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Boucher AA, Dayton VJ, Pratt AR, Nassar NN, Elgammal Y, Kalfa TA. Three-generation female cohort with macrocytic anemia and iron overload. Am J Hematol 2024. [PMID: 39329459 DOI: 10.1002/ajh.27489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2024] [Revised: 09/02/2024] [Accepted: 09/12/2024] [Indexed: 09/28/2024]
Affiliation(s)
- Alexander A Boucher
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota, USA
- Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, USA
| | - Vanessa J Dayton
- Laboratory Medicine and Pathology, Hennepin County Medical Center, Hennepin Healthcare Research Institute, Minneapolis, Minnesota, USA
| | - Annaliisa R Pratt
- Laboratory Medicine and Pathology, Hennepin County Medical Center, Hennepin Healthcare Research Institute, Minneapolis, Minnesota, USA
| | - Nicolas N Nassar
- Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati Medical School, Cincinnati, Ohio, USA
| | - Yasmin Elgammal
- Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Theodosia A Kalfa
- Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati Medical School, Cincinnati, Ohio, USA
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2
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Abba ML, Riabov V, Nowak D, Hofmann WK, Boch T. Understanding iron homeostasis in MDS: the role of erythroferrone. Front Oncol 2024; 14:1404817. [PMID: 38835379 PMCID: PMC11148345 DOI: 10.3389/fonc.2024.1404817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 05/07/2024] [Indexed: 06/06/2024] Open
Abstract
Myelodysplastic neoplasms (MDS) are a heterogenous group of clonal stem cell disorders characterized by dysplasia and cytopenia in one or more cell lineages. Anemia is a very common symptom that is often treated with blood transfusions and/or erythropoiesis stimulating factors. Iron overload results from a combination of these factors together with the disease-associated ineffective erythropoiesis, that is seen especially in MDS cases with SF3B1 mutations. A growing body of research has shown that erythroferrone is an important regulator of hepcidin, the master regulator of systemic iron homeostasis. Consequently, it is of interest to understand how this molecule contributes to regulating the iron balance in MDS patients. This short review evaluates our current understanding of erythroferrone in general, but more specifically in MDS and seeks to place in context how the current knowledge could be utilized for prognostication and therapy.
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Affiliation(s)
- Mohammed L Abba
- Department of Hematology and Oncology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Department of Hematology and Oncology, University Hospital Mannheim, Mannheim, Germany
| | - Vladimir Riabov
- Department of Hematology and Oncology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Daniel Nowak
- Department of Hematology and Oncology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Department of Hematology and Oncology, University Hospital Mannheim, Mannheim, Germany
| | - Wolf-Karsten Hofmann
- Department of Hematology and Oncology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Department of Hematology and Oncology, University Hospital Mannheim, Mannheim, Germany
| | - Tobias Boch
- Department of Hematology and Oncology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Department of Hematology and Oncology, University Hospital Mannheim, Mannheim, Germany
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3
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Sharma P, Bhatia P, Singh M, Jamwal M, Pallavelangini S, Das R, Malhotra P, Attri SV, Ducamp S, Fleming MD, Trehan A. Comprehensive Genomic Analysis Identifies a Diverse Landscape of Sideroblastic and Nonsideroblastic Iron-Related Anemias with Novel and Pathogenic Variants in an Iron-Deficient Endemic Setting. J Mol Diagn 2024; 26:430-444. [PMID: 38360212 DOI: 10.1016/j.jmoldx.2024.01.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 01/19/2024] [Accepted: 01/30/2024] [Indexed: 02/17/2024] Open
Abstract
Inherited iron metabolism defects are possibly missed or underdiagnosed in iron-deficient endemic settings because of a lack of awareness or a methodical screening approach. Hence, we systematically evaluated anemia cases (2019 to 2021) based on clinical phenotype, normal screening tests (high-performance liquid chromatography, α gene sequencing, erythrocyte sedimentation rate, C-reactive protein, and tissue transglutaminase), and abnormal iron profile by targeted next-generation sequencing (26-gene panel) supplemented with whole-exome sequencing, multiplex ligation probe amplification/mitochondrial DNA sequencing, and chromosomal microarray. Novel variants in ALAS2, STEAP3, and HSPA9 genes were functionally validated. A total of 290 anemia cases were screened, and 41 (14%) enrolled for genomic testing as per inclusion criteria. Comprehensive genomic testing revealed pathogenic variants in 23 of 41 cases (56%). Congenital sideroblastic anemia was the most common diagnosis (14/23; 61%), with pathogenic variations in ALAS2 (n = 6), SLC25A38 (n = 3), HSPA9 (n = 2) and HSCB, SLC19A2, and mitochondrial DNA deletion (n = 1 each). Nonsideroblastic iron defects included STEAP3-related microcytic anemia (2/23; 8.7%) and hypotransferrenemia (1/23; 4.3%). A total of 6 of 22 cases (27%) revealed a non-iron metabolism gene defect on whole-exome sequencing. Eleven novel variants (including variants of uncertain significance) were noted in 13 cases. Genotype-phenotype correlation revealed a significant association of frameshift/nonsense/splice variants with lower presentation age (0.8 months versus 9 years; P < 0.01) compared with missense variants. The systematic evaluation helped uncover an inherited iron defect in 41% (17/41) of cases, suggesting the need for active screening and awareness for these rare diseases in an iron-deficient endemic population.
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Affiliation(s)
- Pankaj Sharma
- Pediatric Haematology Oncology Unit, Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Prateek Bhatia
- Pediatric Haematology Oncology Unit, Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
| | - Minu Singh
- Pediatric Haematology Oncology Unit, Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Manu Jamwal
- Department of Haematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Swetha Pallavelangini
- Pediatric Haematology Oncology Unit, Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Reena Das
- Department of Haematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Pankaj Malhotra
- Department of Clinical Haematology and Medical Oncology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Savita V Attri
- Pediatric Biochemistry Laboratory, Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Sarah Ducamp
- Department of Pathology, Boston Children's Hospital, Boston, Massachusetts
| | - Mark D Fleming
- Department of Pathology, Boston Children's Hospital, Boston, Massachusetts
| | - Amita Trehan
- Pediatric Haematology Oncology Unit, Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
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Hevessy Z, Toth G, Antal-Szalmas P, Tokes-Fuzesi M, Kappelmayer J, Karai B, Ajzner E. Algorithm of differential diagnosis of anemia involving laboratory medicine specialists to advance diagnostic excellence. Clin Chem Lab Med 2024; 62:410-420. [PMID: 37823455 DOI: 10.1515/cclm-2023-0807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 10/03/2023] [Indexed: 10/13/2023]
Abstract
OBJECTIVES Anemia is a severe global public health issue. Testing practices for anemia suggest overuse of screening laboratory tests and misinterpretation of studies even in "easy-to-diagnose" underlying causes, leading to late diagnoses and missed treatment opportunities. We aimed to develop a complete and efficient algorithm for clinical pathologists and laboratory medicine physicians for the differential diagnosis of anemia. METHODS Comprehensive literature search encompassing original articles, studies, reviews, gold standard books, and other evidence. RESULTS We created a complex algorithm, primarily for clinical pathology/laboratory use, that explores all major and several rare causes of anemia in an efficient and evidence-based manner. The algorithm includes gold-standard diagnostic laboratory tests available in most clinical laboratories and indices that can be easily calculated to provide an evidence-based differential diagnosis of anemia. CONCLUSIONS The diagnostic strategy combines previously available diagnostic tests and protocols in an efficient order. Clinical pathologists following the algorithm can independently provide valuable diagnostic support for healthcare providers. Clinical pathologists providing complete differential diagnostic services with the proposed algorithm may create an opportunity for an advanced diagnostic service that supports diagnostic excellence and helps patients receive a timely diagnosis and early treatment opportunities.
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Affiliation(s)
- Zsuzsanna Hevessy
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Gabor Toth
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Peter Antal-Szalmas
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Margit Tokes-Fuzesi
- Department of Laboratory Medicine, University of Pecs, Medical School, Pecs, Hungary
| | - Janos Kappelmayer
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Bettina Karai
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Eva Ajzner
- Central Laboratory of Szabolcs-Szatmar-Bereg County Teaching Hospital, Nyiregyhaza, Hungary
- Hematology Unit of South-Pest Central Hospital and National Institute of Hematology and Infectology, Budapest, Hungary
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5
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Moura PL, Mortera-Blanco T, Hofman IJ, Todisco G, Kretzschmar WW, Björklund AC, Creignou M, Hagemann-Jensen M, Ziegenhain C, Cabrerizo Granados D, Barbosa I, Walldin G, Jansson M, Ashley N, Mead AJ, Lundin V, Dimitriou M, Yoshizato T, Woll PS, Ogawa S, Sandberg R, Jacobsen SEW, Hellström-Lindberg E. Erythroid Differentiation Enhances RNA Mis-Splicing in SF3B1-Mutant Myelodysplastic Syndromes with Ring Sideroblasts. Cancer Res 2024; 84:211-225. [PMID: 37921711 PMCID: PMC10790130 DOI: 10.1158/0008-5472.can-23-3038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 10/28/2023] [Accepted: 10/31/2023] [Indexed: 11/04/2023]
Abstract
Myelodysplastic syndromes with ring sideroblasts (MDS-RS) commonly develop from hematopoietic stem cells (HSC) bearing mutations in the splicing factor SF3B1 (SF3B1mt). Direct studies into MDS-RS pathobiology have been limited by a lack of model systems that fully recapitulate erythroid biology and RS development and the inability to isolate viable human RS. Here, we combined successful direct RS isolation from patient samples, high-throughput multiomics analysis of cells encompassing the SF3B1mt stem-erythroid continuum, and functional assays to investigate the impact of SF3B1mt on erythropoiesis and RS accumulation. The isolated RS differentiated, egressed into the blood, escaped traditional nonsense-mediated decay (NMD) mechanisms, and leveraged stress-survival pathways that hinder wild-type hematopoiesis through pathogenic GDF15 overexpression. Importantly, RS constituted a contaminant of magnetically enriched CD34+ cells, skewing bulk transcriptomic data. Mis-splicing in SF3B1mt cells was intensified by erythroid differentiation through accelerated RNA splicing and decreased NMD activity, and SF3B1mt led to truncations in several MDS-implicated genes. Finally, RNA mis-splicing induced an uncoupling of RNA and protein expression, leading to critical abnormalities in proapoptotic p53 pathway genes. Overall, this characterization of erythropoiesis in SF3B1mt RS provides a resource for studying MDS-RS and uncovers insights into the unexpectedly active biology of the "dead-end" RS. SIGNIFICANCE Ring sideroblast isolation combined with state-of-the-art multiomics identifies survival mechanisms underlying SF3B1-mutant erythropoiesis and establishes an active role for erythroid differentiation and ring sideroblasts themselves in SF3B1-mutant myelodysplastic syndrome pathogenesis.
