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Prakash C, Mangus H, Yan Y, Yang H, Iyer V. An innovative phase I study in healthy subjects to determine the mass balance, elimination, metabolism, and absolute bioavailability of mitapivat. Clin Transl Sci 2023; 16:2021-2032. [PMID: 37596712 PMCID: PMC10582659 DOI: 10.1111/cts.13609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 07/08/2023] [Accepted: 07/28/2023] [Indexed: 08/20/2023] Open
Abstract
Mitapivat, a first-in-class, oral, small-molecule, allosteric activator of the red blood cell-specific form of pyruvate kinase (PKR), was approved for the treatment of hemolytic anemia in adults with pyruvate kinase (PK) deficiency. In this phase I mass balance study in healthy males, we administered a single ~120 mg oral dose of [14 C]mitapivat and a concomitant intravenous ~0.1 mg microdose of [13 C6 ]mitapivat. We determined (1) the routes of total radioactivity excretion, including the mass balance of total radioactivity in urine and feces; (2) the pharmacokinetics of mitapivat and [13 C6 ]mitapivat in plasma and total radioactivity in whole blood and plasma; (3) the absolute oral bioavailability of mitapivat; and (4) the metabolite profiles in plasma and excreta. Mean recovery of the radioactive dose was 89.1% (49.6% in urine and 39.6% in feces). [14 C]Mitapivat was rapidly absorbed and extensively metabolized as <4% of the total radioactive dose was excreted unaltered in urine and feces. Mean absolute oral bioavailability was 72.7%. A total of 17 metabolites were identified. Mitapivat accounted for 57% and 34% of plasma radioactivity in AUC0-24 and AUC0-72 pooled samples, respectively. The remaining radioactivity was attributable to several metabolites, each representing <10% of the total radioactivity in pooled samples; none were disproportionate metabolites as defined by the US Food and Drug Administration and International Conference on Harmonisation M3 guidelines. Metabolite structures suggest that the primary metabolic pathways for [14 C]mitapivat in humans include N-dealkylation of the cyclopropylmethyl moiety, oxygenation of the quinoline-8-sulfonamide, oxidation/unsaturation, scission of the piperazine moiety, and amide hydrolysis.
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Affiliation(s)
| | | | - Yan Yan
- Agios PharmaceuticalsCambridgeMassachusettsUSA
| | - Hua Yang
- Agios PharmaceuticalsCambridgeMassachusettsUSA
| | - Varsha Iyer
- Agios PharmaceuticalsCambridgeMassachusettsUSA
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2
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Dongerdiye R, Bokde M, More TA, Saptarshi A, Devendra R, Chiddarwar A, Warang P, Kedar P. Targeted next-generation sequencing identifies eighteen novel mutations expanding the molecular and clinical spectrum of PKLR gene disorders in the Indian population. Ann Hematol 2023; 102:1029-1036. [PMID: 36892591 DOI: 10.1007/s00277-023-05152-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 02/23/2023] [Indexed: 03/10/2023]
Abstract
Pyruvate kinase deficiency (PKD) is an autosomal recessive condition, caused due to homozygous or compound heterozygous mutation in the PKLR gene resulting in non-spherocytic hereditary hemolytic anemia. Clinical manifestations in PKD patients vary from moderate to severe lifelong hemolytic anemia either requiring neonatal exchange transfusion or blood transfusion support. Measuring PK enzyme activity is the gold standard approach for diagnosis but residual activity must be related to the increased reticulocyte count. The confirmatory diagnosis is provided by PKLR gene sequencing by conventional as well as targeted next-generation sequencing involving genes associated with enzymopathies, membranopathies, hemoglobinopathies, and bone marrow failure disorders. In this study, we report the mutational landscape of 45 unrelated PK deficiency cases from India. The genetic sequencing of PKLR revealed 40 variants comprising 34 Missense Mutations (MM), 2 Nonsense Mutations (NM), 1 Splice site, 1 Intronic, 1 Insertion, and 1 Large Base Deletion. The 17 novel variants identified in this study are A115E, R116P, A423G, K313I, E315G, E318K, L327P, M377L, A423E, R449G, H507Q, E538K, G563S, c.507 + 1 G > C, c.801_802 ins A (p.Asp268ArgfsTer48), IVS9dsA-T + 3, and one large base deletion. In combination with previous reports on PK deficiency, we suggest c.880G > A, c.943G > A, c.994G > A, c.1456C > T, c.1529G > A are the most frequently observed mutations in India. This study expands the phenotypic and molecular spectrum of PKLR gene disorders and also emphasizes the importance of combining both targeted next-generation sequencing with bioinformatics analysis and detailed clinical evaluation to elaborate a more accurate diagnosis and correct diagnosis for transfusion dependant hemolytic anemia in a cohort of the Indian population.
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Affiliation(s)
- Rashmi Dongerdiye
- Department of Haematogenetics, ICMR-National Institute of Immunohematology, 13th Floor, NMS Building, King Edward Memorial (KEM) Hospital Campus, Parel, 400012, Mumbai, India
| | - Meghana Bokde
- Department of Haematogenetics, ICMR-National Institute of Immunohematology, 13th Floor, NMS Building, King Edward Memorial (KEM) Hospital Campus, Parel, 400012, Mumbai, India
| | - Tejashree Anil More
- Department of Haematogenetics, ICMR-National Institute of Immunohematology, 13th Floor, NMS Building, King Edward Memorial (KEM) Hospital Campus, Parel, 400012, Mumbai, India
| | - Arati Saptarshi
- Department of Haematogenetics, ICMR-National Institute of Immunohematology, 13th Floor, NMS Building, King Edward Memorial (KEM) Hospital Campus, Parel, 400012, Mumbai, India
| | - Rati Devendra
- Department of Haematogenetics, ICMR-National Institute of Immunohematology, 13th Floor, NMS Building, King Edward Memorial (KEM) Hospital Campus, Parel, 400012, Mumbai, India
| | - Ashish Chiddarwar
- Department of Haematogenetics, ICMR-National Institute of Immunohematology, 13th Floor, NMS Building, King Edward Memorial (KEM) Hospital Campus, Parel, 400012, Mumbai, India
| | - Prashant Warang
- Department of Haematogenetics, ICMR-National Institute of Immunohematology, 13th Floor, NMS Building, King Edward Memorial (KEM) Hospital Campus, Parel, 400012, Mumbai, India
| | - Prabhakar Kedar
- Department of Haematogenetics, ICMR-National Institute of Immunohematology, 13th Floor, NMS Building, King Edward Memorial (KEM) Hospital Campus, Parel, 400012, Mumbai, India.
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3
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Morado M, Villegas AM, de la Iglesia S, Martínez-Nieto J, Del Orbe Barreto R, Beneitez D, Salido E. [Consensus document for the diagnosis and treatment of pyruvate kinase deficiency]. Med Clin (Barc) 2021; 157:253.e1-253.e8. [PMID: 33431182 DOI: 10.1016/j.medcli.2020.10.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 10/09/2020] [Accepted: 10/14/2020] [Indexed: 01/19/2023]
Abstract
Pyruvate kinase (PK) deficiency is the second most frequent enzymopathy and the most common cause of chronic hereditary non-spherocytic haemolytic anaemia. Its global prevalence is underestimated due to low clinical suspicion of mild cases, associated with difficulties in the performance and interpretation of PK enzymatic activity assays. With the advent of next generation sequencing techniques, a better diagnostic approach is achieved. Treatment remains based on red blood cell transfusions and splenectomy, with special attention to iron overload, not only in transfusion-dependent patients. Nowadays, allogeneic hematopoietic stem cell transplantation is the only curative treatment, recommended only in selected cases of severely affected patients with an HLA-identical donor. Novel pharmacological and gene therapies are in clinical trials, with promising results. In this article, the Spanish Erythropathology Group reviews the current situation of PK deficiency, paying special attention to the usefulness of different diagnostic techniques and to actual and emerging treatments.
