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Sizaret D, Tallegas M, de Pinieux G. Granulome central à cellules géantes des maxillaires bilatéral dans le cadre d’un syndrome de Noonan : à propos d’un cas avec mise au point sur les lésions osseuses riches en cellules géantes des maxillaires. Ann Pathol 2022; 42:259-263. [DOI: 10.1016/j.annpat.2022.01.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 01/04/2022] [Indexed: 12/11/2022]
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2
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Sigamani V, Rajasingh S, Gurusamy N, Panda A, Rajasingh J. In-Silico and In-Vitro Analysis of Human SOS1 Protein Causing Noonan Syndrome - A Novel Approach to Explore the Molecular Pathways. Curr Genomics 2021; 22:526-540. [PMID: 35386434 PMCID: PMC8905634 DOI: 10.2174/1389202922666211130144221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 11/02/2021] [Accepted: 11/03/2021] [Indexed: 11/22/2022] Open
Abstract
Aims Perform in-silico analysis of human SOS1 mutations to elucidate their pathogenic role in Noonan syndrome (NS). Background NS is an autosomal dominant genetic disorder caused by single nucleotide mutation in PTPN11, SOS1, RAF1, and KRAS genes. NS is thought to affect approximately 1 in 1000. NS patients suffer different pathogenic effects depending on the mutations they carry. Analysis of the mutations would be a promising predictor in identifying the pathogenic effect of NS. Methods We performed computational analysis of the SOS1 gene to identify the pathogenic nonsynonymous single nucleotide polymorphisms (nsSNPs) th a t cause NS. SOS1 variants were retrieved from the SNP database (dbSNP) and analyzed by in-silico tools I-Mutant, iPTREESTAB, and MutPred to elucidate their structural and functional characteristics. Results We found that 11 nsSNPs of SOS1 that were linked to NS. 3D modeling of the wild-type and the 11 nsSNPs of SOS1 showed that SOS1 interacts with cardiac proteins GATA4, TNNT2, and ACTN2. We also found that GRB2 and HRAS act as intermediate molecules between SOS1 and cardiac proteins. Our in-silico analysis findings were further validated using induced cardiomyocytes (iCMCs) derived from NS patients carrying SOS1 gene variant c.1654A>G (NSiCMCs) and compared to control human skin fibroblast-derived iCMCs (C-iCMCs). Our in vitro data confirmed that the SOS1, GRB2 and HRAS gene expressions as well as the activated ERK protein, were significantly decreased in NS-iCMCs when compared to C-iCMCs. Conclusion This is the first in-silico and in vitro study demonstrating that 11 nsSNPs of SOS1 play deleterious pathogenic roles in causing NS.
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Affiliation(s)
- Vinoth Sigamani
- Department of Bioscience Research, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Sheeja Rajasingh
- Department of Bioscience Research, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Narasimman Gurusamy
- Department of Bioscience Research, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Arunima Panda
- Department of Genetic Engineering, SRM Institute of Science and Technology, Chennai, India
| | - Johnson Rajasingh
- Department of Bioscience Research, University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Medicine-Cardiology, University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Microbiology, Immunology & Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee
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3
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Billar RJ, Manoubi W, Kant SG, Wijnen RMH, Demirdas S, Schnater JM. Association between pectus excavatum and congenital genetic disorders: A systematic review and practical guide for the treating physician. J Pediatr Surg 2021; 56:2239-2252. [PMID: 34039477 DOI: 10.1016/j.jpedsurg.2021.04.016] [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: 11/24/2020] [Revised: 04/13/2021] [Accepted: 04/18/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Pectus excavatum (PE) could be part of a genetic disorder, which then has implications regarding comorbidity, the surgical correction of PE, and reproductive choices. However, referral of a patient presenting with PE for genetic analysis is often delayed because additional crucial clinical signs may be subtle or even missed in syndromic patients. We reviewed the literature to inventory known genetic disorders associated with PE and create a standardized protocol for clinical evaluation. METHODS A systematic literature search was performed in electronic databases. Genetic disorders were considered associated with PE if studies reported at least five cases with PE. Characteristics of each genetic disorder were extracted from the literature and the OMIM database in order to create a practical guide for the clinician. RESULTS After removal of duplicates from the initial search, 1632 citations remained. Eventually, we included 119 full text articles, representing 20 different genetic disorders. Relevant characteristics and important clinical signs of each genetic disorder were summarized providing a standardized protocol in the form of a scoring list. The most important clinical sign was a positive family history for PE and/or congenital heart defect. CONCLUSIONS Twenty unique genetic disorders have been found associated with PE. We have created a scoring list for the clinician that systematically evaluates crucial clinical signs, thereby facilitating decision making for referral to a clinical geneticist.
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Affiliation(s)
- Ryan J Billar
- Erasmus University Medical Center - Sophia Children's Hospital, department of Paediatric Surgery Rotterdam, Netherlands
| | - Wiem Manoubi
- Erasmus University Medical Centre, department of Neuroscience, Rotterdam, Netherlands
| | - Sarina G Kant
- Erasmus University Medical Centre, department of Clinical Genetics, Rotterdam, Netherlands
| | - René M H Wijnen
- Erasmus University Medical Center - Sophia Children's Hospital, department of Paediatric Surgery Rotterdam, Netherlands
| | - Serwet Demirdas
- Erasmus University Medical Centre, department of Clinical Genetics, Rotterdam, Netherlands
| | - Johannes M Schnater
- Erasmus University Medical Center - Sophia Children's Hospital, department of Paediatric Surgery Rotterdam, Netherlands.
