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Zhang K, Yao H, Yang J, Jia T, Shan Q, Li D, Li M, Gan L, Wang X, Dong Y. Analysis of clinical characteristics and histopathological transcription in 40 patients afflicted by epilepsy stemming from focal cortical dysplasia. Epilepsia Open 2024; 9:981-995. [PMID: 38491953 PMCID: PMC11145614 DOI: 10.1002/epi4.12928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 02/26/2024] [Accepted: 03/06/2024] [Indexed: 03/18/2024] Open
Abstract
OBJECTIVE This study aims to comprehensively analyze the clinical characteristics and identify the differentially expressed genes associated with drug-resistant epilepsy (DRE) in patients with focal cortical dysplasia (FCD). METHODS A retrospective investigation was conducted from July 2019 to June 2022, involving 40 pediatric cases of DRE linked to FCD. Subsequent follow-ups were done to assess post-surgical outcomes. Transcriptomic sequencing and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to examine differential gene expression between the FCD and control groups. RESULTS Among the 40 patients included in the study, focal to bilateral tonic-clonic seizures (13/40, 32.50%) and epileptic spasms (9/40, 22.50%) were the predominant seizure types. Magnetic resonance imaging (MRI) showed frequent involvement of the frontal (22/40, 55%) and temporal lobes (12/40, 30%). In cases with negative MRI results (13/13, 100%), positron emission tomography/computed tomography (PET-CT) scans revealed hypometabolic lesions. Fused MRI/PET-CT images demonstrated lesion reduction in 40.74% (11/27) of cases compared with PET-CT alone, while 59.26% (16/27) yielded results consistent with PET-CT findings. FCD type II was identified in 26 cases, and FCD type I in 13 cases. At the last follow-up, 38 patients were prescribed an average of 1.27 ± 1.05 anti-seizure medications (ASMs), with two patients discontinuing treatment. After a postoperative follow-up period of 23.50 months, 75% (30/40) of patients achieved Engel class I outcome. Transcriptomic sequencing and qRT-PCR analysis identified several genes primarily associated with cilia, including CFAP47, CFAP126, JHY, RSPH4A, and SPAG1. SIGNIFICANCE This study highlights focal to bilateral tonic-clonic seizures as the most common seizure type in patients with DRE due to FCD. Surgical intervention primarily targeted lesions in the frontal and temporal lobes. Patients with FCD-related DRE showed a promising prognosis for seizure control post-surgery. The identified genes, including CFAP47, CFAP126, JHY, RSPH4A, and SPAG1, could serve as potential biomarkers for FCD. PLAIN LANGUAGE SUMMARY This study aimed to comprehensively evaluate the clinical data of individuals affected by focal cortical dysplasia and analyze transcriptomic data from brain tissues. We found that focal to bilateral tonic-clonic seizures were the most prevalent seizure type in patients with drug-resistant epilepsy. In cases treated surgically, the frontal and temporal lobes were the primary sites of the lesions. Moreover, patients with focal cortical dysplasia-induced drug-resistant epilepsy exhibited a favorable prognosis for seizure control after surgery. CFAP47, CFAP126, JHY, RSPH4A, and SPAG1 have emerged as potential pathogenic genes for the development of focal cortical dysplasia.
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Affiliation(s)
- Ke Zhang
- Department of PediatricsThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Academy of Medical SciencesZhengzhou UniversityZhengzhouChina
| | - He Yao
- Department of PediatricsThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Academy of Medical SciencesZhengzhou UniversityZhengzhouChina
| | - Jixue Yang
- Department of Pediatric NeurosurgeryThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Tianming Jia
- Department of PediatricsThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Qiao Shan
- Department of Pediatric NeurosurgeryThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Dongming Li
- Department of Pediatric NeurosurgeryThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Mengchun Li
- Department of PediatricsThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Ling Gan
- Department of PediatricsThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Xinjun Wang
- Department of Pediatric NeurosurgeryThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Yan Dong
- Department of PediatricsThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Henan Key Laboratory of Child Brain Injury and Henan Pediatric Clinical Research CenterThe Third Affiliated Hospital and Institute of NeuroscienceZhengzhouChina
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Costanza M, Ciotti A, Consonni A, Cipelletti B, Cattalini A, Cagnoli C, Baggi F, de Curtis M, Colciaghi F. CNS autoimmune response in the MAM/pilocarpine rat model of epileptogenic cortical malformation. Proc Natl Acad Sci U S A 2024; 121:e2319607121. [PMID: 38635635 PMCID: PMC11047071 DOI: 10.1073/pnas.2319607121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 03/14/2024] [Indexed: 04/20/2024] Open
Abstract
The development of seizures in epilepsy syndromes associated with malformations of cortical development (MCDs) has traditionally been attributed to intrinsic cortical alterations resulting from abnormal network excitability. However, recent analyses at single-cell resolution of human brain samples from MCD patients have indicated the possible involvement of adaptive immunity in the pathogenesis of these disorders. By exploiting the MethylAzoxyMethanol (MAM)/pilocarpine (MP) rat model of drug-resistant epilepsy associated with MCD, we show here that the occurrence of status epilepticus and subsequent spontaneous recurrent seizures in the malformed, but not in the normal brain, are associated with the outbreak of a destructive autoimmune response with encephalitis-like features, involving components of both cell-mediated and humoral immune responses. The MP brain is characterized by blood-brain barrier dysfunction, marked and persisting CD8+ T cell invasion of the brain parenchyma, meningeal B cell accumulation, and complement-dependent cytotoxicity mediated by antineuronal antibodies. Furthermore, the therapeutic treatment of MP rats with the immunomodulatory drug fingolimod promotes both antiepileptogenic and neuroprotective effects. Collectively, these data show that the MP rat could serve as a translational model of epileptogenic cortical malformations associated with a central nervous system autoimmune response. This work indicates that a preexisting brain maldevelopment predisposes to a secondary autoimmune response, which acts as a precipitating factor for epilepsy and suggests immune intervention as a therapeutic option to be further explored in epileptic syndromes associated with MCDs.
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Affiliation(s)
- Massimo Costanza
- Neuro-Oncology Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan20133, Italy
| | - Arianna Ciotti
- Epilepsy Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan20133, Italy
| | - Alessandra Consonni
- Neuroimmunology Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan20133, Italy
| | - Barbara Cipelletti
- Epilepsy Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan20133, Italy
| | - Alessandro Cattalini
- Epilepsy Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan20133, Italy
| | - Cinzia Cagnoli
- Epilepsy Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan20133, Italy
| | - Fulvio Baggi
- Neuroimmunology Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan20133, Italy
| | - Marco de Curtis
- Epilepsy Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan20133, Italy
| | - Francesca Colciaghi
- Epilepsy Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan20133, Italy
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Gooley S, Perucca P, Tubb C, Hildebrand MS, Berkovic SF. Somatic mosaicism in focal epilepsies. Curr Opin Neurol 2024; 37:105-114. [PMID: 38235675 DOI: 10.1097/wco.0000000000001244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
PURPOSE OF REVIEW Over the past decade, it has become clear that brain somatic mosaicism is an important contributor to many focal epilepsies. The number of cases and the range of underlying pathologies with somatic mosaicism are rapidly increasing. This growth in somatic variant discovery is revealing dysfunction in distinct molecular pathways in different focal epilepsies. RECENT FINDINGS We briefly summarize the current diagnostic yield of pathogenic somatic variants across all types of focal epilepsy where somatic mosaicism has been implicated and outline the specific molecular pathways affected by these variants. We will highlight the recent findings that have increased diagnostic yields such as the discovery of pathogenic somatic variants in novel genes, and new techniques that allow the discovery of somatic variants at much lower variant allele fractions. SUMMARY A major focus will be on the emerging evidence that somatic mosaicism may contribute to some of the more common focal epilepsies such as temporal lobe epilepsy with hippocampal sclerosis, which could lead to it being re-conceptualized as a genetic disorder.
