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Man A, Di Scipio M, Grewal S, Suk Y, Trinari E, Ejaz R, Whitney R. The Genetics of Tuberous Sclerosis Complex and Related mTORopathies: Current Understanding and Future Directions. Genes (Basel) 2024; 15:332. [PMID: 38540392 PMCID: PMC10970281 DOI: 10.3390/genes15030332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 03/02/2024] [Accepted: 03/02/2024] [Indexed: 06/14/2024] Open
Abstract
The mechanistic target of rapamycin (mTOR) pathway serves as a master regulator of cell growth, proliferation, and survival. Upregulation of the mTOR pathway has been shown to cause malformations of cortical development, medically refractory epilepsies, and neurodevelopmental disorders, collectively described as mTORopathies. Tuberous sclerosis complex (TSC) serves as the prototypical mTORopathy. Characterized by the development of benign tumors in multiple organs, pathogenic variants in TSC1 or TSC2 disrupt the TSC protein complex, a negative regulator of the mTOR pathway. Variants in critical domains of the TSC complex, especially in the catalytic TSC2 subunit, correlate with increased disease severity. Variants in less crucial exons and non-coding regions, as well as those undetectable with conventional testing, may lead to milder phenotypes. Despite the assumption of complete penetrance, expressivity varies within families, and certain variants delay disease onset with milder neurological effects. Understanding these genotype-phenotype correlations is crucial for effective clinical management. Notably, 15% of patients have no mutation identified by conventional genetic testing, with the majority of cases postulated to be caused by somatic TSC1/TSC2 variants which present complex diagnostic challenges. Advancements in genetic testing, prenatal screening, and precision medicine hold promise for changing the diagnostic and treatment paradigm for TSC and related mTORopathies. Herein, we explore the genetic and molecular mechanisms of TSC and other mTORopathies, emphasizing contemporary genetic methods in understanding and diagnosing the condition.
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Affiliation(s)
- Alice Man
- Michael G. DeGroote School of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Matteo Di Scipio
- Michael G. DeGroote School of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Shan Grewal
- Michael G. DeGroote School of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Yujin Suk
- Michael G. DeGroote School of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Elisabetta Trinari
- Division of Developmental Pediatrics, Department of Pediatrics, McMaster Children’s Hospital, Hamilton, ON L8N 3Z5, Canada
| | - Resham Ejaz
- Division of Genetics, Department of Pediatrics, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Robyn Whitney
- Division of Neurology, Department of Pediatrics, McMaster University, Hamilton, ON L8S 4L8, Canada
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Liu L, Wang Y, Zhang Z, Yu C, Chen J. Identification of a novel TSC1 gene variant in a patient with atypical vitiligo-like skin lesions: Unveiling the hidden tuberous sclerosis complex. Mol Genet Genomic Med 2024; 12:e2403. [PMID: 38439608 PMCID: PMC10912791 DOI: 10.1002/mgg3.2403] [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: 10/31/2023] [Revised: 01/04/2024] [Accepted: 02/05/2024] [Indexed: 03/06/2024] Open
Abstract
BACKGROUND Tuberous sclerosis complex (TSC), an autosomal-dominant disorder, is characterized by hamartomas affecting multiple organ systems. The underlying etiology of TSC is the pathogenic variations of the TSC1 or TSC2 genes. The phenotype variability of TSC could lead to missed diagnosis; therefore, the latest molecular diagnostic criteria for identifying a heterozygous pathogenic variant in either the TSC1 or TSC2 gene filled this gap. Furthermore, the pathogenicity of numerous variants remains unverified, potentially leading to misinterpretations of their functional consequences. METHODS In this study, a single patient presenting with atypical vitiligo-like skin lesions suspected to have TSC was enrolled. Targeted next-generation sequencing and Sanger sequencing were employed to identify a pathogenic variant. Additionally, a minigene splicing assay was conducted to assess the impact of TSC1 c.1030-2A>T, located in intron 10, on RNA splicing. RESULTS A novel TSC1: c.1030-2A>T heterozygosis variant was identified in intron 10. In vitro minigene assay revealed that the c.1030-2A>T variant caused exon 11 skipping, resulting in a frameshift in the absence of 112 base pairs of mature messenger RNA and premature termination after 174 base pairs (p.Ala344Glnfs*59). CONCLUSION The detection of this novel pathogenic TSC1 variant in the patient with atypical vitiligo-like skin lesions enrolled in our study ultimately resulted in the diagnosis of TSC. As a result, our study contributes to expanding the mutational spectrum of the TSC1 gene and refining the genotype-phenotype map of TSC.
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Affiliation(s)
- Linli Liu
- Department of DermatologyThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina
- Department of DermatologySuining Central HospitalSuiningSichuanChina
| | - Yanbo Wang
- Department of DermatologyLangzhong People's HospitalNanchongSichuanChina
| | - Zhengzhong Zhang
- Department of DermatologyAffiliated Hospital of North Sichuan Medical CollegeNanchongSichuanChina
| | - Chunshui Yu
- Department of DermatologySuining Central HospitalSuiningSichuanChina
| | - Jin Chen
- Department of DermatologyThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina
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Mammadova D, Vecko J, Hofmann M, Schüssler SC, Deiters L, Canda A, Wieland AK, Gollwitzer S, Hamer H, Trollmann R. A single-center observational study on long-term neurodevelopmental outcomes in children with tuberous sclerosis complex. Orphanet J Rare Dis 2023; 18:349. [PMID: 37946245 PMCID: PMC10637019 DOI: 10.1186/s13023-023-02959-0] [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: 11/14/2022] [Accepted: 10/25/2023] [Indexed: 11/12/2023] Open
Abstract
BACKGROUND Tuberous sclerosis complex (TSC) is a rare multisystem disorder caused by mutations in the TSC1 or TSC2 gene. More than 90% of patients with TSC develop neurological and/or neuropsychiatric manifestations. The aim of the present study was to determine the developmental and cognitive long-term outcomes of pediatric TSC patients. METHODS This cross-sectional, monocenter study included pediatric TSC patients who received multidisciplinary long-term care with a last visit between 2005 and 2019. Neurological manifestations and cognitive development (BSID, K-ABC) were analyzed in relation to age and type of mutation. RESULTS Thirty-five patients aged 13.5 ± 7.8 years were included in the study. Diagnosis was confirmed genetically in 65.7% of patients (TSC1, 26.1%; TSC2, 65.2%; NMI, 8.7%). Mean age at diagnosis was 1.3 ± 3.5 years; 74.3% of the patients had been diagnosed within the first year of life due to seizures (62.9%) or/and cardiac rhabdomyomas (28.6%). The most common TSC manifestations included structural brain lesions (cortical tubers, 91.4%; subependymal nodules, 82.9%), epilepsy (85.7%), and cardiac rhabdomyomas (62.9%). Mean age at seizure onset was 1.5 ± 2.3 years, with onset in 80.0% of patients within the first two years of life. Infantile spasms, which were the first seizure type in 23.3% of the patients, developed earlier (0.6 ± 0.4 years) than focal seizures (1.8 ± 2.5 years). Refractory epilepsy was present in 21 (70.0%) patients, mild or severe intellectual impairment in 66.6%, and autism spectrum disorders in 11.4%. Severe cognitive impairment (33.3%) was significantly associated with epilepsy type and age at seizure onset (p < 0.05). CONCLUSIONS The results emphasized the phenotypic variability of pediatric-onset TSC and the high rate of neurological and neuropsychiatric morbidity. Early-onset refractory epilepsy was associated with impaired cognitive development. Children of all ages with TSC require multidisciplinary long-term care and individual early-intervention programs.
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Affiliation(s)
- D Mammadova
- Department of Pediatric and Adolescent Medicine, Pediatric Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestr. 15, 91054, Erlangen, Germany
| | - J Vecko
- Department of Pediatric and Adolescent Medicine, Pediatric Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestr. 15, 91054, Erlangen, Germany
| | - M Hofmann
- Department of Pediatric and Adolescent Medicine, Pediatric Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestr. 15, 91054, Erlangen, Germany
| | - S C Schüssler
- Department of Pediatric and Adolescent Medicine, Pediatric Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestr. 15, 91054, Erlangen, Germany
| | - L Deiters
- Department of Pediatric and Adolescent Medicine, Pediatric Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestr. 15, 91054, Erlangen, Germany
| | - A Canda
- Department of Pediatric and Adolescent Medicine, Pediatric Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestr. 15, 91054, Erlangen, Germany
| | - A K Wieland
- Department of Pediatric and Adolescent Medicine, Pediatric Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestr. 15, 91054, Erlangen, Germany
- Center of Rare Diseases Erlangen (ZSEER), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - S Gollwitzer
- Department of Neurology, Epilepsy Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
- Center of Rare Diseases Erlangen (ZSEER), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - H Hamer
- Department of Neurology, Epilepsy Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
- Center of Rare Diseases Erlangen (ZSEER), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Regina Trollmann
- Department of Pediatric and Adolescent Medicine, Pediatric Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestr. 15, 91054, Erlangen, Germany.
- Center of Rare Diseases Erlangen (ZSEER), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
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Zhou H, Zheng Z, Tu Z, Li Y, Yang J, Fan C. Cardiac self-limiting rhabdomyomas in a neonatal patient with tuberous sclerosis complex: a case report with negative genetic testing. Front Pediatr 2023; 11:1263631. [PMID: 37881637 PMCID: PMC10597626 DOI: 10.3389/fped.2023.1263631] [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: 07/20/2023] [Accepted: 09/27/2023] [Indexed: 10/27/2023] Open
Abstract
Background Tuberous Sclerosis Complex (TSC) is a hereditary condition that leads to the development of non-malignant neoplasms in various organs, including cardiac rhabdomyomas, which can cause significant complications. Case presentation This report describes the case of a 15-day-old male neonate who was hospitalized due to intracardiac masses and brain lesions, despite the absence of TSC gene mutations. The patient's mother exhibited facial angiofibromas, a common feature of TSC. Over a 2-year follow-up period, spontaneous regression of the cardiac tumor was observed. Conclusions This case illustrates that not all TSC cases exhibit detectable TSC gene mutations. Current treatment strategies, such as mTOR inhibitors, offer potential effectiveness in managing associated cardiac rhabdomyomas. Further research should focus on evaluating the therapeutic potential of these inhibitors.
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Affiliation(s)
| | | | | | | | | | - Chengming Fan
- Department of the Cardiovascular Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
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Curatolo P, Trivisano M, Specchio N. Updated Genotype-Phenotype Correlations in TSC. Semin Pediatr Neurol 2023; 47:101086. [PMID: 37919037 DOI: 10.1016/j.spen.2023.101086] [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: 11/04/2023]
Abstract
GENOTYPE/PHENOTYPE CORRELATIONS IN TUBEROUS SCLEROSIS COMPLEX Paolo Curatolo MD, Romina Moavero MD, Denis Roberto, Federica Graziola Seminars in Pediatric Neurology Volume 22, Issue 4, December 2015, Pages 259-273 Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by the development of widespread hamartomatous lesions in various organs, including brain, skin, kidneys, heart, and eyes. Central nervous system is almost invariably involved, with up to 85% of patients presenting with epilepsy, and at least half of patients having intellectual disability or other neuropsychiatric disorders including autism spectrum disorder. TSC is caused by the mutation in one of the 2 genes TSC1, at 9q34, and TSC2, at 16p13.3. They respectively encode for hamartin and tuberin, which form an intracellular complex inhibiting the mammalian target of rapamycin. Mammalian target of rapamycin overactivation following the genetic defect determines the cell growth and proliferation responsible for TSC-related lesions, as well as the alterations in neuronal excitability and synaptogenesis leading to epilepsy and neuropsychiatric disorders. A causative mutation for the disorder is identified in about 85% of patients with a clinical diagnosis of TSC. Mosaicism and technology limits likely explain most of the no mutation identified cases. This review confirms that patients with TSC2 mutations considered as a group usually present a more severe phenotype, characterized by higher number of tubers, earlier age at seizure onset and higher prevalence of intellectual disability. However, the clinical phenotype of the disease presents a high variability, thus making the prediction of the phenotype on an individual basis still challenging. The increasing application of new molecular techniques to subjects with TSC has the potential to significantly reduce the rate of patients with no mutation demonstrated and to identify an increasing higher number of mutations. This would hopefully allow a better characterization of higher risk mutations, which might help clinicians to plan individualized surveillance plans. Furthermore, the increasing availability of disease registries to collect clinical and genetics data of patients help to define more valid and clinically oriented genotype or phenotype correlations.
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Affiliation(s)
- Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University, Rome, Italy
| | - Marina Trivisano
- Child Neurology, Epilepsy and Movement Disorders, Bambino Gesù, IRCCS Children's Hospital, Full Member of European Reference Network EpiCARE, Rome, Italy
| | - Nicola Specchio
- Child Neurology, Epilepsy and Movement Disorders, Bambino Gesù, IRCCS Children's Hospital, Full Member of European Reference Network EpiCARE, Rome, Italy.
