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Koury MJ, Hausrath DJ. Macrocytic anemias. Curr Opin Hematol 2024; 31:82-88. [PMID: 38334746 DOI: 10.1097/moh.0000000000000804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
Abstract
PURPOSE OF REVIEW Over the last century, the diseases associated with macrocytic anemia have been changing with more patients currently having hematological diseases including malignancies and myelodysplastic syndrome. The intracellular mechanisms underlying the development of anemia with macrocytosis can help in understanding normal erythropoiesis. Adaptations to these diseases involving erythroid progenitor and precursor cells lead to production of fewer but larger red blood cells, and understanding these mechanisms can provide information for possible treatments. RECENT FINDINGS Both inherited and acquired bone marrow diseases involving primarily impaired or delayed erythroid cell division or secondary adaptions to basic erythroid cellular deficits that results in prolonged cell division frequently present with macrocytic anemia. SUMMARY OF FINDINGS In marrow failure diseases, large accumulations of iron and heme in early stages of erythroid differentiation make cells in those stages especially susceptible to death, but the erythroid cells that can survive the early stages of terminal differentiation yield fewer but larger erythrocytes that are recognized clinically as macrocytic anemia. Other disorders that limit deoxynucleosides required for DNA synthesis affect a broader range of erythropoietic cells, but they also lead to macrocytic anemia. The source of macrocytosis in other diseases remains uncertain.
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Affiliation(s)
- Mark J Koury
- Division of Hematology and Oncology, Vanderbilt University Medical Center, Nashville, Tennessee, USA and Medical Service, Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, USA
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2
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Joshi R, Myers E, Kokhanov A. Congenital Disorders of Red Blood Cells. Neoreviews 2022; 23:e813-e828. [PMID: 36450647 DOI: 10.1542/neo.23-12-e813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
See Bonus NeoBriefs videos and downloadable teaching slides Understanding the physiologic process of red blood cell development in utero and subsequent erythropoiesis in the neonate is crucial as this determines red blood cell structure and therefore function, which is vital to neonatal health. Infants frequently experience anemia, and special consideration must be given to the evaluation of these infants to determine the correct etiology. Traditionally, anemia is conceptualized in terms of inadequate red blood cell production, increased red blood cell destruction, or whole blood loss. This framework translates well to inherited red blood cell defects, which include genetic abnormalities in bone marrow productivity or structure of the red blood cell membrane, enzymes, or hemoglobin. This article highlights fetal and neonatal erythropoiesis and the underlying etiologies of the inherited red blood cell disorders, as well as reviews the appropriate diagnostic evaluation and next steps in management. It is imperative that neonatal clinicians remain informed about these disorders to enable early recognition and treatment, and ultimately to improve outcomes in affected infants.
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Affiliation(s)
- Rhucha Joshi
- Division of Neonatal Medicine, Department of Pediatrics, University of California Irvine, Irvine, CA
| | - Erin Myers
- Department of Pediatrics, University of California Irvine, Irvine, CA
| | - Artemiy Kokhanov
- Department of Neonatology, MemorialCare Miller Children's and Women's Hospital Long Beach, Long Beach, CA
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Ma Z, Li D, Yang X, Liang J, Zhu Y. Case report: An infant boy with X-linked sideroblastic anaemia successfully treated by umbilical cord blood haematopoietic stem cell transplantation. Front Genet 2022; 13:1009988. [DOI: 10.3389/fgene.2022.1009988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 10/28/2022] [Indexed: 11/16/2022] Open
Abstract
X-linked sideroblastic anaemia (XLSA) is an inherited disorder caused by mutations in genes encoding proteins involved in the biosynthesis of haem. The pathogenic gene, as well as the pathogenesis and diagnosis of XLSA, have been fully elucidated in previous studies. However, only a few new advances have been made in managing XLSA in recent years, and blood transfusion remains the primary treatment. We report a case of umbilical cord blood haematopoietic stem cell transplantation in a male infant diagnosed with XLSA who was born with asphyxia due to severe anaemia. Early hepatic vein occlusion occurred after transplantation. However, this complication was rapidly controlled after active treatment, and the child’s quality of life improved significantly. Haematopoietic stem cell transplantation is a promising alternative treatment for XLSA.
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Iron Metabolism in the Disorders of Heme Biosynthesis. Metabolites 2022; 12:metabo12090819. [PMID: 36144223 PMCID: PMC9505951 DOI: 10.3390/metabo12090819] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 08/26/2022] [Accepted: 08/29/2022] [Indexed: 01/19/2023] Open
Abstract
Given its remarkable property to easily switch between different oxidative states, iron is essential in countless cellular functions which involve redox reactions. At the same time, uncontrolled interactions between iron and its surrounding milieu may be damaging to cells and tissues. Heme—the iron-chelated form of protoporphyrin IX—is a macrocyclic tetrapyrrole and a coordination complex for diatomic gases, accurately engineered by evolution to exploit the catalytic, oxygen-binding, and oxidoreductive properties of iron while minimizing its damaging effects on tissues. The majority of the body production of heme is ultimately incorporated into hemoglobin within mature erythrocytes; thus, regulation of heme biosynthesis by iron is central in erythropoiesis. Additionally, heme is a cofactor in several metabolic pathways, which can be modulated by iron-dependent signals as well. Impairment in some steps of the pathway of heme biosynthesis is the main pathogenetic mechanism of two groups of diseases collectively known as porphyrias and congenital sideroblastic anemias. In porphyrias, according to the specific enzyme involved, heme precursors accumulate up to the enzyme stop in disease-specific patterns and organs. Therefore, different porphyrias manifest themselves under strikingly different clinical pictures. In congenital sideroblastic anemias, instead, an altered utilization of mitochondrial iron by erythroid precursors leads to mitochondrial iron overload and an accumulation of ring sideroblasts in the bone marrow. In line with the complexity of the processes involved, the role of iron in these conditions is then multifarious. This review aims to summarise the most important lines of evidence concerning the interplay between iron and heme metabolism, as well as the clinical and experimental aspects of the role of iron in inherited conditions of altered heme biosynthesis.
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Rodriguez-Sevilla JJ, Calvo X, Arenillas L. Causes and Pathophysiology of Acquired Sideroblastic Anemia. Genes (Basel) 2022; 13:1562. [PMID: 36140729 PMCID: PMC9498732 DOI: 10.3390/genes13091562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/22/2022] [Accepted: 08/26/2022] [Indexed: 01/19/2023] Open
Abstract
The sideroblastic anemias are a heterogeneous group of inherited and acquired disorders characterized by anemia and the presence of ring sideroblasts in the bone marrow. Ring sideroblasts are abnormal erythroblasts with iron-loaded mitochondria that are visualized by Prussian blue staining as a perinuclear ring of green-blue granules. The mechanisms that lead to the ring sideroblast formation are heterogeneous, but in all of them, there is an abnormal deposition of iron in the mitochondria of erythroblasts. Congenital sideroblastic anemias include nonsyndromic and syndromic disorders. Acquired sideroblastic anemias include conditions that range from clonal disorders (myeloid neoplasms as myelodysplastic syndromes and myelodysplastic/myeloproliferative neoplasms with ring sideroblasts) to toxic or metabolic reversible sideroblastic anemia. In the last 30 years, due to the advances in genomic techniques, a deep knowledge of the pathophysiological mechanisms has been accomplished and the bases for possible targeted treatments have been established. The distinction between the different forms of sideroblastic anemia is based on the study of the characteristics of the anemia, age of diagnosis, clinical manifestations, and the performance of laboratory analysis involving genetic testing in many cases. This review focuses on the differential diagnosis of acquired disorders associated with ring sideroblasts.
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Affiliation(s)
| | - Xavier Calvo
- Laboratori de Citologia Hematològica, Department of Pathology, Hospital del Mar, 08003 Barcelona, Spain
- Group of Translational Research on Hematological Neoplasms (GRETNHE), IMIM-Hospital del Mar, 08003 Barcelona, Spain
| | - Leonor Arenillas
- Laboratori de Citologia Hematològica, Department of Pathology, Hospital del Mar, 08003 Barcelona, Spain
- Group of Translational Research on Hematological Neoplasms (GRETNHE), IMIM-Hospital del Mar, 08003 Barcelona, Spain
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6
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Exploring the mechanistic link between SF3B1 mutation and ring sideroblast formation in myelodysplastic syndrome. Sci Rep 2022; 12:14562. [PMID: 36028755 PMCID: PMC9418223 DOI: 10.1038/s41598-022-18921-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 08/22/2022] [Indexed: 12/02/2022] Open
Abstract
Acquired sideroblastic anemia, characterized by bone marrow ring sideroblasts (RS), is predominantly associated with myelodysplastic syndrome (MDS). Although somatic mutations in splicing factor 3b subunit 1 (SF3B1), which is involved in the RNA splicing machinery, are frequently found in MDS-RS, the detailed mechanism contributing to RS formation is unknown. To explore the mechanism, we established human umbilical cord blood-derived erythroid progenitor-2 (HUDEP-2) cells stably expressing SF3B1K700E. SF3B1K700E expressing cells showed higher proportion of RS than the control cells along with erythroid differentiation, indicating the direct contribution of mutant SF3B1 expression in erythroblasts to RS formation. In SF3B1K700E expressing cells, ABCB7 and ALAS2, known causative genes for congenital sideroblastic anemia, were downregulated. Additionally, mis-splicing of ABCB7 was observed in SF3B1K700E expressing cells. ABCB7-knockdown HUDEP-2 cells revealed an increased frequency of RS formation along with erythroid differentiation, demonstrating the direct molecular link between ABCB7 defects and RS formation. ALAS2 protein levels were obviously decreased in ABCB7-knockdown cells, indicating decreased ALAS2 translation owing to impaired Fe–S cluster export by ABCB7 defects. Finally, RNA-seq analysis of MDS clinical samples demonstrated decreased expression of ABCB7 by the SF3B1 mutation. Our findings contribute to the elucidation of the complex mechanisms of RS formation in MDS-RS.
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Świątczak M, Młodziński K, Sikorska K, Raczak A, Lipiński P, Daniłowicz-Szymanowicz L. Chronic Fatigue Syndrome in Patients with Deteriorated Iron Metabolism. Diagnostics (Basel) 2022; 12:diagnostics12092057. [PMID: 36140459 PMCID: PMC9498000 DOI: 10.3390/diagnostics12092057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/11/2022] [Accepted: 08/23/2022] [Indexed: 11/16/2022] Open
Abstract
Fatigue is a common, non-specific symptom that often impairs patients’ quality of life. Even though fatigue may be the first symptom of many serious diseases, it is often underestimated due to its non-specific nature. Iron metabolism disorders are a prominent example of conditions where fatigue is a leading symptom. Whether it is an iron deficiency or overload, tiredness is one of the most common features. Despite significant progress in diagnosing and treating iron pathologies, the approach to chronic fatigue syndrome in such patients is not precisely determined. Our study aims to present the current state of knowledge on fatigue in patients with deteriorated iron metabolism.
