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Durand P, Pottier V, Mesguich C, Debordeaux F, Lazaro E, Viallard JF, Rivière E. Utility of indium-111 platelet scintigraphy for understanding the mechanism of thrombocytopenia associated with myelodysplastic syndromes and chronic myelomonocytic leukemia. Exp Hematol Oncol 2023; 12:50. [PMID: 37254182 DOI: 10.1186/s40164-023-00414-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 05/15/2023] [Indexed: 06/01/2023] Open
Abstract
BACKGROUND Thrombocytopenia occurs in 60% of patients with myelodysplastic syndromes (MDS), increasing the risk of life-threatening haemorrhage in this population of mainly old patients with comorbidities. However, data are scare regarding immune thrombocytopenia (ITP) secondary to MDS. AIM We analyzed the utility of indium-111 platelet scintigraphy (IPS) to better characterize the mechanisms of thrombocytopenia in 21 adult patients with MDS. METHODS Adult patients with a definite diagnosis of MDS according to the international criteria who underwent IPS between 2009 and 2018 because of an increased bleeding risk were retrospectively selected. Autologous 111Indium platelet labelling was performed with a technique similar to that described previously using a standardized method. RESULTS Platelet lifespan ≤ 6 days identified patients with peripheral platelet destruction. Taking into account the response to ITP-directed therapies after IPS, the sensitivity, specificity, and positive and negative predictive values of IPS were 100%, 84.6%, 80%, and 100%, respectively. CONCLUSION We show that IPS can be a useful tool to identify the mechanism and guide treatment of a chronic thrombocytopenia increasing the bleeding risk in patients with MDS.
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Affiliation(s)
- Pauline Durand
- Department of Internal Medicine and Infectious Diseases, Haut-Leveque Hospital, University Hospital Centre of Bordeaux, 33600, Pessac, France
| | - Valérie Pottier
- Radiopharmacy Department, University Hospital Centre of Bordeaux, Pessac, France
| | - Charles Mesguich
- Radiopharmacy Department, University Hospital Centre of Bordeaux, Pessac, France
- Nuclear Medicine Department, University Hospital Centre of Bordeaux, Pessac, France
- Faculty of Medicine, Bordeaux University, 33000, Bordeaux, France
| | - Frédéric Debordeaux
- Radiopharmacy Department, University Hospital Centre of Bordeaux, Pessac, France
| | - Estibaliz Lazaro
- Department of Internal Medicine and Infectious Diseases, Haut-Leveque Hospital, University Hospital Centre of Bordeaux, 33600, Pessac, France
- UMR CNRS 5164, ImmunoconcEpT and FHU ACRONIM, Bordeaux University, 33000, Bordeaux, France
- Faculty of Medicine, Bordeaux University, 33000, Bordeaux, France
| | - Jean-François Viallard
- Department of Internal Medicine and Infectious Diseases, Haut-Leveque Hospital, University Hospital Centre of Bordeaux, 33600, Pessac, France
- Faculty of Medicine, Bordeaux University, 33000, Bordeaux, France
- INSERM U1034, Bordeaux University, 33604, Pessac Cedex, France
| | - Etienne Rivière
- Department of Internal Medicine and Infectious Diseases, Haut-Leveque Hospital, University Hospital Centre of Bordeaux, 33600, Pessac, France.
- Faculty of Medicine, Bordeaux University, 33000, Bordeaux, France.
- INSERM U1034, Bordeaux University, 33604, Pessac Cedex, France.
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Yang S, Wang L, Wu Y, Wu A, Huang F, Tang X, Kantawong F, Anuchapreeda S, Qin D, Mei Q, Chen J, Huang X, Zhang C, Wu J. Apoptosis in megakaryocytes: Safeguard and threat for thrombopoiesis. Front Immunol 2023; 13:1025945. [PMID: 36685543 PMCID: PMC9845629 DOI: 10.3389/fimmu.2022.1025945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 12/09/2022] [Indexed: 01/06/2023] Open
Abstract
Platelets, generated from precursor megakaryocytes (MKs), are central mediators of hemostasis and thrombosis. The process of thrombopoiesis is extremely complex, regulated by multiple factors, and related to many cellular events including apoptosis. However, the role of apoptosis in thrombopoiesis has been controversial for many years. Some researchers believe that apoptosis is an ally of thrombopoiesis and platelets production is apoptosis-dependent, while others have suggested that apoptosis is dispensable for thrombopoiesis, and is even inhibited during this process. In this review, we will focus on this conflict, discuss the relationship between megakaryocytopoiesis, thrombopoiesis and apoptosis. In addition, we also consider why such a vast number of studies draw opposite conclusions of the role of apoptosis in thrombopoiesis, and try to figure out the truth behind the mystery. This review provides more comprehensive insights into the relationship between megakaryocytopoiesis, thrombopoiesis, and apoptosis and finds some clues for the possible pathological mechanisms of platelet disorders caused by abnormal apoptosis.
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Affiliation(s)
- Shuo Yang
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Long Wang
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Yuesong Wu
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Anguo Wu
- School of Pharmacy, Southwest Medical University, Luzhou, China
- Institute of Cardiovascular Research, the Key Laboratory of Medical Electrophysiology, Ministry of Education of China, Medical Key Laboratory for Drug Discovery and Druggability Evaluation of Sichuan Province, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Luzhou, China
| | - Feihong Huang
- School of Pharmacy, Southwest Medical University, Luzhou, China
- Institute of Cardiovascular Research, the Key Laboratory of Medical Electrophysiology, Ministry of Education of China, Medical Key Laboratory for Drug Discovery and Druggability Evaluation of Sichuan Province, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Luzhou, China
| | - Xiaoqin Tang
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Fahsai Kantawong
- Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Songyot Anuchapreeda
- Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Dalian Qin
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Qibing Mei
- School of Pharmacy, Southwest Medical University, Luzhou, China
- School of Chinese Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Jianping Chen
- School of Chinese Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Xinwu Huang
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Chunxiang Zhang
- Institute of Cardiovascular Research, the Key Laboratory of Medical Electrophysiology, Ministry of Education of China, Medical Key Laboratory for Drug Discovery and Druggability Evaluation of Sichuan Province, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Luzhou, China
| | - Jianming Wu
- School of Pharmacy, Southwest Medical University, Luzhou, China
- Institute of Cardiovascular Research, the Key Laboratory of Medical Electrophysiology, Ministry of Education of China, Medical Key Laboratory for Drug Discovery and Druggability Evaluation of Sichuan Province, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Luzhou, China
- School of Basic Medical Sciences, Southwest Medical University, Luzhou, China
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3
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Elzaeem DI, Sharkawi EAE, Zaki EM, Ghobrial AG, El-Fatah ASA, El-Hamed WMA. Comparative study of IgG binding to megakaryocytes in immune and myelodysplastic thrombocytopenic patients. Ann Hematol 2021; 100:1701-1709. [PMID: 33982136 DOI: 10.1007/s00277-021-04556-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 05/04/2021] [Indexed: 11/24/2022]
Abstract
Immune thrombocytopenia (ITP) is a disorder in which autoantibodies are responsible for destruction and decreased production of platelets. In the meantime, thrombocytopenia is frequent in patients with myelodysplastic syndromes (MDS) and immune clearance of megakaryocytes could be a reason. The aim of the present study is to evaluate and compare IgG binding to megakaryocytes in bone marrow of ITP and MDS patients to determine megakaryocytes targeting by autoantibodies in vivo as a mechanism of platelet underproduction in these disorders. The study was carried out on 20 ITP (group I) patients, 20 thrombocytopenic patients with (MDS) (group II), and 20 non-ITP patients as a control (group III) who were admitted to Minia University Hospital. Serial histological sections from bone marrow biopsies were stained for IgG. All patients in group I and 50% of group II patients showed bleeding tendency and the difference was significant (p < 0.001). No patient experienced fatigue in group I while 35% of patients in group II complained of easy fatigability, and the difference was significant (p < 0.008). High IgG antibody binding was found in ITP and MDS compared to the control group but no significant difference between ITP and MDS patients (14/20 (70%) vs. 13/20 (65%)) (p value = 0.736). Antibody binding to megakaryocytes in a proportion of MDS patients suggests that immune-mediated mechanism underlies platelet underproduction in those patients.
