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Perl AL, Pokorny JL, Green KJ. Desmosomes at a glance. J Cell Sci 2024; 137:jcs261899. [PMID: 38940346 PMCID: PMC11234380 DOI: 10.1242/jcs.261899] [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] [Indexed: 06/29/2024] Open
Abstract
Desmosomes are relatives of ancient cadherin-based junctions, which emerged late in evolution to ensure the structural integrity of vertebrate tissues by coupling the intermediate filament cytoskeleton to cell-cell junctions. Their ability to dynamically counter the contractile forces generated by actin-associated adherens junctions is particularly important in tissues under high mechanical stress, such as the skin and heart. Much more than the simple cellular 'spot welds' depicted in textbooks, desmosomes are in fact dynamic structures that can sense and respond to changes in their mechanical environment and external stressors like ultraviolet light and pathogens. These environmental signals are transmitted intracellularly via desmosome-dependent mechanochemical pathways that drive the physiological processes of morphogenesis and differentiation. This Cell Science at a Glance article and the accompanying poster review desmosome structure and assembly, highlight recent insights into how desmosomes integrate chemical and mechanical signaling in the epidermis, and discuss desmosomes as targets in human disease.
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Affiliation(s)
- Abbey L. Perl
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Jenny L. Pokorny
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Kathleen J. Green
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL 60611, USA
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2
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Friedrich RE, Rutkowski R, Gosau M. Multiple central giant cell granuloma of the jaws: diagnostic signposts of Noonan syndrome and RASopathy. Oral Maxillofac Surg 2024; 28:991-997. [PMID: 38347383 PMCID: PMC11144677 DOI: 10.1007/s10006-024-01209-2] [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: 07/12/2023] [Accepted: 01/07/2024] [Indexed: 06/04/2024]
Abstract
Noonan syndrome (NS) is a phenotypically variable inherited multi-system disorder. Maxillofacial findings can be diagnostic, especially in the evaluation of discrete facial dysmorphia. Diagnostic landmark findings of therapeutic relevance for the jaws such as central giant cell granuloma (CGCG) are rare in NS. However, recent molecular genetic studies indicate that these rare, benign lesions are neoplasms and more common in specific syndromes grouped under the umbrella term RASopathies. A specialist surgical diagnosis can be helpful in identifying the underlying disease. This report outlines diagnosis and treatment of a case of CGCG for which jaw diagnosis became the key to identifying a syndromic disease.
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Affiliation(s)
- Reinhard E Friedrich
- Department of Oral and Craniomaxillofacial Surgery, Eppendorf University Hospital, University of Hamburg, 20246, Hamburg, Germany.
| | - Rico Rutkowski
- Department of Oral and Craniomaxillofacial Surgery, Eppendorf University Hospital, University of Hamburg, 20246, Hamburg, Germany
| | - Martin Gosau
- Department of Oral and Craniomaxillofacial Surgery, Eppendorf University Hospital, University of Hamburg, 20246, Hamburg, Germany
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3
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Makhamreh MM, Shivashankar K, Araji S, Critchlow E, O'Brien BM, Wodoslawsky S, Berger SI, Al-Kouatly HB. RASopathies are the most common set of monogenic syndromes identified by exome sequencing for nonimmune hydrops fetalis: A systematic review and meta-analysis. Am J Med Genet A 2024; 194:e63494. [PMID: 38156365 DOI: 10.1002/ajmg.a.63494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 11/16/2023] [Accepted: 11/22/2023] [Indexed: 12/30/2023]
Abstract
RASopathies are a group of malformation syndromes known to lead to nonimmune hydrops fetalis (NIHF) in severe presentations. Pathogenic variants can be de novo or parentally inherited. Despite being a known frequent presentation, the fraction of monogenic NIHF cases due to RASopathies is limited in the literature. Also, the specific parental contribution of RASopathies to NIHF is not well described. Our objective was to review pooled exome sequencing (ES) diagnostic yield of RASopathies for NIHF and to determine the parental contribution of RASopathy to NIHF. We performed a systematic review of prenatal ES studies from January 1, 2000 to August 1, 2022. Thirty-six studies met inclusion criteria. Cases with RASopathy gene variants were reviewed. NIHF cases were further classified as isolated or non-isolated. Thirty-six ES studies including 46 pregnancies with NIHF and a diagnosed RASopathy were reviewed. Forty-four diagnostic variants and 2 variants of uncertain significance in 12 RASopathy genes were identified. Expanding on what was previously published, a total of 506 NIHF cases were extracted with 191 cases yielding a positive diagnosis by ES. The overall rate of RASopathy diagnosis in clinically diagnosed NIHF cases was 9% (44/506). The rate of RASopathy diagnosis among NIHF cases with positive genetic diagnosis by ES was 23% (44/191). Of the 46 cases identified, 13 (28%) variants were parentally inherited; specifically, 5/13 (38%) maternal, 3/13 (23%) paternal, 2/13 (15%) biparental, and 3/13 (23%) unspecified. Majority of NIHF cases 29/46 (63%) were isolated. Among NIHF cases with positive ES diagnoses, RASopathy diagnostic yield by ES was 23%. NIHF secondary to RASopathies was parentally inherited in 28% of cases. Most cases of NIHF due to RASopathy were isolated, with no prenatal detection of associated anomalies.
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Affiliation(s)
- Mona M Makhamreh
- Department of Obstetrics and Gynecology, Maimonides Medical Center, Brooklyn, New York, USA
| | - Kavya Shivashankar
- Department of Obstetrics and Gynecology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Sarah Araji
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Mississippi, Jackson, Mississippi, USA
| | - Elizabeth Critchlow
- Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Barbara M O'Brien
- Department of Obstetrics and Gynecology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
- Department Obstetrics, Gynecology, and Reproductive Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - Sascha Wodoslawsky
- Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Seth I Berger
- Center for Genetic Medicine Research and Rare Disease Institute, Children's National Medical Center, Washington, DC, USA
| | - Huda B Al-Kouatly
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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4
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Torrado C, Camaño M, Hindi N, Ortega J, Sevillano AR, Civantos G, Moura DS, Dimino A, Martín-Broto J. Antiangiogenics in Malignant Granular Cell Tumors: Review of the Literature. Cancers (Basel) 2023; 15:5187. [PMID: 37958362 PMCID: PMC10650106 DOI: 10.3390/cancers15215187] [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: 09/06/2023] [Revised: 10/12/2023] [Accepted: 10/25/2023] [Indexed: 11/15/2023] Open
Abstract
Granular cell tumors (GCT) represent 0.5% of all soft tissue sarcomas (STS), and when metastatic, they exhibit aggressive behavior and determine limited survival. Metastatic GCTs are relatively chemo-resistant; however, there is growing evidence of the benefit of using pazopanib and other targeted therapies in this histology. This is a review of the role of pazopanib and other targeted therapies in the treatment of GCTs, along with some insights on pathology and molecular biology described in GCTs. From 256 articles found in our search, 10 case-report articles met the inclusion criteria. Pazopanib was the most employed systemic therapy. The median reported time on therapy with pazopanib was seven months. Eight out of ten patients (80%) experienced disease control with pazopanib, while four out of ten (40%) patients achieved an objective RECIST response. Molecular studies suggested that antitumoral effects of pazopanib in GCT might be due to a loss-of-function of ATP6AP1/2 genes which consequently enhance signaling through several molecular pathways, such as SFKs, STAT5a/b, and PDGFR-β. Other reported targeted therapies for malignant GCTs included pazopanib in combination with crizotinib, which showed disease control for four months in one patient, and a PI3K inhibitor which achieved disease control for nine months in another patient. Dasatinib and megestrol were ineffective in two other different patients. Pazopanib has been demonstrated to be active in advanced GCTs and may be considered as a preferable treatment option.
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Affiliation(s)
- Carlos Torrado
- Medical Oncology Department, University Hospital Virgen del Rocío, 41013 Sevilla, Spain;
| | - Melisa Camaño
- Medical Oncology Department, National Cancer Institute, 11600 Montevideo, Uruguay;
| | - Nadia Hindi
- Instituto de Investigacion Sanitaria Fundacion Jimenez Diaz (IIS/FJD), 28015 Madrid, Spain; (N.H.); (J.O.); (A.R.S.); (D.S.M.)
- Medical Oncology Department, Fundación Jimenez Diaz University Hospital, 28040 Madrid, Spain
- General de Villalba University Hospital, 28400 Madrid, Spain
| | - Justo Ortega
- Instituto de Investigacion Sanitaria Fundacion Jimenez Diaz (IIS/FJD), 28015 Madrid, Spain; (N.H.); (J.O.); (A.R.S.); (D.S.M.)
- Medical Oncology Department, Fundación Jimenez Diaz University Hospital, 28040 Madrid, Spain
- General de Villalba University Hospital, 28400 Madrid, Spain
| | - Alberto R. Sevillano
- Instituto de Investigacion Sanitaria Fundacion Jimenez Diaz (IIS/FJD), 28015 Madrid, Spain; (N.H.); (J.O.); (A.R.S.); (D.S.M.)
- Medical Oncology Department, Fundación Jimenez Diaz University Hospital, 28040 Madrid, Spain
- General de Villalba University Hospital, 28400 Madrid, Spain
| | - Gema Civantos
- Pathology Department, Hospital Virgen del Rocío, 41013 Sevilla, Spain;
| | - David S. Moura
- Instituto de Investigacion Sanitaria Fundacion Jimenez Diaz (IIS/FJD), 28015 Madrid, Spain; (N.H.); (J.O.); (A.R.S.); (D.S.M.)
| | - Alessandra Dimino
- Department of Surgical, Oncological and Oral Sciences, Section of Medical Oncology, University of Palermo, 90127 Palermo, Italy;
| | - Javier Martín-Broto
- Instituto de Investigacion Sanitaria Fundacion Jimenez Diaz (IIS/FJD), 28015 Madrid, Spain; (N.H.); (J.O.); (A.R.S.); (D.S.M.)
- Medical Oncology Department, Fundación Jimenez Diaz University Hospital, 28040 Madrid, Spain
- General de Villalba University Hospital, 28400 Madrid, Spain
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5
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Kontbay T, Şıklar Z, Ceylaner S, Berberoğlu M. Central Precocious Puberty in an Infant with Sotos Syndrome and Response to Treatment. J Clin Res Pediatr Endocrinol 2022; 14:356-360. [PMID: 34013836 PMCID: PMC9422921 DOI: 10.4274/jcrpe.galenos.2021.2020.0273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 05/07/2021] [Indexed: 12/05/2022] Open
Abstract
Sotos syndrome (SS) is characterized by overgrowth, distinctive facial appearance, and learning disability. It is caused by heterozygous mutations, including deletions of NSD1 located at chromosome 5q35. While advanced bone age can occur in some cases, precocious puberty (PP) has only been reported in three cases previously. Here, we reported a case of SS diagnosed in the infancy period with central PP. The discovery of potential factors that trigger puberty is one of the central mysteries of pubertal biology. Depot gonadotropin-releasing hormone analogs constitute the first-line therapy in central PP (CPP), which has proven to be both effective and safe. In our cases, leuprolide acetate at maximum dose was not successful in controlling pubertal progression, and cyproterone acetate (CPA) was added to therapy, with successful control of pubertal progression. In some specific syndromes with PP, such as SS, treatment can be challenging. CPA may be an asset for effective treatment.
