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Kuhn E, Natacci F, Corbo M, Pisani L, Ferrero S, Bulfamante G, Gambini D. The Contribution of Oxidative Stress to NF1-Altered Tumors. Antioxidants (Basel) 2023; 12:1557. [PMID: 37627552 PMCID: PMC10451967 DOI: 10.3390/antiox12081557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/02/2023] [Accepted: 08/03/2023] [Indexed: 08/27/2023] Open
Abstract
The neurofibromatosis-1 gene (NF1) was initially characterized because its germline mutation is responsible for an inherited syndromic disease predisposing tumor development, in particular neurofibromas but also various malignancies. Recently, large-scale tumor sequencing efforts have demonstrated NF1 as one of the most frequently mutated genes in human cancer, being mutated in approximately 5-10% of all tumors, especially in malignant peripheral nerve sheath tumors and different skin tumors. NF1 acts as a tumor suppressor gene that encodes neurofibromin, a large protein that controls neoplastic transformation through several molecular mechanisms. On the other hand, neurofibromin loss due to NF1 biallelic inactivation induces tumorigenic hyperactivation of Ras and mTOR signaling pathways. Moreover, neurofibromin controls actin cytoskeleton structure and the metaphase-anaphase transition. Consequently, neurofibromin deficiency favors cell mobility and proliferation as well as chromosomal instability and aneuploidy, respectively. Growing evidence supports the role of oxidative stress in NF1-related tumorigenesis. Neurofibromin loss induces oxidative stress both directly and through Ras and mTOR signaling activation. Notably, innovative therapeutic approaches explore drug combinations that further increase reactive oxygen species to boost the oxidative unbalance of NF1-altered cancer cells. In our paper, we review NF1-related tumors and their pathogenesis, highlighting the twofold contribution of oxidative stress, both tumorigenic and therapeutic.
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Affiliation(s)
- Elisabetta Kuhn
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20122 Milan, Italy; (S.F.); (G.B.)
- Pathology Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Federica Natacci
- Medical Genetics Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy;
| | - Massimo Corbo
- Department of Neurorehabilitation Sciences, Casa di Cura Igea, 20144 Milan, Italy; (M.C.); (L.P.); (D.G.)
| | - Luigi Pisani
- Department of Neurorehabilitation Sciences, Casa di Cura Igea, 20144 Milan, Italy; (M.C.); (L.P.); (D.G.)
| | - Stefano Ferrero
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20122 Milan, Italy; (S.F.); (G.B.)
- Pathology Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Gaetano Bulfamante
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20122 Milan, Italy; (S.F.); (G.B.)
- Human Pathology and Molecular Pathology, TOMA Advanced Biomedical Assays S.p.A., 21052 Busto Arsizio, Italy
| | - Donatella Gambini
- Department of Neurorehabilitation Sciences, Casa di Cura Igea, 20144 Milan, Italy; (M.C.); (L.P.); (D.G.)
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2
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Tabebi M, Frikha F, Volpe M, Gimm O, Söderkvist P. Domain landscapes of somatic NF1 mutations in pheochromocytoma and paraganglioma. Gene 2023; 872:147432. [PMID: 37062455 DOI: 10.1016/j.gene.2023.147432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/23/2023] [Accepted: 04/11/2023] [Indexed: 04/18/2023]
Abstract
Pheochromocytoma and paraganglioma (PPGL), are rare neuroendocrine tumors arising from the adrenal medulla and extra-adrenal paraganglia, respectively. Up to about 60% are explained by germline or somatic mutations in one of the major known susceptibility genes e.g., inNF1,RET,VHL, SDHx,MAXandHRAS. Targeted Next Generation Sequencing was performed in 14 sporadic tumors using a panel including 26 susceptibility genes to characterize the mutation profile. A total of 6 germline and 8 somatic variants were identified. The most frequent somatic mutations were found in NF1(36%), four have not been reported earlier in PCC or PGL. Gene expression profile analysis showed that NF1 mutated tumors are classified into RTK3 subtype, cluster 2, with a high expression of genes associated with chromaffin cell differentiation, and into a RTK2 subtype, cluster 2, as well with overexpression of genes associated with cortisol biosynthesis. On the other hand, by analyzing the entire probe set on the array and TCGA data, ALDOC was found as the most significantly down regulated gene in NF1-mutated tumors compared to NF1-wild-type. Differential gene expression analysis showed a significant difference between Nt - and Ct-NF1 domains in mutated tumors probably engaging different cellular pathways. Notably, we had a metastatic PCC with a Ct-NF1 frameshift mutation and when performing protein docking analysis, Ct-NF1 showed an interaction with Nt-FAK suggesting their involvement in cell adhesion and cell growth. These results show that depending on the location of the NF1-mutation different pathways are activated in PPGLs. Further studies are required to clarify their clinical significance.