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4
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Schreuder WH, van der Wal JE, de Lange J, van den Berg H. Multiple versus solitary giant cell lesions of the jaw: Similar or distinct entities? Bone 2021; 149:115935. [PMID: 33771761 DOI: 10.1016/j.bone.2021.115935] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 02/27/2021] [Accepted: 03/17/2021] [Indexed: 02/06/2023]
Abstract
The majority of giant cell lesions of the jaw present as a solitary focus of disease in bones of the maxillofacial skeleton. Less frequently they occur as multifocal lesions. This raises the clinical dilemma if these should be considered distinct entities and therefore each need a specific therapeutic approach. Solitary giant cell lesions of the jaw present with a great diversity of symptoms. Recent molecular analysis revealed that these are associated with somatic gain-of-function mutations in KRAS, FGFR1 or TRPV4 in a large component of the mononuclear stromal cells which all act on the RAS/MAPK pathway. For multifocal lesions, a small group of neoplastic multifocal giant cell lesions of the jaw remain after ruling out hyperparathyroidism. Strikingly, most of these patients are diagnosed with jaw lesions before the age of 20 years, thus before the completion of dental and jaw development. These multifocal lesions are often accompanied by a diagnosis or strong clinical suspicion of a syndrome. Many of the frequently reported syndromes belong to the so-called RASopathies, with germline or mosaic mutations leading to downstream upregulation of the RAS/MAPK pathway. The other frequently reported syndrome is cherubism, with gain-of-function mutations in the SH3BP2 gene leading through assumed and unknown signaling to an autoinflammatory bone disorder with hyperactive osteoclasts and defective osteoblastogenesis. Based on this extensive literature review, a RAS/MAPK pathway activation is hypothesized in all giant cell lesions of the jaw. The different interaction between and contribution of deregulated signaling in individual cell lineages and crosstalk with other pathways among the different germline- and non-germline-based alterations causing giant cell lesions of the jaw can be explanatory for the characteristic clinical features. As such, this might also aid in the understanding of the age-dependent symptomatology of syndrome associated giant cell lesions of the jaw; hopefully guiding ideal timing when installing treatment strategies in the future.
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Affiliation(s)
- Willem H Schreuder
- Department of Oral and Maxillofacial Surgery, Amsterdam UMC and Academic Center for Dentistry Amsterdam, University of Amsterdam, Amsterdam, the Netherlands; Department of Head and Neck Surgery and Oncology, Antoni van Leeuwenhoek / Netherlands Cancer Institute, Amsterdam, the Netherlands.
| | - Jacqueline E van der Wal
- Department of Pathology, Antoni van Leeuwenhoek / Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Jan de Lange
- Department of Oral and Maxillofacial Surgery, Amsterdam UMC and Academic Center for Dentistry Amsterdam, University of Amsterdam, Amsterdam, the Netherlands
| | - Henk van den Berg
- Department of Pediatrics / Oncology, Amsterdam UMC, University of Amsterdam, Emma Children's Hospital, Amsterdam, the Netherlands
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5
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Friedrich RE, Zustin J, Luebke AM, Rosenbaum T, Gosau M, Hagel C, Kohlrusch FK, Wieland I, Zenker M. Neurofibromatosis Type 1 With Cherubism-like Phenotype, Multiple Osteolytic Bone Lesions of Lower Extremities, and Alagille-syndrome: Case Report With Literature Survey. In Vivo 2021; 35:1711-1736. [PMID: 33910856 DOI: 10.21873/invivo.12431] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/17/2021] [Accepted: 03/18/2021] [Indexed: 01/18/2023]
Abstract
BACKGROUND/AIM Neurofibromatosis type 1 (NF) is an autosomal dominant hereditary disease. The cardinal clinical findings include characteristic skeletal alterations. Difficulties in diagnosis and therapy can arise if an individual has further illnesses. CASE REPORT This is a case report of a 16-year-old patient affected by NF1. She also suffered from Alagille syndrome and the consequences of fetal alcohol exposure. The patient's facial phenotype showed findings that could be assigned to one or more of the known diseases. The patient was referred for treating a cherubism-like recurrent central giant cell granuloma (CGCG) of the jaw. The patient developed bilateral, multilocular non-ossifying fibromas (NOF) of the long bones of the lower extremity. Treatment of the skeletal lesions consisted of local curettage. While NOF regressed after surgery, the CGCG of the jaw remained largely unchanged. Extensive genetic tests confirmed a previously unknown germline mutation in the JAG1 gene, the germline mutation of the NF1 gene, and the somatic mutation in the NF1 gene in the diffuse plexiform neurofibroma, but not in the CGCG. CONCLUSION Assigning facial findings to a defined syndrome is ambiguous in many cases and especially difficult in patients who have multiple diseases that can affect the facial phenotype. Surgical therapy should be adapted to the individual findings.