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Affiliation(s)
- Samuel Gooley
- Epilepsy Research Centre, Department of Medicine, University of Melbourne
- Bladin-Berkovic Comprehensive Epilepsy Program, Department of Neurology, Austin Health, Heidelberg
| | - Piero Perucca
- Epilepsy Research Centre, Department of Medicine, University of Melbourne
- Bladin-Berkovic Comprehensive Epilepsy Program, Department of Neurology, Austin Health, Heidelberg
- Department of Neuroscience, Central Clinical School, Monash University
- Department of Neurology, Alfred Health, Melbourne
- Department of Neurology, The Royal Melbourne Hospital
| | - Caitlin Tubb
- Epilepsy Research Centre, Department of Medicine, University of Melbourne
| | - Michael S Hildebrand
- Epilepsy Research Centre, Department of Medicine, University of Melbourne
- Neuroscience Group, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Samuel F Berkovic
- Epilepsy Research Centre, Department of Medicine, University of Melbourne
- Bladin-Berkovic Comprehensive Epilepsy Program, Department of Neurology, Austin Health, Heidelberg
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Ferri L, Menghi V, Licchetta L, Dimartino P, Minardi R, Davì C, Di Vito L, Cifaldi E, Zenesini C, Gozzo F, Pelliccia V, Mariani V, de Spelorzi YCC, Gustincich S, Seri M, Tassi L, Pippucci T, Bisulli F. Detection of somatic and germline pathogenic variants in adult cohort of drug-resistant focal epilepsies. Epilepsy Behav 2024; 153:109716. [PMID: 38508103 DOI: 10.1016/j.yebeh.2024.109716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 02/20/2024] [Accepted: 02/21/2024] [Indexed: 03/22/2024]
Abstract
OBJECTIVE This study investigates the prevalence of pathogenic variants in the mechanistic target of rapamycin (mTOR) pathway in surgical specimens of malformations of cortical development (MCDs) and cases with negative histology. The study also aims to evaluate the predictive value of genotype-histotype findings on the surgical outcome. METHODS The study included patients with drug-resistant focal epilepsy who underwent epilepsy surgery. Cases were selected based on histopathological diagnosis, focusing on MCDs and negative findings. We included brain tissues both as formalin-fixed, paraffin-embedded (FFPE) or fresh frozen (FF) samples. Single-molecule molecular inversion probes (smMIPs) analysis was conducted, targeting the MTOR gene in FFPE samples and 10 genes within the mTOR pathway in FF samples. Correlations between genotype-histotype and surgical outcome were examined. RESULTS We included 78 patients for whom we obtained 28 FFPE samples and 50 FF tissues. Seventeen pathogenic variants (22 %) were identified and validated, with 13 being somatic within the MTOR gene and 4 germlines (2 DEPDC5, 1 TSC1, 1 TSC2). Pathogenic variants in mTOR pathway genes were exclusively found in FCDII and TSC cases, with a significant association between FCD type IIb and MTOR genotype (P = 0.003). Patients carrying mutations had a slightly better surgical outcome than the overall cohort, however it results not significant. The FCDII diagnosed cases more frequently had normal neuropsychological test, a higher incidence of auras, fewer multiple seizure types, lower occurrence of seizures with awareness impairment, less ictal automatisms, fewer Stereo-EEG investigations, and a longer period long-life of seizure freedom before surgery. SIGNIFICANCE This study confirms that somatic MTOR variants represent the primary genetic alteration detected in brain specimens from FCDII/TSC cases, while germline DEPDC5, TSC1/TSC2 variants are relatively rare. Systematic screening for these mutations in surgically treated patients' brain specimens can aid histopathological diagnoses and serve as a biomarker for positive surgical outcomes. Certain clinical features associated with pathogenic variants in mTOR pathway genes may suggest a genetic etiology in FCDII patients.
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Affiliation(s)
- L Ferri
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Epilepsy Center (full member of the European Reference Network EpiCARE), Via Altura 3, Bologna 40139, Italy; Department of Biomedical and NeuroMotor Sciences, University of Bologna, Via Massarenti, 9 - Pad. 11 - 40138 Bologna, Italy
| | - V Menghi
- Department of Biomedical and NeuroMotor Sciences, University of Bologna, Via Massarenti, 9 - Pad. 11 - 40138 Bologna, Italy; Neurology Unit, Rimini "Infermi" Hospital-AUSL Romagna, Rimini, Italy
| | - L Licchetta
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Epilepsy Center (full member of the European Reference Network EpiCARE), Via Altura 3, Bologna 40139, Italy
| | - P Dimartino
- Department of Medical and Surgical Sciences, University of Bologna, Via Massarenti, 9 - Pad. 11 - 40138 Bologna, Italy
| | - R Minardi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Epilepsy Center (full member of the European Reference Network EpiCARE), Via Altura 3, Bologna 40139, Italy
| | - C Davì
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Epilepsy Center (full member of the European Reference Network EpiCARE), Via Altura 3, Bologna 40139, Italy
| | - L Di Vito
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Epilepsy Center (full member of the European Reference Network EpiCARE), Via Altura 3, Bologna 40139, Italy
| | - E Cifaldi
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy; Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - C Zenesini
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Epilepsy Center (full member of the European Reference Network EpiCARE), Via Altura 3, Bologna 40139, Italy
| | - F Gozzo
- Claudio Munari Epilepsy Surgery Center, Niguarda Hospital, Milano, Italy
| | - V Pelliccia
- Claudio Munari Epilepsy Surgery Center, Niguarda Hospital, Milano, Italy
| | - V Mariani
- Neurology and Stroke Unit, ASST Santi Paolo e Carlo, Presidio San Carlo Borromeo, Milano, Italy
| | - Y C C de Spelorzi
- Genomics Facility, Istituto Italiano di Tecnologia (IIT), Genova, Italy
| | - S Gustincich
- Center for Human Technologies, Non-coding RNAs and RNA-based Therapeutics, Istituto Italiano di Tecnologia (IIT), Genova, Italy
| | - M Seri
- Department of Biomedical and NeuroMotor Sciences, University of Bologna, Via Massarenti, 9 - Pad. 11 - 40138 Bologna, Italy; IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - L Tassi
- Claudio Munari Epilepsy Surgery Center, Niguarda Hospital, Milano, Italy
| | - T Pippucci
- Department of Biomedical and NeuroMotor Sciences, University of Bologna, Via Massarenti, 9 - Pad. 11 - 40138 Bologna, Italy; IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - F Bisulli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Epilepsy Center (full member of the European Reference Network EpiCARE), Via Altura 3, Bologna 40139, Italy; Department of Biomedical and NeuroMotor Sciences, University of Bologna, Via Massarenti, 9 - Pad. 11 - 40138 Bologna, Italy.
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Nguyen LH, Xu Y, Nair M, Bordey A. The mTOR pathway genes MTOR, Rheb, Depdc5, Pten, and Tsc1 have convergent and divergent impacts on cortical neuron development and function. eLife 2024; 12:RP91010. [PMID: 38411613 PMCID: PMC10942629 DOI: 10.7554/elife.91010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024] Open
Abstract
Brain somatic mutations in various components of the mTOR complex 1 (mTORC1) pathway have emerged as major causes of focal malformations of cortical development and intractable epilepsy. While these distinct gene mutations converge on excessive mTORC1 signaling and lead to common clinical manifestations, it remains unclear whether they cause similar cellular and synaptic disruptions underlying cortical network hyperexcitability. Here, we show that in utero activation of the mTORC1 activator genes, Rheb or MTOR, or biallelic inactivation of the mTORC1 repressor genes, Depdc5, Tsc1, or Pten in the mouse medial prefrontal cortex leads to shared alterations in pyramidal neuron morphology, positioning, and membrane excitability but different changes in excitatory synaptic transmission. Our findings suggest that, despite converging on mTORC1 signaling, mutations in different mTORC1 pathway genes differentially impact cortical excitatory synaptic activity, which may confer gene-specific mechanisms of hyperexcitability and responses to therapeutic intervention.
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Affiliation(s)
- Lena H Nguyen
- Department of Neuroscience, School of Behavioral and Brain Sciences, University of Texas at DallasRichardsonUnited States
- Departments of Neurosurgery and Cellular & Molecular Physiology, Wu Tsai Institute, Yale University School of MedicineNew HavenUnited States
| | - Youfen Xu
- Departments of Neurosurgery and Cellular & Molecular Physiology, Wu Tsai Institute, Yale University School of MedicineNew HavenUnited States
| | - Maanasi Nair
- Departments of Neurosurgery and Cellular & Molecular Physiology, Wu Tsai Institute, Yale University School of MedicineNew HavenUnited States
| | - Angelique Bordey
- Departments of Neurosurgery and Cellular & Molecular Physiology, Wu Tsai Institute, Yale University School of MedicineNew HavenUnited States
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Tobochnik S, Dorotan MKC, Ghosh HS, Lapinskas E, Vogelzang J, Reardon DA, Ligon KL, Bi WL, Smirnakis SM, Lee JW. Glioma genetic profiles associated with electrophysiologic hyperexcitability. Neuro Oncol 2024; 26:323-334. [PMID: 37713468 PMCID: PMC10836775 DOI: 10.1093/neuonc/noad176] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Indexed: 09/17/2023] Open
Abstract
BACKGROUND Distinct genetic alterations determine glioma aggressiveness, however, the diversity of somatic mutations contributing to peritumoral hyperexcitability and seizures over the course of the disease is uncertain. This study aimed to identify tumor somatic mutation profiles associated with clinically significant hyperexcitability. METHODS A single center cohort of adults with WHO grades 1-4 glioma and targeted exome sequencing (n = 1716) was analyzed and cross-referenced with a validated EEG database to identify the subset of individuals who underwent continuous EEG monitoring (n = 206). Hyperexcitability was defined by the presence of lateralized periodic discharges and/or electrographic seizures. Cross-validated discriminant analysis models trained exclusively on recurrent somatic mutations were used to identify variants associated with hyperexcitability. RESULTS The distribution of WHO grades and tumor mutational burdens were similar between patients with and without hyperexcitability. Discriminant analysis models classified the presence or absence of EEG hyperexcitability with an overall accuracy of 70.9%, regardless of IDH1 R132H inclusion. Predictive variants included nonsense mutations in ATRX and TP53, indel mutations in RBBP8 and CREBBP, and nonsynonymous missense mutations with predicted damaging consequences in EGFR, KRAS, PIK3CA, TP53, and USP28. This profile improved estimates of hyperexcitability in a multivariate analysis controlling for age, sex, tumor location, integrated pathologic diagnosis, recurrence status, and preoperative epilepsy. Predicted somatic mutation variants were over-represented in patients with hyperexcitability compared to individuals without hyperexcitability and those who did not undergo continuous EEG. CONCLUSION These findings implicate diverse glioma somatic mutations in cancer genes associated with peritumoral hyperexcitability. Tumor genetic profiling may facilitate glioma-related epilepsy prognostication and management.