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Affiliation(s)
- Mouna Tabebi
- Department of Biomedical and Clinical Sciences (BKV), Linköping University, 58183 Linköping, Sweden.
| | - Fakher Frikha
- Laboratory of Molecular and Cellular Screening Processes, Center of Biotechnology of Sfax, University of Sfax, Sfax, Tunisia
| | - Massimiliano Volpe
- Clinical Genomics Linköping, Linköping University, 581 83 Linköping, Sweden
| | - Oliver Gimm
- Department of Surgery and Department of Biomedical and Clinical Sciences (BKV), Linköping University, 58183 Linköping, Sweden
| | - Peter Söderkvist
- Department of Biomedical and Clinical Sciences (BKV), Linköping University, 58183 Linköping, Sweden; Clinical Genomics Linköping, Linköping University, 581 83 Linköping, Sweden
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Paterra R, Bettinaglio P, Borghi A, Mangano E, Tritto V, Cesaretti C, Schettino C, Bordoni R, Santoro C, Avignone S, Moscatelli M, Melone MAB, Saletti V, Piluso G, Natacci F, Riva P, Eoli M. A Translational Approach to Spinal Neurofibromatosis: Clinical and Molecular Insights from a Wide Italian Cohort. Cancers (Basel) 2022; 15:cancers15010059. [PMID: 36612057 PMCID: PMC9817775 DOI: 10.3390/cancers15010059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 12/07/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022] Open
Abstract
Spinal neurofibromatosis (SNF), a phenotypic subclass of neurofibromatosis 1 (NF1), is characterized by bilateral neurofibromas involving all spinal roots. In order to deepen the understanding of SNF’s clinical and genetic features, we identified 81 patients with SNF, 55 from unrelated families, and 26 belonging to 19 families with at least 1 member affected by SNF, and 106 NF1 patients aged >30 years without spinal tumors. A comprehensive NF1 mutation screening was performed using NGS panels, including NF1 and several RAS pathway genes. The main features of the SNF subjects were a higher number of internal neurofibromas (p < 0.001), nerve root swelling (p < 0.001), and subcutaneous neurofibromas (p = 0.03), while hyperpigmentation signs were significantly less frequent compared with the classical NF1-affected cohorts (p = 0.012). Fifteen patients underwent neurosurgical intervention. The histological findings revealed neurofibromas in 13 patients and ganglioneuromas in 2 patients. Phenotypic variability within SNF families was observed. The proportion of missense mutations was higher in the SNF cases than in the classical NF1 group (21.40% vs. 7.5%, p = 0.007), conferring an odds ratio (OR) of 3.34 (CI = 1.33−10.78). Two unrelated familial SNF cases harbored in trans double NF1 mutations that seemed to have a subclinical worsening effect on the clinical phenotype. Our study, with the largest series of SNF patients reported to date, better defines the clinical and genetic features of SNF, which could improve the management and genetic counseling of NF1.
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Affiliation(s)
- Rosina Paterra
- Molecular Neuroncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20122 Milano, Italy
| | - Paola Bettinaglio
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), University of Milan, Segrate, 20122 Milan, Italy
| | - Arianna Borghi
- Molecular Neuroncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20122 Milano, Italy
| | - Eleonora Mangano
- Institute of Biomedical Technologies (ITB) National Research Center (CNR), ITB-CNR, Segrate, 20122 Milan, Italy
| | - Viviana Tritto
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), University of Milan, Segrate, 20122 Milan, Italy
| | - Claudia Cesaretti
- Medical Genetics Unit, Woman-Child-Newborn Department, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, 20122 Milano, Italy
| | - Carla Schettino
- Department of Advanced Medical and Surgical Sciences, 2nd Division of Neurology, Center for Rare Diseases and InterUniversity Center for Research in Neurosciences, University of Campania “Luigi Vanvitelli”, 81100 Naples, Italy
| | - Roberta Bordoni
- Institute of Biomedical Technologies (ITB) National Research Center (CNR), ITB-CNR, Segrate, 20122 Milan, Italy
| | - Claudia Santoro
- Neurofibromatosis Referral Center, Department of Woman, Child and of General and Specialized Surgery, and Clinic of Child and Adolescent Neuropsychiatry, Department of Mental Health, Physical and Preventive Medicine, University of Campania “Luigi Vanvitelli”, 81100 Naples, Italy
| | - Sabrina Avignone
- Neuroradiology Department, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, 20122 Milano, Italy
| | - Marco Moscatelli
- Neuroradiology Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milano, Italy
| | - Mariarosa Anna Beatrice Melone
- Department of Advanced Medical and Surgical Sciences, 2nd Division of Neurology, Center for Rare Diseases and InterUniversity Center for Research in Neurosciences, University of Campania “Luigi Vanvitelli”, 81100 Naples, Italy
- Sbarro Institute for Cancer Research and Molecular Medicine, Center for Biotechnology, Temple University, Philadelphia, PA 19122, USA
| | - Veronica Saletti
- Developmental Neurology Unit, Mariani Foundation Center for Complex Disabilities, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy
| | - Giulio Piluso
- Department of Precision Medicine, Università degli Studi della Campania “Luigi Vanvitelli”, 81100 Naples, Italy
| | - Federica Natacci
- Medical Genetics Unit, Woman-Child-Newborn Department, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, 20122 Milano, Italy
| | - Paola Riva
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), University of Milan, Segrate, 20122 Milan, Italy
- Correspondence: (P.R.); (M.E.); Tel.: +39-02-503130462 (P.R.); +39-02-23942285 (M.E.)
| | - Marica Eoli
- Molecular Neuroncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20122 Milano, Italy
- Correspondence: (P.R.); (M.E.); Tel.: +39-02-503130462 (P.R.); +39-02-23942285 (M.E.)