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Affiliation(s)
- Doaa I Elzaeem
- Clinical Pathology Department, Faculty of Medicine, Minia University, Cornish Al-Nile Road, PO: 61519, Minia, Egypt
| | - Esmat A El Sharkawi
- Clinical Pathology Department, Faculty of Medicine, Minia University, Cornish Al-Nile Road, PO: 61519, Minia, Egypt
| | - Eman M Zaki
- Clinical Pathology Department, Faculty of Medicine, Assiut University, PO: 71515, Assiut, Egypt
| | - Ayman G Ghobrial
- Clinical Pathology Department, Faculty of Medicine, Minia University, Cornish Al-Nile Road, PO: 61519, Minia, Egypt
| | - Aliaa S Abd El-Fatah
- Internal Medicine Department, Faculty of Medicine, Minia University, PO: 61519, Minia, Egypt
| | - Waleed M Abd El-Hamed
- Clinical Pathology Department, Faculty of Medicine, Minia University, Cornish Al-Nile Road, PO: 61519, Minia, Egypt.
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4
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Chen L, Zhou H, Guo B, Guan Z. Clinical efficacy of platelet transfusion therapy in patients with leukemia and analysis of risk factors for ineffective transfusion. Oncol Lett 2020; 19:2554-2561. [PMID: 32194759 PMCID: PMC7039127 DOI: 10.3892/ol.2020.11268] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 12/17/2019] [Indexed: 11/05/2022] Open
Abstract
Clinical efficacy of platelet transfusion therapy in patients with leukemia was investigated to analyze risk factors for ineffective transfusion. A total of 105 cases of patients with leukemia admitted to The First Affiliated Hospital of Bengbu Medical College from August 2016 to November 2018 were selected as research subjects. A total of 49 patients received transfusion of apheresis platelet suspension, and were group A. Fifty-six patients who received mixed multi-person platelet suspension were group B. The percentage plate recovery (PPR) and corrected count increment (CCI), interleukin-11 (IL-11) and soluble glycoprotein 130 (sgp130) levels were compared between the two groups, and the correlation of PPR and CCI with serum IL-11 and sgp130 levels was analyzed. Multivariate logistic regression was used to analyze the independent risk factors affecting ineffective transfusion in patients with leukemia. After transfusion, PPR and CCI in both groups were significantly higher than those before transfusion (P<0.05). IL-11 was significantly increased in both groups after transfusion, and sgp130 was significantly decreased in the two groups after transfusion (P<0.05). Serum IL-11 level in leukemia patients was positively correlated with PPR and CCI (r=0.7693, P<0.001), (r=0.7760, P<0.001), and serum sgp130 level in leukemia patients was negatively correlated with PPR and CCI (r=-0.7086, P<0.001), (r=-0.7733, P<0.001). There were differences between the effective group and the ineffective group in transfusion frequency, fever, infection and splenomegaly (P<0.05). Fever (OR, 0.382; 95% CI, 0.183-0.972) and infection (OR, 0.367; 95% CI, 0.140-0.956) were independent risk factors for ineffective transfusion. In conclusion, apheresis platelet or mixed multi-person platelet suspension transfusion can significantly improve the disorder of platelet count in patients with leukemia, and improve the clinical efficacy. Fever and infection are independent risk factors leading to ineffective transfusion.
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Affiliation(s)
- Li Chen
- Department of Blood Transfusion, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233000, P.R. China
| | - Hao Zhou
- Department of Blood Transfusion, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233000, P.R. China
| | - Bo Guo
- Department of Blood Transfusion, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233000, P.R. China
| | - Zheng Guan
- Department of Blood Transfusion, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233000, P.R. China
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5
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Evolving therapies for lower-risk myelodysplastic syndromes. Ann Hematol 2020; 99:677-692. [PMID: 32078008 DOI: 10.1007/s00277-020-03963-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 02/10/2020] [Indexed: 12/16/2022]
Abstract
The development in the therapeutic landscape of myelodysplastic syndromes (MDS) has substantially lagged behind other hematologic malignancies with no new drug approvals for MDS for 13 years since the approval of decitabine in the United States in 2006. While therapeutic concepts for MDS patients continue to be primarily defined by clinical-pathologic risk stratification tools such as the International Prognostic Scoring System (IPSS) and its revised version IPSS-R, our understanding of the genetic landscape and the molecular pathogenesis of MDS has greatly evolved over the last decade. It is expected that the therapeutic approach to MDS patients will become increasingly individualized based on prognostic and predictive genetic features and other biomarkers. Herein, we review the current treatment of lower-risk MDS patients and discuss promising agents in advanced clinical testing for the treatment of symptomatic anemia in lower-risk MDS patients such as luspatercept and imetelstat. Lastly, we review the clinical development of new agents and the implications of the wider availability of mutational analysis for the management of individual MDS patients.
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6
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Folkerts H, Wierenga AT, van den Heuvel FA, Woldhuis RR, Kluit DS, Jaques J, Schuringa JJ, Vellenga E. Elevated VMP1 expression in acute myeloid leukemia amplifies autophagy and is protective against venetoclax-induced apoptosis. Cell Death Dis 2019; 10:421. [PMID: 31142733 PMCID: PMC6541608 DOI: 10.1038/s41419-019-1648-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 05/09/2019] [Accepted: 05/13/2019] [Indexed: 12/31/2022]
Abstract
Vacuole membrane protein (VMP1) is a putative autophagy protein, which together with Beclin-1 acts as a molecular switch in activating autophagy. In the present study the role of VMP1 was analysed in CD34+ cells of cord blood (CB) and primary acute myeloid leukemia (AML) cells and cell lines. An increased expression of VMP1 was observed in a subset of AML patients. Functional studies in normal CB CD34+ cells indicated that inhibiting VMP1 expression reduced autophagic-flux, coinciding with reduced expansion of hematopoietic stem and progenitor cells (HSPC), delayed differentiation, increased apoptosis and impaired in vivo engraftment. Comparable results were observed in leukemic cell lines and primary AML CD34+ cells. Ultrastructural analysis indicated that leukemic cells overexpressing VMP1 displayed a reduced number of mitochondrial structures, while the number of lysosomal degradation structures was increased. The overexpression of VMP1 did not affect cell proliferation and differentiation, but increased autophagic-flux and improved mitochondrial quality, which coincided with an increased threshold for venetoclax-induced loss of mitochondrial outer membrane permeabilization (MOMP) and apoptosis. In conclusion, our data indicate that in leukemic cells high VMP1 is involved with mitochondrial quality control.
