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Starosta RT, Lee AJ, Toolan ER, He M, Wongkittichote P, Daniel EJP, Radenkovic S, Budhraja R, Pandey A, Sharma J, Morava E, Nguyen H, Dickson PI. D-mannose as a new therapy for fucokinase deficiency-related congenital disorder of glycosylation (FCSK-CDG). Mol Genet Metab 2024; 142:108488. [PMID: 38735264 DOI: 10.1016/j.ymgme.2024.108488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Revised: 04/22/2024] [Accepted: 05/02/2024] [Indexed: 05/14/2024]
Abstract
INTRODUCTION Fucokinase deficiency-related congenital disorder of glycosylation (FCSK-CDG) is a rare autosomal recessive inborn error of metabolism characterized by a decreased flux through the salvage pathway of GDP-fucose biosynthesis due to a block in the recycling of L-fucose that exits the lysosome. FCSK-CDG has been described in 5 individuals to date in the medical literature, with a phenotype comprising global developmental delays/intellectual disability, hypotonia, abnormal myelination, posterior ocular disease, growth and feeding failure, immune deficiency, and chronic diarrhea, without clear therapeutic recommendations. PATIENT AND METHODS In a so far unreported FCSK-CDG patient, we studied proteomics and glycoproteomics in vitro in patient-derived fibroblasts and also performed in vivo glycomics, before and after treatment with either D-Mannose or L-Fucose. RESULTS We observed a marked increase in fucosylation after D-mannose supplementation in fibroblasts compared to treatment with L-Fucose. The patient was then treated with D-mannose at 850 mg/kg/d, with resolution of the chronic diarrhea, resolution of oral aversion, improved weight gain, and observed developmental gains. Serum N-glycan profiles showed an improvement in the abundance of fucosylated glycans after treatment. No treatment-attributed adverse effects were observed. CONCLUSION D-mannose is a promising new treatment for FCSK-CDG.
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Affiliation(s)
- Rodrigo Tzovenos Starosta
- Division of Medical Genetics and Genomics, Washington University School of Medicine, St. Louis, MO, USA; Division of Clinical Genetics and Metabolism, University of Colorado Anschutz, Aurora, CO, USA; Graduate Program in Science: Gastroenterology and Hepatology, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | - Angela J Lee
- Division of Medical Genetics and Genomics, Washington University School of Medicine, St. Louis, MO, USA
| | - Elizabeth R Toolan
- Division of Medical Genetics and Genomics, Washington University School of Medicine, St. Louis, MO, USA
| | - Miao He
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Parith Wongkittichote
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA; Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Earnest James Paul Daniel
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | | | - Rohit Budhraja
- Department of Pathology and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA
| | - Akhilesh Pandey
- Department of Pathology and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA
| | - Jaiprakash Sharma
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - Eva Morava
- Department of Clinical Genomics, Mayo Clinic, Rochester, MN, USA
| | - Hoanh Nguyen
- Division of Medical Genetics and Genomics, Washington University School of Medicine, St. Louis, MO, USA
| | - Patricia I Dickson
- Division of Medical Genetics and Genomics, Washington University School of Medicine, St. Louis, MO, USA
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Fazelzadeh Haghighi M, Jafari Khamirani H, Fallahi J, Monfared AA, Ashrafi Dehkordi K, Tabei SMB. Novel insight into FCSK-congenital disorder of glycosylation through a CRISPR-generated cell model. Mol Genet Genomic Med 2024; 12:e2445. [PMID: 38722107 PMCID: PMC11080630 DOI: 10.1002/mgg3.2445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 04/08/2024] [Accepted: 04/23/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND FCSK-congenital disorder of glycosylation (FCSK-CDG) is a recently discovered rare autosomal recessive genetic disorder with defective fucosylation due to mutations in the fucokinase encoding gene, FCSK. Despite the essential role of fucokinase in the fucose salvage pathway and severe multisystem manifestations of FCSK-CDG patients, it is not elucidated which cells or which types of fucosylation are affected by its deficiency. METHODS In this study, CRISPR/Cas9 was employed to construct an FCSK-CDG cell model and explore the molecular mechanisms of the disease by lectin flow cytometry and real-time PCR analyses. RESULTS Comparison of cellular fucosylation by lectin flow cytometry in the created CRISPR/Cas9 FCSK knockout and the same unedited cell lines showed no significant change in the amount of cell surface fucosylated glycans, which is consistent with the only documented previous study on different cell types. It suggests a probable effect of this disease on secretory glycoproteins. Investigating O-fucosylation by analysis of the NOTCH3 gene expression as a potential target revealed a significant decrease in the FCSK knockout cells compared with the same unedited ones, proving the effect of fucokinase deficiency on EGF-like repeats O-fucosylation. CONCLUSION This study expands insight into the FCSK-CDG molecular mechanism; to the best of our knowledge, it is the first research conducted to reveal a gene whose expression level alters due to this disease.