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Orosz P, Kollák Z, Pethő Á, Fogarasi A, Reusz G, Hadzsiev K, Szabó T. The Importance of Genetic Testing in the Differential Diagnosis of Atypical TSC2-PKD1 Contiguous Gene Syndrome—Case Series. CHILDREN 2023; 10:children10030420. [PMID: 36979978 PMCID: PMC10047143 DOI: 10.3390/children10030420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 02/18/2023] [Accepted: 02/21/2023] [Indexed: 02/24/2023]
Abstract
Background: In clinical practice, the possible diagnosis of tuberous sclerosis or polycystic kidney disease is primarily based on clinical criteria, which can later be verified by genetic testing. But in the case of TSC2/PKD1 contiguous gene syndrome (TSC2/PKD1-CGS), the renal appearance of the disease is more serious. Therefore, early genetic analysis is recommended. Methods: Herein we present the report of four children with TSC2/PKD1-CGS, one involving the NTHL1 gene. We aim to emphasize the importance of genetic testing in this rare syndrome. Results: During the follow-up of tuberous sclerosis and polycystic kidney disease patients, it is essential to reappraise the diagnosis if the clinical symptoms’ appearance or onset time is unusual. Targeted genetic testing is recommended. However, early tumor formation necessitates the extension of genetic analysis. Conclusions: An appropriate evaluation of the phenotype is the cornerstone of diagnosing the rare TSC2/PKD1-CGS with the help of genetic results. In addition, malignant tumors could draw attention to an infrequent large deletion.
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Affiliation(s)
- Petronella Orosz
- Bethesda Children’s Hospital, 1146 Budapest, Hungary
- Department of Pediatrics, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Zita Kollák
- Bethesda Children’s Hospital, 1146 Budapest, Hungary
| | - Ákos Pethő
- Department of Internal Medicine and Oncology Clinic, Faculty of Medicine, Semmelweis University, 1083 Budapest, Hungary
- Correspondence: (Á.P.); (T.S.)
| | | | - György Reusz
- 1st Department of Pediatrics, Faculty of Medicine, Semmelweis University, 1083 Budapest, Hungary
| | - Kinga Hadzsiev
- Department of Medical Genetics, Medical School, Clinical Centre, University of Pécs, 7624 Pécs, Hungary
| | - Tamás Szabó
- Department of Pediatrics, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Correspondence: (Á.P.); (T.S.)
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Giannikou K, Martin KR, Abdel-Azim AG, Pamir KJ, Hougard TR, Bagwe S, Tang Y, MacKeigan JP, Kwiatkowski DJ, Henske EP, Lam HC. Spectrum of germline and somatic mitochondrial DNA variants in Tuberous Sclerosis Complex. Front Genet 2023; 13:917993. [PMID: 36793390 PMCID: PMC9923026 DOI: 10.3389/fgene.2022.917993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 11/23/2022] [Indexed: 02/03/2023] Open
Abstract
Tuberous Sclerosis Complex (TSC) is caused by loss of function variants in either TSC1 or TSC2 and is characterized by broad phenotypic heterogeneity. Currently, there is limited knowledge regarding the role of the mitochondrial genome (mtDNA) in TSC pathogenesis. In this study, we aimed to determine the prevalence and spectrum of germline and somatic mtDNA variants in TSC and identify potential disease modifiers. Analysis of mtDNA amplicon massively parallel sequencing (aMPS) data, off-target mtDNA from whole-exome sequencing (WES), and/or qPCR, revealed mtDNA alterations in 270 diverse tissues (139 TSC-associated tumors and 131 normal tissue samples) from 199 patients and six healthy individuals. Correlation of clinical features to mtDNA variants and haplogroup analysis was done in 102 buccal swabs (age: 20-71 years). No correlation was found between clinical features and either mtDNA variants or haplogroups. No pathogenic variants were identified in the buccal swab samples. Using in silico analysis, we identified three predicted pathogenic variants in tumor samples: MT-ND4 (m.11742G>A, p. Cys328Tyr, VAF: 43%, kidney angiomyolipoma), MT-CYB (m.14775T>C, p. Leu10Pro, VAF: 43%, LAM abdominal tumor) and MT-CYB (m.15555C>T, p. Pro270Leu, VAF: 7%, renal cell carcinoma). Large deletions of the mitochondrial genome were not detected. Analysis of tumors from 23 patients with corresponding normal tissue did not reveal any recurrent tumor-associated somatic variants. The mtDNA/gDNA ratio between tumors and corresponding normal tissue was also unchanged. Overall, our findings demonstrate that the mitochondrial genome is highly stable across tissues and within TSC-associated tumors.
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Affiliation(s)
- Krinio Giannikou
- Cancer Genetics Laboratory, Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
- Division of Hematology/Oncology, Cancer and Blood Disease Institute, Children’s Hospital Los Angeles, Los Angeles, CA, United States
| | - Katie R. Martin
- Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Ahmad G. Abdel-Azim
- Cancer Genetics Laboratory, Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Kaila J. Pamir
- Center for LAM Research and Clinical Care, Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Thomas R. Hougard
- Center for LAM Research and Clinical Care, Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Shefali Bagwe
- Center for LAM Research and Clinical Care, Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Yan Tang
- Center for LAM Research and Clinical Care, Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Jeffrey P. MacKeigan
- Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - David J. Kwiatkowski
- Cancer Genetics Laboratory, Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Elizabeth P. Henske
- Center for LAM Research and Clinical Care, Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Hilaire C. Lam
- Center for LAM Research and Clinical Care, Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
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Shimada T, Yamagata K. Spine morphogenesis and synapse formation in tubular sclerosis complex models. Front Mol Neurosci 2022; 15:1019343. [PMID: 36606143 PMCID: PMC9807618 DOI: 10.3389/fnmol.2022.1019343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 12/05/2022] [Indexed: 12/24/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is caused by mutations in the Tsc1 or Tsc2 genes, whose products form a complex and inactivate the small G-protein Rheb1. The activation of Rheb1 may cause refractory epilepsy, intellectual disability, and autism, which are the major neuropsychiatric manifestations of TSC. Abnormalities in dendritic spines and altered synaptic structure are hallmarks of epilepsy, intellectual disability, and autism. In addition, spine dysmorphology and aberrant synapse formation are observed in TSC animal models. Therefore, it is important to investigate the molecular mechanism underlying the regulation of spine morphology and synapse formation in neurons to identify therapeutic targets for TSC. In this review, we focus on the representative proteins regulated by Rheb1 activity, mTORC1 and syntenin, which are pivotal downstream factors of Rheb1 in the alteration of spine formation and synapse function in TSC neurons.
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Affiliation(s)
- Tadayuki Shimada
- Child Brain Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan,*Correspondence: Tadayuki Shimada,
| | - Kanato Yamagata
- Child Brain Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan,Department of Psychiatry, Takada Nishishiro Hospital, Niigata, Japan,Kanato Yamagata,
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Luo C, Zhang Y, Zhang YS, Zhang MX, Ning J, Chen MF, Li Y, Qi L, Zu XB, Li YL, Cai Y. Renal phenotypes correlate with genotypes in unrelated individuals with tuberous sclerosis complex in China. Orphanet J Rare Dis 2022; 17:288. [PMID: 35870981 PMCID: PMC9308181 DOI: 10.1186/s13023-022-02443-1] [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: 12/13/2021] [Accepted: 07/14/2022] [Indexed: 11/22/2022] Open
Abstract
Purpose To explore the relationship between the genotype and renal phenotype in a Chinese cohort and guide clinical decision-making for treating tuberous sclerosis complex (TSC). Materials and methods We reviewed 173 patients with definite TSC at three centers in China from September 2014 to September 2020. All the patients underwent TSC1 and TSC2 genetic testing as well as renal phenotypic evaluation. All analyses were performed using the SPSS software, version 19.0, with a cut-off P value of 0.05 considered statistically significant. Results We identified variants in 93% (161/173) cases, including 16% TSC1 and 77% TSC2 variants. Analysis of the relationship between the genotype and renal phenotype, revealed that those with TSC2 variants were more likely to develop severe renal AML (> 4) (P = 0.044). In terms of treatment, TSC2 variants were more likely to undergo nephrectomy/partial nephrectomy (P = 0.036) and receive mTOR medication such as everolimus (P < 0.001). However, there was no significant difference between the two groups in terms of their response to the everolimus treatment. Conclusion Patients with TSC2 variants exhibit more severe renal phenotypes, especially those associated with renal angiomyolipomas (AML), and they often require nephrectomy/partial nephrectomy or mTOR medication. Detection of the genotype is helpful in TSC management. Supplementary Information The online version contains supplementary material available at 10.1186/s13023-022-02443-1.
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Xu H, Zhao Y, Zhao Q, Shi M, Zhang Z, Ding W, Zhao Y. Tuberous Sclerosis Complex 1 Deficiency in Macrophages Promotes Unclassical Inflammatory Response to Lipopolysaccharide In Vitro and Dextran Sodium Sulfate-Induced Colitis in Mice. Aging Dis 2022; 13:1875-1890. [PMID: 36465179 PMCID: PMC9662278 DOI: 10.14336/ad.2022.0408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Accepted: 04/08/2022] [Indexed: 09/01/2023] Open
Abstract
Human tuberous sclerosis (TSC) is mainly caused by genetic mutations of tuberous TSC1or TSC2. Recent studies found that TSC1 deficiency promoted classical M1 macrophage polarization. However, whether TSC1 regulates other inflammatory cytokine expression in lipopolysaccharidem (LPS)-stimulated macrophages is unknown. Herein, we studied the cytokine expression profile of wild-type (WT) and TSC1-deleted macrophages after LPS stimulation in vitro and the pathogenesis of dextran sodium sulfate (DSS)-induced colitis in mice with myeloid-specific TSC1 deletion (TSC1cKO mice). We found that TSC1-deficient macrophages exhibited the enhanced secretion of interleukin-17A (IL-17A), IL-17F, and interferon-gamma (IFN-γ) in response to LPS stimulation in vitro. This is in contrast to LPS-stimulated WT macrophages, which usually do not. Importantly, TSC1cKO mice exhibited exacerbated DSS-induced acute colitis with severer symptoms. MTOR deletion or rapamycin treatment significantly reversed the enhanced expressions of IL-17A, IL-17F, and IFN-γ in LPS-stimulated TSC1-deficient macrophages in vitro and rescued the enhanced DSS-induced colitis in TSC1cKO mice, indicating that TSC1 deficiency increased these cytokine productions in an mTOR-dependent manner. RNA-sequencing and molecular studies indicated that TSC1 deficiency enhanced the aerobic glycolysis process and the activities of mTOR-STAT3-RORγT pathway in LPS-stimulated macrophages. Inhibition of aerobic glycolysis, STAT3, or RORγT reversed IL-17 and IFN-γ expression in LPS-treated TSC1-deficient macrophages. Thus, TSC1 is essential for macrophages to shut down IL-17A, IL-17F, and IFN-γ expression during LPS stimulation by suppressing the aerobic glycolysis process and mTOR-STAT3, RORγT, and T-bet pathways. The present study uncovered the key role of TSC1 in shutting down IL-17A, IL-17F, and IFN-γ expressions in LPS-treated macrophages.
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Affiliation(s)
- Huawen Xu
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- Cunji Medical College, University of Chinese Academy of Sciences, Beijing, China.
| | - Yang Zhao
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- Cunji Medical College, University of Chinese Academy of Sciences, Beijing, China.
| | - Qingjie Zhao
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- Laboratory of Environment and Health, College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.
| | - Mingpu Shi
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- Cunji Medical College, University of Chinese Academy of Sciences, Beijing, China.
| | - Zhaoqi Zhang
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- Cunji Medical College, University of Chinese Academy of Sciences, Beijing, China.
| | - Wenjun Ding
- Laboratory of Environment and Health, College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.
| | - Yong Zhao
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- Cunji Medical College, University of Chinese Academy of Sciences, Beijing, China.
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China.
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Advances in the genetics and neuropathology of tuberous sclerosis complex: edging closer to targeted therapy. Lancet Neurol 2022; 21:843-856. [DOI: 10.1016/s1474-4422(22)00213-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 03/09/2022] [Accepted: 05/11/2022] [Indexed: 12/23/2022]
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12
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Yang XY, Meng Y, Wang YY, Lu YP, Wang QH, You YQ, Xie XX, Bai L, Fang N, Zou LP. Noninvasive prenatal diagnosis based on cell-free DNA for tuberous sclerosis: A pilot study. Mol Genet Genomic Med 2022; 10:e1952. [PMID: 35429229 PMCID: PMC9266619 DOI: 10.1002/mgg3.1952] [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: 12/23/2021] [Revised: 02/11/2022] [Accepted: 04/01/2022] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Noninvasive prenatal diagnosis (NIPD) based on cell-free DNA (cfDNA) has been introduced into the clinical application for some monogenic disorders but not for tuberous sclerosis (TSC) yet, which is an autosomal dominant disease caused by various variations in TSC1 or TSC2 gene. We aimed to explore the feasibility of NIPD on TSC. METHODS We recruited singleton pregnancies at risk of TSC from 14 families with a proband child. Definitive NIPD for TSC was performed using targeted next-generation sequencing of cfDNA in parallel with maternal white blood cell DNA (wbcDNA). The NIPD results were validated by amniocentesis or postnatal gene testing and follow-up of the born children. RESULTS Missense mutations, nonsense mutations, frameshift mutations, and splice-site variants which were obtained through de-novo, maternal, or paternal inheritance were included. The mean and minimum gestational weeks of NIPD were 17.18 ± 5.83 and 8 weeks, respectively. The NIPD results were 100% consistent with the amniocentesis or postnatal gene testing and follow-up of the born children. CONCLUSION This study demonstrates that NIPD based on cfDNA is feasible for TSC, but required to be confirmed with more samples. Studies on TSC can contribute to the application and promotion of NIPD for monogenic disorders.