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Affiliation(s)
- Tuğba Kontbay
- Şanlıurfa Training and Research Hospital, Clinic of Pediatric Endocrinology, Şanlıurfa, Turkey
| | - Zeynep Şıklar
- Ankara University Faculty of Medicine, Department of Pediatric Endocrinology, Ankara, Turkey
| | | | - Merih Berberoğlu
- Ankara University Faculty of Medicine, Department of Pediatric Endocrinology, Ankara, Turkey
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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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7
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Schmidt VF, Wieland I, Wohlgemuth WA, Ricke J, Wildgruber M, Zenker M. Mosaic RASopathy due to KRAS variant G12D with segmental overgrowth and associated peripheral vascular malformations. Am J Med Genet A 2021; 185:3122-3128. [PMID: 34114335 DOI: 10.1002/ajmg.a.62386] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 05/11/2021] [Accepted: 05/27/2021] [Indexed: 01/19/2023]
Abstract
Oncogenic RAS variants lead to constitutive overactivation and increased signal transduction into downstream pathways. They are found as somatic driver events in various types of human cancer. In a somatic mosaic status, the same RAS variants have been associated with a wide spectrum of focal or segmental tissue dysplasia and overgrowth including various types of congenital nevi, vascular malformations, and other changes (mosaic RASopathies). We present a 3-year-old male patient with segmental overgrowth of the subcutaneous fatty tissue of the right lower extremity with colocalized arteriovenous and capillary malformations and dysplastic draining veins in combination with talipes equinovarus of the right foot. In tissue biopsies of the affected extremity, we identified a mosaic KRAS variant, c.35G>A (p.Gly12Asp), while this variant was absent in the DNA extracted from a biopsy of the normal extremity. This report provides further evidence for the wide clinical and phenotypic variability associated with mosaic KRAS variants. The described pattern confirms that the combination of segmental overgrowth and vascular anomalies in the form of arteriovenous and capillary malformations is a possible manifestation of a mosaic RASopathy. The accurate genetic diagnosis is crucial for molecular-targeted therapy, which might be a future therapeutic target for mosaic RASopathies.
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Affiliation(s)
| | - Ilse Wieland
- Institute of Human Genetics, University Hospital Magdeburg, Magdeburg, Germany
| | - Walter A Wohlgemuth
- Department of Radiology, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Jens Ricke
- Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | - Moritz Wildgruber
- Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | - Martin Zenker
- Institute of Human Genetics, University Hospital Magdeburg, Magdeburg, Germany
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Straub J, Gregor A, Sauerer T, Fliedner A, Distel L, Suchy C, Ekici AB, Ferrazzi F, Zweier C. Genetic interaction screen for severe neurodevelopmental disorders reveals a functional link between Ube3a and Mef2 in Drosophila melanogaster. Sci Rep 2020; 10:1204. [PMID: 31988313 PMCID: PMC6985129 DOI: 10.1038/s41598-020-58182-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 01/13/2020] [Indexed: 11/09/2022] Open
Abstract
Neurodevelopmental disorders (NDDs) are clinically and genetically extremely heterogeneous with shared phenotypes often associated with genes from the same networks. Mutations in TCF4, MEF2C, UBE3A, ZEB2 or ATRX cause phenotypically overlapping, syndromic forms of NDDs with severe intellectual disability, epilepsy and microcephaly. To characterize potential functional links between these genes/proteins, we screened for genetic interactions in Drosophila melanogaster. We induced ubiquitous or tissue specific knockdown or overexpression of each single orthologous gene (Da, Mef2, Ube3a, Zfh1, XNP) and in pairwise combinations. Subsequently, we assessed parameters such as lethality, wing and eye morphology, neuromuscular junction morphology, bang sensitivity and climbing behaviour in comparison between single and pairwise dosage manipulations. We found most stringent evidence for genetic interaction between Ube3a and Mef2 as simultaneous dosage manipulation in different tissues including glia, wing and eye resulted in multiple phenotype modifications. We subsequently found evidence for physical interaction between UBE3A and MEF2C also in human cells. Systematic pairwise assessment of the Drosophila orthologues of five genes implicated in clinically overlapping, severe NDDs and subsequent confirmation in a human cell line revealed interactions between UBE3A/Ube3a and MEF2C/Mef2, thus contributing to the characterization of the underlying molecular commonalities.
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Affiliation(s)
- Jonas Straub
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054, Erlangen, Germany
| | - Anne Gregor
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054, Erlangen, Germany
| | - Tatjana Sauerer
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054, Erlangen, Germany
| | - Anna Fliedner
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054, Erlangen, Germany
| | - Laila Distel
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054, Erlangen, Germany
| | - Christine Suchy
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054, Erlangen, Germany
| | - Arif B Ekici
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054, Erlangen, Germany
| | - Fulvia Ferrazzi
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054, Erlangen, Germany
| | - Christiane Zweier
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054, Erlangen, Germany.
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9
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Friedrich RE, Scheuer HT, Kersten JF, Scheuer HA. Supernumerary teeth of permanent dentition in patients with neurofibromatosis type 1. J Craniomaxillofac Surg 2019; 48:98-104. [PMID: 31882234 DOI: 10.1016/j.jcms.2019.12.006] [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: 11/01/2019] [Revised: 11/21/2019] [Accepted: 12/02/2019] [Indexed: 10/25/2022] Open
Abstract
PURPOSE The purpose of the study was the investigation of supernumerary teeth (ST) in the permanent dentition of patients with neurofibromatosis type 1 (NF1). MATERIAL AND METHODS The panoramic radiographs of 200 NF1 patients were analysed for ST. The potential impact of certain neurogenic facial tumours on the measured variable was investigated separately. The results were compared to dental findings in panoramic radiographs of 200 age- and sex-matched controls. RESULTS The total number of ST in all individuals was 23 in 12 patients (3% of total population). However, all ST had developed in the group of NF1 patients (6%), (p = 0.0004). ST were particularly common distal to the molar region. Although ST occur in the region of facial plexiform neurofibroma, the numerical aberrations of the dentition are independent of specific type of facial nerve sheath tumour. CONCLUSION The unusual accumulation of ST in the terminal sections of molar development could be an indicator of preferred points of developmental disorder, in which the genetic predisposition of the patient is involved. Reviewing the results of other NF1 patient collectives is desirable.
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Affiliation(s)
- Reinhard E Friedrich
- Department of Oral and Craniomaxillofacial Surgery, Eppendorf University Hospital, University of Hamburg, Martinist. 52, D-20246, Hamburg, Germany; Neurofibromatosis Laboratory, Hamburg-Lokstedt, Lottest. 55, D-22529, Hamburg, Germany.
| | - Hannah T Scheuer
- Department of Oral and Craniomaxillofacial Surgery, Eppendorf University Hospital, University of Hamburg, Martinist. 52, D-20246, Hamburg, Germany; Neurofibromatosis Laboratory, Hamburg-Lokstedt, Lottest. 55, D-22529, Hamburg, Germany
| | - Jan F Kersten
- Centre for Psychosocial Medicine, Health Services Research in Dermatology and Health Care Research (IVDP), Eppendorf University Hospital, University of Hamburg, Martinist. 52, D-20246, Hamburg, Germany
| | - Hanna A Scheuer
- Orthodontic Practice, Lottest. 55, D-22529, Hamburg, Germany
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10
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Koh AL, Tan ES, Brett MS, Lai AHM, Jamuar SS, Ng I, Tan EC. The spectrum of genetic variants and phenotypic features of Southeast Asian patients with Noonan syndrome. Mol Genet Genomic Med 2019; 7:e00581. [PMID: 30784236 PMCID: PMC6465663 DOI: 10.1002/mgg3.581] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 12/18/2018] [Accepted: 12/31/2018] [Indexed: 12/28/2022] Open
Abstract
Background Noonan syndrome (NS) is an autosomal dominant disorder that belongs to a group of developmental disorders called RASopathies with overlapping features and multiple causative genes. The aim of the study was to identify mutations underlying this disorder in patients from Southeast Asia and characterize their clinical presentations. Methods Patients were identified from the hospital's Genetics clinics after assessment by attending clinical geneticists. A targeted gene panel was used for next‐generation sequencing on genomic DNA extracted from the blood samples of 17 patients. Results Heterozygous missense variants were identified in 13 patients: eight were in PTPN11, three in SOS1, and one each in RIT1 and KRAS. All are known variants that have been reported in patients with NS. Of the 13 patients with identified variants, 10 had short stature, the most common feature for NS. Four of the eight patients with PTPN11 variants had atrial septal defect. Only two had pulmonary stenosis which is reported to be common for PTPN11 mutation carriers. Another two had hypertrophic cardiomyopathy, a feature which is negatively associated with PTPN11 mutations. Conclusions Our study provides the mutation and phenotypic spectrum of NS from a new population group. The molecular testing yield of 76% is similar to other studies and shows that the targeted panel approach is useful for identifying genetic mutations in NS which has multiple causative genes. The molecular basis for the phenotypes of the remaining patients remains unknown and would need to be uncovered via sequencing of additional genes or other investigative methods.
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Affiliation(s)
- Ai-Ling Koh
- Department of Paediatrics, KK Women's & Children's Hospital, Singapore
| | - Ee-Shien Tan
- Genetics Service, Department of Paediatrics, KK Women's & Children's Hospital, Singapore.,Paediatrics Academic Clinical Programme, SingHealth Duke-NUS Graduate Medical School, Singapore
| | - Maggie S Brett
- Research Laboratory, KK Women's & Children's Hospital, Singapore
| | - Angeline H M Lai
- Genetics Service, Department of Paediatrics, KK Women's & Children's Hospital, Singapore.,Paediatrics Academic Clinical Programme, SingHealth Duke-NUS Graduate Medical School, Singapore
| | - Saumya Shekhar Jamuar
- Genetics Service, Department of Paediatrics, KK Women's & Children's Hospital, Singapore.,Paediatrics Academic Clinical Programme, SingHealth Duke-NUS Graduate Medical School, Singapore
| | - Ivy Ng
- Genetics Service, Department of Paediatrics, KK Women's & Children's Hospital, Singapore.,Paediatrics Academic Clinical Programme, SingHealth Duke-NUS Graduate Medical School, Singapore
| | - Ene-Choo Tan
- Genetics Service, Department of Paediatrics, KK Women's & Children's Hospital, Singapore.,Paediatrics Academic Clinical Programme, SingHealth Duke-NUS Graduate Medical School, Singapore.,Research Laboratory, KK Women's & Children's Hospital, Singapore
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11
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Chen L, Zhai L, Al-Kzayer LFY, Sarsam SN, Liu T, Alzakar RH, Nakazawa Y. Neurocutaneous Melanosis in Association With Large Congenital Melanocytic Nevi in Children: A Report of 2 Cases With Clinical, Radiological, and Pathogenetic Evaluation. Front Neurol 2019; 10:79. [PMID: 30792691 PMCID: PMC6374324 DOI: 10.3389/fneur.2019.00079] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/21/2019] [Indexed: 11/28/2022] Open
Abstract
Background: Melanocytic nevi present at birth, or within the first few months of life, are defined as congenital melanocytic nevi (CMN). Neurocutaneous melanosis (NCM) is a rare disorder, represents pigment cell tumors of the leptomeninges, and occurs in association with large or multiple CMN. NCM carries an extremely poor prognosis. NRAS and BRAFV600E genetic mutations were reported in CMN. Our aim was to report 2 rare cases of NCM associated with large-sized CMN. Materials and Methods: Two cases were enrolled, a 19-month-old boy with multiple satellite and giant CMN (GCMN); and a 57-month-old girl with large CMN (LCMN). Both patients had central nervous system (CNS) symptoms, and therefore, were studied from clinical, radiological, and immunohistopathological aspects. Cytogenetic study was done for one of them. Results: Both patients had CMN located in the head/neck, with no cutaneous melanoma. MRI was the most reliable method for early detection of NCM. NCM was proved in the 2 studied cases by immunohistopathology performed after surgery. The boy with GCMN carried NRAS mutation at codon 61, in addition to the characteristic facial features relevant to RASopathies. Both patients died despite surgical intervention. Conclusion: Our report highlights the need for pediatricians to be alert to the risk of NCM in association with CMN, especially when a CMN lesion is large, or there are multiple satellite lesions, or the nevus location is at the head or neck. Moreover, in the setting of CMN, the absence of skin melanoma does not exclude the presence of NCM.
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Affiliation(s)
- Lei Chen
- Department of Pathology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Liqin Zhai
- Department of Pathology, Shanxi Provincial People's Hospital, Taiyuan, China
| | | | | | - Tingting Liu
- Department of Pediatric Hematology/Oncology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Riyadh H Alzakar
- Department of Dermatology, Al-Hamdaniya General Hospital, Mosul, Iraq
| | - Yozo Nakazawa
- Department of Pediatrics, Shinshu University School of Medicine, Matsumoto, Japan
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12
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Abstract
The MAPK pathway is a prominent intracellular signaling pathway regulating various intracellular functions. Components of this pathway are mutated in a related collection of congenital syndromes collectively referred to as neuro-cardio-facio-cutaneous syndromes (NCFC) or Rasopathies. Recently, it has been appreciated that these disorders are associated with autism spectrum disorders (ASD). In addition, idiopathic ASD has also implicated the MAPK signaling cascade as a common pathway that is affected by many of the genetic variants that have been found to be linked to ASDs. This chapter describes the components of the MAPK pathway and how it is regulated. Furthermore, this chapter will highlight the various functions of the MAPK pathway during both embryonic development of the central nervous system (CNS) and its roles in neuronal physiology and ultimately, behavior. Finally, we will summarize the perturbations to MAPK signaling in various models of autism spectrum disorders and Rasopathies to highlight how dysregulation of this pivotal pathway may contribute to the pathogenesis of autism.