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Affiliation(s)
- Maryam Fazelzadeh Haghighi
- Department of Molecular Medicine, School of Advanced TechnologiesShahrekord University of Medical SciencesShahrekordIran
| | | | - Jafar Fallahi
- Molecular Medicine Department, School of Advanced Medical Sciences and TechnologiesShiraz University of Medical SciencesShirazIran
| | - Ali Arabi Monfared
- Central Research LaboratoryShiraz University of Medical SciencesShirazIran
| | - Korosh Ashrafi Dehkordi
- Department of Molecular Medicine, School of Advanced TechnologiesShahrekord University of Medical SciencesShahrekordIran
| | - Seyed Mohammad Bagher Tabei
- Department of Medical GeneticsShiraz University of Medical SciencesShirazIran
- Maternal‐Fetal Medicine Research CenterShiraz University of Medical SciencesShirazIran
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Scheper AF, Schofield J, Bohara R, Ritter T, Pandit A. Understanding glycosylation: Regulation through the metabolic flux of precursor pathways. Biotechnol Adv 2023; 67:108184. [PMID: 37290585 DOI: 10.1016/j.biotechadv.2023.108184] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 05/29/2023] [Accepted: 05/31/2023] [Indexed: 06/10/2023]
Abstract
Glycosylation is how proteins and lipids are modified with complex carbohydrates known as glycans. The post-translational modification of proteins with glycans is not a template-driven process in the same way as genetic transcription or protein translation. Glycosylation is instead dynamically regulated by metabolic flux. This metabolic flux is determined by the concentrations and activities of the glycotransferase enzymes, which synthesise glycans, the metabolites that act as their precursors and transporter proteins. This review provides an overview of the metabolic pathways underlying glycan synthesis. Pathological dysregulation of glycosylation, particularly increased glycosylation occurring during inflammation, is also elucidated. The resulting inflammatory hyperglycosylation acts as a glycosignature of disease, and we report on the changes in the metabolic pathways which feed into glycan synthesis, revealing alterations to key enzymes. Finally, we examine studies in developing metabolic inhibitors targeting these critical enzymes. These results provide the tools for researchers investigating the role of glycan metabolism in inflammation and have helped to identify promising glycotherapeutic approaches to inflammation.
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Affiliation(s)
- Aert F Scheper
- CÚRAM, SFI Research Centre for Medical Devices, University of Galway, Ireland
| | - Jack Schofield
- CÚRAM, SFI Research Centre for Medical Devices, University of Galway, Ireland
| | - Raghvendra Bohara
- CÚRAM, SFI Research Centre for Medical Devices, University of Galway, Ireland
| | - Thomas Ritter
- CÚRAM, SFI Research Centre for Medical Devices, University of Galway, Ireland; School of Medicine, University of Galway, Ireland; Regenerative Medicine Institute (REMEDI), University of Galway, Ireland
| | - Abhay Pandit
- CÚRAM, SFI Research Centre for Medical Devices, University of Galway, Ireland.
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Jin LW, di Lucente J, Mendiola UR, Tang X, Zivkovic AM, Lebrilla CB, Maezawa I. The role of FUT8-catalyzed core fucosylation in Alzheimer's amyloid-β oligomer-induced activation of human microglia. Glia 2023; 71:1346-1359. [PMID: 36692036 PMCID: PMC11021125 DOI: 10.1002/glia.24345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 01/03/2023] [Accepted: 01/10/2023] [Indexed: 01/25/2023]
Abstract
Fucosylation, especially core fucosylation of N-glycans catalyzed by α1-6 fucosyltransferase (fucosyltransferase 8 or FUT8), plays an important role in regulating the peripheral immune system and inflammation. However, its role in microglial activation is poorly understood. Here we used human induced pluripotent stem cells-derived microglia (hiMG) as a model to study the role of FUT8-catalyzed core fucosylation in amyloid-β oligomer (AβO)-induced microglial activation, in view of its significant relevance to the pathogenesis of Alzheimer's disease (AD). HiMG responded to AβO and lipopolysaccharides (LPS) with a pattern of pro-inflammatory activation as well as enhanced core fucosylation and FUT8 expression within 24 h. Furthermore, we found increased FUT8 expression in both human AD brains and microglia isolated from 5xFAD mice, a model of AD-like cerebral amyloidosis. Inhibition of fucosylation in AβO-stimulated hiMG reduced the induction of pro-inflammatory cytokines, suppressed the activation of p38MAPK, and rectified phagocytic deficits. Specific inhibition of FUT8 by siRNA-mediated knockdown also reduced AβO-induced pro-inflammatory cytokines. We further showed that p53 binds to the two consensus binding sites in the Fut8 promoter, and that p53 knockdown abolished FUT8 overexpression in AβO-activated hiMG. Taken together, our evidence supports that FUT8-catalyzed core fucosylation is a signaling pathway required for AβO-induced microglia activation and that FUT8 is a component of the p53 signaling cascade regulating microglial behavior. Because microglia are a key driver of AD pathogenesis, our results suggest that microglial FUT8 could be an anti-inflammatory therapeutic target for AD.