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Affiliation(s)
- Xiao-Yan Yang
- Medical School of Chinese PLA General Hospital, Beijing, China.,Department of Pediatrics, The First Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Yan Meng
- Department of Pediatrics, The First Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Yang-Yang Wang
- Department of Pediatrics, The First Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Yan-Ping Lu
- Department of Obstetrics and Gynecology, The First Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Qiu-Hong Wang
- Medical School of Chinese PLA General Hospital, Beijing, China.,Department of Pediatrics, The First Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Yan-Qin You
- Department of Obstetrics and Gynecology, The First Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Xiao-Xiao Xie
- Department of Obstetrics and Gynecology, The First Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Ling Bai
- Beijing Scisoon Biotechnology Co., Ltd, Beijing, China
| | - Nan Fang
- Beijing Scisoon Biotechnology Co., Ltd, Beijing, China
| | - Li-Ping Zou
- Medical School of Chinese PLA General Hospital, Beijing, China.,Department of Pediatrics, The First Medical Center of Chinese PLA General Hospital, Beijing, China.,Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University, Beijing, China
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13
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De Ridder J, Kotulska K, Curatolo P, Jansen AC, Aronica E, Kwiatkowski DJ, Jansen FE, Jóźwiak S, Lagae L. Evolution of electroencephalogram in infants with tuberous sclerosis complex and neurodevelopmental outcome: a prospective cohort study. Dev Med Child Neurol 2022; 64:495-501. [PMID: 34601720 DOI: 10.1111/dmcn.15073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 09/06/2021] [Accepted: 09/07/2021] [Indexed: 01/20/2023]
Abstract
AIM To describe the evolution of electroencephalogram (EEG) characteristics in infants with tuberous sclerosis complex (TSC) and the relationship with neurodevelopmental outcome at 24 months. METHOD Eighty-three infants were enrolled in the EPISTOP trial and underwent serial EEG follow-up until the age of 24 months (males n=45, females n=37, median age at enrolment 28d, interquartile range 14-54d). Maturation of the EEG background and epileptiform discharges were compared between the TSC1 and TSC2 variants and between preventive and conventional groups respectively. RESULTS Children with TSC2 more frequently had a slower posterior dominant rhythm (PDR) at 24 months (51% vs 11%, p=0.002), a higher number of epileptiform foci (median=8 vs 4, p=0.003), and a lower fraction of EEGs without epileptiform discharges (18% vs 61%, p=0.001) at follow-up. A slower PDR at 24 months was significantly associated with lower cognitive (median=70 vs 80, p=0.028) and motor developmental quotients (median=70 vs 79, p=0.008). A higher fraction of EEGs without epileptiform discharges was associated with a lower probability of autism spectrum disorder symptoms (odds ratio=0.092, 95% confidence interval=0.009-0.912, p=0.042) and higher cognitive (p=0.004), language (p=0.002), and motor (p=0.001) developmental quotients at 24 months. INTERPRETATION TSC2 is associated with more abnormal EEG characteristics compared to TSC1, which are predictive for neurodevelopmental outcome.
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Affiliation(s)
- Jessie De Ridder
- Department of Development and Regeneration, Section Pediatric Neurology, Catholic University of Leuven (KU Leuven), Leuven, Belgium
| | - Katarzyna Kotulska
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warsaw, Poland
| | - Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University, Rome, Italy
| | - Anna C Jansen
- Pediatric Neurology Unit, University Hospital Brussel, Brussels, Belgium
| | - Eleonora Aronica
- Department of (Neuro) Pathology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands.,Stichting Epilepsie Instellingen Nederland, Heemstede, the Netherlands
| | | | - Floor E Jansen
- Department of Child Neurology, Brain Centre, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Sergiusz Jóźwiak
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warsaw, Poland.,Department of Child Neurology, Medical University of Warsaw, Warsaw, Poland
| | - Lieven Lagae
- Department of Development and Regeneration, Section Pediatric Neurology, Catholic University of Leuven (KU Leuven), Leuven, Belgium
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14
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Duan J, Ye Y, Hu Z, Zhao X, Liao J, Chen L. Identification of a Novel Canonical Splice Site Variant TSC2 c.2967-1G>T That is Not Associated With Tuberous Sclerosis Pathogenesis. Front Genet 2022; 13:904224. [PMID: 35692821 PMCID: PMC9184681 DOI: 10.3389/fgene.2022.904224] [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: 03/25/2022] [Accepted: 05/16/2022] [Indexed: 11/27/2022] Open
Abstract
Tuberous sclerosis, also known as tuberous sclerosis complex (TSC), is an autosomal dominant defect characterized by hamartomas in multiple organ systems. Inactivating variants cause this defect in either the TSC1 gene or the TSC2 gene, leading to hamartin or tuberin protein dysfunction, thus resulting in TSC. The diagnostic criteria for TSC suggest that it can be diagnosed by identifying a heterozygous pathogenic variant of TSC1 or TSC2, even in the absence of clinical signs. In a 4-year-old girl, we identified a splicing variant (NM_000548.4: c.2967-1G>T) that she inherited from her father. Neither the girl (patient) nor her father showed typical features of TSC. This variant is located in a NAGNAG acceptor, which can produce mRNA isoforms that differ by a three-nucleotide indel. Reverse transcription polymerase chain reaction analysis of the patient and both parents' blood RNA samples suggested two different splicing patterns, and these two splicing patterns differed in the presence or absence of the first codon of exon 27, thus providing two splicing products designated as isoforms A and B, respectively. Furthermore, the proportions of these two patterns varied between the patient and either parent. A minigene assay further confirmed that the c.2967-1G>T variant led to the absence of isoform A (including the first codon of exon 27). The finding of our study demonstrates this variant, c.2967-1G>T, disrupts the balance of an alternative splice event which involves the use of two tandem alternatives acceptors and is not associated with typical symptoms of tuberous sclerosis. Our finding is of importance for genetic counseling and suggests that we need to be vigilant to avoid misdiagnosis when we encounter such a site.
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15
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Wang W, Zhao Y, Wang X, Wang Z, Cai Y, Li H, Zhang Y. Analysis of renal lesions in Chinese tuberous sclerosis complex patients with different types of TSC gene mutations. Genet Mol Biol 2022; 45:e20200387. [PMID: 35638823 PMCID: PMC9152844 DOI: 10.1590/1678-4685-gmb-2020-0387] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 03/16/2022] [Indexed: 12/17/2022] Open
Affiliation(s)
- Wenda Wang
- Chinese Academy of Medical Sciences and Peking Union Medical College, China
| | - Yang Zhao
- Chinese Academy of Medical Sciences and Peking Union Medical College, China
| | - Xu Wang
- Chinese Academy of Medical Sciences and Peking Union Medical College, China
| | - Zhan Wang
- Chinese Academy of Medical Sciences and Peking Union Medical College, China
| | - Yi Cai
- Central South University, China
| | - Hanzhong Li
- Chinese Academy of Medical Sciences and Peking Union Medical College, China
| | - Yushi Zhang
- Chinese Academy of Medical Sciences and Peking Union Medical College, China
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16
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Álvaro-Sánchez S, Abreu-Rodríguez I, Abulí A, Serra-Juhe C, Garrido-Navas MDC. Current Status of Genetic Counselling for Rare Diseases in Spain. Diagnostics (Basel) 2021; 11:2320. [PMID: 34943558 PMCID: PMC8700506 DOI: 10.3390/diagnostics11122320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/05/2021] [Accepted: 12/06/2021] [Indexed: 12/29/2022] Open
Abstract
Genetic Counselling is essential for providing personalised information and support to patients with Rare Diseases (RD). Unlike most other developed countries, Spain does not recognize geneticists or genetic counsellors as healthcare professionals Thus, patients with RD face not only challenges associated with their own disease but also deal with lack of knowledge, uncertainty, and other psychosocial issues arising as a consequence of diagnostic delay. In this review, we highlight the importance of genetic counsellors in the field of RD as well as evaluate the current situation in which rare disease patients receive genetic services in Spain. We describe the main units and strategies at the national level assisting patients with RD and we conclude with a series of future perspectives and unmet needs that Spain should overcome to improve the management of patients with RD.
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Affiliation(s)
| | - Irene Abreu-Rodríguez
- Genetics Service, Hospital del Mar Research Institute, IMIM, 08003 Barcelona, Spain;
| | - Anna Abulí
- Department of Clinical and Molecular Genetics, Hospital Vall d’Hebron, 08035 Barcelona, Spain;
- Medicine Genetics Group, Vall d’Hebron Research Institute (VHIR), 08035 Barcelona, Spain
| | - Clara Serra-Juhe
- U705 CIBERER, Genetics Department, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain;
- Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), 28029 Madrid, Spain
| | - Maria del Carmen Garrido-Navas
- CONGEN, Genetic Counselling Services, C/Albahaca 4, 18006 Granada, Spain;
- Genetics Department, Faculty of Sciences, Universidad de Granada, 18071 Granada, Spain
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17
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Ebrahimi-Fakhari D, Stires G, Hahn E, Krueger D, Franz DN. Prenatal Sirolimus Treatment for Rhabdomyomas in Tuberous Sclerosis. Pediatr Neurol 2021; 125:26-31. [PMID: 34624607 DOI: 10.1016/j.pediatrneurol.2021.09.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 08/10/2021] [Accepted: 09/20/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND In tuberous sclerosis, most cardiac rhabdomyomas regress spontaneously. In some cases, the tumors can cause life-threatening hemodynamic compromise requiring subsequent surgical resection. The mechanistic target of rapamycin inhibitors everolimus and sirolimus have shown to be effective treatments for multiple conditions. There are four reports of off-label treatment with transplacental sirolimus for fetal rhabdomyomas due to tuberous sclerosis complex. The optimal dosing regimen is unknown. METHODS We reviewed the medical records of all patients treated prenatally with sirolimus for rhabdomyomas. All fetuses had a clinical and molecular diagnosis of tuberous sclerosis complex (2012 Consensus Diagnostic Criteria, including a positive genetic test). Clinical history, mechanistic target of rapamycin inhibitor dosing and levels, outcome, and adverse events were reviewed after initiation of sirolimus treatment. RESULTS Three fetuses were treated with maternal sirolimus. Dosing regimens and subsequent trough levels differed from 1 mg/day to 6 mg/day and <1.0 ng/mL to 12.2 ng/mL. Cardiac rhabdomyomas gradually shrank in all patients. Growth restriction was noted in one patient. No severe adverse events occurred during the treatment period. CONCLUSIONS Maternal sirolimus appears to be a safe treatment option in prenatally detected rhabdomyomas with possible need for intervention. Follow-up visits with fetal ultrasound, echocardiography, and laboratory work should be performed weekly during the treatment period. The optimal dosing and trough level timepoints remain unclear. Based on our results, we recommend a sirolimus starting dose of at least 2 mg/m2/day, preferably 3-3.5 mg/m2/day to achieve a target trough level of 10-12 ng/mL.
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Affiliation(s)
- Daniel Ebrahimi-Fakhari
- Division of Neurology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of General Pediatrics, University Children's Hospital Muenster, Muenster, Germany.
| | - Gabrielle Stires
- Division of Neurology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Eunice Hahn
- The Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Darcy Krueger
- Division of Neurology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - David Neal Franz
- Division of Neurology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
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18
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Zhou Y, Wang X, Wang J, Ding Y, Wang Y, Li H, Zhao R, Wu B. Identification of TSC2 mosaic mutation limited to cortical tuber with TSC targeted sequencing: a case report and literature review. Childs Nerv Syst 2021; 37:3945-3949. [PMID: 33517515 DOI: 10.1007/s00381-021-05059-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 01/22/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Tuberous sclerosis complex (TSC) is an autosomal dominant disorder, mainly in childhood presents epilepsy due to cortical tubers. TSC1/TSC2 pathogenic variants cannot be detected in regular molecular genetic testing in around 10-15% of TSC patients. METHODS We analyzed TSC genes in both cortical tuber, blood and skin samples from a pediatric patient with refractory epilepsy. RESULTS We found no germline mutations by whole-exome sequencing. Well in targeted sequencing of TSC1/2 data, we identified de novo mutations only in cortical tuber: TSC2 NM_000548.5: exon34:c.4183C>T (p.Gln1395*) in 3% of the alleles. No other TSC mutations were found in patient's blood and skin samples and her parents' blood sample. CONCLUSION Our case report found TSC2 mosaic mutations can be only limited to cortical tuber in patients with TSC.