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Affiliation(s)
- Michał Świątczak
- II Department of Cardiology and Electrotherapy, Medical University of Gdańsk, Dębinki 7, 80-211 Gdańsk, Poland
| | - Krzysztof Młodziński
- II Department of Cardiology and Electrotherapy, Medical University of Gdańsk, Dębinki 7, 80-211 Gdańsk, Poland
| | - Katarzyna Sikorska
- Department of Tropical Medicine and Epidemiology, Medical University of Gdańsk, Dębinki 7, 80-211 Gdańsk, Poland
| | - Alicja Raczak
- Clinical Psychology Department, Faculty of Health Sciences, Medical University of Gdańsk, 80-210 Gdańsk, Poland
| | - Paweł Lipiński
- Department of Molecular Biology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Wólka Kosowska, 05-552 Jastrzębiec, Poland
| | - Ludmiła Daniłowicz-Szymanowicz
- II Department of Cardiology and Electrotherapy, Medical University of Gdańsk, Dębinki 7, 80-211 Gdańsk, Poland
- Correspondence:
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Hsu CC, Senussi NH, Fertrin KY, Kowdley KV. Iron overload disorders. Hepatol Commun 2022; 6:1842-1854. [PMID: 35699322 PMCID: PMC9315134 DOI: 10.1002/hep4.2012] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 04/06/2022] [Accepted: 04/16/2022] [Indexed: 01/19/2023] Open
Abstract
Iron overload disorders represent a variety of conditions that lead to increased total body iron stores and resultant end-organ damage. An elevated ferritin and transferrin-iron saturation can be commonly encountered in the evaluation of elevated liver enzymes. Confirmatory homeostatic iron regulator (HFE) genetic testing for C282Y and H63D, mutations most encountered in hereditary hemochromatosis, should be pursued in evaluation of hyperferritinemia. Magnetic resonance imaging with quantitative assessment of iron content or liver biopsy (especially if liver disease is a cause of iron overload) should be used as appropriate. A secondary cause for iron overload should be considered if HFE genetic testing is negative for the C282Y homozygous or C282Y/H63D compound heterozygous mutations. Differential diagnosis of secondary iron overload includes hematologic disorders, iatrogenic causes, or chronic liver diseases. More common hematologic disorders include thalassemia syndromes, myelodysplastic syndrome, myelofibrosis, sideroblastic anemias, sickle cell disease, or pyruvate kinase deficiency. If iron overload has been excluded, evaluation for causes of hyperferritinemia should be pursued. Causes of hyperferritinemia include chronic liver disease, malignancy, infections, kidney failure, and rheumatic conditions, such as adult-onset Still's disease or hemophagocytic lymphohistiocytosis. In this review, we describe the diagnostic testing of patients with suspected hereditary hemochromatosis, the evaluation of patients with elevated serum ferritin levels, and signs of secondary overload and treatment options for those with secondary iron overload.
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Affiliation(s)
- Christine C. Hsu
- Medstar Georgetown University HospitalMedstar Georgetown Transplant InstituteWashingtonDistrict of ColumbiaUSA
| | - Nizar H. Senussi
- Gastroenterology and HepatologyUniversity of New MexicoAlbuquerqueNew MexicoUSA
| | - Kleber Y. Fertrin
- Division of HematologyDepartment of MedicineUniversity of WashingtonWashingtonUSA
| | - Kris V. Kowdley
- Liver Institute Northwest and Elson S. Floyd College of MedicineWashington State UniversityWashingtonUSA
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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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10
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Essentiality of Trace Elements in Pregnancy, Fertility, and Gynecologic Cancers-A State-of-the-Art Review. Nutrients 2021; 14:nu14010185. [PMID: 35011060 PMCID: PMC8746721 DOI: 10.3390/nu14010185] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/23/2021] [Accepted: 12/28/2021] [Indexed: 12/18/2022] Open
Abstract
Gynecological neoplasms pose a serious threat to women's health. It is estimated that in 2020, there were nearly 1.3 million new cases worldwide, from which almost 50% ended in death. The most commonly diagnosed are cervical and endometrial cancers; when it comes to infertility, it affects ~48.5 million couples worldwide and the number is continually rising. Ageing of the population, environmental factors such as dietary habits, environmental pollutants and increasing prevalence of risk factors may affect the reproductive potential in women. Therefore, in order to identify potential risk factors for these issues, attention has been drawn to trace elements. Trace mineral imbalances can be caused by a variety of causes, starting with hereditary diseases, finishing with an incorrect diet or exposure to polluted air or water. In this review, we aimed to summarize the current knowledge regarding trace elements imbalances in the case of gynecologic cancers as well as female fertility and during pregnancy.
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11
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Nzelu D, Shangaris P, Story L, Smith F, Piyasena C, Alamelu J, Elmakky A, Pelidis M, Mayhew R, Sankaran S. X-linked sideroblastic anaemia in a female fetus: a case report and a literature review. BMC Med Genomics 2021; 14:296. [PMID: 34930268 PMCID: PMC8686580 DOI: 10.1186/s12920-021-01146-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 12/08/2021] [Indexed: 01/19/2023] Open
Abstract
Background X-linked sideroblastic anaemia (XLSA) is commonly due to mutations in the ALAS2 gene and predominantly affects hemizygous males. Heterozygous female carriers of the ALAS2 gene mutation are often asymptomatic or only mildly anaemic. XLSA is usually characterized by microcytic erythrocytes (reduced mean corpuscular volume (MCV)) and hypochromia, along with increased red cell distribution width. However, in females with XLSA the characteristic laboratory findings can be dimorphic and present with macrocytic (elevated MCV) in addition to microcytic red cells. Case presentation We report a case of fetal anaemia, presenting in the early third trimester of pregnancy, in a female fetus. Ultrasound findings at 29 weeks were of cardiomegaly, prominent umbilical veins, a small rim of ascites, and mean cerebral artery peak systolic velocity (PSV) value above 1.5 Multiples of the Median (MoM). She underwent non-invasive prenatal testing that determined the rhesus genotype of the fetus to be rhesus B negative. No red blood cell antibodies were reported. Other investigations to determine the underlying cause of fetal anaemia included microarray comparative genomic hybridization, serology to exclude congenital infection and a peripheral blood film and fetal bilirubin to detect haemolysis. The maternal grandmother had a history of sideroblastic anaemia diagnosed at the age of 17 years. The mother had mild macrocytic anaemia with haemoglobin of 10.4 g/dl and MCV of 104 fl. The fetal anaemia was successfully treated with two in utero transfusions (IUTs), and delivery occurred via caesarean section at 37 weeks of gestation. The red cell gene sequencing in both the mother and fetus were heterozygous for an ALAS2 mutation causing in utero manifestations of XLSA. The haemoglobin on discharge to the local hospital at five days of age was 19.1 g/dl. Subsequently, the infant became anaemic, requiring regular 3–4 monthly blood transfusions and demonstrating overall normal development. Her anaemia was unresponsive to pyridoxine. Conclusions This is one of four cases reporting multiple female members presenting with discordant clinical features of XLSA from being entirely asymptomatic to hydropic in utero. Our report is novel in that there are no previous cases in the literature of anaemia in a female fetus heterozygous for ALAS2 mutation.
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Affiliation(s)
- Diane Nzelu
- Guy's & St. Thomas' Hospital NHS Foundation Trust, Westminster Bridge Road, London, SE1 7EH, UK
| | - Panicos Shangaris
- Guy's & St. Thomas' Hospital NHS Foundation Trust, Westminster Bridge Road, London, SE1 7EH, UK. .,Department of Women and Children's Health, School of Life Course & Population Sciences, Faculty of Life Sciences and Medicine, King's College London, 10th Floor North Wing St Thomas' Hospital, London, SE1 7EH, UK.
| | - Lisa Story
- Guy's & St. Thomas' Hospital NHS Foundation Trust, Westminster Bridge Road, London, SE1 7EH, UK.,Department of Women and Children's Health, School of Life Course & Population Sciences, Faculty of Life Sciences and Medicine, King's College London, 10th Floor North Wing St Thomas' Hospital, London, SE1 7EH, UK
| | - Frances Smith
- Viapath at King's College Hospital, Bessemer Wing, Denmark Hill, London, SE5 9RS, UK
| | - Chinthika Piyasena
- Guy's & St. Thomas' Hospital NHS Foundation Trust, Westminster Bridge Road, London, SE1 7EH, UK
| | - Jayanthi Alamelu
- Guy's & St. Thomas' Hospital NHS Foundation Trust, Westminster Bridge Road, London, SE1 7EH, UK
| | - Amira Elmakky
- Guy's & St. Thomas' Hospital NHS Foundation Trust, Westminster Bridge Road, London, SE1 7EH, UK
| | - Maria Pelidis
- Guy's & St. Thomas' Hospital NHS Foundation Trust, Westminster Bridge Road, London, SE1 7EH, UK
| | - Rachel Mayhew
- Viapath at King's College Hospital, Bessemer Wing, Denmark Hill, London, SE5 9RS, UK
| | - Srividhya Sankaran
- Guy's & St. Thomas' Hospital NHS Foundation Trust, Westminster Bridge Road, London, SE1 7EH, UK.,Department of Women and Children's Health, School of Life Course & Population Sciences, Faculty of Life Sciences and Medicine, King's College London, 10th Floor North Wing St Thomas' Hospital, London, SE1 7EH, UK
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12
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Patnaik MM, Tefferi A. Myelodysplastic syndromes with ring sideroblasts (MDS-RS) and MDS/myeloproliferative neoplasm with RS and thrombocytosis (MDS/MPN-RS-T) - "2021 update on diagnosis, risk-stratification, and management". Am J Hematol 2021; 96:379-394. [PMID: 33428785 DOI: 10.1002/ajh.26090] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Accepted: 01/04/2021] [Indexed: 12/17/2022]
Abstract
DISEASE OVERVIEW Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include myelodysplastic syndromes with RS (MDS-RS) and MDS/myeloproliferative neoplasm with RS and thrombocytosis (MDS/MPN-RS-T). DIAGNOSIS MDS-RS is a lower risk MDS, with single or multilineage dysplasia (MDS-RS-SLD/MLD), <5% bone marrow (BM) blasts, <1% peripheral blood blasts and ≥15% BM RS (≥5% in the presence of SF3B1 mutations). MDS/MPN-RS-T, now a formal entity in the MDS/MPN overlap syndromes, has diagnostic features of MDS-RS-SLD, along with a platelet count ≥450 × 109 /L and large atypical megakaryocytes. MUTATIONS AND KARYOTYPE Mutations in SF3B1 are seen in ≥80% of patients with MDS-RS-SLD and MDS/MPN-RS-T, and strongly correlate with the presence of BM RS; MDS/MPN-RS-T patients also demonstrate JAK2V617F (50%), DNMT3A, TET2 and ASXL1 mutations. Cytogenetic abnormalities are uncommon in both. RISK STRATIFICATION Most patients with MDS-RS-SLD are stratified into lower risk groups by the revised-IPSS. Disease outcome in MDS/MPN-RS-T is better than that of MDS-RS-SLD, but worse than that of essential thrombocythemia (MPN). Both diseases are associated with a low risk of leukemic transformation. TREATMENT Anemia and iron overload are complications seen in both and are managed similar to lower risk MDS and MPN. Luspatercept, a first-in-class erythroid maturation agent is now approved for the management of anemia in patients with MDS-RS and MDS/MPN-RS-T. Aspirin therapy is reasonable in MDS/MPN-RS-T, especially in the presence of JAK2V617F, but the value of platelet-lowering drugs remains to be defined.
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Affiliation(s)
- Mrinal M. Patnaik
- Division of Hematology, Department of Internal Medicine Mayo Clinic Rochester Minnesota
| | - Ayalew Tefferi
- Division of Hematology, Department of Internal Medicine Mayo Clinic Rochester Minnesota
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Uminski K, Houston DS, Hartley JN, Liu J, Cuvelier GDE, Israels SJ. Clinical characterization and hematopoietic stem cell transplant outcomes for congenital sideroblastic anemia caused by a novel pathogenic variant in SLC25A38. Pediatr Blood Cancer 2020; 67:e28623. [PMID: 32790119 DOI: 10.1002/pbc.28623] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/12/2020] [Accepted: 07/13/2020] [Indexed: 01/19/2023]
Abstract
BACKGROUND Congenital sideroblastic anemia (CSA) constitutes an uncommon category of inherited anemia often associated with pathologic iron accumulation. Pathogenic variants in several genes have been identified as causative for CSA. Autosomal recessive pathogenic variants in the mitochondrial glycine transporter SLC25A38 have been implicated in a subset of patients with CSA. PROCEDURE We describe seven individuals of Canadian Cree descent with a known or inferred homozygous novel founder missense variant in SLC25A38 (c.560G>A, p.Arg187Gln). RESULTS All individuals presented as young children (median age 6 months) with severe microcytic, hypochromic anemia associated with pretransfusion iron overload, requiring red cell transfusion support and iron chelation. Six individuals received pyridoxine supplementation; two demonstrating transient partial responses. Three individuals underwent allogeneic hematopoietic stem cell transplantation (HSCT). One individual with significant iron loading died in the posttransplant period due to complications of sepsis. The other two individuals remain transfusion-free following HSCT. CONCLUSIONS Despite a common genetic etiology, phenotypic variability was noted in this cohort. A transient response to pyridoxine was noted in two individuals but should not be considered a long-term therapeutic strategy. HSCT was curative when performed before significant iron loading occurred. Early identification of CSA and timely HSCT can result in excellent long-term outcomes.