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Affiliation(s)
- Hendrik Folkerts
- Department of Hematology, Cancer Research Center Groningen, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Albertus T Wierenga
- Department of Hematology, Cancer Research Center Groningen, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Department of Laboratory Medicine, University Medical Center Groningen, Groningen, The Netherlands
| | - Fiona A van den Heuvel
- Department of Hematology, Cancer Research Center Groningen, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Department of Laboratory Medicine, University Medical Center Groningen, Groningen, The Netherlands
| | - Roy R Woldhuis
- Department of Hematology, Cancer Research Center Groningen, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Darlyne S Kluit
- Department of Hematology, Cancer Research Center Groningen, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jennifer Jaques
- Department of Hematology, Cancer Research Center Groningen, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jan Jacob Schuringa
- Department of Hematology, Cancer Research Center Groningen, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Edo Vellenga
- Department of Hematology, Cancer Research Center Groningen, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
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7
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Nurden AT. Acquired Glanzmann thrombasthenia: From antibodies to anti-platelet drugs. Blood Rev 2019; 36:10-22. [PMID: 31010659 DOI: 10.1016/j.blre.2019.03.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/15/2019] [Accepted: 03/19/2019] [Indexed: 02/06/2023]
Abstract
In contrast to the inherited platelet disorder given by mutations in the ITGA2B and ITGB3 genes, mucocutaneous bleeding from a spontaneous inhibition of normally expressed αIIbβ3 characterizes acquired Glanzmann thrombasthenia (GT). Classically, it is associated with autoantibodies or paraproteins that block platelet aggregation without causing a fall in platelet count. However, inhibitory antibodies to αIIbβ3 are widely associated with primary immune thrombocytopenia (ITP), occur in secondary ITP associated with leukemia and related disorders, solid cancers and myeloma, other autoimmune diseases, following organ transplantation while cytoplasmic dysregulation of αIIbβ3 function features in myeloproliferative and myelodysplastic syndromes. Antibodies to αIIbβ3 occur during viral and bacterial infections, while drug-dependent antibodies reacting with αIIbβ3 are a special case. Direct induction of acquired GT is a feature of therapies that block platelets in coronary artery disease. This review looks at these conditions, emphasizing molecular mechanisms, therapy, patient management and future directions for research.
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Affiliation(s)
- Alan T Nurden
- Institut de Rhythmologie et de Modélisation Cardiaque, Plateforme Technologique d'Innovation Biomédicale, Hôpital Xavier Arnozan, Pessac, France.
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Zhang W, Liu C, Wu D, Liang C, Zhang L, Zhang Q, Liu Y, Xia M, Wang H, Su P, Feng S, Han M, Zhou J, Wang F, Jiang E. Decitabine improves platelet recovery by down-regulating IL-8 level in MDS/AML patients with thrombocytopenia. Blood Cells Mol Dis 2019; 76:66-71. [PMID: 30846359 DOI: 10.1016/j.bcmd.2019.02.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 02/02/2019] [Accepted: 02/17/2019] [Indexed: 12/18/2022]
Affiliation(s)
- Wenxia Zhang
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Department of Hematology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei 050000, China
| | - Cuicui Liu
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences & Department of Stem Cells and Regenerative Medicine, Peking Union Medical College, China
| | - Dan Wu
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences & Department of Stem Cells and Regenerative Medicine, Peking Union Medical College, China
| | - Chen Liang
- Hematopoietic Stem Cell Transplant Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Leisheng Zhang
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences & Department of Stem Cells and Regenerative Medicine, Peking Union Medical College, China
| | - Qiuqiu Zhang
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Hematopoietic Stem Cell Transplant Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Yiying Liu
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences & Department of Stem Cells and Regenerative Medicine, Peking Union Medical College, China
| | - Meijuan Xia
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences & Department of Stem Cells and Regenerative Medicine, Peking Union Medical College, China
| | - Hongtao Wang
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences & Department of Stem Cells and Regenerative Medicine, Peking Union Medical College, China
| | - Pei Su
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences & Department of Stem Cells and Regenerative Medicine, Peking Union Medical College, China
| | - Sizhou Feng
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Hematopoietic Stem Cell Transplant Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Mingzhe Han
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Hematopoietic Stem Cell Transplant Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Jiaxi Zhou
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences & Department of Stem Cells and Regenerative Medicine, Peking Union Medical College, China
| | - Fuxu Wang
- Department of Hematology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei 050000, China.
| | - Erlie Jiang
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China; Hematopoietic Stem Cell Transplant Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China.
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Ya F, Tian J, Li Q, Chen L, Ren J, Zhao Y, Wan J, Ling W, Yang Y. Cyanidin-3-O-β-glucoside, a Natural Polyphenol, Exerts Proapoptotic Effects on Activated Platelets and Enhances Megakaryocytic Proplatelet Formation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:10712-10720. [PMID: 30226049 DOI: 10.1021/acs.jafc.8b03266] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This study investigated whether the anthocyanin cyanidin-3-O-β-glucoside (Cy-3-g) could affect platelet apoptosis and proplatelet formation in vitro. Thrombin-stimulated or resting human platelets and Meg-01 megakaryocytes were incubated with Cy-3-g (0, 0.5, 5, or 50 μM). We found that the percentage of the platelet mitochondrial membrane potential treated with 5 and 50 μM Cy-3-g was significantly higher than control (15.50% ± 3.24% and 29.77% ± 4.06% versus 2.76% ± 1.33%, respectively; P < 0.05). Treatment with 5 and 50 μM Cy-3-g significantly increased phosphatidylserine exposure compared with control (40.56% ± 10.53% and 76.62% ± 8.28% versus 15.43% ± 3.93%, respectively; P < 0.05). Moreover, Cy-3-g significantly increased the expression of Bax, Bak, and cytochrome c while markedly decreasing Bcl-xL and Bcl-2 expression as well as stimulating caspase-3, caspase-9, caspase-8, Bid, and gelsolin cleavage in thrombin-activated platelets in a dose-dependent manner ( P < 0.05). However, no significant differences were observed in the apoptosis of resting platelets when treated with Cy-3-g ( P > 0.05). Furthermore, Cy-3-g significantly ( P < 0.05) enhanced cell viability (50 μM versus control, 1.34 ± 0.01 versus 0.35 ± 0.02), the number of colony-forming unit-megakaryocytes (50 μM versus control, 38 ± 3 versus 8 ± 3), CD41 expression (50 μM versus control, 96.80% ± 2.55% versus 25.57% ± 2.86%), DNA ploidy (16N) (50 μM versus control, 19.73% ± 2.34% versus 4.42% ± 1.96%), and proplatelet formation (50 μM versus control, 27.5% ± 3.77% versus 7.67% ± 2.25%) in Meg-01 cells. In conclusion, Cy-3-g promotes activated platelet apoptosis and enhances megakaryocyte proliferation, differentiation, and proplatelet formation in vitro.
