz J, Vidal SM, Fodil N, Gros P. Bisphosphoglycerate Mutase Deficiency Protects against Cerebral Malaria and Severe Malaria-Induced Anemia. Cell Rep 2020; 32:108170. [PMID: 32966787 DOI: 10.1016/j.celrep.2020.108170] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 07/07/2020] [Accepted: 08/27/2020] [Indexed: 11/30/2022] Open
Abstract
The replication cycle and pathogenesis of the Plasmodium malarial parasite involves rapid expansion in red blood cells (RBCs), and variants of certain RBC-specific proteins protect against malaria in humans. In RBCs, bisphosphoglycerate mutase (BPGM) acts as a key allosteric regulator of hemoglobin/oxyhemoglobin. We demonstrate here that a loss-of-function mutation in the murine Bpgm (BpgmL166P) gene confers protection against both Plasmodium-induced cerebral malaria and blood-stage malaria. The malaria protection seen in BpgmL166P mutant mice is associated with reduced blood parasitemia levels, milder clinical symptoms, and increased survival. The protective effect of BpgmL166P involves a dual mechanism that enhances the host's stress erythroid response to Plasmodium-driven RBC loss and simultaneously alters the intracellular milieu of the RBCs, including increased oxyhemoglobin and reduced energy metabolism, reducing Plasmodium maturation, and replication. Overall, our study highlights the importance of BPGM as a regulator of hemoglobin/oxyhemoglobin in malaria pathogenesis and suggests a new potential malaria therapeutic target.
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Affiliation(s)
- Guoyue Xu
- Department of Human Genetics, McGill University, Montreal, QC H3A 0C7, Canada; McGill University Research Centre on Complex Traits, McGill University, Montreal, QC H3G 0B1, Canada
| | - Rebekah van Bruggen
- McGill University Research Centre on Complex Traits, McGill University, Montreal, QC H3G 0B1, Canada; Department of Biochemistry, McGill University, Montreal, QC H3A 1A3, Canada
| | - Christian O Gualtieri
- McGill University Research Centre on Complex Traits, McGill University, Montreal, QC H3G 0B1, Canada; Department of Biochemistry, McGill University, Montreal, QC H3A 1A3, Canada
| | - Neda Moradin
- McGill University Research Centre on Complex Traits, McGill University, Montreal, QC H3G 0B1, Canada
| | - Adrien Fois
- Immunology-Oncology Unit, Maisonneuve-Rosemont Hospital Research Center, Montréal, QC H1T 2M4, Canada; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Diane Vallerand
- Université de Montréal, Département de Pharmacologie et Physiologie, Pav Roger-Gaudry, 2900 Édouard-Montpetit, Montréal, QC H3T 1J4, Canada
| | | | - Angelia Bassenden
- Department of Biochemistry, McGill University, Montreal, QC H3A 1A3, Canada
| | - Wenyun Lu
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Mifong Tam
- Department of Microbiology and Immunology, McGill University, Montréal, QC H3A 2B4, Canada
| | - Sylvie Lesage
- Immunology-Oncology Unit, Maisonneuve-Rosemont Hospital Research Center, Montréal, QC H1T 2M4, Canada; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Hélène Girouard
- Université de Montréal, Département de Pharmacologie et Physiologie, Pav Roger-Gaudry, 2900 Édouard-Montpetit, Montréal, QC H3T 1J4, Canada
| | - Daina Zofija Avizonis
- Rosalind and Morris Goodman Cancer Research Centre, 1160 Pin Avenue West, Montréal, QC H3A 1A3, Canada
| | - Geneviève Deblois
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC H3T 1J4, Canada; Faculté de Pharmacie, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | - Josef T Prchal
- Division of Hematology, School of Medicine, University of Utah, Salt Lake City, UT 84132, USA
| | - Mary Stevenson
- Department of Microbiology and Immunology, McGill University, Montréal, QC H3A 2B4, Canada
| | - Albert Berghuis
- Department of Biochemistry, McGill University, Montreal, QC H3A 1A3, Canada
| | - Tom Muir
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA; Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Joshua Rabinowitz
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA; Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Silvia M Vidal
- Department of Human Genetics, McGill University, Montreal, QC H3A 0C7, Canada; McGill University Research Centre on Complex Traits, McGill University, Montreal, QC H3G 0B1, Canada; Department of Microbiology and Immunology, McGill University, Montréal, QC H3A 2B4, Canada
| | - Nassima Fodil
- McGill University Research Centre on Complex Traits, McGill University, Montreal, QC H3G 0B1, Canada; Centre CERMO-FC Pavillon des Sciences Biologiques, 141 Avenue du Président Kennedy, Montréal, QC H2X 3Y7, Canada.