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Affiliation(s)
- Kelsey Uminski
- Department of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Donald S Houston
- Department of Internal Medicine, Section of Hematology and Medical Oncology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Jessica N Hartley
- Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Jing Liu
- Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Geoffrey D E Cuvelier
- Departments of Pediatric Hematology-Oncology, Cancer Care Manitoba, and Pediatrics and Child Health, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Sara J Israels
- Departments of Pediatric Hematology-Oncology, Cancer Care Manitoba, and Pediatrics and Child Health, University of Manitoba, Winnipeg, Manitoba, Canada
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14
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Sumbele IUN, Asoba GN, Teh RN, Metuge S, Anchang-Kimbi JK, Nkuo-Akenji T. Burden of moderate to severe anaemia and severe stunting in children < 3 years in conflict-hit Mount Cameroon: a community based descriptive cross-sectional study. BMC Pediatr 2020; 20:396. [PMID: 32838765 PMCID: PMC7445924 DOI: 10.1186/s12887-020-02296-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 08/13/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Armed conflict is a significant social determinant of child health with nuanced effects. There is a dearth of knowledge on the public health issues facing vulnerable populations in conflict-stricken areas. The objective was to determine the prevalence and determinants of moderate to severe anaemia (MdSA) and severe stunting (SS) in children ≤3 years in conflict-hit Dibanda, Ekona and Muea in the Mount Cameroon area. METHODS Haematological parameters were obtained using an automated haematology analyser while undernutrition indices standard deviation (SD) scores (z- scores), were computed based on the WHO growth reference curves for 649 children in a community based cross-sectional study in 2018. Binomial logistic regression models were used to evaluate the determinants of MdSA and SS against a set of predictor variables. RESULTS Anaemia was prevalent in 84.0% (545) of the children with a majority having microcytic anaemia (59.3%). The prevalence of MdSA was 56.1% (364). Educational level of parents/caregiver (P < 0.001) and site (P = 0.043) had a significant negative effect on the occurrence of MdSA. Stunting, underweight and wasting occurred in 31.3, 13.1 and 6.3% of the children, respectively. Overall, SS was prevalent in 17.1% (111) of the children. The age groups (0.1-1.0 year, P = 0.042 and 1.1-2.0 years, P = 0.008), educational levels (no formal education, P < 0.001 and primary education P = 0.028) and SS (P = 0.035) were significant determinants of MdSA while MdSA (P = 0.035) was the only significant determinant of SS. On the contrary, age group 0.1-1 year (OR = 0.56, P = 0.043) and site (Dibanda, OR = 0.29, P = 0.001) demonstrated a significant protective effect against SS. CONCLUSIONS Moderate to severe anaemia, severe stunting and wasting especially in children not breastfed at all are public health challenges in the conflict-hit area. There is a need for targeted intervention to control anaemia as well as increased awareness of exclusive breast feeding in conflict-hit areas to limit the burden of wasting and stunting.
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Affiliation(s)
- Irene Ule Ngole Sumbele
- Department of Zoology and Animal Physiology, University of Buea, Buea, Cameroon
- Department of Microbiology and Immunology, Cornell College of Veterinary Medicine, Ithaca, New York USA
| | - Gillian Nkeudem Asoba
- Department of Zoology and Animal Physiology, University of Buea, Buea, Cameroon
- Department of Social Economy and Family Management, Higher Technical Teachers’ Training College, University of Buea, Kumba, Cameroon
| | - Rene Ning Teh
- Department of Zoology and Animal Physiology, University of Buea, Buea, Cameroon
- Department of Microbiology and Immunology, Cornell College of Veterinary Medicine, Ithaca, New York USA
| | - Samuel Metuge
- Department of Social Economy and Family Management, Higher Technical Teachers’ Training College, University of Buea, Kumba, Cameroon
| | | | - Theresa Nkuo-Akenji
- Department of Microbiology and Parasitology, University of Buea, Buea, SW Region Cameroon
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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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Wang Y, Liu X, Xie B, Yuan H, Zhang Y, Zhu J. The NOTCH1-dependent HIF1α/VGLL4/IRF2BP2 oxygen sensing pathway triggers erythropoiesis terminal differentiation. Redox Biol 2020; 28:101313. [PMID: 31539803 PMCID: PMC6812007 DOI: 10.1016/j.redox.2019.101313] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 08/14/2019] [Accepted: 08/30/2019] [Indexed: 12/17/2022] Open
Abstract
Hypoxia is widely considered as a limiting factor in vertebrate embryonic development, which requires adequate oxygen delivery for efficient energy metabolism, while nowadays some researches have revealed that hypoxia can induce stem cells so as to improve embryonic development. Erythroid differentiation is the oxygen delivery method employed by vertebrates at the very early step of embryo development, however, the mechanism how erythroid progenitor cell was triggered into mature erythrocyte is still not clear. In this study, after detecting the upregulation of vgll4b in response to oxygen levels, we generated vgll4b mutant zebrafish using CRISPR/Cas9, and verified the resulting impaired heme and dysfunctional erythroid terminal differentiation phenotype. Neither the vgll4b-deficient nor the γ-secretase inhibitor IX (DAPT)-adapted zebrafish were able to mediate HIF1α-induced heme generation. In addition, we showed that vgll4b mutant zebrafish were associated with an impaired erythroid phenotype, induced by the downregulation of alas2, which could be rescued by irf2bp2 depletion. Further mechanistic studies revealed that zebrafish VGLL4 sequesters IRF2BP2, thereby inhibiting its repression of alas2 expression and heme biosynthesis. These processes occur primarily via the VGLL4 TDU1 and IRF2BP2 ring finger domains. Our study also indicates that VGLL4 is a key player in the mediation of NOTCH1-dependent HIF1α-regulated erythropoiesis and can be sensitively regulated by oxygen concentrations. On the other hand, VGLL4 is a pivotal regulator of heme biosynthesis and erythroid terminal differentiation, which collectively improve oxygen metabolism.
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Affiliation(s)
- Yiqin Wang
- CNRS-LIA Hematology and Cancer, Sino-French Research Center for Life Sciences and Genomics, State Key Laboratory of Medical Genomics, Rui-Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Xiaohui Liu
- CNRS-LIA Hematology and Cancer, Sino-French Research Center for Life Sciences and Genomics, State Key Laboratory of Medical Genomics, Rui-Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Baoshu Xie
- Department of Neurosurgery, The First Affliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
| | - Hao Yuan
- CNRS-LIA Hematology and Cancer, Sino-French Research Center for Life Sciences and Genomics, State Key Laboratory of Medical Genomics, Rui-Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Yiyue Zhang
- Division of Cell, Developmental and Integrative Biology, School of Medicine, South China University of Technology, Guangzhou, China.
| | - Jun Zhu
- CNRS-LIA Hematology and Cancer, Sino-French Research Center for Life Sciences and Genomics, State Key Laboratory of Medical Genomics, Rui-Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Université de Paris 7/INSERM/CNRS UMR 944/7212, Equipe Labellisée No. 11 Ligue Nationale Contre le Cancer, Hôpital St. Louis, Paris, France.
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17
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Peoc'h K, Nicolas G, Schmitt C, Mirmiran A, Daher R, Lefebvre T, Gouya L, Karim Z, Puy H. Regulation and tissue-specific expression of δ-aminolevulinic acid synthases in non-syndromic sideroblastic anemias and porphyrias. Mol Genet Metab 2019; 128:190-197. [PMID: 30737140 DOI: 10.1016/j.ymgme.2019.01.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 01/21/2019] [Accepted: 01/21/2019] [Indexed: 02/07/2023]
Abstract
Recently, new genes and molecular mechanisms have been identified in patients with porphyrias and sideroblastic anemias (SA). They all modulate either directly or indirectly the δ-aminolevulinic acid synthase (ALAS) activity. ALAS, is encoded by two genes: the erythroid-specific (ALAS2), and the ubiquitously expressed (ALAS1). In the liver, ALAS1 controls the rate-limiting step in the production of heme and hemoproteins that are rapidly turned over in response to metabolic needs. Several heme regulatory targets have been identified as regulators of ALAS1 activity: 1) transcriptional repression via a heme-responsive element, 2) post-transcriptional destabilization of ALAS1 mRNA, 3) post-translational inhibition via a heme regulatory motif, 4) direct inhibition of the activity of the enzyme and 5) breakdown of ALAS1 protein via heme-mediated induction of the protease Lon peptidase 1. In erythroid cells, ALAS2 is a gatekeeper of production of very large amounts of heme necessary for hemoglobin synthesis. The rate of ALAS2 synthesis is transiently increased during the period of active heme synthesis. Its gene expression is determined by trans-activation of nuclear factor GATA1, CACC box and NF-E2-binding sites in the promoter areas. ALAS2 mRNA translation is also regulated by the iron-responsive element (IRE)/iron regulatory proteins (IRP) binding system. In patients, ALAS enzyme activity is affected in most of the mutations causing non-syndromic SA and in several porphyrias. Decreased ALAS2 activity results either directly from loss-of-function ALAS2 mutations as seen in X-linked sideroblastic anemia (XLSA) or from defect in the availability of one of its two mitochondrial substrates: glycine in SLC25A38 mutations and succinyl CoA in GLRX5 mutations. Moreover, ALAS2 gain of function mutations is responsible for X-linked protoporphyria and increased ALAS1 activity lead to acute attacks of hepatic porphyrias. A missense dominant mutation in the Walker A motif of the ATPase binding site in the gene coding for the mitochondrial protein unfoldase CLPX also contributes to increasing ALAS and subsequently protoporphyrinemia. Altogether, these recent data on human ALAS have informed our understanding of porphyrias and sideroblastic anemias pathogeneses and may contribute to new therapeutic strategies.
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Affiliation(s)
- Katell Peoc'h
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l'inflammation, Université Paris Diderot, site Bichat, Sorbonne Paris Cité, France, 16 rue Henri Huchard, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France.
| | - Gaël Nicolas
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l'inflammation, Université Paris Diderot, site Bichat, Sorbonne Paris Cité, France, 16 rue Henri Huchard, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France.
| | - Caroline Schmitt
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l'inflammation, Université Paris Diderot, site Bichat, Sorbonne Paris Cité, France, 16 rue Henri Huchard, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France; AP-HP, HUPNVS, Centre Français des Porphyries, Hôpital Louis Mourier, Colombes, France.
| | - Arienne Mirmiran
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l'inflammation, Université Paris Diderot, site Bichat, Sorbonne Paris Cité, France, 16 rue Henri Huchard, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France.
| | - Raed Daher
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l'inflammation, Université Paris Diderot, site Bichat, Sorbonne Paris Cité, France, 16 rue Henri Huchard, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France.
| | - Thibaud Lefebvre
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l'inflammation, Université Paris Diderot, site Bichat, Sorbonne Paris Cité, France, 16 rue Henri Huchard, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France; AP-HP, HUPNVS, Centre Français des Porphyries, Hôpital Louis Mourier, Colombes, France.
| | - Laurent Gouya
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l'inflammation, Université Paris Diderot, site Bichat, Sorbonne Paris Cité, France, 16 rue Henri Huchard, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France; AP-HP, HUPNVS, Centre Français des Porphyries, Hôpital Louis Mourier, Colombes, France.
| | - Zoubida Karim
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l'inflammation, Université Paris Diderot, site Bichat, Sorbonne Paris Cité, France, 16 rue Henri Huchard, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France.
| | - Hervé Puy
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l'inflammation, Université Paris Diderot, site Bichat, Sorbonne Paris Cité, France, 16 rue Henri Huchard, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France; AP-HP, HUPNVS, Centre Français des Porphyries, Hôpital Louis Mourier, Colombes, France.