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Affiliation(s)
- Lee-Way Jin
- Department of Pathology and Laboratory Medicine and M.I.N.D. Institute, University of California Davis Medical Center, 2805 50 Street, Sacramento, CA 95817
| | - Jacopo di Lucente
- Department of Pathology and Laboratory Medicine and M.I.N.D. Institute, University of California Davis Medical Center, 2805 50 Street, Sacramento, CA 95817
| | - Ulises R. Mendiola
- Department of Pathology and Laboratory Medicine and M.I.N.D. Institute, University of California Davis Medical Center, 2805 50 Street, Sacramento, CA 95817
| | - Xinyu Tang
- Department of Nutrition, University of California, Davis, CA 95618
| | | | | | - Izumi Maezawa
- Department of Pathology and Laboratory Medicine and M.I.N.D. Institute, University of California Davis Medical Center, 2805 50 Street, Sacramento, CA 95817
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Lee HF, Chi CS. Congenital disorders of glycosylation and infantile epilepsy. Epilepsy Behav 2023; 142:109214. [PMID: 37086590 DOI: 10.1016/j.yebeh.2023.109214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 04/01/2023] [Accepted: 04/04/2023] [Indexed: 04/24/2023]
Abstract
Congenital disorders of glycosylation (CDG) are a group of rare inherited metabolic disorders caused by defects in various defects of protein or lipid glycosylation pathways. The symptoms and signs of CDG usually develop in infancy. Epilepsy is commonly observed in CDG individuals and is often a presenting symptom. These epilepsies can present across the lifespan, share features of refractoriness to antiseizure medications, and are often associated with comorbid developmental delay, psychomotor regression, intellectual disability, and behavioral problems. In this review, we discuss CDG and infantile epilepsy, focusing on an overview of clinical manifestations and electroencephalographic features. Finally, we propose a tiered approach that will permit a clinician to systematically investigate and identify CDG earlier, and furthermore, to provide genetic counseling for the family.
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Affiliation(s)
- Hsiu-Fen Lee
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, 145, Xingda Rd., Taichung 402, Taiwan; Division of Pediatric Neurology, Children's Medical Center, Taichung Veterans General Hospital, 1650, Taiwan Boulevard Sec. 4, Taichung 407, Taiwan.
| | - Ching-Shiang Chi
- Division of Pediatric Neurology, Children's Medical Center, Taichung Veterans General Hospital, 1650, Taiwan Boulevard Sec. 4, Taichung 407, Taiwan.
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Al Tuwaijri A, Alyafee Y, Umair M, Alsubait A, Alharbi M, AlEidi H, Ballow M, Aldrees M, Alam Q, Al Abdulrahman A, Alrifai MT, Alfadhel M. Congenital disorder of glycosylation with defective fucosylation 2 (
FCSK
gene defect): The third report in the literature with a mild phenotype. Mol Genet Genomic Med 2022; 11:e2117. [PMID: 36426412 PMCID: PMC10094070 DOI: 10.1002/mgg3.2117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 10/29/2022] [Accepted: 11/01/2022] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Congenital disorders of glycosylation (CDG) are a group of heterogeneous disorders caused by abnormal lipid or protein glycosylation. Variants in the FCSK gene have been reported to cause CDG. Defective FCSK-induced CDG (FCSK-CDG) has only been reported previously in three unrelated children. METHODS In this study, we genetically and clinically examined a 3-year-old proband with resolved infantile spasms and normal development. Standard whole-exome sequencing (WES) and Sanger sequencing were performed to identify the functional impact of the variant. RESULTS WES revealed a rare biallelic missense variant (c.3013G>C; p.Val1005Leu) in FCSK. RT-qPCR showed a significant depletion in FCSK gene expression in the affected individual. Western blotting revealed reduced FCSK expression at the protein level compared to that in the control. Furthermore, 3D protein modeling suggested changes in the secondary structure, which might affect the overall FCSK protein function. CONCLUSION This study broadens the mutation and phenotypic spectrum of FCSK-associated developmental disorders.