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Affiliation(s)
- Steven Tobochnik
- Department of Neurology, VA Boston Healthcare System, Boston, Massachusetts, USA
- Department of Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | | | - Hia S Ghosh
- Department of Neurosurgery, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Emily Lapinskas
- Department of Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Jayne Vogelzang
- Department of Pathology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - David A Reardon
- Department of Medical Oncology, Center for Neuro-Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Keith L Ligon
- Department of Pathology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Wenya Linda Bi
- Department of Neurosurgery, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Stelios M Smirnakis
- Department of Neurology, VA Boston Healthcare System, Boston, Massachusetts, USA
- Department of Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Jong Woo Lee
- Department of Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA
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Phillips HW, D'Gama AM, Wang Y, Chahine Y, Chiu M, Swanson AC, Ahtam B, Bolton JB, Madsen JR, Lee EA, Prabhu SP, Lidov HG, Papadakis J, Huang AY, Poduri A, Stone SS, Walsh CA. Somatic Mosaicism in PIK3CA Variant Correlates With Stereoelectroencephalography-Derived Electrophysiology. Neurol Genet 2024; 10:e200117. [PMID: 38149038 PMCID: PMC10751024 DOI: 10.1212/nxg.0000000000200117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 10/20/2023] [Indexed: 12/28/2023]
Abstract
Objectives Brain-limited pathogenic somatic variants are associated with focal pediatric epilepsy, but reliance on resected brain tissue samples has limited our ability to correlate epileptiform activity with abnormal molecular pathology. We aimed to identify the pathogenic variant and map variant allele fractions (VAFs) across an abnormal region of epileptogenic brain in a patient who underwent stereoelectroencephalography (sEEG) and subsequent motor-sparing left frontal disconnection. Methods We extracted genomic DNA from peripheral blood, brain tissue resected from peri-sEEG electrode regions, and microbulk brain tissue adherent to sEEG electrodes. Samples were mapped based on an anatomic relationship with the presumed seizure onset zone (SOZ). We performed deep panel sequencing of amplified and unamplified DNA to identify pathogenic variants with subsequent orthogonal validation. Results We detect a pathogenic somatic PIK3CA variant, c.1624G>A (p.E542K), in the brain tissue samples, with VAF inversely correlated with distance from the SOZ. In addition, we identify this variant in amplified electrode-derived samples, albeit with lower VAFs. Discussion We demonstrate regional mosaicism across epileptogenic tissue, suggesting a correlation between variant burden and SOZ. We also validate a pathogenic variant from individual amplified sEEG electrode-derived brain specimens, although further optimization of techniques is required.
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Affiliation(s)
- H Westley Phillips
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Alissa M D'Gama
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Yilan Wang
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Yasmine Chahine
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Michelle Chiu
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Amanda C Swanson
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Banu Ahtam
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Jeffrey B Bolton
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Joseph R Madsen
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Eunjung A Lee
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Sanjay P Prabhu
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Hart G Lidov
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Joanna Papadakis
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - August Y Huang
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Annapurna Poduri
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Scellig S Stone
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
| | - Christopher A Walsh
- From the Department of Neurosurgery (H.W.P.), Stanford School of Medicine, Palo Alto, CA; Department of Neurosurgery (H.W.P., J.R.M., J.P., S.S.S.), Boston Children's Hospital, Harvard Medical School; Broad Institute of MIT and Harvard (H.W.P., Y.W., Y.C., E.A.L., A.Y.H., C.A.W.), Cambridge; Division of Genetics and Genomics (H.W.P., Y.W., E.A.L., A.Y.H., C.A.W.), Manton Center for Orphan Disease Research; Division of Newborn Medicine (A.M.D.G., B.A.), Department of Pediatrics; Epilepsy Genetics Program (A.M.D.G., J.B.B., A.P.), Department of Neurology; Department of Pediatrics (A.M.D.G., J.B.B., E.A.L., A.Y.H., C.A.W.), Harvard Medical School, Boston Children's Hospital; Program in Biological and Biomedical Sciences (Y.W.); Department of Neurology (M.C., J.B.B., A.P., C.A.W.), Boston Children's Hospital, Harvard Medical School; Translational Neuroscience Center (A.C.S.), Boston Children's Hospital; Department of Radiology (S.P.P.), Division of Neuroradiology; Department of Pathology (H.G.L.), Division of Neuropathology, Boston Children's Hospital, Harvard Medical School; and Howard Hughes Medical Institute (C.A.W.), Boston, MA
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Nguyen LH, Xu Y, Nair M, Bordey A. The mTOR pathway genes mTOR, Rheb, Depdc5, Pten, and Tsc1 have convergent and divergent impacts on cortical neuron development and function. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.08.11.553034. [PMID: 37609221 PMCID: PMC10441381 DOI: 10.1101/2023.08.11.553034] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Brain somatic mutations in various components of the mTOR complex 1 (mTORC1) pathway have emerged as major causes of focal malformations of cortical development and intractable epilepsy. While these distinct gene mutations converge on excessive mTORC1 signaling and lead to common clinical manifestations, it remains unclear whether they cause similar cellular and synaptic disruptions underlying cortical network hyperexcitability. Here, we show that in utero activation of the mTORC1 activators, Rheb or mTOR, or biallelic inactivation of the mTORC1 repressors, Depdc5, Tsc1, or Pten in mouse medial prefrontal cortex leads to shared alterations in pyramidal neuron morphology, positioning, and membrane excitability but different changes in excitatory synaptic transmission. Our findings suggest that, despite converging on mTORC1 signaling, mutations in different mTORC1 pathway genes differentially impact cortical excitatory synaptic activity, which may confer gene-specific mechanisms of hyperexcitability and responses to therapeutic intervention.
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Affiliation(s)
- Lena H. Nguyen
- Department Neuroscience, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX 75080, USA
- Departments of Neurosurgery and Cellular & Molecular Physiology, Wu Tsai Institute, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Youfen Xu
- Departments of Neurosurgery and Cellular & Molecular Physiology, Wu Tsai Institute, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Maanasi Nair
- Departments of Neurosurgery and Cellular & Molecular Physiology, Wu Tsai Institute, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Angelique Bordey
- Departments of Neurosurgery and Cellular & Molecular Physiology, Wu Tsai Institute, Yale University School of Medicine, New Haven, CT 06510, USA
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Blümcke I. Neuropathology and epilepsy surgery - 2024 update. FREE NEUROPATHOLOGY 2024; 5:5-8. [PMID: 38532826 PMCID: PMC10964794 DOI: 10.17879/freeneuropathology-2024-5347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 03/11/2024] [Indexed: 03/28/2024]
Abstract
Neuropathology-based studies in neurosurgically resected brain tissue obtained from carefully examined patients with focal epilepsies remain a treasure box for excellent insights into human neuroscience, including avenues to better understand the neurobiology of human brain organization and neuronal hyperexcitability at the cellular level including glio-neuronal interaction. It also allows to translate results from animal models in order to develop personalized treatment strategies in the near future. A nice example of this is the discovery of a new disease entity in 2017, termed mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy or MOGHE, in the frontal lobe of young children with intractable seizures. In 2021, a brain somatic missense mutation of the galactose transporter SLC35A2 leading to altered glycosylation of lipoproteins in the Golgi apparatus was detected in 50 % of MOGHE samples. In 2023, the first clinical trial evaluated galactose supplementation in patients with histopathologically confirmed MOGHE carrying brain somatic SLC35A2 mutations that were not seizure free after surgery. The promising results of this pilot trial are an example of personalized medicine in the arena of epileptology. Besides this, neuropathological studies of epilepsy samples have revealed many other fascinating results for the main disease categories in focal epilepsies, such as the first deep-learning based classifier for Focal Cortical Dysplasia, or the genomic landscape of cortical malformations showing new candidate genes such as PTPN11, which is associated with ganglioglioma and adverse clinical outcome. This update will also ask why common pathogenic variants accumulate in certain brain regions, e.g., MTOR in the frontal lobe, and BRAF in the temporal lobe. Finally, I will highlight the ongoing discussion addressing commonalities between temporal lobe epilepsy and Alzheimer's disease, the impact of adult neurogenesis and gliogenesis for the initiation and progression of temporal lobe seizures in the human brain as well as the immunopathogenesis of glutamic acid decarboxylase antibody associated temporal lobe epilepsy as a meaningful disease entity. This review will update the reader on some of these fascinating publications from 2022 and 2023 which were selected carefully, yet subjectively, by the author.
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Affiliation(s)
- Ingmar Blümcke
- Department of Neuropathology, University Hospital Erlangen, Germany
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Maury EA, Walsh CA, Kahle KT. Neurosurgery elucidates somatic mutations. Science 2023; 382:1360-1362. [PMID: 38127765 DOI: 10.1126/science.adj2244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Surgical innovation is helping to identify roles for somatic mutations in brain disorders.