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Lian Y, Shi J, Nie N, Huang Z, Shao Y, Zhang J, Huang J, Li X, Ge M, Jin P, Wang M, Zheng Y. Reticulocyte Hemoglobin Equivalent (Ret-He) Combined with Red Blood Cell Distribution Width Has a Differentially Diagnostic Value for Thalassemias. Hemoglobin 2019; 43:229-235. [PMID: 31476929 DOI: 10.1080/03630269.2019.1655440] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
As a type of congenital microcytic hypochromic anemia, thalassemia trait is often confused with other conditions, such as congenital sideroblastic anemia (CSA) and iron deficiency anemia, before a specific work-up is performed. However, these tests, including hemoglobin (Hb) electrophoresis, gene mutations and Prussian blue staining after bone marrow aspirate, are relatively expensive, time-consuming and invasive. To find labor-saving parameters to facilitate differential diagnosis, we retrospectively analyzed the routine blood indexes of 59 thalassemia trait cases [22 α-thalassemia (α-thal), 36 β-thalassemia (β-thal) and one α/β-thal], 21 CSA patients, and 238 iron deficiency anemia controls. Significantly higher reticulocyte Hb equivalent (Ret-He) and lower red blood cell (RBC) distribution width (RDW) were prominent in thalassemia trait. Furthermore, RDW-standard deviation (SD) was independent of the severity of anemia in thalassemia trait, similar to Ret-He in CSA. In the context of the same grades of anemia, Ret-He combined with RDW was powerful in differentiation of thalassemia from CSA and iron deficiency anemia. By receiver operation curve (ROC) analysis, Ret-He had a specificity of 67.06% and a sensitivity of 76.92% with a cutoff value of 20.9 pg for thalassemia trait in mild anemia and a specificity of 84.09% and a sensitivity of 68.42% with a cutoff value of 19.1 pg for thalassemia trait in moderate anemia. Regarding CSA, Ret-He had 92.94% specificity and 60.00% sensitivity in mild anemia, with a cutoff value of 18.1 pg. Overall, Ret-He and RDW are two convenient indexes able to differentiate thalassemia from the other two microcytic anemias, CSA and iron deficiency anemia.
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Affiliation(s)
- Yu Lian
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Jun Shi
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Neng Nie
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Zhendong Huang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Yingqi Shao
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Jing Zhang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Jinbo Huang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Xingxin Li
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Meili Ge
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Peng Jin
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Min Wang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
| | - Yizhou Zheng
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin City, People's Republic of China
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Loghavi S, Wang SA. Defining the Boundary Between Myelodysplastic Syndromes and Myeloproliferative Neoplasms. Surg Pathol Clin 2019; 12:651-669. [PMID: 31352979 DOI: 10.1016/j.path.2019.03.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this article we provide a practical and comprehensive review of myeloid neoplasms with overlapping myelodysplastic (MDS) and myeloproliferative (MPN) features, with emphasis on recent updates in classification, particularly the utility of morphologic, cytogenetic, and molecular findings in better defining and classifying these disease entities. We provide the reader with a summary of the most recent developments and updates that have helped further our understanding of the genomic landscape, clinicopathologic features, and prognostic elements of myeloid neoplasms with MDS/MPN features.
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Affiliation(s)
- Sanam Loghavi
- Department of Hematopathology, The University of Texas, MD Anderson Cancer Center, Houston, TX, USA
| | - Sa A Wang
- Department of Hematopathology, The University of Texas, MD Anderson Cancer Center, Houston, TX, USA.
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20
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Patnaik MM, Tefferi A. Refractory anemia with ring sideroblasts (RARS) and RARS with thrombocytosis: "2019 Update on Diagnosis, Risk-stratification, and Management". Am J Hematol 2019; 94:475-488. [PMID: 30618061 DOI: 10.1002/ajh.25397] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 01/02/2019] [Indexed: 12/17/2022]
Abstract
DISEASE OVERVIEW Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include refractory anemia with ring sideroblasts (RARS), now classified under myelodysplastic syndromes with RS (MDS-RS) and RARS with thrombocytosis (RARS-T); now called myelodysplastic/myeloproliferative neoplasm with RS and thrombocytosis (MDS/MPN-RS-T). DIAGNOSIS MDS-RS is a lower-risk MDS, with single or multilineage dysplasia (SLD/MLD), <5% bone marrow (BM) blasts and ≥ 15% BM RS (≥5% in the presence of SF3B1 mutations). MDS/MPN-RS-T, now a formal entity in the MDS/MPN overlap syndromes, has diagnostic features of MDS-RS-SLD, along with a platelet count ≥450 × 10(9)/L and large atypical megakaryocytes. MUTATIONS AND KARYOTYPE Mutations in SF3B1 are seen in ≥80% of patients with MDS-RS-SLD and MDS/MPN-RS-T, and strongly correlate with the presence of BM RS; MDS/MPN-RS-T patients also demonstrate JAK2V617F, ASXL1, DNMT3A, SETBP1, and TET2 mutations. Cytogenetic abnormalities are uncommon in both. RISK STRATIFICATION Most patients with MDS-RS-SLD are stratified into lower-risk groups by the revised-IPSS. Disease outcome in MDS/MPN-RS-T is better than that of MDS-RS-SLD, but worse than that of essential thrombocythemia. Both diseases have a low risk of leukemic transformation. TREATMENT Anemia and iron overload are complications seen in both and are managed similar to lower-risk MDS and MPN. The advent of luspatercept, a first-in-class erythroid maturation agent will tremendously boost the ability to manage anemia. Aspirin therapy is reasonable in MDS/MPN-RS-T, especially in the presence of JAK2V617F, but the value of platelet-lowering drugs remains uncertain.
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Affiliation(s)
- Mrinal M. Patnaik
- Division of Hematology, Department of Internal Medicine Mayo Clinic Rochester Minnesota
| | - Ayalew Tefferi
- Division of Hematology, Department of Internal Medicine Mayo Clinic Rochester Minnesota
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Fujiwara T, Harigae H. Molecular pathophysiology and genetic mutations in congenital sideroblastic anemia. Free Radic Biol Med 2019; 133:179-185. [PMID: 30098397 DOI: 10.1016/j.freeradbiomed.2018.08.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 08/02/2018] [Accepted: 08/04/2018] [Indexed: 01/19/2023]
Abstract
Sideroblastic anemia is a heterogeneous congenital and acquired disorder characterized by anemia and the presence of ring sideroblasts in the bone marrow. Congenital sideroblastic anemia (CSA) is a rare disease caused by mutations in genes involved in the heme biosynthesis, iron-sulfur [Fe-S] cluster biosynthesis, and mitochondrial protein synthesis. The most prevalent form of CSA is X-linked sideroblastic anemia, caused by mutations in the erythroid-specific δ-aminolevulinate synthase (ALAS2), which is the first enzyme of the heme biosynthesis pathway in erythroid cells. To date, a remarkable number of genetically undefined CSA cases remain, but a recent application of the next-generation sequencing technology has recognized novel causative genes for CSA. However, in most instances, the detailed molecular mechanisms of how defects of each gene result in the abnormal mitochondrial iron accumulation remain unclear. This review aims to cover the current understanding of the molecular pathophysiology of CSA.
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Affiliation(s)
- Tohru Fujiwara
- Department of Hematology and Rheumatology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-cho, Aoba-ku, Sendai 980-8575, Japan
| | - Hideo Harigae
- Department of Hematology and Rheumatology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-cho, Aoba-ku, Sendai 980-8575, Japan.
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22
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Noronha SA. Aplastic and Hypoplastic Anemias. Pediatr Rev 2018; 39:601-611. [PMID: 30504252 DOI: 10.1542/pir.2017-0250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Suzie A Noronha
- Division of Pediatric Hematology/Oncology, University of Rochester, Rochester, NY
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Gotardelo DR, Courrol LC, Bellini MH, de Oliveira Silva FR, Soares CRJ. Porphyrins are increased in the faeces of patients with prostate cancer: a case-control study. BMC Cancer 2018; 18:1090. [PMID: 30419859 PMCID: PMC6233593 DOI: 10.1186/s12885-018-5030-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 11/01/2018] [Indexed: 01/04/2023] Open
Abstract
Background Experimental models of prostate cancer have demonstrated increased levels of protoporphyrin IX (PpIX) in the blood and faeces of mice. Hence, the quantification of these autofluorescent molecules could be hypothesized to be a potential marker for this type of tumour. In this case-control study, the autofluorescence of porphyrins in human faeces from patients with prostate cancer and control subjects was analysed using fluorescence spectroscopy. Methods First, 3 mL of analytical-grade acetone was added to 0.3 g of faeces, and the mixture was macerated and centrifuged at 4000 rpm for 15 min. The supernatant was analysed spectroscopically. The emission spectra from 550 to 750 nm were obtained by exciting the samples at 405 nm. Results A significant difference between the samples from control and cancer subjects was established in the spectral region of 670–675 nm (p = 0.000127), which corresponds to a significant increase in faecal porphyrins in patients with cancer. There was no statistically significant correlation between PSA levels and faecal porphyrins. Conclusion In this preliminary study conducted in humans, the results show a simple and non-invasive method to assess faecal porphyrins, which have the potential to function as a tumour biomarker in patients with prostate cancer. This approach has improved sensitivity and specificity over PSA testing. Additional prospective studies with larger sample sizes are required to validate these findings. Electronic supplementary material The online version of this article (10.1186/s12885-018-5030-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniel Riani Gotardelo
- Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, 2242- Cidade Universitária, São Paulo, 05508-000, Brazil. .,Instituto Tocantinense Presidente Antônio Carlos - ITPAC Palmas, Tocantins, Brazil.
| | - Lilia Coronato Courrol
- Instituto de Ciências Ambientais Químicas e Farmacêuticas (ICAQF), Departamento de Física (DF), UNIFESP, Campus Diadema, São Paulo, Brazil
| | - Maria Helena Bellini
- Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, 2242- Cidade Universitária, São Paulo, 05508-000, Brazil
| | - Flávia Rodrigues de Oliveira Silva
- Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, 2242- Cidade Universitária, São Paulo, 05508-000, Brazil
| | - Carlos Roberto Jorge Soares
- Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, 2242- Cidade Universitária, São Paulo, 05508-000, Brazil
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Congenital sideroblastic anemia: Advances in gene mutations and pathophysiology. Gene 2018; 668:182-189. [DOI: 10.1016/j.gene.2018.05.074] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 05/18/2018] [Indexed: 01/19/2023]
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Hikmat O, Tzoulis C, Klingenberg C, Rasmussen M, Tallaksen CME, Brodtkorb E, Fiskerstrand T, McFarland R, Rahman S, Bindoff LA. The presence of anaemia negatively influences survival in patients with POLG disease. J Inherit Metab Dis 2017; 40:861-866. [PMID: 28865037 DOI: 10.1007/s10545-017-0084-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 08/15/2017] [Accepted: 08/18/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND Mitochondria play an important role in iron metabolism and haematopoietic cell homeostasis. Recent studies in mice showed that a mutation in the catalytic subunit of polymerase gamma (POLG) was associated with haematopoietic dysfunction including anaemia. The aim of this study was to analyse the frequency of anaemia in a large cohort of patients with POLG related disease. METHODS We conducted a multi-national, retrospective study of 61 patients with confirmed, pathogenic biallelic POLG mutations from six centres, four in Norway and two in the United Kingdom. Clinical, laboratory and genetic data were collected using a structured questionnaire. Anaemia was defined as an abnormally low haemoglobin value adjusted for age and sex. Univariate survival analysis was performed using log-rank test to compare differences in survival time between categories. RESULTS Anaemia occurred in 67% (41/61) of patients and in 23% (14/61) it was already present at clinical presentation. The frequency of anaemia in patients with early onset disease including Alpers syndrome and myocerebrohepatopathy spectrum (MCHS) was high (72%) and 35% (8/23) of these had anaemia at presentation. Survival analysis showed that the presence of anaemia was associated with a significantly worse survival (P = 0.004). CONCLUSION Our study reveals that anaemia can be a feature of POLG-related disease. Further, we show that its presence is associated with significantly worse prognosis either because anaemia itself is impacting survival or because it reflects the presence of more serious disease. In either case, our data suggests anaemia is a marker for negative prognosis.