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Affiliation(s)
- Pedro L. Moura
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Teresa Mortera-Blanco
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Isabel J. Hofman
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Gabriele Todisco
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
- Department of Biomedical Sciences, Humanitas University, Milan, Italy
| | - Warren W. Kretzschmar
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
| | - Ann-Charlotte Björklund
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Maria Creignou
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
- Department of Medicine, Division of Hematology, Karolinska University Hospital, Huddinge, Sweden
| | - Michael Hagemann-Jensen
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
- Xpress Genomics AB, Stockholm, Sweden
| | - Christoph Ziegenhain
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
- Xpress Genomics AB, Stockholm, Sweden
| | - David Cabrerizo Granados
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Indira Barbosa
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Gunilla Walldin
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Monika Jansson
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Neil Ashley
- Hematopoietic Stem Cell Laboratory, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Adam J. Mead
- Hematopoietic Stem Cell Laboratory, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Vanessa Lundin
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Marios Dimitriou
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
| | - Tetsuichi Yoshizato
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
| | - Petter S. Woll
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
| | - Seishi Ogawa
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
- Department of Pathology and Tumor Biology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
- Institute for the Advanced Study of Human Biology (WPI-ASHBi), Kyoto University, Kyoto, Japan
| | - Rickard Sandberg
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
- Xpress Genomics AB, Stockholm, Sweden
| | - Sten Eirik W. Jacobsen
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
- Department of Medicine, Division of Hematology, Karolinska University Hospital, Huddinge, Sweden
- Hematopoietic Stem Cell Laboratory, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Eva Hellström-Lindberg
- Department of Medicine Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Huddinge, Sweden
- Department of Medicine, Division of Hematology, Karolinska University Hospital, Huddinge, Sweden
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6
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Todisco G, Creignou M, Bernard E, Björklund AC, Moura PL, Tesi B, Mortera-Blanco T, Sander B, Jansson M, Walldin G, Barbosa I, Reinsbach SE, Hofman IJ, Nilsson C, Yoshizato T, Dimitriou M, Chang D, Olafsdottir S, Venckute Larsson S, Tobiasson M, Malcovati L, Woll P, Jacobsen SEW, Papaemmanuil E, Hellström-Lindberg E. Integrated Genomic and Transcriptomic Analysis Improves Disease Classification and Risk Stratification of MDS with Ring Sideroblasts. Clin Cancer Res 2023; 29:4256-4267. [PMID: 37498312 PMCID: PMC10570683 DOI: 10.1158/1078-0432.ccr-23-0538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 05/12/2023] [Accepted: 07/25/2023] [Indexed: 07/28/2023]
Abstract
PURPOSE Ring sideroblasts (RS) define the low-risk myelodysplastic neoplasm (MDS) subgroup with RS but may also reflect erythroid dysplasia in higher risk myeloid neoplasm. The benign behavior of MDS with RS (MDSRS+) is limited to SF3B1-mutated cases without additional high-risk genetic events, but one third of MDSRS+ carry no SF3B1 mutation, suggesting that different molecular mechanisms may underlie RS formation. We integrated genomic and transcriptomic analyses to evaluate whether transcriptome profiles may improve current risk stratification. EXPERIMENTAL DESIGN We studied a prospective cohort of MDSRS+ patients irrespective of World Health Organization (WHO) class with regard to somatic mutations, copy-number alterations, and bone marrow CD34+ cell transcriptomes to assess whether transcriptome profiles add to prognostication and provide input on disease classification. RESULTS SF3B1, SRSF2, or TP53 multihit mutations were found in 89% of MDSRS+ cases, and each mutation category was associated with distinct clinical outcome, gene expression, and alternative splicing profiles. Unsupervised clustering analysis identified three clusters with distinct hemopoietic stem and progenitor (HSPC) composition, which only partially overlapped with mutation groups. IPSS-M and the transcriptome-defined proportion of megakaryocyte/erythroid progenitors (MEP) independently predicted survival in multivariable analysis. CONCLUSIONS These results provide essential input on the molecular basis of SF3B1-unmutated MDSRS+ and propose HSPC quantification as a prognostic marker in myeloid neoplasms with RS.
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Affiliation(s)
- Gabriele Todisco
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Unit of Precision Hematology Oncology, IRCCS S. Matteo Hospital Foundation, Pavia, Italy
| | - Maria Creignou
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
- Phase I Unit, Center for Clinical Cancer Studies, Karolinska University Hospital, Stockholm, Sweden
| | - Elsa Bernard
- Computational Oncology Service, Department of Epidemiology & Biostatistics and Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Ann-Charlotte Björklund
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Pedro Luis Moura
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Bianca Tesi
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Clinical Genetics, Karolinska University Laboratory, Karolinska University Hospital, Stockholm, Sweden
| | - Teresa Mortera-Blanco
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Birgitta Sander
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
| | - Monika Jansson
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
- Medical Unit Hematology, Karolinska University Hospital, Stockholm, Sweden
| | - Gunilla Walldin
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
- Medical Unit Hematology, Karolinska University Hospital, Stockholm, Sweden
| | - Indira Barbosa
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Susanne E. Reinsbach
- Department of Biology and Biological Engineering, National Bioinformatics Infrastructure Sweden, Science for Life Laboratory, Chalmers University of Technology, Gothenburg, Sweden
| | - Isabel Juliana Hofman
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Christer Nilsson
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
- Medical Unit Hematology, Karolinska University Hospital, Stockholm, Sweden
| | - Tetsuichi Yoshizato
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Marios Dimitriou
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - David Chang
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Svannildur Olafsdottir
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Sigita Venckute Larsson
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Magnus Tobiasson
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
- Medical Unit Hematology, Karolinska University Hospital, Stockholm, Sweden
| | - Luca Malcovati
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Unit of Precision Hematology Oncology, IRCCS S. Matteo Hospital Foundation, Pavia, Italy
| | - Petter Woll
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Sten Eirik W. Jacobsen
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Elli Papaemmanuil
- Computational Oncology Service, Department of Epidemiology & Biostatistics and Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Eva Hellström-Lindberg
- Department of Medicine, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
- Medical Unit Hematology, Karolinska University Hospital, Stockholm, Sweden
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7
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Mian SA, Philippe C, Maniati E, Protopapa P, Bergot T, Piganeau M, Nemkov T, Bella DD, Morales V, Finch AJ, D’Alessandro A, Bianchi K, Wang J, Gallipoli P, Kordasti S, Kubasch AS, Cross M, Platzbecker U, Wiseman DH, Bonnet D, Bernard DG, Gribben JG, Rouault-Pierre K. Vitamin B5 and succinyl-CoA improve ineffective erythropoiesis in SF3B1-mutated myelodysplasia. Sci Transl Med 2023; 15:eabn5135. [PMID: 36857430 PMCID: PMC7614516 DOI: 10.1126/scitranslmed.abn5135] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 02/08/2023] [Indexed: 03/03/2023]
Abstract
Patients with myelodysplastic syndrome and ring sideroblasts (MDS-RS) present with symptomatic anemia due to ineffective erythropoiesis that impedes their quality of life and increases morbidity. More than 80% of patients with MDS-RS harbor splicing factor 3B subunit 1 (SF3B1) mutations, the founder aberration driving MDS-RS disease. Here, we report how mis-splicing of coenzyme A synthase (COASY), induced by mutations in SF3B1, affects heme biosynthesis and erythropoiesis. Our data revealed that COASY was up-regulated during normal erythroid differentiation, and its silencing prevented the formation of erythroid colonies, impeded erythroid differentiation, and precluded heme accumulation. In patients with MDS-RS, loss of protein due to COASY mis-splicing led to depletion of both CoA and succinyl-CoA. Supplementation with COASY substrate (vitamin B5) rescued CoA and succinyl-CoA concentrations in SF3B1mut cells and mended erythropoiesis differentiation defects in MDS-RS primary patient cells. Our findings reveal a key role of the COASY pathway in erythroid maturation and identify upstream and downstream metabolites of COASY as a potential treatment for anemia in patients with MDS-RS.
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Affiliation(s)
- Syed A Mian
- The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Céline Philippe
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Eleni Maniati
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Pantelitsa Protopapa
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Tiffany Bergot
- University of Brest, Inserm, EFS, UMR1078, GGB, 29238 Brest, France
| | | | - Travis Nemkov
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver - Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Doriana Di Bella
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Valle Morales
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Andrew J Finch
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Angelo D’Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver - Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Katiuscia Bianchi
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Jun Wang
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Paolo Gallipoli
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Shahram Kordasti
- System Cancer Immunology, Comprehensive Cancer Centre, King's College London, London WC2R 2LS, United Kingdom
| | - Anne Sophie Kubasch
- Department of Hematology, Cellular Therapy and Hemostaseology, Leipzig University Hospital, 04103 Leipzig, Germany
| | - Michael Cross
- Department of Hematology, Cellular Therapy and Hemostaseology, Leipzig University Hospital, 04103 Leipzig, Germany
| | - Uwe Platzbecker
- Department of Hematology, Cellular Therapy and Hemostaseology, Leipzig University Hospital, 04103 Leipzig, Germany
| | - Daniel H Wiseman
- Division of Cancer Sciences, The University of Manchester, Manchester M20 4GJ, UK
| | | | - Delphine G Bernard
- University of Brest, Inserm, EFS, UMR1078, GGB, 29238 Brest, France
- Centre de Ressources Biologiques du CHRU de Brest, 29238 Brest, France
| | - John G Gribben
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Kevin Rouault-Pierre
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, United Kingdom
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8
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Alam MM, Alathaibi A, Attar RA, Kashif M, Al-Ghamdi HS, Alharthi SA, Bokhary A, Althomali M. Pyridoxine Refractory Sideroblastic Anemia: Diagnosis and Misdiagnosis. CLINICAL PEDIATRIC HEMATOLOGY-ONCOLOGY 2022. [DOI: 10.15264/cpho.2022.29.2.65] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
| | - Abdulrhman Alathaibi
- Department of Hematology/Oncology, Alhada Armed Forces Hospital, Taif, Saudi Arabia
| | - Ruwayd Adel Attar
- Department of Hematology/Oncology, Alhada Armed Forces Hospital, Taif, Saudi Arabia
| | - Muhammad Kashif
- Department of Laboratory, Alhada Armed Forces Hospital, Taif, Saudi Arabia
| | | | | | | | - Muteb Althomali
- Department of Hematology/Oncology, Alhada Armed Forces Hospital, Taif, Saudi Arabia
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Girard S, Genevieve F, Rault E, Fenneteau O, Lesesve JF. When Ring Sideroblasts on Bone Marrow Smears Are Inconsistent with the Diagnosis of Myelodysplastic Neoplasms. Diagnostics (Basel) 2022; 12:1752. [PMID: 35885655 PMCID: PMC9320983 DOI: 10.3390/diagnostics12071752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/08/2022] [Accepted: 07/16/2022] [Indexed: 01/19/2023] Open
Abstract
Ring sideroblasts are commonly seen in myelodysplastic neoplasms and are a key condition for identifying distinct entities of myelodysplastic neoplasms according to the WHO classification. However, the presence of ring sideroblasts is not exclusive to myelodysplastic neoplasms. Ring sideroblasts are as well either encountered in non-clonal secondary acquired disorders, such as exposure to toxic substances, drug/medicine, copper deficiency, zinc overload, lead poison, or hereditary sideroblastic anemias related to X-linked, autosomal, or mitochondrial mutations. This review article will discuss diseases associated with ring sideroblasts outside the context of myelodysplastic neoplasms. Knowledge of the differential diagnoses characterized by the presence of ring sideroblasts in bone marrow is essential to prevent any misdiagnosis, which leads to delayed diagnosis and subsequent management of patients that differ in the different forms of sideroblastic anemia.
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Affiliation(s)
- Sandrine Girard
- Laboratory of Hematology, Center of Biology and Pathology East, Hospices Civils de Lyon, 69500 Bron, France
- French-Speaking Cellular Hematology Group, 69500 Bron, France; (F.G.); (E.R.); (O.F.); (J.-F.L.)
| | - Franck Genevieve
- French-Speaking Cellular Hematology Group, 69500 Bron, France; (F.G.); (E.R.); (O.F.); (J.-F.L.)
- Laboratory of Hematology, Angers University Hospital, 49100 Angers, France
| | - Emmanuelle Rault
- French-Speaking Cellular Hematology Group, 69500 Bron, France; (F.G.); (E.R.); (O.F.); (J.-F.L.)
- Department of Biological Hematology, Tours University Hospital, 37081 Tours, France
| | - Odile Fenneteau
- French-Speaking Cellular Hematology Group, 69500 Bron, France; (F.G.); (E.R.); (O.F.); (J.-F.L.)
- Laboratory of Hematology, Robert Debré Hospital, APHP, 75019 Paris, France
| | - Jean-François Lesesve
- French-Speaking Cellular Hematology Group, 69500 Bron, France; (F.G.); (E.R.); (O.F.); (J.-F.L.)