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Affiliation(s)
- Eduardo A Maury
- Division of Genetics and Genomics, Manton Center for Orphan Disease, Boston Children's Hospital, Boston, MA, USA
- Harvard/MIT MD-PhD Program, Harvard Medical School, Boston, MA, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Christopher A Walsh
- Division of Genetics and Genomics, Manton Center for Orphan Disease, Boston Children's Hospital, Boston, MA, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA
| | - Kristopher T Kahle
- Division of Genetics and Genomics, Manton Center for Orphan Disease, Boston Children's Hospital, Boston, MA, USA
- Program in Neuroscience, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Neurosurgery, Boston Children's Hospital, Boston, MA, USA
- Department of Neurosurgery, Massachusetts General Hospital, Boston, MA, USA
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11
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Akula SK, Exposito-Alonso D, Walsh CA. Shaping the brain: The emergence of cortical structure and folding. Dev Cell 2023; 58:2836-2849. [PMID: 38113850 PMCID: PMC10793202 DOI: 10.1016/j.devcel.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 04/08/2023] [Accepted: 11/10/2023] [Indexed: 12/21/2023]
Abstract
The cerebral cortex-the brain's covering and largest region-has increased in size and complexity in humans and supports higher cognitive functions such as language and abstract thinking. There is a growing understanding of the human cerebral cortex, including the diversity and number of cell types that it contains, as well as of the developmental mechanisms that shape cortical structure and organization. In this review, we discuss recent progress in our understanding of molecular and cellular processes, as well as mechanical forces, that regulate the folding of the cerebral cortex. Advances in human genetics, coupled with experimental modeling in gyrencephalic species, have provided insights into the central role of cortical progenitors in the gyrification and evolutionary expansion of the cerebral cortex. These studies are essential for understanding the emergence of structural and functional organization during cortical development and the pathogenesis of neurodevelopmental disorders associated with cortical malformations.
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Affiliation(s)
- Shyam K Akula
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, USA; Departments of Pediatrics and Neurology, Harvard Medical School, Boston, MA, USA; Allen Discovery Center for Human Brain Evolution, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA; Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
| | - David Exposito-Alonso
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, USA; Departments of Pediatrics and Neurology, Harvard Medical School, Boston, MA, USA; Allen Discovery Center for Human Brain Evolution, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA; Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
| | - Christopher A Walsh
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, USA; Departments of Pediatrics and Neurology, Harvard Medical School, Boston, MA, USA; Allen Discovery Center for Human Brain Evolution, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA; Howard Hughes Medical Institute, Chevy Chase, Maryland, USA.
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Zhou Z, Kim J, Huang AY, Nolan M, Park J, Doan R, Shin T, Miller MB, Chhouk B, Morillo K, Yeh RC, Kenny C, Neil JE, Lee CZ, Ohkubo T, Ravits J, Ansorge O, Ostrow LW, Lagier-Tourenne C, Lee EA, Walsh CA. Somatic Mosaicism in Amyotrophic Lateral Sclerosis and Frontotemporal Dementia Reveals Widespread Degeneration from Focal Mutations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.30.569436. [PMID: 38077003 PMCID: PMC10705414 DOI: 10.1101/2023.11.30.569436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
Although mutations in dozens of genes have been implicated in familial forms of amyotrophic lateral sclerosis (fALS) and frontotemporal degeneration (fFTD), most cases of these conditions are sporadic (sALS and sFTD), with no family history, and their etiology remains obscure. We tested the hypothesis that somatic mosaic mutations, present in some but not all cells, might contribute in these cases, by performing ultra-deep, targeted sequencing of 88 genes associated with neurodegenerative diseases in postmortem brain and spinal cord samples from 404 individuals with sALS or sFTD and 144 controls. Known pathogenic germline mutations were found in 20.6% of ALS, and 26.5% of FTD cases. Predicted pathogenic somatic mutations in ALS/FTD genes were observed in 2.7% of sALS and sFTD cases that did not carry known pathogenic or novel germline mutations. Somatic mutations showed low variant allele fraction (typically <2%) and were often restricted to the region of initial discovery, preventing detection through genetic screening in peripheral tissues. Damaging somatic mutations were preferentially enriched in primary motor cortex of sALS and prefrontal cortex of sFTD, mirroring regions most severely affected in each disease. Somatic mutation analysis of bulk RNA-seq data from brain and spinal cord from an additional 143 sALS cases and 23 controls confirmed an overall enrichment of somatic mutations in sALS. Two adult sALS cases were identified bearing pathogenic somatic mutations in DYNC1H1 and LMNA, two genes associated with pediatric motor neuron degeneration. Our study suggests that somatic mutations in fALS/fFTD genes, and in genes associated with more severe diseases in the germline state, contribute to sALS and sFTD, and that mosaic mutations in a small fraction of cells in focal regions of the nervous system can ultimately result in widespread degeneration.
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Affiliation(s)
- Zinan Zhou
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Junho Kim
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
- Department of Biological Sciences, Sungkyunkwan University, Suwon, South Korea
| | - August Yue Huang
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Matthew Nolan
- Department of Neurology, The Sean M. Healey and AMG Center for ALS at Mass General, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Junseok Park
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Ryan Doan
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Taehwan Shin
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Michael B. Miller
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Brian Chhouk
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Katherine Morillo
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Rebecca C. Yeh
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Connor Kenny
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Jennifer E. Neil
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, MA, USA
| | - Chao-Zong Lee
- Department of Neurology, The Sean M. Healey and AMG Center for ALS at Mass General, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Takuya Ohkubo
- Department of Neurology, Yokohama City Minato Red Cross Hospital, Yokohama, Kanagawa, Japan
- Department of Neurosciences, School of Medicine, University of California at San Diego, La Jolla, CA, USA
| | - John Ravits
- Department of Neurosciences, School of Medicine, University of California at San Diego, La Jolla, CA, USA
| | - Olaf Ansorge
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, Oxfordshire, UK
| | - Lyle W. Ostrow
- Department of Neurology, Lewis Katz School of Medicine at Temple University, Philadelphia, USA
| | - Clotilde Lagier-Tourenne
- Department of Neurology, The Sean M. Healey and AMG Center for ALS at Mass General, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Eunjung Alice Lee
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Christopher A. Walsh
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, MA, USA
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, MA, USA
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Cohen NT, Xie H, Gholipour T, Gaillard WD. A scoping review of the functional magnetic resonance imaging-based functional connectivity of focal cortical dysplasia-related epilepsy. Epilepsia 2023; 64:3130-3142. [PMID: 37731142 DOI: 10.1111/epi.17775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 09/17/2023] [Accepted: 09/18/2023] [Indexed: 09/22/2023]
Abstract
Focal cortical dysplasia (FCD) is the most frequent etiology of operable pharmacoresistant epilepsy in children. There is burgeoning evidence that FCD-related epilepsy is a disorder that involves distributed brain networks. Functional magnetic resonance imaging (fMRI) is a tool that allows one to infer neuronal activity and to noninvasively map whole-brain functional networks. Despite its relatively widespread availability at most epilepsy centers, the clinical application of fMRI remains mostly task-based in epilepsy. Another approach is to map and characterize cortical functional networks of individuals using resting state fMRI (rsfMRI). The focus of this scoping review is to summarize the evidence to date of investigations of the network basis of FCD-related epilepsy, and to highlight numerous potential future applications of rsfMRI in the exploration of diagnostic and therapeutic strategies for FCD-related epilepsy. There are numerous studies demonstrating a global disruption of cortical functional networks in FCD-related epilepsy. The underlying pathological subtypes of FCD influence overall functional network patterns. There is evidence that cortical functional network mapping may help to predict postsurgical seizure outcomes, highlighting the translational potential of these findings. Additionally, several studies emphasize the important effect of FCD interaction with cortical networks and the expression of epilepsy and its comorbidities.
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Affiliation(s)
- Nathan T Cohen
- Center for Neuroscience Research, Children's National Hospital, George Washington University School of Medicine, Washington, District of Columbia, USA
- Department of Neurology, Children's National Hospital, George Washington University School of Medicine, Washington, District of Columbia, USA
| | - Hua Xie
- Center for Neuroscience Research, Children's National Hospital, George Washington University School of Medicine, Washington, District of Columbia, USA
- Department of Neurology, Children's National Hospital, George Washington University School of Medicine, Washington, District of Columbia, USA
| | - Taha Gholipour
- Center for Neuroscience Research, Children's National Hospital, George Washington University School of Medicine, Washington, District of Columbia, USA
- Department of Neurology, George Washington University Epilepsy Center, Washington, District of Columbia, USA
| | - William D Gaillard
- Center for Neuroscience Research, Children's National Hospital, George Washington University School of Medicine, Washington, District of Columbia, USA
- Department of Neurology, Children's National Hospital, George Washington University School of Medicine, Washington, District of Columbia, USA
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14
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Krochmalnek E, Accogli A, St-Onge J, Addour-Boudrahem N, Prakash G, Kim SH, Brunette-Clement T, Alhajaj G, Mougharbel L, Bruneau E, Myers KA, Dubeau F, Karamchandani J, Farmer JP, Atkinson J, Hall J, Chantal Poulin C, Rosenblatt B, Lafond-Lapalme J, Weil A, Fallet-Bianco C, Albrecht S, Sonenberg N, Riviere JB, Dudley RW, Srour M. mTOR Pathway Somatic Pathogenic Variants in Focal Malformations of Cortical Development: Novel Variants, Topographic Mapping, and Clinical Outcomes. Neurol Genet 2023; 9:e200103. [PMID: 37900581 PMCID: PMC10602370 DOI: 10.1212/nxg.0000000000200103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 09/06/2023] [Indexed: 10/31/2023]
Abstract
Background and Objectives Somatic and germline pathogenic variants in genes of the mammalian target of rapamycin (mTOR) signaling pathway are a common mechanism underlying a subset of focal malformations of cortical development (FMCDs) referred to as mTORopathies, which include focal cortical dysplasia (FCD) type II, subtypes of polymicrogyria, and hemimegalencephaly. Our objective is to screen resected FMCD specimens with mTORopathy features on histology for causal somatic variants in mTOR pathway genes, describe novel pathogenic variants, and examine the variant distribution in relation to neuroimaging, histopathologic classification, and clinical outcomes. Methods We performed ultra-deep sequencing using a custom HaloPlexHS Target Enrichment kit in DNA from 21 resected fresh-frozen histologically confirmed FCD type II, tuberous sclerosis complex, or hemimegalencephaly specimens. We mapped the variant alternative allele frequency (AAF) across the resected brain using targeted ultra-deep sequencing in multiple formalin-fixed paraffin-embedded tissue blocks. We also functionally validated 2 candidate somatic MTOR variants and performed targeted RNA sequencing to validate a splicing defect associated with a novel DEPDC5 variant. Results We identified causal mTOR pathway gene variants in 66.7% (14/21) of patients, of which 13 were somatic with AAF ranging between 0.6% and 12.0%. Moreover, the AAF did not predict balloon cell presence. Favorable seizure outcomes were associated with genetically clear resection borders. Individuals in whom a causal somatic variant was undetected had excellent postsurgical outcomes. In addition, we demonstrate pathogenicity of the novel c.4373_4375dupATG and candidate c.7499T>A MTOR variants in vitro. We also identified a novel germline aberrant splice site variant in DEPDC5 (c.2802-1G>C). Discussion The AAF of somatic pathogenic variants correlated with the topographic distribution, histopathology, and postsurgical outcomes. Moreover, cortical regions with absent histologic FCD features had negligible or undetectable pathogenic variant loads. By contrast, specimens with frank histologic abnormalities had detectable pathogenic variant loads, which raises important questions as to whether there is a tolerable variant threshold and whether surgical margins should be clean, as performed in tumor resections. In addition, we describe 2 novel pathogenic variants, expanding the mTORopathy genetic spectrum. Although most pathogenic somatic variants are located at mutation hotspots, screening the full-coding gene sequence remains necessary in a subset of patients.