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Affiliation(s)
- Omar Hikmat
- Department of Pediatrics, Haukeland University Hospital, 5021, Bergen, Norway
- Department of Clinical Medicine (K1), University of Bergen, Bergen, Norway
| | - Charalampos Tzoulis
- Department of Clinical Medicine (K1), University of Bergen, Bergen, Norway
- Department of Neurology, Haukeland University Hospital, 5021, Bergen, Norway
| | - Claus Klingenberg
- Department of Paediatric and Adolescent Medicine, University Hospital of North Norway, Tromsø, Norway
- Paediatric Research Group, Department of Clinical Medicine, UiT- The Arctic University of Norway, Tromsø, Norway
| | - Magnhild Rasmussen
- Women and Children's Division, Department of Clinical Neurosciences for Children, Oslo University Hospital, Oslo, Norway
- Unit for Congenital and Hereditary Neuromuscular Disorders, Department of Neurology, Oslo University Hospital, Oslo, Norway
| | - Chantal M E Tallaksen
- Department of Neurology, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Eylert Brodtkorb
- Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Neurology and Clinical Neurophysiology, St. Olav's University Hospital, Trondheim, Norway
| | - Torunn Fiskerstrand
- Center for Medical Genetics and Molecular Medicine, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Science (K2), University of Bergen, Bergen, Norway
| | - Robert McFarland
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School Framlington Place, Newcastle University, Newcastle upon Tyne, UK
| | - Shamima Rahman
- Mitochondrial Research Group, UCL Great Ormond Street Institute of Child Health, London, UK
- Metabolic Unit, Great Ormond Street Hospital NHS Foundation trust, London, UK
| | - Laurence A Bindoff
- Department of Clinical Medicine (K1), University of Bergen, Bergen, Norway.
- Department of Neurology, Haukeland University Hospital, 5021, Bergen, Norway.
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Patnaik MM, Tefferi A. Refractory anemia with ring sideroblasts (RARS) and RARS with thrombocytosis (RARS-T): 2017 update on diagnosis, risk-stratification, and management. Am J Hematol 2017; 92:297-310. [PMID: 28188970 DOI: 10.1002/ajh.24637] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 12/23/2016] [Accepted: 12/23/2016] [Indexed: 02/06/2023]
Abstract
DISEASE OVERVIEW Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include refractory anemia with ring sideroblasts (RARS), now classified under myelodysplastic syndromes with RS (MDS-RS) and RARS with thrombocytosis (RARS-T); now called myelodysplastic/myeloproliferative neoplasm with RS and thrombocytosis (MDS/MPN-RS-T). DIAGNOSIS MDS-RS is a lower risk MDS, with single or multilineage dysplasia (SLD/MLD), <5% bone marrow (BM) blasts and ≥15% BM RS (≥5% in the presence of SF3B1 mutations). MDS/MPN-RS-T, now a formal entity in the MDS/MPN overlap syndromes, has diagnostic features of MDS-RS-SLD, along with a platelet count ≥ 450 × 10(9)/L and large atypical megakaryocytes (similar to BCR-ABL1 negative MPN). MUTATIONS AND KARYOTYPE Mutations in SF3B1 are seen in ≥80% of patients with MDS-RS-SLD and MDS/MPN-RS-T, and strongly correlate with the presence of BM RS; MDS/MPN-RS-T patients also demonstrate JAK2V617F, ASXL1, DNMT3A, SETBP1, and TET2 mutations; with ASXL1/SETBP1 mutations adversely impacting survival. Cytogenetic abnormalities are uncommon in both diseases. RISK STRATIFICATION Most patients with MDS-RS-SLD are stratified into lower risk groups by the revised-International Prognostic Scoring System (R-IPSS). Disease outcome in MDS/MPN-RS-T is better than that of MDS-RS-SLD, but worse than that of essential thrombocythemia. Both diseases have a low risk of leukemic TREATMENT: Anemia and iron overload are complications seen in both and are managed similar to lower risk MDS and MPN. Aspirin therapy is reasonable in MDS/MPN-RS-T, especially in the presence of JAK2V617F, but the value of platelet-lowering drugs is uncertain.
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Affiliation(s)
- Mrinal M. Patnaik
- Division of Hematology, Department of Internal MedicineMayo ClinicRochester Minnesota
| | - Ayalew Tefferi
- Division of Hematology, Department of Internal MedicineMayo ClinicRochester Minnesota
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Rychtarcikova Z, Lettlova S, Tomkova V, Korenkova V, Langerova L, Simonova E, Zjablovskaja P, Alberich-Jorda M, Neuzil J, Truksa J. Tumor-initiating cells of breast and prostate origin show alterations in the expression of genes related to iron metabolism. Oncotarget 2017; 8:6376-6398. [PMID: 28031527 PMCID: PMC5351639 DOI: 10.18632/oncotarget.14093] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 11/30/2016] [Indexed: 12/22/2022] Open
Abstract
The importance of iron in the growth and progression of tumors has been widely documented. In this report, we show that tumor-initiating cells (TICs), represented by spheres derived from the MCF7 cell line, exhibit higher intracellular labile iron pool, mitochondrial iron accumulation and are more susceptible to iron chelation. TICs also show activation of the IRP/IRE system, leading to higher iron uptake and decrease in iron storage, suggesting that level of properly assembled cytosolic iron-sulfur clusters (FeS) is reduced. This finding is confirmed by lower enzymatic activity of aconitase and FeS cluster biogenesis enzymes, as well as lower levels of reduced glutathione, implying reduced FeS clusters synthesis/utilization in TICs. Importantly, we have identified specific gene signature related to iron metabolism consisting of genes regulating iron uptake, mitochondrial FeS cluster biogenesis and hypoxic response (ABCB10, ACO1, CYBRD1, EPAS1, GLRX5, HEPH, HFE, IREB2, QSOX1 and TFRC). Principal component analysis based on this signature is able to distinguish TICs from cancer cells in vitro and also Leukemia-initiating cells (LICs) from non-LICs in the mouse model of acute promyelocytic leukemia (APL). Majority of the described changes were also recapitulated in an alternative model represented by MCF7 cells resistant to tamoxifen (TAMR) that exhibit features of TICs. Our findings point to the critical importance of redox balance and iron metabolism-related genes and proteins in the context of cancer and TICs that could be potentially used for cancer diagnostics or therapy.
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MESH Headings
- Animals
- Antineoplastic Agents/pharmacology
- Biological Transport
- Breast Neoplasms/drug therapy
- Breast Neoplasms/enzymology
- Breast Neoplasms/genetics
- Breast Neoplasms/pathology
- Dose-Response Relationship, Drug
- Drug Resistance, Neoplasm
- Female
- Gene Expression Profiling
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Neoplastic
- Humans
- Iron/metabolism
- Iron Chelating Agents/pharmacology
- Leukemia, Promyelocytic, Acute/enzymology
- Leukemia, Promyelocytic, Acute/genetics
- MCF-7 Cells
- Male
- Mice, Transgenic
- Mitochondria/enzymology
- Neoplastic Stem Cells/drug effects
- Neoplastic Stem Cells/enzymology
- Neoplastic Stem Cells/pathology
- Phenotype
- Principal Component Analysis
- Prostatic Neoplasms/drug therapy
- Prostatic Neoplasms/enzymology
- Prostatic Neoplasms/genetics
- Prostatic Neoplasms/pathology
- Spheroids, Cellular
- Tamoxifen/pharmacology
- Transcriptome
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Affiliation(s)
- Zuzana Rychtarcikova
- Institute of Biotechnology, Czech Academy of Sciences, Prague, Czech Republic
- Charles University in Prague, Faculty of Pharmacy in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Sandra Lettlova
- Institute of Biotechnology, Czech Academy of Sciences, Prague, Czech Republic
- Charles University in Prague, Faculty of Sciences, Prague, Czech Republic
| | - Veronika Tomkova
- Institute of Biotechnology, Czech Academy of Sciences, Prague, Czech Republic
- Charles University in Prague, Faculty of Sciences, Prague, Czech Republic
| | - Vlasta Korenkova
- Institute of Biotechnology, Czech Academy of Sciences, Prague, Czech Republic
| | - Lucie Langerova
- Institute of Biotechnology, Czech Academy of Sciences, Prague, Czech Republic
| | - Ekaterina Simonova
- Institute of Biotechnology, Czech Academy of Sciences, Prague, Czech Republic
| | - Polina Zjablovskaja
- Institute of Molecular Genetics, Czech Academy of Sciences, Prague, Czech Republic
| | | | - Jiri Neuzil
- Institute of Biotechnology, Czech Academy of Sciences, Prague, Czech Republic
- School of Medical Science, Menzies Health Institute Queensland, Southport, Queensland, Australia
| | - Jaroslav Truksa
- Institute of Biotechnology, Czech Academy of Sciences, Prague, Czech Republic
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Lunetti P, Damiano F, De Benedetto G, Siculella L, Pennetta A, Muto L, Paradies E, Marobbio CMT, Dolce V, Capobianco L. Characterization of Human and Yeast Mitochondrial Glycine Carriers with Implications for Heme Biosynthesis and Anemia. J Biol Chem 2016; 291:19746-59. [PMID: 27476175 DOI: 10.1074/jbc.m116.736876] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Indexed: 01/19/2023] Open
Abstract
Heme is an essential molecule in many biological processes, such as transport and storage of oxygen and electron transfer as well as a structural component of hemoproteins. Defects of heme biosynthesis in developing erythroblasts have profound medical implications, as represented by sideroblastic anemia. The synthesis of heme requires the uptake of glycine into the mitochondrial matrix where glycine is condensed with succinyl coenzyme A to yield δ-aminolevulinic acid. Herein we describe the biochemical and molecular characterization of yeast Hem25p and human SLC25A38, providing evidence that they are mitochondrial carriers for glycine. In particular, the hem25Δ mutant manifests a defect in the biosynthesis of δ-aminolevulinic acid and displays reduced levels of downstream heme and mitochondrial cytochromes. The observed defects are rescued by complementation with yeast HEM25 or human SLC25A38 genes. Our results identify new proteins in the heme biosynthetic pathway and demonstrate that Hem25p and its human orthologue SLC25A38 are the main mitochondrial glycine transporters required for heme synthesis, providing definitive evidence of their previously proposed glycine transport function. Furthermore, our work may suggest new therapeutic approaches for the treatment of congenital sideroblastic anemia.