- Laboratory of Hematology, Nancy University Hospital, 54000 Nancy, France
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10
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Baba Y, Sakai H, Kabasawa N, Harada H. Successful Treatment of Immune Thrombocytopenic Purpura with Intracranial Hemorrhaging and Duodenal Bleeding Following SARS-CoV-2 Vaccination. Intern Med 2022; 61:1891-1895. [PMID: 35400701 PMCID: PMC9259817 DOI: 10.2169/internalmedicine.9199-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Several vaccines have been developed for coronavirus disease 2019 - caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) - in record time. A few cases of immune thrombocytopenic purpura (ITP) following SARS-CoV-2 vaccination have been reported. We herein report a 90-year-old man who received the Pfizer-BioNTech SARS-CoV-2 vaccine (BNT162b2) and developed severe thrombocytopenia with intracranial hemorrhaging and duodenal bleeding, consistent with vaccine-related ITP. He was successfully treated with intravenous immunoglobulin, prednisolone, and eltrombopag and discharged without cytopenia. Vaccine-related ITP should be suspected in patients presenting with abnormal bleeding or purpura after vaccination.
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Affiliation(s)
- Yuta Baba
- Division of Hematology, Department of Medicine, Showa University Fujigaoka Hospital, Japan
| | - Hirotaka Sakai
- Division of Hematology, Department of Medicine, Showa University Fujigaoka Hospital, Japan
| | - Nobuyuki Kabasawa
- Division of Hematology, Department of Medicine, Showa University Fujigaoka Hospital, Japan
| | - Hiroshi Harada
- Division of Hematology, Department of Medicine, Showa University Fujigaoka Hospital, Japan
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11
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Nathan DI, Feld J, El Jamal SM, Mascarenhas J, Tremblay D. Myelodysplastic syndrome/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis: Ringing in a new future. Leuk Res 2022; 115:106820. [DOI: 10.1016/j.leukres.2022.106820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 01/19/2023]
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12
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Petiti J, Itri F, Signorino E, Frolli A, Fava C, Armenio M, Marini S, Giugliano E, Lo Iacono M, Saglio G, Cilloni D. Detection of SF3B1 p.Lys700Glu Mutation by PNA-PCR Clamping in Myelodysplastic Syndromes and Myeloproliferative Neoplasms. J Clin Med 2022; 11:jcm11051267. [PMID: 35268357 PMCID: PMC8911290 DOI: 10.3390/jcm11051267] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/08/2022] [Accepted: 02/23/2022] [Indexed: 01/25/2023] Open
Abstract
Mutations in SF3B1 are found in 20% of myelodysplastic syndromes and 5–10% of myeloproliferative neoplasms, where they are considered important for diagnosis and therapy decisions. Sanger sequencing and NGS are the currently available methods to identify SF3B1 mutations, but both are time-consuming and expensive techniques that are not practicable in most small-/medium-sized laboratories. To identify the most frequent SF3B1 mutation, p.Lys700Glu, we developed a novel fast and cheap assay based on PNA-PCR clamping. After setting the optimal PCR conditions, the limit of detection of PNA-PCR clamping was evaluated, and the method allowed up to 0.1% of mutated SF3B1 to be identified. Successively, PNA-PCR clamping and Sanger sequencing were used to blind test 90 DNA from patients affected by myelodysplastic syndromes and myeloproliferative neoplasms for the SF3B1 p.Lys700Glu mutation. PNA-PCR clamping and Sanger sequencing congruently identified 75 negative and 13 positive patients. Two patients identified as positive by PNA-PCR clamping were missed by Sanger analysis. The discordant samples were analyzed by NGS, which confirmed the PNA-PCR clamping result, indicating that these samples contained the SF3B1 p.Lys700Glu mutation. This approach could easily increase the characterization of myelodysplastic syndromes and myeloproliferative neoplasms in small-/medium-sized laboratories, and guide patients towards more appropriate therapy.
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Affiliation(s)
- Jessica Petiti
- Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (F.I.); (E.S.); (A.F.); (C.F.); (G.S.); (D.C.)
- Correspondence: (J.P.); (M.L.I.); Tel.: +39-011-670-5480 (J.P.); +39-011-670-5489 (M.L.I.)
| | - Federico Itri
- Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (F.I.); (E.S.); (A.F.); (C.F.); (G.S.); (D.C.)
| | - Elisabetta Signorino
- Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (F.I.); (E.S.); (A.F.); (C.F.); (G.S.); (D.C.)
| | - Antonio Frolli
- Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (F.I.); (E.S.); (A.F.); (C.F.); (G.S.); (D.C.)
| | - Carmen Fava
- Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (F.I.); (E.S.); (A.F.); (C.F.); (G.S.); (D.C.)
| | - Marco Armenio
- Department of Molecular Biotechnology and Health Sciences, University of Turin, 10126 Turin, Italy;
| | - Silvia Marini
- Division of Internal Medicine and Hematology, San Luigi Gonzaga Hospital, 10043 Orbassano, Italy; (S.M.); (E.G.)
| | - Emilia Giugliano
- Division of Internal Medicine and Hematology, San Luigi Gonzaga Hospital, 10043 Orbassano, Italy; (S.M.); (E.G.)
| | - Marco Lo Iacono
- Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (F.I.); (E.S.); (A.F.); (C.F.); (G.S.); (D.C.)
- Correspondence: (J.P.); (M.L.I.); Tel.: +39-011-670-5480 (J.P.); +39-011-670-5489 (M.L.I.)
| | - Giuseppe Saglio
- Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (F.I.); (E.S.); (A.F.); (C.F.); (G.S.); (D.C.)
| | - Daniela Cilloni
- Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (F.I.); (E.S.); (A.F.); (C.F.); (G.S.); (D.C.)
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Vobugari N, Chaturvedi M, Schlam-Camhi IM, Smith HP. Sideroblastic anaemia in a patient with sickle cell disease. BMJ Case Rep 2022; 15:15/2/e246623. [PMID: 35135795 PMCID: PMC8830102 DOI: 10.1136/bcr-2021-246623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Sideroblastic anaemia is a rare condition. We report a unique case of concomitant sideroblastic anaemia in a patient with sickle cell disease with long-standing blood transfusion history. Due to a low prevalence of sideroblastic anaemia, the diagnosis of sideroblastic anaemia is often difficult, especially when coexisting with common types of anaemia, including sickle cell disease. This case highlights the detrimental effects of anchoring bias. Rare causes of refractory anaemia should be considered in patients with haemoglobin disorders as the therapeutic approaches for these conditions are different. High suspicion on the part of the clinician and low threshold for workup of anaemia often aids in the diagnosis of coexisting conditions such as sideroblastic anaemia. Early diagnosis and treatment of sideroblastic anaemia improves patient outcomes and prevents long-term complications.
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Affiliation(s)
- Nikitha Vobugari
- Internal Medicine, MedStar Washington Hospital Center, Washington, DC, USA
| | - Mansi Chaturvedi
- Internal Medicine, MedStar Washington Hospital Center, Washington, DC, USA
| | - Ilana Miriam Schlam-Camhi
- Hematology/Oncology, Tufts Medical Center, Boston, Massachusetts, USA
- Hematology/Oncology, MedStar Washington Hospital Center, Washington, DC, USA
| | - Hedy Patricia Smith
- Hematology/Oncology, MedStar Washington Hospital Center, Washington, DC, USA
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14
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Beecher G, Fleming MD, Liewluck T. Hereditary myopathies associated with hematological abnormalities. Muscle Nerve 2022; 65:374-390. [PMID: 34985130 DOI: 10.1002/mus.27474] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 12/10/2021] [Accepted: 12/11/2021] [Indexed: 01/19/2023]
Abstract
The diagnostic evaluation of a patient with suspected hereditary muscle disease can be challenging. Clinicians rely largely on clinical history and examination features, with additional serological, electrodiagnostic, radiologic, histopathologic, and genetic investigations assisting in definitive diagnosis. Hematological testing is inexpensive and widely available, but frequently overlooked in the hereditary myopathy evaluation. Hematological abnormalities are infrequently encountered in this setting; however, their presence provides a valuable clue, helps refine the differential diagnosis, tailors further investigation, and assists interpretation of variants of uncertain significance. A diverse spectrum of hematological abnormalities is associated with hereditary myopathies, including anemias, leukocyte abnormalities, and thrombocytopenia. Recurrent rhabdomyolysis in certain glycolytic enzymopathies co-occurs with hemolytic anemia, often chronic and mild in phosphofructokinase and phosphoglycerate kinase deficiencies, or acute and fever-associated in aldolase-A and triosephosphate isomerase deficiency. Sideroblastic anemia, commonly severe, accompanies congenital-to-childhood onset mitochondrial myopathies including Pearson marrow-pancreas syndrome and mitochondrial myopathy, lactic acidosis, and sideroblastic anemia phenotypes. Congenital megaloblastic macrocytic anemia and mitochondrial dysfunction characterize SFXN4-related myopathy. Neutropenia, chronic or cyclical, with recurrent infections, infantile-to-childhood onset skeletal myopathy and cardiomyopathy are typical of Barth syndrome, while chronic neutropenia without infection occurs rarely in DNM2-centronuclear myopathy. Peripheral eosinophilia may accompany eosinophilic inflammation in recessive calpainopathy. Lipid accumulation in leukocytes on peripheral blood smear (Jordans' anomaly) is pathognomonic for neutral lipid storage diseases. Mild thrombocytopenia occurs in autosomal dominant, childhood-onset STIM1 tubular aggregate myopathy, STIM1 and ORAI1 deficiency syndromes, and GNE myopathy. Herein, we review these hereditary myopathies in which hematological features play a prominent role.
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Affiliation(s)
- Grayson Beecher
- Division of Neuromuscular Medicine, Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA
| | - Mark D Fleming
- Department of Pathology, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Teerin Liewluck
- Division of Neuromuscular Medicine, Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA
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15
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Ineffective erythropoiesis and its treatment. Blood 2021; 139:2460-2470. [PMID: 34932791 DOI: 10.1182/blood.2021011045] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 11/29/2021] [Accepted: 11/29/2021] [Indexed: 01/19/2023] Open
Abstract
The erythroid marrow and circulating red blood cells (RBCs) are the key components of the human erythron. Abnormalities of the erythron that are responsible for anemia can be distinguished into 3 major categories, that is, erythroid hypoproliferation, ineffective erythropoiesis, and peripheral hemolysis. Ineffective erythropoiesis is characterized by erythropoietin-driven expansion of early-stage erythroid precursors, associated with apoptosis of late-stage precursors. This mechanism is primarily responsible for anemia in inherited disorders like β-thalassemia, inherited sideroblastic anemias, and congenital dyserythropoietic anemias, as well as in acquired conditions like some subtypes of myelodysplastic syndromes (MDS). The inherited anemias due to ineffective erythropoiesis are also defined as iron loading anemias because of the associated parenchymal iron loading caused by the release of erythroid factors that suppress hepcidin production. Novel treatments specifically targeting ineffective erythropoiesis are being developed. Iron restriction through enhancement of hepcidin activity or inhibition of ferroportin function has been shown to reduce ineffective erythropoiesis in murine models of β-thalassemia. Luspatercept is a TGF-β ligand trap that inhibits SMAD2/3 signaling. Based on pre-clinical and clinical studies, this compound is now approved for the treatment of anemia in adult patients with β-thalassemia who require regular RBC transfusions. Luspatercept is also approved for the treatment of transfusion-dependent anemia in patients with MDS with ring sideroblasts, most of whom carry a somatic SF3B1mutation. While long-term efficacy and safety of luspatercept need to be evaluated both in β-thalassemia and MDS, defining the molecular mechanisms of ineffective erythropoiesis in different disorders might allow the discovery of new effective compounds.