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Affiliation(s)
- Marta Morado
- Servicio de Hematología y Hemoterapia, Hospital Universitario La Paz, Madrid, España.
| | - Ana María Villegas
- Servicio de Hematología y Hemoterapia, Hospital Universitario Clínico San Carlos, Madrid, España
| | - Silvia de la Iglesia
- Servicio de Hematología y Hemoterapia, Hospital Universitario Doctor Negrín, Las Palmas de Gran Canaria, España
| | - Jorge Martínez-Nieto
- Servicio de Hematología y Hemoterapia, Hospital Universitario Clínico San Carlos, Madrid, España
| | - Rafael Del Orbe Barreto
- Servicio de Hematología y Hemoterapia, Hospital Universitario de Cruces, Barakaldo, Vizcaya, España
| | - David Beneitez
- Servicio de Hematología y Hemoterapia, Hospital Universitario Vall d'Hebron, Barcelona, España
| | - Eduardo Salido
- Servicio de Hematología y Hemoterapia, Hospital Universitario Virgen de la Arrixaca, Murcia, España
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4
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Proteomic Characterization of Colorectal Cancer Tissue from Patients Identifies Novel Putative Protein Biomarkers. Curr Issues Mol Biol 2021; 43:1043-1056. [PMID: 34563043 PMCID: PMC8929084 DOI: 10.3390/cimb43020074] [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: 08/21/2021] [Revised: 08/29/2021] [Accepted: 08/30/2021] [Indexed: 12/11/2022] Open
Abstract
Colorectal cancer (CRC) is one of the leading causes of cancer-related death over the world. There is a great need for biomarkers capable of early detection and as targets for treatment. Differential protein expression was investigated with two-dimensional gel electrophoresis (2D-PAGE) followed by identification with liquid chromatography–tandem mass spectrometry (LC-MS/MS) in CRC patient tissue from (i) the peripheral part of the tumor, (ii) the central part of the tumor as well as from (iii) a non-involved part of the colorectal tissue. The expression patterns of six identified proteins were further evaluated by one-dimensional Western blot (1D-WB) analysis of the CRC tissue. Proteins that were perturbed in expression level in the peripheral or in the central part of the tumor as compared with the non-involved part included S100A11, HNRNPF, HNRNPH1 or HNRNPH2, GSTP1, PKM and FABP1. These identified markers may have future diagnostic potential or may be novel treatment targets after further evaluation in larger patient cohorts.
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Rab MAE, Van Oirschot BA, Kosinski PA, Hixon J, Johnson K, Chubukov V, Dang L, Pasterkamp G, Van Straaten S, Van Solinge WW, Van Beers EJ, Kung C, Van Wijk R. AG-348 (Mitapivat), an allosteric activator of red blood cell pyruvate kinase, increases enzymatic activity, protein stability, and ATP levels over a broad range of PKLR genotypes. Haematologica 2021; 106:238-249. [PMID: 31974203 PMCID: PMC7776327 DOI: 10.3324/haematol.2019.238865] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 01/23/2020] [Indexed: 11/10/2022] Open
Abstract
Pyruvate kinase (PK) deficiency is a rare hereditary disorder affecting red blood cell (RBC) glycolysis, causing changes in metabolism including a deficiency in adenosine triphosphate (ATP). This affects red cell homeostasis, promoting premature removal of RBC from the circulation. In this study, we characterized and evaluated the effect of AG-348, an allosteric activator of PK that is currently in clinical trials for treatment of PK deficiency, on RBC and erythroid precursors from PK-deficient patients. In 15 patients, ex vivo treatment with AG-348 resulted in increased enzymatic activity in all patients' cells after 24 hours (h) (mean increase: 1.8-fold; range: 1.2-3.4). ATP levels increased (mean increase: 1.5-fold; range: 1.0-2.2) similar to control cells (mean increase: 1.6-fold; range: 1.4-1.8). Generally, PK thermostability was strongly reduced in PK-deficient RBC. Ex vivo treatment with AG-348 increased residual activity from 1.4- to >10-fold more than residual activity of vehicle-treated samples. Protein analyses suggest that a sufficient level of PK protein is required for cells to respond to AG- 348 treatment ex vivo, as treatment effects were minimal in patient cells with very low or undetectable levels of PK-R. In half of the patients, ex vivo treatment with AG-348 was associated with an increase in RBC deformability. These data support the hypothesis that drug intervention with AG- 348 effectively up-regulates PK enzymatic activity and increases stability in PK-deficient RBC over a broad range of PKLR genotypes. The concomitant increase in ATP levels suggests that glycolytic pathway activity may be restored. AG-348 treatment may represent an attractive way to correct the underlying pathologies of PK deficiency. (AG-348 is currently in clinical trials for the treatment of PK deficiency. Registered at clinicaltrials.gov identifiers: NCT02476916, NCT03853798, NCT03548220, NCT03559699).
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Affiliation(s)
- Minke A E Rab
- Laboratory of Clinical Chemistry and Haematology, University Medical Center Utrecht
| | - Brigitte A Van Oirschot
- Laboratory of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands
| | | | | | | | | | - Lenny Dang
- Agios Pharmaceuticals, Inc., Cambridge, MA
| | - Gerard Pasterkamp
- Laboratory of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands
| | | | - Wouter W Van Solinge
- Laboratory of Clinical Chemistry and Haematology, University Medical Center Utrecht
| | - Eduard J Van Beers
- Van Creveldkliniek, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | | | - Richard Van Wijk
- Laboratory of Clinical Chemistry and Haematology, University Medical Center Utrecht
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6
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Bianchi P, Fermo E. Molecular heterogeneity of pyruvate kinase deficiency. Haematologica 2020; 105:2218-2228. [PMID: 33054047 PMCID: PMC7556514 DOI: 10.3324/haematol.2019.241141] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 07/03/2020] [Indexed: 01/19/2023] Open
Abstract
Red cell pyruvate kinase (PK) deficiency is the most common glycolytic defect associated with congenital non-spherocytic hemolytic anemia. The disease, transmitted as an autosomal recessive trait, is caused by mutations in the PKLR gene and is characterized by molecular and clinical heterogeneity; anemia ranges from mild or fully compensated hemolysis to life-threatening forms necessitating neonatal exchange transfusions and/or subsequent regular transfusion support; complications include gallstones, pulmonary hypertension, extramedullary hematopoiesis and iron overload. Since identification of the first pathogenic variants responsible for PK deficiency in 1991, more than 300 different variants have been reported, and the study of molecular mechanisms and the existence of genotype-phenotype correlations have been investigated in-depth. In recent years, during which progress in genetic analysis, next-generation sequencing technologies and personalized medicine have opened up important landscapes for diagnosis and study of molecular mechanisms of congenital hemolytic anemias, genotyping has become a prerequisite for accessing new treatments and for evaluating disease state and progression. This review examines the extensive molecular heterogeneity of PK deficiency, focusing on the diagnostic impact of genotypes and new acquisitions on pathogenic non-canonical variants. The recent progress and the weakness in understanding the genotype-phenotype correlation, and its practical usefulness in light of new therapeutic opportunities for PK deficiency are also discussed.