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Affiliation(s)
- Paola Lunetti
- From the Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Fabrizio Damiano
- From the Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Giuseppe De Benedetto
- Laboratory of Analytical and Isotopic Mass Spectrometry, Department of Cultural Heritage, University of Salento, 73100 Lecce, Italy
| | - Luisa Siculella
- From the Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Antonio Pennetta
- Laboratory of Analytical and Isotopic Mass Spectrometry, Department of Cultural Heritage, University of Salento, 73100 Lecce, Italy
| | - Luigina Muto
- Department of Pharmacy, Health, and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende (Cosenza), Italy
| | - Eleonora Paradies
- Consiglio Nazionale delle Ricerche, Institute of Biomembranes and Bioenergetics, 70125 Bari, Italy, and
| | - Carlo Marya Thomas Marobbio
- Department of Biosciences, Biotechnology, and Pharmacological Sciences, University of Bari, 70125 Bari, Italy
| | - Vincenza Dolce
- Department of Pharmacy, Health, and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende (Cosenza), Italy
| | - Loredana Capobianco
- From the Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
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30
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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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31
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Méndez M, Moreno‐Carralero M, Morado‐Arias M, Fernández‐Jiménez M, de la Iglesia Iñigo S, Morán‐Jiménez M. Sideroblastic anemia: functional study of two novel missense mutations in ALAS2. Mol Genet Genomic Med 2016; 4:273-82. [PMID: 27247955 PMCID: PMC4867561 DOI: 10.1002/mgg3.202] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 12/10/2015] [Accepted: 12/12/2015] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND X-linked sideroblastic anemia (XLSA) is a disorder characterized by decreased heme synthesis and mitochondrial iron overload with ringed sideroblasts in bone marrow. XLSA is caused by mutations in the erythroid-specific gene coding 5-aminolevulinate synthase (ALAS2). Anemia in XLSA is extremely variable, characteristically microcytic and hypochromic with poikilocytosis, and the red blood cell distribution width is increased and prominent dimorphism of the red cell population. Anemia in XLSA patients responds variably to supplementation with pyridoxine. METHODS AND RESULTS We report four patients with XLSA and three mutations in ALAS2: c.611G>A (p.Arg204Gln), c.1218G>T (p.Leu406Phe) and c.1499A>G (p.Tyr500Cys). The in silico predictions of three ALAS2 mutations and the functional consequences of two ALAS2 mutations were assessed. We performed in silico analysis of these mutations using ten different softwares, and all of them predicted that the p.Tyr500Cys mutation was deleterious. The in vitro prokaryotic expression showed that the p.Leu406Phe and p.Tyr500Cys mutations reduced the ALAS2 specific activity (SA) to 14% and 7% of the control value, respectively. CONCLUSION In view of the results obtained in this study, a clear relationship between genotype and phenotype cannot be established; clinical variability or severity of anemia may be influenced by allelic variants in other genes or transcription factors and environmental conditions.
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Affiliation(s)
- Manuel Méndez
- Instituto de InvestigaciónHospital 12 de OctubreMadridSpain
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Kardon JR, Yien YY, Huston NC, Branco DS, Hildick-Smith GJ, Rhee KY, Paw BH, Baker TA. Mitochondrial ClpX Activates a Key Enzyme for Heme Biosynthesis and Erythropoiesis. Cell 2016; 161:858-67. [PMID: 25957689 DOI: 10.1016/j.cell.2015.04.017] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 01/15/2015] [Accepted: 03/13/2015] [Indexed: 12/21/2022]
Abstract
The mitochondrion maintains and regulates its proteome with chaperones primarily inherited from its bacterial endosymbiont ancestor. Among these chaperones is the AAA+ unfoldase ClpX, an important regulator of prokaryotic physiology with poorly defined function in the eukaryotic mitochondrion. We observed phenotypic similarity in S. cerevisiae genetic interaction data between mitochondrial ClpX (mtClpX) and genes contributing to heme biosynthesis, an essential mitochondrial function. Metabolomic analysis revealed that 5-aminolevulinic acid (ALA), the first heme precursor, is 5-fold reduced in yeast lacking mtClpX activity and that total heme is reduced by half. mtClpX directly stimulates ALA synthase in vitro by catalyzing incorporation of its cofactor, pyridoxal phosphate. This activity is conserved in mammalian homologs; additionally, mtClpX depletion impairs vertebrate erythropoiesis, which requires massive upregulation of heme biosynthesis to supply hemoglobin. mtClpX, therefore, is a widely conserved stimulator of an essential biosynthetic pathway and uses a previously unrecognized mechanism for AAA+ unfoldases.
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Affiliation(s)
- Julia R Kardon
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Yvette Y Yien
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Nicholas C Huston
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Diana S Branco
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Gordon J Hildick-Smith
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Kyu Y Rhee
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY 10065, USA; Division of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Barry H Paw
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Division of Hematology-Oncology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Tania A Baker
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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Kawamura S, Yoshioka T, Mito N, Kishimoto N, Nakaoka M, Fantel AG. Mechanism of Developmental Effects in Rats Caused by an N-Phenylimide Herbicide: Transient Fetal Anemia and Sequelae during Mid-to-Late Gestation. ACTA ACUST UNITED AC 2016; 107:45-59. [PMID: 26865470 DOI: 10.1002/bdrb.21172] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 01/20/2016] [Indexed: 12/14/2022]
Abstract
BACKGROUND Rat developmental toxicity including embryolethality and teratogenicity (mainly ventricular septal defects [VSDs] and wavy ribs) was produced by an N-phenylimide herbicide that inhibits protoporphyrinogen oxidase (PPO) common to chlorophyll and heme biosynthesis. Major characteristics of the developmental toxicity included species difference between rats and rabbits, compound-specific difference among structurally similar herbicides, and sensitive period. Protoporphyrin accumulation in treated fetuses closely correlated with the major characteristics. Iron deposits in erythroblastic mitochondria and degeneration of erythroblasts were observed in treated rat fetuses. In this study we investigated fetal anemia and subsequent developmental effects in rats, and inhibition of PPO in rats, rabbits, and humans by the herbicides in vitro. METHODS Fetuses were treated on gestational day (GD) 12 and removed on GDs 13 through 20. All litters were examined externally. One half of litters were examined for blood and skeletal development, and the other half for interventricular foramen closure. Effects on PPO were determined in mitochondria from embryos and adult livers. RESULTS Fetal anemia in rats was evident on GDs 13 through 16. Subsequently, enlarged heart, delayed closure of the foramen, reduced serum protein, and retarded rib ossification were observed. In vitro PPO inhibition exhibited species- and compound-specific differences corresponding to the developmental toxicity. CONCLUSION We propose that developmental toxicity results from PPO inhibition in primitive erythroblasts, causing transient fetal anemia followed by death. Compensatory enlargement of the fetal heart results in failure of interventricular foramen closure and VSD. Reduced serum protein leads to delayed ossification and wavy ribs.
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Affiliation(s)
- Satoshi Kawamura
- Environmental Health Science Laboratory, Sumitomo Chemical Co. Ltd, Konohana-ku, Osaka, Japan
| | - Takafumi Yoshioka
- Environmental Health Science Laboratory, Sumitomo Chemical Co. Ltd, Konohana-ku, Osaka, Japan
| | - Nobuaki Mito
- Intellectual Property Department, Sumitomo Chemical Co. Ltd, Chuo-ku, Tokyo, Japan
| | - Noriyuki Kishimoto
- Environmental Health Science Laboratory, Sumitomo Chemical Co. Ltd, Konohana-ku, Osaka, Japan
| | - Masanao Nakaoka
- Environmental Health Science Laboratory, Sumitomo Chemical Co. Ltd, Konohana-ku, Osaka, Japan
| | - Alan G Fantel
- Department of Pediatrics, University of Washington, Seattle, Washington
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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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Mian SA, Rouault-Pierre K, Smith AE, Seidl T, Pizzitola I, Kizilors A, Kulasekararaj AG, Bonnet D, Mufti GJ. SF3B1 mutant MDS-initiating cells may arise from the haematopoietic stem cell compartment. Nat Commun 2015; 6:10004. [PMID: 26643973 PMCID: PMC4686651 DOI: 10.1038/ncomms10004] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 10/23/2015] [Indexed: 12/14/2022] Open
Abstract
Despite the recent evidence of the existence of myelodysplastic syndrome (MDS) stem cells in 5q-MDS patients, it is unclear whether haematopoietic stem cells (HSCs) could also be the initiating cells in other MDS subgroups. Here we demonstrate that SF3B1 mutation(s) in our cohort of MDS patients with ring sideroblasts can arise from CD34(+)CD38(-)CD45RA(-)CD90(+)CD49f(+) HSCs and is an initiating event in disease pathogenesis. Xenotransplantation of SF3B1 mutant HSCs leads to persistent long-term engraftment restricted to myeloid lineage. Moreover, genetically diverse evolving subclones of mutant SF3B1 exist in mice, indicating a branching multi-clonal as well as ancestral evolutionary paradigm. Subclonal evolution in mice is also seen in the clinical evolution in patients. Sequential sample analysis shows clonal evolution and selection of the malignant driving clone leading to AML transformation. In conclusion, our data show SF3B1 mutations can propagate from HSCs to myeloid progeny, therefore providing a therapeutic target.
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Affiliation(s)
- Syed A. Mian
- Department of Haematological Medicine, King's College London School of Medicine, London SE5 9NU, UK
| | - Kevin Rouault-Pierre
- Human Normal and Malignant Haematopoiesis Stem Cells and Their Microenvironment Laboratory, The Francis Crick Institute, Lincoln's Inn Fields Laboratories, London WC2A 3LY, UK
| | - Alexander E. Smith
- Department of Haematological Medicine, King's College London School of Medicine, London SE5 9NU, UK
- Department of Haematology, King's College Hospital, London SE5 9RS, UK
| | - Thomas Seidl
- Department of Haematological Medicine, King's College London School of Medicine, London SE5 9NU, UK
| | - Irene Pizzitola
- Human Normal and Malignant Haematopoiesis Stem Cells and Their Microenvironment Laboratory, The Francis Crick Institute, Lincoln's Inn Fields Laboratories, London WC2A 3LY, UK
| | - Aytug Kizilors
- Department of Haematology, King's College Hospital, London SE5 9RS, UK
| | - Austin G. Kulasekararaj
- Department of Haematological Medicine, King's College London School of Medicine, London SE5 9NU, UK
- Department of Haematology, King's College Hospital, London SE5 9RS, UK
| | - Dominique Bonnet
- Human Normal and Malignant Haematopoiesis Stem Cells and Their Microenvironment Laboratory, The Francis Crick Institute, Lincoln's Inn Fields Laboratories, London WC2A 3LY, UK
| | - Ghulam J. Mufti
- Department of Haematological Medicine, King's College London School of Medicine, London SE5 9NU, UK
- Department of Haematology, King's College Hospital, London SE5 9RS, UK
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Camaschella C, Nai A. Ineffective erythropoiesis and regulation of iron status in iron loading anaemias. Br J Haematol 2015; 172:512-23. [PMID: 26491866 DOI: 10.1111/bjh.13820] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The definition 'iron loading anaemias' encompasses a group of inherited and acquired anaemias characterized by ineffective erythropoiesis, low hepcidin levels, excessive iron absorption and secondary iron overload. Non-transfusion-dependent β-thalassaemia is the paradigmatic example of these conditions that include dyserythropoietic and sideroblastic anaemias and some forms of myelodysplasia. Interrupting the vicious cycle between ineffective erythropoiesis and iron overload may be of therapeutic benefit in all these diseases. Induction of iron restriction by means of transferrin infusions, minihepcidins or manipulation of the hepcidin pathway prevents iron overload, redistributes iron from parenchymal cells to macrophage stores and partially controls anaemia in β-thalassaemic mice. Inhibition of ineffective erythropoiesis by activin ligand traps improves anaemia and iron overload in the same models. Targeting iron loading or ineffective erythropoiesis shows promise in preclinical studies; activin ligand traps are in clinical trials with promising results and may be useful in patients with ineffective erythropoiesis.
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Affiliation(s)
- Clara Camaschella
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Vita Salute University, Milano, Italy
| | - Antonella Nai
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Vita Salute University, Milano, Italy
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Biology of Heme in Mammalian Erythroid Cells and Related Disorders. BIOMED RESEARCH INTERNATIONAL 2015; 2015:278536. [PMID: 26557657 PMCID: PMC4628764 DOI: 10.1155/2015/278536] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Accepted: 06/14/2015] [Indexed: 01/19/2023]
Abstract
Heme is a prosthetic group comprising ferrous iron (Fe(2+)) and protoporphyrin IX and is an essential cofactor in various biological processes such as oxygen transport (hemoglobin) and storage (myoglobin) and electron transfer (respiratory cytochromes) in addition to its role as a structural component of hemoproteins. Heme biosynthesis is induced during erythroid differentiation and is coordinated with the expression of genes involved in globin formation and iron acquisition/transport. However, erythroid and nonerythroid cells exhibit distinct differences in the heme biosynthetic pathway regulation. Defects of heme biosynthesis in developing erythroblasts can have profound medical implications, as represented by sideroblastic anemia. This review will focus on the biology of heme in mammalian erythroid cells, including the heme biosynthetic pathway as well as the regulatory role of heme and human disorders that arise from defective heme synthesis.