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Affiliation(s)
- Fuli Ya
- Department of Nutrition, School of Public Health , Sun Yat-sen University , Guangzhou , Guangdong Province 510080 , China
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health , Guangzhou , Guangdong Province 510080 , China
- Guangdong Engineering Technology Research Center of Nutrition Translation , Guangzhou , Guangdong Province 510080 , China
| | - Jinju Tian
- Department of Pharmaceutical Analysis, School of Pharmaceutical Sciences , Sun Yat-sen University , Guangzhou , Guangdong Province 510006 , China
| | - Qing Li
- Department of Nutrition, School of Public Health , Sun Yat-sen University , Guangzhou , Guangdong Province 510080 , China
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health , Guangzhou , Guangdong Province 510080 , China
- Guangdong Engineering Technology Research Center of Nutrition Translation , Guangzhou , Guangdong Province 510080 , China
| | - Liyi Chen
- Department of Gynecology and Obstetrics, Bao'an Maternal and Child Health Hospital , Jinan University , Shenzhen 518101 , China
| | - Jing Ren
- Baoji Center For Disease Control and Prevention , Baoji , Shaanxi Province 721006 , China
| | - Yimin Zhao
- School of Public Health (Shenzhen) , Sun Yat-sen University , Guangzhou , Guangdong Province 510006 , China
| | - Jianbo Wan
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences , University of Macau , Taipa , Macao 999078 , China
| | - Wenhua Ling
- Department of Nutrition, School of Public Health , Sun Yat-sen University , Guangzhou , Guangdong Province 510080 , China
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health , Guangzhou , Guangdong Province 510080 , China
- Guangdong Engineering Technology Research Center of Nutrition Translation , Guangzhou , Guangdong Province 510080 , China
| | - Yan Yang
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health , Guangzhou , Guangdong Province 510080 , China
- Guangdong Engineering Technology Research Center of Nutrition Translation , Guangzhou , Guangdong Province 510080 , China
- School of Public Health (Shenzhen) , Sun Yat-sen University , Guangzhou , Guangdong Province 510006 , China
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10
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Apoptosis in megakaryocytes and platelets: the life and death of a lineage. Blood 2017; 131:605-610. [PMID: 29259001 DOI: 10.1182/blood-2017-11-742684] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 12/03/2017] [Indexed: 12/17/2022] Open
Abstract
Despite their profoundly different cellular composition, size, and function, megakaryocytes and platelets both depend on restraint of the intrinsic (or "mitochondrial") apoptosis pathway by BCL-2 family prosurvival proteins for their development and viability. Activation of the pathway contributes to the clearance of megakaryocytes following platelet shedding and constrains platelet lifespan in the circulation. Important questions remain as to how apoptosis is initiated in these cells at steady state and in response to pathophysiological insults.
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11
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Li W, Morrone K, Kambhampati S, Will B, Steidl U, Verma A. Thrombocytopenia in MDS: epidemiology, mechanisms, clinical consequences and novel therapeutic strategies. Leukemia 2015; 30:536-44. [PMID: 26500138 DOI: 10.1038/leu.2015.297] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 08/03/2015] [Indexed: 12/14/2022]
Abstract
Thrombocytopenia is commonly seen in myelodysplastic syndrome (MDS) patients, and bleeding complications are a major cause of morbidity and mortality. Thrombocytopenia is an independent factor for decreased survival and has been incorporated in newer prognostic scoring systems. The mechanisms of thrombocytopenia are multifactorial and involve a differentiation block of megakaryocytic progenitor cells, leading to dysplastic, hypolobated and microscopic appearing megakaryocytes or increased apoptosis of megakaryocytes and their precursors. Dysregulated thrombopoietin (TPO) signaling and increased platelet destruction through immune or nonimmune mechanisms are frequently observed in MDS. The clinical management of patients with low platelet counts remains challenging and approved chemotherapeutic agents such as lenalidomide and azacytidine can also lead to a transient worsening of thrombocytopenia. Platelet transfusion is the only supportive treatment option currently available for clinically significant thrombocytopenia. The TPO receptor agonists romiplostim and eltrombopag have shown clinical activity in clinical trials in MDS. In addition to thrombopoietic effects, eltrombopag can inhibit leukemic cell proliferation via TPO receptor-independent effects. Other approaches such as treatment with cytokines, immunomodulating drugs and signal transduction inhibitors have shown limited activity in selected groups of MDS patients. Combination trials of approved agents with TPO agonists are ongoing and hold promise for this important clinical problem.
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Affiliation(s)
- W Li
- Department of Medicine, Albert Einstein College of Medicine/Jacobi Medical Center, Bronx, NY, USA
| | - K Morrone
- Department of Pediatrics, Albert Einstein College of Medicine/Montefiore Medical Center, Bronx, NY, USA
| | - S Kambhampati
- Department of Medicine, University of Kansas Medical Center, Kansas City, KS, USA
| | - B Will
- Division of Hemato-Oncology, Department of Oncology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - U Steidl
- Division of Hemato-Oncology, Department of Oncology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - A Verma
- Division of Hemato-Oncology, Department of Oncology, Albert Einstein College of Medicine, Bronx, NY, USA
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12
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Folkerts H, Hazenberg CL, Houwerzijl EJ, van den Heuvel FA, Mulder AB, van der Want JJ, Vellenga E. Erythroid progenitors from patients with low-risk myelodysplastic syndromes are dependent on the surrounding micro environment for their survival. Exp Hematol 2015; 43:215-222.e2. [DOI: 10.1016/j.exphem.2014.11.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 10/16/2014] [Accepted: 11/11/2014] [Indexed: 10/24/2022]
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13
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Abstract
Myelodysplastic syndromes (MDS) are clinically, genetically, and molecularly heterogeneous neoplastic diseases characterized by ineffective hematopoiesis leading to peripheral cytopenias. The severity of cytopenias influences oucome and is considered in prognostic scoring systems; thrombocytopenia, although not the most frequently observed at disease onset, is estimated to affect 40%-80% of MDS patients. As thrombocytopenia in MDS is determined by premature marrow destruction and programmed cell death, the use of thrombomimetic agents has been proposed in order to stimulate megakaryocyte differentation and proliferation. After early attempts of therapy of thrombocytopenic MDS patients with thrombopoietin and interleukin (IL)-11, clinical trials testing the activity of romiplostim and eltrombopag have been recently designed and have demonstrated good tolerability and efficacy in re-inducing megakaryocytopoiesis and in lowering the number of hemorragic events. The number of MDS patients receiving such treatments is still limited and a broader evaluation of the long-term effects and safety of these agents is ongoing.
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Affiliation(s)
- Valeria Santini
- Hematology, AOU Careggi, University of Florence, Florence, Italy.
| | - Pierre Fenaux
- Service d'Hématologie Séniors, Hôpital St Louis, Assistance Publique, Hôpitaux de Paris, Université Paris 7, Paris, France
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14
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Walenda T, Stiehl T, Braun H, Fröbel J, Ho AD, Schroeder T, Goecke TW, Rath B, Germing U, Marciniak-Czochra A, Wagner W. Feedback signals in myelodysplastic syndromes: increased self-renewal of the malignant clone suppresses normal hematopoiesis. PLoS Comput Biol 2014; 10:e1003599. [PMID: 24763223 PMCID: PMC3998886 DOI: 10.1371/journal.pcbi.1003599] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 03/18/2014] [Indexed: 12/20/2022] Open
Abstract
Myelodysplastic syndromes (MDS) are triggered by an aberrant hematopoietic stem cell (HSC). It is, however, unclear how this clone interferes with physiologic blood formation. In this study, we followed the hypothesis that the MDS clone impinges on feedback signals for self-renewal and differentiation and thereby suppresses normal hematopoiesis. Based on the theory that the MDS clone affects feedback signals for self-renewal and differentiation and hence suppresses normal hematopoiesis, we have developed a mathematical model to simulate different modifications in MDS-initiating cells and systemic feedback signals during disease development. These simulations revealed that the disease initiating cells must have higher self-renewal rates than normal HSCs to outcompete normal hematopoiesis. We assumed that self-renewal is the default pathway of stem and progenitor cells which is down-regulated by an increasing number of primitive cells in the bone marrow niche – including the premature MDS cells. Furthermore, the proliferative signal is up-regulated by cytopenia. Overall, our model is compatible with clinically observed MDS development, even though a single mutation scenario is unlikely for real disease progression which is usually associated with complex clonal hierarchy. For experimental validation of systemic feedback signals, we analyzed the impact of MDS patient derived serum on hematopoietic progenitor cells in vitro: in fact, MDS serum slightly increased proliferation, whereas maintenance of primitive phenotype was reduced. However, MDS serum did not significantly affect colony forming unit (CFU) frequencies indicating that regulation of self-renewal may involve local signals from the niche. Taken together, we suggest that initial mutations in MDS particularly favor aberrant high self-renewal rates. Accumulation of primitive MDS cells in the bone marrow then interferes with feedback signals for normal hematopoiesis – which then results in cytopenia. Myelodysplastic syndromes are diseases which are characterized by ineffective blood formation. There is accumulating evidence that they are caused by an aberrant hematopoietic stem cell. However, it is yet unclear how this malignant clone suppresses normal hematopoiesis. To this end, we generated mathematical models under the assumption that feedback signals regulate self-renewal and proliferation of normal and diseased stem cells. The simulations demonstrate that the malignant cells must have particularly higher self-renewal rates than normal stem cells – rather than higher proliferation rates. On the other hand, down-regulation of self-renewal by the increasing number of malignant cells in the bone marrow niche can explain impairment of normal blood formation. In fact, we show that serum of patients with myelodysplastic syndrome, as compared to serum of healthy donors, stimulates proliferation and moderately impacts on maintenance of hematopoietic stem and progenitor cells in vitro. Thus, aberrant high self-renewal rates of the malignant clone seem to initiate disease development; suppression of normal blood formation is then caused by a rebound effect of feedback signals which down-regulate self-renewal of normal stem and progenitor cells as well.