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Affiliation(s)
- Abeer Al Tuwaijri
- Medical Genomics Research Department King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG‐HA) Riyadh Saudi Arabia
- Clinical Laboratory Sciences Department College of Applied Medical Sciences, King Saud Bin Abdulaziz University for Health Sciences (KSAU‐HS) Riyadh Saudi Arabia
| | - Yusra Alyafee
- Medical Genomics Research Department King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
| | - Muhammad Umair
- Medical Genomics Research Department King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG‐HA) Riyadh Saudi Arabia
| | - Arwa Alsubait
- King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG‐HA) Riyadh Saudi Arabia
- Medical Research Core Facilities and Platforms King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
| | - Mashael Alharbi
- Medical Genomics Research Department King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG‐HA) Riyadh Saudi Arabia
| | - Hamad AlEidi
- Medical Genomics Research Department King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG‐HA) Riyadh Saudi Arabia
| | - Mariam Ballow
- Medical Genomics Research Department King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG‐HA) Riyadh Saudi Arabia
| | - Mohammed Aldrees
- Medical Genomics Research Department King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG‐HA) Riyadh Saudi Arabia
| | - Qamre Alam
- Medical Genomics Research Department King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG‐HA) Riyadh Saudi Arabia
| | - Abdulkareem Al Abdulrahman
- Medical Genomics Research Department King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG‐HA) Riyadh Saudi Arabia
| | - Muhammad Talal Alrifai
- Neurology Division, Department of Pediatrics King Abdulaziz Medical City, Ministry of National Guard Health Affairs (NGHA) Riyadh Saudi Arabia
| | - Majid Alfadhel
- Medical Genomics Research Department King Abdullah International Medical Research Center (KAIMRC) Riyadh Saudi Arabia
- King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG‐HA) Riyadh Saudi Arabia
- Genetics and Precision Medicine Department (GPM) King Abdullah Specialized Children's Hospital Riyadh Saudi Arabia
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Sosicka P, Ng BG, Freeze HH. Chemical Therapies for Congenital Disorders of Glycosylation. ACS Chem Biol 2022; 17:2962-2971. [PMID: 34788024 PMCID: PMC9126425 DOI: 10.1021/acschembio.1c00601] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Congenital disorders of glycosylation (CDG) are ultrarare, genetically and clinically heterogeneous metabolic disorders. Although the number of identified CDG is growing rapidly, there are few therapeutic options. Most treatments involve dietary supplementation with monosaccharides or other precursors. These approaches are relatively safe, but in many cases, the molecular and biochemical underpinnings are incomplete. Recent studies demonstrate that yeast, worm, fly, and zebrafish models of CDG are powerful tools in screening repurposed drugs, ushering a new avenue to search for novel therapeutic options. Here we present a perspective on compounds that are currently in use for CDG treatment or have a potential to be applied as therapeutics in the near future.
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Affiliation(s)
| | | | - Hudson H. Freeze
- Address correspondence to: Hudson H. Freeze, Professor of Glycobiology, Director, Human Genetics Program, Sanford Children's Health Research Center, Sanford-Burnham-Prebys Medical Discovery Institute, 10901 N. Torrey Pines Rd. La Jolla, CA 92037, , Phone: 858-646-3142
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Manoochehri J, Kamal N, Khamirani HJ, Zoghi S, Haghighi MF, Goodarzi HR, Bagher Tabei SM. A combination of two novels homozygous FCSK variants cause disorder of glycosylation with defective fucosylation: New patient and literature review. Eur J Med Genet 2022; 65:104535. [PMID: 35718084 DOI: 10.1016/j.ejmg.2022.104535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 04/04/2022] [Accepted: 06/05/2022] [Indexed: 11/26/2022]
Abstract
Pathogenic variants in FCSK cause Congenital Disorder of Glycosylation with Defective Fucosylation-2 (FCSK-CDG; MIM: 618,324). It is a rare autosomal recessive genetic disease caused by defects in the L-fucose kinase, which is necessary for the fucose salvage pathway. Herein, we report two novel variants in an Iranian patient, the fourth individual with FCSK-CDG described in the literature. Two homozygous variants in FCSK (rs376941268; NM_145059.3: c.379C > A, p. Leu127Met and rs543223292; NM_145059.3: c.394G > C, p. Asp132His) were identified in the proband. Sanger sequencing conducted on his unaffected parents revealed that they were heterozygous for the same variants. The proband, a four-and-a-half year old Iranian male born to consanguineous parents, manifested Intellectual disability, growth delay, ophthalmic abnormalities, seizures, speech disorder, and feeding difficulties.