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Affiliation(s)
- Reinhard E Friedrich
- Oral and Craniomaxillofacial Surgery, Eppendorf University Hospital, University of Hamburg, Hamburg, Germany;
| | - Jozef Zustin
- Institute of Osteology and Biomechanics, Eppendorf University Hospital, University of Hamburg, Hamburg, Germany.,Institute of Pathology, Gemeinschaftspraxis Pathologie-Regensburg, Regensburg, Germany
| | - Andreas M Luebke
- Institute of Pathology, Eppendorf University Hospital, University of Hamburg, Hamburg, Germany
| | | | - Martin Gosau
- Oral and Craniomaxillofacial Surgery, Eppendorf University Hospital, University of Hamburg, Hamburg, Germany
| | - Christian Hagel
- Institute of Neuropathology, Eppendorf University Hospital, University of Hamburg, Hamburg, Germany
| | - Felix K Kohlrusch
- Oral and Craniomaxillofacial Surgery, Eppendorf University Hospital, University of Hamburg, Hamburg, Germany
| | - Ilse Wieland
- Institute of Human Genetics, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - Martin Zenker
- Institute of Human Genetics, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
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6
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Baltanás FC, Zarich N, Rojas-Cabañeros JM, Santos E. SOS GEFs in health and disease. Biochim Biophys Acta Rev Cancer 2020; 1874:188445. [PMID: 33035641 DOI: 10.1016/j.bbcan.2020.188445] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/01/2020] [Accepted: 10/01/2020] [Indexed: 12/11/2022]
Abstract
SOS1 and SOS2 are the most universal and widely expressed family of guanine exchange factors (GEFs) capable or activating RAS or RAC1 proteins in metazoan cells. SOS proteins contain a sequence of modular domains that are responsible for different intramolecular and intermolecular interactions modulating mechanisms of self-inhibition, allosteric activation and intracellular homeostasis. Despite their homology, analyses of SOS1/2-KO mice demonstrate functional prevalence of SOS1 over SOS2 in cellular processes including proliferation, migration, inflammation or maintenance of intracellular redox homeostasis, although some functional redundancy cannot be excluded, particularly at the organismal level. Specific SOS1 gain-of-function mutations have been identified in inherited RASopathies and various sporadic human cancers. SOS1 depletion reduces tumorigenesis mediated by RAS or RAC1 in mouse models and is associated with increased intracellular oxidative stress and mitochondrial dysfunction. Since WT RAS is essential for development of RAS-mutant tumors, the SOS GEFs may be considered as relevant biomarkers or therapy targets in RAS-dependent cancers. Inhibitors blocking SOS expression, intrinsic GEF activity, or productive SOS protein-protein interactions with cellular regulators and/or RAS/RAC targets have been recently developed and shown preclinical and clinical effectiveness blocking aberrant RAS signaling in RAS-driven and RTK-driven tumors.
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Affiliation(s)
- Fernando C Baltanás
- Centro de Investigación del Cáncer - IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Natasha Zarich
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Jose M Rojas-Cabañeros
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Eugenio Santos
- Centro de Investigación del Cáncer - IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007 Salamanca, Spain.
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7
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Rodríguez FA, Castellón L, Moreno R, Paez E, Aracena Álvarez MI. Noonan syndrome with multiple Giant cell lesions, management and treatment with surgery and interferon alpha-2a therapy: Case report. Birth Defects Res 2020; 112:732-739. [PMID: 32065515 DOI: 10.1002/bdr2.1659] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 02/06/2020] [Indexed: 01/08/2023]
Abstract
We report the case of a 14-year-old girl that was referred to the maxillo facial surgery unit at age 11 years because she exhibited swelling in the right side of her maxilla and right mandible. After a conservative surgery, she started with interferon alpha-2a to avoid recurrence. She has remained in treatment with successful results during her follow up. Considerable reduction of both maxilla and mandible lesions and bone fill have been documented. In addition, her clinical history and phenotype were suggestive of Noonan syndrome. She has short stature, broad and short neck; hypertelorism (increased distance between the eyes); downslanting palpebral fissures; sparse eyebrows and eyelashes; posteriorly rotated ears with fleshy lobes; follicular keratosis over the face, and developmental delay. Her karyotype was 46, XX. Molecular analysis of RAS/MAPK pathway genes showed a SOS1 amino acid substitution of arginine to lysine at position 552 (p.R552K). This case presents the infrequent condition of Noonan syndrome with multiple giant cell lesions (NS/MGCL) that would be the first patient as far as we know treated with surgery and interferon alpha-2a for her giant cell lesions.
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Affiliation(s)
| | - Loreto Castellón
- Maxillofacial Unit, Hospital Dr. Luis Calvo Mackenna, Santiago, Chile
| | - Regina Moreno
- Unidad de Genética, Genética - Clínica Alemana, Temuco, Chile
| | - Eduardo Paez
- Hemato - Oncology Unit, Hospital Dr. Hernán Henríquez Aravena, Temuco, Chile
| | - Mariana Inés Aracena Álvarez
- Unit of Genetics and Metabolic diseases, Division of Pediatrics, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.,Unit of Genetics, Hospital Dr. Luis Calvo Mackenna, Santiago, Chile
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8
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Marino A, Tirelli F, Giani T, Cimaz R. Periodic fever syndromes and the autoinflammatory diseases (AIDs). J Transl Autoimmun 2019; 3:100031. [PMID: 32743516 PMCID: PMC7388371 DOI: 10.1016/j.jtauto.2019.100031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 12/13/2019] [Accepted: 12/13/2019] [Indexed: 12/14/2022] Open
Abstract
Innate immune system represents the ancestral defense against infectious agents preserved along the evolution and species; it is phylogenetically older than the adaptive immune system, which exists only in the vertebrates. Cells with phagocytic activity such as neutrophils, macrophages, and natural killer (NK) cells play a key role in innate immunity. In 1999 Kastner et al. first introduced the term “autoinflammation” describing two diseases characterized by recurrent episodes of systemic inflammation without any identifiable infectious trigger: Familial Mediterranean Fever (FMF) and TNF Receptor Associated Periodic Syndrome (TRAPS). Autoinflammatory diseases (AIDs) are caused by self-directed inflammation due to an alteration of innate immunity leading to systemic inflammatory attacks typically in an on/off mode. In addition to inflammasomopathies, nuclear factor (NF)-κB-mediated disorders (also known as Rhelopathies) and type 1 interferonopathies are subjects of more recent studies. This review aims to provide an overview of the field with the most recent updates (see “Most recent developments in..” paragraphs) and a description of the newly identified AIDs. Autoinflammatory diseases are caused by self-directed inflammation. Alteration of innate immunity leads to systemic inflammation attacks. The autoinflammatory field is exponentially expanding. The advances in AIDs have led to new insights into immune system understanding. Autoimmunity and autoinflammation features may be simultaneously present.