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16
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Kanagal-Shamanna R, Montalban-Bravo G, Sasaki K, Darbaniyan F, Jabbour E, Bueso-Ramos C, Wei Y, Chien K, Kadia T, Ravandi F, Borthakur G, Soltysiak KA, Routbort M, Patel K, Pierce S, Medeiros LJ, Kantarjian HM, Garcia-Manero G. Only SF3B1 mutation involving K700E independently predicts overall survival in myelodysplastic syndromes. Cancer 2021; 127:3552-3565. [PMID: 34161603 PMCID: PMC10015977 DOI: 10.1002/cncr.33745] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/14/2021] [Accepted: 05/11/2021] [Indexed: 11/08/2022]
Abstract
BACKGROUND SF3B1 mutations (SF3B1mut ) in myelodysplastic syndromes (MDS) frequently involve codon K700E and have a favorable prognosis. The prognostic effect of non-K700E SF3B1mut is uncertain. METHODS The authors analyzed the clinicopathological features and outcomes of a single-institution series of 94 treatment-naive SF3B1mut MDS patients (18%) and 415 treatment-naive SF3B1wt MDS patients and explored the differences between K700E and non-K700E SF3B1mut MDS. RESULTS Fifty-five patients (59%) carried K700E. Recurrent non-K700E mutations (39 [41%]) included R625, H662, and K666. Compared with SF3B1mut K700E patients, non-K700E patients had a lower median absolute neutrophil count (1.8 vs 2.4; P = .005) and were frequently "high" according to the Revised International Prognostic Scoring System (19% vs 4%; P = .031). Non-K700E MDS was associated frequently with RUNX1 (26% vs 7%; P = .012) and exclusively with BCOR, IDH2, and SRSF2 mutations. A splicing analysis showed the differential distribution of alternatively spliced events and gene expression profiles between K700 and non-K700E MDS patients. The majority (at least 80%) of SF3B1mut K700E, SF3B1mut non-K700E, and SF3B1wt patients were treated with hypomethylating agents. Over a median follow-up of 16 months, SF3B1mut had superior overall survival (OS) in comparison with SF3B1wt in all MDS patients (not reached vs 25.2 months; P = .0003), in patients with low-grade MDS, and in patients with myelodysplastic syndromes with ring sideroblasts (MDS-RS). Compared with SF3B1wt , SF3B1mut K700E had superior outcomes in all MDS (median OS, 25 months vs not reached; P = .0001), in low-grade MDS (median OS, 41.3 months vs not reached; P = .0015), and in MDS-RS (median OS, 22.3 months vs not reached; P = .0001), but no significant difference was seen between non-K700E and SF3B1wt MDS. By multivariable analysis, the absence of SF3B1mut K700E mutations was independently associated with the prognosis. CONCLUSIONS This study highlights the importance of the SF3B1 mutation subtype in MDS risk assessment. LAY SUMMARY Myelodysplastic syndromes (MDS) with SF3B1 mutations are regarded as having a favorable prognosis by both the World Health Organization and the International Working Group for the Prognosis of Myelodysplastic Syndromes. However, this article shows that only MDS patients with SF3B1 K700E mutations have a favorable prognosis (and not MDS patients with SF3B1 mutations involving other codons). This has important implications for refining future MDS subclassification and risk assessment criteria.
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Affiliation(s)
- Rashmi Kanagal-Shamanna
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | | | - Koji Sasaki
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Faezeh Darbaniyan
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Elias Jabbour
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Carlos Bueso-Ramos
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Yue Wei
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Kelly Chien
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Tapan Kadia
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Farhad Ravandi
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Gautam Borthakur
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Kelly A Soltysiak
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Mark Routbort
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Keyur Patel
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Sherry Pierce
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - L Jeffrey Medeiros
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Hagop M Kantarjian
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
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17
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EnvIRONmental Aspects in Myelodysplastic Syndrome. Int J Mol Sci 2021; 22:ijms22105202. [PMID: 34068996 PMCID: PMC8156755 DOI: 10.3390/ijms22105202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/06/2021] [Accepted: 05/11/2021] [Indexed: 11/24/2022] Open
Abstract
Systemic iron overload is multifactorial in patients suffering from myelodysplastic syndrome (MDS). Disease-immanent ineffective erythropoiesis together with chronic red blood cell transfusion represent the main underlying reasons. However, like the genetic heterogeneity of MDS, iron homeostasis is also diverse in different MDS subtypes and can no longer be generalized. While a certain amount of iron and reactive oxygen species (ROS) are indispensable for proper hematological output, both are harmful if present in excess. Consequently, iron overload has been increasingly recognized as an important player in MDS, which is worth paying attention to. This review focuses on iron- and ROS-mediated effects in the bone marrow niche, their implications for hematopoiesis and their yet unclear involvement in clonal evolution. Moreover, we provide recent insights into hepcidin regulation in MDS and its interaction between erythropoiesis and inflammation. Based on Tet methylcytosine dioxygenase 2 (TET2), representing one of the most frequently mutated genes in MDS, leading to disturbances in both iron homeostasis and hematopoiesis, we highlight that different genetic alteration may have different implications and that a comprehensive workup is needed for a complete understanding and development of future therapies.
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18
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Ravindra N, Athiyarath R, S E, S S, Kulkarni U, N A F, Korula A, Shaji RV, George B, Edison ES. Novel frameshift variant (c.409dupG) in SLC25A38 is a common cause of congenital sideroblastic anaemia in the Indian subcontinent. J Clin Pathol 2020; 74:157-162. [PMID: 32605921 DOI: 10.1136/jclinpath-2020-206647] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 01/19/2023]
Abstract
AIMS Congenital sideroblastic anaemias (CSAs) are a group of rare disorders with the presence of ring sideroblasts in the bone marrow. Pathogenic variants are inherited in an autosomal recessive/X-linked fashion. The study was aimed at characterising the spectrum of mutations in SLC25A38 and ALAS2 genes in sideroblastic anaemia patients, exploring the genotype-phenotype correlation and identifying the haplotype associated with any recurrent mutation. PATIENTS AND METHODS Twenty probable CSA patients were retrospectively analysed for genetic variants in ALAS2 and SLC25A38 genes by direct bidirectional sequencing. Real-time PCR was used to quantify gene expression in a case with promoter region variant in ALAS2. Three single nucleotide polymorphisms were used to establish the haplotype associated with a recurrent variant in the SLC25A38 gene. RESULTS Six patients had causative variants in ALAS2 (30%) and 11 had variants in SLC25A38 (55%). The ALAS2 mutated cases presented at a significantly later age than the SLC25A38 cases. A frameshift variant in SLC25A38 (c.409dupG) was identified in six unrelated patients and was a common variant in our population exhibiting 'founder effect'. CONCLUSION This is the largest series of sideroblastic anaemia cases with molecular characterisation from the Indian subcontinent.
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Affiliation(s)
- Niveditha Ravindra
- Department of Haematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Rekha Athiyarath
- Department of Haematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Eswari S
- Department of Haematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Sumithra S
- Department of Haematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Uday Kulkarni
- Department of Haematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Fouzia N A
- Department of Haematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Anu Korula
- Department of Haematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Ramachandran V Shaji
- Department of Haematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Biju George
- Department of Haematology, Christian Medical College, Vellore, Tamil Nadu, India
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19
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Mangla G, Garg N, Bansal D, Kotru M, Sikka M. Peripheral Blood and Bone Marrow Findings in Chronic Alcoholics with Special Reference to Acquired Sideroblastic Anemia. Indian J Hematol Blood Transfus 2019; 36:559-564. [PMID: 32647433 DOI: 10.1007/s12288-019-01188-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 09/13/2019] [Indexed: 11/28/2022] Open
Abstract
Anemia associated with alcoholism has numerous causes, most common being megaloblastic anemia and acquired sideroblastic anemia (SA). The bone marrow aspirate (BMA) and bone marrow iron (BMIr) findings and their correlation with peripheral blood smear (PBS) have not been extensively described in literature. We aim to study the spectrum of hematological abnormalities in chronic alcoholics. Complete blood count (CBC), PBS, BMA and BMIr of 71 chronic alcoholics were studied retrospectively over a period of 3 years. The slides were reviewed by 2 pathologists. The clinical history, CBC, PBS, BMA and BMIr findings were recorded. Out of 71 patients, 68 (95.77%) had anaemia. Red cell morphology varied from normocytic-normochromic, microcytic-hypochromic, macrocytic, to dimorphic anaemia. Principal findings seen on BMA were erythroid hyperplasia and megaloblastic maturation. BMIr was available in 41 patients; iron stores were decreased in 2 (4.88%), normal in 14 (34.15%), increased in 25 (60.97%). Seven (17.07%) cases showed presence of ring sideroblasts. Chronic alcoholics show a variety of abnormalities in BMA, which closely mimic many haematological disorders. A history of alcoholism should always be taken in these circumstances. SA should be ruled out in all chronic alcoholics with anaemia not responding to vitamin B12/folic acid, even with macrocytic picture on PBS.
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Affiliation(s)
- Gunjan Mangla
- Department of Pathology, University College of Medical Sciences and Guru Teg Bahadur Hospital, Dilshad Garden, New Delhi, 110095 Delhi India
| | - Neha Garg
- Department of Pathology, University College of Medical Sciences and Guru Teg Bahadur Hospital, Dilshad Garden, New Delhi, 110095 Delhi India
| | - Divya Bansal
- Department of Pathology, University College of Medical Sciences and Guru Teg Bahadur Hospital, Dilshad Garden, New Delhi, 110095 Delhi India
| | - Mrinalini Kotru
- Department of Pathology, University College of Medical Sciences and Guru Teg Bahadur Hospital, Dilshad Garden, New Delhi, 110095 Delhi India
| | - Meera Sikka
- Department of Pathology, University College of Medical Sciences and Guru Teg Bahadur Hospital, Dilshad Garden, New Delhi, 110095 Delhi India
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20
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Allain JS, Belhomme N, Henriot B, Haas M, Le Gall-Godard M, Pastoret C, Jego P. [A microcytic sideroblastic anemia successfully treated with B6 vitamin]. Rev Med Interne 2019; 40:462-465. [PMID: 31133329 DOI: 10.1016/j.revmed.2019.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 04/12/2019] [Accepted: 05/08/2019] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Sideroblastic anemia is a rare cause of microcytic anemia, which is characterized by ring sideroblasts on bone marrow aspirate. This anemia can be congenital or acquired. CASE REPORT We report the case of an alcoholic 49-year-old man who presented with a severe microcytic sideroblastic anemia related to pyridoxine (B6 vitamin) deficiency. Acid folic deficiency was associated. The blood count normalized within one month after vitamin supplementation. CONCLUSION Pyridoxine deficiency must be sought in sideroblastic anemia in patients at risk.
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Affiliation(s)
- J-S Allain
- Service de médecine interne et immunologie clinique, université de Rennes 1, CHU de Rennes, 35000 Rennes, France; Pôle médecine, cardiovasculaire et métabolisme, centre hospitalier de Saint-Malo, 35400 Saint-Malo, France.
| | - N Belhomme
- Service de médecine interne et immunologie clinique, université de Rennes 1, CHU de Rennes, 35000 Rennes, France
| | - B Henriot
- Service de médecine interne et immunologie clinique, université de Rennes 1, CHU de Rennes, 35000 Rennes, France; Service de médecine interne et immunologie clinique, centre hospitalier René-Pleven, CHU de Rennes, 22100 Dinan, France
| | - M Haas
- Laboratoire d'hématologie, université de Rennes 1, CHU de Rennes, 35000 Rennes, France
| | - M Le Gall-Godard
- Laboratoire d'hématologie, université de Rennes 1, CHU de Rennes, 35000 Rennes, France
| | - C Pastoret
- Laboratoire d'hématologie, Inserm, UMR U1236, université de Rennes 1, CHU de Rennes, 35000 Rennes, France
| | - P Jego
- Service de médecine interne et immunologie clinique, université de Rennes 1, CHU de Rennes, 35000 Rennes, France
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21
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Gheorghe GS, Hodorogea AS, Gheorghe ACD, Zaharia OIR, Neacsu O, Nanea IT, Ciobanu A. Particular etiology in a case of peripheral tetraparesis. Clin Case Rep 2019; 7:1062-1066. [PMID: 31110746 PMCID: PMC6510001 DOI: 10.1002/ccr3.2157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 03/15/2019] [Accepted: 03/27/2019] [Indexed: 11/12/2022] Open
Abstract
Lead intoxication is a rare but potentially fatal disease without appropriate intervention. The diagnosis is often difficult because of various organs involvement. We report the case of nonprofessional lead intoxication manifested by tetraparesis, severe anemia, and hemolysis in a patient having also unknown beta thalassemia minor.