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Affiliation(s)
- Yuanfeng Zhou
- Department of Neurology, Children's Hospital of Fudan University, No.399, Wanyuan Road, Shanghai, 201102, China
| | - Xinhua Wang
- Department of Neurology, Children's Hospital of Fudan University, No.399, Wanyuan Road, Shanghai, 201102, China
| | - Ji Wang
- Department of Neurology, Children's Hospital of Fudan University, No.399, Wanyuan Road, Shanghai, 201102, China
| | - Yifeng Ding
- Department of Neurology, Children's Hospital of Fudan University, No.399, Wanyuan Road, Shanghai, 201102, China
| | - Yi Wang
- Department of Neurology, Children's Hospital of Fudan University, No.399, Wanyuan Road, Shanghai, 201102, China
| | - Hao Li
- Department of Neurosurgery, Children's Hospital of Fudan University, No.399, Wanyuan Road, Shanghai, 201102, China
| | - Rui Zhao
- Department of Neurosurgery, Children's Hospital of Fudan University, No.399, Wanyuan Road, Shanghai, 201102, China.
| | - Bingbing Wu
- The Molecular Genetic Diagnosis Center, Shanghai Key Lab of Birth Defects, Pediatrics Research Institute, Children's Hospital of Fudan University, No.399, Wanyuan Road, Shanghai, 201102, China.
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19
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Miszewska D, Sugalska M, Jóźwiak S. Risk Factors Associated with Refractory Epilepsy in Patients with Tuberous Sclerosis Complex: A Systematic Review. J Clin Med 2021; 10:jcm10235495. [PMID: 34884198 PMCID: PMC8658289 DOI: 10.3390/jcm10235495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Epilepsy affects 70-90% of patients with tuberous sclerosis complex (TSC). In one-third of them, the seizures become refractory to treatment. Drug-resistant epilepsy (DRE) carries a significant educational, social, cognitive, and economic burden. Therefore, determining risk factors that increase the odds of refractory seizures is needed. We reviewed current data on risk factors associated with DRE in patients with tuberous sclerosis. METHODS The review was performed according to the PRISMA guidelines. Embase, Cochrane Library, MEDLINE, and ClinicalTrial.gov databases were searched. Only full-text journal articles on patients with TSC which defined risk factors related to DRE were included. RESULTS Twenty articles were identified, with a cohort size between 6 and 1546. Seven studies were prospective. Three factors appear to significantly increase DRE risk: TSC2 mutation, infantile spasms, and a high number of cortical tubers. CONCLUSIONS A proper MRI and EEG monitoring, along with genetic testing, and close observation of individuals with early onset of seizures, allow identification of the patients at risk of DRE.
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20
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Iyer RR, Strahle JM, Groves ML. Neurosurgical Considerations of Neurocutaneous Syndromes. Neurosurg Clin N Am 2021; 33:81-89. [PMID: 34801145 DOI: 10.1016/j.nec.2021.09.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The phakomatoses are a group of genetic and acquired disorders characterized by neurologic, cutaneous, and often ocular manifestations, thus commonly referred to as neurocutaneous syndromes. In several of these conditions the underlying genetic pathophysiology has been elucidated, which will continue to play an important role in advancing therapeutic techniques. This article focuses on several examples of such neurocutaneous syndromes, with special attention to the relevant neurosurgical considerations of these patients.
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Affiliation(s)
- Rajiv R Iyer
- Department of Neurosurgery/Division of Pediatric Neurosurgery, University of Utah/Primary Children's Hospital, 100 N. Mario Capecchi Drive Suite 3850, Salt Lake City, UT 84113, USA.
| | - Jennifer M Strahle
- Pediatric Neuro Spine Program, Pediatric Cerebrovascular Surgery, Division of Pediatric Neurosurgery, Department of Neurosurgery, Washington University School of Medicine, 1 Childrens Pl Suite 4S20, St. Louis, MO 63110, USA
| | - Mari L Groves
- Department of Neurosurgery, Johns Hopkins School of Medicine, 600 N. Wolfe Street Phipps 554, Baltimore, MD 21287, USA
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21
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Cohen R, Genizi J, Korenrich L. Behavioral Symptoms May Correlate With the Load and Spatial Location of Tubers and With Radial Migration Lines in Tuberous Sclerosis Complex. Front Neurol 2021; 12:673583. [PMID: 34744957 PMCID: PMC8570125 DOI: 10.3389/fneur.2021.673583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 09/21/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: Tuberous sclerosis complex (TSC) is a multisystem neurocutaneous genetic disorder. The clinical manifestations are extensive and include neurological, dermatological, cardiac, ophthalmic, nephrological, and neuropsychiatric manifestations. The prediction and pathophysiology of neuropsychiatric disorders such as emotional symptoms, conduct problems, hyperactivity, and poor social behavior are poorly understood. The aim of the study was to diagnose neuropsychiatric symptoms in individuals with TSC, and to examine their possible correlations with quantity, magnitude, and spatial location of tubers and radial migration (RM) lines. Methods: The cohort comprised 16 individuals with TSC, aged 5–29 years, with normal or low normal intelligence. The participants or their parents were requested to fill Strengths and Difficulties Questionnaire (SDQ) and the TAND (TSC-associated neuropsychiatric disorders) Checklist for assessment of their neuropsychiatric symptoms. Correlations were examined between these symptoms and the magnitude, quantities, and locations of tubers and white matter RM lines, as identified in T2/FLAIR brain MRI scans. Results: The SDQ score for peer relationship problems showed correlation with the tuber load (r = 0.52, p < 0.05). Tuber load and learning difficulties correlated significantly in the temporal and parietal area. Mood swings correlated with tubers in the parietal area (r = 0.529, p < 0.05). RM lines in the temporal area correlated with abnormal total SDQ (r = 0.51, p < 0.05). Anxiety and extreme shyness were correlated with RM lines in the parietal area, r = 0.513, p < 0.05 and r = 0.593, p < 0.05, respectively. Hyperactive/inattention correlated negatively with RM lines in the parietal area (r = −707, p < 0.01). Conclusions: These observations may lead to future studies for precise localization of neuropsychiatric symptoms, thereby facilitating directed therapy.
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Affiliation(s)
- Rony Cohen
- Department of Pediatric Neurology, Schneider Children's Medical Center of Israel, Petah Tikva, Israel.,NF1 and Other Neurocutaneous Disorders Clinic, Schneider Children's Medical Center of Israel, Petah Tikva, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Jacob Genizi
- Pediatric Neurology Unit, Bnai Zion Medical Center, Haifa, Israel
| | - Liora Korenrich
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Department of Imaging, Schneider Children's Medical Center of Israel, Petah Tikva, Israel
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22
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Specchio N, Di Micco V, Trivisano M, Ferretti A, Curatolo P. The epilepsy-autism spectrum disorder phenotype in the era of molecular genetics and precision therapy. Epilepsia 2021; 63:6-21. [PMID: 34741464 DOI: 10.1111/epi.17115] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 10/20/2021] [Accepted: 10/20/2021] [Indexed: 11/30/2022]
Abstract
Autism spectrum disorder (ASD) is frequently associated with infants with epileptic encephalopathy, and early interventions targeting social and cognitive deficits can have positive effects on developmental outcome. However, early diagnosis of ASD among infants with epilepsy is complicated by variability in clinical phenotypes. Commonality in both biological and molecular mechanisms have been suggested between ASD and epilepsy, such as occurs with tuberous sclerosis complex. This review summarizes the current understanding of causal mechanisms between epilepsy and ASD, with a particularly genetic focus. Hypothetical explanations to support the conjugation of the two conditions include abnormalities in synaptic growth, imbalance in neuronal excitation/inhibition, and abnormal synaptic plasticity. Investigation of the probable genetic basis has implemented many genes, although the main risk supports existing hypotheses in that these cluster to abnormalities in ion channels, synaptic function and structure, and transcription regulators, with the mammalian target of rapamycin (mTOR) pathway and "mTORpathies" having been a notable research focus. Experimental models not only have a crucial role in determining gene functions but are also useful instruments for tracing disease trajectory. Precision medicine from gene therapy remains a theoretical possibility, but more contemporary developments continue in molecular tests to aid earlier diagnoses and better therapeutic targeting.
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Affiliation(s)
- Nicola Specchio
- Rare and Complex Epilepsy Unit, Division of Neurology, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Full Member of European Reference Network EpiCARE, Rome, Italy
| | - Valentina Di Micco
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University, Rome, Italy
| | - Marina Trivisano
- Rare and Complex Epilepsy Unit, Division of Neurology, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Full Member of European Reference Network EpiCARE, Rome, Italy
| | - Alessandro Ferretti
- Rare and Complex Epilepsy Unit, Division of Neurology, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Full Member of European Reference Network EpiCARE, Rome, Italy
| | - Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University, Rome, Italy
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23
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Updated International Tuberous Sclerosis Complex Diagnostic Criteria and Surveillance and Management Recommendations. Pediatr Neurol 2021; 123:50-66. [PMID: 34399110 DOI: 10.1016/j.pediatrneurol.2021.07.011] [Citation(s) in RCA: 213] [Impact Index Per Article: 71.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 07/20/2021] [Indexed: 01/10/2023]
Abstract
BACKGROUND Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disease affecting multiple body systems with wide variability in presentation. In 2013, Pediatric Neurology published articles outlining updated diagnostic criteria and recommendations for surveillance and management of disease manifestations. Advances in knowledge and approvals of new therapies necessitated a revision of those criteria and recommendations. METHODS Chairs and working group cochairs from the 2012 International TSC Consensus Group were invited to meet face-to-face over two days at the 2018 World TSC Conference on July 25 and 26 in Dallas, TX, USA. Before the meeting, working group cochairs worked with group members via e-mail and telephone to (1) review TSC literature since the 2013 publication, (2) confirm or amend prior recommendations, and (3) provide new recommendations as required. RESULTS Only two changes were made to clinical diagnostic criteria reported in 2013: "multiple cortical tubers and/or radial migration lines" replaced the more general term "cortical dysplasias," and sclerotic bone lesions were reinstated as a minor criterion. Genetic diagnostic criteria were reaffirmed, including highlighting recent findings that some individuals with TSC are genetically mosaic for variants in TSC1 or TSC2. Changes to surveillance and management criteria largely reflected increased emphasis on early screening for electroencephalographic abnormalities, enhanced surveillance and management of TSC-associated neuropsychiatric disorders, and new medication approvals. CONCLUSIONS Updated TSC diagnostic criteria and surveillance and management recommendations presented here should provide an improved framework for optimal care of those living with TSC and their families.
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Interleukin-6 mediates PSAT1 expression and serine metabolism in TSC2-deficient cells. Proc Natl Acad Sci U S A 2021; 118:2101268118. [PMID: 34544857 DOI: 10.1073/pnas.2101268118] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2021] [Indexed: 01/31/2023] Open
Abstract
Tuberous sclerosis complex (TSC) and lymphangioleiomyomatosis (LAM) are caused by aberrant mechanistic Target of Rapamycin Complex 1 (mTORC1) activation due to loss of either TSC1 or TSC2 Cytokine profiling of TSC2-deficient LAM patient-derived cells revealed striking up-regulation of Interleukin-6 (IL-6). LAM patient plasma contained increased circulating IL-6 compared with healthy controls, and TSC2-deficient cells showed up-regulation of IL-6 transcription and secretion compared to wild-type cells. IL-6 blockade repressed the proliferation and migration of TSC2-deficient cells and reduced oxygen consumption and extracellular acidification. U-13C glucose tracing revealed that IL-6 knockout reduced 3-phosphoserine and serine production in TSC2-deficient cells, implicating IL-6 in de novo serine metabolism. IL-6 knockout reduced expression of phosphoserine aminotransferase 1 (PSAT1), an essential enzyme in serine biosynthesis. Importantly, recombinant IL-6 treatment rescued PSAT1 expression in the TSC2-deficient, IL-6 knockout clones selectively and had no effect on wild-type cells. Treatment with anti-IL-6 (αIL-6) antibody similarly reduced cell proliferation and migration and reduced renal tumors in Tsc2 +/- mice while reducing PSAT1 expression. These data reveal a mechanism through which IL-6 regulates serine biosynthesis, with potential relevance to the therapy of tumors with mTORC1 hyperactivity.