| | - Philippe Gros
- Department of Human Genetics, McGill University, Montreal, QC H3A 0C7, Canada; McGill University Research Centre on Complex Traits, McGill University, Montreal, QC H3G 0B1, Canada; Department of Biochemistry, McGill University, Montreal, QC H3A 1A3, Canada.
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7
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Lappin TR, Lee FS. Update on mutations in the HIF: EPO pathway and their role in erythrocytosis. Blood Rev 2019; 37:100590. [PMID: 31350093 DOI: 10.1016/j.blre.2019.100590] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 07/02/2019] [Accepted: 07/15/2019] [Indexed: 12/20/2022]
Abstract
Identification of the underlying defects in congenital erythrocytosis has provided mechanistic insights into the regulation of erythropoiesis and oxygen homeostasis. The Hypoxia Inducible Factor (HIF) pathway plays a key role in this regard. In this pathway, an enzyme, Prolyl Hydroxylase Domain protein 2 (PHD2), constitutively prolyl hydroxylates HIF-2α, thereby targeting HIF-2α for degradation by the von Hippel Lindau (VHL) tumor suppressor protein. Under hypoxia, this modification is attenuated, resulting in the stabilization of HIF-2α and transcriptional activation of the erythropoietin (EPO) gene. Circulating EPO then binds to the EPO receptor (EPOR) on red cell progenitors in the bone marrow, leading to expansion of red cell mass. Loss of function mutations in PHD2 and VHL, as well as gain of function mutations in HIF-2α and EPOR, are well established causes of erythrocytosis. Here, we highlight recent developments that show that the study of this condition is still evolving. Specifically, novel mutations have been identified that either change amino acids in the zinc finger domain of PHD2 or alter splicing of the VHL gene. In addition, continued study of HIF-2α mutations has revealed a distinctive genotype-phenotype correlation. Finally, novel mutations have recently been identified in the EPO gene itself. Thus, the cascade of genes that at a molecular level leads to EPO action, namely PHD2 - > HIF2A - > VHL - > EPO - > EPOR, are all mutational targets in congenital erythrocytosis.
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Affiliation(s)
- Terence R Lappin
- Centre for Cancer Research and Cell Biology, Queen's University, Belfast, UK.
| | - Frank S Lee
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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8
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Abstract
Platelets are anuclear blood cells required for haemostasis and are implicated in other processes including inflammation and metastasis. Platelets are produced by megakaryocytes, specialized cells that are themselves generated by a process of controlled differentiation and maturation of bone-marrow stem and progenitor cells. This process of megakaryopoiesis involves the coordinated interplay of transcription factor-controlled cellular programming with extra-cellular cues produced locally in supporting niches or as circulating factors. This review focuses on these external cues, the cytokines and chemokines, that drive production of megakaryocytes and support the terminal process of platelet release. Emphasis is given to thrombopoietin (Tpo), the major cytokine regulator of steady-state megakaryopoiesis, and its specific cell surface receptor, the Mpl protein, including normal and pathological roles as well as clinical application. The potential for alternative or supplementary regulatory mechanisms for platelet production, particularly in times of acute need, or in states of infection or inflammation are also discussed.