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Patnaik MM, Tefferi A. Refractory anemia with ring sideroblasts and RARS with thrombocytosis. Am J Hematol 2015; 90:549-59. [PMID: 25899435 DOI: 10.1002/ajh.24038] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 04/17/2015] [Indexed: 12/25/2022]
Abstract
DISEASE OVERVIEW Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include refractory anemia with ring sideroblasts (RARS) and RARS with thrombocytosis (RARS-T). DIAGNOSIS RARS is a lower risk myelodysplastic syndrome (MDS) with dysplasia limited to the erythroid lineage, <5% bone marrow (BM) blasts and ≥15% BM RS. RARS-T is a provisional entity in the MDS/MPN (myeloproliferative neoplasm) overlap syndromes, with diagnostic features of RARS, along with a platelet count ≥450 × 10(9)/L and large atypical megakaryocytes similar to those observed in BCR-ABL1 negative MPN. Mutations and Karyotype: Mutations in the SF3B1 gene are seen in ≥80% of patients with RARS and RARS-T, and strongly correlate with the presence of BM RS; RARS-T patients have additional mutations such as, JAK2V617F (∼60%), MPL (<5%), and CALR (<5%). Cytogenetic abnormalities are uncommon in both RARS and RARS-T. RISK STRATIFICATION Most patients with RARS are stratified into lower risk groups by the International Prognostic Scoring System (IPSS) for MDS and the revised IPSS. Disease outcome in RARS-T is better than that of RARS, but worse than that of essential thrombocytosis. Both RARS and RARS-T have a low risk of leukemic transformation. TREATMENT Anemia and iron overload are complications in both diseases and are managed similar to lower risk MDS. Aspirin therapy is reasonable in RARS-T, especially in the presence of JAK2V617F, but the value of platelet-lowering drugs is uncertain. Case reports of RARS-T therapy with lenalidomide warrant additional studies.
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Affiliation(s)
- Mrinal M. Patnaik
- Division of Hematology, Department of Internal Medicine; Mayo Clinic; Rochester Minnesota
| | - Ayalew Tefferi
- Division of Hematology, Department of Internal Medicine; Mayo Clinic; Rochester Minnesota
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Abstract
The practice of intravenous iron supplementation has grown as nephrologists have gradually moved away from the liberal use of erythropoiesis-stimulating agents as the main treatment for the anemia of CKD. This approach, together with the introduction of large-dose iron preparations, raises the future specter of inadvertent iatrogenic iron toxicity. Concerns have been raised in original studies and reviews about cardiac complications and severe infections that result from long-term intravenous iron supplementation. Regarding the iron preparations specifically, even though all the currently available preparations appear to be relatively safe in the short term, little is known regarding their long-term safety. In this review we summarize current knowledge of iron metabolism with an emphasis on the sources and potentially harmful effects of labile iron, highlight the approaches to identifying labile iron in pharmaceutical preparations and body fluids and its potential toxic role as a pathogenic factor in the complications of CKD, and propose methods for its early detection in at-risk patients.
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Affiliation(s)
- Itzchak Slotki
- Division of Adult Nephrology, Shaare Zedek Medical Center and Hadassah Hebrew University of Jerusalem, Jerusalem, Israel; and
| | - Zvi Ioav Cabantchik
- Department of Biological Chemistry, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
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Chiabrando D, Mercurio S, Tolosano E. Heme and erythropoieis: more than a structural role. Haematologica 2015; 99:973-83. [PMID: 24881043 DOI: 10.3324/haematol.2013.091991] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Erythropoiesis is the biological process that consumes the highest amount of body iron for heme synthesis. Heme synthesis in erythroid cells is finely coordinated with that of alpha (α) and beta (β)-globin, resulting in the production of hemoglobin, a tetramer of 2α- and 2β-globin chains, and heme as the prosthetic group. Heme is not only the structural component of hemoglobin, but it plays multiple regulatory roles during the differentiation of erythroid precursors since it controls its own synthesis and regulates the expression of several erythroid-specific genes. Heme is synthesized in developing erythroid progenitors by the stage of proerythroblast, through a series of eight enzymatic reactions divided between mitochondria and cytosol. Defects of heme synthesis in the erythroid lineage result in sideroblastic anemias, characterized by microcytic anemia associated to mitochondrial iron overload, or in erythropoietic porphyrias, characterized by porphyrin deposition in erythroid cells. Here, we focus on the heme biosynthetic pathway and on human erythroid disorders due to defective heme synthesis. The regulatory role of heme during erythroid differentiation is discussed as well as the heme-mediated regulatory mechanisms that allow the orchestration of the adaptive cell response to heme deficiency.
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Affiliation(s)
- Deborah Chiabrando
- Department of Molecular Biotechnology and Health Sciences and Molecular Biotechnology Center, University of Torino, Italy
| | - Sonia Mercurio
- Department of Molecular Biotechnology and Health Sciences and Molecular Biotechnology Center, University of Torino, Italy
| | - Emanuela Tolosano
- Department of Molecular Biotechnology and Health Sciences and Molecular Biotechnology Center, University of Torino, Italy
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Rollón N, Fernández-Jiménez MC, Moreno-Carralero MI, Murga-Fernández MJ, Morán-Jiménez MJ. Microcytic anemia in a pregnant woman: beyond iron deficiency. Int J Hematol 2014; 101:514-9. [PMID: 25547425 DOI: 10.1007/s12185-014-1723-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 12/09/2014] [Accepted: 12/11/2014] [Indexed: 01/19/2023]
Abstract
Sideroblastic anemias are a heterogeneous group of disorders characterized by anemia of varying severity and the presence of ringed sideroblasts in bone marrow. The most common form of inherited sideroblastic anemia is X-linked sideroblastic anemia (XLSA). In many XLSA patients, anemia responds variably to supplementation with pyridoxine (vitamin B6). We describe the case of a pregnant female with XLSA who had a novel mutation on the ALAS2 gene (c.1218G > T, p.Leu406Phe). Oral chelation therapy was contraindicated and high-dose vitamin B6 would have possible side effects in pregnancy. Serum hepcidin level was very low, indicating increased absorption of iron secondary to ineffective erythropoiesis. Therapy was begun with a low dose of pyridoxine that was increased post-partum. The patient's liver showed moderate iron deposits. During a subsequent 3-month period of pyridoxine supplementation, serum ferritin level and transferrin saturation decreased, hemoglobin content and serum hepcidin level normalized, and morphologic red cell abnormalities improved markedly. The patient responded well to treatment, showing the pyridoxine responsiveness of this novel ALAS2 mutation. The baby girl had the same mutation heterozygously, and although she was neither anemic nor showed abnormalities in a peripheral blood smear, she had a mild increment in RDW and her condition is now being followed.
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Affiliation(s)
- Noelia Rollón
- Department of Hematology, Complejo Hospitalario de Toledo, Hospital Virgen de la Salud, Avenida de Barber, 30, 45004, Toledo, Spain,
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Wong WS, Wong HF, Cheng CK, Chang KO, Chan NPH, Ng MHL, Wong KF. Congenital sideroblastic anaemia with a novel frameshift mutation inSLC25A38. J Clin Pathol 2014; 68:249-51. [DOI: 10.1136/jclinpath-2014-202211] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Maio N, Rouault TA. Iron-sulfur cluster biogenesis in mammalian cells: New insights into the molecular mechanisms of cluster delivery. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:1493-512. [PMID: 25245479 DOI: 10.1016/j.bbamcr.2014.09.009] [Citation(s) in RCA: 155] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 09/07/2014] [Indexed: 01/19/2023]
Abstract
Iron-sulfur (Fe-S) clusters are ancient, ubiquitous cofactors composed of iron and inorganic sulfur. The combination of the chemical reactivity of iron and sulfur, together with many variations of cluster composition, oxidation states and protein environments, enables Fe-S clusters to participate in numerous biological processes. Fe-S clusters are essential to redox catalysis in nitrogen fixation, mitochondrial respiration and photosynthesis, to regulatory sensing in key metabolic pathways (i.e. cellular iron homeostasis and oxidative stress response), and to the replication and maintenance of the nuclear genome. Fe-S cluster biogenesis is a multistep process that involves a complex sequence of catalyzed protein-protein interactions and coupled conformational changes between the components of several dedicated multimeric complexes. Intensive studies of the assembly process have clarified key points in the biogenesis of Fe-S proteins. However several critical questions still remain, such as: what is the role of frataxin? Why do some defects of Fe-S cluster biogenesis cause mitochondrial iron overload? How are specific Fe-S recipient proteins recognized in the process of Fe-S transfer? This review focuses on the basic steps of Fe-S cluster biogenesis, drawing attention to recent advances achieved on the identification of molecular features that guide selection of specific subsets of nascent Fe-S recipients by the cochaperone HSC20. Additionally, it outlines the distinctive phenotypes of human diseases due to mutations in the components of the basic pathway. This article is part of a Special Issue entitled: Fe/S proteins: Analysis, structure, function, biogenesis and diseases.
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Affiliation(s)
- Nunziata Maio
- Molecular Medicine Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, 9000 Rockville Pike, 20892 Bethesda, MD, USA
| | - Tracey A Rouault
- Molecular Medicine Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, 9000 Rockville Pike, 20892 Bethesda, MD, USA.
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44
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Delette C, Ferret Y, Claisse JF, Guiheneuf E. Refractory anaemia with ring sideroblasts and monosomy 7 in a 10-year-old child. Int J Hematol 2014; 100:521-2. [PMID: 25227184 DOI: 10.1007/s12185-014-1671-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 09/03/2014] [Accepted: 09/03/2014] [Indexed: 11/29/2022]
Affiliation(s)
- Caroline Delette
- Department of Haematology, University Hospital of Amiens, Amiens, France
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45
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Panch SR, Yau YY, West K, Diggs K, Sweigart T, Leitman SF. Initial serum ferritin predicts number of therapeutic phlebotomies to iron depletion in secondary iron overload. Transfusion 2014; 55:611-22. [PMID: 25209879 DOI: 10.1111/trf.12854] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Revised: 07/26/2014] [Accepted: 07/28/2014] [Indexed: 02/06/2023]
Abstract
BACKGROUND Therapeutic phlebotomy is increasingly used in patients with transfusional siderosis to mitigate organ injury associated with iron overload (IO). Laboratory response variables and therapy duration are not well characterized in such patients. STUDY DESIGN AND METHODS We retrospectively evaluated 99 consecutive patients undergoing therapeutic phlebotomy for either transfusional IO (TIO, n = 88; 76% had undergone hematopoietic transplantation) or nontransfusional indications (hyperferritinemia or erythrocytosis; n = 11). Complete blood cell count, serum ferritin (SF), transferrin saturation, and transaminases were measured serially. Phlebotomy goal was an SF level of less than 300 μg/L. RESULTS Mean SF levels before phlebotomy among TIO and nontransfusional subjects were 3093 and 396 μg/L, respectively. Transfusion burden in the TIO group was 94 ± 108 (mean ± SD) RBC units; approximately half completed therapy with 24 ± 23 phlebotomies (range, 1-103). One-third were lost to follow-up. Overall, 15% had mild adverse effects, including headache, nausea, and dizziness, mainly during first phlebotomy. Prior transfusion burden correlated poorly with initial ferritin and total number of phlebotomies to target in the TIO group. However, number of phlebotomies to target was strongly correlated with initial SF (R(2) = 0.8; p < 0.0001) in both TIO and nontransfusional groups. ALT decreased significantly with serial phlebotomy in all groups (mean initial and final values, 61 and 39 U/L; p = 0.03). CONCLUSIONS Initial SF but not transfusion burden predicted number of phlebotomies to target in patients with TIO. Despite good treatment tolerance, significant losses to follow-up were noted. Providing patients with an estimated phlebotomy number and follow-up duration, and thus a finite endpoint, may improve compliance. Hepatic function improved with iron offloading.