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13
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Jung NH, Münchau A, Mall V. [Neuronal plasticity and neuromodulation in pediatric neurology]. DER NERVENARZT 2018; 89:1131-1139. [PMID: 30141068 DOI: 10.1007/s00115-018-0586-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
BACKGROUND Neuronal plasticity is a core mechanism for learning and memory. Abnormal neuronal plasticity has emerged as a key mechanism in many neurological and neuropediatric diseases. OBJECTIVE Chances and perspectives of neuromodulation techniques in neurological and neuropediatric diseases with altered neuronal plasticity. MATERIAL AND METHODS Presentation and discussion of own results of neuronal plasticity investigations in patients with neurodevelopmental disorders including RASopathies, autism spectrum disorders (ASD) and Gilles de la Tourette syndrome (GTS). RESULTS The results of neuronal plasticity studies in patients with RASopathies, ASD and GTS underline the pathophysiological relevance of abnormal neuronal plasticity in these diseases. Transcranial magnetic stimulation (TMS) is a useful tool to examine and also induce neuronal plasticity in these patients. CONCLUSION Neuronal plasticity appears to be an important pathophysiological factor in neuronal developmental disorders and can be investigated using TMS. New and innovative techniques may offer novel approaches for individualized TMS applications, particularly in children with neuropediatric conditions.
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Affiliation(s)
- N H Jung
- Fakultät für Medizin, Lehrstuhl für Sozialpädiatrie, Technische Universität München, Heiglhoftstr. 65, 81377, München, Deutschland.
| | - A Münchau
- Institut für Neurogenetik, Universität zu Lübeck, Marie-Curie-Straße, 23562, Lübeck, Deutschland
| | - V Mall
- Fakultät für Medizin, Lehrstuhl für Sozialpädiatrie, Technische Universität München, Heiglhoftstr. 65, 81377, München, Deutschland
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14
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Gelb BD, Cavé H, Dillon MW, Gripp KW, Lee JA, Mason-Suares H, Rauen KA, Williams B, Zenker M, Vincent LM. ClinGen's RASopathy Expert Panel consensus methods for variant interpretation. Genet Med 2018; 20:1334-1345. [PMID: 29493581 PMCID: PMC6119537 DOI: 10.1038/gim.2018.3] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 01/02/2018] [Indexed: 01/06/2023] Open
Abstract
Purpose Standardized and accurate variant assessment is essential for effective medical care. To that end, Clinical Genome (ClinGen) Resource clinical domain working groups (CDWG) are systematically reviewing disease-associated genes for sufficient evidence to support disease causality and creating disease-specific specifications of ACMG-AMP guidelines for consistent and accurate variant classification. Methods The ClinGen RASopathy CDWG established an expert panel (EP) to curate gene information and generate gene and disease-specific specifications to ACMG-AMP variant classification framework. These specifications were tested by classifying 37 exemplar pathogenic variants plus an additional 66 variants in ClinVar distributed across nine RASopathy genes. Results RASopathy-related specifications were applied to sixteen ACMG-AMP criteria, with five also having adjustable strength with availability of additional evidence. Another five criteria were deemed not applicable. Key adjustments to minor allele frequency thresholds, multiple de novo occurrence events and/or segregation, and strength adjustments impacted 60% of variant classifications. Unpublished case-level data from participating laboratories impacted 45% of classifications supporting the need for data sharing. Conclusions RAS-specific ACMG-AMP specifications optimized the utility of available clinical evidence and Ras/MAPK pathway-specific characteristics to consistently classify RASopathy-associated variants. These specifications highlight how grouping genes by shared features promotes rapid multi-genic variant assessment without sacrificing specificity and accuracy.
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Affiliation(s)
- Bruce D Gelb
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Hélène Cavé
- Département de Génétique, Hôpital Robert Debré and Institut Universitaire d'Hématologie, Université Paris Diderot, Paris-Sorbonne-Cité, Paris, France
| | - Mitchell W Dillon
- Icahn School of Medicine at Mount Sinai, Molecular Genetic Testing Laboratory, New York, New York, USA
| | - Karen W Gripp
- Division of Medical Genetics, A.I. duPont Hospital for Children, Wilmington, Delaware, USA
| | - Jennifer A Lee
- Greenwood Genetic Center, Greenwood, South Carolina, USA
| | - Heather Mason-Suares
- Laboratory for Molecular Medicine, Partners Healthcare, Cambridge, Massachusetts, USA
| | - Katherine A Rauen
- Department of Pediatrics, University of California Davis, UC Davis MIND Institute, Sacramento, California, USA
| | | | - Martin Zenker
- Institute of Human Genetics, University Hospital Magdeburg, Magdeburg, Germany
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15
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Genotype and phenotype spectrum of NRAS germline variants. Eur J Hum Genet 2017; 25:823-831. [PMID: 28594414 DOI: 10.1038/ejhg.2017.65] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 03/14/2017] [Accepted: 03/28/2017] [Indexed: 12/20/2022] Open
Abstract
RASopathies comprise a group of disorders clinically characterized by short stature, heart defects, facial dysmorphism, and varying degrees of intellectual disability and cancer predisposition. They are caused by germline variants in genes encoding key components or modulators of the highly conserved RAS-MAPK signalling pathway that lead to dysregulation of cell signal transmission. Germline changes in the genes encoding members of the RAS subfamily of GTPases are rare and associated with variable phenotypes of the RASopathy spectrum, ranging from Costello syndrome (HRAS variants) to Noonan and Cardiofaciocutaneous syndromes (KRAS variants). A small number of RASopathy cases with disease-causing germline NRAS alterations have been reported. Affected individuals exhibited features fitting Noonan syndrome, and the observed germline variants differed from the typical oncogenic NRAS changes occurring as somatic events in tumours. Here we describe 19 new cases with RASopathy due to disease-causing variants in NRAS. Importantly, four of them harbored missense changes affecting Gly12, which was previously described to occur exclusively in cancer. The phenotype in our cohort was variable but well within the RASopathy spectrum. Further, one of the patients (c.35G>A; p.(Gly12Asp)) had a myeloproliferative disorder, and one subject (c.34G>C; p.(Gly12Arg)) exhibited an uncharacterized brain tumour. With this report, we expand the genotype and phenotype spectrum of RASopathy-associated germline NRAS variants and provide evidence that NRAS variants do not spare the cancer-associated mutation hotspots.
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16
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Aberrant neuronal activity-induced signaling and gene expression in a mouse model of RASopathy. PLoS Genet 2017; 13:e1006684. [PMID: 28346493 PMCID: PMC5386306 DOI: 10.1371/journal.pgen.1006684] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 04/10/2017] [Accepted: 03/13/2017] [Indexed: 12/16/2022] Open
Abstract
Noonan syndrome (NS) is characterized by reduced growth, craniofacial abnormalities, congenital heart defects, and variable cognitive deficits. NS belongs to the RASopathies, genetic conditions linked to mutations in components and regulators of the Ras signaling pathway. Approximately 50% of NS cases are caused by mutations in PTPN11. However, the molecular mechanisms underlying cognitive impairments in NS patients are still poorly understood. Here, we report the generation and characterization of a new conditional mouse strain that expresses the overactive Ptpn11D61Y allele only in the forebrain. Unlike mice with a global expression of this mutation, this strain is viable and without severe systemic phenotype, but shows lower exploratory activity and reduced memory specificity, which is in line with a causal role of disturbed neuronal Ptpn11 signaling in the development of NS-linked cognitive deficits. To explore the underlying mechanisms we investigated the neuronal activity-regulated Ras signaling in brains and neuronal cultures derived from this model. We observed an altered surface expression and trafficking of synaptic glutamate receptors, which are crucial for hippocampal neuronal plasticity. Furthermore, we show that the neuronal activity-induced ERK signaling, as well as the consecutive regulation of gene expression are strongly perturbed. Microarray-based hippocampal gene expression profiling revealed profound differences in the basal state and upon stimulation of neuronal activity. The neuronal activity-dependent gene regulation was strongly attenuated in Ptpn11D61Y neurons. In silico analysis of functional networks revealed changes in the cellular signaling beyond the dysregulation of Ras/MAPK signaling that is nearly exclusively discussed in the context of NS at present. Importantly, changes in PI3K/AKT/mTOR and JAK/STAT signaling were experimentally confirmed. In summary, this study uncovers aberrant neuronal activity-induced signaling and regulation of gene expression in Ptpn11D61Y mice and suggests that these deficits contribute to the pathophysiology of cognitive impairments in NS.
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17
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Couto JA, Huang AY, Konczyk DJ, Goss JA, Fishman SJ, Mulliken JB, Warman ML, Greene AK. Somatic MAP2K1 Mutations Are Associated with Extracranial Arteriovenous Malformation. Am J Hum Genet 2017; 100:546-554. [PMID: 28190454 DOI: 10.1016/j.ajhg.2017.01.018] [Citation(s) in RCA: 173] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 01/06/2017] [Indexed: 01/09/2023] Open
Abstract
Arteriovenous malformation (AVM) is a fast-flow, congenital vascular anomaly that may arise anywhere in the body. AVMs typically progress, causing destruction of surrounding tissue and, sometimes, cardiac overload. AVMs are difficult to control; they often re-expand after embolization or resection, and pharmacologic therapy is unavailable. We studied extracranial AVMs in order to identify their biological basis. We performed whole-exome sequencing (WES) and whole-genome sequencing (WGS) on AVM tissue from affected individuals. Endothelial cells were separated from non-endothelial cells by immune-affinity purification. We used droplet digital PCR (ddPCR) to confirm mutations found by WES and WGS, to determine whether mutant alleles were enriched in endothelial or non-endothelial cells, and to screen additional AVM specimens. In seven of ten specimens, WES and WGS detected and ddPCR confirmed somatic mutations in mitogen activated protein kinase kinase 1 (MAP2K1), the gene that encodes MAP-extracellular signal-regulated kinase 1 (MEK1). Mutant alleles were enriched in endothelial cells and were not present in blood or saliva. 9 of 15 additional AVM specimens contained mutant MAP2K1 alleles. Mutations were missense or small in-frame deletions that affect amino acid residues within or adjacent to the protein's negative regulatory domain. Several of these mutations have been found in cancers and shown to increase MEK1 activity. In summary, somatic mutations in MAP2K1 are a common cause of extracranial AVM. The likely mechanism is endothelial cell dysfunction due to increased MEK1 activity. MEK1 inhibitors, which are approved to treat several forms of cancer, are potential therapeutic agents for individuals with extracranial AVM.
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18
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van der Kaay DCM, Levine BS, Doyle D, Mendoza-Londono R, Palmert MR. RASopathies Are Associated With Delayed Puberty; Are They Associated With Precocious Puberty Too? Pediatrics 2016; 138:peds.2016-0182. [PMID: 27940666 DOI: 10.1542/peds.2016-0182] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/09/2016] [Indexed: 11/24/2022] Open
Abstract
RASopathies, such as Noonan, Costello, and cardio-facio-cutaneous syndromes, are developmental disorders caused by mutations in rat sarcoma-mitogen-activated protein kinase pathway genes. Mutations that cause Noonan syndrome have been associated with delayed puberty. Here we report 4 patients with either Costello or cardio-facio-cutaneous syndrome who developed precocious puberty, suggesting complex regulation of the hypothalamic-pituitary-gonadal axis and the timing of puberty by the rat sarcoma-mitogen-activated protein kinase pathway. Additional study of the timing of puberty among patients with RASopathies is warranted to ascertain the incidence of delayed and precocious puberty in these conditions and to examine genotype-phenotype correlations, which may provide insight into pathways that regulate the timing of puberty.
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Affiliation(s)
| | - Bat-Sheva Levine
- Division of Endocrinology, Boston Children's Hospital, Boston, Massachusetts; and
| | - Daniel Doyle
- Division of Endocrinology, Nemours Alfred I. Dupont Hospital for Children, Wilmington, Delaware
| | - Roberto Mendoza-Londono
- Divisions of Endocrinology and.,Clinical and Metabolic Genetics, The Hospital for Sick Children, and
| | - Mark R Palmert
- Divisions of Endocrinology and.,Departments of Pediatrics and.,Physiology, The University of Toronto, Toronto, Ontario, Canada
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19
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Ryu HH, Lee YS. Cell type-specific roles of RAS-MAPK signaling in learning and memory: Implications in neurodevelopmental disorders. Neurobiol Learn Mem 2016; 135:13-21. [PMID: 27296701 DOI: 10.1016/j.nlm.2016.06.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 05/28/2016] [Accepted: 06/09/2016] [Indexed: 01/17/2023]
Abstract
The RAS-mitogen-activated protein kinase (MAPK) signaling pathway plays critical roles in brain function, including learning and memory. Mutations of molecules in the RAS-MAPK pathway are associated with a group of disorders called RASopathies, which include Noonan syndrome, neurofibromatosis type 1, Costello syndrome, Noonan syndrome with multiple lentigines, Legius syndrome, and cardio-facio-cutaneous syndrome. RASopathies share certain clinical symptoms, including craniofacial abnormalities, heart defects, delayed growth, and cognitive deficits such as learning disabilities, while each individual syndrome also displays unique phenotypes. Recent studies using mouse models of RASopathies showed that each disorder may have a distinct molecular and cellular etiology depending on the cellular specificity of the mutated molecules. Here, we review the cell-type specific roles of the regulators of the RAS-MAPK pathway in cognitive function (learning and memory) and their contribution to the development of RASopathies. We also discussed recent technical advances in analyzing cell type-specific transcriptomes and proteomes in the nervous system. Understanding specific mechanisms for these similar but distinct disorders would facilitate the development of mechanism-based individualized treatment for RASopathies.
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Affiliation(s)
- Hyun-Hee Ryu
- Department of Life Science, College of Natural Science, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, South Korea; Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Yong-Seok Lee
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Republic of Korea.
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20
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Boppudi S, Bögershausen N, Hove H, Percin E, Aslan D, Dvorsky R, Kayhan G, Li Y, Cursiefen C, Tantcheva-Poor I, Toft P, Bartsch O, Lissewski C, Wieland I, Jakubiczka S, Wollnik B, Ahmadian M, Heindl L, Zenker M. Specific mosaicKRASmutations affecting codon 146 cause oculoectodermal syndrome and encephalocraniocutaneous lipomatosis. Clin Genet 2016; 90:334-42. [DOI: 10.1111/cge.12775] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 02/29/2016] [Accepted: 03/06/2016] [Indexed: 01/08/2023]
Affiliation(s)
- S. Boppudi
- Institute of Human Genetics; University Hospital Magdeburg, Otto-von-Guericke University; Magdeburg Germany
| | - N. Bögershausen
- Institute of Human Genetics; University Medical Center Goettingen, Georg-August University; Goettingen Germany
- Institute of Human Genetics; University of Cologne; Cologne Germany
| | - H.B. Hove
- Department of Clinical Genetics; Copenhagen University Hospital Rigshospitalet; Copenhagen Denmark
| | - E.F. Percin
- Department of Medical Genetics, Faculty of Medicine; Gazi University; Ankara Turkey
| | - D. Aslan
- Section of Hematology, Department of Pediatrics, Faculty of Medicine; Gazi University; Ankara Turkey
| | - R. Dvorsky
- Institute of Biochemistry and Molecular Biology II, Medical Faculty; Heinrich-Heine-University; Düsseldorf Germany
| | - G. Kayhan
- Department of Medical Genetics, Faculty of Medicine; Gazi University; Ankara Turkey
| | - Y. Li
- Institute of Human Genetics; University Medical Center Goettingen, Georg-August University; Goettingen Germany
- Institute of Human Genetics; University of Cologne; Cologne Germany
| | - C. Cursiefen
- Department of Ophthalmology; University of Cologne; Cologne Germany
| | | | - P.B. Toft
- Department of Ophthalmology; Copenhagen University Hospital Rigshospitalet; Copenhagen Denmark
| | - O. Bartsch
- Institute of Human Genetics; University Medical Centre of the Johannes Gutenberg University Mainz; Mainz Germany
| | - C. Lissewski
- Institute of Human Genetics; University Hospital Magdeburg, Otto-von-Guericke University; Magdeburg Germany
| | - I. Wieland
- Institute of Human Genetics; University Hospital Magdeburg, Otto-von-Guericke University; Magdeburg Germany
| | - S. Jakubiczka
- Institute of Human Genetics; University Hospital Magdeburg, Otto-von-Guericke University; Magdeburg Germany
| | - B. Wollnik
- Institute of Human Genetics; University Medical Center Goettingen, Georg-August University; Goettingen Germany
- Institute of Human Genetics; University of Cologne; Cologne Germany
| | - M.R. Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty; Heinrich-Heine-University; Düsseldorf Germany
| | - L.M. Heindl
- Department of Ophthalmology; University of Cologne; Cologne Germany
| | - M. Zenker
- Institute of Human Genetics; University Hospital Magdeburg, Otto-von-Guericke University; Magdeburg Germany
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21
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Zenker M, Kutsche K. RASopathien. MED GENET-BERLIN 2016. [DOI: 10.1007/s11825-016-0080-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Zusammenfassung
Die RASopathien umfassen das Noonan-Syndrom, seltenere verwandte Syndrome (CFC-, Costello und LEOPARD-Syndrom) sowie die Neurofibromatose Typ 1 und ähnliche Erkrankungen (Legius-, NF1-Noonan-Syndrom). Die allen RASopathien zugrunde liegenden genetischen Veränderungen bedingen eine konstitutionelle Fehlregulation des RAS-MAPK-Signalwegs. Es resultiert ein typisches Muster an angeborenen Anomalien und Entwicklungsstörungen in variabler Ausprägung. Typische klinische Merkmale sind kardiale Anomalien, vermindertes Wachstum, kraniofaziale Dysmorphien und Entwicklungsverzögerung. Die Tumordisposition hängt von der jeweiligen Erkrankung und genetischen Veränderung ab. Die molekularen Erkenntnisse machen klinische Überschneidungen und Unterschiede zwischen den Entitäten verständlich. Die genetische Diagnostik ist breit verfügbar. Die Behandlung der Patienten ist bislang nur symptomatisch und erfordert ein interdisziplinäres Management und lebenslange Betreuung der Patienten.
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Affiliation(s)
- Martin Zenker
- Aff1 grid.411559.d 0000000095924695 Institut für Humangenetik Universitätsklinikum Magdeburg Leipziger Str. 44 39120 Magdeburg Deutschland
| | - Kerstin Kutsche
- Aff2 grid.13648.38 0000000121803484 Institut für Humangenetik Universitätsklinikum Hamburg-Eppendorf Hamburg Deutschland
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22
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Krencik R, Hokanson KC, Narayan AR, Dvornik J, Rooney GE, Rauen KA, Weiss LA, Rowitch DH, Ullian EM. Dysregulation of astrocyte extracellular signaling in Costello syndrome. Sci Transl Med 2016; 7:286ra66. [PMID: 25947161 DOI: 10.1126/scitranslmed.aaa5645] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Astrocytes produce an assortment of signals that promote neuronal maturation according to a precise developmental timeline. Is this orchestrated timing and signaling altered in human neurodevelopmental disorders? To address this question, the astroglial lineage was investigated in two model systems of a developmental disorder with intellectual disability caused by mutant Harvey rat sarcoma viral oncogene homolog (HRAS) termed Costello syndrome: mutant HRAS human induced pluripotent stem cells (iPSCs) and transgenic mice. Human iPSCs derived from patients with Costello syndrome differentiated to astroglia more rapidly in vitro than those derived from wild-type cell lines with normal HRAS, exhibited hyperplasia, and also generated an abundance of extracellular matrix remodeling factors and proteoglycans. Acute treatment with a farnesyl transferase inhibitor and knockdown of the transcription factor SNAI2 reduced expression of several proteoglycans in Costello syndrome iPSC-derived astrocytes. Similarly, mice in which mutant HRAS was expressed selectively in astrocytes exhibited experience-independent increased accumulation of perineuronal net proteoglycans in cortex, as well as increased parvalbumin expression in interneurons, when compared to wild-type mice. Our data indicate that astrocytes expressing mutant HRAS dysregulate cortical maturation during development as shown by abnormal extracellular matrix remodeling and implicate excessive astrocyte-to-neuron signaling as a possible drug target for treating mental impairment and enhancing neuroplasticity.
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Affiliation(s)
- Robert Krencik
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Kenton C Hokanson
- Neuroscience Program, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Aditi R Narayan
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jill Dvornik
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Gemma E Rooney
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Katherine A Rauen
- Department of Pediatrics, University of California, Davis, Sacramento, CA 95817, USA
| | - Lauren A Weiss
- Department of Psychiatry and Institute for Human Genetics, University of California, San Francisco, San Francisco, CA 94143, USA
| | - David H Rowitch
- Department of Pediatrics, Eli and Edythe Broad Institute for Regenerative Medicine and Stem Cell Research, and Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Erik M Ullian
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA 94143, USA. Department of Physiology, University of California, San Francisco, San Francisco, CA 94143, USA.
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23
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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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24
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Kochinke K, Zweier C, Nijhof B, Fenckova M, Cizek P, Honti F, Keerthikumar S, Oortveld M, Kleefstra T, Kramer J, Webber C, Huynen M, Schenck A. Systematic Phenomics Analysis Deconvolutes Genes Mutated in Intellectual Disability into Biologically Coherent Modules. Am J Hum Genet 2016; 98:149-64. [PMID: 26748517 DOI: 10.1016/j.ajhg.2015.11.024] [Citation(s) in RCA: 202] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 11/25/2015] [Indexed: 10/22/2022] Open
Abstract
Intellectual disability (ID) disorders are genetically and phenotypically extremely heterogeneous. Can this complexity be depicted in a comprehensive way as a means of facilitating the understanding of ID disorders and their underlying biology? We provide a curated database of 746 currently known genes, mutations in which cause ID (ID-associated genes [ID-AGs]), classified according to ID manifestation and associated clinical features. Using this integrated resource, we show that ID-AGs are substantially enriched with co-expression, protein-protein interactions, and specific biological functions. Systematic identification of highly enriched functional themes and phenotypes revealed typical phenotype combinations characterizing process-defined groups of ID disorders, such as chromatin-related disorders and deficiencies in DNA repair. Strikingly, phenotype classification efficiently breaks down ID-AGs into subsets with significantly elevated biological coherence and predictive power. Custom-made functional Drosophila datasets revealed further characteristic phenotypes among ID-AGs and specific clinical classes. Our study and resource provide systematic insights into the molecular and clinical landscape of ID disorders, represent a significant step toward overcoming current limitations in ID research, and prove the utility of systematic human and cross-species phenomics analyses in highly heterogeneous genetic disorders.
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25
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Dentate Gyrus Development Requires ERK Activity to Maintain Progenitor Population and MAPK Pathway Feedback Regulation. J Neurosci 2015; 35:6836-48. [PMID: 25926459 DOI: 10.1523/jneurosci.4196-14.2015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The ERK/MAPK pathway is an important developmental signaling pathway. Mutations in upstream elements of this pathway result in neuro-cardio-facial cutaneous (NCFC) syndromes, which are typified by impaired neurocognitive abilities that are reliant upon hippocampal function. The role of ERK signaling during hippocampal development has not been examined and may provide critical insight into the cause of hippocampal dysfunction in NCFC syndromes. In this study, we have generated ERK1 and conditional ERK2 compound knock-out mice to determine the role of ERK signaling during development of the hippocampal dentate gyrus. We found that loss of both ERK1 and ERK2 resulted in 60% fewer granule cells and near complete absence of neural progenitor pools in the postnatal dentate gyrus. Loss of ERK1/2 impaired maintenance of neural progenitors as they migrate from the dentate ventricular zone to the dentate gyrus proper, resulting in premature depletion of neural progenitor cells beginning at E16.5, which prevented generation of granule cells later in development. Finally, loss of ERK2 alone does not impair development of the dentate gyrus as animals expressing only ERK1 developed a normal hippocampus. These findings establish that ERK signaling regulates maintenance of progenitor cells required for development of the dentate gyrus.
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26
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Schulze-Bahr E, Klaassen S, Abdul-Khaliq H, Schunkert H. Gendiagnostik bei kardiovaskulären Erkrankungen. KARDIOLOGE 2015. [DOI: 10.1007/s12181-014-0636-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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27
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Southgate L, Sukalo M, Karountzos ASV, Taylor EJ, Collinson CS, Ruddy D, Snape KM, Dallapiccola B, Tolmie JL, Joss S, Brancati F, Digilio MC, Graul-Neumann LM, Salviati L, Coerdt W, Jacquemin E, Wuyts W, Zenker M, Machado RD, Trembath RC. Haploinsufficiency of the NOTCH1 Receptor as a Cause of Adams-Oliver Syndrome With Variable Cardiac Anomalies. ACTA ACUST UNITED AC 2015; 8:572-581. [PMID: 25963545 DOI: 10.1161/circgenetics.115.001086] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 05/01/2015] [Indexed: 01/17/2023]
Abstract
BACKGROUND Adams-Oliver syndrome (AOS) is a rare disorder characterized by congenital limb defects and scalp cutis aplasia. In a proportion of cases, notable cardiac involvement is also apparent. Despite recent advances in the understanding of the genetic basis of AOS, for the majority of affected subjects, the underlying molecular defect remains unresolved. This study aimed to identify novel genetic determinants of AOS. METHODS AND RESULTS Whole-exome sequencing was performed for 12 probands, each with a clinical diagnosis of AOS. Analyses led to the identification of novel heterozygous truncating NOTCH1 mutations (c.1649dupA and c.6049_6050delTC) in 2 kindreds in which AOS was segregating as an autosomal dominant trait. Screening a cohort of 52 unrelated AOS subjects, we detected 8 additional unique NOTCH1 mutations, including 3 de novo amino acid substitutions, all within the ligand-binding domain. Congenital heart anomalies were noted in 47% (8/17) of NOTCH1-positive probands and affected family members. In leukocyte-derived RNA from subjects harboring NOTCH1 extracellular domain mutations, we observed significant reduction of NOTCH1 expression, suggesting instability and degradation of mutant mRNA transcripts by the cellular machinery. Transient transfection of mutagenized NOTCH1 missense constructs also revealed significant reduction in gene expression. Mutant NOTCH1 expression was associated with downregulation of the Notch target genes HEY1 and HES1, indicating that NOTCH1-related AOS arises through dysregulation of the Notch signaling pathway. CONCLUSIONS These findings highlight a key role for NOTCH1 across a range of developmental anomalies that include cardiac defects and implicate NOTCH1 haploinsufficiency as a likely molecular mechanism for this group of disorders.
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Affiliation(s)
- Laura Southgate
- Division of Genetics & Molecular Medicine, King's College London, Faculty of Life Sciences & Medicine, Guy's Hospital, London, United Kingdom.,Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London, United Kingdom
| | - Maja Sukalo
- Institute of Human Genetics, Otto-von-Guericke-Universität Magdeburg, University Hospital Magdeburg, Magdeburg, Germany
| | | | - Edward J Taylor
- School of Life Sciences, University of Lincoln, Lincoln, United Kingdom
| | - Claire S Collinson
- Division of Genetics & Molecular Medicine, King's College London, Faculty of Life Sciences & Medicine, Guy's Hospital, London, United Kingdom
| | - Deborah Ruddy
- Department of Clinical Genetics, Guy's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Katie M Snape
- Department of Clinical Genetics, South West Thames Regional Genetics Service, St George's Healthcare NHS Trust, London, United Kingdom
| | - Bruno Dallapiccola
- Scientific Directorate, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - John L Tolmie
- South West of Scotland Clinical Genetics Service, Southern General Hospital, Glasgow, United Kingdom
| | - Shelagh Joss
- South West of Scotland Clinical Genetics Service, Southern General Hospital, Glasgow, United Kingdom
| | - Francesco Brancati
- Department of Medical, Oral & Biotechnological Sciences, Gabriele d'Annunzio University of Chieti-Pescara, Chieti, Italy
| | | | | | - Leonardo Salviati
- Clinical Genetics Unit, Department of Woman & Child Health, University of Padova, Padova, Italy
| | - Wiltrud Coerdt
- Institute of Human Genetics, Mainz University Medical Center, Mainz, Germany
| | - Emmanuel Jacquemin
- Pediatric Hepatology & Liver Transplantation Unit, Bicêtre Hospital, Assistance Publique - Hôpitaux de Paris, Hepatinov, Le Kremlin Bicêtre, France.,Inserm U1174, University Paris-Sud 11, Orsay, France
| | - Wim Wuyts
- Department of Medical Genetics, University & University Hospital of Antwerp, Edegem, Belgium
| | - Martin Zenker
- Institute of Human Genetics, Otto-von-Guericke-Universität Magdeburg, University Hospital Magdeburg, Magdeburg, Germany
| | - Rajiv D Machado
- School of Life Sciences, University of Lincoln, Lincoln, United Kingdom
| | - Richard C Trembath
- Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London, United Kingdom.,Department of Clinical Genetics, Guy's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
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Sheffield BS, Yip S, Ruchelli ED, Dunham CP, Sherwin E, Brooks PA, Sur A, Singh A, Human DG, Patel MS, Lee AF. Fatal congenital hypertrophic cardiomyopathy and a pancreatic nodule morphologically identical to focal lesion of congenital hyperinsulinism in an infant with costello syndrome: case report and review of the literature. Pediatr Dev Pathol 2015; 18:237-44. [PMID: 25668678 DOI: 10.2350/14-07-1525-cr.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Costello syndrome is characterized by constitutional mutations in the proto-oncogene HRAS, causing dysmorphic features, multiple cardiac problems, intellectual disability, and an increased risk of neoplasia. We report a male infant with dysmorphic features, born prematurely at 32 weeks, who, during his 3-month life span, had an unusually severe and ultimately fatal manifestation of hypertrophic cardiomyopathy and hyperinsulinemic hypoglycemia. Molecular studies in this patient demonstrated the uncommon Q22K mutation in the HRAS gene, diagnostic of Costello syndrome. The major autopsy findings revealed hypertrophic cardiomyopathy, congenital myopathy, and a 1.4-cm pancreatic nodule that was positive for insulin expression and morphologically identical to a focal lesion of congenital hyperinsulinism. Sequencing of KCNJ11 and ABCC8, the 2 most commonly mutated genes in focal lesion of congenital hyperinsulinism, revealed no mutations. While hyperinsulinism is a recognized feature of RASopathies, a focal proliferation of endocrine cells similar to a focal lesion of hyperinsulinism is a novel pathologic finding in Costello syndrome.
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Affiliation(s)
- Brandon S. Sheffield
- Faculty of Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC, Canada
- Division of Anatomical Pathology, Children's and Women's Health Centre of British Columbia, and Department of Pathology and Laboratory Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC V6H3V4, Canada
| | - Stephen Yip
- Faculty of Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC, Canada
- Centre for Translational and Applied Genomics, British Columbia Cancer Agency, 600 West 10th Avenue, Vancouver, BC V6H3V4, Canada
| | - Eduardo D. Ruchelli
- Division of Anatomical Pathology, The Children's Hospital of Philadelphia. 34th Street and Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Christopher P. Dunham
- Faculty of Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC, Canada
- Division of Anatomical Pathology, Children's and Women's Health Centre of British Columbia, and Department of Pathology and Laboratory Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC V6H3V4, Canada
| | - Elizabeth Sherwin
- Faculty of Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC, Canada
- Division of Pediatric Cardiology, Children's and Women's Health Centre of British Columbia, 4480 Oak Street, Room 1C50, Vancouver, BC V6H3V4, Canada
| | - Paul A. Brooks
- Faculty of Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC, Canada
- Division of Pediatric Cardiology, Children's and Women's Health Centre of British Columbia, 4480 Oak Street, Room 1C50, Vancouver, BC V6H3V4, Canada
| | - Amitava Sur
- Faculty of Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC, Canada
- Department of Neonatal Perinatal Medicine, Children's and Women's Health Centre of British Columbia, 4480 Oak Street, Vancouver, BC V6H3V4, Canada
| | - Avash Singh
- Faculty of Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC, Canada
- Department of Neonatal Perinatal Medicine, Children's and Women's Health Centre of British Columbia, 4480 Oak Street, Vancouver, BC V6H3V4, Canada
| | - Derek G. Human
- Faculty of Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC, Canada
- Division of Pediatric Cardiology, Children's and Women's Health Centre of British Columbia, 4480 Oak Street, Room 1C50, Vancouver, BC V6H3V4, Canada
| | - Millan S. Patel
- Faculty of Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC, Canada
- Department of Medical Genetics and Child and Family Research Institute, Children's and Women's Health Centre of British Columbia, 4480 Oak Street, Room C234, Vancouver, BC V6H3V4, Canada
| | - Anna F. Lee
- Faculty of Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC, Canada
- Division of Anatomical Pathology, Children's and Women's Health Centre of British Columbia, and Department of Pathology and Laboratory Medicine, University of British Columbia, 4480 Oak Street, Room 2H47, Vancouver, BC V6H3V4, Canada
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Abstract
Systemic conditions may have pigmentary associations. Prompt recognition of these associations allows the practitioner to initiate the appropriate workup and therapy when indicated. This contribution highlights some of the clinical features of neurofibromatosis 1, LEOPARD syndrome, acanthosis nigricans, hypomelanosis of Ito, incontinentia pigmenti, CHILD syndrome, and piebaldism to assist the dermatologist in making the proper diagnosis.
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Affiliation(s)
- Patricia A Treadwell
- Department of Pediatrics, Indiana University School of Medicine, E3131 Fifth Third Office Building, 720 Eskenazi Avenue, Indianapolis, Indiana, 46202.
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30
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Hahn A, Lauriol J, Thul J, Behnke-Hall K, Logeswaran T, Schänzer A, Böğürcü N, Garvalov BK, Zenker M, Gelb BD, von Gerlach S, Kandolf R, Kontaridis MI, Schranz D. Rapidly progressive hypertrophic cardiomyopathy in an infant with Noonan syndrome with multiple lentigines: palliative treatment with a rapamycin analog. Am J Med Genet A 2015; 167A:744-51. [PMID: 25708222 DOI: 10.1002/ajmg.a.36982] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 01/02/2015] [Indexed: 12/16/2022]
Abstract
Noonan syndrome with multiple lentigines (NSML) frequently manifests with hypertrophic cardiomyopathy (HCM). Recently, it was demonstrated that mTOR inhibition reverses HCM in NSML mice. We report for the first time on the effects of treatment with a rapamycin analog in an infant with LS and malignant HCM. In the boy, progressive HCM was diagnosed during the first week of life and a diagnosis of NSML was established at age 20 weeks by showing a heterozygous Q510E mutation in PTPN11. Immunoblotting with antibodies against pERK, pAkt, and pS6RP in fibroblasts demonstrated enhanced Akt/mTOR pathway activity. Because of the patient's critical condition, everolimus therapy was started at age 24 weeks and continued until heart transplantation at age 36 weeks. Prior to surgery, heart failure improved from NYHA stage IV to II and brain natriuretic peptide values decreased from 9,600 to <1,000 pg/ml, but no reversal of cardiac hypertrophy was observed. Examination of the explanted heart revealed severe hypertrophy and myofiber disarray with extensive perivascular fibrosis. These findings provide evidence that Akt/mTOR activity is enhanced in NSML with HCM and suggest that rapamycin treatment could principally be feasible for infantile NSML. The preliminary experiences made in this single patient indicate that therapy should start early to prevent irreversible cardiac remodelling.
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Affiliation(s)
- Andreas Hahn
- Department of Child Neurology, University Hospital Giessen, Justus-Liebig University, Giessen, Germany
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31
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Riecken LB, Tawamie H, Dornblut C, Buchert R, Ismayel A, Schulz A, Schumacher J, Sticht H, Pohl KJ, Cui Y, Reis A, Morrison H, Abou Jamra R. Inhibition of RAS Activation Due to a Homozygous Ezrin Variant in Patients with Profound Intellectual Disability. Hum Mutat 2015; 36:270-8. [DOI: 10.1002/humu.22737] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 12/01/2014] [Indexed: 01/19/2023]
Affiliation(s)
- Lars Björn Riecken
- Leibniz Institute for Age Research; Fritz Lipmann Institute; Jena Germany
| | - Hasan Tawamie
- Institute of Human Genetics; Friedrich-Alexander-Universität Erlangen-Nürnberg; Erlangen Germany
| | - Carsten Dornblut
- Leibniz Institute for Age Research; Fritz Lipmann Institute; Jena Germany
| | - Rebecca Buchert
- Institute of Human Genetics; Friedrich-Alexander-Universität Erlangen-Nürnberg; Erlangen Germany
| | - Amina Ismayel
- Praxis of Pediatrics; Jesser El Sheghour; Idlib Syria
| | - Alexander Schulz
- Leibniz Institute for Age Research; Fritz Lipmann Institute; Jena Germany
| | | | - Heinrich Sticht
- Bioinformatics; Institute of Biochemistry; Friedrich-Alexander-Universität Erlangen-Nürnberg; Erlangen Germany
| | - Katja J. Pohl
- Leibniz Institute for Age Research; Fritz Lipmann Institute; Jena Germany
| | - Yan Cui
- Leibniz Institute for Age Research; Fritz Lipmann Institute; Jena Germany
| | - André Reis
- Institute of Human Genetics; Friedrich-Alexander-Universität Erlangen-Nürnberg; Erlangen Germany
| | - Helen Morrison
- Leibniz Institute for Age Research; Fritz Lipmann Institute; Jena Germany
| | - Rami Abou Jamra
- Institute of Human Genetics; Friedrich-Alexander-Universität Erlangen-Nürnberg; Erlangen Germany
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32
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Karaer K, Lissewski C, Zenker M. Familial cardiofaciocutaneous syndrome in a father and a son with a novel MEK2 mutation. Am J Med Genet A 2014; 167A:385-8. [DOI: 10.1002/ajmg.a.36429] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 12/08/2013] [Indexed: 11/11/2022]
Affiliation(s)
| | - Christina Lissewski
- Institute of Human Genetics; University Hospital Magdeburg and Medical Faculty of the Otto-von-Guericke University Magdeburg; Germany
| | - Martin Zenker
- Institute of Human Genetics; University Hospital Magdeburg and Medical Faculty of the Otto-von-Guericke University Magdeburg; Germany
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33
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Mechanism and treatment for learning and memory deficits in mouse models of Noonan syndrome. Nat Neurosci 2014; 17:1736-43. [PMID: 25383899 PMCID: PMC4716736 DOI: 10.1038/nn.3863] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2014] [Accepted: 10/14/2014] [Indexed: 12/31/2022]
Abstract
In Noonan Syndrome (NS) 30% to 50% of subjects show cognitive deficits of unknown etiology and with no known treatment. Here, we report that knock-in mice expressing either of two NS-associated Ptpn11 mutations show hippocampal-dependent spatial learning impairments and deficits in hippocampal long-term potentiation (LTP). In addition, viral overexpression of the PTPN11D61G in adult hippocampus results in increased baseline excitatory synaptic function, deficits in LTP and spatial learning, which can all be reversed by a MEK inhibitor. Furthermore, brief treatment with lovastatin reduces Ras-Erk activation in the brain, and normalizes the LTP and learning deficits in adult Ptpn11D61G/+ mice. Our results demonstrate that increased basal Erk activity and corresponding baseline increases in excitatory synaptic function are responsible for the LTP impairments and, consequently, the learning deficits in mouse models of NS. These data also suggest that lovastatin or MEK inhibitors may be useful for treating the cognitive deficits in NS.
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34
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van Engen-van Grunsven ACH, Kusters-Vandevelde H, Groenen PJTA, Blokx WAM. Update on Molecular Pathology of Cutaneous Melanocytic Lesions: What is New in Diagnosis and Molecular Testing for Treatment? Front Med (Lausanne) 2014; 1:39. [PMID: 25593912 PMCID: PMC4291896 DOI: 10.3389/fmed.2014.00039] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 08/26/2014] [Indexed: 01/01/2023] Open
Abstract
In this article, we give an update on recent findings regarding molecular pathology in cutaneous melanocytic tumors. The focus lies on use of genetics in the diagnosis of distinct subtypes of spitzoid tumors that are often characterized by specific phenotypic–genotypic alterations that can frequently be recognized by adequate histological examination. Typical illustrating cases are given in order to increase recognition of these lesions in daily dermatopathology practice. New molecular findings in the pathogenesis of congenital melanocytic tumors and neurocutaneous melanosis are reviewed. In addition, use of mutation analysis in the differential diagnosis of melanoma metastasis is discussed. Finally, application of mutation analysis in targeted therapy in advanced melanoma with advantages of new techniques such as next generation sequencing is described.
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Affiliation(s)
| | | | | | - Willeke A M Blokx
- Department of Pathology, Radboud University Medical Center , Nijmegen , Netherlands
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35
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Bülow L, Lissewski C, Bressel R, Rauch A, Stark Z, Zenker M, Bartsch O. Hydrops, fetal pleural effusions and chylothorax in three patients with CBL mutations. Am J Med Genet A 2014; 167A:394-9. [PMID: 25358541 DOI: 10.1002/ajmg.a.36838] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 09/27/2014] [Indexed: 11/05/2022]
Abstract
Fetal hydrops, fetal pleural effusions, hydrothorax, and chylothorax, may be associated with various genetic disorders, in particular with the Noonan, cardio-facio-cutaneous and Costello syndromes. These syndromes, collectively called RASopathies, are caused by mutations in the RAS/MAPK pathway, which is known to play a major role in lymphangiogenesis. Recently, germline mutations in the Casitas B-cell lymphoma (CBL) gene were reported in 25 patients and of these, 20 had juvenile myelomonocytic leukemia (JMML). The disorder was named "CBL syndrome" or "Noonan syndrome-like disorder with or without juvenile myelomonocytic leukemia" (NSLL). To date, prenatal abnormalities have not been reported and it is still debated whether the CBL syndrome falls into the category of a RASopathy, or represents a different entity. Here we report on three unrelated patients with CBL mutations manifesting with hydrops fetalis, fetal pleural effusions and/or congenital hydro-/chylothorax. Our findings further connect the CBL syndrome with the RASopathies.
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Affiliation(s)
- Luzie Bülow
- Institute of Human Genetics, University Medical Centre of the Johannes Gutenberg University, Mainz, Germany
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36
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Baldassarre G, Mussa A, Banaudi E, Rossi C, Tartaglia M, Silengo M, Ferrero GB. Phenotypic variability associated with the invariant SHOC2 c.4A>G (p.Ser2Gly) missense mutation. Am J Med Genet A 2014; 164A:3120-5. [PMID: 25331583 DOI: 10.1002/ajmg.a.36697] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 06/27/2014] [Indexed: 11/07/2022]
Abstract
Noonan-like syndrome with loose anagen hair (NS/LAH; OMIM 607721) is a developmental disorder clinically related to Noonan syndrome (NS) and characterized by facial dysmorphisms, postnatal growth retardation, cardiac anomalies (in particular dysplasia of the mitral valve and septal defects), variable neurocognitive impairment, and florid ectodermal features. A distinctive trait of NS/LAH is its association with easily pluckable, slow growing, sparse, and thin hair. This rare condition is due to the invariant c.4A > G missense (p.Ser2Gly) change in SHOC2, which encodes a regulatory protein that participate in RAS signaling. Here we report two patients with molecularly confirmed NS/LAH, with extremely different phenotypic expression, in particular concerning the severity of the cardiac phenotype and neurocognitive profile. While the first available clinical records outlined a relatively homogeneous phenotype in NS/LAH, the present data emphasize that the phenotype spectrum associated with this invariant mutation is wider than previously recognized.
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37
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Pierpont MEM, Magoulas PL, Adi S, Kavamura MI, Neri G, Noonan J, Pierpont EI, Reinker K, Roberts AE, Shankar S, Sullivan J, Wolford M, Conger B, Santa Cruz M, Rauen KA. Cardio-facio-cutaneous syndrome: clinical features, diagnosis, and management guidelines. Pediatrics 2014; 134:e1149-62. [PMID: 25180280 PMCID: PMC4179092 DOI: 10.1542/peds.2013-3189] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/23/2014] [Indexed: 12/22/2022] Open
Abstract
Cardio-facio-cutaneous syndrome (CFC) is one of the RASopathies that bears many clinical features in common with the other syndromes in this group, most notably Noonan syndrome and Costello syndrome. CFC is genetically heterogeneous and caused by gene mutations in the Ras/mitogen-activated protein kinase pathway. The major features of CFC include characteristic craniofacial dysmorphology, congenital heart disease, dermatologic abnormalities, growth retardation, and intellectual disability. It is essential that this condition be differentiated from other RASopathies, as a correct diagnosis is important for appropriate medical management and determining recurrence risk. Children and adults with CFC require multidisciplinary care from specialists, and the need for comprehensive management has been apparent to families and health care professionals caring for affected individuals. To address this need, CFC International, a nonprofit family support organization that provides a forum for information, support, and facilitation of research in basic medical and social issues affecting individuals with CFC, organized a consensus conference. Experts in multiple medical specialties provided clinical management guidelines for pediatricians and other care providers. These guidelines will assist in an accurate diagnosis of individuals with CFC, provide best practice recommendations, and facilitate long-term medical care.
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Affiliation(s)
- Mary Ella M Pierpont
- Division of Genetics and Metabolism, Department of Pediatrics and Ophthalmology, and Children's Hospitals and Clinics of Minnesota, Saint Paul, Minnesota;
| | - Pilar L Magoulas
- Department of Molecular and Human Genetics, Texas Children's Hospital and Baylor College of Medicine, Houston, Texas
| | - Saleh Adi
- Madison Clinic for Pediatric Diabetes, Benioff Children's Hospital and University of California at San Francisco, San Francisco, California
| | | | - Giovanni Neri
- Institute of Medical Genetics, A Gemelli School of Medicine, Catholic University, Rome, Italy
| | - Jacqueline Noonan
- Department of Pediatrics, University of Kentucky, Lexington, Kentucky
| | - Elizabeth I Pierpont
- Division of Clinical Behavioral Neuroscience, Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota
| | - Kent Reinker
- Department of Orthopedics, University of Texas Health Sciences Center, San Antonio, Texas
| | - Amy E Roberts
- Department of Cardiology and Division of Genetics, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Suma Shankar
- Departments of Human Genetics and Ophthalmology, Emory University School of Medicine, Atlanta, Georgia
| | - Joseph Sullivan
- Departments of Neurology and Pediatrics, University of California at San Francisco, San Francisco, California
| | - Melinda Wolford
- Department of Counseling, Special Education and School Psychology, Youngstown State University, Youngstown, Ohio
| | | | | | - Katherine A Rauen
- Division of Genomic Medicine, Department of Pediatrics, UC Davis MIND Institute, University of California at Davis, Sacramento, California
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38
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Kadam P, Rand J, Rady P, Tyring S, Stehlik J, Sedivcova M, Kazakov DV, Ray K, Hill J, Agag R, Carlson JA. Adolescent Onset of Localized Papillomatosis, Lymphedema, and Multiple Beta-Papillomavirus Infection: Epidermal Nevus, Segmental Lymphedema Praecox, or Verrucosis? A Case Report and Case Series of Epidermal Nevi. Dermatopathology (Basel) 2014; 1:55-69. [PMID: 27047923 PMCID: PMC4772932 DOI: 10.1159/000367967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Herein, we report the case of a 12-year-old female who noted the recent onset of an oval, circumscribed, 10-cm papillomatous plaque affecting the thigh and vulva that showed histologic signs of lymphedema without evidence of secondary lymphedema. The sequencing of genes associated with a delayed onset of lymphedema or epidermal nevi (EN) - GATA2 and GJC2, and HRAS and KRAS, respectively - showed wild-type alleles. Polymerase chain reaction for human papillomavirus (HPV) DNA demonstrated infections with 15 HPV genotypes. Evidence of productive HPV infection, HPV capsid expression, and cytopathic changes was detected. At the 6-month follow-up, no evidence of recurrence was found after complete excision. The analysis of a consecutive series of 91 EN excision specimens revealed that 76% exhibited histologic evidence of lymphostasis. Notably, multiple acrochordon-like EN, which most closely resembled this case, showed similar signs of localized lymphedema. The late onset and evidence of lymphedema favors the diagnosis of congenital unisegmental lymphedema. However, the clinical findings and epidermal changes point to the diagnosis of EN. Moreover, localized verrucosis also accurately describes this patient's cutaneous findings. Based on the above evidence, we postulate that an abnormal development of lymphatics may play a primary role in the pathogenesis of some types of EN and facilitate productive HPV infection.
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Affiliation(s)
- Pooja Kadam
- Department of Pathology, Albany Medical College, Albany, N.Y., USA
| | - Janne Rand
- Department of Pathology, Albany Medical College, Albany, N.Y., USA
| | - Peter Rady
- Department of Dermatology, University of Texas Health Science Center, Houston, Tex., USA
- Department of Microbiology/Medical Genetics, University of Texas Health Science Center, Houston, Tex., USA
- Department of Internal Medicine, University of Texas Health Science Center, Houston, Tex., USA
| | - Stephen Tyring
- Department of Dermatology, University of Texas Health Science Center, Houston, Tex., USA
- Department of Microbiology/Medical Genetics, University of Texas Health Science Center, Houston, Tex., USA
- Department of Internal Medicine, University of Texas Health Science Center, Houston, Tex., USA
| | - Jan Stehlik
- Department of Pathology, Medical Faculty in Pilsen, Charles University, Pilsen, Czech Republic
| | - Monica Sedivcova
- Department of Pathology, Medical Faculty in Pilsen, Charles University, Pilsen, Czech Republic
| | - Dmitry V. Kazakov
- Department of Pathology, Medical Faculty in Pilsen, Charles University, Pilsen, Czech Republic
| | - Kathy Ray
- Department of Capital District Dermatology, Glenmont, N.Y., USA
| | - Jerome Hill
- Department of Capital District Dermatology, Glenmont, N.Y., USA
| | - Richard Agag
- Department of Plastic Surgery, Albany Medical College, Albany, N.Y., USA
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Kelly ML, Astsaturov A, Rhodes J, Chernoff J. A Pak1/Erk signaling module acts through Gata6 to regulate cardiovascular development in zebrafish. Dev Cell 2014; 29:350-9. [PMID: 24823378 DOI: 10.1016/j.devcel.2014.04.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 01/31/2014] [Accepted: 04/01/2014] [Indexed: 01/12/2023]
Abstract
Proper neural crest development and migration is critical during embryonic development, but the molecular mechanisms regulating this process remain incompletely understood. Here, we show that the protein kinase Erk, which plays a central role in a number of key developmental processes in vertebrates, is regulated in the developing neural crest by p21-activated protein kinase 1 (Pak1). Furthermore, we show that activated Erk signals by phosphorylating the transcription factor Gata6 on a conserved serine residue to promote neural crest migration and proper formation of craniofacial structures, pigment cells, and the outflow tract of the heart. Our data suggest an essential role for Pak1 as an Erk activator, and Gata6 as an Erk target, during neural crest development.
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Affiliation(s)
- Mollie L Kelly
- Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, PA 19111, USA; Department of Biochemistry and Molecular Biology, Drexel University, Philadelphia, PA 19102, USA
| | - Artyom Astsaturov
- Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Jennifer Rhodes
- Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Jonathan Chernoff
- Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
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Martin HC, Kim GE, Pagnamenta AT, Murakami Y, Carvill GL, Meyer E, Copley RR, Rimmer A, Barcia G, Fleming MR, Kronengold J, Brown MR, Hudspith KA, Broxholme J, Kanapin A, Cazier JB, Kinoshita T, Nabbout R, Bentley D, McVean G, Heavin S, Zaiwalla Z, McShane T, Mefford HC, Shears D, Stewart H, Kurian MA, Scheffer IE, Blair E, Donnelly P, Kaczmarek LK, Taylor JC. Clinical whole-genome sequencing in severe early-onset epilepsy reveals new genes and improves molecular diagnosis. Hum Mol Genet 2014; 23:3200-11. [PMID: 24463883 PMCID: PMC4030775 DOI: 10.1093/hmg/ddu030] [Citation(s) in RCA: 188] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 01/20/2014] [Indexed: 11/13/2022] Open
Abstract
In severe early-onset epilepsy, precise clinical and molecular genetic diagnosis is complex, as many metabolic and electro-physiological processes have been implicated in disease causation. The clinical phenotypes share many features such as complex seizure types and developmental delay. Molecular diagnosis has historically been confined to sequential testing of candidate genes known to be associated with specific sub-phenotypes, but the diagnostic yield of this approach can be low. We conducted whole-genome sequencing (WGS) on six patients with severe early-onset epilepsy who had previously been refractory to molecular diagnosis, and their parents. Four of these patients had a clinical diagnosis of Ohtahara Syndrome (OS) and two patients had severe non-syndromic early-onset epilepsy (NSEOE). In two OS cases, we found de novo non-synonymous mutations in the genes KCNQ2 and SCN2A. In a third OS case, WGS revealed paternal isodisomy for chromosome 9, leading to identification of the causal homozygous missense variant in KCNT1, which produced a substantial increase in potassium channel current. The fourth OS patient had a recessive mutation in PIGQ that led to exon skipping and defective glycophosphatidyl inositol biosynthesis. The two patients with NSEOE had likely pathogenic de novo mutations in CBL and CSNK1G1, respectively. Mutations in these genes were not found among 500 additional individuals with epilepsy. This work reveals two novel genes for OS, KCNT1 and PIGQ. It also uncovers unexpected genetic mechanisms and emphasizes the power of WGS as a clinical tool for making molecular diagnoses, particularly for highly heterogeneous disorders.
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Affiliation(s)
- Hilary C Martin
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Grace E Kim
- Departments of Cellular and Molecular Physiology and Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Alistair T Pagnamenta
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK, NIHR Biomedical Research Centre, Oxford, UK
| | - Yoshiko Murakami
- Department of Immunoregulation, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Gemma L Carvill
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA, USA
| | - Esther Meyer
- Neurosciences Unit, UCL-Institute of Child Health, London, UK, Department of Neurology, Great Ormond Street Hospital, London, UK
| | - Richard R Copley
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK, NIHR Biomedical Research Centre, Oxford, UK
| | - Andrew Rimmer
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Giulia Barcia
- Department of Paediatric Neurology, Centre de Reference Epilepsies Rares, Hôpital Necker-Enfants Malades, Paris, France
| | - Matthew R Fleming
- Departments of Cellular and Molecular Physiology and Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Jack Kronengold
- Departments of Cellular and Molecular Physiology and Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Maile R Brown
- Departments of Cellular and Molecular Physiology and Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Karl A Hudspith
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK, NIHR Biomedical Research Centre, Oxford, UK
| | - John Broxholme
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Alexander Kanapin
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Taroh Kinoshita
- Department of Immunoregulation, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Rima Nabbout
- Department of Paediatric Neurology, Centre de Reference Epilepsies Rares, Hôpital Necker-Enfants Malades, Paris, France
| | | | - Gil McVean
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Sinéad Heavin
- Departments of Medicine and Paediatrics, Florey Institute, The University of Melbourne, Austin Health and Royal Children's Hospital, Melbourne, VIC, Australia
| | - Zenobia Zaiwalla
- Department of Clinical Neurophysiology, John Radcliffe Hospital, Oxford, UK
| | - Tony McShane
- Department of Paediatrics, Children's Hospital Oxford, John Radcliffe Hospital, Oxford, UK
| | - Heather C Mefford
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA, USA
| | - Deborah Shears
- Department of Clinical Genetics, Oxford University Hospitals NHS Trust, Oxford, UK
| | - Helen Stewart
- Department of Clinical Genetics, Oxford University Hospitals NHS Trust, Oxford, UK
| | - Manju A Kurian
- Neurosciences Unit, UCL-Institute of Child Health, London, UK
| | - Ingrid E Scheffer
- Departments of Medicine and Paediatrics, Florey Institute, The University of Melbourne, Austin Health and Royal Children's Hospital, Melbourne, VIC, Australia
| | - Edward Blair
- Department of Clinical Genetics, Oxford University Hospitals NHS Trust, Oxford, UK
| | - Peter Donnelly
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Leonard K Kaczmarek
- Departments of Cellular and Molecular Physiology and Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Jenny C Taylor
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK, NIHR Biomedical Research Centre, Oxford, UK,
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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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Ekvall S, Sjörs K, Jonzon A, Vihinen M, Annerén G, Bondeson ML. Novel association of neurofibromatosis type 1-causing mutations in families with neurofibromatosis-Noonan syndrome. Am J Med Genet A 2013; 164A:579-87. [PMID: 24357598 DOI: 10.1002/ajmg.a.36313] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 09/29/2013] [Indexed: 11/10/2022]
Abstract
Neurofibromatosis-Noonan syndrome (NFNS) is a rare condition with clinical features of both neurofibromatosis type 1 (NF1) and Noonan syndrome (NS). All three syndromes belong to the RASopathies, which are caused by dysregulation of the RAS-MAPK pathway. The major gene involved in NFNS is NF1, but co-occurring NF1 and PTPN11 mutations in NFNS have been reported. Knowledge about possible involvement of additional RASopathy-associated genes in NFNS is, however, very limited. We present a comprehensive clinical and molecular analysis of eight affected individuals from three unrelated families displaying features of NF1 and NFNS. The genetic etiology of the clinical phenotypes was investigated by mutation analysis, including NF1, PTPN11, SOS1, KRAS, NRAS, BRAF, RAF1, SHOC2, SPRED1, MAP2K1, MAP2K2, and CBL. All three families harbored a heterozygous NF1 variant, where the first family had a missense variant, c.5425C>T;p.R1809C, the second family a recurrent 4bp-deletion, c.6789_6792delTTAC;p.Y2264Tfs*6, and the third family a splice-site variant, c.2991-1G>A, resulting in skipping of exon 18 and an in-frame deletion of 41 amino acids. These NF1 variants have all previously been reported in NF1 patients. Surprisingly, both c.6789_6792delTTAC and c.2991-1G>A are frequently associated with NF1, but association to NFNS has, to our knowledge, not previously been reported. Our results support the notion that NFNS represents a variant of NF1, genetically distinct from NS, and is caused by mutations in NF1, some of which also cause classical NF1. Due to phenotypic overlap between NFNS and NS, we propose screening for NF1 mutations in NS patients, preferentially when café-au-lait spots are present.
