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1.
JCI Insight ; 9(3)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38175707

RESUMO

Cutaneous neurofibromas (cNFs) are benign Schwann cell (SC) tumors arising from subepidermal glia. Individuals with neurofibromatosis type 1 (NF1) may develop thousands of cNFs, which greatly affect their quality of life. cNF growth is driven by the proliferation of NF1-/- SCs and their interaction with the NF1+/- microenvironment. We analyzed the crosstalk between human cNF-derived SCs and fibroblasts (FBs), identifying an expression signature specific to the SC-FB interaction. We validated the secretion of proteins involved in immune cell migration, suggesting a role of SC-FB crosstalk in immune cell recruitment. The signature also captured components of developmental signaling pathways, including the cAMP elevator G protein-coupled receptor 68 (GPR68). Activation of Gpr68 by ogerin in combination with the MEK inhibitor (MEKi) selumetinib reduced viability and induced differentiation and death of human cNF-derived primary SCs, a result corroborated using an induced pluripotent stem cell-derived 3D neurofibromasphere model. Similar results were obtained using other Gpr68 activators or cAMP analogs/adenylyl cyclase activators in combination with selumetinib. Interestingly, whereas primary SC cultures restarted their proliferation after treatment with selumetinib alone was stopped, the combination of ogerin-selumetinib elicited a permanent halt on SC expansion that persisted after drug removal. These results indicate that unbalancing the Ras and cAMP pathways by combining MEKi and cAMP elevators could be used as a potential treatment for cNFs.


Assuntos
Neurofibroma , Neurofibromatose 1 , Neoplasias Cutâneas , Triazinas , Humanos , Qualidade de Vida , Neurofibroma/tratamento farmacológico , Neurofibromatose 1/tratamento farmacológico , Neurofibromatose 1/patologia , Álcoois Benzílicos , Neoplasias Cutâneas/patologia , Inibidores de Proteínas Quinases/farmacologia , Microambiente Tumoral , Receptores Acoplados a Proteínas G
2.
Arch Toxicol ; 97(7): 1943-1961, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37195449

RESUMO

Hair cell (HC) loss by epithelial extrusion has been described to occur in the rodent vestibular system during chronic 3,3'-iminodipropionitrile (IDPN) ototoxicity. This is preceded by dismantlement of the calyceal junction in the contact between type I HC (HCI) and calyx afferent terminals. Here, we evaluated whether these phenomena have wider significance. First, we studied rats receiving seven different doses of streptomycin, ranging from 100 to 800 mg/kg/day, for 3-8 weeks. Streptomycin caused loss of vestibular function associated with partial loss of HCI and decreased expression of contactin-associated protein (CASPR1), denoting calyceal junction dismantlement, in the calyces encasing the surviving HCI. Additional molecular and ultrastructural data supported the conclusion that HC-calyx detachment precede HCI loss by extrusion. Animals allowed to survive after the treatment showed functional recuperation and rebuilding of the calyceal junction. Second, we evaluated human sensory epithelia obtained during therapeutic labyrinthectomies and trans-labyrinthine tumour excisions. Some samples showed abnormal CASPR1 label strongly suggestive of calyceal junction dismantlement. Therefore, reversible dismantlement of the vestibular calyceal junction may be a common response triggered by chronic stress, including ototoxic stress, before HCI loss. This may partly explain clinical observations of reversion in function loss after aminoglycoside exposure.


Assuntos
Células Ciliadas Vestibulares , Vestíbulo do Labirinto , Humanos , Ratos , Animais , Estreptomicina/toxicidade , Vestíbulo do Labirinto/patologia , Epitélio/patologia , Células Ciliadas Vestibulares/patologia , Células Ciliadas Auditivas/patologia
3.
iScience ; 26(2): 106096, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36818284

RESUMO

Malignant peripheral nerve sheath tumors (MPNSTs) are soft-tissue sarcomas of the peripheral nervous system that develop either sporadically or in the context of neurofibromatosis type 1 (NF1). MPNST diagnosis can be challenging and treatment outcomes are poor. We present here a resource consisting of the genomic characterization of 9 widely used human MPNST cell lines for their use in translational research. NF1-related cell lines recapitulated primary MPNST copy number profiles, exhibited NF1, CDKN2A, and SUZ12/EED tumor suppressor gene (TSG) inactivation, and presented no gain-of-function mutations. In contrast, sporadic cell lines collectively displayed different TSG inactivation patterns and presented kinase-activating mutations, fusion genes, altered mutational frequencies and COSMIC signatures, and different methylome-based classifications. Cell lines re-classified as melanomas and other sarcomas exhibited a different drug-treatment response. Deep genomic analysis, methylome-based classification, and cell-identity marker expression, challenged the identity of common MPNST cell lines, opening an opportunity to revise MPNST differential diagnosis.