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Affiliation(s)
- Jamal Manoochehri
- Department of Genetics, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran
| | - Neda Kamal
- Department of Medical Genetics, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Hossein Jafari Khamirani
- Department of Medical Genetics, Shiraz University of Medical Sciences, Shiraz, Iran; Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Sina Zoghi
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Maryam Fazelzadeh Haghighi
- Department of Molecular Medicine, School of Advanced Technologies, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Hamed Reza Goodarzi
- Department of Genetics, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran
| | - Seyed Mohammad Bagher Tabei
- Department of Genetics, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran; Department of Medical Genetics, Shiraz University of Medical Sciences, Shiraz, Iran; Maternal-fetal Medicine Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
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Özgün N, Şahin Y. A case with congenital disorder of glycosylation with defective fucosylation 2 and new mutation in FUK gene. Brain Dev 2022; 44:239-243. [PMID: 34802815 DOI: 10.1016/j.braindev.2021.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 11/02/2021] [Accepted: 11/03/2021] [Indexed: 10/19/2022]
Abstract
INTRODUCTION Congenital disorders of glycosylation (CDG) is a group of rare, hereditary, multisystem disorders, predominantly affecting nervous system. There are N- and O- types of glycosylation. Fucosylation, a form of N-glycosylation, involves many enzymes. Until today, type 1 and type 2 fucosylation defects were identified, having pathogenic variants in genes encoding α-1,6-fucosyltransferase and fucokinase enzymes, respectively. In this article, a patient with type 2 fucosylation defect will be presented, with hypotonia, developmental delay and blindness and a pathogenic variant that was previously described in two patients. METHOD Whole exome sequencing (WES) was performed, since the patient had no time to implement diagnostic algorithm for hypotonia etiology. RESULTS WES revealed a new pathogenic variant of homozygous c.993_1011del (p.Glu335Hisfs*55) frameshift variant of the FUK gene NM_145059 transcript. She had milder clinical manifestation than reported two patients. CONCLUSION Congenital Defect of Glycosylation should be considered when the clinical findings cannot be explained by other known diseases, particularly in patients with multisystemic, predominantly neurological involvement.
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Affiliation(s)
- Nezir Özgün
- Division of Child Neurology, ISU Liv Hospital, İstinye University Faculty of Medicine, İstanbul, Turkey.
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Hüllen A, Falkenstein K, Weigel C, Huidekoper H, Naumann-Bartsch N, Spenger J, Feichtinger RG, Schaefers J, Frenz S, Kotlarz D, Momen T, Khoshnevisan R, Riedhammer KM, Santer R, Herget T, Rennings A, Lefeber DJ, Mayr JA, Thiel C, Wortmann SB. Congenital disorders of glycosylation with defective fucosylation. J Inherit Metab Dis 2021; 44:1441-1452. [PMID: 34389986 DOI: 10.1002/jimd.12426] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 08/02/2021] [Accepted: 08/10/2021] [Indexed: 11/05/2022]
Abstract
Fucosylation is essential for intercellular and intracellular recognition, cell-cell interaction, fertilization, and inflammatory processes. Only five types of congenital disorders of glycosylation (CDG) related to an impaired fucosylation have been described to date: FUT8-CDG, FCSK-CDG, POFUT1-CDG SLC35C1-CDG, and the only recently described GFUS-CDG. This review summarizes the clinical findings of all hitherto known 25 patients affected with those defects with regard to their pathophysiology and genotype. In addition, we describe five new patients with novel variants in the SLC35C1 gene. Furthermore, we discuss the efficacy of fucose therapy approaches within the different defects.