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Affiliation(s)
- Eric Krochmalnek
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Andrea Accogli
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Judith St-Onge
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Nassima Addour-Boudrahem
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Gyan Prakash
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Sung-Hoon Kim
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Tristan Brunette-Clement
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Ghadd Alhajaj
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Lina Mougharbel
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Elena Bruneau
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Kenneth A Myers
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Francois Dubeau
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Jason Karamchandani
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Jean-Pierre Farmer
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Jeffrey Atkinson
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Jeffrey Hall
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Chantal Chantal Poulin
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Bernard Rosenblatt
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Joel Lafond-Lapalme
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Alexander Weil
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Catherine Fallet-Bianco
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Steffen Albrecht
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Nahum Sonenberg
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Jean-Baptiste Riviere
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Roy W Dudley
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
| | - Myriam Srour
- From the Research Institute of the McGill University Health Centre (E.K., J.S.-O., N.A.-B., L.M., E.B., K.A.M., J.L.-L., J.-B.R., R.W.D., M.S.); Integrated Program in Neuroscience (E.K.), McGill University; Department of Specialized Medicine (A.A.), McGill University Health Centre; Department of Human Genetics (A.A., J.-B.R.), Faculty of Medicine; Goodman Cancer Centre (G.P., S.-H.K., N.S.), Department of Biochemistry, McGill University; Department of Pediatric Neurosurgery (T.B.-C., A.W.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal; Division of Pediatric Neurology (G.A., K.A.M., C.C.P., M.S.), Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Pediatrics (G.A.), Unaizah College of Medicine and Medical Sciences, Qassim University, Saudi Arabia; Department of Neurology and Neurosurgery (K.A.M., F.D., J.H., C.C.P., M.S.), McGill University Health Centre; Department of Pathology (J.K., S.A.), McGill University; Division of Neurosurgery (J.-P.F., J.A., R.W.D.), Department of Pediatric Surgery, McGill University Health Center; McGill University (B.R.); Department of Pathology (C.F.-B.), Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Quebec, Canada
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15
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Honke J, Hoffmann L, Coras R, Kobow K, Leu C, Pieper T, Hartlieb T, Bien CG, Woermann F, Cloppenborg T, Kalbhenn T, Gaballa A, Hamer H, Brandner S, Rössler K, Dörfler A, Rampp S, Lemke JR, Baldassari S, Baulac S, Lal D, Nürnberg P, Blümcke I. Deep histopathology genotype-phenotype analysis of focal cortical dysplasia type II differentiates between the GATOR1-altered autophagocytic subtype IIa and MTOR-altered migration deficient subtype IIb. Acta Neuropathol Commun 2023; 11:179. [PMID: 37946310 PMCID: PMC10633947 DOI: 10.1186/s40478-023-01675-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 10/21/2023] [Indexed: 11/12/2023] Open
Abstract
Focal cortical dysplasia type II (FCDII) is the most common cause of drug-resistant focal epilepsy in children. Herein, we performed a deep histopathology-based genotype-phenotype analysis to further elucidate the clinico-pathological and genetic presentation of FCDIIa compared to FCDIIb. Seventeen individuals with histopathologically confirmed diagnosis of FCD ILAE Type II and a pathogenic variant detected in brain derived DNA whole-exome sequencing or mTOR gene panel sequencing were included in this study. Clinical data were directly available from each contributing centre. Histopathological analyses were performed from formalin-fixed, paraffin-embedded tissue samples using haematoxylin-eosin and immunohistochemistry for NF-SMI32, NeuN, pS6, p62, and vimentin. Ten individuals carried loss-of-function variants in the GATOR1 complex encoding genes DEPDC5 (n = 7) and NPRL3 (n = 3), or gain-of-function variants in MTOR (n = 7). Whereas individuals with GATOR1 variants only presented with FCDIIa, i.e., lack of balloon cells, individuals with MTOR variants presented with both histopathology subtypes, FCDIIa and FCDIIb. Interestingly, 50% of GATOR1-positive cases showed a unique and predominantly vacuolizing phenotype with p62 immunofluorescent aggregates in autophagosomes. All cases with GATOR1 alterations had neurosurgery in the frontal lobe and the majority was confined to the cortical ribbon not affecting the white matter. This pattern was reflected by subtle or negative MRI findings in seven individuals with GATOR1 variants. Nonetheless, all individuals were seizure-free after surgery except four individuals carrying a DEPDC5 variant. We describe a yet underrecognized genotype-phenotype correlation of GATOR1 variants with FCDIIa in the frontal lobe. These lesions were histopathologically characterized by abnormally vacuolizing cells suggestive of an autophagy-altered phenotype. In contrast, individuals with FCDIIb and brain somatic MTOR variants showed larger lesions on MRI including the white matter, suggesting compromised neural cell migration.
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Affiliation(s)
- Jonas Honke
- Department of Neuropathology, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
- Partner of the European Reference Network (ERN) EpiCARE, Barcelona, Spain
| | - Lucas Hoffmann
- Department of Neuropathology, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
- Partner of the European Reference Network (ERN) EpiCARE, Barcelona, Spain
| | - Roland Coras
- Department of Neuropathology, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
- Partner of the European Reference Network (ERN) EpiCARE, Barcelona, Spain
| | - Katja Kobow
- Department of Neuropathology, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
- Partner of the European Reference Network (ERN) EpiCARE, Barcelona, Spain
| | - Costin Leu
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
- Charles Shor Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, USA
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London, UK
- Department of Neurology, McGovern Medical School, UTHealth Houston, University of Texas, Houston, USA
| | - Tom Pieper
- Center for Pediatric Neurology, Neurorehabilitation, and Epileptology, Schoen-Clinic, Vogtareuth, Germany
| | - Till Hartlieb
- Center for Pediatric Neurology, Neurorehabilitation, and Epileptology, Schoen-Clinic, Vogtareuth, Germany
- Research Institute for Rehabilitation, Transition, and Palliation, Paracelsus Medical University, Salzburg, Austria
| | - Christian G Bien
- Department of Epileptology (Krankenhaus Mara), Medical School, Bielefeld University, Bielefeld, Germany
| | - Friedrich Woermann
- Department of Epileptology (Krankenhaus Mara), Medical School, Bielefeld University, Bielefeld, Germany
| | - Thomas Cloppenborg
- Department of Epileptology (Krankenhaus Mara), Medical School, Bielefeld University, Bielefeld, Germany
| | - Thilo Kalbhenn
- Department of Epileptology (Krankenhaus Mara), Medical School, Bielefeld University, Bielefeld, Germany
- Department of Neurosurgery (Evangelisches Klinikum Bethel), Medical School, Bielefeld University, Bielefeld, Germany
| | - Ahmed Gaballa
- Department of Epileptology (Krankenhaus Mara), Medical School, Bielefeld University, Bielefeld, Germany
| | - Hajo Hamer
- Partner of the European Reference Network (ERN) EpiCARE, Barcelona, Spain
- Epilepsy Center, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Sebastian Brandner
- Department of Neurosurgery, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Karl Rössler
- Department of Neurosurgery, Medical University of Vienna, Vienna General Hospital, Vienna, Austria
| | - Arnd Dörfler
- Department of Neuroradiology, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Stefan Rampp
- Department of Neurosurgery, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
- Department of Neuroradiology, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Johannes R Lemke
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
- Center for Rare Diseases, University of Leipzig Medical Center, Leipzig, Germany
| | - Sara Baldassari
- Inserm, CNRS, APHP, Institut du Cerveau - Paris Brain Institute - ICM, Hôpital de La Pitié Salpêtrière, Sorbonne Université, Paris, France
| | - Stéphanie Baulac
- Inserm, CNRS, APHP, Institut du Cerveau - Paris Brain Institute - ICM, Hôpital de La Pitié Salpêtrière, Sorbonne Université, Paris, France
| | - Dennis Lal
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
- Charles Shor Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, USA
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and M.I.T, Cambridge, MA, 02142, USA
- Cologne Center for Genomics (CCG), Medical Faculty of the University of Cologne, University Hospital of Cologne, 50931, Cologne, Germany
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London, UK
- Department of Neurology, McGovern Medical School, UTHealth Houston, University of Texas, Houston, USA
| | - Peter Nürnberg
- Cologne Center for Genomics (CCG), Medical Faculty of the University of Cologne, University Hospital of Cologne, 50931, Cologne, Germany
| | - Ingmar Blümcke
- Department of Neuropathology, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany.