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Affiliation(s)
| | | | | | | | - Ovidiu Neacsu
- University of Medicine and Pharmacy Carol DavilaBucharestRomania
| | | | - Ana Ciobanu
- University of Medicine and Pharmacy Carol DavilaBucharestRomania
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22
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Abstract
Mitochondria are an iconic distinguishing feature of eukaryotic cells. Mitochondria encompass an active organellar network that fuses, divides, and directs a myriad of vital biological functions, including energy metabolism, cell death regulation, and innate immune signaling in different tissues. Another crucial and often underappreciated function of these dynamic organelles is their central role in the metabolism of the most abundant and biologically versatile transition metals in mammalian cells, iron. In recent years, cellular and animal models of mitochondrial iron dysfunction have provided vital information in identifying new proteins that have elucidated the pathways involved in mitochondrial homeostasis and iron metabolism. Specific signatures of mitochondrial iron dysregulation that are associated with disease pathogenesis and/or progression are becoming increasingly important. Understanding the molecular mechanisms regulating mitochondrial iron pathways will help better define the role of this important metal in mitochondrial function and in human health and disease.
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Affiliation(s)
- Diane M Ward
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA
| | - Suzanne M Cloonan
- Division of Pulmonary and Critical Care Medicine, Weill Cornell Medicine, New York, NY 10065, USA;
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23
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Novel mutations in mitochondrial carrier family gene SLC25A38, causing congenital sideroblastic anemia in Iranian families, identified by whole exome sequencing. Blood Cells Mol Dis 2018; 71:39-44. [DOI: 10.1016/j.bcmd.2018.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 02/21/2018] [Accepted: 02/21/2018] [Indexed: 11/20/2022]
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24
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Agrawal S, Fox J, Thyagarajan B, Fox JH. Brain mitochondrial iron accumulates in Huntington's disease, mediates mitochondrial dysfunction, and can be removed pharmacologically. Free Radic Biol Med 2018; 120:317-329. [PMID: 29625173 PMCID: PMC5940499 DOI: 10.1016/j.freeradbiomed.2018.04.002] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/01/2018] [Accepted: 04/02/2018] [Indexed: 01/18/2023]
Abstract
Mitochondrial bioenergetic dysfunction is involved in neurodegeneration in Huntington's disease (HD). Iron is critical for normal mitochondrial bioenergetics but can also contribute to pathogenic oxidation. The accumulation of iron in the brain occurs in mouse models and in human HD. Yet the role of mitochondria-related iron dysregulation as a contributor to bioenergetic pathophysiology in HD is unclear. We demonstrate here that human HD and mouse model HD (12-week R6/2 and 12-month YAC128) brains accumulated mitochondrial iron and showed increased expression of iron uptake protein mitoferrin 2 and decreased iron-sulfur cluster synthesis protein frataxin. Mitochondria-enriched fractions from mouse HD brains had deficits in membrane potential and oxygen uptake and increased lipid peroxidation. In addition, the membrane-permeable iron-selective chelator deferiprone (1 μM) rescued these effects ex-vivo, whereas hydrophilic iron and copper chelators did not. A 10-day oral deferiprone treatment in 9-week R6/2 HD mice indicated that deferiprone removed mitochondrial iron, restored mitochondrial potentials, decreased lipid peroxidation, and improved motor endurance. Neonatal iron supplementation potentiates neurodegeneration in mouse models of HD by unknown mechanisms. We found that neonatal iron supplementation increased brain mitochondrial iron accumulation and potentiated markers of mitochondrial dysfunction in HD mice. Therefore, bi-directional manipulation of mitochondrial iron can potentiate and protect against markers of mouse HD. Our findings thus demonstrate the significance of iron as a mediator of mitochondrial dysfunction and injury in mouse models of human HD and suggest that targeting the iron-mitochondrial pathway may be protective.
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Affiliation(s)
- Sonal Agrawal
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY 82070, United States
| | - Julia Fox
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY 82070, United States
| | | | - Jonathan H Fox
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY 82070, United States.
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25
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Yu HJ, Lee YJ, Shim JW, Kim DS, Shim JY, Park MS, Woo HY, Park H, Jung HL, Kwon MJ. Mutation Analysis of X-linked Sideroblastic Anemia in a 12-Month-Old Boy by Massively Parallel Sequencing. Ann Lab Med 2018; 38:389-392. [PMID: 29611395 PMCID: PMC5895874 DOI: 10.3343/alm.2018.38.4.389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 10/26/2017] [Accepted: 02/20/2018] [Indexed: 11/19/2022] Open
Affiliation(s)
- Hui Jin Yu
- Department of Laboratory Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Young Ju Lee
- Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jae Won Shim
- Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Deok Soo Kim
- Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jung Yeon Shim
- Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Moon Soo Park
- Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hee Yeon Woo
- Department of Laboratory Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hyosoon Park
- Department of Laboratory Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hye Lim Jung
- Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
| | - Min Jung Kwon
- Department of Laboratory Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
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26
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Leibovitch M, Hanic-Joyce PJ, Joyce PBM. In vitro studies of disease-linked variants of human tRNA nucleotidyltransferase reveal decreased thermal stability and altered catalytic activity. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1866:527-540. [PMID: 29454993 DOI: 10.1016/j.bbapap.2018.02.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 02/09/2018] [Accepted: 02/14/2018] [Indexed: 11/15/2022]
Abstract
Mutations in the human TRNT1 gene encoding tRNA nucleotidyltransferase (tRNA-NT), an essential enzyme responsible for addition of the CCA (cytidine-cytidine-adenosine) sequence to the 3'-termini of tRNAs, have been linked to disease phenotypes including congenital sideroblastic anemia with B-cell immunodeficiency, periodic fevers and developmental delay (SIFD) or retinitis pigmentosa with erythrocyte microcytosis. The effects of these disease-linked mutations on the structure and function of tRNA-NT have not been explored. Here we use biochemical and biophysical approaches to study how five SIFD-linked amino acid substitutions (T154I, M158V, L166S, R190I and I223T), residing in the N-terminal head and neck domains of the enzyme, affect the structure and activity of human tRNA-NT in vitro. Our data suggest that the SIFD phenotype is linked to poor stability of the T154I and L166S variant proteins, and to a combination of reduced stability and altered catalytic efficiency in the M158 V, R190I and I223T variants.
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Affiliation(s)
- M Leibovitch
- Department of Chemistry and Biochemistry and Centre for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke St. W., Montréal H4B 1R6, Québec, Canada
| | - P J Hanic-Joyce
- Department of Chemistry and Biochemistry and Centre for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke St. W., Montréal H4B 1R6, Québec, Canada
| | - P B M Joyce
- Department of Chemistry and Biochemistry and Centre for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke St. W., Montréal H4B 1R6, Québec, Canada.
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27
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Thota S, Gerds AT. Myelodysplastic and myeloproliferative neoplasms: updates on the overlap syndromes. Leuk Lymphoma 2017; 59:803-812. [PMID: 28771058 DOI: 10.1080/10428194.2017.1357179] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Myelodysplastic and myeloproliferative neoplasms (MDS/MPN) is a rare and distinct group of myeloid neoplasms with overlapping MDS and MPN features. Next generation sequencing studies have led to an improved understanding of MDS/MPN disease biology by identifying recurrent somatic mutations. Combining the molecular findings to patho-morphologic features has improved the precision of diagnosis and prognostic models in MDS/MPN. We discuss and highlight these updates in MDS/MPN nomenclature and diagnostic criteria per revised 2016 WHO classification of myeloid neoplasms in this article. There is an ongoing effort for data integration allowing for comprehensive genomic characterization, development of improved prognostic tools, and investigation for novel therapies using an international front specific for MDS/MPN. In this article, we discuss updates in prognostic models and current state of treatment for MDS/MPN.
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Affiliation(s)
- Swapna Thota
- a Leukemia and Myeloid Disorders Program , Taussig Cancer Institute, Cleveland Clinic Foundation , Cleveland , OH , USA
| | - Aaron T Gerds
- a Leukemia and Myeloid Disorders Program , Taussig Cancer Institute, Cleveland Clinic Foundation , Cleveland , OH , USA
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28
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Hlaváčková A, Štikarová J, Pimková K, Chrastinová L, Májek P, Kotlín R, Čermák J, Suttnar J, Dyr JE. Enhanced plasma protein carbonylation in patients with myelodysplastic syndromes. Free Radic Biol Med 2017; 108:1-7. [PMID: 28300669 DOI: 10.1016/j.freeradbiomed.2017.03.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 03/01/2017] [Accepted: 03/11/2017] [Indexed: 12/18/2022]
Abstract
Myelodysplastic syndromes (MDS) represent a heterogeneous group of pre-leukemic disorders, characterized by ineffective hematopoiesis and the abnormal blood cell development of one or more lineages. Oxidative stress, as an important factor in the carcinogenesis of onco-hematological diseases, is also one of the known factors involved in the pathogenesis of MDS. An increase of reactive oxygen species (ROS) may lead to the oxidation of DNA, lipids, and proteins, thereby causing cell damage. Protein carbonylation caused by ROS is defined as an irreversible post-translational oxidative modification of amino acid side chains, and could play an important role in signaling processes. The detection of protein carbonyl groups is a specific useful marker of oxidative stress. In this study, we examined 32 patients divided into three different subtypes of MDS according to the World Health Organization (WHO) classification criteria as refractory anemia with ringed sideroblasts (RARS), refractory cytopenia with multilineage dysplasia (RCMD), refractory anemia with excess blasts-1,2 (RAEB-1,2). We found significant differences in protein carbonylation between the group of all MDS patients and healthy controls (P=0.0078). Furthermore, carbonylated protein levels were significantly elevated in RARS patients compared to healthy donors (P=0.0013) and to RCMD patients (P=0.0277). We also found a significant difference in the total iron binding capacity (TIBC) between individual subgroups of MDS patients (P=0.0263). Moreover, TIBC was decreased in RARS patients compared to RCMD patients (P=0.0203). TIBC moderately negatively correlated with carbonyl levels (r=-0.5978, P=0.0054) in the MDS patients as a whole. Additionally we observed changes in the carbonylated proteins of RARS patients in comparison with healthy controls and their negative controls. Using tandem mass spectrometry (LC-MS/MS) we identified 27 uniquely carbonylated proteins of RARS patients, which were generated by ROS and could influence the pathophysiology of low-risk MDS. These data indicate that increased protein carbonylation is related with RARS as low-risk MDS subgroup. We suggest that this type of post-translational modification in MDS disease is not "only" a consequence of oxidative stress, but also plays an active role in the pathophysiology and iron metabolism within the RARS subgroup of MDS. Measurement of plasma carbonyl levels and the isolation of carbonylated plasma proteins, followed by their identification, could serve as a potential diagnostic and prognostic tool in MDS.
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Affiliation(s)
- Alžběta Hlaváčková
- Department of Biochemistry, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czechia.
| | - Jana Štikarová
- Department of Biochemistry, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czechia
| | - Kristýna Pimková
- Department of Biochemistry, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czechia
| | - Leona Chrastinová
- Department of Biochemistry, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czechia
| | - Pavel Májek
- Department of Biochemistry, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czechia
| | - Roman Kotlín
- Department of Biochemistry, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czechia
| | - Jaroslav Čermák
- Clinical Department, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czechia
| | - Jiří Suttnar
- Department of Biochemistry, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czechia
| | - Jan Evangelista Dyr
- Department of Biochemistry, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czechia
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Jenkins JL, Kielkopf CL. Splicing Factor Mutations in Myelodysplasias: Insights from Spliceosome Structures. Trends Genet 2017; 33:336-348. [PMID: 28372848 PMCID: PMC5447463 DOI: 10.1016/j.tig.2017.03.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 02/28/2017] [Accepted: 03/02/2017] [Indexed: 01/08/2023]
Abstract
Somatic mutations of pre-mRNA splicing factors recur among patients with myelodysplastic syndrome (MDS) and related malignancies. Although these MDS-relevant mutations alter the splicing of a subset of transcripts, the mechanisms by which these single amino acid substitutions change gene expression remain controversial. New structures of spliceosome intermediates and associated protein complexes shed light on the molecular interactions mediated by 'hotspots' of the SF3B1 and U2AF1 pre-mRNA splicing factors. The frequently mutated SF3B1 residues contact the pre-mRNA splice site. Based on structural homology with other spliceosome subunits, and recent findings of altered RNA binding by mutant U2AF1 proteins, we suggest that affected U2AF1 residues also contact pre-mRNA. Altered pre-mRNA recognition emerges as a molecular theme among MDS-relevant mutations of pre-mRNA splicing factors.