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Kirby E, Elbashier S, Sweeney C, Twomey E, Gorman K, Riordan M, Awan A. Unexpected diagnosis in a child with hemolytic uremic syndrome: Answers. Pediatr Nephrol 2021; 36:2711-2714. [PMID: 33730282 DOI: 10.1007/s00467-021-05005-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 02/05/2021] [Indexed: 11/26/2022]
Affiliation(s)
- Eimear Kirby
- School of Medicine, Trinity College Dublin, University of Dublin, College Green, Dublin 2, Ireland.
| | - Shiraz Elbashier
- Department of Pediatric Nephrology, Temple Street Children's Hospital, Dublin, Ireland
| | - Clodagh Sweeney
- Department of Pediatric Nephrology, Temple Street Children's Hospital, Dublin, Ireland
| | - Eilish Twomey
- Department of Pediatric Radiology, Temple Street Children's Hospital, Dublin, Ireland
| | - Kathleen Gorman
- Department of Pediatric Neurology, Temple Street Children's Hospital, Dublin, Ireland
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - Michael Riordan
- Department of Pediatric Nephrology, Temple Street Children's Hospital, Dublin, Ireland
- Faculty of Medicine and Health Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Atif Awan
- Department of Pediatric Nephrology, Temple Street Children's Hospital, Dublin, Ireland
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
- Faculty of Medicine and Health Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
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Molecular-Genetic Characteristics and Genotype-Phenotype Correlations in Bulgarian Patients with Tuberous Sclerosis Complex. ACTA MEDICA BULGARICA 2021. [DOI: 10.2478/amb-2021-0020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Objective
The aim of the study was to determine the molecular-genetic characteristics of the autosomal dominant systematic disorder Tuberous Sclerosis Complex (TSC1 and TSC2) in Bulgarian patients and to derive some genotype-phenotype correlations.
Material and Methods
In total 42 patients/families with suspected clinical diagnosis of TSC were analyzed. We used direct sequencing and MLPA for the TSC1 and TSC2 gene analysis.
Results
In 38 families (90.5%) we confirmed the suspected clinical diagnosis – 15 with TSC1 (35.7%) and 23 (54.8%) with TSC2. In 4 families (9.5%) pathogenic variants were not found. In all 38 patients with proven diagnosis of TSC, we found 38 different mutations, 15 of which (39%) were detected for the first time by our research group. The mutation “hotspots“ in TSC1 gene are exons 9, 15, 17 and 18, where 73% of the TSC1 mutations are localized, while the TSC2 gene mutation “hotspots“ are exons 13 and 34, with 22% of the mutations situated there. In the TSC2 patients the common clinical findings include subcortical tubers, epilepsy with generalized tonic-clonic seizures, subependymal giant cell astrocytoma, facial angiofibromas, ungual fibromas, cardiac rhabdomyomas and renal angiomyolipomas, while in the TSC1 patients typically cortical tubers, cortical dysplasia and subependymal nodules were registered. In patients with aggressive frameshift and nonsense TSC1 and TSC2 mutations commonly hypomelanotic macules, cortical and subcortical tubers, cortical dysplasia, epilepsy with different types of seizures were found. Renal angiomyolipomas and cysts were detected mainly in patients with large deletions. Shagreen patches and intellectual disability were typically registered in equal degree in patients with frameshift, nonsense and missense mutations.
Conclusion
Although some genotype-phenotype correlations were derived, there is a great inter- and intrafamilial clinical variability in TSC, so it is impossible to predict the course of the disease on the basis of the detected molecular defect. The obtained results helped us to develop a diagnostic algorithm for proper molecular-genetic diagnostics which permits adequate genetic counseling, prophylaxis and treatment in the affected TSC families.
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Schubert-Bast S, Strzelczyk A. Review of the treatment options for epilepsy in tuberous sclerosis complex: towards precision medicine. Ther Adv Neurol Disord 2021; 14:17562864211031100. [PMID: 34349839 PMCID: PMC8290505 DOI: 10.1177/17562864211031100] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 06/21/2021] [Indexed: 12/24/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is a rare genetic disorder caused by mutations in the TSC1 or TSC2 genes, which encode proteins that antagonise the mammalian isoform of the target of rapamycin complex 1 (mTORC1) - a key mediator of cell growth and metabolism. TSC is characterised by the development of benign tumours in multiple organs, together with neurological manifestations including epilepsy and TSC-associated neuropsychiatric disorders (TAND). Epilepsy occurs frequently and is associated with significant morbidity and mortality; however, the management is challenging due to the intractable nature of the seizures. Preventative epilepsy treatment is a key aim, especially as patients with epilepsy may be at a higher risk of developing severe cognitive and behavioural impairment. Vigabatrin given preventatively reduces the risk and severity of epilepsy although the benefits for TAND are inconclusive. These promising results could pave the way for evaluating other treatments in a preventative capacity, especially those that may address the underlying pathophysiology of TSC, including everolimus, cannabidiol and the ketogenic diet (KD). Everolimus is an mTOR inhibitor approved for the adjunctive treatment of refractory TSC-associated seizures that has demonstrated significant reductions in seizure frequency compared with placebo, improvements that were sustained after 2 years of treatment. Highly purified cannabidiol, recently approved in the US as Epidiolex® for TSC-associated seizures in patients ⩾1 years of age, and the KD, may also participate in the regulation of the mTOR pathway. This review focusses on the pivotal clinical evidence surrounding these potential targeted therapies that may form the foundation of precision medicine for TSC-associated epilepsy, as well as other current treatments including anti-seizure drugs, vagus nerve stimulation and surgery. New future therapies are also discussed, together with the potential for preventative treatment with targeted therapies. Due to advances in understanding the molecular genetics and pathophysiology, TSC represents a prototypic clinical syndrome for studying epileptogenesis and the impact of precision medicine.
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Affiliation(s)
- Susanne Schubert-Bast
- Epilepsy Center Frankfurt Rhine-Main, Center of Neurology and Neurosurgery, Goethe-University Frankfurt, Frankfurt am Main, Germany
| | - Adam Strzelczyk
- Epilepsy Center Frankfurt Rhine-Main, Goethe-University Frankfurt, Schleusenweg 2-16, Frankfurt am Main, 60528, Germany
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Ding Y, Zhou Y, Yu L, Zhang L, Zhou S, Wang Y, Wang J. Correlation between epilepsy and genotype: A large retrospective tuberous sclerosis complex cohort. Seizure 2021; 91:273-277. [PMID: 34252879 DOI: 10.1016/j.seizure.2021.06.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/27/2021] [Accepted: 06/29/2021] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE To describe the first large population (n = 297) with tuberous sclerosis complex (TSC) in China and to examine the relationship between variants (type and location) and epilepsy. METHODS All exons and intron-exon boundaries of TSC1/TSC2 were sequenced with next-generation sequencing, and the distribution of several variants and associations between variant types and epilepsy were investigated. RESULTS Epilepsy occurred in 83.5% (248/297) of the individuals. The TSC1/TSC2 gene variant detection rate was 89.6% (266/297). The rate of epilepsy was significantly higher in the TSC2 group than in the TSC1 (p = 0.02) and no mutation identified (NMI) groups (p = 0.0005). TSC2 individuals are more likely to have spasms than TSC1 individuals (p =0.03). The age at epilepsy onset of individuals in the TSC2 group was younger than that of individuals in the TSC1 group (p = 0.008) and NMI group (p = 0.01). The age at epilepsy onset with truncated variants in the TSC1 group was significantly younger than that of individuals with nontruncated variants (p = 0.0001). The rate of epilepsy was significantly higher if variants occurred in the functional domain than in the nonfunctional domain in TSC2 individuals (p = 0.02). CONCLUSION This was the first large cohort study of the Chinese TSC population in which a comparative analysis of genotype and epilepsy was conducted. Individuals with TSC2 variants appeared to have more severe epileptic phenotypes, such as younger age at epilepsy onset, than those with TSC1 variants and NMI, and individuals with variants that occurred in TSC2 functional domains were more prone to epilepsy and had a younger age at epilepsy onset.
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Affiliation(s)
- Yifeng Ding
- Department of Neurology, Children's Hospital of Fudan University & National Children Medical Center, Shanghai 201102, China.
| | - Yuanfeng Zhou
- Department of Neurology, Children's Hospital of Fudan University & National Children Medical Center, Shanghai 201102, China
| | - Lifei Yu
- Department of Neurology, Children's Hospital of Fudan University & National Children Medical Center, Shanghai 201102, China
| | - Linmei Zhang
- Department of Neurology, Children's Hospital of Fudan University & National Children Medical Center, Shanghai 201102, China
| | - Shuizhen Zhou
- Department of Neurology, Children's Hospital of Fudan University & National Children Medical Center, Shanghai 201102, China
| | - Yi Wang
- Department of Neurology, Children's Hospital of Fudan University & National Children Medical Center, Shanghai 201102, China
| | - Ji Wang
- Department of Neurology, Children's Hospital of Fudan University & National Children Medical Center, Shanghai 201102, China.
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Renal tumors in tuberous sclerosis complex. Pediatr Nephrol 2021; 36:1427-1438. [PMID: 33006051 DOI: 10.1007/s00467-020-04775-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 08/11/2020] [Accepted: 09/10/2020] [Indexed: 01/19/2023]
Abstract
Tuberous sclerosis complex (TSC) is a multisystem hereditary disorder characterized by the growth of benign tumors (hamartomas) in multiple organs, including the kidneys. Renal angiomyolipomas (AML) are a major diagnostic feature of TSC and are present in the majority of patients by adulthood. However, AML are usually asymptomatic during childhood when neurological and developmental manifestations are the main source of morbidity. Kidney manifestations of TSC have historically been the main cause of morbidity and mortality of adults with TSC. The recognition that the complications of TSC are caused by dysregulation of the mammalian target of rapamycin (mTOR) pathway has led to an enormous progress in the management of patients with TSC in the last two decades, the establishment of diagnostic guidelines, and trials which have shown the therapeutic benefit of mTOR inhibitors. Kidney surveillance of children with TSC now provides the opportunity for timely interventions to reduce the impact of TSC in adulthood. In this review, we discuss the current management of kidney tumors associated with TSC, including the diagnosis, surveillance, and treatment options for these lesions. We also present outcome data from international registries demonstrating the effectiveness of the current management strategies. With clear management guidelines and efficient treatment of kidney tumors, we envisage that the long-term outcomes of patients with TSC will further improve in the future.
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Congenital subpendymal giant cell astrocytoma in children with tuberous sclerosis complex: growth patterns and neurological outcome. Pediatr Res 2021; 89:1447-1451. [PMID: 32516799 DOI: 10.1038/s41390-020-1002-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/21/2020] [Accepted: 05/27/2020] [Indexed: 11/08/2022]
Abstract
BACKGROUND Literature regarding congenital subependymal giant cell astrocytomas (SEGA) is limited, and suggests they are at risk of rapid growth and complications. We sought to characterise the growth patterns of congenital SEGA. The second part of the study was an exploratory analysis of congenital SEGA as a possible biomarker for poor neurological outcome. METHODS This single-centre case series describes ten patients with TSC who had SEGA diagnosed before 12 months. SEGA diameter and volumetric growth were analysed using serial MRIs. Neurological outcomes were compared to a genotype-matched group. RESULTS All children with congenital SEGA had a TSC2 mutation. Patients were followed for 1-8.7 years, during which median SEGA growth rate was 1.1 mm/yr in diameter or 150 mm3/yr volumetrically. SEGA with volume > 500 mm3 had a significantly higher growth rate compared with smaller SEGA (462 mm3/yr vs. 42 mm3/yr, p = 0.0095). Children with congenital SEGA had a high prevalence of severe epilepsy, developmental disability and autism spectrum disorder. CONCLUSION Congenital SEGA can follow a relatively benign course with a lower growth rate compared with published literature. Frequent neuroimaging surveillance is recommended for congenital SEGA with volumes exceeding 500 mm3. IMPACT Congenital SEGA occur in 9.2% of paediatric patients with tuberous sclerosis complex. There are few published cases of congenital SEGA to date. This case series of ten patients adds our experience seen in a tertiary referral hospital over 10 years. Congenital SEGA can follow a relatively benign course with a lower growth rate compared with published literature. Congenital SEGA with volume exceeding 500 mm3 had a significantly higher growth rate compared with smaller SEGA and should have more frequent neuroimaging surveillance.
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Suzuki M, Kondo A, Ogino I, Akiyama O, Fujita N, Shimizu Y, Arai H. A case of solitary subependymal giant cell astrocytoma with histopathological anaplasia and TSC2 gene alteration. Childs Nerv Syst 2021; 37:1357-1362. [PMID: 32725466 DOI: 10.1007/s00381-020-04839-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 07/24/2020] [Indexed: 11/24/2022]
Abstract
We report a case of subependymal giant cell astrocytoma (SEGA) with anaplastic histological features in a 3-year-old girl. She had no clinical manifestations of tuberous sclerosis complex (TSC) and no relevant family history. A few cases have been reported in which patients with SEGA had no other clinical manifestations of TSC (solitary SEGA). Genetic analysis using a blood sample from the patient showed no germline alterations in TSC1 or TSC2 genes, while the tumor tissue exhibited loss of heterozygosity (LOH) in TSC2. SEGAs are benign, slowly growing tumors that rarely have significant mitotic activity. However, histopathological examination in the present case revealed high mitotic activity and necrosis besides the typical large plump cells arranged in sheets. This may be the first genetically proven case of a solitary SEGA with histopathological anaplastic features. In this report, we reviewed solitary SEGAs and histopathological malignancy in SEGA.