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4
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Multi-omics study revealed the genetic basis of beer flavor quality in yeast. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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5
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Anastasaki C, Orozco P, Gutmann DH. RAS and beyond: the many faces of the neurofibromatosis type 1 protein. Dis Model Mech 2022; 15:274437. [PMID: 35188187 PMCID: PMC8891636 DOI: 10.1242/dmm.049362] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Neurofibromatosis type 1 is a rare neurogenetic syndrome, characterized by pigmentary abnormalities, learning and social deficits, and a predisposition for benign and malignant tumor formation caused by germline mutations in the NF1 gene. With the cloning of the NF1 gene and the recognition that the encoded protein, neurofibromin, largely functions as a negative regulator of RAS activity, attention has mainly focused on RAS and canonical RAS effector pathway signaling relevant to disease pathogenesis and treatment. However, as neurofibromin is a large cytoplasmic protein the RAS regulatory domain of which occupies only 10% of its entire coding sequence, both canonical and non-canonical RAS pathway modulation, as well as the existence of potential non-RAS functions, are becoming apparent. In this Special article, we discuss our current understanding of neurofibromin function.
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Affiliation(s)
- Corina Anastasaki
- Department of Neurology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Paola Orozco
- Department of Neurology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - David H Gutmann
- Department of Neurology, Washington University School of Medicine, St Louis, MO 63110, USA
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6
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Mo J, Moye SL, McKay RM, Le LQ. Neurofibromin and suppression of tumorigenesis: beyond the GAP. Oncogene 2022; 41:1235-1251. [PMID: 35066574 PMCID: PMC9063229 DOI: 10.1038/s41388-021-02156-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/01/2021] [Accepted: 12/13/2021] [Indexed: 12/15/2022]
Abstract
Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disease and one of the most common inherited tumor predisposition syndromes, affecting 1 in 3000 individuals worldwide. The NF1 gene encodes neurofibromin, a large protein with RAS GTP-ase activating (RAS-GAP) activity, and loss of NF1 results in increased RAS signaling. Neurofibromin contains many other domains, and there is considerable evidence that these domains play a role in some manifestations of NF1. Investigating the role of these domains as well as the various signaling pathways that neurofibromin regulates and interacts with will provide a better understanding of how neurofibromin acts to suppress tumor development and potentially open new therapeutic avenues. In this review, we discuss what is known about the structure of neurofibromin, its interactions with other proteins and signaling pathways, its role in development and differentiation, and its function as a tumor suppressor. Finally, we discuss the latest research on potential therapeutics for neurofibromin-deficient neoplasms.
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Affiliation(s)
- Juan Mo
- Department of Dermatology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9069, USA
| | - Stefanie L. Moye
- Department of Dermatology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9069, USA
| | - Renee M. McKay
- Department of Dermatology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9069, USA
| | - Lu Q. Le
- Department of Dermatology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9069, USA,Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9069, USA,UTSW Comprehensive Neurofibromatosis Clinic, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9069, USA,Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9069, USA,O’Donnell Brain Institute, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9069, USA,Correspondence and requests for materials should be addressed to Lu Q. Le.
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7
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Case series of congenital pseudarthrosis of the tibia unfulfilling neurofibromatosis type 1 diagnosis: 21% with somatic NF1 haploinsufficiency in the periosteum. Hum Genet 2022; 141:1371-1383. [DOI: 10.1007/s00439-021-02429-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 12/29/2021] [Indexed: 12/17/2022]
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8
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Lutz S, Van Dyke K, Feraru MA, Albert FW. Multiple epistatic DNA variants in a single gene affect gene expression in trans. Genetics 2022; 220:iyab208. [PMID: 34791209 PMCID: PMC8733636 DOI: 10.1093/genetics/iyab208] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/09/2021] [Indexed: 01/08/2023] Open
Abstract
DNA variants that alter gene expression in trans are important sources of phenotypic variation. Nevertheless, the identity of trans-acting variants remains poorly understood. Single causal variants in several genes have been reported to affect the expression of numerous distant genes in trans. Whether these simple molecular architectures are representative of trans-acting variation is unknown. Here, we studied the large RAS signaling regulator gene IRA2, which contains variants with extensive trans-acting effects on gene expression in the yeast Saccharomyces cerevisiae. We used systematic CRISPR-based genome engineering and a sensitive phenotyping strategy to dissect causal variants to the nucleotide level. In contrast to the simple molecular architectures known so far, IRA2 contained at least seven causal nonsynonymous variants. The effects of these variants were modulated by nonadditive, epistatic interactions. Two variants at the 5'-end affected gene expression and growth only when combined with a third variant that also had no effect in isolation. Our findings indicate that the molecular basis of trans-acting genetic variation may be considerably more complex than previously appreciated.