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Affiliation(s)
- Kira Behrens
- a The Walter and Eliza Hall Institute of Medical Research , Parkville , Australia
- b Department of Medical Biology , University of Melbourne , Melbourne , Australia
| | - Warren S Alexander
- a The Walter and Eliza Hall Institute of Medical Research , Parkville , Australia
- b Department of Medical Biology , University of Melbourne , Melbourne , Australia
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9
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Aral B, Courtois M, Ragot S, Bourgeois V, Bottolier-Lemallaz E, Briandet C, Girodon F. Germline JAK2 L611S mutation in a child with thrombocytosis. Haematologica 2018; 103:e372-e373. [PMID: 29567786 DOI: 10.3324/haematol.2018.188995] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Bernard Aral
- Laboratoire de génétique chromosomique et moléculaire, Pôle Biologie, CHU de Dijon, France
| | - Martine Courtois
- Service d'Hématologie Biologique, Pôle Biologie, CHU de Dijon, France
| | - Sylviane Ragot
- Laboratoire de génétique chromosomique et moléculaire, Pôle Biologie, CHU de Dijon, France
| | | | | | - Claire Briandet
- Service d'Immuno-Hématologie Pédiatrique, CHU de Dijon, France
| | - François Girodon
- Service d'Hématologie Biologique, Pôle Biologie, CHU de Dijon, France .,Inserm U1231, Université de Bourgogne, Dijon, France
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10
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Vainchenker W, Leroy E, Gilles L, Marty C, Plo I, Constantinescu SN. JAK inhibitors for the treatment of myeloproliferative neoplasms and other disorders. F1000Res 2018; 7:82. [PMID: 29399328 PMCID: PMC5773931 DOI: 10.12688/f1000research.13167.1] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/11/2018] [Indexed: 01/04/2023] Open
Abstract
JAK inhibitors have been developed following the discovery of the
JAK2V617F in 2005 as the driver mutation of the majority of non-
BCR-ABL1 myeloproliferative neoplasms (MPNs). Subsequently, the search for JAK2 inhibitors continued with the discovery that the other driver mutations (
CALR and
MPL) also exhibited persistent JAK2 activation. Several type I ATP-competitive JAK inhibitors with different specificities were assessed in clinical trials and exhibited minimal hematologic toxicity. Interestingly, these JAK inhibitors display potent anti-inflammatory activity. Thus, JAK inhibitors targeting preferentially JAK1 and JAK3 have been developed to treat inflammation, autoimmune diseases, and graft-versus-host disease. Ten years after the beginning of clinical trials, only two drugs have been approved by the US Food and Drug Administration: one JAK2/JAK1 inhibitor (ruxolitinib) in intermediate-2 and high-risk myelofibrosis and hydroxyurea-resistant or -intolerant polycythemia vera and one JAK1/JAK3 inhibitor (tofacitinib) in methotrexate-resistant rheumatoid arthritis. The non-approved compounds exhibited many off-target effects leading to neurological and gastrointestinal toxicities, as seen in clinical trials for MPNs. Ruxolitinib is a well-tolerated drug with mostly anti-inflammatory properties. Despite a weak effect on the cause of the disease itself in MPNs, it improves the clinical state of patients and increases survival in myelofibrosis. This limited effect is related to the fact that ruxolitinib, like the other type I JAK2 inhibitors, inhibits equally mutated and wild-type JAK2 (JAK2WT) and also the JAK2 oncogenic activation. Thus, other approaches need to be developed and could be based on either (1) the development of new inhibitors specifically targeting
JAK2V617F or (2) the combination of the actual JAK2 inhibitors with other therapies, in particular with molecules targeting pathways downstream of JAK2 activation or the stability of JAK2 molecule. In contrast, the strong anti-inflammatory effects of the JAK inhibitors appear as a very promising therapeutic approach for many inflammatory and auto-immune diseases.