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Affiliation(s)
- Mario Suzuki
- Department of Neurosurgery, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, Japan
| | - Akihide Kondo
- Department of Neurosurgery, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, Japan.
| | - Ikuko Ogino
- Department of Neurosurgery, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, Japan
| | - Osamu Akiyama
- Department of Neurosurgery, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, Japan
| | - Naohide Fujita
- Department of Neurosurgery, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, Japan
| | - Yuzaburo Shimizu
- Department of Neurosurgery, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, Japan
| | - Hajime Arai
- Department of Neurosurgery, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, Japan
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Torra R, Furlano M, Ortiz A, Ars E. Genetic kidney diseases as an underrecognized cause of chronic kidney disease: the key role of international registry reports. Clin Kidney J 2021; 14:1879-1885. [PMID: 34345410 PMCID: PMC8323147 DOI: 10.1093/ckj/sfab056] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Indexed: 01/01/2023] Open
Abstract
Inherited kidney diseases (IKDs) are among the leading causes of early-onset chronic kidney disease (CKD) and are responsible for at least 10-15% of cases of kidney replacement therapy (KRT) in adults. Paediatric nephrologists are very aware of the high prevalence of IKDs among their patients, but this is not the case for adult nephrologists. Recent publications have demonstrated that monogenic diseases account for a significant percentage of adult cases of CKD. A substantial number of these patients have received a non-specific/incorrect diagnosis or a diagnosis of CKD of unknown aetiology, which precludes correct treatment, follow-up and genetic counselling. There are a number of reasons why genetic kidney diseases are difficult to diagnose in adulthood: (i) adult nephrologists, in general, are not knowledgeable about IKDs; (ii) existence of atypical phenotypes; (iii) genetic testing is not universally available; (iv) family history is not always available or may be negative; (v) lack of knowledge of various genotype-phenotype relationships and (vi) conflicting interpretation of the pathogenicity of many sequence variants. Registries can contribute to visualize the burden of IKDs by regularly grouping all IKDs in their annual reports, as is done for glomerulonephritis or interstitial diseases, rather than reporting only cystic disease and hiding other IKDs under labels such as 'miscellaneous' or 'other'. Any effort to reduce the percentage of patients needing KRT with a diagnosis of 'nephropathy of unknown etiology' or an unspecific/incorrect diagnosis should be encouraged as a step towards precision nephrology. Genetic testing may be of value in this context but should not be used indiscriminately, but rather on the basis of a deep knowledge of IKDs.
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Affiliation(s)
- Roser Torra
- Department of Nephrology, Inherited Kidney Diseases, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau (IIB-Sant Pau), Medicine Department-Universitat Autónoma de Barcelona, REDinREN, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Mónica Furlano
- Department of Nephrology, Inherited Kidney Diseases, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau (IIB-Sant Pau), Medicine Department-Universitat Autónoma de Barcelona, REDinREN, Instituto de Investigación Carlos III, Barcelona, Spain
| | - Alberto Ortiz
- IIS-Fundación Jimenez Diaz, School of Medicine, Universidad Autónoma de Madrid, Fundación Renal Iñigo Alvarez de Toledo-IRSIN, REDinREN, Instituto de Investigación Carlos III, Madrid, Spain
| | - Elisabet Ars
- Molecular Biology Laboratory, Fundació Puigvert, Instituto de Investigaciones Biomédicas Sant Pau (IIB-Sant Pau), Universitat Autónoma de Barcelona, REDinREN, Instituto de Investigación Carlos III, Barcelona, Spain
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Ikeda KM, House AA, Connaughton DM, Pautler SE, Siu VM, Jones ML. Potential Pitfalls in Pre-implantation Genetic Diagnosis in a Patient with Tuberous Sclerosis and Isolated Mosaicism for a TSC2 Variant in Renal Tissue. Mol Syndromol 2021; 12:154-158. [PMID: 34177431 DOI: 10.1159/000513326] [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: 08/14/2020] [Accepted: 11/24/2020] [Indexed: 11/19/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant disorder that displays a wide spectrum of clinical manifestations, often affecting multiple organs including the kidneys, brain, lungs, and skin. A pathogenic mutation in either the TSC1 or TSC2 gene can be detected in almost 85% of the cases, with mosaicism accounting for about half of the remaining cases. We report a case of TSC diagnosed clinically, requesting genetic counselling regarding reproductive risks. No mutation was identified on initial testing of peripheral blood; however, mosaicism for a likely pathogenic frameshift variant in TSC2 was detected at a level of 15% in renal angiomyolipoma tissue. Despite widespread clinical manifestations of TCS, this variant was not detected in skin fibroblasts or saliva, raising the possibility this is an isolated somatic mutation in renal tissue with the underlying germline mutation not yet identified. This case highlights the difficulties when counselling patients with mosaicism regarding their reproductive risks and prenatal diagnostic options.
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Affiliation(s)
- Kristin M Ikeda
- Department of Clinical Neurological Sciences, London Health Sciences Centre, London, Ontario, Canada.,Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Andrew A House
- Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.,Division of Nephrology, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada
| | - Dervla M Connaughton
- Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.,Division of Nephrology, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada
| | - Stephen E Pautler
- Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.,Department of Surgery, London Health Sciences Centre, London, Ontario, Canada
| | - Victoria Mok Siu
- Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.,Division of Medical Genetics, Department of Pediatrics, London Health Sciences Centre, London, Ontario, Canada
| | - Michelle-Lee Jones
- Department of Clinical Neurological Sciences, London Health Sciences Centre, London, Ontario, Canada.,Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
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A Rare Soft-Tissue Tumor in a 15-Year-Old Boy With Tuberous Sclerosis Complex: Answer. Am J Dermatopathol 2021; 42:460. [PMID: 32433318 DOI: 10.1097/dad.0000000000001387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Cartron AM, Buccine D, Treichel AM, Lee CR, Moss J, Darling TN. Miliary fibromas in tuberous sclerosis complex. J Eur Acad Dermatol Venereol 2021; 35:1226-1229. [PMID: 33565654 DOI: 10.1111/jdv.17161] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 01/27/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND Tuberous sclerosis complex (TSC) is a hamartoma syndrome characterized by multiple skin lesions, such as angiofibromas, shagreen patch and miliary fibromas (MiF). OBJECTIVE To determine the clinical and histological features of MiF. METHODS A retrospective analysis was conducted on 133 adults with TSC. Photography was used to characterize the appearance and location of MiF. Histological features in five skin samples from four individuals were evaluated by a board-certified dermatopathologist. RESULTS MiF were observed in 19 of 133 (14%) individuals with TSC. MiF were 1- to 3-mm skin-coloured, sessile papules scattered on the back and rarely buttocks or thighs. Most were scattered in a bilaterally symmetric distribution, but others were asymmetric or associated with a shagreen patch. Histological features of MiF included expansion of the papillary and periadnexal dermis with variable hamartomatous abnormalities involving adjacent epithelial components. CONCLUSIONS MiF are distinct from other cutaneous lesions in TSC such as shagreen patches and angiofibromas. Recognition of this entity is important in defining the spectrum of TSC disease and reassuring individuals with TSC that these lesions are benign.
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Affiliation(s)
- A M Cartron
- Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.,Department of Dermatology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - D Buccine
- Department of Dermatology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - A M Treichel
- Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.,Department of Dermatology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - C R Lee
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - J Moss
- Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - T N Darling
- Department of Dermatology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
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Swietlik EM, Prapa M, Martin JM, Pandya D, Auckland K, Morrell NW, Gräf S. 'There and Back Again'-Forward Genetics and Reverse Phenotyping in Pulmonary Arterial Hypertension. Genes (Basel) 2020; 11:E1408. [PMID: 33256119 PMCID: PMC7760524 DOI: 10.3390/genes11121408] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 11/17/2020] [Accepted: 11/23/2020] [Indexed: 02/07/2023] Open
Abstract
Although the invention of right heart catheterisation in the 1950s enabled accurate clinical diagnosis of pulmonary arterial hypertension (PAH), it was not until 2000 when the landmark discovery of the causative role of bone morphogenetic protein receptor type II (BMPR2) mutations shed new light on the pathogenesis of PAH. Since then several genes have been discovered, which now account for around 25% of cases with the clinical diagnosis of idiopathic PAH. Despite the ongoing efforts, in the majority of patients the cause of the disease remains elusive, a phenomenon often referred to as "missing heritability". In this review, we discuss research approaches to uncover the genetic architecture of PAH starting with forward phenotyping, which in a research setting should focus on stable intermediate phenotypes, forward and reverse genetics, and finally reverse phenotyping. We then discuss potential sources of "missing heritability" and how functional genomics and multi-omics methods are employed to tackle this problem.
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Affiliation(s)
- Emilia M. Swietlik
- Department of Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; (E.M.S.); (M.P.); (J.M.M.); (D.P.); (K.A.); (N.W.M.)
- Royal Papworth Hospital NHS Foundation Trust, Cambridge CB2 0AY, UK
- Addenbrooke’s Hospital NHS Foundation Trust, Cambridge CB2 0QQ, UK
| | - Matina Prapa
- Department of Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; (E.M.S.); (M.P.); (J.M.M.); (D.P.); (K.A.); (N.W.M.)
- Addenbrooke’s Hospital NHS Foundation Trust, Cambridge CB2 0QQ, UK
| | - Jennifer M. Martin
- Department of Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; (E.M.S.); (M.P.); (J.M.M.); (D.P.); (K.A.); (N.W.M.)
| | - Divya Pandya
- Department of Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; (E.M.S.); (M.P.); (J.M.M.); (D.P.); (K.A.); (N.W.M.)
| | - Kathryn Auckland
- Department of Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; (E.M.S.); (M.P.); (J.M.M.); (D.P.); (K.A.); (N.W.M.)
| | - Nicholas W. Morrell
- Department of Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; (E.M.S.); (M.P.); (J.M.M.); (D.P.); (K.A.); (N.W.M.)
- Royal Papworth Hospital NHS Foundation Trust, Cambridge CB2 0AY, UK
- Addenbrooke’s Hospital NHS Foundation Trust, Cambridge CB2 0QQ, UK
- NIHR BioResource for Translational Research, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK
| | - Stefan Gräf
- Department of Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; (E.M.S.); (M.P.); (J.M.M.); (D.P.); (K.A.); (N.W.M.)
- NIHR BioResource for Translational Research, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK
- Department of Haematology, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0PT, UK
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Marom D. Genetics of tuberous sclerosis complex: an update. Childs Nerv Syst 2020; 36:2489-2496. [PMID: 32761379 DOI: 10.1007/s00381-020-04726-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 06/03/2020] [Indexed: 10/23/2022]
Abstract
PURPOSE To review the current genetic aspects of tuberous sclerosis complex. METHODS Review of the literature. RESULTS Tuberous sclerosis complex (TSC), a long known childhood-onset monogenic disorder, characterized by hamartoma formation affecting mainly the brain, heart, kidney, lung, and skin, is associated with a high morbidity burden and risk of a reduced life span. The identification of TSC1 and TSC2, as tumor suppressor genes causative of the disorder, led to the elucidation of the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway and its pivotal role in the pathogenesis of hamartoma formation. This knowledge was translated into standard clinical practice with the discovery of rapamycin, and additional analogues, as inhibitors of mTORC1. CONCLUSION Next-generation sequencing was proven to be fundamental to drive research of tumorigenesis in TSC, hopefully leading to new therapeutic options in the future.
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Affiliation(s)
- Daphna Marom
- Human Genetics Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel. .,Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
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Sandoval Karamian AG. 50 Years Ago in The Journal of Pediatrics: Tuberous Sclerosis: From Phenotype to Genotype. J Pediatr 2020; 225:64. [PMID: 32977871 DOI: 10.1016/j.jpeds.2020.04.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Uchiyama H, Masunaga Y, Ishikawa T, Fukuoka T, Fukami M, Saitsu H, Ogata T. TSC1 intragenic deletion transmitted from a mosaic father to two siblings with cardiac rhabdomyomas: Identification of two aberrant transcripts. Eur J Med Genet 2020; 63:104060. [PMID: 32889144 DOI: 10.1016/j.ejmg.2020.104060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 08/10/2020] [Accepted: 08/31/2020] [Indexed: 10/23/2022]
Abstract
Tuberous sclerosis complex (TSC) is a rare autosomal dominant disorder characterized by non-cancerous tumors in multiple organs including the brain, kidney, lung, heart, and skin. We encountered a Japanese family consisting of two siblings (a four-year-old boy and a one-year-old girl) with multiple cardiac rhabdomyomas conveying a high risk of TSC and apparently unaffected sibling (a two-year-old girl) and parents. Whole exome sequencing and application of Integrative Genomic Viewer revealed an identical intragenic TSC1 deletion with the breakpoints on intron 15 and exon 19 in the affected siblings, but not in the apparently unaffected sibling and parents. Subsequently, PCR-based analyses were performed using primers flanking the deletion, showing that the deletion was also present in the father and that the deletion occurred between chr9:135,777,038 (bp) and chr9:135,780,540 (bp) in association with a one bp overlap. Furthermore, RT-PCR analyses were carried out using lymphoblastoid cell lines, revealing a major in-frame insertion/deletion transcript produced by aberrant splicing using a cryptic ″ag″ splice acceptor motif at intron 15 (r.1998_2438delinsTTCATTAGGTGG) and a minor frameshift transcript generated by aberrant splicing between exon 15 and exon 20 (r.1998_2502del, p.Lys666Asnfs*15) in the affected siblings. These findings imply that the intragenic deletion producing two aberrant transcripts was generated as a somatic pathogenic variant involving the germline in the father and was transmitted to the affected siblings.