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Affiliation(s)
- Sheila Lutz
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Krisna Van Dyke
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Matthew A Feraru
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Frank W Albert
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
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9
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Bergoug M, Doudeau M, Godin F, Mosrin C, Vallée B, Bénédetti H. Neurofibromin Structure, Functions and Regulation. Cells 2020; 9:cells9112365. [PMID: 33121128 PMCID: PMC7692384 DOI: 10.3390/cells9112365] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/21/2020] [Accepted: 10/26/2020] [Indexed: 12/13/2022] Open
Abstract
Neurofibromin is a large and multifunctional protein encoded by the tumor suppressor gene NF1, mutations of which cause the tumor predisposition syndrome neurofibromatosis type 1 (NF1). Over the last three decades, studies of neurofibromin structure, interacting partners, and functions have shown that it is involved in several cell signaling pathways, including the Ras/MAPK, Akt/mTOR, ROCK/LIMK/cofilin, and cAMP/PKA pathways, and regulates many fundamental cellular processes, such as proliferation and migration, cytoskeletal dynamics, neurite outgrowth, dendritic-spine density, and dopamine levels. The crystallographic structure has been resolved for two of its functional domains, GRD (GAP-related (GTPase-activating protein) domain) and SecPH, and its post-translational modifications studied, showing it to be localized to several cell compartments. These findings have been of particular interest in the identification of many therapeutic targets and in the proposal of various therapeutic strategies to treat the symptoms of NF1. In this review, we provide an overview of the literature on neurofibromin structure, function, interactions, and regulation and highlight the relationships between them.
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10
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Nuclear Isoforms of Neurofibromin Are Required for Proper Spindle Organization and Chromosome Segregation. Cells 2020; 9:cells9112348. [PMID: 33114250 PMCID: PMC7690890 DOI: 10.3390/cells9112348] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 10/20/2020] [Accepted: 10/22/2020] [Indexed: 12/30/2022] Open
Abstract
Mitotic spindles are highly organized, microtubule (MT)-based, transient structures that serve the fundamental function of unerring chromosome segregation during cell division and thus of genomic stability during tissue morphogenesis and homeostasis. Hence, a multitude of MT-associated proteins (MAPs) regulates the dynamic assembly of MTs in preparation for mitosis. Some tumor suppressors, normally functioning to prevent tumor development, have now emerged as significant MAPs. Among those, neurofibromin, the product of the Neurofibromatosis-1 gene (NF1), a major Ras GTPase activating protein (RasGAP) in neural cells, controls also the critical function of chromosome congression in astrocytic cellular contexts. Cell type- and development-regulated splicings may lead to the inclusion or exclusion of NF1exon51, which bears a nuclear localization sequence (NLS) for nuclear import at G2; yet the functions of the produced NLS and ΔNLS neurofibromin isoforms have not been previously addressed. By using a lentiviral shRNA system, we have generated glioblastoma SF268 cell lines with conditional knockdown of NLS or ΔNLS transcripts. In dissecting the roles of NLS or ΔNLS neurofibromins, we found that NLS-neurofibromin knockdown led to increased density of cytosolic MTs but loss of MT intersections, anastral spindles featuring large hollows and abnormal chromosome positioning, and finally abnormal chromosome segregation and increased micronuclei frequency. Therefore, we propose that NLS neurofibromin isoforms exert prominent mitotic functions.
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11
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Cui XW, Ren JY, Gu YH, Li QF, Wang ZC. NF1, Neurofibromin and Gene Therapy: Prospects of Next-Generation Therapy. Curr Gene Ther 2020; 20:100-108. [PMID: 32767931 DOI: 10.2174/1566523220666200806111451] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 07/10/2020] [Accepted: 07/14/2020] [Indexed: 12/28/2022]
Abstract
Neurofibromatosis type 1 [NF1] is an autosomal dominant genetic disorder affecting multiple organs. NF1 is well known for its various clinical manifestations, including café-au-late macules, Lisch nodules, bone deformity and neurofibromas. However, there is no effective therapy for NF1. Current therapies are aimed at alleviating NF1 clinical symptoms but not curing the disease. By altering pathogenic genes, gene therapy regulates cell activities at the nucleotide level. In this review, we described the structure and functions of neurofibromin domains, including GAP-related domain [GRD], cysteine-serine rich domain [CSRD], leucine-rich domain [LRD] and C-terminal domain [CTD], which respectively alter downstream pathways. By transfecting isolated sequences of these domains, researchers can partially restore normal cell functions in neurofibroma cell lines. Furthermore, recombinant transgene sequences may be designed to encode truncated proteins, which is functional and easy to be packaged into viral vectors. In addition, the treatment effect of gene therapy is also determined by various factors such as the vectors selection, transgene packaging strategies and drug administration. We summarized multiple NF1 gene therapy strategies and discussed their feasibility from multiple angles. Different protein domains alter the function and downstream pathways of neurofibromin.