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Affiliation(s)
- Jermaine L Jenkins
- Center for RNA Biology and Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Clara L Kielkopf
- Center for RNA Biology and Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
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Gajendra S. Comment: In Response to "Megaloblastic Anemia with Ring Sideroblasts is not Always Myelodysplastic Syndrome". Turk J Haematol 2017; 34:100-101. [PMID: 27956372 PMCID: PMC5451669 DOI: 10.4274/tjh.2016.0466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Affiliation(s)
- Smeeta Gajendra
- Medanta-the Medicity, Department of Pathology and Laboratory Medicine, Gurgaon, India Phone: +09013590875 E-mail:
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31
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Guan H, Yang H, Yang M, Yanagisawa D, Bellier JP, Mori M, Takahata S, Nonaka T, Zhao S, Tooyama I. Mitochondrial ferritin protects SH-SY5Y cells against H 2O 2-induced oxidative stress and modulates α-synuclein expression. Exp Neurol 2017; 291:51-61. [PMID: 28163159 DOI: 10.1016/j.expneurol.2017.02.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 01/20/2017] [Accepted: 02/01/2017] [Indexed: 11/29/2022]
Abstract
Mitochondrial ferritin (FtMt) is a type of ferritin that sequesters iron. Previous studies have shown that FtMt is expressed by dopaminergic neurons in the substantia nigra and that it may be involved in the pathology of Parkinson's disease. However, the functional roles of FtMt in dopaminergic neurons remain unclear. In this study, we investigated the function of FtMt in α-synuclein regulation and its antioxidant roles in dopaminergic cells using human dopaminergic neuroblastoma cells, SH-SY5Y. In physiological conditions, FtMt knockdown increased α-synuclein expression at the protein level but not at the mRNA level. By contrast, FtMt overexpression reduced α-synuclein expression at the protein level but not at the mRNA level. FtMt enhanced the iron levels in mitochondria but decreased the iron levels in the intracellular labile iron pool. We found that FeCl2 could abolish the effects of FtMt overexpression on α-synuclein expression. Under oxidative stress conditions induced by H2O2, we found that H2O2 treatment induced FtMt and α-synuclein expression at both the mRNA and protein levels in a dose-dependent manner. FtMt overexpression protected cells against oxidative stress and alleviated the enhanced α-synuclein expression induced by H2O2 at the posttranscriptional level. Our results indicate that FtMt modulates α-synuclein expression at the posttranscriptional level via iron regulation in physiological conditions. FtMt expression is enhanced under oxidative stress conditions, where FtMt protects cells against the oxidative stress as well as plays an important role in maintaining α-synuclein levels.
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Affiliation(s)
- Hongpeng Guan
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan; Department of Neurosurgery, 1st Affiliated Hospital, Harbin Medical University, Harbin 150001, China
| | - Hongkuan Yang
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan; Department of Neurosurgery, 1st Affiliated Hospital, Harbin Medical University, Harbin 150001, China
| | - Mingchun Yang
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan; Department of Neurosurgery, 1st Affiliated Hospital, Harbin Medical University, Harbin 150001, China
| | - Daijiro Yanagisawa
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Jean-Pierre Bellier
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Masaki Mori
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Shogo Takahata
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan
| | - Takashi Nonaka
- Dementia Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Shiguang Zhao
- Department of Neurosurgery, 1st Affiliated Hospital, Harbin Medical University, Harbin 150001, China.
| | - Ikuo Tooyama
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-2192, Japan.
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Abstract
INTRODUCTION This study aimed to assess the kind of haematological abnormalities that are present in patients with mitochondrial disorders (MIDs) and the frequency of their occurrence. METHODS The blood cell counts of a cohort of patients with syndromic and non-syndromic MIDs were retrospectively reviewed. MIDs were classified as 'definite', 'probable' or 'possible' according to clinical presentation, instrumental findings, immunohistological findings on muscle biopsy, biochemical abnormalities of the respiratory chain and/or the results of genetic studies. Patients who had medical conditions other than MID that account for the haematological abnormalities were excluded. RESULTS A total of 46 patients ('definite' = 5; 'probable' = 9; 'possible' = 32) had haematological abnormalities attributable to MIDs. The most frequent haematological abnormality in patients with MIDs was anaemia. 27 patients had anaemia as their sole haematological problem. Anaemia was associated with thrombopenia (n = 4), thrombocytosis (n = 2), leucopenia (n = 2), and eosinophilia (n = 1). Anaemia was hypochromic and normocytic in 27 patients, hypochromic and microcytic in six patients, hyperchromic and macrocytic in two patients, and normochromic and microcytic in one patient. Among the 46 patients with a mitochondrial haematological abnormality, 78.3% had anaemia, 13.0% had thrombopenia, 8.7% had leucopenia and 8.7% had eosinophilia, alone or in combination with other haematological abnormalities. CONCLUSION MID should be considered if a patient's abnormal blood cell counts (particularly those associated with anaemia, thrombopenia, leucopenia or eosinophilia) cannot be explained by established causes. Abnormal blood cell counts may be the sole manifestation of MID or a collateral feature of a multisystem problem.
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Affiliation(s)
| | - Marlies Frank
- First Medical Department, Krankenanstalt Rudolfstiftung, Austria
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Daw S, Chatterjee R, Law A, Law S. Analysis of hematopathology and alteration of JAK1/STAT3/STAT5 signaling axis in experimental myelodysplastic syndrome. Chem Biol Interact 2016; 260:176-185. [PMID: 27725143 DOI: 10.1016/j.cbi.2016.10.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 10/04/2016] [Accepted: 10/06/2016] [Indexed: 11/27/2022]
Abstract
Hematological disorders like myelodysplastic syndrome (MDS) may arise due to cumulative dysregulation of various signalling pathways controlling proliferation, differentiation, maturation and apoptosis of bone marrow cells. This devastating bone marrow condition can be due to consequential abnormalities in haematopoiesis as well as its supportive microenvironment. Although mutations related to JAK/STAT pathway are common in myeloproliferative neoplasms, further studies are required to fully explore the myelodysplastic scenario regarding the concerned pathway. In this study, we have investigated the JAK-STAT signalling pathway which inevitably plays a crucial role in haematopoiesis. MDS was mimicked in a mouse model with an induction of ENU in adult mice. The bone marrow of the control and MDS groups of animals were subjected to a variety of tests, including cell morphology study in peripheral blood and bone marrow, cytochemistry and histochemistry of bone marrow smears, karyotyping and flowcytometric expression analysis of the phosphorylated forms of proteins like JAK1, STAT3 and STAT5 (denoted as pJAK1, pSTAT3 and pSTAT5) and the phenotypic expression of proteins like CD45 and CD71. The results revealed that the morphology of the blood and bone marrow cells were dysplastic compared to the affected blast populations of different lineages. The expression of common leucocyte antigen CD45 was less in comparison to the expression of transferrin receptor CD71 which was increased in the ENU induced MDS mouse model. Moreover, we have observed an upregulated expression of JAK1 followed by STAT5. Therefore, we can conclude that downregulation of CD45 may have helped in the upregulation of JAK-STAT signaling and CD71 expression. This aberrant signaling may be among one of the activated signaling axes that lead to affected hematopoietic lineages in Myelodysplastic syndrome.
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Affiliation(s)
- Suchismita Daw
- Stem Cell Research and Application Unit, Department of Biochemistry and Medical Biotechnology, Calcutta School of Tropical Medicine, 108, C.R Avenue, Kolkata 700073, West Bengal, India
| | - Ritam Chatterjee
- Stem Cell Research and Application Unit, Department of Biochemistry and Medical Biotechnology, Calcutta School of Tropical Medicine, 108, C.R Avenue, Kolkata 700073, West Bengal, India
| | - Aditya Law
- Stem Cell Research and Application Unit, Department of Biochemistry and Medical Biotechnology, Calcutta School of Tropical Medicine, 108, C.R Avenue, Kolkata 700073, West Bengal, India
| | - Sujata Law
- Stem Cell Research and Application Unit, Department of Biochemistry and Medical Biotechnology, Calcutta School of Tropical Medicine, 108, C.R Avenue, Kolkata 700073, West Bengal, India.
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Narang NC, Kotru M, Rao K, Sikka M. Megaloblastic Anemia with Ring Sideroblasts is not Always Myelodysplastic Syndrome. Turk J Haematol 2016; 33:358-359. [PMID: 27466740 PMCID: PMC5204198 DOI: 10.4274/tjh.2016.0090] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Affiliation(s)
| | - Mrinalini Kotru
- University College of Medical Sciences, Department of Pathology, Delhi, India, Phone: +91 981 034 52 36, E-mail:
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LeBlanc MA, Bettle A, Berman JN, Price VE, Pambrun C, Yu Z, Tiller M, McMaster CR, Fernandez CV. Study of Glycine and Folic Acid Supplementation to Ameliorate Transfusion Dependence in Congenital SLC25A38 Mutated Sideroblastic Anemia. Pediatr Blood Cancer 2016; 63:1307-9. [PMID: 27038157 DOI: 10.1002/pbc.25981] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 02/29/2016] [Indexed: 11/07/2022]
Abstract
Congenital sideroblastic anemia (CSA) is a hematological disorder characterized by the presence of ringed sideroblasts in bone marrow erythroid precursors. Mutations in the erythroid-specific glycine mitochondrial transporter gene SLC25A38 have been found in a subset of patients with transfusion-dependent congenital CSA. Further studies in a zebrafish model identified a promising ameliorative strategy with combined supplementation with glycine and folate. We tested this combination in three individuals with SLC25A38 CSA, with a primary objective to decrease red blood cell transfusion requirements. No significant impact was observed on transfusion requirements or any hematologic parameters.
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Affiliation(s)
| | - Amanda Bettle
- School of Nursing, IWK Health Centre, Halifax, Canada
| | - Jason N Berman
- Divison of Pediatric Hematology/Oncology, IWK Health Centre, Halifax, Canada
| | - Victoria E Price
- Divison of Pediatric Hematology/Oncology, IWK Health Centre, Halifax, Canada
| | - Chantale Pambrun
- Department of Hematopathology, IWK Health Centre, Halifax, Canada
| | - Zhijie Yu
- Department of Pediatrics, Dalhousie University, Halifax, Canada
| | - Marilyn Tiller
- Department of Pharmacy, IWK Health Centre, Halifax, Canada
| | | | - Conrad V Fernandez
- Divison of Pediatric Hematology/Oncology, IWK Health Centre, Halifax, Canada
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Fernández-Murray JP, Prykhozhij SV, Dufay JN, Steele SL, Gaston D, Nasrallah GK, Coombs AJ, Liwski RS, Fernandez CV, Berman JN, McMaster CR. Glycine and Folate Ameliorate Models of Congenital Sideroblastic Anemia. PLoS Genet 2016; 12:e1005783. [PMID: 26821380 PMCID: PMC4731144 DOI: 10.1371/journal.pgen.1005783] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 12/11/2015] [Indexed: 01/25/2023] Open
Abstract
Sideroblastic anemias are acquired or inherited anemias that result in a decreased ability to synthesize hemoglobin in red blood cells and result in the presence of iron deposits in the mitochondria of red blood cell precursors. A common subtype of congenital sideroblastic anemia is due to autosomal recessive mutations in the SLC25A38 gene. The current treatment for SLC25A38 congenital sideroblastic anemia is chronic blood transfusion coupled with iron chelation. The function of SLC25A38 is not known. Here we report that the SLC25A38 protein, and its yeast homolog Hem25, are mitochondrial glycine transporters required for the initiation of heme synthesis. To do so, we took advantage of the fact that mitochondrial glycine has several roles beyond the synthesis of heme, including the synthesis of folate derivatives through the glycine cleavage system. The data were consistent with Hem25 not being the sole mitochondrial glycine importer, and we identify a second SLC25 family member Ymc1, as a potential secondary mitochondrial glycine importer. Based on these findings, we observed that high levels of exogenous glycine, or 5-aminolevulinic acid (5-Ala) a metabolite downstream of Hem25 in heme biosynthetic pathway, were able to restore heme levels to normal in yeast cells lacking Hem25 function. While neither glycine nor 5-Ala could ameliorate SLC25A38 congenital sideroblastic anemia in a zebrafish model, we determined that the addition of folate with glycine was able to restore hemoglobin levels. This difference is likely due to the fact that yeast can synthesize folate, whereas in zebrafish folate is an essential vitamin that must be obtained exogenously. Given the tolerability of glycine and folate in humans, this study points to a potential novel treatment for SLC25A38 congenital sideroblastic anemia. Mutations in the SLC25A38 gene cause an inherited anemia. In this study we determine that the function of SLC25A38, and its yeast homolgue Hem25, is to act as mitochondrial glycine importers providing a molecular explanation for why patients with SLC25A38 mutations have low hemoglobin levels and become anemic. Using this new knowledge, we go on to determine that supplementation with glycine and folate restore hemoglobin levels in a zebrafish model of the disease pointing to a potentially new, safe, and cost effective treatment for SLC25A38 congenital sideroblastic anemia.