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Affiliation(s)
- Hiroki Uchiyama
- Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Yohei Masunaga
- Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Takamichi Ishikawa
- Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Tetsuya Fukuoka
- Department of Pediatrics, Shizuoka Saiseikai General Hospital, Shizuoka, Japan
| | - Maki Fukami
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Hirotomo Saitsu
- Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Tsutomu Ogata
- Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu, Japan.
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40
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Kapfhamer D, McKenna J, Yoon CJ, Murray-Stewart T, Casero RA, Gambello MJ. Ornithine decarboxylase, the rate-limiting enzyme of polyamine synthesis, modifies brain pathology in a mouse model of tuberous sclerosis complex. Hum Mol Genet 2020; 29:2395-2407. [PMID: 32588887 PMCID: PMC7424721 DOI: 10.1093/hmg/ddaa121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 05/18/2020] [Accepted: 06/11/2020] [Indexed: 12/11/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is a rare autosomal dominant neurodevelopmental disorder characterized by variable expressivity. TSC results from inactivating variants within the TSC1 or TSC2 genes, leading to constitutive activation of mechanistic target of rapamycin complex 1 signaling. Using a mouse model of TSC (Tsc2-RG) in which the Tsc2 gene is deleted in radial glial precursors and their neuronal and glial descendants, we observed increased ornithine decarboxylase (ODC) enzymatic activity and concentration of its product, putrescine. To test if increased ODC activity and dysregulated polyamine metabolism contribute to the neurodevelopmental defects of Tsc2-RG mice, we used pharmacologic and genetic approaches to reduce ODC activity in Tsc2-RG mice, followed by histologic assessment of brain development. We observed that decreasing ODC activity and putrescine levels in Tsc2-RG mice worsened many of the neurodevelopmental phenotypes, including brain growth and neuronal migration defects, astrogliosis and oxidative stress. These data suggest a protective effect of increased ODC activity and elevated putrescine that modify the phenotype in this developmental Tsc2-RG model.
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Affiliation(s)
- David Kapfhamer
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia
| | - James McKenna
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia
| | - Caroline J Yoon
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia
| | - Tracy Murray-Stewart
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Robert A Casero
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Michael J Gambello
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia
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Gimpel C, Bergmann C, Brinkert F, Cetiner M, Gembruch U, Haffner D, Kemper M, König J, Liebau M, Maier RF, Oh J, Pape L, Riechardt S, Rolle U, Rossi R, Stegmann J, Vester U, Kaisenberg CV, Weber S, Schaefer F. [Kidney Cysts and Cystic Nephropathies in Children - A Consensus Guideline by 10 German Medical Societies]. KLINISCHE PADIATRIE 2020; 232:228-248. [PMID: 32659844 DOI: 10.1055/a-1179-0728] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This consensus-based guideline was developed by all relevant German pediatric medical societies. Ultrasound is the standard imaging modality for pre- and postnatal kidney cysts and should also exclude extrarenal manifestations in the abdomen and internal genital organs. MRI has selected indications. Suspicion of a cystic kidney disease should prompt consultation of a pediatric nephrologist. Prenatal management must be tailored to very different degrees of disease severity. After renal oligohydramnios, we recommend delivery in a perinatal center. Neonates should not be denied renal replacement therapy solely because of their age. Children with unilateral multicystic dysplastic kidney do not require routine further imaging or nephrectomy, but long-term nephrology follow-up (as do children with uni- or bilateral kidney hypo-/dysplasia with cysts). ARPKD (autosomal recessive polycystic kidney disease), nephronophthisis, Bardet-Biedl syndrome and HNF1B mutations cause relevant extrarenal disease and genetic testing is advisable. Children with tuberous sclerosis complex, tumor predisposition (e. g. von Hippel Lindau syndrome) or high risk of acquired kidney cysts should have regular ultrasounds. Even asymptomatic children of parents with ADPKD (autosomal dominant PKD) should be monitored for hypertension and proteinuria. Presymptomatic diagnostic ultrasound or genetic examination for ADPKD in minors should only be done after thorough counselling. Simple cysts are very rare in children and ADPKD in a parent should be excluded. Complex renal cysts require further investigation.
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Affiliation(s)
- Charlotte Gimpel
- Department of Internal Medicine IV, Medical Center - University of Freiburg, Freiburg.,Faculty of Medicine, University of Freiburg, Freiburg im Breisgau
| | - Carsten Bergmann
- Department of Internal Medicine IV, Medical Center - University of Freiburg, Freiburg.,Faculty of Medicine, University of Freiburg, Freiburg im Breisgau.,Medizinische Genetik Mainz, Limbach Genetics, Mainz
| | - Florian Brinkert
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg
| | - Metin Cetiner
- Department of Pediatrics II, University Hospital Essen, Essen
| | - Ulrich Gembruch
- Department of Obstetrics and Prenatal Medicine, University Hospital of Bonn, Bonn
| | - Dieter Haffner
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover
| | - Markus Kemper
- Department of Pediatrics, Asklepios Kliniken Hamburg GmbH, Asklepios Klinik Nord, Standort Heidberg, Hamburg
| | - Jens König
- Department of General Pediatrics, University Children's Hospital Münster, Münster
| | - Max Liebau
- Department of Pediatrics, University Hospital Cologne, Cologne.,Center for Molecular Medicine, University of Cologne, Cologne
| | - Rolf Felix Maier
- Department of Pediatrics, University Hospital of Giessen and Marburg, Campus Marburg, Marburg
| | - Jun Oh
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg
| | - Lars Pape
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover
| | - Silke Riechardt
- Department of Urology, University Medical Center Hamburg-Eppendorf, Hamburg
| | - Udo Rolle
- Department of Pediatric Surgery, Hospital of the Goethe University Frankfurt, Frankfurt am Main
| | - Rainer Rossi
- Department of Pediatrics, Vivantes Klinikum Neukölln, Berlin
| | - Joachim Stegmann
- Department of Radiology, Catholic Children's Hospital Wilhelmstift, Hamburg
| | - Udo Vester
- Department of Pediatrics, HELIOS Hospital Duisburg, Duisburg
| | - Constantin von Kaisenberg
- Department of Obstetrics and Gynaecology, Center for Perinatal Medicine, Hannover Medical School, Hannover
| | - Stefanie Weber
- Department of Pediatrics, University Hospital of Giessen and Marburg, Campus Marburg, Marburg
| | - Franz Schaefer
- Center for Pediatrics and Adolescent Medicine, Division of Pediatric Nephrology, University Hospital Heidelberg, Heidelberg
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Rosengren T, Nanhoe S, de Almeida LGD, Schönewolf-Greulich B, Larsen LJ, Hey CAB, Dunø M, Ek J, Risom L, Nellist M, Møller LB. Mutational analysis of TSC1 and TSC2 in Danish patients with tuberous sclerosis complex. Sci Rep 2020; 10:9909. [PMID: 32555378 PMCID: PMC7303179 DOI: 10.1038/s41598-020-66588-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 05/19/2020] [Indexed: 02/07/2023] Open
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by hamartomas in the skin and other organs, including brain, heart, lung, kidney and bones. TSC is caused by mutations in TSC1 and TSC2. Here, we present the TSC1 and TSC2 variants identified in 168 Danish individuals out of a cohort of 327 individuals suspected of TSC. A total of 137 predicted pathogenic or likely pathogenic variants were identified: 33 different TSC1 variants in 42 patients, and 104 different TSC2 variants in 126 patients. In 40 cases (24%), the identified predicted pathogenic variant had not been described previously. In total, 33 novel variants in TSC2 and 7 novel variants in TSC1 were identified. To assist in the classification of 11 TSC2 variants, we investigated the effects of these variants in an in vitro functional assay. Based on the functional results, as well as population and genetic data, we classified 8 variants as likely to be pathogenic and 3 as likely to be benign.
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Affiliation(s)
- Thomas Rosengren
- Clinical Genetics Clinic, Copenhagen University Hospital, Rigshospitalet. Address 1: Kennedy Center, Gl landevej 7, DK-2600, Glostrup, Denmark. Address 2: 4062, Blegdamsvej 9, DK-2100, Østerbro, Denmark
| | - Santoesha Nanhoe
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Luis Gustavo Dufner de Almeida
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands.,Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Bitten Schönewolf-Greulich
- Clinical Genetics Clinic, Copenhagen University Hospital, Rigshospitalet. Address 1: Kennedy Center, Gl landevej 7, DK-2600, Glostrup, Denmark. Address 2: 4062, Blegdamsvej 9, DK-2100, Østerbro, Denmark
| | - Lasse Jonsgaard Larsen
- Clinical Genetics Clinic, Copenhagen University Hospital, Rigshospitalet. Address 1: Kennedy Center, Gl landevej 7, DK-2600, Glostrup, Denmark. Address 2: 4062, Blegdamsvej 9, DK-2100, Østerbro, Denmark
| | - Caroline Amalie Brunbjerg Hey
- Clinical Genetics Clinic, Copenhagen University Hospital, Rigshospitalet. Address 1: Kennedy Center, Gl landevej 7, DK-2600, Glostrup, Denmark. Address 2: 4062, Blegdamsvej 9, DK-2100, Østerbro, Denmark
| | - Morten Dunø
- Clinical Genetics Clinic, Copenhagen University Hospital, Rigshospitalet. Address 1: Kennedy Center, Gl landevej 7, DK-2600, Glostrup, Denmark. Address 2: 4062, Blegdamsvej 9, DK-2100, Østerbro, Denmark
| | - Jakob Ek
- Clinical Genetics Clinic, Copenhagen University Hospital, Rigshospitalet. Address 1: Kennedy Center, Gl landevej 7, DK-2600, Glostrup, Denmark. Address 2: 4062, Blegdamsvej 9, DK-2100, Østerbro, Denmark
| | - Lotte Risom
- Clinical Genetics Clinic, Copenhagen University Hospital, Rigshospitalet. Address 1: Kennedy Center, Gl landevej 7, DK-2600, Glostrup, Denmark. Address 2: 4062, Blegdamsvej 9, DK-2100, Østerbro, Denmark
| | - Mark Nellist
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Lisbeth Birk Møller
- Clinical Genetics Clinic, Copenhagen University Hospital, Rigshospitalet. Address 1: Kennedy Center, Gl landevej 7, DK-2600, Glostrup, Denmark. Address 2: 4062, Blegdamsvej 9, DK-2100, Østerbro, Denmark.
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Goldman A. RAP-ALO(N)G and Make Me Smart. Epilepsy Curr 2020; 20:162-164. [PMID: 32550838 PMCID: PMC7281900 DOI: 10.1177/1535759720919467] [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] [Indexed: 11/30/2022] Open
Abstract
TSC Patient-Derived Isogenic Neural Progenitor Cells Reveal Altered Early
Neurodevelopmental Phenotypes and Rapamycin-Induced MNK-eIF4E Signaling Martin P, Wagh V, Reis SA, et al. Mol Autism. 2020;11:2.
doi:10.1186/s13229-019-0311-3. eCollection 2020. Background: Tuberous sclerosis complex (TSC) is a neurodevelopmental disorder with frequent
occurrence of epilepsy, autism spectrum disorder (ASD), intellectual disability
(ID), and tumors in multiple organs. The aberrant activation of mTORC1 in TSC has
led to treatment with mTORC1 inhibitor rapamycin as a lifelong therapy for tumors,
but TSC-associated neurocognitive manifestations remain unaffected by rapamycin. Methods: Here, we generated patient-specific, induced pluripotent stem cells (iPSCs) from a
patient with TSC with a heterozygous, germline, nonsense mutation in exon 15 of TSC1
and established an isogenic set of heterozygous (Het), null, and corrected wild-type
(Corr-WT) iPSCs using CRISPR/Cas9-mediated gene editing. We differentiated these
iPSCs into neural progenitor cells (NPCs) and examined neurodevelopmental
phenotypes, signaling, and changes in gene expression by RNA-seq. Results: Differentiated NPCs revealed enlarged cell size in TSC1-Het and Null NPCs,
consistent with mTORC1 activation. TSC1-Het and Null NPCs also revealed enhanced
proliferation and altered neurite outgrowth in a genotype-dependent manner, which
was not reversed by rapamycin. Transcriptome analyses of TSC1-NPCs revealed
differentially expressed genes that display a genotype-dependent linear response,
that is, genes upregulated/downregulated in Het were further increased/decreased in
Null. In particular, genes linked to ASD, epilepsy, and ID were significantly
upregulated or downregulated, warranting further investigation. In TSC1-Het and Null
NPCs, we also observed basal activation of ERK1/2, which was further activated upon
rapamycin treatment. Rapamycin also increased MNK1/2-eIF4E signaling in
TSC1-deficient NPCs. Conclusion: MEK-ERK and MNK-eIF4E pathways regulate protein translation, and our results
suggest that aberrant translation distinct in TSC1/2-deficient NPCs could play a
role in neurodevelopmental defects. Our data showing upregulation of these signaling
pathways by rapamycin support a strategy to combine an MEK or an MNK inhibitor with
rapamycin that may be superior for TSC-associated central nervous system defects.