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Affiliation(s)
- Xi-Wei Cui
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Jie-Yi Ren
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Yi-Hui Gu
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Qing-Feng Li
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Zhi-Chao Wang
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
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12
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Melloni G, Eoli M, Cesaretti C, Bianchessi D, Ibba MC, Esposito S, Scuvera G, Morcaldi G, Micheli R, Piozzi E, Avignone S, Chiapparini L, Pantaleoni C, Natacci F, Finocchiaro G, Saletti V. Risk of Optic Pathway Glioma in Neurofibromatosis Type 1: No Evidence of Genotype-Phenotype Correlations in A Large Independent Cohort. Cancers (Basel) 2019; 11:cancers11121838. [PMID: 31766501 PMCID: PMC6966666 DOI: 10.3390/cancers11121838] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 11/17/2019] [Accepted: 11/18/2019] [Indexed: 11/16/2022] Open
Abstract
The occurrence of optic pathway gliomas (OPGs) in children with neurofibromatosis type 1 (NF1) still raises many questions regarding screening and surveillance because of the lack of robust prognostic factors. Recent studies of an overall cohort of 381 patients have suggested that the genotype may be the main determinant of the development of OPG, with the risk being higher in patients harbouring NF1 mutations in the 5’ tertile and the cysteine/serine-rich domain. In an attempt to confirm this hypothesis, we used strict criteria to select a large independent cohort of 309 NF1 patients with defined constitutional NF1 mutations and appropriate brain images (255 directly enrolled and 54 as a result of a literature search). One hundred and thirty-two patients had OPG and 177 did not. The association of the position (tertiles and functional domains) and type of NF1 mutation with the development of OPG was analysed using the χ2 test and Fisher’s exact probability test; odds ratios (ORs) with 95% confidence intervals were calculated, and Bonferroni’s correction for multiple comparisons was applied; multiple logistic regression was also used to study genotype–phenotype associations further. Our findings show no significant correlation between the site/type of NF1 mutation and the risk of OPG, and thus do not support the hypothesis that certain constitutional mutations provide prognostic information in this regard. In addition, we combined our cohort with a previously described cohort of 381 patients for a total of 690 patients and statistically re-analysed the results. The re-analysis confirmed that there were no correlations between the site (tertile and domain) and the risk of OPG, thus further strengthening our conclusions.
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Affiliation(s)
- Giulia Melloni
- Developmental Neurology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20121 Milan, Italy; (G.M.); (S.E.); (C.P.)
| | - Marica Eoli
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20121 Milan, Italy; (M.E.); (D.B.); (M.C.I.); (G.F.)
| | - Claudia Cesaretti
- Medical Genetics Unit, Woman-Child-Newborn Department, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, via Francesco Sforza 28, 20122 Milan, Italy; (C.C.); (F.N.)
| | - Donatella Bianchessi
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20121 Milan, Italy; (M.E.); (D.B.); (M.C.I.); (G.F.)
| | - Maria Cristina Ibba
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20121 Milan, Italy; (M.E.); (D.B.); (M.C.I.); (G.F.)
| | - Silvia Esposito
- Developmental Neurology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20121 Milan, Italy; (G.M.); (S.E.); (C.P.)
| | - Giulietta Scuvera
- Department of Pathophysiology and Transplantation, Pediatric Highly Intensive Care Unit, Università degli Studi di Milano, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, via Francesco Sforza 28, 20122 Milan, Italy;
| | - Guido Morcaldi
- Paediatric Neurology and Neuromuscular Disorders, University of Genoa and Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147 Genoa, Italy;
| | - Roberto Micheli
- Pediatric Neuropsychiatry, Spedali Civili of Brescia, Piazzale Spedali Civili 1, 25125 Brescia, Italy;
| | - Elena Piozzi
- Pediatric Department, ASST Grande Ospedale Metropolitano Niguarda, Piazza Ospedale Maggiore 3, 20162 Milan, Italy;
| | - Sabrina Avignone
- Neuroradiology Department, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, University of Milan, via Francesco Sforza 28, 20122 Milan, Italy;
| | - Luisa Chiapparini
- Neuroradiology Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20121 Milan, Italy;
| | - Chiara Pantaleoni
- Developmental Neurology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20121 Milan, Italy; (G.M.); (S.E.); (C.P.)
| | - Federica Natacci
- Medical Genetics Unit, Woman-Child-Newborn Department, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, via Francesco Sforza 28, 20122 Milan, Italy; (C.C.); (F.N.)
| | - Gaetano Finocchiaro
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20121 Milan, Italy; (M.E.); (D.B.); (M.C.I.); (G.F.)
| | - Veronica Saletti
- Developmental Neurology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20121 Milan, Italy; (G.M.); (S.E.); (C.P.)