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MESH Headings
- Anemia, Hemolytic, Congenital/diagnosis
- Anemia, Hemolytic, Congenital/genetics
- Anemia, Hemolytic, Congenital/therapy
- Anemia, Hemolytic, Congenital Nonspherocytic/diagnosis
- Anemia, Hemolytic, Congenital Nonspherocytic/genetics
- Humans
- Mutation
- Pyruvate Kinase/deficiency
- Pyruvate Kinase/genetics
- Pyruvate Metabolism, Inborn Errors/diagnosis
- Pyruvate Metabolism, Inborn Errors/genetics
- Pyruvate Metabolism, Inborn Errors/therapy
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Affiliation(s)
- Paola Bianchi
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, UOC Ematologia, UOS Fisiopatologia delle Anemie, Milan, Italy.
| | - Elisa Fermo
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, UOC Ematologia, UOS Fisiopatologia delle Anemie, Milan, Italy
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7
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Bianchi P, Fermo E, Glader B, Kanno H, Agarwal A, Barcellini W, Eber S, Hoyer JD, Kuter DJ, Maia TM, Mañu-Pereira MDM, Kalfa TA, Pissard S, Segovia JC, van Beers E, Gallagher PG, Rees DC, van Wijk R. Addressing the diagnostic gaps in pyruvate kinase deficiency: Consensus recommendations on the diagnosis of pyruvate kinase deficiency. Am J Hematol 2019; 94:149-161. [PMID: 30358897 DOI: 10.1002/ajh.25325] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 10/19/2018] [Accepted: 10/20/2018] [Indexed: 01/19/2023]
Abstract
Pyruvate kinase deficiency (PKD) is the most common enzyme defect of glycolysis and an important cause of hereditary, nonspherocytic hemolytic anemia. The disease has a worldwide geographical distribution but there are no verified data regarding its frequency. Difficulties in the diagnostic workflow and interpretation of PK enzyme assay likely play a role. By the creation of a global PKD International Working Group in 2016, involving 24 experts from 20 Centers of Expertise we studied the current gaps in the diagnosis of PKD in order to establish diagnostic guidelines. By means of a detailed survey and subsequent discussions, multiple aspects of the diagnosis of PKD were evaluated and discussed by members of Expert Centers from Europe, USA, and Asia directly involved in diagnosis. Broad consensus was reached among the Centers on many clinical and technical aspects of the diagnosis of PKD. The results of this study are here presented as recommendations for the diagnosis of PKD and used to prepare a diagnostic algorithm. This information might be helpful for other Centers to deliver timely and appropriate diagnosis and to increase awareness in PKD.
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Affiliation(s)
- Paola Bianchi
- UOC Ematologia, Fisiopatologia delle Anemie; Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico; Milan Italy
| | - Elisa Fermo
- UOC Ematologia, Fisiopatologia delle Anemie; Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico; Milan Italy
| | - Bertil Glader
- Lucile Packard Children's Hospital; Stanford University School of Medicine; Palo Alto California
| | - Hitoshi Kanno
- Department of Transfusion Medicine and Cell Processing; Faculty of Medicine, Tokyo Women's Medical University; Tokyo Japan
| | | | - Wilma Barcellini
- UOC Ematologia, Fisiopatologia delle Anemie; Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico; Milan Italy
| | - Stefan Eber
- Special Praxis for Pediatric Hematology and Childrens’ Hospital; Technical University; Munich Germany
| | - James D. Hoyer
- Department of Laboratory Medicine and Pathology; Mayo Clinic; Rochester Minnesota
| | - David J. Kuter
- Hematology Division; Massachusetts General Hospital; Boston Massachusetts
| | | | | | - Theodosia A. Kalfa
- Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center and Department of Pediatrics; University of Cincinnati, College of Medicine; Cincinnati Ohio
| | - Serge Pissard
- APHP-University Hospital Henri Mondor and Inserm IMRB U955eq2; Creteil France
| | - José-Carlos Segovia
- Differentiation and Cytometry Unit. Hematopoietic Innovative Therapies Division, Centro de Investigaciones Energéticas; Medioambientales y Tecnológicas (CIEMAT) - Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER); Madrid Spain
- Advance Therapies Mixed Unit; Instituto de Investigación Sanitaria-Fundación Jimenez Díaz (IIS-FJD); Madrid Spain
| | - Eduard van Beers
- Van Creveldkliniek, University Medical Center Utrecht; University of Utrecht; Utrecht The Netherlands
| | - Patrick G. Gallagher
- Departments of Pediatrics, Pathology and Genetics; Yale University School of Medicine; New Haven Connecticut
| | - David C. Rees
- Department of Paediatric Haematology; King's College Hospital; London United Kingdom
| | - Richard van Wijk
- Department of Clinical Chemistry and Haematology, Division Laboratories, Pharmacy and Biomedical Genetics; University Medical Center Utrecht, Utrecht University; Utrecht The Netherlands
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8
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He Y, Luo J, Lei Y, Jia S, Liao N. A novel PKLR gene mutation identified using advanced molecular techniques. Pediatr Transplant 2018; 22. [PMID: 29349879 DOI: 10.1111/petr.13143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/29/2017] [Indexed: 01/19/2023]
Abstract
This study's purposes were to diagnose intractable hemolytic anemia and to provide guiding treatment for the affected family members. We performed NGS in a panel of 600 genes for blood diseases on a patient with obscure hemolytic anemia and her parents. We confirmed the diagnosis of pyruvate kinase deficiency, identified a novel homozygous mutation of the PKLR gene (NM_000298: exon 6: c.T941C: p.I314T), and ruled out other blood diseases in the Chinese family. Furthermore, amniotic fluid was taken from the mother during the second trimester, and DNA was extracted to analyze the type of PKLR gene mutation. The proband received cord blood and bone marrow from the second child of the mother for hematopoietic stem cell transplantation and achieved normal hematopoiesis. The genetic characterization analysis and genotype-phenotype correlation study of PKLR gene suggested that NGS was an effective method to confirm the molecular diagnosis of intractable hemolytic anemia. The identification of the mutation aided in prenatal diagnosis in the second pregnancy and the effective clinical management of the affected family.
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Affiliation(s)
- Yunyan He
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Guangxi Key Laboratory of Thalassemia Research, Nanning, Guangxi Province, China
| | - Jianming Luo
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Guangxi Key Laboratory of Thalassemia Research, Nanning, Guangxi Province, China
| | - Yonghong Lei
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Guangxi Key Laboratory of Thalassemia Research, Nanning, Guangxi Province, China
| | - Siyuan Jia
- Guangxi Medical University, Nanning, Guangxi Province, China
| | - Ning Liao
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Guangxi Key Laboratory of Thalassemia Research, Nanning, Guangxi Province, China
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9
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Faik I, van Tong H, Lell B, Meyer CG, Kremsner PG, Velavan TP. Pyruvate Kinase and Fcγ Receptor Gene Copy Numbers Associated With Malaria Phenotypes. J Infect Dis 2017; 216:276-282. [PMID: 28605553 DOI: 10.1093/infdis/jix284] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 06/08/2017] [Indexed: 12/26/2022] Open
Abstract
Genetic factors are associated with susceptibility to many infectious diseases and may be determinants of clinical progression. Gene copy number variation (CNV) has been shown to be associated with phenotypes of numerous diseases, including malaria. We quantified gene copy numbers of the pyruvate kinase, liver, and red blood cell (PKLR) gene as well as of the Fcγ receptor 2A and Fcγ receptor 2C (FCGR2A, FCGR2C) and Fcγ receptor 3 (FCGR3) genes using real-time quantitative polymerase chain reaction (RT-qPCR) assays in Gabonese children with severe (n = 184) or and mild (n = 189) malaria and in healthy Gabonese and white individuals (n = 76 each). The means of PKLR, FCGR2A, FCGR2C, and FCGR3 copy numbers were significantly higher among children with severe malaria compared to those with mild malaria (P < .002), indicating that a surplus of copies of those genes is significantly associated with malaria severity. Copy numbers of the FCGR2A and FCGR2C genes were significantly lower (P = .005) in Gabonese individuals compared with white individuals. In conclusion, CNV of the PKLR, FCGR2A, FCGR2C, and FCGR3 genes is associated with malaria severity, and our results provide evidence for a role of CNV in host responses to malaria.