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Affiliation(s)
- Thomas Walenda
- Helmholtz Institute for Biomedical Engineering, RWTH Aachen University Medical School, Aachen, Germany
| | - Thomas Stiehl
- Interdisciplinary Center of Scientific Computing (IWR), Institute of Applied Mathematics, University of Heidelberg, Heidelberg, Germany
| | - Hanna Braun
- Helmholtz Institute for Biomedical Engineering, RWTH Aachen University Medical School, Aachen, Germany
| | - Julia Fröbel
- Department of Hematology, Oncology and Clinical Immunology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Anthony D. Ho
- Department of Medicine V, Medical Center, University of Heidelberg, Heidelberg, Germany
| | - Thomas Schroeder
- Department of Hematology, Oncology and Clinical Immunology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Tamme W. Goecke
- Department of Obstetrics and Gynecology, RWTH Aachen University Medical School, Aachen, Germany
| | - Björn Rath
- Department for Orthopedics, RWTH Aachen University Medical School, Aachen, Germany
| | - Ulrich Germing
- Department of Hematology, Oncology and Clinical Immunology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Anna Marciniak-Czochra
- Interdisciplinary Center of Scientific Computing (IWR), Institute of Applied Mathematics, University of Heidelberg, Heidelberg, Germany
| | - Wolfgang Wagner
- Helmholtz Institute for Biomedical Engineering, RWTH Aachen University Medical School, Aachen, Germany
- * E-mail:
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15
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Platelet production proceeds independently of the intrinsic and extrinsic apoptosis pathways. Nat Commun 2014; 5:3455. [PMID: 24632563 DOI: 10.1038/ncomms4455] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 02/14/2014] [Indexed: 12/18/2022] Open
Abstract
BH3 mimetic drugs that target BCL-2 family pro-survival proteins to induce tumour cell apoptosis represent a new era in cancer therapy. Clinical trials of navitoclax (ABT-263, which targets BCL-2, BCL-XL and BCL-W) have shown great promise, but encountered dose-limiting thrombocytopenia. Recent work has demonstrated that this is due to the inhibition of BCL-XL, which is essential for platelet survival. These findings raise new questions about the established model of platelet shedding by megakaryocytes, which is thought to be an apoptotic process. Here we generate mice with megakaryocyte-specific deletions of the essential mediators of extrinsic (Caspase-8) and intrinsic (BAK/BAX) apoptosis. We show that megakaryocytes possess a Fas ligand-inducible extrinsic apoptosis pathway. However, Fas activation does not stimulate platelet production, rather, it triggers Caspase-8-mediated killing. Combined loss of Caspase-8/BAK/BAX does not impair thrombopoiesis, but can protect megakaryocytes from death in mice infected with lymphocytic choriomeningitis virus. Thus, apoptosis is dispensable for platelet biogenesis.
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16
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Abstract
The role of apoptotic pathways in the development and function of the megakaryocyte lineage has generated renewed interest in recent years. This has been driven by the advent of BH3 mimetic drugs that target BCL2 family proteins to induce apoptosis in tumour cells: agents such as ABT-263 (navitoclax, which targets BCL2, BCL-XL [BCL2L1] and BCL2L2) and ABT-199 (a BCL2-specific agent) are showing great promise in early stage clinical trials. However, the major dose-limiting toxicity of navitoclax has proven to be thrombocytopenia, an on-target effect of inhibiting BCL-XL . It transpires that the anucleate platelet contains a classical intrinsic apoptosis pathway, which at steady state regulates its life span in the circulation. BCL-XL is the critical pro-survival protein that restrains apoptosis and maintains platelet viability. These findings have paved the way to a deeper understanding of apoptotic pathways and processes in platelets, and their precursor cell, the megakaryocyte.
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Affiliation(s)
- Benjamin T Kile
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Vic., Australia; Department of Medical Biology, The University of Melbourne, Parkville, Vic., Australia
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17
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Martín M, de Paz R, Jiménez-Yuste V, Fernández Bello I, García Arias Salgado E, Alvarez MT, Butta NV. Platelet apoptosis and agonist-mediated activation in myelodysplastic syndromes. Thromb Haemost 2013; 109:909-19. [PMID: 23407717 DOI: 10.1160/th12-09-0670] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 01/21/2013] [Indexed: 12/18/2022]
Abstract
Patients with myelodysplastic syndromes (MDS) have a defect in the differentiation of bone marrow multipotent progenitor cells. Thrombocytopenia in MDS patients may be due to premature megakaryocyte death, but platelet apoptotic mechanisms may also occur. This study aimed to study function and apoptotic state of platelets from MDS patients with different platelet count. Reticulated platelets, platelet activation, activated caspases and annexin-V binding were evaluated by flow cytometry. Pro-apoptotic Bax and Bak proteins were determined by western blots and plasma thrombopoietin by ELISA. Microparticle-associated procoagulant activity and thrombin generation capacity of plasma were determined by an activity kit and calibrated automated thrombography, respectively. High plasma thrombopoietin levels and low immature circulating platelet count showed a pattern of hypoplastic thrombocytopenia in MDS patients. Platelets from MDS patients showed reduced activation capacity and more apoptosis signs than controls. Patients with the lowest platelet count showed less platelet activation and the highest extent of platelet apoptosis. On this basis, patients with thrombocytopenia should suffer more haemorrhagic episodes than is actually observed. Consequently, we tested whether there were some compensatory mechanisms to counteract their expected bleeding tendency. Microparticle-associated procoagulant activity was enhanced in MDS patients with thrombocytopenia, whereas their plasma thrombin generation capacity was similar to control group. This research shows a hypoplastic thrombocytopenia that platelets from MDS patients possess an impaired ability to be stimulated and more apoptosis markers than those from healthy controls, indicating that MDS is a stem cell disorder, and then, both number and function of progeny cells, might be affected.
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Affiliation(s)
- M Martín
- Haematology Unit, Hospital Universitario La Paz-IDIPaz, Madrid, Spain.