- Correspondence:
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Karouzaki S, Peta C, Tsirimonaki E, Mangoura D. PKCε-dependent H-Ras activation encompasses the recruitment of the RasGEF SOS1 and of the RasGAP neurofibromin in the lipid rafts of embryonic neurons. Neurochem Int 2019; 131:104582. [PMID: 31629778 DOI: 10.1016/j.neuint.2019.104582] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 09/27/2019] [Accepted: 10/15/2019] [Indexed: 01/07/2023]
Abstract
The spatial organization of plasma membrane proteins is a key factor in the generation of distinct signal outputs, especially for PKC/Ras/ERK signalling. Regulation of activation of the membrane-bound Ras, critical for neuronal differentiation and highly specialized functions, is controlled by exchanges in nucleotides catalyzed by nucleotide exchange factors (GEFs) for GTP loading and Ras activation, and by Ras GTPase Activated Proteins (RasGAPs) that lead to activation of the intrinsic GTPase activity of Ras and thus its inactivation. PKCs are potent Ras activators yet the mechanistic details of these interactions, or the involvement of specific PKC isoforms are now beginning to be addressed. Even less known is the topology where RasGAPs terminate Ras activation. Towards this aim, we isolated lipid rafts from chick embryo neural tissue and primary neuronal cultures when PKCε is the prominent isoform and in combination with in vitro kinase assays, we now show that, in response the PKCε-specific activating peptide ψεRACK, an activated PKCε is recruited to lipid rafts; similar mobility was established when PKCε was physiologically activated with the Cannabinoid receptor 1 (CB1) agonist methanandamide. Activation of H-Ras for both agents was then established for the first time using in vivo RasGAP activity assays, which showed similar temporal profiles of activation and lateral mobility. Moreover, we found that the GEF SOS1, and the major neuronal RasGAP neurofibromin, a specific PKCε substrate, were both transiently significantly enriched in the rafts. Finally, our in silico analysis revealed a highly probable, conserved palmitoylation site adjacent to a CARC motif on neurofibromin, both of which are included only in the RasGAP related domain type I (GRDI) with the known high H-RasGAP activity. Taken together, these results suggest that PKCε activation regulates the spatial plasma membrane enrichments of both SOS1 and neurofibromin, thus controlling the output of activated H-Ras available for downstream signalling in neurons.
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Affiliation(s)
- Sophia Karouzaki
- Basic Research Center, Biomedical Research Foundation of the Academy of Athens, 4 Soranou Efesiou, Athens, 11527, Greece
| | - Charoula Peta
- Basic Research Center, Biomedical Research Foundation of the Academy of Athens, 4 Soranou Efesiou, Athens, 11527, Greece
| | - Emmanouella Tsirimonaki
- Basic Research Center, Biomedical Research Foundation of the Academy of Athens, 4 Soranou Efesiou, Athens, 11527, Greece
| | - Dimitra Mangoura
- Basic Research Center, Biomedical Research Foundation of the Academy of Athens, 4 Soranou Efesiou, Athens, 11527, Greece.
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14
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Qiao G, Jia X, Zhang Y, Chen B. Neurofibromin 1 expression is negatively correlated with malignancy and prognosis of epithelial ovarian cancer. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2019; 12:1702-1712. [PMID: 31933988 PMCID: PMC6947127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 12/19/2017] [Indexed: 06/10/2023]
Abstract
Epithelial ovarian cancer ranks as the 5th most deadly female cancer. However, few effective biomarkers have been identified for clinical application. Thus, it is critical to identify differentially expressed genes in epithelial ovarian cancer patient samples. Our work has focused on a tumor suppressor gene Neurofibromin 1 and its role in epithelial ovarian cancer pathology. We examined 124 samples of benign ovarian tissues, borderline ovarian tissues, and epithelial ovarian cancer tissues for NF1 expression by immunohistochemistry and further validated our results using RT-PCR and Western blot. We next analyzed the follow-up information with pathological features using Kaplan-Meier univariate survival analysis and Cox regression multivariate analysis. First, our results show that the mRNA level and protein level of NF1 are significantly decreased in epithelial ovarian cancer patients. Second, NF1 expression is negatively associated with 5-year overall survival, lymph node metastasis, and tumor size. Furthermore, our data also suggests that NF1 expression is a protective factor for epithelial ovarian cancer prognosis. NF1 is negatively regulated in EOC patients and low expression of NF1 is associated with lymph node metastasis. More importantly, patients that have lost NF1 showed poorer prognosis and five-year overall survival.