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Affiliation(s)
- Andreas Hüllen
- Centre for Child and Adolescent Medicine, Department 1, University of Heidelberg, Heidelberg, Germany
| | - Kristina Falkenstein
- Centre for Child and Adolescent Medicine, Department 1, University of Heidelberg, Heidelberg, Germany
| | - Corina Weigel
- Department of Pediatrics and Adolescent Medicine, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Hidde Huidekoper
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Nora Naumann-Bartsch
- Department of Pediatrics and Adolescent Medicine, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Johannes Spenger
- University Children's Hospital, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), Salzburg, Austria
| | - René G Feichtinger
- University Children's Hospital, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), Salzburg, Austria
| | - Jacqueline Schaefers
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Stephanie Frenz
- Department of Pediatrics, Dr von Hauner Children's Hospital, University Hospital, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Daniel Kotlarz
- Department of Pediatrics, Dr von Hauner Children's Hospital, University Hospital, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Tooba Momen
- Department of Asthma, Allergy and Clinical Immunology, Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Razieh Khoshnevisan
- Department of Immunology, Medical Faculty, Isfahan University of Medical Sciences, Isfahan, Iran
- Acquired Immunodeficiency Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Korbinian M Riedhammer
- Institute of Human Genetics, Klinikum Rechts der Isar, School of Medicine, Technical University of Munich, Munich, Germany
- Department of Nephrology, Klinikum Rechts der Isar, School of Medicine, Technical University of Munich, Munich, Germany
| | - René Santer
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Theresia Herget
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Alexander Rennings
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Amalia Children's Hospital, Nijmegen, The Netherlands
| | - Dirk J Lefeber
- Department of Neurology, Translational Metabolic Laboratory, Donders Center for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Johannes A Mayr
- University Children's Hospital, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), Salzburg, Austria
| | - Christian Thiel
- Centre for Child and Adolescent Medicine, Department 1, University of Heidelberg, Heidelberg, Germany
| | - Saskia B Wortmann
- University Children's Hospital, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), Salzburg, Austria
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Amalia Children's Hospital, Nijmegen, The Netherlands
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Feichtinger RG, Hüllen A, Koller A, Kotzot D, Grote V, Rapp E, Hofbauer P, Brugger K, Thiel C, Mayr JA, Wortmann SB. A spoonful of L-fucose-an efficient therapy for GFUS-CDG, a new glycosylation disorder. EMBO Mol Med 2021; 13:e14332. [PMID: 34468083 PMCID: PMC8422078 DOI: 10.15252/emmm.202114332] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 07/26/2021] [Accepted: 07/28/2021] [Indexed: 12/29/2022] Open
Abstract
Congenital disorders of glycosylation are a genetically and phenotypically heterogeneous family of diseases affecting the co- and posttranslational modification of proteins. Using exome sequencing, we detected biallelic variants in GFUS (NM_003313.4) c.[632G>A];[659C>T] (p.[Gly211Glu];[Ser220Leu]) in a patient presenting with global developmental delay, mild coarse facial features and faltering growth. GFUS encodes GDP-L-fucose synthase, the terminal enzyme in de novo synthesis of GDP-L-fucose, required for fucosylation of N- and O-glycans. We found reduced GFUS protein and decreased GDP-L-fucose levels leading to a general hypofucosylation determined in patient's glycoproteins in serum, leukocytes, thrombocytes and fibroblasts. Complementation of patient fibroblasts with wild-type GFUS cDNA restored fucosylation. Making use of the GDP-L-fucose salvage pathway, oral fucose supplementation normalized fucosylation of proteins within 4 weeks as measured in serum and leukocytes. During the follow-up of 19 months, a moderate improvement of growth was seen, as well as a clear improvement of cognitive skills as measured by the Kaufmann ABC and the Nijmegen Pediatric CDG Rating Scale. In conclusion, GFUS-CDG is a new glycosylation disorder for which oral L-fucose supplementation is promising.
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Affiliation(s)
- René G Feichtinger
- University Children’s HospitalSalzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU)SalzburgAustria
| | - Andreas Hüllen
- Department PediatricsCentre for Child and Adolescent MedicineUniversity of HeidelbergHeidelbergGermany
| | - Andreas Koller
- Research Program for Experimental OphthalmologyDepartment of Ophthalmology and OptometrySalzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU)SalzburgAustria
| | - Dieter Kotzot
- Clinical Genetics UnitSalzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU)SalzburgAustria
| | - Valerian Grote
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess EngineeringMagdeburgGermany
| | - Erdmann Rapp
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess EngineeringMagdeburgGermany
- glyXera GmbHMagdeburgGermany
| | - Peter Hofbauer
- Department of ProductionLandesapotheke SalzburgHospital PharmacySalzburgAustria
| | - Karin Brugger
- University Children’s HospitalSalzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU)SalzburgAustria
| | - Christian Thiel
- Department PediatricsCentre for Child and Adolescent MedicineUniversity of HeidelbergHeidelbergGermany
| | - Johannes A Mayr
- University Children’s HospitalSalzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU)SalzburgAustria
| | - Saskia B Wortmann
- University Children’s HospitalSalzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU)SalzburgAustria
- Department of PediatricsAmalia Children’s HospitalRadboud Center for Mitochondrial MedicineRadboudumcNijmegenThe Netherlands
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12
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Pajusalu S, Vals MA, Mihkla L, Šamarina U, Kahre T, Õunap K. The Estimated Prevalence of N-Linked Congenital Disorders of Glycosylation Across Various Populations Based on Allele Frequencies in General Population Databases. Front Genet 2021; 12:719437. [PMID: 34447415 PMCID: PMC8383291 DOI: 10.3389/fgene.2021.719437] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 07/21/2021] [Indexed: 01/16/2023] Open
Abstract
Congenital disorders of glycosylation (CDG) are a widely acknowledged group of metabolic diseases. PMM2-CDG is the most frequently diagnosed CDG with a prevalence as high as one in 20,000. In contrast, the prevalence of other CDG types remains unknown. This study aimed to analyze the estimated prevalence of different N-linked protein glycosylation disorders. We extracted allele frequencies for diverse populations from The Genome Aggregation Database (gnomAD), encompassing variant frequency information from 141,456 individuals. To identify pathogenic variants, we used the ClinVar database as a primary source. High confidence loss-of-function variants as defined by the LOFTEE algorithm were also classified as pathogenic. After summing up population frequencies for pathogenic alleles, estimated disease birth prevalence values with confidence intervals were calculated using the Bayesian method. We first validated our approach using two more common recessive disorders (cystic fibrosis and phenylketonuria) by showing that the estimated prevalences calculated from population allele frequencies were in accordance with previously published epidemiological studies. Among assessed 27 autosomal recessive N-glycosylation disorders, the only disease with estimated birth prevalence higher than one in 100,000 was PMM2-CDG (in both, all gnomAD individuals and those with European ancestry). The combined prevalence of 27 different N-glycosylation disorders was around one in 22,000 Europeans but varied considerably across populations. We will show estimated prevalence data from diverse populations and explain the possible pitfalls of this analysis. Still, we are confident that these data will guide CDG research and clinical care to identify CDG across populations.