- Partner of the European Reference Network (ERN) EpiCARE, Barcelona, Spain.
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and M.I.T, Cambridge, MA, 02142, USA.
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16
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Konopka G, Bhaduri A. Functional genomics and systems biology in human neuroscience. Nature 2023; 623:274-282. [PMID: 37938705 DOI: 10.1038/s41586-023-06686-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 09/27/2023] [Indexed: 11/09/2023]
Abstract
Neuroscience research has entered a phase of key discoveries in the realm of neurogenomics owing to strong financial and intellectual support for resource building and tool development. The previous challenge of tissue heterogeneity has been met with the application of techniques that can profile individual cells at scale. Moreover, the ability to perturb genes, gene regulatory elements and neuronal activity in a cell-type-specific manner has been integrated with gene expression studies to uncover the functional underpinnings of the genome at a systems level. Although these insights have necessarily been grounded in model systems, we now have the opportunity to apply these approaches in humans and in human tissue, thanks to advances in human genetics, brain imaging and tissue collection. We acknowledge that there will probably always be limits to the extent to which we can apply the genomic tools developed in model systems to human neuroscience; however, as we describe in this Perspective, the neuroscience field is now primed with an optimal foundation for tackling this ambitious challenge. The application of systems-level network analyses to these datasets will facilitate a deeper appreciation of human neurogenomics that cannot otherwise be achieved from directly observable phenomena.
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Affiliation(s)
- Genevieve Konopka
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX, USA.
- Peter O'Donnell Jr Brain Institute, UT Southwestern Medical Center, Dallas, TX, USA.
| | - Aparna Bhaduri
- Department of Biological Chemistry, University of California, Los Angeles, CA, USA.
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17
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Graham JH, Schlachetzki JCM, Yang X, Breuss MW. Genomic Mosaicism of the Brain: Origin, Impact, and Utility. Neurosci Bull 2023:10.1007/s12264-023-01124-8. [PMID: 37898991 DOI: 10.1007/s12264-023-01124-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 07/16/2023] [Indexed: 10/31/2023] Open
Abstract
Genomic mosaicism describes the phenomenon where some but not all cells within a tissue harbor unique genetic mutations. Traditionally, research focused on the impact of genomic mosaicism on clinical phenotype-motivated by its involvement in cancers and overgrowth syndromes. More recently, we increasingly shifted towards the plethora of neutral mosaic variants that can act as recorders of cellular lineage and environmental exposures. Here, we summarize the current state of the field of genomic mosaicism research with a special emphasis on our current understanding of this phenomenon in brain development and homeostasis. Although the field of genomic mosaicism has a rich history, technological advances in the last decade have changed our approaches and greatly improved our knowledge. We will provide current definitions and an overview of contemporary detection approaches for genomic mosaicism. Finally, we will discuss the impact and utility of genomic mosaicism.
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Affiliation(s)
- Jared H Graham
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado School of Medicine, Aurora, 80045-2581, CO, USA
| | - Johannes C M Schlachetzki
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, 92093-0021, San Diego, CA, USA
| | - Xiaoxu Yang
- Department of Neurosciences, University of California San Diego, La Jolla, 92093-0021, San Diego, CA, USA
- Rady Children's Institute for Genomic Medicine, San Diego, 92123, CA, USA
| | - Martin W Breuss
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado School of Medicine, Aurora, 80045-2581, CO, USA.
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18
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Du S, Zeng S, Song L, Ma H, Chen R, Luo J, Wang X, Ma T, Xu X, Sun H, Yi P, Guo J, Huang Y, Liu M, Wang T, Liao WP, Zhang L, Liu JY, Tang B. Functional characterization of novel NPRL3 mutations identified in three families with focal epilepsy. SCIENCE CHINA. LIFE SCIENCES 2023; 66:2152-2166. [PMID: 37071290 DOI: 10.1007/s11427-022-2313-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 03/01/2023] [Indexed: 04/19/2023]
Abstract
Focal epilepsy accounts for 60% of all forms of epilepsy, but the pathogenic mechanism is not well understood. In this study, three novel mutations in NPRL3 (nitrogen permease regulator-like 3), c.937_945del, c.1514dupC and 6,706-bp genomic DNA (gDNA) deletion, were identified in three families with focal epilepsy by linkage analysis, whole exome sequencing (WES) and Sanger sequencing. NPRL3 protein is a component of the GATOR1 complex, a major inhibitor of mTOR signaling. These mutations led to truncation of the NPRL3 protein and hampered the binding between NPRL3 and DEPDC5, which is another component of the GATOR1 complex. Consequently, the mutant proteins enhanced mTOR signaling in cultured cells, possibly due to impaired inhibition of mTORC1 by GATOR1. Knockdown of nprl3 in Drosophila resulted in epilepsy-like behavior and abnormal synaptic development. Taken together, these findings expand the genotypic spectrum of NPRL3-associated focal epilepsy and provide further insight into how NPRL3 mutations lead to epilepsy.
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Affiliation(s)
- Shiyue Du
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Sheng Zeng
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
- Department of Geriatrics, The Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Li Song
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Hongying Ma
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Rui Chen
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Junyu Luo
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Xu Wang
- National Reference Laboratory of Veterinary Drug Residues and MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan, 430070, China
| | - Tingbin Ma
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Xuan Xu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Hao Sun
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Ping Yi
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Jifeng Guo
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Yaling Huang
- Department of Neurology, Union Hospital of HUST, Wuhan, 430022, China
| | - Mugen Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Tao Wang
- Department of Neurology, Union Hospital of HUST, Wuhan, 430022, China
| | - Wei-Ping Liao
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University; Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou Medical University, Guangzhou, 510260, China
| | - Luoying Zhang
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China.
- Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan, 430022, China.
| | - Jing Yu Liu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China.
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China.
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, 410008, China.
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19
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Lee HM, Hong SJ, Gill R, Caldairou B, Wang I, Zhang JG, Deleo F, Schrader D, Bartolomei F, Guye M, Cho KH, Barba C, Sisodiya S, Jackson G, Hogan RE, Wong-Kisiel L, Cascino GD, Schulze-Bonhage A, Lopes-Cendes I, Cendes F, Guerrini R, Bernhardt B, Bernasconi N, Bernasconi A. Multimodal mapping of regional brain vulnerability to focal cortical dysplasia. Brain 2023; 146:3404-3415. [PMID: 36852571 PMCID: PMC10393418 DOI: 10.1093/brain/awad060] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 01/17/2023] [Accepted: 02/02/2023] [Indexed: 03/01/2023] Open
Abstract
Focal cortical dysplasia (FCD) type II is a highly epileptogenic developmental malformation and a common cause of surgically treated drug-resistant epilepsy. While clinical observations suggest frequent occurrence in the frontal lobe, mechanisms for such propensity remain unexplored. Here, we hypothesized that cortex-wide spatial associations of FCD distribution with cortical cytoarchitecture, gene expression and organizational axes may offer complementary insights into processes that predispose given cortical regions to harbour FCD. We mapped the cortex-wide MRI distribution of FCDs in 337 patients collected from 13 sites worldwide. We then determined its associations with (i) cytoarchitectural features using histological atlases by Von Economo and Koskinas and BigBrain; (ii) whole-brain gene expression and spatiotemporal dynamics from prenatal to adulthood stages using the Allen Human Brain Atlas and PsychENCODE BrainSpan; and (iii) macroscale developmental axes of cortical organization. FCD lesions were preferentially located in the prefrontal and fronto-limbic cortices typified by low neuron density, large soma and thick grey matter. Transcriptomic associations with FCD distribution uncovered a prenatal component related to neuroglial proliferation and differentiation, likely accounting for the dysplastic makeup, and a postnatal component related to synaptogenesis and circuit organization, possibly contributing to circuit-level hyperexcitability. FCD distribution showed a strong association with the anterior region of the antero-posterior axis derived from heritability analysis of interregional structural covariance of cortical thickness, but not with structural and functional hierarchical axes. Reliability of all results was confirmed through resampling techniques. Multimodal associations with cytoarchitecture, gene expression and axes of cortical organization indicate that prenatal neurogenesis and postnatal synaptogenesis may be key points of developmental vulnerability of the frontal lobe to FCD. Concordant with a causal role of atypical neuroglial proliferation and growth, our results indicate that FCD-vulnerable cortices display properties indicative of earlier termination of neurogenesis and initiation of cell growth. They also suggest a potential contribution of aberrant postnatal synaptogenesis and circuit development to FCD epileptogenicity.