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Affiliation(s)
- Guyuan Qiao
- Department of Obstetrics and Gynecology, Xijing Hospital, Fourth Military Medical UniversityXi’an, Shaanxi, China
| | - Xuchun Jia
- Department of Pathology, Xijing Hospital, Fourth Military Medical UniversityXi’an, Shaanxi, China
| | - Ying Zhang
- Department of Obstetrics and Gynecology, 323 Hospital, People’s Liberation ArmyXi’an, Shaanxi, China
| | - Biliang Chen
- Department of Obstetrics and Gynecology, Xijing Hospital, Fourth Military Medical UniversityXi’an, Shaanxi, China
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15
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Xu M, Xiong H, Han Y, Li C, Mai S, Huang Z, Ai X, Guo Z, Zeng F, Guo Q. Identification of Mutation Regions on NF1 Responsible for High- and Low-Risk Development of Optic Pathway Glioma in Neurofibromatosis Type I. Front Genet 2018; 9:270. [PMID: 30087692 PMCID: PMC6066643 DOI: 10.3389/fgene.2018.00270] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 07/03/2018] [Indexed: 12/30/2022] Open
Abstract
Neurofibromatosis type I is a rare neurocutaneous syndrome resulting from loss-of-function mutations of NF1. The present study sought to determine a correlation between mutation regions on NF1 and the risk of developing optic pathway glioma (OPG) in patients with neurofibromatosis type I. A total of 215 patients with neurofibromatosis type I, from our clinic or previously reported literature, were included in the study after applying strict inclusion and exclusion criteria. Of these, 100 patients with OPG were classified into the OPG group and 115 patients without OPG (aged ≥ 10 years) were assigned to the Non-OPG group. Correlation between different mutation regions and risk of OPG was analyzed. The mutation clustering in the 5′ tertile of NF1 was not significantly different between OPG and Non-OPG groups (P = 0.131). Interestingly, patients with mutations in the cysteine/serine-rich domain of NF1 had a higher risk of developing OPG than patients with mutations in other regions [P = 0.019, adjusted odds ratio (OR) = 2.587, 95% confidence interval (CI) = 1.167–5.736], whereas those in the HEAT-like repeat region had a lower risk (P = 0.036, adjusted OR = 0.396, 95% CI = 0.166–0.942). This study confirms a new correlation between NF1 genotype and OPG phenotype in patients with neurofibromatosis type I, and provides novel insights into molecular functions of neurofibromin.
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Affiliation(s)
- Min Xu
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Hui Xiong
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Yanfang Han
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Chijun Li
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Shaozhen Mai
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.,Department of Dermatology, The Eighth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Zhongzhou Huang
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xuechen Ai
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Zhixuan Guo
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Fanqin Zeng
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Qing Guo
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
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Mahalingam M. NF1 and Neurofibromin: Emerging Players in the Genetic Landscape of Desmoplastic Melanoma. Adv Anat Pathol 2017; 24:1-14. [PMID: 27941538 DOI: 10.1097/pap.0000000000000131] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Neurofibromatosis type I (NF1), a monogenic disorder with an autosomal dominant mode of inheritance, is caused by alterations in the NF1 gene which codes for the protein neurofibromin. Functionally, NF1 is a tumor suppressor as it is GTPase-activating protein that negatively regulates the MAPK pathway. More recently, much attention has focused on the role of NF1 and neurofibromin in melanoma as mutations in NF1 have been found to constitute 1 of the 4 distinct genomic categories of melanoma, with the other 3 comprising BRAF, NRAS, and "triple-wild-type" subtypes. In this review, we parse the literature on NF1 and neurofibromin with a view to clarifying and gaining a better understanding of their precise role/s in melanomagenesis. We begin with a historic overview, followed by details regarding structure and function and characterization of neural crest development as a model for genetic reversion in neoplasia. Melanogenesis in NF1 sets the stage for the discussion on the roles of NF1 and neurofibromin in neural crest-derived neoplasms including melanoma with particular emphasis on NF1 and neurofibromin as markers of melanocyte dedifferentiation in desmoplastic melanoma.
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Affiliation(s)
- Meera Mahalingam
- VA Consolidated Laboratories, Department of Pathology and Laboratory Medicine, Dermatopathology Section, West Roxbury, MA
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17
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The Genomic Architecture of Interactions Between Natural Genetic Polymorphisms and Environments in Yeast Growth. Genetics 2016; 205:925-937. [PMID: 27903611 DOI: 10.1534/genetics.116.195487] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 11/22/2016] [Indexed: 12/26/2022] Open
Abstract
Gene-environment interaction (G×E) refers to the phenomenon that the same mutation has different phenotypic effects in different environments. Although quantitative trait loci (QTLs) exhibiting G×E have been reported, little is known about the general properties of G×E, and those of its underlying QTLs. Here, we use the genotypes of 1005 segregants from a cross between two Saccharomyces cerevisiae strains, and the growth rates of these segregants in 47 environments, to identify growth rate QTLs (gQTLs) in each environment, and QTLs that have different growth effects in each pair of environments (g×eQTLs) . The average number of g×eQTLs identified between two environments is 0.58 times the number of unique gQTLs identified in these environments, revealing a high abundance of G×E. Eighty-seven percent of g×eQTLs belong to gQTLs, supporting the practice of identifying g×eQTLs from gQTLs. Most g×eQTLs identified from gQTLs have concordant effects between environments, but, as the effect size of a mutation in one environment enlarges, the probability of antagonism in the other environment increases. Antagonistic g×eQTLs are enriched in dissimilar environments. Relative to gQTLs, g×eQTLs tend to occur at intronic and synonymous sites. The gene ontology (GO) distributions of gQTLs and g×eQTLs are significantly different, as are those of antagonistic and concordant g×eQTLs. Simulations based on the yeast data showed that ignoring G×E causes substantial missing heritability. Together, our findings reveal the genomic architecture of G×E in yeast growth, and demonstrate the importance of G×E in explaining phenotypic variation and missing heritability.