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Affiliation(s)
- Imad Faik
- Institute of Tropical Medicine, University of Tübingen, Germany
| | - Hoang van Tong
- Institute of Tropical Medicine, University of Tübingen, Germany.,Vietnamese-German Center for Medical Research, Hanoi, Vietnam
| | - Bertrand Lell
- Institute of Tropical Medicine, University of Tübingen, Germany.,Centre de Recherche Médicale de Lambaréné, Gabon
| | - Christian G Meyer
- Institute of Tropical Medicine, University of Tübingen, Germany.,Vietnamese-German Center for Medical Research, Hanoi, Vietnam.,Faculty of Medicine, Duy Tan University, Da Nang, Vietnam
| | - Peter G Kremsner
- Institute of Tropical Medicine, University of Tübingen, Germany.,Centre de Recherche Médicale de Lambaréné, Gabon
| | - Thirumalaisamy P Velavan
- Institute of Tropical Medicine, University of Tübingen, Germany.,Vietnamese-German Center for Medical Research, Hanoi, Vietnam.,Fondation Congolaise pour la Recherche Médicale, Brazzaville, Republic of Congo.,Faculty of Medicine, Duy Tan University, Da Nang, Vietnam
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10
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Larochelle A, Magny P, Tremblay S, De Médicis É. Pyruvate Kinase Deficiency which Causes Nonspherocytic Hemolytic Anemia: The Gene and its Mutations. Hematology 2016; 4:77-87. [DOI: 10.1080/10245332.1999.11746433] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- André Larochelle
- Faculty of Medicine, University of Sherbrooke, Quebec, Canada, J1H 5N4
| | - Pierre Magny
- Faculty of Medicine, University of Sherbrooke, Quebec, Canada, J1H 5N4
| | - Sophie Tremblay
- Faculty of Medicine, University of Sherbrooke, Quebec, Canada, J1H 5N4
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11
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Phenotypic and molecular genetic analysis of Pyruvate Kinase deficiency in a Tunisian family. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2016. [DOI: 10.1016/j.ejmhg.2015.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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12
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Safe and Efficient Gene Therapy for Pyruvate Kinase Deficiency. Mol Ther 2016; 24:1187-98. [PMID: 27138040 DOI: 10.1038/mt.2016.87] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 03/25/2016] [Indexed: 12/17/2022] Open
Abstract
Pyruvate kinase deficiency (PKD) is a monogenic metabolic disease caused by mutations in the PKLR gene that leads to hemolytic anemia of variable symptomatology and that can be fatal during the neonatal period. PKD recessive inheritance trait and its curative treatment by allogeneic bone marrow transplantation provide an ideal scenario for developing gene therapy approaches. Here, we provide a preclinical gene therapy for PKD based on a lentiviral vector harboring the hPGK eukaryotic promoter that drives the expression of the PKLR cDNA. This therapeutic vector was used to transduce mouse PKD hematopoietic stem cells (HSCs) that were subsequently transplanted into myeloablated PKD mice. Ectopic RPK expression normalized the erythroid compartment correcting the hematological phenotype and reverting organ pathology. Metabolomic studies demonstrated functional correction of the glycolytic pathway in RBCs derived from genetically corrected PKD HSCs, with no metabolic disturbances in leukocytes. The analysis of the lentiviral insertion sites in the genome of transplanted hematopoietic cells demonstrated no evidence of genotoxicity in any of the transplanted animals. Overall, our results underscore the therapeutic potential of the hPGK-coRPK lentiviral vector and provide high expectations toward the gene therapy of PKD and other erythroid metabolic genetic disorders.
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13
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Canu G, De Bonis M, Minucci A, Capoluongo E. Red blood cell PK deficiency: An update of PK-LR gene mutation database. Blood Cells Mol Dis 2016; 57:100-9. [PMID: 26832193 DOI: 10.1016/j.bcmd.2015.12.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 12/21/2015] [Accepted: 12/29/2015] [Indexed: 11/16/2022]
Abstract
Pyruvate kinase (PK) deficiency is known as being the most common cause of chronic nonspherocytic hemolytic anemia (CNSHA). Clinical PK deficiency is transmitted as an autosomal recessive trait, that can segregate neither in homozygous or in a compound heterozygous modality, respectively. Two PK genes are present in mammals: the pyruvate kinase liver and red blood cells (PK-LR) and the pyruvate kinase muscle (PK-M), of which only the first encodes for the isoenzymes normally expressed in the red blood cells (R-type) and in the liver (L-type). Several reports have been published describing a large variety of genetic defects in PK-LR gene associated to CNSHA. Herein, we present a review of about 250 published mutations and six polymorphisms in PK-LR gene with the corresponding clinical and molecular data. We consulted the PubMed website for searching mutations and papers, along with two main databases: the Leiden Open Variation Database (LOVD, https://grenada.lumc.nl/LOVD2/mendelian_genes/home.php?select_db=PKLR) and Human Gene Mutation Database (HGMD, http://www.hgmd.cf.ac.uk/ac/gene.php?gene=PKLR) for selecting, reviewing and listing the annotated PK-LR gene mutations present in literature. This paper is aimed to provide useful information to clinicians and laboratory professionals regarding overall reported PK-LR gene mutations, also giving the opportunity to harmonize data regarding PK-deficient individuals.
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Affiliation(s)
- Giulia Canu
- Laboratory of Clinical Molecular and Personalized Diagnostics, Department of Laboratory Medicine, "A Gemelli" Hospital, Catholic University, Largo Agostino Gemelli 8, Roma, Italy.
| | - Maria De Bonis
- Laboratory of Clinical Molecular and Personalized Diagnostics, Department of Laboratory Medicine, "A Gemelli" Hospital, Catholic University, Largo Agostino Gemelli 8, Roma, Italy
| | - Angelo Minucci
- Laboratory of Clinical Molecular and Personalized Diagnostics, Department of Laboratory Medicine, "A Gemelli" Hospital, Catholic University, Largo Agostino Gemelli 8, Roma, Italy.
| | - Ettore Capoluongo
- Laboratory of Clinical Molecular and Personalized Diagnostics, Department of Laboratory Medicine, "A Gemelli" Hospital, Catholic University, Largo Agostino Gemelli 8, Roma, Italy
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14
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van Bruggen R, Gualtieri C, Iliescu A, Louicharoen Cheepsunthorn C, Mungkalasut P, Trape JF, Modiano D, Sodiomon Sirima B, Singhasivanon P, Lathrop M, Sakuntabhai A, Bureau JF, Gros P. Modulation of Malaria Phenotypes by Pyruvate Kinase (PKLR) Variants in a Thai Population. PLoS One 2015; 10:e0144555. [PMID: 26658699 PMCID: PMC4677815 DOI: 10.1371/journal.pone.0144555] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 11/19/2015] [Indexed: 01/11/2023] Open
Abstract
Pyruvate kinase (PKLR) is a critical erythrocyte enzyme that is required for glycolysis and production of ATP. We have shown that Pklr deficiency in mice reduces the severity (reduced parasitemia, increased survival) of blood stage malaria induced by infection with Plasmodium chabaudi AS. Likewise, studies in human erythrocytes infected ex vivo with P. falciparum show that presence of host PK-deficiency alleles reduces infection phenotypes. We have characterized the genetic diversity of the PKLR gene, including haplotype structure and presence of rare coding variants in two populations from malaria endemic areas of Thailand and Senegal. We investigated the effect of PKLR genotypes on rich longitudinal datasets including haematological and malaria-associated phenotypes. A coding and possibly damaging variant (R41Q) was identified in the Thai population with a minor allele frequency of ~4.7%. Arginine 41 (R41) is highly conserved in the pyruvate kinase family and its substitution to Glutamine (R41Q) affects protein stability. Heterozygosity for R41Q is shown to be associated with a significant reduction in the number of attacks with Plasmodium falciparum, while correlating with an increased number of Plasmodium vivax infections. These results strongly suggest that PKLR protein variants may affect the frequency, and the intensity of malaria episodes induced by different Plasmodium parasites in humans living in areas of endemic malaria.