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Affiliation(s)
- Sander Pajusalu
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia.,Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
| | - Mari-Anne Vals
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia.,Children's Clinic, Tartu University Hospital, Tartu, Estonia
| | - Laura Mihkla
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia.,Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
| | - Ustina Šamarina
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
| | - Tiina Kahre
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia.,Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
| | - Katrin Õunap
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia.,Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
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13
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L-Fucose treatment of FUT8-CDG. Mol Genet Metab Rep 2020; 25:100680. [PMID: 33312876 PMCID: PMC7719959 DOI: 10.1016/j.ymgmr.2020.100680] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 11/12/2020] [Accepted: 11/12/2020] [Indexed: 11/22/2022] Open
Abstract
FUT8-CDG is a severe multisystem disorder caused by mutations in FUT8, encoding the α-1,6-fucosyltransferase. We report on dizygotic twins with FUT8-CDG presenting with dysmorphisms, failure to thrive, and respiratory abnormalities. Due to the severe phenotype, oral L-fucose supplementation was started. Glycosylation analysis using mass spectrometry indicated a limited response to fucose therapy while the clinical presentation stabilized. Further research is needed to assess the concept of substrate supplementation in FUT8-CDG.
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14
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Advances in the evaluation and management of cortical/cerebral visual impairment in children. Surv Ophthalmol 2020; 65:708-724. [DOI: 10.1016/j.survophthal.2020.03.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 03/02/2020] [Accepted: 03/09/2020] [Indexed: 12/14/2022]
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15
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Ondruskova N, Cechova A, Hansikova H, Honzik T, Jaeken J. Congenital disorders of glycosylation: Still "hot" in 2020. Biochim Biophys Acta Gen Subj 2020; 1865:129751. [PMID: 32991969 DOI: 10.1016/j.bbagen.2020.129751] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/12/2020] [Accepted: 08/27/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Congenital disorders of glycosylation (CDG) are inherited metabolic diseases caused by defects in the genes important for the process of protein and lipid glycosylation. With the ever growing number of the known subtypes and discoveries regarding the disease mechanisms and therapy development, it remains a very active field of study. SCOPE OF REVIEW This review brings an update on the CDG-related research since 2017, describing the novel gene defects, pathobiomechanisms, biomarkers and the patients' phenotypes. We also summarize the clinical guidelines for the most prevalent disorders and the current therapeutical options for the treatable CDG. MAJOR CONCLUSIONS In the majority of the 23 new CDG, neurological involvement is associated with other organ disease. Increasingly, different aspects of cellular metabolism (e.g., autophagy) are found to be perturbed in multiple CDG. GENERAL SIGNIFICANCE This work highlights the recent trends in the CDG field and comprehensively overviews the up-to-date clinical recommendations.
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Affiliation(s)
- Nina Ondruskova
- Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Anna Cechova
- Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Hana Hansikova
- Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Tomas Honzik
- Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic.
| | - Jaak Jaeken
- Department of Paediatrics and Centre for Metabolic Diseases, KU Leuven and University Hospital Leuven, Leuven, Belgium.
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16
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Abstract
In this review, we focus on the metabolism of mammalian glycan-associated monosaccharides, where the vast majority of our current knowledge comes from research done during the 1960s and 1970s. Most monosaccharides enter the cell using distinct, often tissue specific transporters from the SLC2A family. If not catabolized, these monosaccharides can be activated to donor nucleotide sugars and used for glycan synthesis. Apart from exogenous and dietary sources, all monosaccharides and their associated nucleotide sugars can be synthesized de novo, using mostly glucose to produce all nine nucleotide sugars present in human cells. Today, monosaccharides are used as treatment options for a small number of rare genetic disorders and even some common conditions. Here, we cover therapeutic applications of these sugars and highlight biochemical gaps that must be revisited as we go forward.