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Koliou X, Fedonidis C, Kalpachidou T, Mangoura D. Nuclear import mechanism of neurofibromin for localization on the spindle and function in chromosome congression. J Neurochem 2015; 136:78-91. [PMID: 26490262 DOI: 10.1111/jnc.13401] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 10/12/2015] [Accepted: 10/15/2015] [Indexed: 12/28/2022]
Abstract
Neurofibromatosis type-1 (NF-1) is caused by mutations in the tumor suppressor gene NF1; its protein product neurofibromin is a RasGTPase-activating protein, a property that has yet to explain aneuploidy, most often observed in astrocytes in NF-1. Here, we provide a mechanistic model for the regulated nuclear import of neurofibromin during the cell cycle and for a role in chromosome congression. Specifically, we demonstrate that neurofibromin, phosphorylated on Ser2808, a residue adjacent to a nuclear localization signal in the C-terminal domain (CTD), by Protein Kinase C-epsilon (PKC-ε), accumulates in a Ran-dependent manner and through binding to lamin in the nucleus at G2 in glioblastoma cells. Furthermore, we identify CTD as a tubulin-binding domain and show that a phosphomimetic substitution of its Ser2808 results in a predominantly nuclear localization. Confocal analysis shows that endogenous neurofibromin localizes on the centrosomes at interphase, as well as on the mitotic spindle, through direct associations with tubulins, in glioblastoma cells and primary astrocytes. More importantly, analysis of mitotic phenotypes after siRNA-mediated depletion shows that acute loss of this tumor suppressor protein leads to aberrant chromosome congression at the metaphase plate. Therefore, neurofibromin protein abundance and nuclear import are mechanistically linked to an error-free chromosome congression. Concerned with neurofibromin's, a tumor suppressor, mechanism of action, we demonstrate in astrocytic cells that its synthesis, phosphorylation by Protein Kinase C-ε on Ser2808 (a residue adjacent to a nuclear localization sequence), and nuclear import are cell cycle-dependent, being maximal at G2. During mitosis, neurofibromin is an integral part of the spindle, while its depletion leads to aberrant chromosome congression, possibly explaining the development of chromosomal instability in Neurofibromatosis type-1. Read the Editorial Highlight for this article on page 11. Cover Image for this issue: doi: 10.1111/jnc.13300.
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Affiliation(s)
- Xeni Koliou
- Basic Research Center, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Constantinos Fedonidis
- Basic Research Center, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Theodora Kalpachidou
- Basic Research Center, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Dimitra Mangoura
- Basic Research Center, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
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In vitro modeling of hyperpigmentation associated to neurofibromatosis type 1 using melanocytes derived from human embryonic stem cells. Proc Natl Acad Sci U S A 2015; 112:9034-9. [PMID: 26150484 DOI: 10.1073/pnas.1501032112] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
"Café-au-lait" macules (CALMs) and overall skin hyperpigmentation are early hallmarks of neurofibromatosis type 1 (NF1). One of the most frequent monogenic diseases, NF1 has subsequently been characterized with numerous benign Schwann cell-derived tumors. It is well established that neurofibromin, the NF1 gene product, is an antioncogene that down-regulates the RAS oncogene. In contrast, the molecular mechanisms associated with alteration of skin pigmentation have remained elusive. We have reassessed this issue by differentiating human embryonic stem cells into melanocytes. In the present study, we demonstrate that NF1 melanocytes reproduce the hyperpigmentation phenotype in vitro, and further characterize the link between loss of heterozygosity and the typical CALMs that appear over the general hyperpigmentation. Molecular mechanisms associated with these pathological phenotypes correlate with an increased activity of cAMP-mediated PKA and ERK1/2 signaling pathways, leading to overexpression of the transcription factor MITF and of the melanogenic enzymes tyrosinase and dopachrome tautomerase, all major players in melanogenesis. Finally, the hyperpigmentation phenotype can be rescued using specific inhibitors of these signaling pathways. These results open avenues for deciphering the pathological mechanisms involved in pigmentation diseases, and provide a robust assay for the development of new strategies for treating these diseases.
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