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MESH Headings
- Amino Acid Sequence
- Amino Acid Substitution
- Animals
- Base Sequence
- Disease Susceptibility
- Erythrocytes/enzymology
- Erythrocytes/parasitology
- Gene Expression
- Genotype
- Humans
- Malaria/enzymology
- Malaria/genetics
- Malaria/pathology
- Malaria, Falciparum/enzymology
- Malaria, Falciparum/epidemiology
- Malaria, Falciparum/genetics
- Malaria, Falciparum/pathology
- Malaria, Vivax/enzymology
- Malaria, Vivax/epidemiology
- Malaria, Vivax/genetics
- Malaria, Vivax/pathology
- Mice
- Mice, Knockout
- Parasitemia/enzymology
- Parasitemia/epidemiology
- Parasitemia/genetics
- Parasitemia/pathology
- Phenotype
- Plasmodium chabaudi/physiology
- Plasmodium falciparum/physiology
- Plasmodium vivax/physiology
- Polymorphism, Single Nucleotide
- Protein Stability
- Pyruvate Kinase/chemistry
- Pyruvate Kinase/genetics
- Pyruvate Kinase/metabolism
- Senegal/epidemiology
- Sequence Alignment
- Severity of Illness Index
- Thailand/epidemiology
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Affiliation(s)
- Rebekah van Bruggen
- Department of Human Genetics, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Christian Gualtieri
- Department of Biochemistry, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Alexandra Iliescu
- Department of Biochemistry, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | | | - Punchalee Mungkalasut
- Department of Biochemistry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand, 10330
| | - Jean-François Trape
- Laboratoire de Paludologie et Zoologie Médicale, Institut de Recherche pour le Développement, Dakar, Sénégal
| | - David Modiano
- Department of Public Health and Infectious Diseases, Instituto Pasteur-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy
| | - Bienvenu Sodiomon Sirima
- Centre National de Recherche et de Formation sur le Paludisme, Ministry of Health, Ouagadougou, Burkina Faso
| | - Pratap Singhasivanon
- Department of Tropical Hygiene (Biomedical and Health Informatics), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Mark Lathrop
- Department of Human Genetics, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Anavaj Sakuntabhai
- Unité de la Génétique Fonctionnelle des Maladies Infectieuses, Institut Pasteur, Paris, France
- Centre National de la Recherche Scientifique, URA3012, F-75015, Paris, France
| | - Jean-François Bureau
- Unité de la Génétique Fonctionnelle des Maladies Infectieuses, Institut Pasteur, Paris, France
- Centre National de la Recherche Scientifique, URA3012, F-75015, Paris, France
| | - Philippe Gros
- Department of Human Genetics, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
- Department of Biochemistry, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
- * E-mail:
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15
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Chaman N, Iqbal MA, Siddiqui FA, Gopinath P, Bamezai RNK. ERK2-Pyruvate Kinase Axis Permits Phorbol 12-Myristate 13-Acetate-induced Megakaryocyte Differentiation in K562 Cells. J Biol Chem 2015; 290:23803-15. [PMID: 26269597 DOI: 10.1074/jbc.m115.657411] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Indexed: 11/06/2022] Open
Abstract
Metabolic changes that contribute to differentiation are not well understood. Overwhelming evidence shows the critical role of glycolytic enzyme pyruvate kinase (PK) in directing metabolism of proliferating cells. However, its role in metabolism of differentiating cells is unclear. Here we studied the role of PK in phorbol 12-myristate 13-acetate (PMA)-induced megakaryocytic differentiation in human leukemia K562 cells. We observed that PMA treatment decreased cancer-type anabolic metabolism but increased ATP production, along with up-regulated expression of two PK isoforms (PKM2 and PKR) in an ERK2-dependent manner. Interestingly, silencing of PK (PKM2 and PKR) inhibited PMA-induced megakaryocytic differentiation, as revealed by decreased expression of megakaryocytic differentiation marker CD61 and cell cycle behavior. Further, PMA-induced ATP production reduced greatly upon PK silencing, suggesting that PK is required for ATP synthesis. In addition to metabolic effects, PMA treatment also translocated PKM2, but not PKR, into nucleus. ERK1/2 knockdowns independently and together suggested the role of ERK2 in the up-regulation of both the isoforms of PK, proposing a role of ERK2-PK isoform axis in differentiation. Collectively, our findings unravel ERK2 guided PK-dependent metabolic changes during PMA induction, which are important in megakaryocytic differentiation.
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Affiliation(s)
- Noor Chaman
- From the National Centre of Applied Human Genetics, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Mohammad Askandar Iqbal
- From the National Centre of Applied Human Genetics, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Farid Ahmad Siddiqui
- From the National Centre of Applied Human Genetics, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Prakasam Gopinath
- From the National Centre of Applied Human Genetics, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Rameshwar N K Bamezai
- From the National Centre of Applied Human Genetics, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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16
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Koralkova P, van Solinge WW, van Wijk R. Rare hereditary red blood cell enzymopathies associated with hemolytic anemia - pathophysiology, clinical aspects, and laboratory diagnosis. Int J Lab Hematol 2014; 36:388-97. [DOI: 10.1111/ijlh.12223] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 02/28/2014] [Indexed: 02/06/2023]
Affiliation(s)
- P. Koralkova
- Department of Biology; Faculty of Medicine and Dentistry; Palacky University; Olomouc Czech Republic
| | - W. W. van Solinge
- Department of Clinical Chemistry and Haematology; University Medical Center Utrecht; Utrecht the Netherlands
| | - R. van Wijk
- Department of Clinical Chemistry and Haematology; University Medical Center Utrecht; Utrecht the Netherlands
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17
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Warang P, Kedar P, Ghosh K, Colah R. Molecular and clinical heterogeneity in pyruvate kinase deficiency in India. Blood Cells Mol Dis 2013; 51:133-7. [PMID: 23770304 DOI: 10.1016/j.bcmd.2013.05.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 05/12/2013] [Accepted: 05/13/2013] [Indexed: 01/30/2023]
Abstract
We studied the PK-LR gene in 10 unrelated Indian patients with congenital haemolytic anemia associated with erythrocyte pyruvate kinase deficiency. The patients had a variable presentation ranging from a very mild compensated hemolysis to severe anemia. Nine different mutations were detected among the 20 mutated alleles identified: one deletion (c.1042-1044del) p.Lys348del and eight single-nucleotide (nt) substitutions resulting in amino acid exchanges c.397A>G (p.Asn133Asp), c.992A>G (p.Asp331Gly), c.1072G>A (p.Gly358Arg), c.1076G>A (p.Arg359His), c.1219G>A (p.Glu407Lys), c.1241C>T (p.Pro414Leu), c.1436G>A (p.Arg479His) and c.1529G>A (p.Arg510Gln) were identified. Although all the exons, the flanking regions and the promoter region were sequenced in all cases, we failed to detect the second expected mutation in two subjects. Two mutations [c.397A>G; c.1241C>T] were novel. These novel missense mutations involved highly conserved amino acids. Two mutations were identified for the first time in the homozygous state globally (c1042-1044del; c.1072G>A) and two other mutations were identified for the first time in our population (c.1076G>A; c.1529G>A). This study along with our earlier report suggests that the most frequent mutations in India would appear to be c.1436G>A (18.33%), followed by c.992A>G (11.66%) and c.1456C>T (11.66%). Structural implications of amino acid substitutions were correlated with the clinical phenotypes seen.
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Affiliation(s)
- Prashant Warang
- National Institute of Immunohaematology (Indian Council of Medical Research), K.E.M. Hospital Campus, Parel, Mumbai, India
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18
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van Wijk R, Huizinga EG, van Wesel AC, van Oirschot BA, A. Hadders M, van Solinge WW. Fifteen novel mutations inPKLRassociated with pyruvate kinase (PK) deficiency: Structural implications of amino acid substitutions in PK. Hum Mutat 2009; 30:446-53. [DOI: 10.1002/humu.20915] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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19
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Affiliation(s)
- Fuad El Rassi
- Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon
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20
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Zanella A, Fermo E, Bianchi P, Chiarelli LR, Valentini G. Pyruvate kinase deficiency: the genotype-phenotype association. Blood Rev 2007; 21:217-31. [PMID: 17360088 DOI: 10.1016/j.blre.2007.01.001] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Red cell pyruvate kinase (PK) deficiency is the most frequent enzyme abnormality of glycolysis causing chronic non-spherocytic haemolytic anaemia. The disease is transmitted as an autosomal recessive trait, clinical symptoms usually occurring in compound heterozygotes for two mutant alleles and in homozygotes. The severity of haemolysis is highly variable, ranging from very mild or fully compensated forms to life-threatening neonatal anaemia necessitating exchange transfusions. Erythrocyte PK is synthesised under the control of the PK-LR gene located on chromosome 1. One hundred eighty different mutations in PK-LR gene, mostly missense, have been so far reported associated to PK deficiency. First attempts to delineate the genotype-phenotype association were mainly based on the analysis of the enzyme's three-dimensional structure and the observation of the few homozygous patients. More recently, the comparison of the recombinant mutants of human red cell PK with the wild-type enzyme has enabled the effects of amino acid replacements on the enzyme molecular properties to be determined. However, the clinical manifestations of red cell enzyme defects are not merely dependent on the molecular properties of the mutant protein but rather reflect the complex interactions of additional factors, including genetic background, concomitant functional polymorphisms of other enzymes, posttranslational or epigenetic modifications, ineffective erythropoiesis and differences in splenic function.