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Affiliation(s)
| | - Sergey V. Prykhozhij
- Department of Pediatrics, IWK Health Centre, Dalhousie University, Halifax, Canada
| | - J. Noelia Dufay
- Department of Pharmacology, Dalhousie University, Halifax, Canada
| | - Shelby L. Steele
- Department of Pediatrics, IWK Health Centre, Dalhousie University, Halifax, Canada
| | - Daniel Gaston
- Department of Pathology, Dalhousie University, Halifax, Canada
| | | | - Andrew J. Coombs
- Department of Pediatrics, IWK Health Centre, Dalhousie University, Halifax, Canada
| | | | - Conrad V. Fernandez
- Department of Pediatrics, IWK Health Centre, Dalhousie University, Halifax, Canada
| | - Jason N. Berman
- Department of Pediatrics, IWK Health Centre, Dalhousie University, Halifax, Canada
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Diagnosis and treatment of sideroblastic anemias: from defective heme synthesis to abnormal RNA splicing. Hematology 2015; 2015:19-25. [DOI: 10.1182/asheducation-2015.1.19] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
AbstractThe sideroblastic anemias are a heterogeneous group of inherited and acquired disorders characterized by the presence of ring sideroblasts in the bone marrow. X-linked sideroblastic anemia (XLSA) is caused by germline mutations in ALAS2. Hemizygous males have a hypochromic microcytic anemia, which is generally mild to moderate and is caused by defective heme synthesis and ineffective erythropoiesis. XLSA is a typical iron-loading anemia; although most patients are responsive to pyridoxine, treatment of iron overload is also important in the management of these patients. Autosomal recessive sideroblastic anemia attributable to mutations in SLC25A38, a member of the mitochondrial carrier family, is a severe disease: patients present in infancy with microcytic anemia, which soon becomes transfusion dependent. Conservative therapy includes regular red cell transfusion and iron chelation, whereas allogenic stem cell transplantation represents the only curative treatment. Refractory anemia with ring sideroblasts (RARS) is a myelodysplastic syndrome characterized mainly by anemia attributable to ineffective erythropoiesis. The clinical course of RARS is generally indolent, but there is a tendency to worsening of anemia over time, so that most patients become transfusion dependent in the long run. More than 90% of these patients carry somatic mutations in SF3B1, a gene encoding a core component of the RNA splicing machinery. These mutations cause misrecognition of 3′ splice sites in downstream genes, resulting in truncated gene products and/or decreased expression attributable to nonsense-mediated RNA decay; this explains the multifactorial pathogenesis of RARS. Variants of RARS include refractory cytopenia with multilineage dysplasia and ring sideroblasts, and RARS associated with marked thrombocytosis; these variants involve additional genetic lesions. Inhibitors of molecules of the transforming growth factor-β superfamily have been shown recently to target ineffective erythropoiesis and ameliorate anemia both in animal models of myelodysplastic syndrome and in RARS patients.
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Dolatshad H, Pellagatti A, Fernandez-Mercado M, Yip BH, Malcovati L, Attwood M, Przychodzen B, Sahgal N, Kanapin AA, Lockstone H, Scifo L, Vandenberghe P, Papaemmanuil E, Smith CWJ, Campbell PJ, Ogawa S, Maciejewski JP, Cazzola M, Savage KI, Boultwood J. Disruption of SF3B1 results in deregulated expression and splicing of key genes and pathways in myelodysplastic syndrome hematopoietic stem and progenitor cells. Leukemia 2015; 29:1092-103. [PMID: 25428262 PMCID: PMC4430703 DOI: 10.1038/leu.2014.331] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 10/30/2014] [Accepted: 11/19/2014] [Indexed: 02/06/2023]
Abstract
The splicing factor SF3B1 is the most commonly mutated gene in the myelodysplastic syndrome (MDS), particularly in patients with refractory anemia with ring sideroblasts (RARS). We investigated the functional effects of SF3B1 disruption in myeloid cell lines: SF3B1 knockdown resulted in growth inhibition, cell cycle arrest and impaired erythroid differentiation and deregulation of many genes and pathways, including cell cycle regulation and RNA processing. MDS is a disorder of the hematopoietic stem cell and we thus studied the transcriptome of CD34(+) cells from MDS patients with SF3B1 mutations using RNA sequencing. Genes significantly differentially expressed at the transcript and/or exon level in SF3B1 mutant compared with wild-type cases include genes that are involved in MDS pathogenesis (ASXL1 and CBL), iron homeostasis and mitochondrial metabolism (ALAS2, ABCB7 and SLC25A37) and RNA splicing/processing (PRPF8 and HNRNPD). Many genes regulated by a DNA damage-induced BRCA1-BCLAF1-SF3B1 protein complex showed differential expression/splicing in SF3B1 mutant cases. This is the first study to determine the target genes of SF3B1 mutation in MDS CD34(+) cells. Our data indicate that SF3B1 has a critical role in MDS by affecting the expression and splicing of genes involved in specific cellular processes/pathways, many of which are relevant to the known RARS pathophysiology, suggesting a causal link.
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Affiliation(s)
- H Dolatshad
- LLR Molecular Haematology Unit, NDCLS, RDM, University of Oxford, Oxford, UK
| | - A Pellagatti
- LLR Molecular Haematology Unit, NDCLS, RDM, University of Oxford, Oxford, UK
| | - M Fernandez-Mercado
- LLR Molecular Haematology Unit, NDCLS, RDM, University of Oxford, Oxford, UK
| | - B H Yip
- LLR Molecular Haematology Unit, NDCLS, RDM, University of Oxford, Oxford, UK
| | - L Malcovati
- Department of Hematology Oncology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
- Department of Molecular Medicine and Medical Therapy, University of Pavia, Pavia, Italy
| | - M Attwood
- LLR Molecular Haematology Unit, NDCLS, RDM, University of Oxford, Oxford, UK
| | - B Przychodzen
- Department of Translational Haematology and Oncology Research, Taussig Cancer Institute, Cleveland, OH, USA
| | - N Sahgal
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - A A Kanapin
- Department of Oncology, University of Oxford, Oxford, UK
| | - H Lockstone
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - L Scifo
- LLR Molecular Haematology Unit, NDCLS, RDM, University of Oxford, Oxford, UK
| | - P Vandenberghe
- Center for Human Genetics, Katholieke Universiteit Leuven/University Hospital Leuven, Leuven, Belgium
| | - E Papaemmanuil
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, UK
| | - C W J Smith
- Department of Biochemistry, Downing Site, University of Cambridge, Cambridge, UK
| | - P J Campbell
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, UK
| | - S Ogawa
- Cancer Genomics Projects, Graduate School of Medicine, Tokyo, Japan
| | - J P Maciejewski
- Department of Translational Haematology and Oncology Research, Taussig Cancer Institute, Cleveland, OH, USA
| | - M Cazzola
- Department of Hematology Oncology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
- Department of Molecular Medicine and Medical Therapy, University of Pavia, Pavia, Italy
| | - K I Savage
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, UK
| | - J Boultwood
- LLR Molecular Haematology Unit, NDCLS, RDM, University of Oxford, Oxford, UK
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Affiliation(s)
- Konrad Teodor Sawicki
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL (K.T.S., H.C.C., H.A.)
| | - Hsiang-Chun Chang
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL (K.T.S., H.C.C., H.A.)
| | - Hossein Ardehali
- Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, IL (K.T.S., H.C.C., H.A.)
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Willekens C, Dumezy F, Boyer T, Renneville A, Rossignol J, Berthon C, Cotteau-Leroy A, Mehiaoui L, Quesnel B, Preudhomme C. Linezolid induces ring sideroblasts. Haematologica 2014; 98:e138-40. [PMID: 24186315 DOI: 10.3324/haematol.2013.092395] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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41
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Visconte V, Avishai N, Mahfouz R, Tabarroki A, Cowen J, Sharghi-Moshtaghin R, Hitomi M, Rogers HJ, Hasrouni E, Phillips J, Sekeres MA, Heuer AH, Saunthararajah Y, Barnard J, Tiu RV. Distinct iron architecture in SF3B1-mutant myelodysplastic syndrome patients is linked to an SLC25A37 splice variant with a retained intron. Leukemia 2014; 29:188-95. [PMID: 24854990 DOI: 10.1038/leu.2014.170] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 04/10/2014] [Accepted: 05/19/2014] [Indexed: 12/18/2022]
Abstract
Perturbation in iron homeostasis is a hallmark of some hematologic diseases. Abnormal sideroblasts with accumulation of iron in the mitochondria are named ring sideroblasts (RS). RS is a cardinal feature of refractory anemia with RS (RARS) and RARS with marked thrombocytosis (RARS/-T). Mutations in SF3B1, a member of the RNA splicing machinery are frequent in RARS/-T and defects of this gene were linked to RS formation. Here we showcase the differences in iron architecture of SF3B1-mutant and wild-type (WT) RARS/-T and provide new mechanistic insights by which SF3B1 mutations lead to differences in iron. We found higher iron levels in SF3B1 mutant vs WT RARS/-T by transmission electron microscopy/spectroscopy/flow cytometry. SF3B1 mutations led to increased iron without changing the valence as shown by the presence of Fe(2+) in mutant and WT. Reactive oxygen species and DNA damage were not increased in SF3B1-mutant patients. RNA-sequencing and Reverse transcriptase PCR showed higher expression of a specific isoform of SLC25A37 in SF3B1-mutant patients, a crucial importer of Fe(2+) into the mitochondria. Our studies suggest that SF3B1 mutations contribute to cellular iron overload in RARS/-T by deregulating SLC25A37.
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Affiliation(s)
- V Visconte
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA
| | - N Avishai
- Department of Materials Science and Engineering, Swagelok Center for Surface Analysis of Materials, Case Western Reserve University, Cleveland, OH, USA
| | - R Mahfouz
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA
| | - A Tabarroki
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA
| | - J Cowen
- Department of Materials Science and Engineering, Swagelok Center for Surface Analysis of Materials, Case Western Reserve University, Cleveland, OH, USA
| | - R Sharghi-Moshtaghin
- Department of Materials Science and Engineering, Swagelok Center for Surface Analysis of Materials, Case Western Reserve University, Cleveland, OH, USA
| | - M Hitomi
- Electron Microscopy Facility, Case Western Reserve University, Cleveland, OH, USA
| | - H J Rogers
- Department of Clinical Pathology, Cleveland Clinic, Cleveland, OH, USA
| | - E Hasrouni
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA
| | - J Phillips
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA
| | - M A Sekeres
- 1] Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA [2] Leukemia Program, Department of Hematologic Oncology and Blood Disorders, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA
| | - A H Heuer
- Department of Materials Science and Engineering, Swagelok Center for Surface Analysis of Materials, Case Western Reserve University, Cleveland, OH, USA
| | - Y Saunthararajah
- 1] Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA [2] Leukemia Program, Department of Hematologic Oncology and Blood Disorders, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA
| | - J Barnard
- Department of Quantitative Health Sciences, Cleveland Clinic, OH, USA
| | - R V Tiu
- 1] Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA [2] Leukemia Program, Department of Hematologic Oncology and Blood Disorders, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA
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Identification of four SLC19A2 mutations in four Chinese thiamine responsive megaloblastic anemia patients without diabetes. Blood Cells Mol Dis 2013; 52:203-4. [PMID: 24355766 DOI: 10.1016/j.bcmd.2013.11.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Revised: 10/27/2013] [Accepted: 10/27/2013] [Indexed: 01/19/2023]
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Stehling O, Lill R. The role of mitochondria in cellular iron-sulfur protein biogenesis: mechanisms, connected processes, and diseases. Cold Spring Harb Perspect Biol 2013; 5:a011312. [PMID: 23906713 DOI: 10.1101/cshperspect.a011312] [Citation(s) in RCA: 148] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Iron-sulfur (Fe/S) clusters belong to the most ancient protein cofactors in life, and fulfill functions in electron transport, enzyme catalysis, homeostatic regulation, and sulfur activation. The synthesis of Fe/S clusters and their insertion into apoproteins requires almost 30 proteins in the mitochondria and cytosol of eukaryotic cells. This review summarizes our current biochemical knowledge of mitochondrial Fe/S protein maturation. Because this pathway is essential for various extramitochondrial processes, we then explain how mitochondria contribute to the mechanism of cytosolic and nuclear Fe/S protein biogenesis, and to other connected processes including nuclear DNA replication and repair, telomere maintenance, and transcription. We next describe how the efficiency of mitochondria to assemble Fe/S proteins is used to regulate cellular iron homeostasis. Finally, we briefly summarize a number of mitochondrial "Fe/S diseases" in which various biogenesis components are functionally impaired owing to genetic mutations. The thorough understanding of the diverse biochemical disease phenotypes helps with testing the current working model for the molecular mechanism of Fe/S protein biogenesis and its connected processes.