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Affiliation(s)
- Achille Marino
- Department of Pediatrics, Desio Hospital, ASST Monza, Desio, MB, Italy.,Biomedical Sciences, University of Florence, Florence, Italy
| | - Francesca Tirelli
- Rheumatology Unit, Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Teresa Giani
- Rheumatology Unit, Meyer Children's Hospital, University of Florence, Florence, Italy.,Department of Medical Biotechnology, University of Siena, Siena, Italy
| | - Rolando Cimaz
- Department of Clinical Sciences and Community Health, University of Milano, Milan, Italy
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9
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Bessis D, Miquel J, Bourrat E, Chiaverini C, Morice-Picard F, Abadie C, Manna F, Baumann C, Best M, Blanchet P, Bursztejn AC, Capri Y, Coubes C, Giuliano F, Guillaumont S, Hadj-Rabia S, Jacquemont ML, Jeandel C, Lacombe D, Mallet S, Mazereeuw-Hautier J, Molinari N, Pallure V, Pernet C, Philip N, Pinson L, Sarda P, Sigaudy S, Vial Y, Willems M, Geneviève D, Verloes A, Cavé H. Dermatological manifestations in Noonan syndrome: a prospective multicentric study of 129 patients positive for mutation. Br J Dermatol 2019; 180:1438-1448. [PMID: 30417923 DOI: 10.1111/bjd.17404] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/27/2018] [Indexed: 01/08/2023]
Abstract
BACKGROUND Data on dermatological manifestations of Noonan syndrome (NS) remain heterogeneous and are based on limited dermatological expertise. OBJECTIVES To describe the dermatological manifestations of NS, compare them with the literature findings, and test for dermatological phenotype-genotype correlations with or without the presence of PTPN11 mutations. METHODS We performed a large 4-year, prospective, multicentric, collaborative dermatological and genetic study. RESULTS Overall, 129 patients with NS were enrolled, including 65 patients with PTPN11-NS, 34 patients with PTPN11-NS with multiple lentigines (NSML), and 30 patients with NS who had a mutation other than PTPN11. Easy bruising was the most frequent dermatological finding in PTPN11-NS, present in 53·8% of patients. Multiple lentigines and café-au-lait macules (n ≥ 3) were present in 94% and 80% of cases of NSML linked to specific mutations of PTPN11, respectively. Atypical forms of NSML could be associated with NS with RAF1 or NRAS mutations. In univariate analysis, patients without a PTPN11 mutation showed (i) a significantly higher frequency of keratinization disorders (P = 0·001), including keratosis pilaris (P = 0·005), ulerythema ophryogenes (P = 0·0001) and palmar and/or plantar hyperkeratosis (P = 0·06, trend association), and (ii) a significantly higher frequency of scarce scalp hair (P = 0·035) and scarce or absent eyelashes (P = 0·06, trend association) than those with PTPN11 mutations. CONCLUSIONS The cutaneous phenotype of NS with a PTPN11 mutation is generally mild and nonspecific, whereas the absence of a PTPN11 mutation is associated with a high frequency of keratinization disorders and hair abnormalities.
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Affiliation(s)
- D Bessis
- Department of Dermatology, Saint-Eloi Hospital, Competence Centre for Rare Skin Diseases, Montpellier, France.,University of Montpellier, Montpellier, France.,INSERM U1058, Montpellier, France
| | - J Miquel
- Department of Paediatric Dermatology, Femme-Mère-Enfant Hospital, University of South Réunion, Saint-Pierre Réunion, France.,Department of Dermatology, University of Rennes, Rennes, France
| | - E Bourrat
- Department of Paediatric Dermatology, Robert-Debré Hospital, AP-HP, Paris, France
| | - C Chiaverini
- Department of Dermatology, L'Archet 2 Hospital, Nice, France.,University of Nice, Nice, France
| | - F Morice-Picard
- Department of Paediatric Dermatology, Pellegrin University Hospital of Bordeaux, Bordeaux, France
| | - C Abadie
- Department of Clinical Genetics, Sud Hospital, Rennes, France.,University Hospital of Rennes, Rennes, France
| | - F Manna
- University of Montpellier, Montpellier, France.,Department of Medical Information, Epidemiological and Clinical Research Unit, La Colombière Hospital, Montpellier, France
| | - C Baumann
- Department of Clinical Genetics, Robert-Debré Hospital, AP-HP, Paris, France.,University of Paris-Diderot, Paris, France
| | - M Best
- Department of Dermatology, Saint-Eloi Hospital, Competence Centre for Rare Skin Diseases, Montpellier, France.,University of Montpellier, Montpellier, France
| | - P Blanchet
- Department of Clinical Genetics, Arnaud de Villeneuve Hospital, Montpellier, France
| | - A-C Bursztejn
- Department of Dermatology, Brabois Hospital, Nancy, France.,University of Nancy, Nancy, France
| | - Y Capri
- Department of Clinical Genetics, Robert-Debré Hospital, AP-HP, Paris, France.,University of Paris-Diderot, Paris, France
| | - C Coubes
- Department of Clinical Genetics, Arnaud de Villeneuve Hospital, Montpellier, France
| | - F Giuliano
- University of Nice, Nice, France.,Department of Clinical Genetics, L'Archet 2 Hospital, Nice, France
| | - S Guillaumont
- University of Montpellier, Montpellier, France.,Department of Paediatric Cardiology, Arnaud de Villeneuve Hospital, Montpellier, France