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Affiliation(s)
- Alberto Zanella
- Department of Haematology, Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Milan, Italy.
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21
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Zanella A, Fermo E, Bianchi P, Valentini G. Red cell pyruvate kinase deficiency: molecular and clinical aspects. Br J Haematol 2005; 130:11-25. [PMID: 15982340 DOI: 10.1111/j.1365-2141.2005.05527.x] [Citation(s) in RCA: 136] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Red cell pyruvate kinase (PK) deficiency is the most frequent enzyme abnormality of the glycolytic pathway causing hereditary non-spherocytic haemolytic anaemia. The degree of haemolysis varies widely, ranging from very mild or fully compensated forms, to life-threatening neonatal anaemia and jaundice necessitating exchange transfusions. Erythrocyte PK is synthesized under the control of the PK-LR gene located on chromosome 1. To date, more than 150 different mutations in the PK-LR gene have been associated with PK deficiency. First attempts to delineate the biochemical and clinical consequences of the molecular defect were mainly based on the observation of the few homozygous patients and on the analysis of the three-dimensional structure of the enzyme. More recently, the comparison of the recombinant mutants of human red cell PK with the wild-type enzyme has enabled the effects of amino acid replacements on the enzyme molecular properties to be determined and help to correlate genotype to clinical phenotype.
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Affiliation(s)
- Alberto Zanella
- Department of Haematology, IRCCS Ospedale Maggiore, Milan, Italy.
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22
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van Wijk R, van Solinge WW. The energy-less red blood cell is lost: erythrocyte enzyme abnormalities of glycolysis. Blood 2005; 106:4034-42. [PMID: 16051738 DOI: 10.1182/blood-2005-04-1622] [Citation(s) in RCA: 205] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The red blood cell depends solely on the anaerobic conversion of glucose by the Embden-Meyerhof pathway for the generation and storage of high-energy phosphates, which is necessary for the maintenance of a number of vital functions. Many red blood cell enzymopathies have been described that disturb the erythrocyte's integrity, shorten its cellular survival, and result in hemolytic anemia. By far the majority of these enzymopathies are hereditary in nature. In this review, we summarize the current knowledge regarding the genetic, biochemical, and structural features of clinically relevant red blood cell enzymopathies involved in the Embden-Meyerhof pathway and the Rapoport-Luebering shunt.
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Affiliation(s)
- Richard van Wijk
- Department of Laboratory Medicine, Rm G03.550, University Medical Center Utrecht, PO Box 85500, 3508 GA, Utrecht, The Netherlands
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23
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van Wijk R, van Solinge WW, Nerlov C, Beutler E, Gelbart T, Rijksen G, Nielsen FC. Disruption of a novel regulatory element in the erythroid-specific promoter of the human PKLR gene causes severe pyruvate kinase deficiency. Blood 2003; 101:1596-602. [PMID: 12393511 DOI: 10.1182/blood-2002-07-2321] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We established the molecular basis for pyruvate kinase (PK) deficiency in a white male patient with severe nonspherocytic hemolytic anemia. The paternal allele exhibited the common PKLR cDNA sequence (c.) 1529G>A mutation, known to be associated with PK deficiency. On the maternal allele, 3 in cis mutations were identified in the erythroid-specific promoter region of the gene: one deletion of thymine -248 and 2 single nucleotide substitutions, nucleotide (nt) -324T>A and nt -83G>C. Analysis of the patient's RNA demonstrated the presence of only the 1529A allele, indicating severely reduced transcription from the allele linked to the mutated promoter region. Transfection of promoter constructs into erythroleukemic K562 cells showed that the most upstream -324T>A and -248delT mutations were nonfunctional polymorphisms. In contrast, the -83G>C mutation strongly reduced promoter activity. Site-directed mutagenesis of the promoter region revealed the presence of a putative regulatory element (PKR-RE1) whose core binding motif, CTCTG, is located between nt -87 and nt -83. Electrophoretic mobility shift assay using K562 nuclear extracts indicated binding of an as-yet-unidentified trans-acting factor. This novel element mediates the effects of factors necessary for regulation of pyruvate kinase gene expression during red cell differentiation and maturation.
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Affiliation(s)
- Richard van Wijk
- Department of Clinical Chemistry, University Medical Center Utrecht, The Netherlands
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24
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Manco L, Ribeiro ML, Máximo V, Almeida H, Costa A, Freitas O, Barbot J, Abade A, Tamagnini G. A new PKLR gene mutation in the R-type promoter region affects the gene transcription causing pyruvate kinase deficiency. Br J Haematol 2000; 110:993-7. [PMID: 11054094 DOI: 10.1046/j.1365-2141.2000.02283.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mutations in the PKLR gene responsible for pyruvate kinase (PK)-deficient anaemia are mainly located in the coding regions: 11 are in the splicing sites and, recently, three mutations have been described in the promoter region. We now report a novel point mutation A-->G on nucleotide 72, upstream from the initiation codon of the PKLR gene, in four Portuguese PK-deficient patients. This new regulatory mutation occurs within the most proximal of the four GATA motifs (GATA-A element) in the R-type promoter region. In two patients who were homozygous for this mutation, a semiquantitative reverse transcription polymerase chain reaction (PCR) procedure was used to evaluate the amount of R-PK mRNA transcript in the reticulocytes. The mRNA level was about five times lower than in normal controls, demonstrating that the PKLR gene transcription is severely affected, most probably because the -72A-->G point mutation disables the binding of the erythroid transcription factor GATA-1 to the GATA-A element. Supporting these data, the two patients homozygous for the -72A-->G mutation had severe haemolytic anaemia and were transfusion dependent until splenectomy. Two other patients who were compound heterozygous for this mutation and the previously described missense mutation 1456C-->T had a mild condition.
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Affiliation(s)
- L Manco
- Unidade de Hematologia Molecular, Centro Hospitalar de Coimbra, Portugal.
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25
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Zanella A, Bianchi P. Red cell pyruvate kinase deficiency: from genetics to clinical manifestations. Best Pract Res Clin Haematol 2000; 13:57-81. [PMID: 10916678 DOI: 10.1053/beha.1999.0057] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Pyruvate kinase deficiency is the most frequent enzyme abnormality of the Embden-Meyerhof pathway causing hereditary non-spherocytic haemolytic anaemia. The degree of haemolysis varies widely, ranging from very mild or fully compensated forms, to life-threatening neonatal anaemia and jaundice necessitating exchange transfusions. Splenectomy should be reserved for young patients who require regular blood transfusions. The gene encoding for pyruvate kinase (PK-LR) has been localized to the long arm of chromosome I; the cDNA of R-type is 2060 bp long and codes for 574 amino acids. More than 130 different mutations, mostly missense, have so far been described in association with PK deficiency, 1529A and 1456T being considered to be the most common mutations in Caucasians. Analysis of the three-dimensional structure of the enzyme may help in predicting the severity of the molecular defect. Further data on clinical features of homozygous patients are needed, at least for some mutations, to allow a more precise genotype/phenotype correlation.