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Affiliation(s)
- Oliver Stehling
- Institut für Zytobiologie, Philipps-Universität Marburg, 35032 Marburg, Germany
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44
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Mitochondrial ferritin in neurodegenerative diseases. Neurosci Res 2013; 77:1-7. [PMID: 23916831 DOI: 10.1016/j.neures.2013.07.005] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 06/04/2013] [Accepted: 06/27/2013] [Indexed: 12/29/2022]
Abstract
Mitochondrial ferritin (FtMt) is a novel protein encoded by an intronless gene mapped to chromosome 5q23.1. Ferritin is ubiquitously expressed; however, FtMt expression is restricted to specific tissues such as the testis and the brain. The distribution pattern of FtMt suggests a functional role for this protein in the brain; however, data concerning the roles of FtMt in neurodegenerative diseases remain scarce. In the human cerebral cortex, FtMt expression was increased in Alzheimer's disease patients compared to control cases. Cultured neuroblastoma cells showed low-level expression of FtMt, which was increased by H2O2 treatment. FtMt overexpression showed a neuroprotective effect against H2O2-induced oxidative stress and Aβ-induced neurotoxicity in neuroblastoma cells. FtMt expression was also detected in dopaminergic neurons in the substantia nigra and was increased in patients with restless legs syndrome, while FtMt had a protective effect against cell death in a neuroblastoma cell line model of Parkinson's disease. FtMt is involved in other neurodegenerative diseases such as age-related macular degeneration (AMD), with an FtMt gene mutation identified in AMD patients, and Friedreich's ataxia, which is caused by a deficiency in frataxin. FtMt overexpression in frataxin-deficient cells increased cell resistance to H2O2 damage. These results implicate a neuroprotective role of FtMt in neurodegenerative diseases.
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45
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Cazzola M, Rossi M, Malcovati L. Biologic and clinical significance of somatic mutations of SF3B1 in myeloid and lymphoid neoplasms. Blood 2013; 121:260-9. [PMID: 23160465 PMCID: PMC3790951 DOI: 10.1182/blood-2012-09-399725] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Accepted: 10/31/2012] [Indexed: 12/12/2022] Open
Abstract
Precursor mRNA splicing is catalyzed by the spliceosome, a macromolecule composed of small nuclear RNAs associated with proteins. The SF3B1 gene encodes subunit 1 of the splicing factor 3b, which is important for anchoring the spliceosome to precursor mRNA. In 2011, whole-exome sequencing studies showed recurrent somatic mutations of SF3B1 and other genes of the RNA splicing machinery in patients with myelodysplastic syndrome or myelodysplastic/myeloproliferative neoplasm. SF3B1 mutations had a particularly high frequency among conditions characterized by ring sideroblasts, which is consistent with a causal relationship. SF3B1 mutants were also detected at a lower frequency in a variety of other tumor types. In chronic lymphocytic leukemia, SF3B1 was found to be the second most frequently mutated gene. In myelodysplastic syndromes, SF3B1 mutations appear to be founding genetic lesions and are associated with a low risk of leukemic evolution. In contrast, SF3B1 mutations have a lower incidence in early stages of chronic lymphocytic leukemia, are more common in advanced disease, and tend to be associated with poor prognosis, suggesting that they occur during clonal evolution of the disease. The assessment of SF3B1 mutation status may become innovative diagnostic and prognostic tools and the availability of spliceosome modulators opens novel therapeutic prospects.
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Affiliation(s)
- Mario Cazzola
- Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
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46
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Lill R, Hoffmann B, Molik S, Pierik AJ, Rietzschel N, Stehling O, Uzarska MA, Webert H, Wilbrecht C, Mühlenhoff U. The role of mitochondria in cellular iron-sulfur protein biogenesis and iron metabolism. BIOCHIMICA ET BIOPHYSICA ACTA 2012; 1823:1491-508. [PMID: 22609301 DOI: 10.1016/j.bbamcr.2012.05.009] [Citation(s) in RCA: 364] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 05/07/2012] [Accepted: 05/09/2012] [Indexed: 12/21/2022]
Abstract
Mitochondria play a key role in iron metabolism in that they synthesize heme, assemble iron-sulfur (Fe/S) proteins, and participate in cellular iron regulation. Here, we review the latter two topics and their intimate connection. The mitochondrial Fe/S cluster (ISC) assembly machinery consists of 17 proteins that operate in three major steps of the maturation process. First, the cysteine desulfurase complex Nfs1-Isd11 as the sulfur donor cooperates with ferredoxin-ferredoxin reductase acting as an electron transfer chain, and frataxin to synthesize an [2Fe-2S] cluster on the scaffold protein Isu1. Second, the cluster is released from Isu1 and transferred toward apoproteins with the help of a dedicated Hsp70 chaperone system and the glutaredoxin Grx5. Finally, various specialized ISC components assist in the generation of [4Fe-4S] clusters and cluster insertion into specific target apoproteins. Functional defects of the core ISC assembly machinery are signaled to cytosolic or nuclear iron regulatory systems resulting in increased cellular iron acquisition and mitochondrial iron accumulation. In fungi, regulation is achieved by iron-responsive transcription factors controlling the expression of genes involved in iron uptake and intracellular distribution. They are assisted by cytosolic multidomain glutaredoxins which use a bound Fe/S cluster as iron sensor and additionally perform an essential role in intracellular iron delivery to target metalloproteins. In mammalian cells, the iron regulatory proteins IRP1, an Fe/S protein, and IRP2 act in a post-transcriptional fashion to adjust the cellular needs for iron. Thus, Fe/S protein biogenesis and cellular iron metabolism are tightly linked to coordinate iron supply and utilization. This article is part of a Special Issue entitled: Cell Biology of Metals.
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Affiliation(s)
- Roland Lill
- Institut für Zytobiologie und Zytopathologie, Philipps-Universität Marburg, Robert-Koch Str. 6, 35033 Marburg, Germany.
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SF3B1 haploinsufficiency leads to formation of ring sideroblasts in myelodysplastic syndromes. Blood 2012; 120:3173-86. [PMID: 22826563 DOI: 10.1182/blood-2012-05-430876] [Citation(s) in RCA: 158] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Whole exome/genome sequencing has been fundamental in the identification of somatic mutations in the spliceosome machinery in myelodysplastic syndromes (MDSs) and other hematologic disorders. SF3B1, splicing factor 3b subunit 1 is mutated in 60%-80% of refractory anemia with ring sideroblasts (RARS) and RARS associated with thrombocytosis (RARS-T), 2 distinct subtypes of MDS and MDS/myeloproliferative neoplasms (MDSs/MPNs). An idiosyncratic feature of RARS/RARS-T is the presence of abnormal sideroblasts characterized by iron overload in the mitochondria, called RS. Based on the high frequency of mutations of SF3B1 in RARS/RARS-T, we investigated the consequences of SF3B1 alterations. Ultrastructurally, SF3B1 mutants showed altered iron distribution characterized by coarse iron deposits compared with wild-type RARS patients by transmission electron microscopy. SF3B1 knockdown experiments in K562 cells resulted in down-regulation of U2-type intron-splicing by RT-PCR. RNA-sequencing analysis of SF3B1 mutants showed differentially used genes relevant in MDS pathogenesis, such as ASXL1, CBL, EZH, and RUNX families. A SF3B pharmacologic inhibitor, meayamycin, induced the formation of RS in healthy BM cells. Further, BM aspirates of Sf3b1 heterozygous knockout mice showed RS by Prussian blue. In conclusion, we report the first experimental evidence of the association between SF3B1 and RS phenotype. Our data suggest that SF3B1 haploinsufficiency leads to RS formation.
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48
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The place of sideroblastic erythropoiesis in WHO 2008 classification of MDS; RCMD versus RCMD-RD as combined or a separate entity? Leuk Res 2012; 36:811-2. [DOI: 10.1016/j.leukres.2012.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 04/04/2012] [Accepted: 04/05/2012] [Indexed: 11/20/2022]
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Prognostic irrelevance of ring sideroblast percentage in World Health Organization–defined myelodysplastic syndromes without excess blasts. Blood 2012; 119:5674-7. [DOI: 10.1182/blood-2012-03-415356] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Abstract
The presence of ≥ 15% bone marrow (BM) ring sideroblasts (RS) and < 5% blasts is required for a diagnosis of refractory anemia with ring sideroblasts. We examined the phenotypic and prognostic relevance of this “15%” RS threshold in 200 patients with myelodysplastic syndromes (MDS) without excess blasts and with ≥ 1% RS. The impact of RS% was assessed both as a continuous and categorical variable: < 5% (n = 56), 5%-14% (n = 32), 15%-50% (n = 79), and > 50% (n = 33). RS% correlated (P < .05) directly with age, platelet count, transfusion dependency, BM cellularity, and mutant SF3B1 and inversely with hemoglobin level, multilineage dysplasia, and high-risk karyotype; but did not correlate with IDH mutations. At a median follow-up of 33 months, 156 (73%) deaths and 24 (12%) leukemic transformations were documented. Neither univariate nor multivariable analysis showed significant effect for RS% on overall or leukemia-free survival, suggesting the limited prognostic value of quantifying BM RS in MDS.
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Visconte V, Makishima H, Maciejewski JP, Tiu RV. Emerging roles of the spliceosomal machinery in myelodysplastic syndromes and other hematological disorders. Leukemia 2012; 26:2447-54. [PMID: 22678168 DOI: 10.1038/leu.2012.130] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
In humans, the majority of all protein-coding transcripts contain introns that are removed by mRNA splicing carried out by spliceosomes. Mutations in the spliceosome machinery have recently been identified using whole-exome/genome technologies in myelodysplastic syndromes (MDS) and in other hematological disorders. Alterations in splicing factor 3 subunit b1 (SF3b1) were the first spliceosomal mutations described, immediately followed by identification of other splicing factor mutations, including U2 small nuclear RNA auxillary factor 1 (U2AF1) and serine arginine-rich splicing factor 2 (SRSF2). SF3b1/U2AF1/SRSF2 mutations occur at varying frequencies in different disease subtypes, each contributing to differences in survival outcomes. However, the exact functional consequences of these spliceosomal mutations in the pathogenesis of MDS and other hematological malignancies remain largely unknown and subject to intense investigation. For SF3b1, a gain of function mutation may offer the promise of new targeted therapies for diseases that carry this molecular abnormality that can potentially lead to cure. This review aims to provide a comprehensive overview of the emerging role of the spliceosome machinery in the biology of MDS/hematological disorders with an emphasis on the functional consequences of mutations, their clinical significance, and perspectives on how they may influence our understanding and management of diseases affected by these mutations.
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Affiliation(s)
- V Visconte
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA
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