| | - S Hadj-Rabia
- Department of Paediatric Dermatology, Reference Centre for Rare Skin Diseases, Necker-Enfants Malades Hospital, AP-HP, Paris, France
| | - M-L Jacquemont
- Department of Clinical Genetics, Femme-Mère-Enfant Hospital, University of South Réunion, Saint-Pierre Réunion, France
| | - C Jeandel
- University of Montpellier, Montpellier, France.,Department of Paediatric Endocrinology, Arnaud de Villeneuve Hospital, Montpellier, France
| | - D Lacombe
- Department of Clinical Genetics, Pellegrin University Hospital of Bordeaux, AP-HP, Paris, France
| | - S Mallet
- Department of Dermatology, La Timone Hospital, AP-HM, Marseille, France.,University of Marseille, Marseille, France
| | - J Mazereeuw-Hautier
- Department of Dermatology, Larrey Hospital, Reference Centre for Rare Skin Diseases, Toulouse, France.,University of Toulouse, Toulouse, France
| | - N Molinari
- University of Montpellier, Montpellier, France.,Department of Medical Information, Epidemiological and Clinical Research Unit, La Colombière Hospital, Montpellier, France
| | - V Pallure
- Department of Dermatology, CH, Perpignan, Perpignan, France
| | - C Pernet
- Department of Dermatology, Saint-Eloi Hospital, Competence Centre for Rare Skin Diseases, Montpellier, France
| | - N Philip
- University of Marseille, Marseille, France.,Department of Clinical Genetics, La Timone Hospital, AP-HM, Marseille, France
| | - L Pinson
- Department of Clinical Genetics, Arnaud de Villeneuve Hospital, Montpellier, France
| | - P Sarda
- Department of Clinical Genetics, Arnaud de Villeneuve Hospital, Montpellier, France
| | - S Sigaudy
- University of Marseille, Marseille, France.,Department of Clinical Genetics, La Timone Hospital, AP-HM, Marseille, France
| | - Y Vial
- University of Paris-Diderot, Paris, France.,Department of Genetic Biochemistry, Robert-Debré Hospital, AP-HP, Paris, France
| | - M Willems
- Department of Clinical Genetics, Arnaud de Villeneuve Hospital, Montpellier, France
| | - D Geneviève
- Department of Clinical Genetics, Arnaud de Villeneuve Hospital, Montpellier, France.,INSERM U1183, Montpellier, France
| | - A Verloes
- Department of Clinical Genetics, Robert-Debré Hospital, AP-HP, Paris, France.,University of Paris-Diderot, Paris, France
| | - H Cavé
- University of Paris-Diderot, Paris, France.,Department of Genetic Biochemistry, Robert-Debré Hospital, AP-HP, Paris, France
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10
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Multifocal Pigmented Villonodular Synovitis in the Noonan Syndrome. Case Rep Orthop 2018; 2018:7698052. [PMID: 30631623 PMCID: PMC6305014 DOI: 10.1155/2018/7698052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 10/24/2018] [Accepted: 11/25/2018] [Indexed: 11/24/2022] Open
Abstract
Noonan-like/multiple giant cell lesion (NS/MGCL) is a rare condition overlapping with Noonan syndrome. Once thought to be a specific and separate entity, it is now suggested to be a variant of the Noonan syndrome spectrum. We report the case of an 8-year-old boy with a typical clinical picture of Noonan syndrome with a de novo germline mutation of PTPN11 (c.854 T>C). During his follow-up, the patient developed multifocal pigmented villonodular synovitis which first affected the left knee and shortly after both elbows.
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11
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Acute lymphoblastic leukemia in the context of RASopathies. Eur J Med Genet 2016; 59:173-8. [PMID: 26855057 DOI: 10.1016/j.ejmg.2016.01.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 01/13/2016] [Indexed: 12/29/2022]
Abstract
Noonan syndrome is associated with a range of malignancies including acute lymphoblastic leukemia (ALL). However, little information is available regarding the frequency, natural history, characteristics and prognosis of ALL in Noonan syndrome or RASopathies in general. Cross-referencing data from a large prospective cohort of 1176 patients having a molecularly confirmed RASopathy with data from the French childhood cancer registry allowed us to identify ALL in 6 (0.5%) patients including 4/778 (0.5%) with a germline PTPN11 mutation and 2/94 (2.1%) with a germline SOS1 mutation. None of the patients of our series with CFC syndrome (with germline BRAF or MAP2K1/MAP2K2 mutation - n = 121) or Costello syndrome (with HRAS mutation - n = 35) had an ALL. A total of 19 Noonan-ALL were gathered by adding our patients to those of the International Berlin-Munster-Frankfurt (I-BFM) study group and previously reported patients. Strikingly, all Noonan-associated ALL were B-cell precursor ALL, and high hyperdiploidy with more than 50 chromosomes was found in the leukemia cells of 13/17 (76%) patients with available genetics data. Our data suggest that children with Noonan syndrome are at higher risk to develop ALL. Like what is observed for somatic PTPN11 mutations, NS is preferentially associated with the development of hyperdiploid ALL that will usually respond well to chemotherapy. However, Noonan syndrome patients seem to have a propensity to develop post therapy myelodysplasia that can eventually be fatal. Hence, one should be particularly cautious when treating these patients.