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Affiliation(s)
- Sandhya R Panch
- Hematology/Transfusion Medicine, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
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46
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El Sayed SM, Abou-Taleb A, Mahmoud HS, Baghdadi H, Maria RA, Ahmed NS, Nabo MMH. Percutaneous excretion of iron and ferritin (through Al-hijamah) as a novel treatment for iron overload in beta-thalassemia major, hemochromatosis and sideroblastic anemia. Med Hypotheses 2014; 83:238-46. [PMID: 24857772 DOI: 10.1016/j.mehy.2014.04.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 09/25/2013] [Accepted: 04/01/2014] [Indexed: 11/24/2022]
Abstract
Iron overload is a big challenge when treating thalassemia (TM), hemochromatosis and sideroblastic anemia. It persists even after cure of TM with bone marrow transplantation. Iron overload results from increased iron absorption and repeated blood transfusions causing increased iron in plasma and interstitial fluids. Iron deposition in tissues e.g. heart, liver, endocrine glands and others leads to tissue damage and organ dysfunction. Iron chelation therapy and phlebotomy for iron overload have treatment difficulties, side effects and contraindications. As mean iron level in skin of TM patients increases by more than 200%, percutaneous iron excretion may be beneficial. Wet cupping therapy (WCT) is a simple, safe and economic treatment. WCT is a familiar treatment modality in some European countries and in Chinese hospitals in treating different diseases. WCT was reported to clear both blood plasma and interstitial spaces from causative pathological substances (CPS). Standard WCT method is Al-hijamah (cupping, puncturing and cupping, CPC) method of WCT that was reported to clear blood and interstitial fluids better than the traditional WCT (puncturing and cupping method, PC method of WCT). In other word, traditional WCT may be described as scarification and suction method (double S technique), while Al-hijamah may be described as suction, scarification and suction method (triple S technique). Al-hijamah is a more comprehensive treatment modality that includes all steps and therapeutic benefits of traditional dry cupping therapy and WCT altogether according to the evidence-based Taibah mechanism (Taibah theory). During the first cupping step of Al-hijamah, a fluid mixture is collected inside skin uplifting due to the effect of negative pressure inside sucking cups. This fluid mixture contains collected interstitial fluids with CPS (iron, ferritin and hemolyzed RBCs in thalassemia), filtered fluids (from blood capillaries) with iron and hemolyzed blood cells (hemolyzed RBCs, WBCs and platelets). That fluid mixture does not contain intact blood cells (having diameters in microns) that are too big to pass through pores of skin capillaries (6-12nm in diameter) and cannot be filtered. Puncturing skin upliftings and applying second cupping step excrete collected fluids. Skin scarifications (shartat mihjam in Arabic) should be small, superficial (0.1mm in depth), short (1-2mm in length), multiple, evenly distributed and confined to skin upliftings. Sucking pressure inside cups (-150 to -420mmHg) applied to skin is transmitted to around skin capillaries to be added to capillary hydrostatic pressure (-33mmHg at arterial end of capillaries and -13mmHg at venous end of capillaries) against capillary osmotic pressure (+20mmHg). This creates a pressure gradient and a traction force across skin and capillaries and increases filtration at arterial end of capillaries at net pressure of -163 to -433mmHg and at venous end of capillaries at net pressure of -143 to -413mmHg resulting in clearance of blood from CPS (iron, ferritin and hemolyzed blood cells). Net filtration pressure at renal glomeruli is 10mmHg i.e. Al-hijamah exerts a more pressure-dependent filtration than renal glomeruli. Al-hijamah may benefit patients through inducing negative iron balance. Interestingly, Al-hijamah was reported to decrease serum ferritin significantly (by about 22%) in healthy subjects while excessive traditional WCT was reported to cause iron deficiency anemia. Al-hijamah is a highly recommended treatment in prophetic medicine. In conclusion, Al-hijamah may be a promising adjuvant treatment for iron overload in TM, hemochromatosis and sideroblastic anemia.
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Affiliation(s)
- Salah Mohamed El Sayed
- Department of Clinical Biochemistry and Molecular Medicine, Taibah Faculty of Medicine, Taibah University, Al-Madinah Al-Munawwarah, Saudi Arabia. Department of Medical Biochemistry, Sohag Faculty of Medicine, Sohag University, Egypt
| | - Ashraf Abou-Taleb
- Department of Pediatrics, Sohag Faculty of Medicine, Sohag University, Egypt
| | - Hany Salah Mahmoud
- World Federation of Alternative and Complementary Medicine, Cairo Regional Headquarter, Cairo, Egypt
| | - Hussam Baghdadi
- Department of Clinical Biochemistry and Molecular Medicine, Taibah Faculty of Medicine, Taibah University, Al-Madinah Al-Munawwarah, Kingdom of Saudi Arabia
| | - Reham A Maria
- Department of Clinical Biochemistry and Molecular Medicine, Taibah Faculty of Medicine, Taibah University, Al-Madinah Al-Munawwarah, Kingdom of Saudi Arabia; Department of Medical Biochemistry, Tanta Faulty of Medicine, Tanta University, Egypt
| | - Nagwa Sayed Ahmed
- Department of Medical Biochemistry, Sohag Faculty of Medicine, Sohag University, Egypt
| | - Manal Mohamed Helmy Nabo
- Department of Pediatrics, Sohag Teaching Hospital, Sohag, Egypt; Division of Pediatric Cardiology, Department of Pediatrics, Maternity and Children Hospital, King Abdullah Medical City, Al-Madinah Al-Munawwarah, Kingdom of Saudi Arabia
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Anzovino A, Lane DJR, Huang MLH, Richardson DR. Fixing frataxin: 'ironing out' the metabolic defect in Friedreich's ataxia. Br J Pharmacol 2014; 171:2174-90. [PMID: 24138602 PMCID: PMC3976629 DOI: 10.1111/bph.12470] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 09/17/2013] [Accepted: 10/07/2013] [Indexed: 12/14/2022] Open
Abstract
The metabolically active and redox-active mitochondrion appears to play a major role in the cellular metabolism of the transition metal, iron. Frataxin, a mitochondrial matrix protein, has been identified as playing a key role in the iron metabolism of this organelle due to its iron-binding properties and is known to be essential for iron-sulphur cluster formation. However, the precise function of frataxin remains elusive. The decrease in frataxin expression, as seen in the inherited disorder Friedreich's ataxia, markedly alters cellular and mitochondrial iron metabolism in both the mitochondrion and the cell. The resulting dysregulation of iron trafficking damages affects tissues leading to neuro- and cardiodegeneration. This disease underscores the importance of iron homeostasis in the redox-active environment of the mitochondrion and the molecular players involved. Unravelling the mechanisms of altered iron metabolism in Friedreich's ataxia will help elucidate a biochemical function for frataxin. Consequently, this will enable the development of more effective and rationally designed treatments. This review will focus on the emerging function of frataxin in relation to the observed alterations in mitochondrial iron metabolism in Friedreich's ataxia. Tissue-specific alterations due to frataxin loss will also be discussed, as well as current and emerging therapeutic strategies.
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Affiliation(s)
- A Anzovino
- Molecular Pharmacology and Pathology Program, Department of Pathology and Bosch Institute, University of SydneySydney, NSW, Australia
| | - D J R Lane
- Molecular Pharmacology and Pathology Program, Department of Pathology and Bosch Institute, University of SydneySydney, NSW, Australia
| | | | - D R Richardson
- Correspondence Professor D R Richardson, Molecular Pharmacology and Pathology Program, Department of Pathology and Bosch Institute, University of Sydney, Sydney, NSW 2006, Australia. E-mail:
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Practice guidelines for the diagnosis and management of microcytic anemias due to genetic disorders of iron metabolism or heme synthesis. Blood 2014; 123:3873-86; quiz 4005. [PMID: 24665134 DOI: 10.1182/blood-2014-01-548776] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
During recent years, our understanding of the pathogenesis of inherited microcytic anemias has gained from the identification of several genes and proteins involved in systemic and cellular iron metabolism and heme syntheses. Numerous case reports illustrate that the implementation of these novel molecular discoveries in clinical practice has increased our understanding of the presentation, diagnosis, and management of these diseases. Integration of these insights into daily clinical practice will reduce delays in establishing a proper diagnosis, invasive and/or costly diagnostic tests, and unnecessary or even detrimental treatments. To assist the clinician, we developed evidence-based multidisciplinary guidelines on the management of rare microcytic anemias due to genetic disorders of iron metabolism and heme synthesis. These genetic disorders may present at all ages, and therefore these guidelines are relevant for pediatricians as well as clinicians who treat adults. This article summarizes these clinical practice guidelines and includes background on pathogenesis, conclusions, and recommendations and a diagnostic flowchart to facilitate using these guidelines in the clinical setting.
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49
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Cabantchik ZI. Labile iron in cells and body fluids: physiology, pathology, and pharmacology. Front Pharmacol 2014; 5:45. [PMID: 24659969 PMCID: PMC3952030 DOI: 10.3389/fphar.2014.00045] [Citation(s) in RCA: 206] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 02/26/2014] [Indexed: 12/25/2022] Open
Abstract
In living systems iron appears predominantly associated with proteins, but can also be detected in forms referred as labile iron, which denotes the combined redox properties of iron and its amenability to exchange between ligands, including chelators. The labile cell iron (LCI) composition varies with metal concentration and substances with chelating groups but also with pH and the medium redox potential. Although physiologically in the lower μM range, LCI plays a key role in cell iron economy as cross-roads of metabolic pathways. LCI levels are continually regulated by an iron-responsive machinery that balances iron uptake versus deposition into ferritin. However, LCI rises aberrantly in some cell types due to faulty cell utilization pathways or infiltration by pathological iron forms that are found in hemosiderotic plasma. As LCI attains pathological levels, it can catalyze reactive O species (ROS) formation that, at particular threshold, can surpass cellular anti-oxidant capacities and seriously damage its constituents. While in normal plasma and interstitial fluids, virtually all iron is securely carried by circulating transferrin (Tf; that renders iron essentially non-labile), in systemic iron overload (IO), the total plasma iron binding capacity is often surpassed by a massive iron influx from hyperabsorptive gut or from erythrocyte overburdened spleen and/or liver. As plasma Tf approaches iron saturation, labile plasma iron (LPI) emerges in forms that can infiltrate cells by unregulated routes and raise LCI to toxic levels. Despite the limited knowledge available on LPI speciation in different types and degrees of IO, LPI measurements can be and are in fact used for identifying systemic IO and for initiating/adjusting chelation regimens to attain full-day LPI protection. A recent application of labile iron assay is the detection of labile components in intravenous iron formulations per se as well as in plasma (LPI) following parenteral iron administration.
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Affiliation(s)
- Zvi Ioav Cabantchik
- Department of Biological Chemistry, Institute of Life Sciences, Hebrew University of Jerusalem Jerusalem, Israel
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Koury MJ. Abnormal erythropoiesis and the pathophysiology of chronic anemia. Blood Rev 2014; 28:49-66. [PMID: 24560123 DOI: 10.1016/j.blre.2014.01.002] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 01/17/2014] [Indexed: 12/14/2022]
Abstract
Erythropoiesis, the bone marrow production of erythrocytes by the proliferation and differentiation of hematopoietic cells, replaces the daily loss of 1% of circulating erythrocytes that are senescent. This daily output increases dramatically with hemolysis or hemorrhage. When erythrocyte production rate of erythrocytes is less than the rate of loss, chronic anemia develops. Normal erythropoiesis and specific abnormalities of erythropoiesis that cause chronic anemia are considered during three periods of differentiation: a) multilineage and pre-erythropoietin-dependent hematopoietic progenitors, b) erythropoietin-dependent progenitor cells, and c) terminally differentiating erythroblasts. These erythropoietic abnormalities are discussed in terms of their pathophysiological effects on the bone marrow cells and the resultant changes that can be detected in the peripheral blood using a clinical laboratory test, the complete blood count.
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Affiliation(s)
- Mark J Koury
- Division of Hematology/Oncology, Vanderbilt University and Veterans Affairs Tennessee Valley Healthcare System, 777 Preston Research Building, Nashville, TN 37232, USA.
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