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Affiliation(s)
- William Vainchenker
- INSERM UMR 1170, Gustave Roussy, Villejuif, France.,Université Paris-Saclay, UMR1170, Gustave Roussy, Villejuif, France.,UMR 1170, Gustave Roussy, Villejuif, France
| | - Emilie Leroy
- Signal Transduction & Molecular Hematology Unit, Ludwig Institute for Cancer Research, Brussels, Belgium.,de Duve Institute, Université catholique de Louvain, Brussels, Belgium
| | - Laure Gilles
- Institut National de la Transfusion Sanguine, Paris, France
| | - Caroline Marty
- INSERM UMR 1170, Gustave Roussy, Villejuif, France.,Université Paris-Saclay, UMR1170, Gustave Roussy, Villejuif, France.,UMR 1170, Gustave Roussy, Villejuif, France
| | - Isabelle Plo
- INSERM UMR 1170, Gustave Roussy, Villejuif, France.,Université Paris-Saclay, UMR1170, Gustave Roussy, Villejuif, France.,UMR 1170, Gustave Roussy, Villejuif, France
| | - Stefan N Constantinescu
- Signal Transduction & Molecular Hematology Unit, Ludwig Institute for Cancer Research, Brussels, Belgium.,de Duve Institute, Université catholique de Louvain, Brussels, Belgium
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11
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Diagnosis, risk stratification, and response evaluation in classical myeloproliferative neoplasms. Blood 2016; 129:680-692. [PMID: 28028026 DOI: 10.1182/blood-2016-10-695957] [Citation(s) in RCA: 161] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 12/02/2016] [Indexed: 12/14/2022] Open
Abstract
Philadelphia-negative classical myeloproliferative neoplasms (MPNs) include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). The 2016 revision of the WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues includes new criteria for the diagnosis of these disorders. Somatic mutations in the 3 driver genes, that is, JAK2, CALR, and MPL, represent major diagnostic criteria in combination with hematologic and morphological abnormalities. PV is characterized by erythrocytosis with suppressed endogenous erythropoietin production, bone marrow panmyelosis, and JAK2 mutation. Thrombocytosis, bone marrow megakaryocytic proliferation, and presence of JAK2, CALR, or MPL mutation are the main diagnostic criteria for ET. PMF is characterized by bone marrow megakaryocytic proliferation, reticulin and/or collagen fibrosis, and presence of JAK2, CALR, or MPL mutation. Prefibrotic myelofibrosis represents an early phase of myelofibrosis, and is characterized by granulocytic/megakaryocytic proliferation and lack of reticulin fibrosis in the bone marrow. The genomic landscape of MPNs is more complex than initially thought and involves several mutant genes beyond the 3 drivers. Comutated, myeloid tumor-suppressor genes contribute to phenotypic variability, phenotypic shifts, and progression to more aggressive disorders. Patients with myeloid neoplasms are at variable risk of vascular complications, including arterial or venous thrombosis and bleeding. Current prognostic models are mainly based on clinical and hematologic parameters, but innovative models that include genetic data are being developed for both clinical and trial settings. In perspective, molecular profiling of MPNs might also allow for accurate evaluation and monitoring of response to innovative drugs that target the mutant clone.
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12
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Genomic landscape of megakaryopoiesis and platelet function defects. Blood 2016; 127:1249-59. [PMID: 26787733 DOI: 10.1182/blood-2015-07-607952] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 01/05/2016] [Indexed: 12/17/2022] Open
Abstract
Megakaryopoiesis is a complex, stepwise process that takes place largely in the bone marrow. At the apex of the hierarchy, hematopoietic stem cells undergo a number of lineage commitment decisions that ultimately lead to the production of polyploid megakaryocytes. On average, megakaryocytes release 10(11) platelets per day into the blood that repair vascular injuries and prevent excessive bleeding. This differentiation process is tightly controlled by exogenous and endogenous factors, which have been the topics of intense research in the hematopoietic field. Indeed, a skewing of megakaryocyte commitment and differentiation may entail the onset of myeloproliferative neoplasms and other preleukemic disorders together with acute megakaryoblastic leukemia, whereas quantitative or qualitative defects in platelet production can lead to inherited platelet disorders. The recent advent of next-generation sequencing has prompted mapping of the genomic landscape of these conditions to provide an accurate view of the underlying lesions. The aims of this review are to introduce the physiological pathways of megakaryopoiesis and to present landmark studies on acquired and inherited disorders that target them. These studies have not only introduced a new era in the fields of molecular medicine and targeted therapies but may also provide us with a better understanding of the mechanisms underlying normal megakaryopoiesis and thrombopoiesis that can inform efforts to create alternative sources of megakaryocytes and platelets.
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