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Louati R, Abdelmoula NB, Trabelsi I, Abid D, Lissewski C, Kharrat N, Kamoun S, Zenker M, Rebai T. Clinical and Molecular Findings of Tunisian Patients with RASopathies. Mol Syndromol 2014; 5:212-7. [PMID: 25337068 DOI: 10.1159/000362898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/25/2014] [Indexed: 11/19/2022] Open
Abstract
Noonan syndrome (NS) and related disorders, which are now summarized under the term RASopathies, are caused by germline mutations in genes encoding protein components of the Ras/mitogen-activated protein kinase pathway. In this study, we evaluated the clinical and molecular spectrum of 21 Tunisian patients, recruited by a cardiology unit, for whom RASopathy diagnosis was suspected by clinical geneticists. Overall, 19 patients had a clinical diagnosis of NS and 2 were classified as having Cardiofaciocutaneous (CFC) syndrome. In 52% (n = 11) of patients, a RASopathy has been molecularly confirmed. Mutations in PTPN11 and SOS1 genes were found in patients with diagnosis of NS and BRAF gene mutations in patients with CFC syndrome. As reported from other cohorts, mutations in exons 3 and 8 of the PTPN11 gene predominated in Tunisian NS patients. A very uncommon PTPN11 mutation c.5C>T (p.T2I), the functional consequences of which have so far remained unclear, was identified in one patient. As biased by the mode of recruitment, all patients included in this study had a congenital heart defect, with pulmonary valve stenosis being the most frequent one. Short stature and developmental abnormalities were present in mutation-positive cases. This is the first molecular study in patients from southern Tunisia with RASopathy diagnosis.
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Affiliation(s)
- Rim Louati
- Department of Histology, Medical University of Sfax, Center of Biotechnology of Sfax, Sfax, Tunisia
| | - N Bouayed Abdelmoula
- Department of Histology, Medical University of Sfax, Center of Biotechnology of Sfax, Sfax, Tunisia
| | - Imen Trabelsi
- Cardiology Service, Hedi Chaker Hospital, Center of Biotechnology of Sfax, Sfax, Tunisia
| | - Dorra Abid
- Cardiology Service, Hedi Chaker Hospital, Center of Biotechnology of Sfax, Sfax, Tunisia
| | - Christina Lissewski
- Institute of Human Genetics, University Hospital Magdeburg, Magdeburg, Germany
| | - Najla Kharrat
- Laboratory of Microorganisms and Biomolecules, Center of Biotechnology of Sfax, Sfax, Tunisia
| | - Samir Kamoun
- Cardiology Service, Hedi Chaker Hospital, Center of Biotechnology of Sfax, Sfax, Tunisia
| | - Martin Zenker
- Institute of Human Genetics, University Hospital Magdeburg, Magdeburg, Germany
| | - Tarek Rebai
- Department of Histology, Medical University of Sfax, Center of Biotechnology of Sfax, Sfax, Tunisia
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Hedrich CM, Hahn G, Girschick HJ, Morbach H. A clinical and pathomechanistic profile of chronic nonbacterial osteomyelitis/chronic recurrent multifocal osteomyelitis and challenges facing the field. Expert Rev Clin Immunol 2014; 9:845-54. [DOI: 10.1586/1744666x.2013.824670] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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14
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Abstract
Noonan syndrome is a genetic multisystem disorder characterised by distinctive facial features, developmental delay, learning difficulties, short stature, congenital heart disease, renal anomalies, lymphatic malformations, and bleeding difficulties. Mutations that cause Noonan syndrome alter genes encoding proteins with roles in the RAS-MAPK pathway, leading to pathway dysregulation. Management guidelines have been developed. Several clinically relevant genotype-phenotype correlations aid risk assessment and patient management. Increased understanding of the pathophysiology of the disease could help development of pharmacogenetic treatments.
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Affiliation(s)
- Amy E Roberts
- Department of Cardiology and Division of Genetics, Children's Hospital Boston, Boston, MA 02115, USA.
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15
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Morbach H, Hedrich CM, Beer M, Girschick HJ. Autoinflammatory bone disorders. Clin Immunol 2013; 147:185-96. [PMID: 23369460 DOI: 10.1016/j.clim.2012.12.012] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 12/15/2012] [Accepted: 12/18/2012] [Indexed: 12/18/2022]
Abstract
Autoinflammatory bone disorders are characterized by chronic non-infectious osteomyelitis and inflammation-induced bone resorption and result from aberrant activation of the innate immune system. Sporadic chronic non-bacterial osteomyelitis (CNO) is the most common disease subtype. The clinical picture is highly variable and the exact underlying pathophysiology remains to be determined. Recently, novel insights in the pathophysiology of sterile bone inflammation have been gathered by analyzing patients with rare, monogenic inflammatory diseases. In this overview CNO and Majeed syndrome, cherubism, hypophosphatasia and primary hypertrophic osteoarthropathy will be discussed. For the latter four disorders, a genetic cause affecting bone metabolism and leading to chronic bone inflammation has been described. The exact pathophysiology of CNO remains to be determined. Insights from monogenic autoinflammatory bone diseases and the identification of distinct inflammatory pathways may help to understand the pathogenesis of bone inflammation and inflammation-induced bone resorption in more common diseases.