Importantly, our generation of isogenic sets of NPCs from patients with TSC provides
a valuable platform for translatome and large-scale drug screening studies. Overall,
our studies further support the notion that early developmental events such as NPC
proliferation and initial process formation, such as neurite number and length that
occur prior to neuronal differentiation, represent primary events in neurogenesis
critical to disease pathogenesis of neurodevelopmental disorders such as ASD.
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Ebrahimi-Fakhari D, Franz DN. Pharmacological treatment strategies for subependymal giant cell astrocytoma (SEGA). Expert Opin Pharmacother 2020; 21:1329-1336. [PMID: 32338549 DOI: 10.1080/14656566.2020.1751124] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Subependymal ependymal giant cell astrocytomas (SEGAs) occur almost exclusively in the setting of tuberous sclerosis (TSC). They are low-grade gliomas which typically produce clinical symptoms through either mass effect or hydrocephalus. As do other manifestations of tuberous sclerosis, these lesions result from mutations in either the TSC1 or the TSC2 gene. These mutations cause hyperactivation of the mechanistic target of rapamycin (mTOR). In view of their tendency to grow slowly, clinical symptoms usually only occur when the tumors reach a considerable size. Therapy can involve surgical resection, cerebrospinal fluid diversion, or medical therapy with an mTOR inhibitor. AREAS COVERED Herein, the authors discuss the diagnosis, symptoms, and practical management of SEGAs as well as providing their expert opinion. EXPERT OPINION mTOR inhibitors have largely replaced surgery as the primary modality for the management of SEGAs. Surgical treatment is largely limited to tumors that present with acute hydrocephalus and increased intracranial pressure. Patients with TSC should undergo periodic screening with CT or preferably MRI scans of the brain from childhood to approximately age 25 to identify SEGAs which require treatment. In addition to avoiding potential morbidity associated with surgical resection, mTOR inhibitors have the potential to improve the clinical status of tuberous sclerosis patients generally.
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Affiliation(s)
- Daniel Ebrahimi-Fakhari
- Division of Neurology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center , Cincinnati, OH, USA.,Department of General Pediatrics, University Children's Hospital Muenster , Muenster, Germany
| | - David Neal Franz
- Division of Neurology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center , Cincinnati, OH, USA
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An update on the central nervous system manifestations of tuberous sclerosis complex. Acta Neuropathol 2020; 139:613-624. [PMID: 30976976 DOI: 10.1007/s00401-019-02003-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 04/01/2019] [Accepted: 04/02/2019] [Indexed: 12/17/2022]
Abstract
The autosomal dominant disorder tuberous sclerosis complex (TSC) is characterized by an array of manifestations both within and outside of the central nervous system (CNS), including hamartomas and other malformations. TSC is caused by mutations in the TSC1 or TSC2 gene resulting in activation of the mechanistic target of rapamycin (mTOR) signaling pathway. Study of TSC has shed light on the critical role of the mTOR pathway in neurodevelopment. This update reviews the genetic basis of TSC, its cardinal phenotypic CNS features, and recent developments in the field of TSC and other mTOR-altered disorders.
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Savini MN, Mingarelli A, Peron A, La Briola F, Cervi F, Alfano RM, Canevini MP, Vignoli A. Electro-clinical and neurodevelopmental outcome in six children with early diagnosis of tuberous sclerosis complex and role of the genetic background. Ital J Pediatr 2020; 46:36. [PMID: 32216820 PMCID: PMC7099780 DOI: 10.1186/s13052-020-0801-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 03/17/2020] [Indexed: 11/10/2022] Open
Abstract
Background Seizures in individuals affected by tuberous sclerosis complex (TSC) commonly develop in the first year of life, are often preceded by a progressive deterioration of the electroencephalogram (EEG), and likely influence developmental outcome. Although early diagnosis of TSC has offered a tremendous opportunity to monitor affected patients before seizure onset, reports of the neurological manifestations of TSC in infants before seizure onset are still scarce. Here we describe early EEG activity, clinical and genetic data and developmental assessment in a group of TSC infants, with the aim of identifying possible prognostic factors for neurodevelopmental outcome. Methods We report on six infants diagnosed with TSC pre- or perinatally, who underwent serial Video-EEG recordings during the first two years of life. EEGs were classified based on distribution and intensity of interictal epileptiform discharges, and Vigabatrin was introduced in case of ictal discharges. Psychomotor development, cognitive functioning and behavioral problems were assessed through standardized scales. Molecular testing included analysis for point mutations and deletions/duplications in TSC1 and TSC2. Results EEG abnormalities appeared at a mean age of 4 months. Four of the six patients developed seizures. EEG abnormalities preceded the onset of clinical seizures in all of them. The two individuals with good seizure control showed normal development, while the other two exhibited psychomotor delays. The patients who did not develop seizures had normal development. A pathogenic variant in the TSC2 gene was detected in all patients but one. The one without a mutation identified did not develop seizures and showed normal neurodevelopment. Of note, the two patients presenting with the worst outcome (that is, poor seizure control and intellectual/behavioral disability) both carried pathogenic variants in the GAP domain of TSC2. Conclusion Our report supports the importance of EEG monitoring before seizure onset in patients with TSC, and the correlation between prompt seizure control and positive neurodevelopmental outcome, regardless of seizure type. Our results also indicate a possible role of the genetic background in influencing the outcome.
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Affiliation(s)
- M N Savini
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Via di Rudinì 8, 20142, Milan, Italy
| | - A Mingarelli
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy
| | - A Peron
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Via di Rudinì 8, 20142, Milan, Italy. .,Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA. .,Human Pathology and Molecular Pathology Unit, San Paolo Hospital, Milan, Italy.
| | - F La Briola
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy
| | - F Cervi
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy
| | - R M Alfano
- Human Pathology and Molecular Pathology Unit, San Paolo Hospital, Milan, Italy
| | - M P Canevini
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Via di Rudinì 8, 20142, Milan, Italy
| | - A Vignoli
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Via di Rudinì 8, 20142, Milan, Italy
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Moog U, Felbor U, Has C, Zirn B. Disorders Caused by Genetic Mosaicism. DEUTSCHES ARZTEBLATT INTERNATIONAL 2020; 116:119-125. [PMID: 32181732 PMCID: PMC7081367 DOI: 10.3238/arztebl.2020.0119] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 04/23/2019] [Accepted: 11/28/2019] [Indexed: 02/03/2023]
Abstract
BACKGROUND Genetic mosaics arise through new mutations occurring after fertiliza- tion (i.e., postzygotic mutations). Mosaics have been described in recent years as the cause of many different disorders; many of these are neurocutaneous diseases and syndromal developmental disorders, each with a characteristic phenotype. In some of these disorders, there is a genetic predisposition to the development of tumors. This article is intended as an overview of selected mosaic diseases. METHODS This review is based on publications retrieved by a selective search in PubMed, with particular attention to recent articles in high-ranking journals dealing with asymmetric growth disturbances, focal brain malformations, mosaic diseases due to dysregulation of the RAS/RAF signaling pathway (mosaic RASopathies), and vascular malformations. RESULTS The identification of postzygotic mutations has led to the reclassification of traditional disease entities and to a better understanding of their pathogenesis. Diagnosis is aided by modern next-generation sequencing (NGS) techniques that allow the detection even of low-grade mosaics. Many mosaic mutations are not detectable in blood, but only in the affected tissue, e.g., the skin. Genetic mosaic diseases often manifest themselves in the skin and brain, and by facial dysmorphism, asymmetrical growth disturbances, and vascular malformations. CONCLUSION The possibility of a mosaic disease should be kept in mind in the diag- nostic evaluation of patients with asymmetrical growth disturbances, focal neuronal migration disturbances, vascular malformations, and linear skin abnormalities. The demonstration of a postzygotic mutation often affords relief to the parents of an affected child, since this means that there is no increased risk for recurrence of the same disorder in future children. Correct classification is important, as molecular available for certain mosaic diseases, e.g., PIK3CA-related overgrowth spectrum (PROS) disorder.
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Affiliation(s)
- Ute Moog
- Institute of Human Genetics. University Hospital Heidelberg, Heidelberg
| | - Ute Felbor
- Institute of Human Genetics, University of Greifswald and Interfaculty Institute for Genetics and Functional Genomics, Greifswald University, Greifswald
| | - Cristina Has
- Department of Dermatology and Venereology, University Medical Center Freiburg, Albert-Ludwigs-Universität Freiburg, Freiburg
| | - Birgit Zirn
- genetikum, Genetische Beratung und Diagnostik, Stuttgart
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Jiangyi W, Gang G, Guohai S, Dingwei Y. Germline mutation of TSC1 or TSC2 gene in Chinese patients with bilateral renal angiomyolipomas and mutation spectrum of Chinese TSC patients. Aging (Albany NY) 2020; 12:756-766. [PMID: 31927531 PMCID: PMC6977674 DOI: 10.18632/aging.102654] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 12/24/2019] [Indexed: 12/28/2022]
Abstract
The germline mutation of the TSC1/2 gene in bilateral renal angiomyolipomas is unclear. Meanwhile, the mutation spectrum of Chinese TSC patients has not been revealed. We recruited 78 patients diagnosed with bilateral renal AMLs. High-throughput sequencing was used to detect any variants in TSC1/2 genes. The results showed that 28.6% of patients diagnosed before 45 were with positive results of TSC1/2 test. The rate decreased to 14.3% for those with onset age over 45. For the 315 previously reported Chinese patients, TSC1 patients were more likely to be affected by nonsense mutations (51.1% vs. 20.7%, p<0.001) and had a significantly higher rate of family history than TSC2 patients (37.8% vs. 19.6%, p=0.0067). Moreover, exon8, 15, and 18 were the hotspot mutation regions for TSC1, and exon 29, 33 and 40 were the most common mutation regions for TSC2. Besides, Chinese TSC patients carried more TSC2 alterations (85.7% vs.76.2%, p<0.001), and were more likely to have a family history than those from TOSCA (22.2% vs. 13.9%, p<0.001). In conclusion, patients affected by bilateral renal AMLs should receive genetic testing of TSC ½ genes and Chinese TSC patients have relatively hotspot mutation regions, which are helpful to genetic counseling and clinical decision making.
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Affiliation(s)
- Wang Jiangyi
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, PR China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, PR China
| | - Guo Gang
- Department of Urology, the State Key Laboratory of Kidney Diseases, Chinese PLA General Hospital, Beijing, PR China
| | - Shi Guohai
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, PR China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, PR China
| | - Ye Dingwei
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, PR China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, PR China
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Abstract
PURPOSE OF REVIEW There has been rapid progress in defining novel causative gene variants responsible for a large spectrum of human epilepsy syndromes and subtypes. Of particular interest is the discovery that somatic mutations, for example, noninherited mutations occurring in neuroglial progenitor cells during embryonic brain development, are highly linked to malformations of cortical development (MCD) such as focal cortical dysplasia (FCD) type II and hemimegalencephaly. RECENT FINDINGS Somatic gene variants have been identified in genes encoding regulatory proteins within the mechanistic target of rapamycin (mTOR) signaling cascade and have thus comprised the group classified as mTORopathies. FCD II and hemimegalencephaly often result from mutations in identical genes suggesting that these are spectrum disorders. An exciting recent development has been the identification of somatic mutations causing both FCD Ia and nonlesional neocortical epilepsy. SUMMARY Defining somatic gene mutations in brain tissue specimens has shed new light on how MCD form and the mechanisms of epileptogenesis associated with MCD. Trials of mTOR inhibitors in tuberous sclerosis complex have demonstrated that inhibition of mTOR activation in mTORopathies can reduce seizure frequency. New somatic mutations found for a variety of epilepsy syndromes may provide new targets for clinical therapeutics.
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He J, Zhou W, Shi J, Lin J, Zhang B, Sun Z. TSC1 and TSC2 Gene Mutations in Chinese Tuberous Sclerosis Complex Patients Clinically Characterized by Epilepsy. Genet Test Mol Biomarkers 2020; 24:1-5. [PMID: 31855466 DOI: 10.1089/gtmb.2019.0094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Jing He
- Department of Epilepsy Center, Tsinghua University Yuquan Hospital, Beijing, China
| | - Wenjing Zhou
- Department of Epilepsy Center, Tsinghua University Yuquan Hospital, Beijing, China
| | - Jie Shi
- Department of Epilepsy Center, Tsinghua University Yuquan Hospital, Beijing, China
| | - Jiuluan Lin
- Department of Epilepsy Center, Tsinghua University Yuquan Hospital, Beijing, China
| | - Bingqing Zhang
- Department of Epilepsy Center, Tsinghua University Yuquan Hospital, Beijing, China
| | - Zhaohui Sun
- Department of Epilepsy Center, Tsinghua University Yuquan Hospital, Beijing, China
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