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Affiliation(s)
- Hyo M Lee
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Seok-Jun Hong
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute, McGill University, Montreal, Canada
- Center for Neuroscience Imaging, Research Institute for Basic Science, Department of Global Biomedical Engineering, SungKyunKwan University, Suwon, KoreaSuwon, Korea
| | - Ravnoor Gill
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Benoit Caldairou
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Irene Wang
- Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Jian-guo Zhang
- Department of Functional Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Francesco Deleo
- Epilepsy Unit, Fondazione IRCCS Istituto Neurologico C. Besta, Milano, Italy
| | - Dewi Schrader
- Department of Pediatrics, British Columbia Children’s Hospital, Vancouver, Canada
| | - Fabrice Bartolomei
- Aix Marseille Univ, INSERM, INS, Institut de Neurosciences des Systèmes, Marseille, 13005, France
| | - Maxime Guye
- Aix Marseille University, CNRS, CRMBM UMR 7339, Marseille, France
| | - Kyoo Ho Cho
- Department of Neurology, Yonsei University College of Medicine, Seoul, Korea
| | - Carmen Barba
- Meyer Children's Hospital IRCCS, Florence, Italy
- University of Florence, 50121 Florence, Italy
| | - Sanjay Sisodiya
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, UK
| | - Graeme Jackson
- The Florey Institute of Neuroscience and Mental Health and The University of Melbourne, Victoria, Australia
| | - R Edward Hogan
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | | | | | | | - Iscia Lopes-Cendes
- Department of Translational Medicine, School of Medical Sciences, University of Campinas (UNICAMP) and the Brazilian Institute of Neuroscience and Neurotechnology (BRAINN), Campinas SP, Brazil
| | - Fernando Cendes
- Department of Neurology, School of Medical Sciences, University of Campinas (UNICAMP), and the Brazilian Institute of Neuroscience and Neurotechnology (BRAINN), Campinas SP, Brazil
| | - Renzo Guerrini
- Meyer Children's Hospital IRCCS, Florence, Italy
- University of Florence, 50121 Florence, Italy
| | - Boris Bernhardt
- Multimodal Imaging and Connectome Analysis Lab, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, QC, Canada
| | - Neda Bernasconi
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Andrea Bernasconi
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute, McGill University, Montreal, Canada
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20
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Wong W, Estep JA, Treptow AM, Rajabli N, Jahncke JN, Ubina T, Wright KM, Riccomagno MM. An adhesion signaling axis involving Dystroglycan, β1-Integrin, and Cas adaptor proteins regulates the establishment of the cortical glial scaffold. PLoS Biol 2023; 21:e3002212. [PMID: 37540708 PMCID: PMC10431685 DOI: 10.1371/journal.pbio.3002212] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 08/16/2023] [Accepted: 06/23/2023] [Indexed: 08/06/2023] Open
Abstract
The mature mammalian cortex is composed of 6 architecturally and functionally distinct layers. Two key steps in the assembly of this layered structure are the initial establishment of the glial scaffold and the subsequent migration of postmitotic neurons to their final position. These processes involve the precise and timely regulation of adhesion and detachment of neural cells from their substrates. Although much is known about the roles of adhesive substrates during neuronal migration and the formation of the glial scaffold, less is understood about how these signals are interpreted and integrated within these neural cells. Here, we provide in vivo evidence that Cas proteins, a family of cytoplasmic adaptors, serve a functional and redundant role during cortical lamination. Cas triple conditional knock-out (Cas TcKO) mice display severe cortical phenotypes that feature cobblestone malformations. Molecular epistasis and genetic experiments suggest that Cas proteins act downstream of transmembrane Dystroglycan and β1-Integrin in a radial glial cell-autonomous manner. Overall, these data establish a new and essential role for Cas adaptor proteins during the formation of cortical circuits and reveal a signaling axis controlling cortical scaffold formation.
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Affiliation(s)
- Wenny Wong
- Neuroscience Graduate Program, University of California, Riverside, California, United States of America
| | - Jason A. Estep
- Cell, Molecular and Developmental Biology Graduate Program, Department of Molecular, Cell & Systems Biology, University of California, Riverside, California, United States of America
| | - Alyssa M. Treptow
- Cell, Molecular and Developmental Biology Graduate Program, Department of Molecular, Cell & Systems Biology, University of California, Riverside, California, United States of America
| | - Niloofar Rajabli
- Cell, Molecular and Developmental Biology Graduate Program, Department of Molecular, Cell & Systems Biology, University of California, Riverside, California, United States of America
| | - Jennifer N. Jahncke
- Neuroscience Graduate Program, Vollum Institute, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Teresa Ubina
- Neuroscience Graduate Program, University of California, Riverside, California, United States of America
| | - Kevin M. Wright
- Neuroscience Graduate Program, Vollum Institute, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Martin M. Riccomagno
- Neuroscience Graduate Program, University of California, Riverside, California, United States of America
- Cell, Molecular and Developmental Biology Graduate Program, Department of Molecular, Cell & Systems Biology, University of California, Riverside, California, United States of America
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21
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Faraji J, Metz GAS. Toward reframing brain-social dynamics: current assumptions and future challenges. Front Psychiatry 2023; 14:1211442. [PMID: 37484686 PMCID: PMC10359502 DOI: 10.3389/fpsyt.2023.1211442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 06/19/2023] [Indexed: 07/25/2023] Open
Abstract
Evolutionary analyses suggest that the human social brain and sociality appeared together. The two fundamental tools that accelerated the concurrent emergence of the social brain and sociality include learning and plasticity. The prevailing core idea is that the primate brain and the cortex in particular became reorganised over the course of evolution to facilitate dynamic adaptation to ongoing changes in physical and social environments. Encouraged by computational or survival demands or even by instinctual drives for living in social groups, the brain eventually learned how to learn from social experience via its massive plastic capacity. A fundamental framework for modeling these orchestrated dynamic responses is that social plasticity relies upon neuroplasticity. In the present article, we first provide a glimpse into the concepts of plasticity, experience, with emphasis on social experience. We then acknowledge and integrate the current theoretical concepts to highlight five key intertwined assumptions within social neuroscience that underlie empirical approaches for explaining the brain-social dynamics. We suggest that this epistemological view provides key insights into the ontology of current conceptual frameworks driving future research to successfully deal with new challenges and possible caveats in favour of the formulation of novel assumptions. In the light of contemporary societal challenges, such as global pandemics, natural disasters, violent conflict, and other human tragedies, discovering the mechanisms of social brain plasticity will provide new approaches to support adaptive brain plasticity and social resilience.
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22
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Stoufflet J, Tielens S, Nguyen L. Shaping the cerebral cortex by cellular crosstalk. Cell 2023; 186:2733-2747. [PMID: 37352835 DOI: 10.1016/j.cell.2023.05.040] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 03/30/2023] [Accepted: 05/26/2023] [Indexed: 06/25/2023]
Abstract
The cerebral cortex is the brain's outermost layer. It is responsible for processing motor and sensory information that support high-level cognitive abilities and shape personality. Its development and functional organization strongly rely on cell communication that is established via an intricate system of diffusible signals and physical contacts during development. Interfering with this cellular crosstalk can cause neurodevelopmental disorders. Here, we review how crosstalk between migrating cells and their environment influences cerebral cortex development, ranging from neurogenesis to synaptogenesis and assembly of cortical circuits.
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Affiliation(s)
- Julie Stoufflet
- Laboratory of Molecular Regulation of Neurogenesis, GIGA-Stem Cells and GIGA-Neurosciences, Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of Liège, CHU Sart Tilman, Liège 4000, Belgium
| | - Sylvia Tielens
- Laboratory of Molecular Regulation of Neurogenesis, GIGA-Stem Cells and GIGA-Neurosciences, Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of Liège, CHU Sart Tilman, Liège 4000, Belgium
| | - Laurent Nguyen
- Laboratory of Molecular Regulation of Neurogenesis, GIGA-Stem Cells and GIGA-Neurosciences, Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of Liège, CHU Sart Tilman, Liège 4000, Belgium; Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Wavres, Belgium.
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23
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Boßelmann CM, Leu C, Lal D. Technological and computational approaches to detect somatic mosaicism in epilepsy. Neurobiol Dis 2023:106208. [PMID: 37343892 DOI: 10.1016/j.nbd.2023.106208] [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: 03/05/2023] [Revised: 06/03/2023] [Accepted: 06/16/2023] [Indexed: 06/23/2023] Open
Abstract
Lesional epilepsy is a common and severe disease commonly associated with malformations of cortical development, including focal cortical dysplasia and hemimegalencephaly. Recent advances in sequencing and variant calling technologies have identified several genetic causes, including both short/single nucleotide and structural somatic variation. In this review, we aim to provide a comprehensive overview of the methodological advancements in this field while highlighting the unresolved technological and computational challenges that persist, including ultra-low variant allele fractions in bulk tissue, low availability of paired control samples, spatial variability of mutational burden within the lesion, and the issue of false-positive calls and validation procedures. Information from genetic testing in focal epilepsy may be integrated into clinical care to inform histopathological diagnosis, postoperative prognosis, and candidate precision therapies.