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18
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Dickinson M. Supportive care for thrombocytopenia in patients receiving treatment for myelodysplasia: a challenge for the future. Leuk Lymphoma 2013; 54:221-3. [DOI: 10.3109/10428194.2012.738817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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19
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Abstract
Abstract
Mature megakaryocytes depend on the function of Bcl-xL, a member of the Bcl-2 family of prosurvival proteins, to proceed safely through the process of platelet shedding. Despite this, loss of Bcl-xL does not prevent the growth and maturation of megakaryocytes, suggesting redundancy with other prosurvival proteins. We therefore generated mice with a megakaryocyte-specific deletion of Mcl-1, which is known to be expressed in megakaryocytes. Megakaryopoiesis, platelet production, and platelet lifespan were unperturbed in Mcl-1Pf4Δ/Pf4Δ animals. However, treatment with ABT-737, a BH3 mimetic compound that inhibits the prosurvival proteins Bcl-2, Bcl-xL, and Bcl-w resulted in the complete ablation of megakaryocytes and platelets. Genetic deletion of both Mcl-1 and Bcl-xL in megakaryocytes resulted in preweaning lethality. Megakaryopoiesis in Bcl-xPf4Δ/Pf4ΔMcl-1Pf4Δ/Pf4Δ embryos was severely compromised, and these animals exhibited ectopic bleeding. Our studies indicate that the combination of Bcl-xL and Mcl-1 is essential for the viability of the megakaryocyte lineage.
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20
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Gilli SCO, de Souza Medina S, de Castro V, Fernandes LGR, Saad STO. Platelet associated IgG may be related with thrombocytopenia in patients with myelodysplastic syndromes. Leuk Res 2012; 36:554-9. [DOI: 10.1016/j.leukres.2011.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 10/04/2011] [Accepted: 10/07/2011] [Indexed: 01/13/2023]
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21
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Sandes AF, Yamamoto M, Matarraz S, Chauffaille MDLLF, Quijano S, López A, Oguro T, Kimura EYS, Orfao A. Altered immunophenotypic features of peripheral blood platelets in myelodysplastic syndromes. Haematologica 2012; 97:895-902. [PMID: 22271903 DOI: 10.3324/haematol.2011.057158] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Multiparameter flow cytometric analysis of bone marrow and peripheral blood cells has proven to be of help in the diagnostic workup of myelodysplastic syndromes. However, the usefulness of flow cytometry for the detection of megakaryocytic and platelet dysplasia has not yet been investigated. The aim of this pilot study was to evaluate by flow cytometry the diagnostic and prognostic value of platelet dysplasia in myelodysplastic syndromes. DESIGN AND METHODS We investigated the pattern of expression of distinct surface glycoproteins on peripheral blood platelets from a series of 44 myelodysplastic syndrome patients, 20 healthy subjects and 19 patients with platelet alterations associated to disease conditions other than myelodysplastic syndromes. Quantitative expression of CD31, CD34, CD36, CD41a, CD41b, CD42a, CD42b and CD61 glycoproteins together with the PAC-1, CD62-P, fibrinogen and CD63 platelet activation-associated markers and platelet light scatter properties were systematically evaluated. RESULTS Overall, flow cytometry identified multiple immunophenotypic abnormalities on platelets of myelodysplastic syndrome patients, including altered light scatter characteristics, over-and under expression of specific platelet glycoproteins and asynchronous expression of CD34; decreased expression of CD36 (n = 5), CD42a (n = 1) and CD61 (n = 2), together with reactivity for CD34 (n = 1) were only observed among myelodysplastic syndrome cases, while other alterations were also found in other platelet disorders. Based on the overall platelet alterations detected for each patient, an immunophenotypic score was built which identified a subgroup of myelodysplastic syndrome patients with a high rate of moderate to severe alterations (score>1.5; n = 16) who more frequently showed thrombocytopenia, megakaryocytic dysplasia and high-risk disease, together with a shorter overall survival. CONCLUSIONS Our results show the presence of altered phenotypes by flow cytometry on platelets from around half of the myelodysplastic syndrome patients studied. If confirmed in larger series of patients, these findings may help refine the diagnostic and prognostic assessment of this group of disorders.
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Affiliation(s)
- Alex F Sandes
- Disciplina de Hematologia e Hemoterapia, Departamento de Oncologia Clínica, Universidade Federal de São Paulo, UNIFESP, R. Botucatu 740, V. Clementino, 04023-900, São Paulo, Brazil.
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22
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Mavroudi I, Pyrovolaki K, Pavlaki K, Kozana A, Psyllaki M, Kalpadakis C, Pontikoglou C, Papadaki HA. Effect of the nonpeptide thrombopoietin receptor agonist eltrombopag on megakaryopoiesis of patients with lower risk myelodysplastic syndrome. Leuk Res 2011; 35:323-8. [DOI: 10.1016/j.leukres.2010.06.029] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2010] [Revised: 06/28/2010] [Accepted: 06/29/2010] [Indexed: 12/24/2022]
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23
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Eckly A, Rinckel JY, Laeuffer P, Cazenave JP, Lanza F, Gachet C, Léon C. Proplatelet formation deficit and megakaryocyte death contribute to thrombocytopenia in Myh9 knockout mice. J Thromb Haemost 2010; 8:2243-51. [PMID: 20695978 DOI: 10.1111/j.1538-7836.2010.04009.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Inactivation of the mouse Myh9 gene (Myh9Δ) or its mutation in MYH9-related diseases leads to macrothrombocytopenia. Paradoxically, previous studies using in vitro differentiated megakaryocytes showed an increased capacity for proplatelet formation when myosin was absent or inhibited. METHODS To explore the origin of the thrombocytopenia induced by myosin deficiency, we studied proplatelet formation using bone marrow explants of wild-type (WT) and Myh9Δ mouse where megakaryocytes have matured in their native environment. RESULTS AND DISCUSSION A dramatic decrease in the number and complexity of proplatelets was observed in megakaryocytes from Myh9Δ mice, while inhibition of myosin activity by blebbistatin increased proplatelet formation from WT mature megakaryocytes. Moreover, Myh9Δ megakaryocytes had a smaller size than the WT cells. These data indicate that myosin deficiency acts negatively on proplatelet formation, probably by impairing in situ megakaryocyte maturation, while myosin activity is dispensable at the latest stage of proplatelet formation. In addition, ultrastructural examination of Myh9Δ bone marrow revealed an increased proportion of megakaryocytes exhibiting signs of non-apoptotic cell death as compared with the WT mice. CONCLUSION These data indicate that thrombocytopenia in Myh9Δ mice results from defective development of megakaryocyte size, impaired proplatelet formation and increased cell death.
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Affiliation(s)
- A Eckly
- UMR_S949 INSERM-Université de Strasbourg, Etablissement Français du Sang-Alsace, Strasbourg, France
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24
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Olcay L, Tuncer AM, Okur H, Erdemli E, Uysal Z, Cetin M, Duru F, Cetinkaya DU. Excessive naked megakaryocyte nuclei in myelodysplastic syndrome mimicking idiopathic thrombocytopenic purpura: a complicated pre- and post-transplantation course. Pediatr Hematol Oncol 2009; 26:387-97. [PMID: 19657988 DOI: 10.3109/08880010902891891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A boy 3 years 7 months old with thrombocytopenia and history of intracranial hemorrhage who underwent bone marrow transplantation is presented. He was refractory to steroids, immunoglobulin G, vincristine, azathioprine, cyclosporine A, interleukin-11, chemotherapy, and splenectomy. Idiopathic thrombocytopenic purpura was excluded by light /electron microscopic and flow cytometric findings; the diagnosis of refractory cytopenia, a subgroup of pediatric myelodysplastic syndrome, was made. Naked megakaryocyte nuclei were 55.38 +/- 28.2% vs. 31.67 +/- 23.22% of all megakaryocytes in the patient and the control group of 9 patients with idiopathic thrombocytopenic purpura, respectively (p = .016). The posttransplatation course was complicated by delayed platelet engraftment, bronchiolitis obliterans associated with pneumocystis carinii pneumonia, which resolved completely.