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MESH Headings
- Anemia, Hemolytic, Congenital Nonspherocytic/diagnosis
- Anemia, Hemolytic, Congenital Nonspherocytic/enzymology
- Anemia, Hemolytic, Congenital Nonspherocytic/genetics
- Anemia, Hemolytic, Congenital Nonspherocytic/therapy
- Chromosomes, Human, Pair 1
- DNA/chemistry
- Erythrocytes/enzymology
- Humans
- Molecular Structure
- Mutation
- Pyruvate Kinase/chemistry
- Pyruvate Kinase/deficiency
- Pyruvate Kinase/genetics
- Pyruvate Kinase/physiology
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Affiliation(s)
- A Zanella
- Division of Haematology, IRCCS Ospedale Maggiore, Milan, Italy
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26
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Murakami K, Kanno H, Miwa S, Piomelli S. Human HKR isozyme: organization of the hexokinase I gene, the erythroid-specific promoter, and transcription initiation site. Mol Genet Metab 1999; 67:118-30. [PMID: 10356311 DOI: 10.1006/mgme.1999.2842] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We previously described a cDNA for the human HKR isozyme, whose sequence is identical to that of the ubiquitous HKI isozyme, except for a unique 5' end sequence. Screening a human genomic library with a DNA fragment containing an erythroid-specific sequence we found one clone including 5' ends for both HKR and HKI genes. The first HKR exon was located 3 kb 5' of the first HKI exon. These results confirmed that HKR is produced from the HKI gene by alternate promoter and splicing. The HKI gene consisted of 19 exons. All exon-intron boundaries are conserved among the genes for hexokinase and glucokinase. The HKI gene length was estimated at over 67 kb. The initiation site for the HKR was identified by primer extension. Its promoter did not have a canonical TATA box, but an inverted GATA at nt -177 (i.e., 36 nt 5' to the transcription initiation site). In the HKR promoter a DNA fragment spanning nt -275 to nt -107 exhibited erythroid-specific activity. However, this was absent in shorter promoter fragments (nt -206 to -107 or nt -229 to -107). The sequence nt -275 to -229, which appeared critical for the erythroid-specific expression of the HKR gene, contained a consensus motif for Sp-1 and GATA, CCAAT, and GGAA motifs. The electrophoretic mobility shift assay (EMSA) suggested erythroid-specific cooperative protein-protein interaction in this region. Deletion of the GATA sequence as well as reaction with a specific antibody identified GATA-1 as one of the interacting proteins.
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Affiliation(s)
- K Murakami
- Division of Pediatric Hematology, Columbia University College of Physicians and Surgeons, New York 10032, USA
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27
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Kugler W, Laspe P, Stahl M, Schröter W, Lakomek M. Identification of a novel promoter mutation in the human pyruvate kinase (PK) LR gene of a patient with severe haemolytic anaemia. Br J Haematol 1999; 105:596-8. [PMID: 10354118 DOI: 10.1046/j.1365-2141.1999.01386.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Using direct sequencing we analysed the pyruvate kinase (PK) LR gene of a patient with severe haemolytic anaemia due to PK deficiency. A novel promoter mutation -249delA relative to the translation initiation site and the common 1529A mutation in exon 11 of the gene could be identified. Reverse transcription (RT)-PCR analysis combined with restriction digestion revealed that the -249delA mutation leads to a reduction in the amount of mRNA produced from this allele to about 6% of normal. We assume that both mutations would account for the PK deficiency in the compound heterozygous patient.
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Affiliation(s)
- W Kugler
- Universitäts-Kinderklinik, Göttingen, Germany
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28
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Yamada K, Tanaka T, Noguchi T. Characterization and purification of carbohydrate response element-binding protein of the rat L-type pyruvate kinase gene promoter. Biochem Biophys Res Commun 1999; 257:44-9. [PMID: 10092507 DOI: 10.1006/bbrc.1999.0410] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The L-III transcriptional regulatory element of the rat pyruvate kinase L gene is located between -170 and -150 base pairs upstream of the hepatocyte-specific transcription initiation site. As the L-III element is not only necessary for cell type-specific expression but also for transcriptional stimulation by carbohydrates, it is also referred to as a carbohydrate-response element. Electrophoretic mobility shift assays using rat liver nuclear extract showed that L-III element-binding protein (L-IIIBP) was observed as multiple bands. These bands disappeared when the nuclear extract was preincubated at 60 degrees C for 5 min and were competed with unlabeled L-III oligonucleotide but not with unlabeled adenovirus major late promoter E box oligonucleotide. In addition, these bands were not affected in the presence of antiserum against upstream stimulating factor (USF). Thus, we conclude that L-IIIBP is different from USF. Then, heat-labile L-IIIBP was purified from rat liver nuclear extracts. Purified L-IIIBP exhibited two bands on sodium dodecyl sulfate/polyacrylamide gel electrophoresis by silver staining. Ultraviolet crosslinking experiment showed that both bands had binding activity to the L-III oligonucleotide.
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Affiliation(s)
- K Yamada
- Department of Biochemistry, Fukui Medical University, Shimoaizuki, Matsuoka, Fukui, 910-1193, Japan
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Abstract
Red blood cell enzyme activities are measured mainly to diagnose hereditary nonspherocytic hemolytic anemia associated with enzyme anomalies. At least 15 enzyme anomalies associated with hereditary hemolytic anemia have been reported. Some nonhematologic disease can also be diagnosed by the measurement of red blood cell enzyme activities in the case in which enzymes of red blood cells and the other organs are under the same genetic control. Progress in molecular biology has provided a new perspective. Techniques such as the polymerase chain reaction and single-strand conformation polymorphism analysis have greatly facilitated the molecular analysis of erythroenzymopathies. These studies have clarified the correlation between the functional and structural abnormalities of the variant enzymes. In general, the mutations that induce an alteration of substrate binding site and/or enzyme instability might result in markedly altered enzyme properties and severe clinical symptoms.
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Affiliation(s)
- H Fujii
- Department of Blood Transfusion Medicine, Tokyo Women's Medical College, Japan
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Affiliation(s)
- K Yamada
- Department of Biochemistry, Fukui Medical University, Shimoaizuki, Matsuoka, Fukui, 910-1193, Japan
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Aisaki K, Kanno H, Oyaizu N, Hara Y, Miwa S, Ikawa Y. Apoptotic changes precede mitochondrial dysfunction in red cell-type pyruvate kinase mutant mouse erythroleukemia cell lines. Jpn J Cancer Res 1999; 90:171-9. [PMID: 10189887 PMCID: PMC5926040 DOI: 10.1111/j.1349-7006.1999.tb00730.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Two erythroleukemia cell lines have been established from the splenic lesions of red blood cell-type pyruvate kinase (R-PK) activity-deficient mice of CBA/N origin infected with a polycythemic strain of Friend leukemia virus complex (FVp). Ten to 30% of the cells of these cell lines undergo apoptotic changes in routine passage, as shown by nuclear fragmentation, DNA laddering, DNA content (propidium iodide (PI) staining), and annexin V binding assay. In these cells, however, although adenosine 5'-triphosphate (ATP) levels were lower than in the control cells, the mitochondrial inner transmembrane potential (delta psi m), detected by rhodamine 123 (R123) and diSC3(5) staining, remained unchanged until the final stage of apoptosis. No evidence was obtained to relate this finding to R-PK mutation due to difficulty in cloning stable, conditionally inducible R-PK gene transfectants. However, low delta psi m in the apoptotic cell population of the control T3-K-1 (K-1) and T3-CI-2-0 (2-0) Friend erythroleukemia cells supports a possible relationship, as do results obtained in two Friend erythroleukemia cells recently isolated from normal CBA/N mice. These cell lines are expected to be useful for clarifying both the primary apoptotic changes independent of mitochondrial dysfunction and the PK-isozyme changes during erythrodifferentiation, for example, the decreased muscle type 2 (M2) PK level. Modification of growth signals in these cell lines may modulate differentiation and/or apoptosis and allow further elucidation of the signaling networks.
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Affiliation(s)
- K Aisaki
- Department of Retroviral Regulation, Tokyo Medical and Dental University
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Ruzzo A, Andreoni F, Magnani M. Structure of the human hexokinase type I gene and nucleotide sequence of the 5' flanking region. Biochem J 1998; 331 ( Pt 2):607-13. [PMID: 9531504 PMCID: PMC1219395 DOI: 10.1042/bj3310607] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This study reports the precise intron/exon boundaries and intron/exon composition of the human hexokinase type I gene. A yeast artificial chromosome containing the hexokinase type I gene was isolated from the yeast artificial chromosome library of the Centre d'Etude du Polymorphisme Humaine. A cosmid sublibrary was created and direct sequencing of the individual cosmids was used to provide the exon/intron organization. The human hexokinase type I gene was found to be composed of 18 exons ranging in size from 63 to 305 bp. Intron 1 is at least 15 kb in length, whereas intron 2 spans at least 10 kb. Overall, the length of the 17 introns ranges from 104 to greater than 15 kb. The entire coding region is contained in at least 75 kb of the gene. The structure of the gene reveals a remarkable conservation of the size of the exons compared with glucokinase and hexokinase type II. Isolation of the 5' flanking region of the gene revealed a 75-90% identity with the rat sequence. Direct evidence of an alternative red-blood-cell-specific exon 1 located upstream of the 5' flanking region of the gene is also provided.