4.
Pediatr Dermatol ; 40(1): 179-181, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36151877

RESUMO

Linear Cowden nevus, also known as linear PTEN nevus, is a type of epidermal nevus, first described in 2007, which is seen in patients with PTEN hamartoma tumor syndrome. It is considered to be a type 2 form of segmental mosaicism, and we suggest that it has certain clinical features that distinguish it from epidermal nevi seen in similar conditions, such as Proteus syndrome. We present a case of linear Cowden nevus in a 4-year-old boy and review the literature.


Assuntos
Síndrome do Hamartoma Múltiplo , Nevo Sebáceo de Jadassohn , Nevo , Masculino , Humanos , Pré-Escolar , Síndrome do Hamartoma Múltiplo/diagnóstico , Síndrome do Hamartoma Múltiplo/genética , Nevo Sebáceo de Jadassohn/diagnóstico , Nevo Sebáceo de Jadassohn/genética , Nevo/genética , Nevo/patologia , Mosaicismo , PTEN Fosfo-Hidrolase/genética
5.
Mol Ther Nucleic Acids ; 30: 493-505, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36420221

RESUMO

NF2-related schwannomatosis (NF2-related SWN) is an autosomal dominant condition caused by loss of function variants in the NF2 gene, which codes for the protein Merlin and is characterized by the development of multiple tumors of the nervous system. The clinical presentation of the disease is variable and related to the type of the inherited germline variant. Here, we tested if phosphorodiamidate morpholino oligomers (PMOs) could be used to correct the splice signaling caused by variants at ±13 within the intron-exon boundary region and showed that the PMOs designed for these variants do not constitute a therapeutic approach. Furthermore, we evaluated the use of PMOs to decrease the severity of the effects of NF2 truncating variants with the aim of generating milder hypomorphic isoforms in vitro through the induction of the in-frame deletion of the exon-carrying variant. We were able to specifically induce the skipping of exons 4, 8, and 11 maintaining the NF2 gene reading frame at cDNA level. Only the skipping of exon 11 produced a hypomorphic Merlin (Merlin-e11), which is able to partially rescue the observed phenotype in primary fibroblast cultures from NF2-related SWN patients, being encouraging for the treatment of patients harboring truncating variants located in exon 11.

6.
Cell Rep ; 38(7): 110385, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35172160

RESUMO

Plexiform neurofibromas (pNFs) are developmental tumors that appear in neurofibromatosis type 1 individuals, constituting a major source of morbidity and potentially transforming into a highly metastatic sarcoma (MPNST). pNFs arise after NF1 inactivation in a cell of the neural crest (NC)-Schwann cell (SC) lineage. Here, we develop an iPSC-based NC-SC in vitro differentiation system and construct a lineage expression roadmap for the analysis of different 2D and 3D NF models. The best model consists of generating heterotypic spheroids (neurofibromaspheres) composed of iPSC-derived differentiating NF1(-/-) SCs and NF1(+/-) pNF-derived fibroblasts (Fbs). Neurofibromaspheres form by maintaining highly proliferative NF1(-/-) cells committed to the NC-SC axis due to SC-SC and SC-Fb interactions, resulting in SC linage cells at different maturation points. Upon engraftment on the mouse sciatic nerve, neurofibromaspheres consistently generate human NF-like tumors. Analysis of expression roadmap genes in human pNF single-cell RNA-seq data uncovers the presence of SC subpopulations at distinct differentiation states.


Assuntos
Células-Tronco Pluripotentes Induzidas/patologia , Neurofibroma Plexiforme/patologia , Células de Schwann/patologia , Adolescente , Adulto , Animais , Biomarcadores/metabolismo , Diferenciação Celular , Criança , Feminino , Humanos , Masculino , Mesoderma/patologia , