151
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Gripp KW, Bifeld E, Stabley DL, Hopkins E, Meien S, Vinette K, Sol-Church K, Rosenberger G. A novel HRAS substitution (c.266C>G; p.S89C) resulting in decreased downstream signaling suggests a new dimension of RAS pathway dysregulation in human development. Am J Med Genet A 2012; 158A:2106-18. [PMID: 22821884 DOI: 10.1002/ajmg.a.35449] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 04/08/2012] [Indexed: 12/13/2022]
Abstract
Costello syndrome is caused by HRAS germline mutations affecting Gly(12) or Gly(13) in >90% of cases and these are associated with a relatively homogeneous phenotype. Rarer mutations in other HRAS codons were reported in patients with an attenuated or mild phenotype. Disease-associated HRAS missense mutations result in constitutive HRAS activation and increased RAF-MEK-ERK and PI3K-AKT signal flow. Here we report on a novel heterozygous HRAS germline alteration, c.266C>G (p.S89C), in a girl presenting with severe fetal hydrops and pleural effusion, followed by a more benign postnatal course. A sibling with the same mutation and fetal polyhydramnios showed a Dandy-Walker malformation; his postnatal course was complicated by severe feeding difficulties. Their apparently asymptomatic father is heterozygous for the c.266C>G change. By functional analyses we identified reduced levels of active HRAS(S89C) and diminished MEK, ERK and AKT phosphorylation in cells overexpressing HRAS(S89C) , which represent novel consequences of disease-associated HRAS mutations. Given our patients' difficult neonatal course and presence of this change in their asymptomatic father, we hypothesize that its harmful consequences may be time limited, with the late fetal stage being most sensitive. Alternatively, the phenotype may develop only in the presence of an additional as-yet-unknown genetic modifier. While the pathogenicity of the HRAS c.266C>G change remains unproven, our data may illustrate wide functional and phenotypic variability of germline HRAS mutations.
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Affiliation(s)
- Karen W Gripp
- Division of Medical Genetics, A. I. duPont Hospital for Children, Wilmington, Delaware, USA
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152
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Jones DTW, Gronych J, Lichter P, Witt O, Pfister SM. MAPK pathway activation in pilocytic astrocytoma. Cell Mol Life Sci 2012; 69:1799-811. [PMID: 22159586 PMCID: PMC3350769 DOI: 10.1007/s00018-011-0898-9] [Citation(s) in RCA: 157] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Revised: 11/22/2011] [Accepted: 11/24/2011] [Indexed: 12/31/2022]
Abstract
Pilocytic astrocytoma (PA) is the most common tumor of the pediatric central nervous system (CNS). A body of research over recent years has demonstrated a key role for mitogen-activated protein kinase (MAPK) pathway signaling in the development and behavior of PAs. Several mechanisms lead to activation of this pathway in PA, mostly in a mutually exclusive manner, with constitutive BRAF kinase activation subsequent to gene fusion being the most frequent. The high specificity of this fusion to PA when compared with other CNS tumors has diagnostic utility. In addition, the frequency of alteration of this key pathway provides an opportunity for molecularly targeted therapy in this tumor. Here, we review the current knowledge on mechanisms of MAPK activation in PA and some of the downstream consequences of this activation, which are now starting to be elucidated both in vitro and in vivo, as well as clinical considerations and possible future directions.
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Affiliation(s)
- David T. W. Jones
- Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Jan Gronych
- Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Peter Lichter
- Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Olaf Witt
- Department of Pediatric Oncology, Hematology and Immunology, University Hospital Heidelberg, Im Neuenheimer Feld 430, 69120 Heidelberg, Germany
- Clinical Cooperation Unit Pediatric Oncology, DKFZ, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Stefan M. Pfister
- Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
- Department of Pediatric Oncology, Hematology and Immunology, University Hospital Heidelberg, Im Neuenheimer Feld 430, 69120 Heidelberg, Germany
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153
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Saito Y, Aoki Y, Muramatsu H, Makishima H, Maciejewski JP, Imaizumi M, Rikiishi T, Sasahara Y, Kure S, Niihori T, Tsuchiya S, Kojima S, Matsubara Y. Casitas B-cell lymphoma mutation in childhood T-cell acute lymphoblastic leukemia. Leuk Res 2012; 36:1009-15. [PMID: 22591685 DOI: 10.1016/j.leukres.2012.04.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 04/01/2012] [Accepted: 04/16/2012] [Indexed: 10/28/2022]
Abstract
Somatic CBL mutations have been reported in a variety of myeloid neoplasms but are rare in acute lymphoblastic leukemia (ALL). We analyzed 77 samples from hematologic malignancies, identifying a somatic mutation in CBL (p.C381R) in one patient with T-ALL that was associated with a uniparental disomy at the CBL locus and a germline heterozygous mutation in one patient with JMML. Two NOTCH1 mutations and homozygous deletions in LEF1 and CDKN2A were identified in T-ALL cells. The activation of the RAS pathway was enhanced, and activation of the NOTCH1 pathway was inhibited in NIH 3T3 cells that expressed p.C381R. This study appears to be the first to identify a CBL mutation in T-ALL.
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Affiliation(s)
- Yuka Saito
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan
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154
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Kelleher RJ, Geigenmüller U, Hovhannisyan H, Trautman E, Pinard R, Rathmell B, Carpenter R, Margulies D. High-throughput sequencing of mGluR signaling pathway genes reveals enrichment of rare variants in autism. PLoS One 2012; 7:e35003. [PMID: 22558107 PMCID: PMC3338748 DOI: 10.1371/journal.pone.0035003] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Accepted: 03/08/2012] [Indexed: 12/11/2022] Open
Abstract
Identification of common molecular pathways affected by genetic variation in autism is important for understanding disease pathogenesis and devising effective therapies. Here, we test the hypothesis that rare genetic variation in the metabotropic glutamate-receptor (mGluR) signaling pathway contributes to autism susceptibility. Single-nucleotide variants in genes encoding components of the mGluR signaling pathway were identified by high-throughput multiplex sequencing of pooled samples from 290 non-syndromic autism cases and 300 ethnically matched controls on two independent next-generation platforms. This analysis revealed significant enrichment of rare functional variants in the mGluR pathway in autism cases. Higher burdens of rare, potentially deleterious variants were identified in autism cases for three pathway genes previously implicated in syndromic autism spectrum disorder, TSC1, TSC2, and SHANK3, suggesting that genetic variation in these genes also contributes to risk for non-syndromic autism. In addition, our analysis identified HOMER1, which encodes a postsynaptic density-localized scaffolding protein that interacts with Shank3 to regulate mGluR activity, as a novel autism-risk gene. Rare, potentially deleterious HOMER1 variants identified uniquely in the autism population affected functionally important protein regions or regulatory sequences and co-segregated closely with autism among children of affected families. We also identified rare ASD-associated coding variants predicted to have damaging effects on components of the Ras/MAPK cascade. Collectively, these findings suggest that altered signaling downstream of mGluRs contributes to the pathogenesis of non-syndromic autism.
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Affiliation(s)
- Raymond J Kelleher
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America.
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155
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Wefers B, Hitz C, Hölter SM, Trümbach D, Hansen J, Weber P, Pütz B, Deussing JM, de Angelis MH, Roenneberg T, Zheng F, Alzheimer C, Silva A, Wurst W, Kühn R. MAPK signaling determines anxiety in the juvenile mouse brain but depression-like behavior in adults. PLoS One 2012; 7:e35035. [PMID: 22529971 PMCID: PMC3329550 DOI: 10.1371/journal.pone.0035035] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Accepted: 03/08/2012] [Indexed: 11/18/2022] Open
Abstract
MAP kinase signaling has been implicated in brain development, long-term memory, and the response to antidepressants. Inducible Braf knockout mice, which exhibit protein depletion in principle forebrain neurons, enabled us to unravel a new role of neuronal MAPK signaling for emotional behavior. Braf mice that were induced during adulthood showed normal anxiety but increased depression-like behavior, in accordance with pharmacological findings. In contrast, the inducible or constitutive inactivation of Braf in the juvenile brain leads to normal depression-like behavior but decreased anxiety in adults. In juvenile, constitutive mutants we found no alteration of GABAergic neurotransmission but reduced neuronal arborization in the dentate gyrus. Analysis of gene expression in the hippocampus revealed nine downregulated MAPK target genes that represent candidates to cause the mutant phenotype. Our results reveal the differential function of MAPK signaling in juvenile and adult life phases and emphasize the early postnatal period as critical for the determination of anxiety in adults. Moreover, these results validate inducible gene inactivation as a new valuable approach, allowing it to discriminate between gene function in the adult and the developing postnatal brain.
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Affiliation(s)
- Benedikt Wefers
- German Research Center for Environmental Health, Institute of Developmental Genetics, Helmholtz Zentrum München, Neuherberg/Munich, Germany
| | - Christiane Hitz
- German Research Center for Environmental Health, Institute of Developmental Genetics, Helmholtz Zentrum München, Neuherberg/Munich, Germany
| | - Sabine M. Hölter
- German Research Center for Environmental Health, Institute of Developmental Genetics, Helmholtz Zentrum München, Neuherberg/Munich, Germany
| | - Dietrich Trümbach
- German Research Center for Environmental Health, Institute of Developmental Genetics, Helmholtz Zentrum München, Neuherberg/Munich, Germany
| | - Jens Hansen
- German Research Center for Environmental Health, Institute of Developmental Genetics, Helmholtz Zentrum München, Neuherberg/Munich, Germany
| | - Peter Weber
- Molecular Neurogenetics, Max-Planck-Institute of Psychiatry, Munich, Germany
| | - Benno Pütz
- Molecular Neurogenetics, Max-Planck-Institute of Psychiatry, Munich, Germany
| | - Jan M. Deussing
- Molecular Neurogenetics, Max-Planck-Institute of Psychiatry, Munich, Germany
| | - Martin Hrabé de Angelis
- Institute of Experimental Genetics, German Research Center for Environmental Health, Helmholtz Zentrum München, GmbH, Neuherberg/Munich, Germany
| | - Till Roenneberg
- Institute of Medical Psychology, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Fang Zheng
- Institute of Physiology and Pathophysiology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Christian Alzheimer
- Institute of Physiology and Pathophysiology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Alcino Silva
- Department of Neurobiology, University of California Los Angeles, Los Angeles, United States of America
| | - Wolfgang Wurst
- German Research Center for Environmental Health, Institute of Developmental Genetics, Helmholtz Zentrum München, Neuherberg/Munich, Germany
- Molecular Neurogenetics, Max-Planck-Institute of Psychiatry, Munich, Germany
- Lehrstuhl für Entwicklungsgenetik, Technical University München-Weihenstephan, Neuherberg/Munich, Germany
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V. (DZNE) Site Munich, München, Germany
| | - Ralf Kühn
- German Research Center for Environmental Health, Institute of Developmental Genetics, Helmholtz Zentrum München, Neuherberg/Munich, Germany
- Lehrstuhl für Entwicklungsgenetik, Technical University München-Weihenstephan, Neuherberg/Munich, Germany
- * E-mail:
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156
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Abe Y, Aoki Y, Kuriyama S, Kawame H, Okamoto N, Kurosawa K, Ohashi H, Mizuno S, Ogata T, Kure S, Niihori T, Matsubara Y. Prevalence and clinical features of Costello syndrome and cardio-facio-cutaneous syndrome in Japan: findings from a nationwide epidemiological survey. Am J Med Genet A 2012; 158A:1083-94. [PMID: 22495831 DOI: 10.1002/ajmg.a.35292] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 12/26/2011] [Indexed: 11/11/2022]
Abstract
Costello syndrome and cardio-facio-cutaneous (CFC) syndrome are congenital anomaly syndromes characterized by a distinctive facial appearance, heart defects, and intellectual disability. Germline mutations in HRAS cause Costello syndrome, and mutations in KRAS, BRAF, and MAP2K1/2 (MEK1/2) cause CFC syndrome. Since the discovery of the causative genes, approximately 150 new patients with each syndrome have been reported. However, the clinico-epidemiological features of these disorders remain to be identified. In order to assess the prevalence, natural history, prognosis, and tumor incidence associated with these diseases, we conducted a nationwide prevalence study of patients with Costello and CFC syndromes in Japan. Based on the result of our survey, we estimated a total number of patients with either Costello syndrome or CFC syndrome in Japan of 99 (95% confidence interval, 77-120) and 157 (95% confidence interval, 86-229), respectively. The prevalences of Costello and CFC syndromes are estimated to be 1 in 1,290,000 and 1 in 810,000 individuals, respectively. An evaluation of 15 adult patients 18-32 years of age revealed that 12 had moderate to severe intellectual disability and most live at home without constant medical care. These results suggested that the number of adult patients is likely underestimated and our results represent a minimum prevalence. This is the first epidemiological study of Costello syndrome and CFC syndrome. Identifying patients older than 32 years of age and following up on the patients reported here is important to estimate the precise prevalence and the natural history of these disorders.
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Affiliation(s)
- Yu Abe
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan
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157
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Paternal age effect mutations and selfish spermatogonial selection: causes and consequences for human disease. Am J Hum Genet 2012; 90:175-200. [PMID: 22325359 DOI: 10.1016/j.ajhg.2011.12.017] [Citation(s) in RCA: 247] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 12/05/2011] [Accepted: 12/26/2011] [Indexed: 12/25/2022] Open
Abstract
Advanced paternal age has been associated with an increased risk for spontaneous congenital disorders and common complex diseases (such as some cancers, schizophrenia, and autism), but the mechanisms that mediate this effect have been poorly understood. A small group of disorders, including Apert syndrome (caused by FGFR2 mutations), achondroplasia, and thanatophoric dysplasia (FGFR3), and Costello syndrome (HRAS), which we collectively term "paternal age effect" (PAE) disorders, provides a good model to study the biological and molecular basis of this phenomenon. Recent evidence from direct quantification of PAE mutations in sperm and testes suggests that the common factor in the paternal age effect lies in the dysregulation of spermatogonial cell behavior, an effect mediated molecularly through the growth factor receptor-RAS signal transduction pathway. The data show that PAE mutations, although arising rarely, are positively selected and expand clonally in normal testes through a process akin to oncogenesis. This clonal expansion, which is likely to take place in the testes of all men, leads to the relative enrichment of mutant sperm over time-explaining the observed paternal age effect associated with these disorders-and in rare cases to the formation of testicular tumors. As regulation of RAS and other mediators of cellular proliferation and survival is important in many different biological contexts, for example during tumorigenesis, organ homeostasis and neurogenesis, the consequences of selfish mutations that hijack this process within the testis are likely to extend far beyond congenital skeletal disorders to include complex diseases, such as neurocognitive disorders and cancer predisposition.
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158
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Pauli S, Steinemann D, Dittmann K, Wienands J, Shoukier M, Möschner M, Burfeind P, Manukjan G, Göhring G, Escherich G. Occurrence of acute lymphoblastic leukemia and juvenile myelomonocytic leukemia in a patient with Noonan syndrome carrying the germline PTPN11 mutation p.E139D. Am J Med Genet A 2012; 158A:652-8. [DOI: 10.1002/ajmg.a.34439] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 11/02/2011] [Indexed: 11/07/2022]
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159
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Razzaque MA, Komoike Y, Nishizawa T, Inai K, Furutani M, Higashinakagawa T, Matsuoka R. Characterization of a novel KRAS mutation identified in Noonan syndrome. Am J Med Genet A 2012; 158A:524-32. [PMID: 22302539 DOI: 10.1002/ajmg.a.34419] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Accepted: 10/02/2011] [Indexed: 12/31/2022]
Abstract
Noonan syndrome (NS) is the most common non-chromosomal syndrome seen in children and is characterized by short stature, dysmorphic facial features, chest deformity, a wide range of congenital heart defects and developmental delay of variable degree. Mutations in the Ras/mitogen-activated protein kinase (MAPK) signaling pathways cause about 70% of NS cases with a KRAS mutation present in about 2%. In a cohort of 65 clinically confirmed NS patients of Japanese origin, we screened for mutations in the RAS genes by direct sequencing. We found a novel mutation in KRAS with an amino acid substitution of asparagine to serine at codon 116 (N116S). We analyzed the biological activity of this mutant by ectopic expression of wild-type or mutant KRAS. NS-associated KRAS mutation resulted in Erk activation and active Ras-GTP levels, and exhibited mild cell proliferation. In addition, kras-targeted morpholino knocked-down zebrafish embryos caused heart and craniofacial malformations, while the expression of mutated kras resulted in maldevelopment of the heart. Our findings implicate that N116S change in KRAS is a hyperactive mutation which is a causative agent of NS through maldevelopment of the heart.
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Affiliation(s)
- Md Abdur Razzaque
- International Research and Educational Institute for Integrated Medical Sciences (IREIIMS), Tokyo Women's Medical University, Tokyo, Japan
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160
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Abstract
Copper (Cu) is essential for development and proliferation, yet the cellular requirements for Cu in these processes are not well defined. We report that Cu plays an unanticipated role in the mitogen-activated protein (MAP) kinase pathway. Ablation of the Ctr1 high-affinity Cu transporter in flies and mouse cells, mutation of Ctr1, and Cu chelators all reduce the ability of the MAP kinase kinase Mek1 to phosphorylate the MAP kinase Erk. Moreover, mice bearing a cardiac-tissue-specific knockout of Ctr1 are deficient in Erk phosphorylation in cardiac tissue. in vitro investigations reveal that recombinant Mek1 binds two Cu atoms with high affinity and that Cu enhances Mek1 phosphorylation of Erk in a dose-dependent fashion. Coimmunoprecipitation experiments suggest that Cu is important for promoting the Mek1-Erk physical interaction that precedes the phosphorylation of Erk by Mek1. These results demonstrate a role for Ctr1 and Cu in activating a pathway well known to play a key role in normal physiology and in cancer.
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161
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Affiliation(s)
- Gerhard Kurlemann
- Neuropediatric Department, University Hospital Munster, Munster, Germany.
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162
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Kyono A, Avishai N, Ouyang Z, Landreth GE, Murakami S. FGF and ERK signaling coordinately regulate mineralization-related genes and play essential roles in osteocyte differentiation. J Bone Miner Metab 2012; 30:19-30. [PMID: 21678127 PMCID: PMC3192226 DOI: 10.1007/s00774-011-0288-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Accepted: 05/16/2011] [Indexed: 12/22/2022]
Abstract
To examine the roles of FGF and ERK MAPK signaling in osteocyte differentiation and function, we performed microarray analyses using the osteocyte cell line MLO-Y4. This experiment identified a number of mineralization-related genes that were regulated by FGF2 in an ERK MAPK-dependent manner. Real-time PCR analysis indicated that FGF2 upregulates Ank, Enpp1, Mgp, Slc20a1, and Dmp1 in MLO-Y4 cells. Consistent with this observation, the selective FGF receptor inhibitor PD173074 decreased Ank, Enpp1, Slc20a1, and Dmp1 mRNA expression in mouse calvaria in organ culture. Since Dmp1 plays a central role in osteocyte differentiation and mineral homeostasis, we further analyzed FGF regulation of Dmp1. Similar to FGF2, FGF23 upregulated Dmp1 expression in MLO-Y4 cells in the presence of Klotho. Furthermore, increased extracellular phosphate levels partially inhibited FGF2-induced upregulation of Dmp1 mRNA expression, suggesting a coordinated regulation of Dmp1 expression by FGF signaling and extracellular phosphate. In MLO-Y4 osteocytes and in MC3T3E1 and primary calvaria osteoblasts, U0126 strongly inhibited both basal expression of Dmp1 mRNA and FGF2-induced upregulation. Consistent with the in vitro observations, real-time PCR and immunohistochemical analysis showed a strong decrease in Dmp1 expression in the skeletal elements of ERK1(-/-); ERK2(flox/flox); Prx1-Cre mice. Furthermore, scanning electron microscopic analysis revealed that no osteocytes with characteristic dendritic processes develop in the limbs of ERK1(-/-); ERK2 (flox/flox); Prx1-Cre mice. Collectively, our observations indicate that FGF signaling coordinately regulates mineralization-related genes in the osteoblast lineage and that ERK signaling is essential for Dmp1 expression and osteocyte differentiation.
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Affiliation(s)
- Ai Kyono
- Department of Orthopaedics, Case Western Reserve University, Cleveland, Ohio 44106
| | - Nanthawan Avishai
- Swagelok Center for Surface Analysis of Materials, Case School of Engineering, Case Western Reserve University, Cleveland, Ohio 44106
| | - Zhufeng Ouyang
- Department of Orthopaedics, Case Western Reserve University, Cleveland, Ohio 44106
| | - Gary E. Landreth
- Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio 44106
| | - Shunichi Murakami
- Department of Orthopaedics, Case Western Reserve University, Cleveland, Ohio 44106
- Department of Genetics, Case Western Reserve University, Cleveland, Ohio 44106
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163
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Yu S, Graf WD. BRAF gene deletion broadens the clinical spectrum neuro-cardio-facial-cutaneous syndromes. J Child Neurol 2011; 26:1593-6. [PMID: 21862832 DOI: 10.1177/0883073811413830] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Point mutations in the human BRAF gene are associated with a group of heterogeneous autosomal dominant neuro-cardio-facial-cutaneous syndromes. We identified a novel 93 kb intragenic deletion of the BRAF gene in a boy with severe developmental encephalopathy using microarray-based comparative genomic hybridization. The unique genotype and phenotype in this patient expands the spectrum of BRAF-related neurodevelopmental disorders. We propose a BRAF gene loss-of-function mechanism to best explain the biological basis of this severe developmental encephalopathy with postnatal growth deficiency.
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Affiliation(s)
- Shihui Yu
- Department of Pathology, University of Missouri-Kansas City School of Medicine, Kansas City, Missouri, USA
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164
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Lee BH, Kim JM, Jin HY, Kim GH, Choi JH, Yoo HW. Spectrum of mutations in Noonan syndrome and their correlation with phenotypes. J Pediatr 2011; 159:1029-35. [PMID: 21784453 DOI: 10.1016/j.jpeds.2011.05.024] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Revised: 03/23/2011] [Accepted: 05/16/2011] [Indexed: 10/18/2022]
Abstract
OBJECTIVES To investigate mutation spectrums and their correlations to phenotypes in Noonan syndrome (NS) and NS-related disorders that share functional alterations of the Ras-mitogen-activated protein kinase pathway. STUDY DESIGN Clinical characteristics and genotypes of 10 previously known and 2 candidate genes, SPRY1-4 and SPRED1, were investigated in 59 patients with NS, 17 with cardiofaciocutaneous syndrome, 5 with Costello syndrome, and 2 with LEOPARD syndrome. RESULTS PTPN11 (39.0%), SOS1 (20.3%), RAF1 (6.8%), KRAS (5.1%), and BRAF (1.7%) mutations were identified in NS; BRAF (41.2%), SHOC2 (23.5%), and MEK1 (5.9%) mutations in cardiofaciocutaneous syndrome; and HRAS and PTPN11 mutations in Costello syndrome and LEOPARD syndrome, respectively. No additional mutations were identified in 28.9% of NS and 35.3% of cardiofaciocutaneous syndrome. Functional characterizations of 2 RAF1 novel variants, p.P261T and p.S259T, and one SOS1 variant, p.K170E, showed enhanced activity of Ras-mitogen-activated protein kinase pathway. Normal stature was frequent in SOS1 mutations, hypertrophic cardiomyopathy in RAF1, and developmental delay in RAF1, BRAF, or SHOC2 mutations. CONCLUSIONS By identifying genotype-phenotype correlations, our study highlights the role of molecular genetic testing in the process of differential diagnosis of NS and NS-related disorders. Pathophysiologies that underlie these correlations are needed to be investigated in terms of their effects on Ras-mitogen-activated protein kinase pathway.
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Affiliation(s)
- Beom Hee Lee
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
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165
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Abstract
Cardiofaciocutaneous (CFC) syndrome is a multiple congenital anomaly/mental retardation syndrome characterized by a distinctive facial appearance, ectodermal abnormalities, and heart defects. Clinically, it overlaps with both Noonan syndrome and Costello syndrome. Mutations in KRAS, BRAF, and MAP2K1/2 (MEK1/2) have been identified in patients with CFC syndrome. BRAF mutations are involved in more than 80% of CFC syndrome patients, and we have reported earlier that 2 CFC patients with BRAF mutations developed acute lymphoblastic leukemia. Here we report a boy with CFC syndrome who developed non-Hodgkin lymphoma. At 2 months of age, he developed pneumonia with pleurisy and was diagnosed as having non-Hodgkin lymphoma (precursor T-cell lymphoblastic lymphoma) by cytopathologic examination of the pleural fluid. He was suspected of having Noonan syndrome because of his facial appearance, webbed neck, and cubitus valgus. Precursor T-cell lymphoblastic lymphoma was treated by the TCCSG NHL 94-04 protocol. At 9 years of age, he was clinically reevaluated and diagnosed as having CFC syndrome because of his distinctive facial appearance, multiple nevi, and moderate mental retardation. Sequencing analysis showed a germline p.A246P (c.736G>C) mutation in BRAF reported earlier in CFC syndrome. Molecular diagnosis and careful observation should be considered in children with CFC syndrome.
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166
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Fasano S, Brambilla R. Ras-ERK Signaling in Behavior: Old Questions and New Perspectives. Front Behav Neurosci 2011; 5:79. [PMID: 22131969 PMCID: PMC3223382 DOI: 10.3389/fnbeh.2011.00079] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 11/03/2011] [Indexed: 11/13/2022] Open
Abstract
The role of Ras–ERK signaling in behavioral plasticity is well established. Inhibition studies using the blood–brain barrier permeable drug SL327 have conclusively demonstrated that this neuronal cell signaling cascade is a crucial component of the synaptic machinery implicated in the formation of various forms of long-term memory, from spatial learning to fear and operant conditioning. However, abnormal Ras–ERK signaling has also been linked to a number of neuropsychiatric conditions, including mental retardation syndromes (“RASopathies”), drug addiction, and l-DOPA induced dyskinesia (LID). The work recently done on these brain disorders has pointed to previously underappreciated roles of Ras–ERK in specific subsets of neurons, like GABAergic interneurons of the hippocampus or the cortex, as well as in the medium spiny neurons of the striatum. Here we will highlight the open questions related to Ras–ERK signaling in these behavioral manifestations and propose crucial experiments for the future.
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Affiliation(s)
- Stefania Fasano
- Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute and University Milano, Italy
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167
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Abstract
Ras genes are frequently activated in cancer. Attempts to develop drugs that target mutant Ras proteins have, so far, been unsuccessful. Tumors bearing these mutations, therefore, remain among the most difficult to treat. Most efforts to block activated Ras have focused on pathways downstream. Drugs that inhibit Raf kinase have shown clinical benefit in the treatment of malignant melanoma. However, these drugs have failed to show clinical benefit in Ras mutant tumors. It remains unclear to what extent Ras depends on Raf kinase for transforming activity, even though Raf proteins bind directly to Ras and are certainly major effectors of Ras action in normal cells and in development. Furthermore, Raf kinase inhibitors can lead to paradoxical activation of the MAPK pathway. MEK inhibitors block the Ras-MAPK pathway, but often activate the PI3'-kinase, and have shown little clinical benefit as single agents. This activation is mediated by EGF-R and other receptor tyrosine kinases through relief of a negative feedback loop from ERK. Drug combinations that target multiple points within the Ras signaling network are likely to be necessary to achieve substantial clinical benefit. Other effectors may also contribute to Ras signaling and provide a source of targets. In addition, unbiased screens for genes necessary for Ras transformation have revealed new potential targets and have added to our understanding of Ras cancer biology.
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Affiliation(s)
- Stephan Gysin
- UCSF Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA, USA
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168
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Abstract
Somatic, gain-of-function mutations in ras genes were the first specific genetic alterations identified in human cancer about 3 decades ago. Studies during the last quarter century have characterized the Ras proteins as essential components of signaling networks controlling cellular proliferation, differentiation, or survival. The oncogenic mutations of the H-ras, N-ras, or K-ras genes frequently found in human tumors are known to throw off balance the normal outcome of those signaling pathways, thus leading to tumor development. Oncogenic mutations in a number of other upstream or downstream components of Ras signaling pathways (including membrane RTKs or cytosolic kinases) have been detected more recently in association with a variety of cancers. Interestingly, the oncogenic Ras mutations and the mutations in other components of Ras/MAPK signaling pathways appear to be mutually exclusive events in most tumors, indicating that deregulation of Ras-dependent signaling is the essential requirement for tumorigenesis. In contrast to sporadic tumors, separate studies have identified germline mutations in Ras and various other components of Ras signaling pathways that occur in specific association with a number of different familial, developmental syndromes frequently sharing common phenotypic cardiofaciocutaneous features. Finally, even without being a causative force, defective Ras signaling has been cited as a contributing factor to many other human illnesses, including diabetes and immunological and inflammatory disorders. We aim this review at summarizing and updating current knowledge on the contribution of Ras mutations and altered Ras signaling to development of various tumoral and nontumoral pathologies.
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169
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Taglieri DM, Monasky MM, Knezevic I, Sheehan KA, Lei M, Wang X, Chernoff J, Wolska BM, Ke Y, Solaro RJ. Ablation of p21-activated kinase-1 in mice promotes isoproterenol-induced cardiac hypertrophy in association with activation of Erk1/2 and inhibition of protein phosphatase 2A. J Mol Cell Cardiol 2011; 51:988-96. [PMID: 21971074 DOI: 10.1016/j.yjmcc.2011.09.016] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 09/09/2011] [Accepted: 09/11/2011] [Indexed: 12/16/2022]
Abstract
Earlier investigations in our lab indicated an anti-adrenergic effect induced by activation of p21-activated kinase (Pak-1) and protein phosphatase 2A (PP2A). Our objective was to test the hypothesis that Pak-1/PP2A is a signaling cascade controlling stress-induced cardiac growth. We determined the effects of ablation of the Pak-1 gene on the response of the myocardium to chronic stress of isoproterenol (ISO) administration. Wild-type (WT) and Pak-1-knockout (Pak-1-KO) mice were randomized into six groups to receive either ISO, saline (CTRL), or ISO and FR180204, a selective inhibitor of Erk1/2. Echocardiography revealed that hearts of the Pak-1-KO/ISO group had increased LV fractional shortening, reduced LV chamber volume in diastole and systole, increased cardiac hypertrophy, and enhanced transmitral early filling deceleration time, compared to all other groups. The changes were associated with an increase in relative Erk1/2 activation in Pak-1-KO/ISO mice versus all other groups. ISO-induced cardiac hypertrophy and Erk1/2 activation in Pak-1-KO/ISO were attenuated when the selective Erk1/2 inhibitor FR180204 was administered. Immunoprecipitation showed an association between Pak-1, PP2A, and Erk1/2. Cardiac myocytes infected with an adenoviral vector expressing constitutively active Pak-1 showed a repression of Erk1/2 activation. p38 MAPK phosphorylation was decreased in Pak-1-KO/ISO and Pak-1-KO/CTRL mice compared to WT. Levels of phosphorylated PP2A were increased in ISO-treated Pak-1-KO mice, indicating reduced phosphatase activity. Maximum Ca(2+)-activated tension in detergent-extracted bundles of papillary fibers from ISO-treated Pak-1-KO mice was higher than in all other groups. Analysis of cTnI phosphorylation indicated that compared to WT, ISO-induced phosphorylation of cTnI was blunted in Pak-1-KO mice. Active Pak-1 is a natural inhibitor of Erk1/2 and a novel anti-hypertrophic signaling molecule upstream of PP2A.
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Affiliation(s)
- Domenico M Taglieri
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, 835 S. Wolcott Ave, M/C 901, Chicago, IL 60612-7342, USA.
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170
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He Y, Staser K, Rhodes SD, Liu Y, Wu X, Park SJ, Yuan J, Yang X, Li X, Jiang L, Chen S, Yang FC. Erk1 positively regulates osteoclast differentiation and bone resorptive activity. PLoS One 2011; 6:e24780. [PMID: 21961044 PMCID: PMC3178550 DOI: 10.1371/journal.pone.0024780] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 08/17/2011] [Indexed: 01/02/2023] Open
Abstract
The extracellular signal-regulated kinases (ERK1 and 2) are widely-expressed and they modulate proliferation, survival, differentiation, and protein synthesis in multiple cell lineages. Altered ERK1/2 signaling is found in several genetic diseases with skeletal phenotypes, including Noonan syndrome, Neurofibromatosis type 1, and Cardio-facio-cutaneous syndrome, suggesting that MEK-ERK signals regulate human skeletal development. Here, we examine the consequence of Erk1 and Erk2 disruption in multiple functions of osteoclasts, specialized macrophage/monocyte lineage-derived cells that resorb bone. We demonstrate that Erk1 positively regulates osteoclast development and bone resorptive activity, as genetic disruption of Erk1 reduced osteoclast progenitor cell numbers, compromised pit formation, and diminished M-CSF-mediated adhesion and migration. Moreover, WT mice reconstituted long-term with Erk1−/− bone marrow mononuclear cells (BMMNCs) demonstrated increased bone mineral density as compared to recipients transplanted with WT and Erk2−/− BMMNCs, implicating marrow autonomous, Erk1-dependent osteoclast function. These data demonstrate Erk1 plays an important role in osteoclast functions while providing rationale for the development of Erk1-specific inhibitors for experimental investigation and/or therapeutic modulation of aberrant osteoclast function.
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Affiliation(s)
- Yongzheng He
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Karl Staser
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Steven D. Rhodes
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Yaling Liu
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Xiaohua Wu
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Su-Jung Park
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Jin Yuan
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Xianlin Yang
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Xiaohong Li
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Li Jiang
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Shi Chen
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Feng-Chun Yang
- Departments of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- * E-mail:
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171
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Xu D, Liu X, Yu WM, Meyerson HJ, Guo C, Gerson SL, Qu CK. Non-lineage/stage-restricted effects of a gain-of-function mutation in tyrosine phosphatase Ptpn11 (Shp2) on malignant transformation of hematopoietic cells. ACTA ACUST UNITED AC 2011; 208:1977-88. [PMID: 21930766 PMCID: PMC3182060 DOI: 10.1084/jem.20110450] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A common Shp2 mutation leads to myeloproliferative disease and malignant acute leukemia in stem cells and committed progenitors, associated with Shp2 maintaining chromosomal stability Activating mutations in protein tyrosine phosphatase 11 (Ptpn11) have been identified in childhood acute leukemias, in addition to juvenile myelomonocytic leukemia (JMML), which is a myeloproliferative disorder (MPD). It is not clear whether activating mutations of this phosphatase play a causal role in the pathogenesis of acute leukemias. If so, the cell origin of leukemia-initiating stem cells (LSCs) remains to be determined. Ptpn11E76K mutation is the most common and most active Ptpn11 mutation found in JMML and acute leukemias. However, the pathogenic effects of this mutation have not been well characterized. We have created Ptpn11E76K conditional knock-in mice. Global Ptpn11E76K/+ mutation results in early embryonic lethality. Induced knock-in of this mutation in pan hematopoietic cells leads to MPD as a result of aberrant activation of hematopoietic stem cells (HSCs) and myeloid progenitors. These animals subsequently progress to acute leukemias. Intriguingly, in addition to acute myeloid leukemia (AML), T cell acute lymphoblastic leukemia/lymphoma (T-ALL) and B-ALL are evolved. Moreover, tissue-specific knock-in of Ptpn11E76K/+ mutation in lineage-committed myeloid, T lymphoid, and B lymphoid progenitors also results in AML, T-ALL, and B-ALL, respectively. Further analyses have revealed that Shp2 (encoded by Ptpn11) is distributed to centrosomes and that Ptpn11E76K/+ mutation promotes LSC development, partly by causing centrosome amplification and genomic instability. Thus, Ptpn11E76K mutation has non–lineage-specific effects on malignant transformation of hematopoietic cells and initiates acute leukemias at various stages of hematopoiesis.
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Affiliation(s)
- Dan Xu
- Department of Medicine, Division of Hematology and Oncology, Center for Stem Cell and Regenerative Medicine, Case Comprehensive Cancer Center, and Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
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172
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Takahashi A, Tsutsumi R, Kikuchi I, Obuse C, Saito Y, Seidi A, Karisch R, Fernandez M, Cho T, Ohnishi N, Rozenblatt-Rosen O, Meyerson M, Neel BG, Hatakeyama M. SHP2 tyrosine phosphatase converts parafibromin/Cdc73 from a tumor suppressor to an oncogenic driver. Mol Cell 2011; 43:45-56. [PMID: 21726809 DOI: 10.1016/j.molcel.2011.05.014] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 03/04/2011] [Accepted: 05/08/2011] [Indexed: 12/11/2022]
Abstract
Deregulation of SHP2 is associated with malignant diseases as well as developmental disorders. Although SHP2 is required for full activation of RAS signaling, other potential roles in cell physiology have not been elucidated. Here we show that SHP2 dephosphorylates parafibromin/Cdc73, a core component of the RNA polymerase II-associated factor (PAF) complex. Parafibromin is known to act as a tumor suppressor that inhibits cyclin D1 and c-myc by recruiting SUV39H1 histone methyltransferase. However, parafibromin can also act in the opposing direction by binding β-catenin, thereby activating promitogenic/oncogenic Wnt signaling. We found that, on tyrosine dephosphorylation by SHP2, parafibromin acquires the ability to stably bind β-catenin. The parafibromin/β-catenin interaction overrides parafibromin/SUV39H1-mediated transrepression and induces expression of Wnt target genes, including cyclin D1 and c-myc. Hence, SHP2 governs the opposing functions of parafibromin, deregulation of which may cause the development of tumors or developmental malformations.
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Affiliation(s)
- Atsushi Takahashi
- Division of Microbiology, Graduate School of Medicine, University of Tokyo, Tokyo 113-0033, Japan
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173
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Epilepsy in RAS/MAPK syndrome: two cases of cardio-facio-cutaneous syndrome with epileptic encephalopathy and a literature review. Seizure 2011; 21:55-60. [PMID: 21871821 DOI: 10.1016/j.seizure.2011.07.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Accepted: 07/29/2011] [Indexed: 11/21/2022] Open
Abstract
We report two individual cases of cardio-facio-cutaneous (CFC) syndrome with severe neurological impairment consisting of infantile spasms with hypsarrhythmia and refractory epilepsy with multifocal epileptic paroxysms such as modified hypsarrhythmia. Both cases shared diffuse brain atrophy and severely delayed myelination on neuroimaging. Genetic analysis revealed individual heterozygous mutations in the KRAS (phenotype of CFC/Noonan syndrome) and BRAF genes (phenotype of CFC syndrome). Neurological impairment in cases with mutations in the RAS/MAPK (mitogen activated protein kinase) signal pathway may be more severe, and could be linked to some forms of refractory epilepsy, especially epileptic encephalopathy that includes infantile spasms.
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174
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Niihori T, Aoki Y, Okamoto N, Kurosawa K, Ohashi H, Mizuno S, Kawame H, Inazawa J, Ohura T, Arai H, Nabatame S, Kikuchi K, Kuroki Y, Miura M, Tanaka T, Ohtake A, Omori I, Ihara K, Mabe H, Watanabe K, Niijima S, Okano E, Numabe H, Matsubara Y. HRAS mutants identified in Costello syndrome patients can induce cellular senescence: possible implications for the pathogenesis of Costello syndrome. J Hum Genet 2011; 56:707-15. [PMID: 21850009 DOI: 10.1038/jhg.2011.85] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Costello syndrome (CS) is a congenital disease that is characterized by a distinctive facial appearance, failure to thrive, mental retardation and cardiomyopathy. In 2005, we discovered that heterozygous germline mutations in HRAS caused CS. Several studies have shown that CS-associated HRAS mutations are clustered in codons 12 and 13, and mutations in other codons have also been identified. However, a comprehensive comparison of the substitutions identified in patients with CS has not been conducted. In the current study, we identified four mutations (p.G12S, p.G12A, p.G12C and p.G12D) in 21 patients and analyzed the associated clinical manifestations of CS in these individuals. To examine functional differences among the identified mutations, we characterized a total of nine HRAS mutants, including seven distinct substitutions in codons 12 and 13, p.K117R and p.A146T. The p.A146T mutant demonstrated the weakest Raf-binding activity, and the p.K117R and p.A146T mutants had weaker effects on downstream c-Jun N-terminal kinase signaling than did codon 12 or 13 mutants. We demonstrated that these mutant HRAS proteins induced senescence when overexpressed in human fibroblasts. Oncogene-induced senescence is a cellular reaction that controls cell proliferation in response to oncogenic mutation and it has been considered one of the tumor suppression mechanisms in vivo. Our findings suggest that the HRAS mutations identified in CS are sufficient to cause oncogene-induced senescence and that cellular senescence might therefore contribute to the pathogenesis of CS.
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Affiliation(s)
- Tetsuya Niihori
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan.
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175
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Watanabe Y, Yano S, Niihori T, Aoki Y, Matsubara Y, Yoshino M, Matsuishi T. A familial case of LEOPARD syndrome associated with a high-functioning autism spectrum disorder. Brain Dev 2011; 33:576-9. [PMID: 21093184 DOI: 10.1016/j.braindev.2010.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Revised: 10/03/2010] [Accepted: 10/06/2010] [Indexed: 11/29/2022]
Abstract
A connection between LEOPARD syndrome (a rare autosomal dominant disorder) and autism spectrum disorders (ASDs) may exist. Of four related individuals (father and three sons) with LEOPARD syndrome, all patients exhibited clinical symptoms consistent with ASDs. Findings included aggressive behavior and impairment of social interaction, communication, and range of interests. The coexistence of LEOPARD syndrome and ASDs in the related individuals may be an incidental familial event or indicative that ASDs is associated with LEOPARD syndrome. There have been no other independent reports of the association of LEOPARD syndrome and ASDs. Molecular and biochemical mechanisms that may suggest a connection between LEOPARD syndrome and ASDs are discussed.
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Affiliation(s)
- Yoriko Watanabe
- Department of Pediatrics and Child Health, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Japan.
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176
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Heervä E, Peltonen S, Pirttiniemi P, Happonen RP, Visnapuu V, Peltonen J. Short mandible, maxilla and cranial base are common in patients with neurofibromatosis 1. Eur J Oral Sci 2011; 119:121-7. [PMID: 21410551 DOI: 10.1111/j.1600-0722.2011.00811.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Neurofibromatosis type 1 (NF1) is an autosomal-dominant neuro-cutaneous-skeletal syndrome. Neurofibromatosis type 1 is one of the Rasopathies, and at the cellular level NF1 results in a hyperactive Ras pathway. In the current investigation, our aim was to study lateral skull X-rays (cephalograms) to assess NF1-related craniofacial morphology. A total of 85 Finnish patients with NF1, including four patients with plexiform neurofibroma of the 5th cranial nerve, and their age- and gender-matched controls, were enrolled in the study. The results showed that patients with NF1 typically had a short mandible, maxilla, and cranial base compared with healthy controls, irrespective of age, but the results were statistically significant only in adults. The length of the mandible, the maxilla and the cranial base correlated with the height of patients under 19 yr of age, but this correlation was absent in adult patients. Thus, a tall adult patient with NF1 may have short jaws and a short cranial base. In conclusion, the NF1 gene apparently influences the growth of craniofacial bones, thus contributing to the craniofacial morphology in NF1.
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Affiliation(s)
- Eetu Heervä
- Department of Cell Biology and Anatomy, University of Turku, Kiinamyllynkatu, Finland
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177
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Richards AA, Garg V. Genetics of congenital heart disease. Curr Cardiol Rev 2011; 6:91-7. [PMID: 21532774 PMCID: PMC2892081 DOI: 10.2174/157340310791162703] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Revised: 10/24/2009] [Accepted: 10/28/2009] [Indexed: 12/21/2022] Open
Abstract
Cardiovascular malformations are the most common type of birth defect and result in significant mortality worldwide. The etiology for the majority of these anomalies remains unknown but genetic factors are being recognized as playing an increasingly important role. Advances in our molecular understanding of normal heart development have led to the identification of numerous genes necessary for cardiac morphogenesis. This work has aided the discovery of an increasing number of monogenic causes of human cardiovascular malformations. More recently, studies have identified single nucleotide polymorphisms and submicroscopic copy number abnormalities as having a role in the pathogenesis of congenital heart disease. This review discusses these discoveries and summarizes our increasing understanding of the genetic basis of congenital heart disease.
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Affiliation(s)
- Ashleigh A Richards
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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178
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Hernández-Martín A, Torrelo A. Rasopathies: Developmental Disorders That Predispose to Cancer and Skin Manifestations. ACTAS DERMO-SIFILIOGRAFICAS 2011. [DOI: 10.1016/j.adengl.2011.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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179
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Hernández-Martín A, Torrelo A. Rasopatías: trastornos del desarrollo con predisposición al cáncer y manifestaciones cutáneas. ACTAS DERMO-SIFILIOGRAFICAS 2011; 102:402-16. [DOI: 10.1016/j.ad.2011.02.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 02/23/2011] [Accepted: 02/28/2011] [Indexed: 12/30/2022] Open
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180
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Sacco E, Metalli D, Spinelli M, Manzoni R, Samalikova M, Grandori R, Morrione A, Traversa S, Alberghina L, Vanoni M. Novel RasGRF1-derived Tat-fused peptides inhibiting Ras-dependent proliferation and migration in mouse and human cancer cells. Biotechnol Adv 2011; 30:233-43. [PMID: 21620943 DOI: 10.1016/j.biotechadv.2011.05.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Accepted: 05/09/2011] [Indexed: 10/18/2022]
Abstract
Mutations of RAS genes are critical events in the pathogenesis of different human tumors and Ras proteins represent a major clinical target for the development of specific inhibitors to use as anticancer agents. Here we present RasGRF1-derived peptides displaying both in vitro and in vivo Ras inhibitory properties. These peptides were designed on the basis of the down-sizing of dominant negative full-length RasGRF1 mutants. The over-expression of these peptides can revert the phenotype of K-RAS transformed mouse fibroblasts to wild type, as monitored by several independent biological readouts, including Ras-GTP intracellular levels, ERK activity, morphology, proliferative potential and anchorage independent growth. Fusion of the RasGRF1-derived peptides with the Tat protein transduction domain allows their uptake into mammalian cells. Chemically synthesized Tat-fused peptides, reduced to as small as 30 residues on the basis of structural constraints, retain Ras inhibitory activity. These small peptides interfere in vitro with the GEF catalyzed nucleotide dissociation and exchange on Ras, reduce cell proliferation of K-RAS transformed mouse fibroblasts, and strongly reduce Ras-dependent IGF-I-induced migration and invasion of human bladder cancer cells. These results support the use of RasGRF1-derived peptides as model compounds for the development of Ras inhibitory anticancer agents.
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Affiliation(s)
- Elena Sacco
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, Italy.
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181
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Prada CE, Zarate YA, Hagenbuch S, Lovell A, Schorry EK, Hopkin RJ. Lethal presentation of neurofibromatosis and Noonan syndrome. Am J Med Genet A 2011; 155A:1360-6. [PMID: 21567923 DOI: 10.1002/ajmg.a.33996] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Accepted: 02/20/2011] [Indexed: 11/09/2022]
Abstract
Neurofibromatosis type 1 and Noonan syndrome are both common genetic disorders with autosomal dominant inheritance. Similarities between neurofibromatosis type 1 and Noonan syndrome have been noted for over 20 years and patients who share symptoms of both conditions are often given the diagnosis of neurofibromatosis-Noonan syndrome (NFNS). The molecular basis of these combined phenotypes was poorly understood and controversially discussed over several decades until the discovery that the syndromes are related through disturbances of the Ras pathway. We present an infant male with coarse facial features, severe supravalvar pulmonic stenosis, automated atrial tachycardia, hypertrophic cardiomyopathy, airway compression, severe neurological involvement, and multiple complications that lead to death during early infancy. The severity of clinical presentation and significant dysmorphic features suggested the possibility of a double genetic disorder in the Ras pathway instead of NFNS. Molecular analysis showed a missense mutation in exon 25 of the NF1 gene (4288A>G, p.N1430D) and a pathogenic mutation on exon 8 (922A>G, p.N308D) of the PTPN11 gene. Cardiovascular disease has been well described in patients with Noonan syndrome with PTPN11 mutations but the role of haploinsufficiency for neurofibromin in the heart development and function is not yet well understood. Our case suggests that a double genetic defect resulting in the hypersignaling of the Ras pathway may lead to complex cardiovascular abnormalities, cardiomyopathy, refractory arrhythmia, severe neurological phenotype, and early death.
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Affiliation(s)
- Carlos E Prada
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Ohio 45229, USA
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182
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Del Re DP, Sadoshima J. Is Raf1 a nexus for cardiac hypertrophic signaling in human disease? J Mol Cell Cardiol 2011; 51:1-3. [PMID: 21539844 DOI: 10.1016/j.yjmcc.2011.04.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Accepted: 04/14/2011] [Indexed: 01/20/2023]
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183
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Lepri F, De Luca A, Stella L, Rossi C, Baldassarre G, Pantaleoni F, Cordeddu V, Williams BJ, Dentici ML, Caputo V, Venanzi S, Bonaguro M, Kavamura I, Faienza MF, Pilotta A, Stanzial F, Faravelli F, Gabrielli O, Marino B, Neri G, Silengo MC, Ferrero GB, Torrrente I, Selicorni A, Mazzanti L, Digilio MC, Zampino G, Dallapiccola B, Gelb BD, Tartaglia M. SOS1 mutations in Noonan syndrome: molecular spectrum, structural insights on pathogenic effects, and genotype-phenotype correlations. Hum Mutat 2011; 32:760-72. [PMID: 21387466 PMCID: PMC3118925 DOI: 10.1002/humu.21492] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 02/23/2011] [Indexed: 01/03/2023]
Abstract
Noonan syndrome (NS) is among the most common nonchromosomal disorders affecting development and growth. NS is caused by aberrant RAS-MAPK signaling and is genetically heterogeneous, which explains, in part, the marked clinical variability documented for this Mendelian trait. Recently, we and others identified SOS1 as a major gene underlying NS. Here, we explored further the spectrum of SOS1 mutations and their associated phenotypic features. Mutation scanning of the entire SOS1 coding sequence allowed the identification of 33 different variants deemed to be of pathological significance, including 16 novel missense changes and in-frame indels. Various mutation clusters destabilizing or altering orientation of regions of the protein predicted to contribute structurally to the maintenance of autoinhibition were identified. Two previously unappreciated clusters predicted to enhance SOS1's recruitment to the plasma membrane, thus promoting a spatial reorientation of domains contributing to inhibition, were also recognized. Genotype–phenotype analysis confirmed our previous observations, establishing a high frequency of ectodermal anomalies and a low prevalence of cognitive impairment and reduced growth. Finally, mutation analysis performed on cohorts of individuals with nonsyndromic pulmonic stenosis, atrial septal defects, and ventricular septal defects excluded a major contribution of germline SOS1 lesions to the isolated occurrence of these cardiac anomalies. Hum Mutat 32:760–772, 2011. © 2011 Wiley-Liss, Inc.
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Affiliation(s)
- Francesca Lepri
- IRCCS Casa Sollievo della Sofferenza, Laboratorio Mendel, San Giovanni Rotondo, Italy
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184
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Magee J, Cygler M. Interactions between kinase scaffold MP1/p14 and its endosomal anchoring protein p18. Biochemistry 2011; 50:3696-705. [PMID: 21452851 DOI: 10.1021/bi101972y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Scaffold and adaptor proteins provide means for the spatial organization of signaling cascades. MP1 is a scaffold protein in the RAF/MEK/ERK pathway and together with p14 forms a heterodimer that was shown to be responsible for localization of MEK to the late endosomal compartment. However, the mechanism by which MP1/p14 tethers MEK to the endosomal membrane was not resolved. Recently, an adaptor protein p18 was identified as a binding partner of MP1/p14. p18 is attached to the endosomal surface by myristoyl and palmitoyl groups located at the N-terminus of the protein and tethers the signaling complex to the cytoplasmic surface of late endosomes. p18 expressed in E. coli is retained in inclusion bodies, and we developed a protocol to refold it from the denatured state. Coexpression of p18 with MP1/p14 leads to a soluble protein complex. We examined the interaction of p18 with the MP1/p14 constitutive heterodimer. We cloned various constructs of p18 and characterized their behavior and interactions with MP1/p14 in vitro using SEC and pull-down assays. We determined that the refolded p18 is a monomer in solution with molten globule characteristics. Its binding to MP1/p14 promotes folding and ordering. We also identified a proteolytically stable fragment of p18 and showed that it binds to MP1/p14 with similar affinity to the full-length construct and determined an apparent dissociation constant in the low micromolar range for the interaction. Finally, we show that the ∼60 C-terminal residues of p18 are not required for in vitro interaction with MP1/p14 heterodimer, in contrast to previously reported findings showing that truncation of 41 C-terminal residues of p18 prevents endosomal localization of MP1/p14.
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Affiliation(s)
- James Magee
- Biotechnology Research Institute, NRCC, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2, Canada
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185
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Viskochil DH. Disorders of the ras pathway: an introduction. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2011; 157C:79-82. [PMID: 21495180 DOI: 10.1002/ajmg.c.30301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- David H Viskochil
- Division of Medical Genetics, Department of Pediatrics, School of Medicine, University of Utah, 2C412, 50 Mario Capecchi Drive, Salt Lake City, UT 84132, USA.
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186
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Jongmans MCJ, van der Burgt I, Hoogerbrugge PM, Noordam K, Yntema HG, Nillesen WM, Kuiper RP, Ligtenberg MJL, van Kessel AG, van Krieken JHJM, Kiemeney LALM, Hoogerbrugge N. Cancer risk in patients with Noonan syndrome carrying a PTPN11 mutation. Eur J Hum Genet 2011; 19:870-4. [PMID: 21407260 PMCID: PMC3172922 DOI: 10.1038/ejhg.2011.37] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Noonan syndrome (NS) is characterized by short stature, facial dysmorphisms and congenital heart defects. PTPN11 mutations are the most common cause of NS. Patients with NS have a predisposition for leukemia and certain solid tumors. Data on the incidence of malignancies in NS are lacking. Our objective was to estimate the cancer risk and spectrum in patients with NS carrying a PTPN11 mutation. In addition, we have investigated whether specific PTPN11 mutations result in an increased malignancy risk. We have performed a cohort study among 297 Dutch NS patients with a PTPN11 mutation (mean age 18 years). The cancer histories were collected from the referral forms for DNA diagnostics, and by consulting the Dutch national registry of pathology and the Netherlands Cancer Registry. The reported frequencies of cancer among NS patients were compared with the expected frequencies using population-based incidence rates. In total, 12 patients with NS developed a malignancy, providing a cumulative risk for developing cancer of 23% (95% confidence interval (CI), 8–38%) up to age 55 years, which represents a 3.5-fold (95% CI, 2.0–5.9) increased risk compared with that in the general population. Hematological malignancies occurred most frequently. Two malignancies, not previously observed in NS, were found: a malignant mastocytosis and malignant epithelioid angiosarcoma. No correlation was found between specific PTPN11 mutations and cancer occurrence. In conclusion, this study provides first evidence of an increased risk of cancer in patients with NS and a PTPN11 mutation, compared with that in the general population. Our data do not warrant specific cancer surveillance.
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Affiliation(s)
- Marjolijn C J Jongmans
- Department of Human Genetics, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
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187
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Abstract
Abstract
Autoimmune lymphoproliferative syndrome (ALPS) is classically defined as a disease with defective FAS-mediated apoptosis (type I-III). Germline NRAS mutation was recently identified in type IV ALPS. We report 2 cases with ALPS-like disease with somatic KRAS mutation. Both cases were characterized by prominent autoimmune cytopenia and lymphoadenopathy/splenomegaly. These patients did not satisfy the diagnostic criteria for ALPS or juvenile myelomonocytic leukemia and are probably defined as a new disease entity of RAS-associated ALPS-like disease (RALD).
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188
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Terao M, Sakai N, Higashiyama S, Kotobuki Y, Tanemura A, Wataya-Kaneda M, Yutsudo M, Ozono K, Katayama I. Cutaneous symptoms in a patient with cardiofaciocutaneous syndrome and increased ERK phosphorylation in skin fibroblasts. Br J Dermatol 2011; 163:881-4. [PMID: 20518782 DOI: 10.1111/j.1365-2133.2010.09875.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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189
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Janosi L, Gorfe AA. Segregation of negatively charged phospholipids by the polycationic and farnesylated membrane anchor of Kras. Biophys J 2011; 99:3666-74. [PMID: 21112291 DOI: 10.1016/j.bpj.2010.10.031] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Revised: 10/18/2010] [Accepted: 10/20/2010] [Indexed: 12/19/2022] Open
Abstract
The Kras protein, a member of the Ras family of bio-switches that are frequently mutated in cancer and developmental disorders, becomes functional when anchored to the inner surface of the plasma membrane. It is well known that membrane attachment involves the farnesylated and poylcationic C-terminus of the protein. However, little is known about the structure of the complex and the specific protein-lipid interactions that are responsible for the binding. On the basis of data from extensive (>0.55 μs) molecular dynamics simulations of multiple Kras anchors in bilayers of POPC/POPG lipids (4:1 ratio), we show that, as expected, Kras is tethered to the bilayer surface by specific lysine-POPG salt bridges and by nonspecific farnesyl-phospholipid van der Waals interactions. Unexpectedly, however, only the C-terminal five of the eight Kras Lys side chains were found to directly interact with the bilayer, with the N-terminal ones staying in water. Furthermore, the positively charged Kras anchors pull the negatively charged POPG lipids together, leading to the clustering of the POPG lipids around the proteins. This selective Kras-POPG interaction is directly related to the specific geometry of the backbone, which exists in two major conformational states: 1), a stable native-like ensemble of structures characterized by an extended geometry with a pseudohelical turn; and 2), less stable nonnative ensembles of conformers characterized by severely bent geometries. Finally, although the interface-bound anchor has little effect on the overall structure of the bilayer, it induces local thinning within a persistence length of ∼12 Å. Our results thus go beyond documenting how Kras attaches to a mixed bilayer of charged and neutral lipids; they highlight a fascinating process of protein-induced lipid sorting coupled with the (re)shaping of a surface-bound protein by the host lipids.
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Affiliation(s)
- Lorant Janosi
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
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190
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Matallanas D, Birtwistle M, Romano D, Zebisch A, Rauch J, von Kriegsheim A, Kolch W. Raf family kinases: old dogs have learned new tricks. Genes Cancer 2011; 2:232-60. [PMID: 21779496 PMCID: PMC3128629 DOI: 10.1177/1947601911407323] [Citation(s) in RCA: 266] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
First identified in the early 1980s as retroviral oncogenes, the Raf proteins have been the objects of intense research. The discoveries 10 years later that the Raf family members (Raf-1, B-Raf, and A-Raf) are bona fide Ras effectors and upstream activators of the ubiquitous ERK pathway increased the interest in these proteins primarily because of the central role that this cascade plays in cancer development. The important role of Raf in cancer was corroborated in 2002 with the discovery of B-Raf genetic mutations in a large number of tumors. This led to intensified drug development efforts to target Raf signaling in cancer. This work yielded not only recent clinical successes but also surprising insights into the regulation of Raf proteins by homodimerization and heterodimerization. Surprising insights also came from the hunt for new Raf targets. Although MEK remains the only widely accepted Raf substrate, new kinase-independent roles for Raf proteins have emerged. These include the regulation of apoptosis by suppressing the activity of the proapoptotic kinases, ASK1 and MST2, and the regulation of cell motility and differentiation by controlling the activity of Rok-α. In this review, we discuss the regulation of Raf proteins and their role in cancer, with special focus on the interacting proteins that modulate Raf signaling. We also describe the new pathways controlled by Raf proteins and summarize the successes and failures in the development of efficient anticancer therapies targeting Raf. Finally, we also argue for the necessity of more systemic approaches to obtain a better understanding of how the Ras-Raf signaling network generates biological specificity.
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Affiliation(s)
- David Matallanas
- Systems Biology Ireland, University College Dublin, Dublin, Ireland
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191
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Wu X, Simpson J, Hong JH, Kim KH, Thavarajah NK, Backx PH, Neel BG, Araki T. MEK-ERK pathway modulation ameliorates disease phenotypes in a mouse model of Noonan syndrome associated with the Raf1(L613V) mutation. J Clin Invest 2011; 121:1009-25. [PMID: 21339642 DOI: 10.1172/jci44929] [Citation(s) in RCA: 160] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2010] [Accepted: 12/15/2010] [Indexed: 12/30/2022] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is a leading cause of sudden death in children and young adults. Abnormalities in several signaling pathways are implicated in the pathogenesis of HCM, but the role of the RAS-RAF-MEK-ERK MAPK pathway has been controversial. Noonan syndrome (NS) is one of several autosomal-dominant conditions known as RASopathies, which are caused by mutations in different components of this pathway. Germline mutations in RAF1 (which encodes the serine-threonine kinase RAF1) account for approximately 3%-5% of cases of NS. Unlike other NS alleles, RAF1 mutations that confer increased kinase activity are highly associated with HCM. To explore the pathogenesis of such mutations, we generated knockin mice expressing the NS-associated Raf1(L613V) mutation. Like NS patients, mice heterozygous for this mutation (referred to herein as L613V/+ mice) had short stature, craniofacial dysmorphia, and hematologic abnormalities. Valvuloseptal development was normal, but L613V/+ mice exhibited eccentric cardiac hypertrophy and aberrant cardiac fetal gene expression, and decompensated following pressure overload. Agonist-evoked MEK-ERK activation was enhanced in multiple cell types, and postnatal MEK inhibition normalized the growth, facial, and cardiac defects in L613V/+ mice. These data show that different NS genes have intrinsically distinct pathological effects, demonstrate that enhanced MEK-ERK activity is critical for causing HCM and other RAF1-mutant NS phenotypes, and suggest a mutation-specific approach to the treatment of RASopathies.
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Affiliation(s)
- Xue Wu
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
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192
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Aizaki K, Sugai K, Saito Y, Nakagawa E, Sasaki M, Aoki Y, Matsubara Y. Cardio-facio-cutaneous syndrome with infantile spasms and delayed myelination. Brain Dev 2011; 33:166-9. [PMID: 20395089 DOI: 10.1016/j.braindev.2010.03.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2010] [Revised: 02/25/2010] [Accepted: 03/23/2010] [Indexed: 10/19/2022]
Abstract
A girl with cardio-facio-cutaneous (CFC) syndrome due to a BRAF gene mutation (c.1454T→C, p.L485S) experienced repetitive epileptic spasms at the corrected age of 4 months. Electroencephalograms revealed hypsarrhythmia, and magnetic resonance imaging identified delayed myelination and a hypoplastic corpus callosum. Various antiepileptic treatments, including adrenocorticotropic hormone therapy, were ineffective, although transient seizure control was achieved by a ketogenic diet and clorazepate dipotassium. However, seizures with epileptic foci at the bilateral posterior temporal areas re-aggravated and remained intractable; severe psychomotor delay persisted. This case indicated that infantile spasms in CFC syndrome can be difficult to control and may be accompanied by severe psychomotor retardation and abnormal myelination.
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Affiliation(s)
- Koichi Aizaki
- Department of Child Neurology, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
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193
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Cardiotoxicity of kinase inhibitors: the prediction and translation of preclinical models to clinical outcomes. Nat Rev Drug Discov 2011; 10:111-26. [PMID: 21283106 DOI: 10.1038/nrd3252] [Citation(s) in RCA: 258] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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194
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Runtuwene V, van Eekelen M, Overvoorde J, Rehmann H, Yntema HG, Nillesen WM, van Haeringen A, van der Burgt I, Burgering B, den Hertog J. Noonan syndrome gain-of-function mutations in NRAS cause zebrafish gastrulation defects. Dis Model Mech 2011; 4:393-9. [PMID: 21263000 PMCID: PMC3097460 DOI: 10.1242/dmm.007112] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Noonan syndrome is a relatively common developmental disorder that is characterized by reduced growth, wide-set eyes and congenital heart defects. Noonan syndrome is associated with dysregulation of the Ras–mitogen-activated-protein-kinase (MAPK) signaling pathway. Recently, two mutations in NRAS were reported to be associated with Noonan syndrome, T50I and G60E. Here, we report a mutation in NRAS, resulting in an I24N amino acid substitution, that we identified in an individual bearing typical Noonan syndrome features. The I24N mutation activates N-Ras, resulting in enhanced downstream signaling. Expression of N-Ras-I24N, N-Ras-G60E or the strongly activating mutant N-Ras-G12V, which we included as a positive control, results in developmental defects in zebrafish embryos, demonstrating that these activating N-Ras mutants are sufficient to induce developmental disorders. The defects in zebrafish embryos are reminiscent of symptoms in individuals with Noonan syndrome and phenocopy the defects that other Noonan-syndrome-associated genes induce in zebrafish embryos. MEK inhibition completely rescued the activated N-Ras-induced phenotypes, demonstrating that these defects are mediated exclusively by Ras-MAPK signaling. In conclusion, mutations in NRAS from individuals with Noonan syndrome activated N-Ras signaling and induced developmental defects in zebrafish embryos, indicating that activating mutations in NRAS cause Noonan syndrome.
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Affiliation(s)
- Vincent Runtuwene
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
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195
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Gremer L, Merbitz-Zahradnik T, Dvorsky R, Cirstea IC, Kratz CP, Zenker M, Wittinghofer A, Ahmadian MR. Germline KRAS mutations cause aberrant biochemical and physical properties leading to developmental disorders. Hum Mutat 2011; 32:33-43. [PMID: 20949621 PMCID: PMC3117284 DOI: 10.1002/humu.21377] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Accepted: 09/05/2010] [Indexed: 02/06/2023]
Abstract
The KRAS gene is the most common locus for somatic gain-of-function mutations in human cancer. Germline KRAS mutations were shown recently to be associated with developmental disorders, including Noonan syndrome (NS), cardio-facio-cutaneous syndrome (CFCS), and Costello syndrome (CS). The molecular basis of this broad phenotypic variability has in part remained elusive so far. Here, we comprehensively analyzed the biochemical and structural features of ten germline KRAS mutations using physical and cellular biochemistry. According to their distinct biochemical and structural alterations, the mutants can be grouped into five distinct classes, four of which markedly differ from RAS oncoproteins. Investigated functional alterations comprise the enhancement of intrinsic and guanine nucleotide exchange factor (GEF) catalyzed nucleotide exchange, which is alternatively accompanied by an impaired GTPase-activating protein (GAP) stimulated GTP hydrolysis, an overall loss of functional properties, and a deficiency in effector interaction. In conclusion, our data underscore the important role of RAS in the pathogenesis of the group of related disorders including NS, CFCS, and CS, and provide clues to the high phenotypic variability of patients with germline KRAS mutations.
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Affiliation(s)
- Lothar Gremer
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
- Max-Planck Institute of Molecular Physiology, Department of Structural Biology, Dortmund, Germany
| | - Torsten Merbitz-Zahradnik
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
- Max-Planck Institute of Molecular Physiology, Department of Structural Biology, Dortmund, Germany
| | - Radovan Dvorsky
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
- Max-Planck Institute of Molecular Physiology, Department of Structural Biology, Dortmund, Germany
| | - Ion C. Cirstea
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | | | - Martin Zenker
- Institute of Human Genetics, University Hospital Magdeburg, Magdeburg, Germany
| | - Alfred Wittinghofer
- Max-Planck Institute of Molecular Physiology, Department of Structural Biology, Dortmund, Germany
| | - Mohammad Reza Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
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196
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Keshet Y, Seger R. The MAP kinase signaling cascades: a system of hundreds of components regulates a diverse array of physiological functions. Methods Mol Biol 2010; 661:3-38. [PMID: 20811974 DOI: 10.1007/978-1-60761-795-2_1] [Citation(s) in RCA: 412] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Sequential activation of kinases within the mitogen-activated protein (MAP) kinase (MAPK) cascades is a common, and evolutionary-conserved mechanism of signal transduction. Four MAPK cascades have been identified in the last 20 years and those are usually named according to the MAPK components that are the central building blocks of each of the cascades. These are the extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-Terminal kinase (JNK), p38, and ERK5 cascades. Each of these cascades consists of a core module of three tiers of protein kinases termed MAPK, MAPKK, and MAP3K, and often two additional tiers, the upstream MAP4K and the downstream MAPKAPK, which can complete five tiers of each cascade in certain cell lines or stimulations. The transmission of the signal via each cascade is mediated by sequential phosphorylation and activation of the components in the sequential tiers. These cascades cooperate in transmitting various extracellular signals and thus control a large number of distinct and even opposing cellular processes such as proliferation, differentiation, survival, development, stress response, and apoptosis. One way by which the specificity of each cascade is regulated is through the existence of several distinct components in each tier of the different cascades. About 70 genes, which are each translated to several alternatively spliced isoforms, encode the entire MAPK system, and allow the wide array of cascade's functions. These components, their regulation, as well as their involvement together with other mechanisms in the determination of signaling specificity by the MAPK cascade is described in this review. Mis-regulation of the MAPKs signals usually leads to diseases such as cancer and diabetes; therefore, studying the mechanisms of specificity-determination may lead to better understanding of these signaling-related diseases.
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Affiliation(s)
- Yonat Keshet
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot, Israel
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197
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Multiple oncogenic mutations and clonal relationship in spatially distinct benign human epidermal tumors. Proc Natl Acad Sci U S A 2010; 107:20780-5. [PMID: 21078999 DOI: 10.1073/pnas.1008365107] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Malignant tumors result from the accumulation of genetic alterations in oncogenes and tumor suppressor genes. Much less is known about the genetic changes in benign tumors. Seborrheic keratoses (SK) are very frequent benign human epidermal tumors without malignant potential. We performed a comprehensive mutational screen of genes in the FGFR3-RAS-MAPK and phosphoinositide 3-kinase (PI3K)-AKT pathways from 175 SK, including multiple lesions from each patient. SK commonly harbored multiple bona fide oncogenic mutations in FGFR3, PIK3CA, KRAS, HRAS, EGFR, and AKT1 oncogenes but not in tumor suppressor genes TSC1 and PTEN. Despite the occurrence of oncogenic mutations and the evidence for downstream ERK/MAPK and PI3K pathway signaling, we did not find induction of senescence or a DNA damage response. Array comparative genomic hybridization (aCGH) analysis revealed that SK are genetically stable. The pattern of oncogenic mutations and X chromosome inactivation departs significantly from randomness and indicates that spatially independent lesions from a given patient share a clonal relationship. Our findings show that multiple oncogenic mutations in the major signaling pathways involved in cancer are not sufficient to drive malignant tumor progression. Furthermore, our data provide clues on the origin and spread of oncogenic mutations in tissues, suggesting that apparently independent (multicentric) adult benign tumors may have a clonal origin.
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198
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Coffin–Lowry syndrome: A role for RSK2 in mammalian neurogenesis. Dev Biol 2010; 347:348-59. [DOI: 10.1016/j.ydbio.2010.08.035] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 08/27/2010] [Accepted: 08/27/2010] [Indexed: 11/18/2022]
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199
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Kobayashi T, Aoki Y, Niihori T, Cavé H, Verloes A, Okamoto N, Kawame H, Fujiwara I, Takada F, Ohata T, Sakazume S, Ando T, Nakagawa N, Lapunzina P, Meneses AG, Gillessen-Kaesbach G, Wieczorek D, Kurosawa K, Mizuno S, Ohashi H, David A, Philip N, Guliyeva A, Narumi Y, Kure S, Tsuchiya S, Matsubara Y. Molecular and clinical analysis of RAF1 in Noonan syndrome and related disorders: dephosphorylation of serine 259 as the essential mechanism for mutant activation. Hum Mutat 2010; 31:284-94. [PMID: 20052757 DOI: 10.1002/humu.21187] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Noonan syndrome (NS) and related disorders are autosomal dominant disorders characterized by heart defects, facial dysmorphism, ectodermal abnormalities, and mental retardation. The dysregulation of the RAS/MAPK pathway appears to be a common molecular pathogenesis of these disorders: mutations in PTPN11, KRAS, and SOS1 have been identified in patients with NS, those in KRAS, BRAF, MAP2K1, and MAP2K2 in patients with CFC syndrome, and those in HRAS mutations in Costello syndrome patients. Recently, mutations in RAF1 have been also identified in patients with NS and two patients with LEOPARD (multiple lentigines, electrocardiographic conduction abnormalities, ocular hypertelorism, pulmonary stenosis, abnormal genitalia, retardation of growth, and sensorineural deafness) syndrome. In the current study, we identified eight RAF1 mutations in 18 of 119 patients with NS and related conditions without mutations in known genes. We summarized clinical manifestations in patients with RAF1 mutations as well as those in NS patients withPTPN11, SOS1, or KRAS mutations previously reported. Hypertrophic cardiomyopathy and short stature were found to be more frequently observed in patients with RAF1 mutations. Mutations in RAF1 were clustered in the conserved region 2 (CR2) domain, which carries an inhibitory phosphorylation site (serine at position 259; S259). Functional studies revealed that the RAF1 mutants located in the CR2 domain resulted in the decreased phosphorylation of S259, and that mutant RAF1 then dissociated from 14-3-3, leading to a partial ERK activation. Our results suggest that the dephosphorylation of S259 is the primary pathogenic mechanism in the activation of RAF1 mutants located in the CR2 domain as well as of downstream ERK.
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Affiliation(s)
- Tomoko Kobayashi
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan
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200
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Groebe K, Hayess K, Klemm-Manns M, Schwall G, Wozny W, Steemans M, Peters AK, Sastri C, Jaeckel P, Stegmann W, Zengerling H, Schöpf R, Poznanovic S, Stummann TC, Seiler A, Spielmann H, Schrattenholz A. Protein Biomarkers for in Vitro Testing of Embryotoxicity. J Proteome Res 2010; 9:5727-38. [DOI: 10.1021/pr100514e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Karlfried Groebe
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Katrin Hayess
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Martina Klemm-Manns
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Gerhard Schwall
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Woijciech Wozny
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Margino Steemans
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Annelieke K. Peters
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Chaturvedala Sastri
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Petra Jaeckel
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Werner Stegmann
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Helmut Zengerling
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Rainer Schöpf
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Slobodan Poznanovic
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Tina C. Stummann
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Andrea Seiler
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - Horst Spielmann
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
| | - André Schrattenholz
- ProteoSys AG, Carl-Zeiss.-Str. 51, D-55129 Mainz, Germany, Federal Institute for Risk Assessment, Center for Alternative Methods to Animal Experiments - ZEBET Diedersdorfer Weg 1, 12277 Berlin, Germany, Johnson & Johnson PRD, a division of Janssen Pharmaceutical, 2340 Beerse, Belgium, European Centre for the Validation of Alternative Methods (ECVAM) (IHCP, JRC), Via Fermi, 121020 Ispra, Italy
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