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Affiliation(s)
- Henner Morbach
- Department of Pediatrics, University of Würzburg, Würzburg, Germany
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Karbach J, Coerdt W, Wagner W, Bartsch O. Case report: Noonan syndrome with multiple giant cell lesions and review of the literature. Am J Med Genet A 2012; 158A:2283-9. [DOI: 10.1002/ajmg.a.35493] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 05/07/2012] [Indexed: 02/02/2023]
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17
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Reichenberger EJ, Levine MA, Olsen BR, Papadaki ME, Lietman SA. The role of SH3BP2 in the pathophysiology of cherubism. Orphanet J Rare Dis 2012; 7 Suppl 1:S5. [PMID: 22640988 PMCID: PMC3359958 DOI: 10.1186/1750-1172-7-s1-s5] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Cherubism is a rare bone dysplasia that is characterized by symmetrical bone resorption limited to the jaws. Bone lesions are filled with soft fibrous giant cell-rich tissue that can expand and cause severe facial deformity. The disorder typically begins in children at ages of 2-5 years and the bone resorption and facial swelling continues until puberty; in most cases the lesions regress spontaneously thereafter. Most patients with cherubism have germline mutations in the gene encoding SH3BP2, an adapter protein involved in adaptive and innate immune response signaling. A mouse model carrying a Pro416Arg mutation in SH3BP2 develops osteopenia and expansile lytic lesions in bone and some soft tissue organs. In this review we discuss the genetics of cherubism, the biological functions of SH3BP2 and the analysis of the mouse model. The data suggest that the underlying cause for cherubism is a systemic autoinflammatory response to physiologic challenges despite the localized appearance of bone resorption and fibrous expansion to the jaws in humans.
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Affiliation(s)
- Ernst J Reichenberger
- Department of Reconstructive Sciences, Center for Regenerative Medicine and Skeletal Development, University of Connecticut Health Center, Farmington, CT, USA.
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18
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Woo SB. Nonodontogenic Intraosseous Lesions. ORAL PATHOLOGY 2012:382-431. [DOI: 10.1016/b978-1-4377-2226-0.00016-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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19
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Lepri F, De Luca A, Stella L, Rossi C, Baldassarre G, Pantaleoni F, Cordeddu V, Williams BJ, Dentici ML, Caputo V, Venanzi S, Bonaguro M, Kavamura I, Faienza MF, Pilotta A, Stanzial F, Faravelli F, Gabrielli O, Marino B, Neri G, Silengo MC, Ferrero GB, Torrrente I, Selicorni A, Mazzanti L, Digilio MC, Zampino G, Dallapiccola B, Gelb BD, Tartaglia M. SOS1 mutations in Noonan syndrome: molecular spectrum, structural insights on pathogenic effects, and genotype-phenotype correlations. Hum Mutat 2011; 32:760-72. [PMID: 21387466 PMCID: PMC3118925 DOI: 10.1002/humu.21492] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 02/23/2011] [Indexed: 01/03/2023]
Abstract
Noonan syndrome (NS) is among the most common nonchromosomal disorders affecting development and growth. NS is caused by aberrant RAS-MAPK signaling and is genetically heterogeneous, which explains, in part, the marked clinical variability documented for this Mendelian trait. Recently, we and others identified SOS1 as a major gene underlying NS. Here, we explored further the spectrum of SOS1 mutations and their associated phenotypic features. Mutation scanning of the entire SOS1 coding sequence allowed the identification of 33 different variants deemed to be of pathological significance, including 16 novel missense changes and in-frame indels. Various mutation clusters destabilizing or altering orientation of regions of the protein predicted to contribute structurally to the maintenance of autoinhibition were identified. Two previously unappreciated clusters predicted to enhance SOS1's recruitment to the plasma membrane, thus promoting a spatial reorientation of domains contributing to inhibition, were also recognized. Genotype–phenotype analysis confirmed our previous observations, establishing a high frequency of ectodermal anomalies and a low prevalence of cognitive impairment and reduced growth. Finally, mutation analysis performed on cohorts of individuals with nonsyndromic pulmonic stenosis, atrial septal defects, and ventricular septal defects excluded a major contribution of germline SOS1 lesions to the isolated occurrence of these cardiac anomalies. Hum Mutat 32:760–772, 2011. © 2011 Wiley-Liss, Inc.
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Affiliation(s)
- Francesca Lepri
- IRCCS Casa Sollievo della Sofferenza, Laboratorio Mendel, San Giovanni Rotondo, Italy
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Tartaglia M, Gelb BD. Disorders of dysregulated signal traffic through the RAS-MAPK pathway: phenotypic spectrum and molecular mechanisms. Ann N Y Acad Sci 2010; 1214:99-121. [PMID: 20958325 PMCID: PMC3010252 DOI: 10.1111/j.1749-6632.2010.05790.x] [Citation(s) in RCA: 153] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
RAS GTPases control a major signaling network implicated in several cellular functions, including cell fate determination, proliferation, survival, differentiation, migration, and senescence. Within this network, signal flow through the RAF-MEK-ERK pathway-the first identified mitogen-associated protein kinase (MAPK) cascade-mediates early and late developmental processes controlling morphology determination, organogenesis, synaptic plasticity, and growth. Signaling through the RAS-MAPK cascade is tightly controlled; and its enhanced activation represents a well-known event in oncogenesis. Unexpectedly, in the past few years, inherited dysregulation of this pathway has been recognized as the cause underlying a group of clinically related disorders sharing facial dysmorphism, cardiac defects, reduced postnatal growth, ectodermal anomalies, variable cognitive deficits, and susceptibility to certain malignancies as major features. These disorders are caused by heterozygosity for mutations in genes encoding RAS proteins, regulators of RAS function, modulators of RAS interaction with effectors, or downstream signal transducers. Here, we provide an overview of the phenotypic spectrum associated with germline mutations perturbing RAS-MAPK signaling, the unpredicted molecular mechanisms converging toward the dysregulation of this signaling cascade, and major genotype-phenotype correlations.