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Affiliation(s)
- Paulina Sosicka
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, United States
| | - Bobby G. Ng
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, United States
| | - Hudson H. Freeze
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, United States
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17
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Pascoal C, Francisco R, Ferro T, Dos Reis Ferreira V, Jaeken J, Videira PA. CDG and immune response: From bedside to bench and back. J Inherit Metab Dis 2020; 43:90-124. [PMID: 31095764 DOI: 10.1002/jimd.12126] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 05/13/2019] [Accepted: 05/15/2019] [Indexed: 12/20/2022]
Abstract
Glycosylation is an essential biological process that adds structural and functional diversity to cells and molecules, participating in physiological processes such as immunity. The immune response is driven and modulated by protein-attached glycans that mediate cell-cell interactions, pathogen recognition and cell activation. Therefore, abnormal glycosylation can be associated with deranged immune responses. Within human diseases presenting immunological defects are congenital disorders of glycosylation (CDG), a family of around 130 rare and complex genetic diseases. In this review, we have identified 23 CDG with immunological involvement, characterized by an increased propensity to-often life-threatening-infection. Inflammatory and autoimmune complications were found in 7 CDG types. CDG natural history(ies) and the mechanisms behind the immunological anomalies are still poorly understood. However, in some cases, alterations in pathogen recognition and intracellular signaling (eg, TGF-β1, NFAT, and NF-κB) have been suggested. Targeted therapies to restore immune defects are only available for PGM3-CDG and SLC35C1-CDG. Fostering research on glycoimmunology may elucidate the involved pathophysiological mechanisms and open new therapeutic avenues, thus improving CDG patients' quality of life.
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Affiliation(s)
- Carlota Pascoal
- Portuguese Association for CDG, Lisbon, Portugal
- CDG & Allies - Professionals and Patient Associations International Network (CDG & Allies - PPAIN), Caparica, Portugal
- UCIBIO, Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Rita Francisco
- Portuguese Association for CDG, Lisbon, Portugal
- CDG & Allies - Professionals and Patient Associations International Network (CDG & Allies - PPAIN), Caparica, Portugal
- UCIBIO, Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Tiago Ferro
- CDG & Allies - Professionals and Patient Associations International Network (CDG & Allies - PPAIN), Caparica, Portugal
- UCIBIO, Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Vanessa Dos Reis Ferreira
- Portuguese Association for CDG, Lisbon, Portugal
- CDG & Allies - Professionals and Patient Associations International Network (CDG & Allies - PPAIN), Caparica, Portugal
| | - Jaak Jaeken
- CDG & Allies - Professionals and Patient Associations International Network (CDG & Allies - PPAIN), Caparica, Portugal
- Center for Metabolic Diseases, Department of Development and Regeneration, UZ and KU Leuven, Leuven, Belgium
| | - Paula A Videira
- Portuguese Association for CDG, Lisbon, Portugal
- CDG & Allies - Professionals and Patient Associations International Network (CDG & Allies - PPAIN), Caparica, Portugal
- UCIBIO, Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
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18
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Keeley TS, Yang S, Lau E. The Diverse Contributions of Fucose Linkages in Cancer. Cancers (Basel) 2019; 11:E1241. [PMID: 31450600 PMCID: PMC6769556 DOI: 10.3390/cancers11091241] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 08/12/2019] [Accepted: 08/20/2019] [Indexed: 12/17/2022] Open
Abstract
Fucosylation is a post-translational modification of glycans, proteins, and lipids that is responsible for many biological processes. Fucose conjugation via α(1,2), α(1,3), α(1,4), α(1,6), and O'- linkages to glycans, and variations in fucosylation linkages, has important implications for cancer biology. This review focuses on the roles that fucosylation plays in cancer, specifically through modulation of cell surface proteins and signaling pathways. How L-fucose and serum fucosylation patterns might be used for future clinical diagnostic, prognostic, and therapeutic approaches will be discussed.
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Affiliation(s)
- Tyler S Keeley
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA 17033, USA
- University of South Florida Cancer Biology Graduate Program, Tampa, FL 33602, USA
- Department of Tumor Biology, H. Lee Moffitt Cancer Center, Tampa, FL 33602, USA
| | - Shengyu Yang
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA 17033, USA.
| | - Eric Lau
- Department of Tumor Biology, H. Lee Moffitt Cancer Center, Tampa, FL 33602, USA.
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