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Affiliation(s)
- Lale Olcay
- Dr A.Y. Ankara Oncology Research and Education Hospital, Unit of Pediatric Hematology, Demetevler, Ankara, Turkey.
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25
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Abstract
The evolution of platelet directed pharmacotherapy in the prevention and treatment of patients with thrombotic disorders is based soundly on a rapidly expanding knowledge of platelet biology. Traditionally viewed, throughout most of its relatively brief history in medicine, as an anucleate, passive contributor to hemostasis, a more contemporary perspective acknowledges platelets as complex, multidimensional cells that participate actively in coagulation, vascular repair, angiogenesis and thrombosis within the micro and the macro-circulatory systems. Herein, we consider platelet-directed pharmacotherapy from these fundamental, biology-based exemplars--megakaryocytes, signal transduction and the platelet--coagulation protease interface. We also highlight the emerging biopharmacology platform of oligonucleotide platelet adhesion antagonists and their complementary antidotes.
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Affiliation(s)
- R C Becker
- Division of Hematology, Duke University School of Medicine, Duke Clinical Research Institute, Durham, NC 27705, USA.
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26
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Abstract
Myelodysplastic syndromes (MDS) are a group of hematopoietic stem cell disorders characterized by ineffective hematopoeisis and an increased risk of transforming to acute myelogenous leukemia (AML). Determining the molecular basis of the disease has been hampered by its heterogeneity. Thrombocytopenia is often a manifestation of MDS and needs to be monitored and treated accordingly. Treating the underlying disorder with a variety of differentiation and immunosuppressive agents alleviates the problem in a small percentage of patients but more often complicates the issue. Several treatments used for primary immune thrombocytopenic purpura (ITP) have been tried in MDS patients, though with only modest success rates. Preliminary studies suggest that the use of a thrombopoietic growth factor may afford substantial increases in platelet levels without excessive deleterious side effects. Primary myelofibrosis (MF) is a chronic myeloproliferative disorder associated with hepatosplenomegaly and refractory cytopenias. Immunomodulatory agents have shown promise in treating the anemia associated with this MF. However, there are currently no standard therapies to treat the thrombocytopenia that is often found in patients with this disease.
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Affiliation(s)
- Adam M Boruchov
- Saint Francis Regional Cancer Center, University of Connecticut School of Medicine, Hartford, CT 06105, USA.
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27
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Houwerzijl EJ, Pol HWD, Blom NR, van der Want JJL, de Wolf JTM, Vellenga E. Erythroid precursors from patients with low-risk myelodysplasia demonstrate ultrastructural features of enhanced autophagy of mitochondria. Leukemia 2009; 23:886-91. [PMID: 19148135 DOI: 10.1038/leu.2008.389] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Revised: 11/06/2008] [Accepted: 11/25/2008] [Indexed: 01/10/2023]
Abstract
Recent studies in erythroid cells have shown that autophagy is an important process for the physiological clearance of mitochondria during terminal differentiation. However, autophagy also plays an important role in removing damaged and dysfunctional mitochondria. Defective mitochondria and impaired erythroid maturation are important characteristics of low-risk myelodysplasia. In this study we therefore questioned whether the autophagic clearance of mitochondria might be altered in erythroblasts from patients with refractory anemia (RA, n=3) and RA with ringed sideroblasts (RARS, n=6). Ultrastructurally, abnormal and iron-laden mitochondria were abundant, especially in RARS patients. A large proportion (52+/-16%) of immature and mature myelodysplastic syndrome (MDS) erythroblasts contained cytoplasmic vacuoles, partly double membraned and positive for lysosomal marker LAMP-2 and mitochondrial markers, findings compatible with autophagic removal of dysfunctional mitochondria. In healthy controls only mature erythroblasts comprised these vacuoles (12+/-3%). These findings were confirmed morphometrically showing an increased vacuolar surface in MDS erythroblasts compared to controls (P<0.0001). In summary, these data indicate that MDS erythroblasts show features of enhanced autophagy at an earlier stage of erythroid differentiation than in normal controls. The enhanced autophagy might be a cell protective mechanism to remove defective iron-laden mitochondria.
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Affiliation(s)
- E J Houwerzijl
- Department of Hematology, University Medical Center Groningen, Groningen, The Netherlands.
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28
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Penna I, Du H, Ferriani R, Taylor HS. Calpain5 expression is decreased in endometriosis and regulated by HOXA10 in human endometrial cells. Mol Hum Reprod 2008; 14:613-8. [PMID: 18829447 PMCID: PMC2734161 DOI: 10.1093/molehr/gan055] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 09/16/2008] [Accepted: 09/19/2008] [Indexed: 11/14/2022] Open
Abstract
Calpains have been implicated in the regulation of apoptosis. Here, we identified Calpain5 as a target of HOXA10 transcriptional regulation in endometrial cells as well as its aberrant regulation in endometriosis. Histologically confirmed biopsies of endometriosis were obtained from 20 women. Eutopic endometrium was collected by endometrial biopsy from 30 controls and from the 20 subjects with endometriosis. First trimester decidual samples were obtained from five subjects at the time of pregnancy termination. Immunohistochemistry was used to identify Calpain5 expression. Calpain5 was expressed in endometrial stromal and glandular cells throughout the menstrual cycle and in decidua. Calpain5 protein expression was decreased in both stromal and glandular cells from women with endometriosis compared with that of fertile controls. Human endometrial stromal and epithelial cell lines were transfected with pcDNA/HOXA10, HOXA10 siRNA or respective controls. Quantitative real-time RT-PCR was performed to determine expression of HOXA10 and Calpain5 in each group. Transfection of HESC cells with an HOXA10 expression construct led to increased Calpain5 expression, whereas transfection with siRNA resulted in decreased expression. In conclusion, Calpain5 expression is regulated by HOXA10. Calpain5 expression was decreased in endometriosis likely as a result of decreased HOXA10 expression. Decreased apoptosis in endometrial cells may promote the development of endometriosis through a pathway involving HOXA10, Calpain5 and caspase.
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Affiliation(s)
- Ivan Penna
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
- Department of Obstetrics and Gynecology of Ribeirão Preto Medical School, São Paulo University, Ribeirão Preto, SP, Brazil
| | - Hongling Du
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Rui Ferriani
- Department of Obstetrics and Gynecology of Ribeirão Preto Medical School, São Paulo University, Ribeirão Preto, SP, Brazil
| | - Hugh S. Taylor
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
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29
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Tiu RV, Sekeres MA. The role of AMG-531 in the treatment of thrombocytopenia in idiopathic thrombocytopenic purpura and myelodysplastic syndromes. Expert Opin Biol Ther 2008; 8:1021-30. [DOI: 10.1517/14712598.8.7.1021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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30
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Economopoulou C, Pappa V, Kontsioti F, Papageorgiou S, Kapsimali V, Papasteriadi C, Economopoulou P, Papageorgiou E, Dervenoulas J, Economopoulos T. Analysis of apoptosis regulatory genes expression in the bone marrow (BM) of adult de novo Myelodysplastic Syndromes (MDS). Leuk Res 2008; 32:61-9. [PMID: 17597205 DOI: 10.1016/j.leukres.2007.04.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2007] [Revised: 04/04/2007] [Accepted: 04/06/2007] [Indexed: 11/22/2022]
Abstract
The aim of the present study was to examine caspases, granzyme B and bcl-2 family mRNA expression and the degree of apoptosis in the bone marrow (BM) of 46 Myelodysplastic Syndromes (MDS) and to correlate our findings with clinical parameters. The degree of apoptosis was determined by Annexin V, whereas expression of genes was determined using a multiprobe RNase Protection System. A positive correlation was found between caspases 8, 5, 3, 2, 1 and the level of apoptosis. bfl1 and mcl1 levels were significantly higher in patients with BM blasts >5%. Cases with ratio of bid expression >1 compared to normal pool were associated with IPSS values < or =1.