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Affiliation(s)
- Marco Tartaglia
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, Italy.
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21
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Bufalino A, Carrera M, Carlos R, Coletta RD. Giant cell lesions in noonan syndrome: case report and review of the literature. Head Neck Pathol 2010; 4:174-7. [PMID: 20383758 PMCID: PMC2878618 DOI: 10.1007/s12105-010-0178-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Accepted: 03/31/2010] [Indexed: 11/24/2022]
Abstract
Noonan-like/multiple giant cell lesion syndrome (NS/MGCLS) is a rare condition with phenotypic overlap with Noonan syndrome (NS). Once thought to be a specific and separate entity, it is now suggested to be a variant of the NS spectrum. We report a patient with classical cardinal features of NS, including short stature, mild ptosis, hypertelorism, down-slating palpebral fissures, low-set and posteriorly angulated ears, short neck, pectus excavatum, widely spaced nipples and cryptochidism, which were associated with bilateral central giant cell lesions in the mandible and germ-line mutation (C218T, Thr73Ile) in the exon 3 of the PTPN11 gene. The similar clinical and genetic aspects support the observation that NS/MGCLS is a variant of NS and giant cell lesions are an integrant part of this disorder.
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Affiliation(s)
- Andreia Bufalino
- Department of Oral Diagnosis, Dental School, State University of Campinas, Av. Limeira, 901, Piracicaba, São Paulo 13414-018 Brazil
| | - Manoela Carrera
- Department of Oral Diagnosis, Dental School, State University of Campinas, Av. Limeira, 901, Piracicaba, São Paulo 13414-018 Brazil
| | - Roman Carlos
- Centro Clínico de Cabeza y Cuello and Hospital Herrera Llerandi, Guatemala City, Guatemala
| | - Ricardo D. Coletta
- Department of Oral Diagnosis, Dental School, State University of Campinas, Av. Limeira, 901, Piracicaba, São Paulo 13414-018 Brazil
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22
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Flanagan AM, Delaney D, O'Donnell P. Benefits of molecular pathology in the diagnosis of musculoskeletal disease : Part II of a two-part review: bone tumors and metabolic disorders. Skeletal Radiol 2010; 39:213-24. [PMID: 19669759 DOI: 10.1007/s00256-009-0758-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Accepted: 07/08/2009] [Indexed: 02/02/2023]
Abstract
The second part of this review, on the benefits of molecular pathology in the diagnosis disease, focuses on the genetics of bone tumors and metabolic disease. Unlike soft tissue tumors, the number of currently exploitable molecular abnormalities for diagnosing bone neoplasms is small, although the same gene rearrangements are found in primitive neuroectodermal tumor/Ewing sarcoma in both skeletal and extraskeletal sites. Compared with soft tissue tumors, genetic abnormalities, which are valuable to diagnosticians in skeletal disease, are often germline and post-zygotic aberrations rather than somatic translocations. In addition, the review highlights the range of disease entities classified as "osteoclast-rich lesions," some of which harbor germline mutations. It also addresses the importance of phosphate metabolism in skeletal disorders including phosphaturic mesenchymal tumor, vitamin D-resistant rickets, and tumoral calcinosis.
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Affiliation(s)
- Adrienne M Flanagan
- Department of Histopathology, Royal National Orthopaedic Hospital NHS Trust, Stanmore, Middlesex, HA7 4LP, UK.
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23
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Tartaglia M, Zampino G, Gelb BD. Noonan syndrome: clinical aspects and molecular pathogenesis. Mol Syndromol 2010; 1:2-26. [PMID: 20648242 DOI: 10.1159/000276766] [Citation(s) in RCA: 156] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Accepted: 10/30/2009] [Indexed: 01/20/2023] Open
Abstract
Noonan syndrome (NS) is a relatively common, clinically variable and genetically heterogeneous developmental disorder characterized by postnatally reduced growth, distinctive facial dysmorphism, cardiac defects and variable cognitive deficits. Other associated features include ectodermal and skeletal defects, cryptorchidism, lymphatic dysplasias, bleeding tendency, and, rarely, predisposition to hematologic malignancies during childhood. NS is caused by mutations in the PTPN11, SOS1, KRAS, RAF1, BRAF and MEK1 (MAP2K1) genes, accounting for approximately 70% of affected individuals. SHP2 (encoded by PTPN11), SOS1, BRAF, RAF1 and MEK1 positively contribute to RAS-MAPK signaling, and possess complex autoinhibitory mechanisms that are impaired by mutations. Similarly, reduced GTPase activity or increased guanine nucleotide release underlie the aberrant signal flow through the MAPK cascade promoted by most KRAS mutations. More recently, a single missense mutation in SHOC2, which encodes a cytoplasmic scaffold positively controlling RAF1 activation, has been discovered to cause a closely related phenotype previously termed Noonan-like syndrome with loose anagen hair. This mutation promotes aberrantly acquired N-myristoylation of the protein, resulting in its constitutive targeting to the plasma membrane and dysregulated function. PTPN11, BRAF and RAF1 mutations also account for approximately 95% of LEOPARD syndrome, a condition which resembles NS phenotypically but is characterized by multiple lentigines dispersed throughout the body, café-au-lait spots, and a higher prevalence of electrocardiographic conduction abnormalities, obstructive cardiomyopathy and sensorineural hearing deficits. These recent discoveries demonstrate that the substantial phenotypic variation characterizing NS and related conditions can be ascribed, in part, to the gene mutated and even the specific molecular lesion involved.
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Affiliation(s)
- M Tartaglia
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, Italy
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