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Affiliation(s)
- A Ruzzo
- 'G.Fornaini' Institute of Biological Chemistry, University of Urbino, Via Saffi 2, 61029 Urbino, Italy
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33
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Lenzner C, Nürnberg P, Jacobasch G, Thiele BJ. Complete genomic sequence of the human PK-L/R-gene includes four intragenic polymorphisms defining different haplotype backgrounds of normal and mutant PK-genes. DNA SEQUENCE : THE JOURNAL OF DNA SEQUENCING AND MAPPING 1998; 8:45-53. [PMID: 9522120 DOI: 10.3109/10425179709020884] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The human pyruvate kinase L/R-gene has been completely sequenced in unrelated normal individuals and in pyruvate kinase-deficient patients by a PCR-based direct genomic sequencing approach and analyzed for polymorphisms. The total length of the gene is 8409 nucleotides. Four polymorphic sites have been detected: C/A1705 and C/T1992 in exon 12, a T-stretch in intron 1 occurring in the two polymorphic forms (T)10 and (T)19 and an (ATT)n microsatellite in intron J which has been found in the variation (ATT)11-17. Haplotype analysis using these four markers has been applied to trace the genetic background in PK-deficiencies. The results support the idea of a single origin of most of the individual PK-mutations.
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Affiliation(s)
- C Lenzner
- Institute of Biochemistry, Faculty of Medicine, Humboldt-University Berlin, Charité, Germany
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Molecular Analysis of 29 Pyruvate Kinase–Deficient Patients From Central Europe With Hereditary Hemolytic Anemia. Blood 1997. [DOI: 10.1182/blood.v89.5.1793.1793_1793_1799] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We investigated the DNA of 29 unrelated pyruvate kinase (PK) deficiency (PKD) patients from Central Europe with hereditary nonspherocytic hemolytic anemia for mutations in the PK-L/R gene. Among 58 potentially affected alleles, 53 mutations were identified, of which 17 were different from each other. Of these 17 mutations, 13 were single-nucleotide (nt) substitutions resulting in amino acid exchanges, G787A (Gly263-Arg), G994A (Gly332-Ser), G1006T (Ala336-Ser), G1010A (Arg337-Gln), A1081G (Asn361-Asp), G1127T (Ser376-Ile), G1174A (Ala392-Thr), G1281T (Glu427-Asp), C1454T (Ser485-Phe), C1456T (Arg486-Trp), G1493A (Arg498-His), G1529A (Arg510-Gln), and C1594T (Arg532-Trp); 1 in-frame triplet deletion, 1060delAAG (delLys354); 1 in-frame triplet insertion, 1203insAGC (insSer after Cys401); 1 splicesite mutation, 101-1G-A; and 1 frameshift deletion, 628delGT. Six mutations, 628delGT, G787A, G1010A, G1127T, G1281T, and C1454T, are described for the first time. To test the hypothesis of a single origin of the most common PK mutation in the European population, G1529A, we investigated all patients at four polymorphic sites in the PK-L/R gene: C/A at nt 1705, C/T at nt 1992, the (ATT)n microsatellite in intron J, and a polymorphism (T)10/(T)19 in intron I. Nine patients homozygous for mutation G1529A were consistent in all four markers. In the group of patients homozygous for mutation G1529A, the hematologic parameters and clinical manifestations have been studied in detail. Although having an identical mutation in the PK-L/R gene, the patients are affected differently. Their appearance ranges from a very mild compensated hemolysis to a severe anemia. Possible molecular explanations are discussed.
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Molecular Analysis of 29 Pyruvate Kinase–Deficient Patients From Central Europe With Hereditary Hemolytic Anemia. Blood 1997. [DOI: 10.1182/blood.v89.5.1793] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
We investigated the DNA of 29 unrelated pyruvate kinase (PK) deficiency (PKD) patients from Central Europe with hereditary nonspherocytic hemolytic anemia for mutations in the PK-L/R gene. Among 58 potentially affected alleles, 53 mutations were identified, of which 17 were different from each other. Of these 17 mutations, 13 were single-nucleotide (nt) substitutions resulting in amino acid exchanges, G787A (Gly263-Arg), G994A (Gly332-Ser), G1006T (Ala336-Ser), G1010A (Arg337-Gln), A1081G (Asn361-Asp), G1127T (Ser376-Ile), G1174A (Ala392-Thr), G1281T (Glu427-Asp), C1454T (Ser485-Phe), C1456T (Arg486-Trp), G1493A (Arg498-His), G1529A (Arg510-Gln), and C1594T (Arg532-Trp); 1 in-frame triplet deletion, 1060delAAG (delLys354); 1 in-frame triplet insertion, 1203insAGC (insSer after Cys401); 1 splicesite mutation, 101-1G-A; and 1 frameshift deletion, 628delGT. Six mutations, 628delGT, G787A, G1010A, G1127T, G1281T, and C1454T, are described for the first time. To test the hypothesis of a single origin of the most common PK mutation in the European population, G1529A, we investigated all patients at four polymorphic sites in the PK-L/R gene: C/A at nt 1705, C/T at nt 1992, the (ATT)n microsatellite in intron J, and a polymorphism (T)10/(T)19 in intron I. Nine patients homozygous for mutation G1529A were consistent in all four markers. In the group of patients homozygous for mutation G1529A, the hematologic parameters and clinical manifestations have been studied in detail. Although having an identical mutation in the PK-L/R gene, the patients are affected differently. Their appearance ranges from a very mild compensated hemolysis to a severe anemia. Possible molecular explanations are discussed.
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36
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Miwa S, Fujii H. Molecular basis of erythroenzymopathies associated with hereditary hemolytic anemia: tabulation of mutant enzymes. Am J Hematol 1996; 51:122-32. [PMID: 8579052 DOI: 10.1002/(sici)1096-8652(199602)51:2<122::aid-ajh5>3.0.co;2-#] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Molecular abnormalities of erythroenzymopathies associated with hereditary hemolytic anemia have been determined by means of molecular biology. Pyruvate kinase (PK) deficiency is the most common and well-characterized enzyme deficiency in the glycolytic pathway, and it causes hereditary hemolytic anemia. To date, 47 gene mutations have been identified. We identified one base deletion, one splicing mutation, and six distinct missense mutations in 12 unrelated families with a homozygous PK deficiency. Mutations located near the substrate or fructose-1,6- diphosphate binding site may change the conformation of the active site, resulting in a drastic loss of activity and severe clinical symptoms. Glucose-6-phosphate dehydrogenase (G6PD)deficiency is the most common metabolic disorder, and it is associated with chronic hemolytic anemia and/or drug- or infection-induced acute hemolytic attack. An estimated 400 million people are affected worldwide. The mutations responsible for about 78 variants have been determined. Some have polymorphic frequencies in different populations. Most variants are produced by one or two nucleotide substitutions. Molecular studies have disclosed that most of the class 1 G6PD variants associated with chronic hemolysis have the mutations surrounding either the substrate or the NADP binding site. Among rare enzymopathies, missense mutations have been determined in deficiencies of glucosephosphate isomerase, (TPI), phosphoglycerate kinase, and adenylate kinase. Compound heterozygosity with missense mutation and base deletion has been determined in deficiencies of hexokinase and diphosphoglyceromutase. Compound heterozygosity with missense and nonsense mutations has been identified in TPI deficiency. One base junction mutations resulting in abnormally spliced PFK-M mRNA have been identified in homozygous PFK deficiency. An exception is hemolytic anemia due to increased adenosine deaminase activity. The basic abnormality appears to result from the overproduction of a structurally normal enzyme.
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Affiliation(s)
- S Miwa
- Okinawa Memorial Institute for Medical Research, Tokyo Women's Medical College, Japan
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