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Affiliation(s)
- C Economopoulou
- Attikon University Hospital, 2nd Propedeutic Clinic of Internal., 1 Rimini St., Athens, Haidari, Greece.
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31
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Braun T, Carvalho G, Grosjean J, Ades L, Fabre C, Boehrer S, Debili N, Fenaux P, Kroemer G. Differentiating megakaryocytes in myelodysplastic syndromes succumb to mitochondrial derangement without caspase activation. Apoptosis 2007; 12:1101-8. [PMID: 17245643 DOI: 10.1007/s10495-006-0030-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Myelodysplastic syndromes (MDS) constitute a preneoplastic condition in which potentially malignant cancer stem cells continuously die during differentiation. This MDS-associated cell death often involves caspase-3 activation, yet can also occur without caspase activation, for instance in differentiating megakaryocytes (MK). We investigated, the mechanisms through which MK from MDS patients undergo premature cell death. While polyploid, mature MK from healthy subjects or MDS patients manifested caspase-3 activation during terminal differentiation, freshly isolated, immature MK from MDS died without caspase-3 activation. Similarly, purified bone marrow CD34(+) cells from MDS patients that were driven into MK differentiation in vitro died without caspase-3 activation at an immature stage, before polyploidization. The premature death of MDS MK was accompanied by the mitochondrial release of cytochrome c, Smac/DIABLO and endonuclease G, a caspase-independent death effector, as well loss of the mitochondrial membrane potential and plasma membrane phosphatidylserine exposure before definitive loss of viability. Thus, a stereotyped pattern of mitochondrial alterations accompanies differentiation-associated MK death in MDS.
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32
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Fuhler GM, Blom NR, Coffer PJ, Drayer AL, Vellenga E. The reduced GM-CSF priming of ROS production in granulocytes from patients with myelodysplasia is associated with an impaired lipid raft formation. J Leukoc Biol 2006; 81:449-57. [PMID: 17079651 DOI: 10.1189/jlb.0506311] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Patients with myelodysplasia (MDS) show an impaired reactive oxygen species (ROS) production in response to fMLP stimulation of GM-CSF-primed neutrophils. In this study, we investigated the involvement of lipid rafts in this process and showed that treatment of neutrophils with the lipid raft-disrupting agent methyl-beta-cyclodextrin abrogates fMLP-induced ROS production and activation of ERK1/2 and protein kinase B/Akt, two signal transduction pathways involved in ROS production in unprimed and GM-CSF-primed neutrophils. We subsequently showed that there was a decreased presence of Lyn, gp91(phox), and p22(phox) in lipid raft fractions from neutrophils of MDS. Furthermore, the plasma membrane expression of the lipid raft marker GM1, which increases upon stimulation of GM-CSF-primed cells with fMLP, was reduced significantly in MDS patients. By electron microscopy, we showed that the fMLP-induced increase in GM1 expression in GM-CSF-primed cells was a result of de novo synthesis, which was less efficient in MDS neutrophils. Taken together, these data indicate an involvement of lipid rafts in activation of signal transduction pathways leading to ROS production and show that in MDS neutrophils, an impaired lipid raft formation in GM-CSF-primed cells results in an impaired ROS production.
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Affiliation(s)
- Gwenny M Fuhler
- Division of Hematology, Department of Medicine, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
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33
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Fontenay M, Cathelin S, Amiot M, Gyan E, Solary E. Mitochondria in hematopoiesis and hematological diseases. Oncogene 2006; 25:4757-67. [PMID: 16892088 DOI: 10.1038/sj.onc.1209606] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Mitochondria are involved in hematopoietic cell homeostasis through multiple ways such as oxidative phosphorylation, various metabolic processes and the release of cytochrome c in the cytosol to trigger caspase activation and cell death. In erythroid cells, the mitochondrial steps in heme synthesis, iron (Fe) metabolism and Fe-sulfur (Fe-S) cluster biogenesis are of particular importance. Mutations in the specific delta-aminolevulinic acid synthase (ALAS) 2 isoform that catalyses the first and rate-limiting step in heme synthesis pathway in the mitochondrial matrix, lead to ineffective erythropoiesis that characterizes X-linked sideroblastic anemia (XLSA), the most common inherited sideroblastic anemia. Mutations in the adenosine triphosphate-binding cassette protein ABCB7, identified in XLSA with ataxia (XLSA-A), disrupt the maturation of cytosolic (Fe-S) clusters, leading to mitochondrial Fe accumulation. In addition, large deletions in mitochondrial DNA, whose integrity depends on a specific DNA polymerase, are the hallmark of Pearson's syndrome, a rare congenital disorder with sideroblastic anemia. In acquired myelodysplastic syndromes at early stage, exacerbation of physiological pathways involving caspases and the mitochondria in erythroid differentiation leads to abnormal activation of a mitochondria-mediated apoptotic cell death pathway. In contrast, oncogenesis-associated changes at the mitochondrial level can alter the apoptotic response of transformed hematopoietic cells to chemotherapeutic agents. Recent findings in mitochondria metabolism and functions open new perspectives in treating hematopoietic cell diseases, for example various compounds currently developed to trigger tumor cell death by directly targeting the mitochondria could prove efficient as either cytotoxic drugs or chemosensitizing agents in treating hematological malignancies.
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Affiliation(s)
- M Fontenay
- Inserm U567, Institut Cochin, Department of Hematology, Paris, Cedex, France
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Houwerzijl EJ, Blom NR, van der Want JJL, Vellenga E, de Wolf JTM. Megakaryocytic dysfunction in myelodysplastic syndromes and idiopathic thrombocytopenic purpura is in part due to different forms of cell death. Leukemia 2006; 20:1937-42. [PMID: 16990774 DOI: 10.1038/sj.leu.2404385] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Platelet production requires compartmentalized caspase activation within megakaryocytes. This eventually results in platelet release in conjunction with apoptosis of the remaining megakaryocyte. Recent studies have indicated that in low-risk myelodysplastic syndromes (MDS) and idiopathic thrombocytopenic purpura (ITP), premature cell death of megakaryocytes may contribute to thrombocytopenia. Different cell death patterns have been identified in megakaryocytes in these disorders. Growing evidence suggests that, besides apoptosis, necrosis and autophagic cell death, may also be programmed. Therefore, programmed cell death (PCD) can be classified in apoptosis, a caspase-dependent process, apoptosis-like, autophagic and necrosis-like PCD, which are predominantly caspase-independent processes. In MDS, megakaryocytes show features of necrosis-like PCD, whereas ITP megakaryocytes demonstrate predominantly characteristics of apoptosis-like PCD (para-apoptosis). Triggers for these death pathways are largely unknown. In MDS, the interaction of Fas/Fas-ligand might be of importance, whereas in ITP antiplatelet autoantibodies recognizing common antigens on megakaryocytes and platelets might be involved. These findings illustrate that cellular death pathways in megakaryocytes are recruited in both physiological and pathological settings, and that different forms of cell death can occur in the same cell depending on the stimulus and the cellular context. Elucidation of the underlying mechanisms might lead to novel therapeutic interventions.
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Affiliation(s)
- E J Houwerzijl
- Department of Hematology, University Medical Center Groningen, Groningen, The Netherlands.
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