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Affiliation(s)
- Christian M Boßelmann
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Costin Leu
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London, UK.
| | - Dennis Lal
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA; Stanley Center for Psychiatric Research, Broad Institute of Harvard and M.I.T., Cambridge, MA, USA; Cologne Center for Genomics (CCG), University of Cologne, Cologne, DE, USA
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24
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Faissner A. Low-density lipoprotein receptor-related protein-1 (LRP1) in the glial lineage modulates neuronal excitability. FRONTIERS IN NETWORK PHYSIOLOGY 2023; 3:1190240. [PMID: 37383546 PMCID: PMC10293750 DOI: 10.3389/fnetp.2023.1190240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 05/25/2023] [Indexed: 06/30/2023]
Abstract
The low-density lipoprotein related protein receptor 1 (LRP1), also known as CD91 or α-Macroglobulin-receptor, is a transmembrane receptor that interacts with more than 40 known ligands. It plays an important biological role as receptor of morphogens, extracellular matrix molecules, cytokines, proteases, protease inhibitors and pathogens. In the CNS, it has primarily been studied as a receptor and clearance agent of pathogenic factors such as Aβ-peptide and, lately, Tau protein that is relevant for tissue homeostasis and protection against neurodegenerative processes. Recently, it was found that LRP1 expresses the Lewis-X (Lex) carbohydrate motif and is expressed in the neural stem cell compartment. The removal of Lrp1 from the cortical radial glia compartment generates a strong phenotype with severe motor deficits, seizures and a reduced life span. The present review discusses approaches that have been taken to address the neurodevelopmental significance of LRP1 by creating novel, lineage-specific constitutive or conditional knockout mouse lines. Deficits in the stem cell compartment may be at the root of severe CNS pathologies.
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25
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Checri R, Chipaux M, Ferrand-Sorbets S, Raffo E, Bulteau C, Rosenberg SD, Doladilhe M, Dorfmüller G, Adle-Biassette H, Baldassari S, Baulac S. Detection of brain somatic mutations in focal cortical dysplasia during epilepsy presurgical workup. Brain Commun 2023; 5:fcad174. [PMID: 37324239 PMCID: PMC10261848 DOI: 10.1093/braincomms/fcad174] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 04/01/2023] [Accepted: 05/31/2023] [Indexed: 06/17/2023] Open
Abstract
Brain-restricted somatic variants in genes of the mechanistic target of rapamycin signalling pathway cause focal epilepsies associated with focal cortical dysplasia type II. We hypothesized that somatic variants could be identified from trace tissue adherent to explanted stereoelectroencephalography electrodes used in the presurgical epilepsy workup to localize the epileptogenic zone. We investigated three paediatric patients with drug-resistant focal epilepsy subjected to neurosurgery. In the resected brain tissue, we identified low-level mosaic somatic mutations in AKT3 and DEPDC5 genes. We collected stereoelectroencephalography depth electrodes in the context of a second presurgical evaluation and identified 4/33 mutation-positive electrodes that were either located in the epileptogenic zone or at the border of the dysplasia. We provide the proof-of-concept that somatic mutations with low levels of mosaicism can be detected from individual stereoelectroencephalography electrodes and support a link between the mutation load and the epileptic activity. Our findings emphasize future opportunities for integrating genetic testing from stereoelectroencephalography electrodes into the presurgical evaluation of refractory epilepsy patients with focal cortical dysplasia type II to improve the patients' diagnostic journey and guide towards precision medicine.
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Affiliation(s)
| | | | - Sarah Ferrand-Sorbets
- Department of Pediatric Neurosurgery, Rothschild Foundation Hospital EpiCARE, 75019, Paris, France
| | - Emmanuel Raffo
- Department of Pediatric Neurosurgery, Rothschild Foundation Hospital EpiCARE, 75019, Paris, France
- Unité de recherche 3450 DevAH, Développement, Adaptation et Handicap, Campus Brabois-Santé, Université de Lorraine, 54505, Vandoeuvre-lès-Nancy, France
| | - Christine Bulteau
- Department of Pediatric Neurosurgery, Rothschild Foundation Hospital EpiCARE, 75019, Paris, France
- Université de Paris Cité, MC2Lab, Institut de Psychologie, F-92100 Boulogne-Billancourt, France
| | | | - Marion Doladilhe
- Sorbonne Université, Institut du Cerveau—Paris Brain Institute—ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, 75013, Paris, France
| | - Georg Dorfmüller
- Department of Pediatric Neurosurgery, Rothschild Foundation Hospital EpiCARE, 75019, Paris, France
| | - Homa Adle-Biassette
- Université de Paris Cité, service d’Anatomie Pathologique, APHP, Hôpital Lariboisière, DMU DREAM, UMR 1141, INSERM, 75010, Paris, France
| | | | - Stéphanie Baulac
- Correspondence to: Stéphanie Baulac Institut du Cerveau, 47 bd de l’hôpital, 75013, Paris, France E-mail:
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26
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Bizzotto S. The human brain through the lens of somatic mosaicism. Front Neurosci 2023; 17:1172469. [PMID: 37250426 PMCID: PMC10213359 DOI: 10.3389/fnins.2023.1172469] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 04/25/2023] [Indexed: 05/31/2023] Open
Abstract
Every cell in the human brain possesses a unique genome that is the product of the accumulation of somatic mutations starting from the first postzygotic cell division and continuing throughout life. Somatic mosaicism in the human brain has been the focus of several recent efforts that took advantage of key technological innovations to start elucidating brain development, aging and disease directly in human tissue. On one side, somatic mutation occurring in progenitor cells has been used as a natural barcoding system to address cell phylogenies of clone formation and cell segregation in the brain lineage. On the other side, analyses of mutation rates and patterns in the genome of brain cells have revealed mechanisms of brain aging and disorder predisposition. In addition to the study of somatic mosaicism in the normal human brain, the contribution of somatic mutation has been investigated in both developmental neuropsychiatric and neurodegenerative disorders. This review starts with a methodological perspective on the study of somatic mosaicism to then cover the most recent findings in brain development and aging, and ends with the role of somatic mutations in brain disease. Thus, this review underlies what we have learned and what is still possible to discover by looking at somatic mosaicism in the brain genome.
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Gerasimenko A, Baldassari S, Baulac S. mTOR pathway: Insights into an established pathway for brain mosaicism in epilepsy. Neurobiol Dis 2023; 182:106144. [PMID: 37149062 DOI: 10.1016/j.nbd.2023.106144] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 05/02/2023] [Accepted: 05/03/2023] [Indexed: 05/08/2023] Open
Abstract
The mechanistic target of rapamycin (mTOR) signaling pathway is an essential regulator of numerous cellular activities such as metabolism, growth, proliferation, and survival. The mTOR cascade recently emerged as a critical player in the pathogenesis of focal epilepsies and cortical malformations. The 'mTORopathies' comprise a spectrum of cortical malformations that range from whole brain (megalencephaly) and hemispheric (hemimegalencephaly) abnormalities to focal abnormalities, such as focal cortical dysplasia type II (FCDII), which manifest with drug-resistant epilepsies. The spectrum of cortical dysplasia results from somatic brain mutations in the mTOR pathway activators AKT3, MTOR, PIK3CA, and RHEB and from germline and somatic mutations in mTOR pathway repressors, DEPDC5, NPRL2, NPRL3, TSC1 and TSC2. The mTORopathies are characterized by excessive mTOR pathway activation, leading to a broad range of structural and functional impairments. Here, we provide a comprehensive literature review of somatic mTOR-activating mutations linked to epilepsy and cortical malformations in 292 patients and discuss the perspectives of targeted therapeutics for personalized medicine.
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Affiliation(s)
- Anna Gerasimenko
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, 75013 Paris, France; APHP Sorbonne Université, GH Pitié Salpêtrière et Trousseau, Département de Génétique, Centre de référence "déficiences intellectuelles de causes rares", Paris, France
| | - Sara Baldassari
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, 75013 Paris, France
| | - Stéphanie Baulac
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, 75013 Paris, France.
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Garavatti E, Yamamoto E, Collins K, Selden N, Bushlin I. Surgical Resection of Focal Cortical Dysplasia in a Neonate with Novel TSC1 Mutation Leading to Resolution of Refractory Seizures: Case Report. Child Neurol Open 2023; 10:2329048X231219223. [PMID: 38107744 PMCID: PMC10722926 DOI: 10.1177/2329048x231219223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/20/2023] [Accepted: 11/17/2023] [Indexed: 12/19/2023] Open
Abstract
We describe a neonate presenting on first day of life with refractory seizures secondary to a single, large area of focal cortical dysplasia (FCD) who underwent surgical resection at age 3 weeks leading to resolution of seizure activity and dramatic improvement in developmental trajectory. Surgical intervention for epilepsy is infrequently offered for neonates, often reserved only for those with catastrophic presentations. This case demonstrates that surgical intervention can be safe and efficacious in neonates for pharmaco-resistant seizures associated with a focal lesion. Rapid whole exome sequencing in this case yielded a germline novel de novo TSC1 mutation, leading to a genetic diagnosis of tuberous sclerosis complex (TSC). Our patient demonstrates an atypical neonatal presentation of TSC. Limited data is available for those with isolated FCD in TSC; this is the first reported case in a neonate.
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Affiliation(s)
- Emily Garavatti
- Neurodevelopmental Disabilities, Oregon Health & Science University School of Medicine, Portland, OR, USA
| | - Erin Yamamoto
- Neurosurgery, Oregon Health & Science University School of Medicine, Portland, OR, USA
| | - Kelly Collins
- Department of Neurosurgery, Oregon Health & Science University, Portland, OR, USA
| | - Nathan Selden
- Department of Neurosurgery, Oregon Health & Science University, Portland, OR, USA
| | - Ittai Bushlin
- Department of Pediatric Neurology, Oregon Health & Science University, Portland, OR, USA
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