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Affiliation(s)
- Sara Ekvall
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
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Genetic and functional studies implicate synaptic overgrowth and ring gland cAMP/PKA signaling defects in the Drosophila melanogaster neurofibromatosis-1 growth deficiency. PLoS Genet 2013; 9:e1003958. [PMID: 24278035 PMCID: PMC3836801 DOI: 10.1371/journal.pgen.1003958] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 10/01/2013] [Indexed: 12/21/2022] Open
Abstract
Neurofibromatosis type 1 (NF1), a genetic disease that affects 1 in 3,000, is caused by loss of a large evolutionary conserved protein that serves as a GTPase Activating Protein (GAP) for Ras. Among Drosophila melanogaster Nf1 (dNf1) null mutant phenotypes, learning/memory deficits and reduced overall growth resemble human NF1 symptoms. These and other dNf1 defects are relatively insensitive to manipulations that reduce Ras signaling strength but are suppressed by increasing signaling through the 3′-5′ cyclic adenosine monophosphate (cAMP) dependent Protein Kinase A (PKA) pathway, or phenocopied by inhibiting this pathway. However, whether dNf1 affects cAMP/PKA signaling directly or indirectly remains controversial. To shed light on this issue we screened 486 1st and 2nd chromosome deficiencies that uncover >80% of annotated genes for dominant modifiers of the dNf1 pupal size defect, identifying responsible genes in crosses with mutant alleles or by tissue-specific RNA interference (RNAi) knockdown. Validating the screen, identified suppressors include the previously implicated dAlk tyrosine kinase, its activating ligand jelly belly (jeb), two other genes involved in Ras/ERK signal transduction and several involved in cAMP/PKA signaling. Novel modifiers that implicate synaptic defects in the dNf1 growth deficiency include the intersectin-related synaptic scaffold protein Dap160 and the cholecystokinin receptor-related CCKLR-17D1 drosulfakinin receptor. Providing mechanistic clues, we show that dAlk, jeb and CCKLR-17D1 are among mutants that also suppress a recently identified dNf1 neuromuscular junction (NMJ) overgrowth phenotype and that manipulations that increase cAMP/PKA signaling in adipokinetic hormone (AKH)-producing cells at the base of the neuroendocrine ring gland restore the dNf1 growth deficiency. Finally, supporting our previous contention that ALK might be a therapeutic target in NF1, we report that human ALK is expressed in cells that give rise to NF1 tumors and that NF1 regulated ALK/RAS/ERK signaling appears conserved in man. Neurofibromatosis type 1 (NF1) is a genetic disease that affects 1 in 3,000 and that is caused by loss of a protein that inactivates Ras oncoproteins. NF1 is a characteristically variable disease that predisposes patients to several symptoms, the most common of which include benign and malignant tumors, reduced growth and learning problems. We and others previously found that fruit fly mutants that lack a highly conserved dNf1 gene are reduced in size and exhibit impaired learning and memory, and that both defects appear due to abnormal Ras and cyclic-AMP (cAMP) signaling. The former was unremarkable, but how loss of dNf1 affects cAMP signaling remains poorly understood. Here we report results of a genetic screen for dominant modifiers of the dNf1 growth defect. This screen and follow-up functional studies support a model in which synaptic defects and reduced cAMP signaling in specific parts of the neuroendocrine ring gland contribute to the dNf1 growth defect. Beyond these results, we show that human ALK is expressed in cells that give rise to NF1 tumors, and that NF1 regulated ALK/RAS/ERK signaling is evolutionary conserved.
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Pierpont EI, Tworog-Dube E, Roberts AE. Learning and memory in children with Noonan syndrome. Am J Med Genet A 2013; 161A:2250-7. [PMID: 23918208 PMCID: PMC9923801 DOI: 10.1002/ajmg.a.36075] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Accepted: 05/03/2013] [Indexed: 02/05/2023]
Abstract
Genetic syndromes resulting from molecular alterations of the RAS-MAPK signaling cascade have become the focus of heightened interest among behavioral scientists due to discoveries that proteins within this pathway play an important role in memory formation and consolidation. Individuals with Noonan syndrome (NS), caused by germline mutations in the RAS-MAPK pathway, exhibit wide variability in cognitive and memory skills. The current study aimed to characterize memory deficits that occur in some affected individuals as a key step toward understanding the neurocognitive effects of dysregulated Ras signaling. Learning and memory skills were assessed among 29 children and adolescents with NS using the Wide Range Assessment of Memory and Learning, Second Edition. Performance across subdomains (verbal memory, visual memory and working memory) was compared, as well as the effect of response type (free recall vs. recognition). For immediate memory, children with NS performed significantly better on verbal memory tasks than on visual memory or working memory tasks. For delayed memory, verbal free recall tasks that depend heavily on prefrontal-hippocampal networks were more challenging than recognition tasks that rely on more distributed temporal cortical regions. Additionally, verbal information presented in context was more easily retained than that presented in a rote format. The current study contributes to our knowledge of the effects of dysregulated RAS-MAPK signaling on the brain and behavior. Continued research on neurocognitive skills in NS has the potential to generate a novel conceptualization of how learning disabilities can arise from altered molecular processes within a specific biological pathway.
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Affiliation(s)
- Elizabeth I. Pierpont
- Department of Cardiology; Boston Children's Hospital; Massachusetts
- Department of Pediatrics; University of Minnesota Medical School; Boston Children's Hospital; Boston Massachusetts
| | - Erica Tworog-Dube
- Division of Genetics; Boston Children's Hospital; Boston Massachusetts
| | - Amy E. Roberts
- Department of Cardiology; Boston Children's Hospital; Massachusetts
- Division of Genetics; Boston Children's Hospital; Boston Massachusetts
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Jones DTW, Hutter B, Jäger N, Korshunov A, Kool M, Warnatz HJ, Zichner T, Lambert SR, Ryzhova M, Quang DAK, Fontebasso AM, Stütz AM, Hutter S, Zuckermann M, Sturm D, Gronych J, Lasitschka B, Schmidt S, Seker-Cin H, Witt H, Sultan M, Ralser M, Northcott PA, Hovestadt V, Bender S, Pfaff E, Stark S, Faury D, Schwartzentruber J, Majewski J, Weber UD, Zapatka M, Raeder B, Schlesner M, Worth CL, Bartholomae CC, von Kalle C, Imbusch CD, Radomski S, Lawerenz C, van Sluis P, Koster J, Volckmann R, Versteeg R, Lehrach H, Monoranu C, Winkler B, Unterberg A, Herold-Mende C, Milde T, Kulozik AE, Ebinger M, Schuhmann MU, Cho YJ, Pomeroy SL, von Deimling A, Witt O, Taylor MD, Wolf S, Karajannis MA, Eberhart CG, Scheurlen W, Hasselblatt M, Ligon KL, Kieran MW, Korbel JO, Yaspo ML, Brors B, Felsberg J, Reifenberger G, Collins VP, Jabado N, Eils R, Lichter P, Pfister SM. Recurrent somatic alterations of FGFR1 and NTRK2 in pilocytic astrocytoma. Nat Genet 2013; 45:927-32. [PMID: 23817572 DOI: 10.1038/ng.2682] [Citation(s) in RCA: 580] [Impact Index Per Article: 52.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 06/03/2013] [Indexed: 02/08/2023]
Abstract
Pilocytic astrocytoma, the most common childhood brain tumor, is typically associated with mitogen-activated protein kinase (MAPK) pathway alterations. Surgically inaccessible midline tumors are therapeutically challenging, showing sustained tendency for progression and often becoming a chronic disease with substantial morbidities. Here we describe whole-genome sequencing of 96 pilocytic astrocytomas, with matched RNA sequencing (n = 73), conducted by the International Cancer Genome Consortium (ICGC) PedBrain Tumor Project. We identified recurrent activating mutations in FGFR1 and PTPN11 and new NTRK2 fusion genes in non-cerebellar tumors. New BRAF-activating changes were also observed. MAPK pathway alterations affected all tumors analyzed, with no other significant mutations identified, indicating that pilocytic astrocytoma is predominantly a single-pathway disease. Notably, we identified the same FGFR1 mutations in a subset of H3F3A-mutated pediatric glioblastoma with additional alterations in the NF1 gene. Our findings thus identify new potential therapeutic targets in distinct subsets of pilocytic astrocytoma and childhood glioblastoma.
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Affiliation(s)
- David T W Jones
- Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), Heidelberg, Germany
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What's new in pediatric dermatology? J Am Acad Dermatol 2013; 68:885.e1-12; quiz 897-8. [DOI: 10.1016/j.jaad.2013.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 03/13/2013] [Accepted: 03/15/2013] [Indexed: 11/22/2022]
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Abstract
PURPOSE OF REVIEW The recognition that apoptosis - programmed cell death - is an important mechanism in immune homeostasis has led to the identification of human disorders associated with defects in the critical control mechanism. RECENT FINDINGS Patients have been identified with defects affecting the extrinsic apoptotic pathway mediated by the protein receptor FAS which results in the autoimmune lymphoproliferative syndrome and more recently in defects affecting the intrinsic apoptotic pathway mediated by RAS proteins resulting in the RAS-associated autoimmune leukoproliferative disorder. This review summarizes the immunopathogenesis, clinical features and diagnostic approaches to these human disorders. SUMMARY Apoptotic pathways are critical in the maintenance of leukocyte homeostasis, and genetic defects impacting these can result in clinical disease manifested as expansion of selected leukocyte populations, autoimmunity, increased risk for malignancy and in some situations defects in host defense.
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Harmon RM, Simpson CL, Johnson JL, Koetsier JL, Dubash AD, Najor NA, Sarig O, Sprecher E, Green KJ. Desmoglein-1/Erbin interaction suppresses ERK activation to support epidermal differentiation. J Clin Invest 2013; 123:1556-70. [PMID: 23524970 DOI: 10.1172/jci65220] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 01/17/2013] [Indexed: 01/27/2023] Open
Abstract
Genetic disorders of the Ras/MAPK pathway, termed RASopathies, produce numerous abnormalities, including cutaneous keratodermas. The desmosomal cadherin, desmoglein-1 (DSG1), promotes keratinocyte differentiation by attenuating MAPK/ERK signaling and is linked to striate palmoplantar keratoderma (SPPK). This raises the possibility that cutaneous defects associated with SPPK and RASopathies share certain molecular faults. To identify intermediates responsible for executing the inhibition of ERK by DSG1, we conducted a yeast 2-hybrid screen. The screen revealed that Erbin (also known as ERBB2IP), a known ERK regulator, binds DSG1. Erbin silencing disrupted keratinocyte differentiation in culture, mimicking aspects of DSG1 deficiency. Furthermore, ERK inhibition and the induction of differentiation markers by DSG1 required both Erbin and DSG1 domains that participate in binding Erbin. Erbin blocks ERK signaling by interacting with and disrupting Ras-Raf scaffolds mediated by SHOC2, a protein genetically linked to the RASopathy, Noonan-like syndrome with loose anagen hair (NS/LAH). DSG1 overexpression enhanced this inhibitory function, increasing Erbin-SHOC2 interactions and decreasing Ras-SHOC2 interactions. Conversely, analysis of epidermis from DSG1-deficient patients with SPPK demonstrated increased Ras-SHOC2 colocalization and decreased Erbin-SHOC2 colocalization, offering a possible explanation for the observed epidermal defects. These findings suggest a mechanism by which DSG1 and Erbin cooperate to repress MAPK signaling and promote keratinocyte differentiation.
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Affiliation(s)
- Robert M Harmon
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, USA
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Kinsler VA, Thomas AC, Ishida M, Bulstrode NW, Loughlin S, Hing S, Chalker J, McKenzie K, Abu-Amero S, Slater O, Chanudet E, Palmer R, Morrogh D, Stanier P, Healy E, Sebire NJ, Moore GE. Multiple congenital melanocytic nevi and neurocutaneous melanosis are caused by postzygotic mutations in codon 61 of NRAS. J Invest Dermatol 2013; 133:2229-36. [PMID: 23392294 PMCID: PMC3678977 DOI: 10.1038/jid.2013.70] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 12/06/2012] [Accepted: 01/02/2013] [Indexed: 01/01/2023]
Abstract
Congenital melanocytic nevi (CMN) can be associated with neurological abnormalities and an increased risk of melanoma. Mutations in NRAS, BRAF, and Tp53 have been described in individual CMN samples; however, their role in the pathogenesis of multiple CMN within the same subject and development of associated features has not been clear. We hypothesized that a single postzygotic mutation in NRAS could be responsible for multiple CMN in the same individual, as well as for melanocytic and nonmelanocytic central nervous system (CNS) lesions. From 15 patients, 55 samples with multiple CMN were sequenced after site-directed mutagenesis and enzymatic digestion of the wild-type allele. Oncogenic missense mutations in codon 61 of NRAS were found in affected neurological and cutaneous tissues of 12 out of 15 patients, but were absent from unaffected tissues and blood, consistent with NRAS mutation mosaicism. In 10 patients, the mutation was consistently c.181C>A, p.Q61K, and in 2 patients c.182A>G, p.Q61R. All 11 non-melanocytic and melanocytic CNS samples from 5 patients were mutation positive, despite NRAS rarely being reported as mutated in CNS tumors. Loss of heterozygosity was associated with the onset of melanoma in two cases, implying a multistep progression to malignancy. These results suggest that single postzygotic NRAS mutations are responsible for multiple CMN and associated neurological lesions in the majority of cases.
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Affiliation(s)
- Veronica A Kinsler
- Paediatric Dermatology Department, Great Ormond Street Hospital for Children, London, UK.
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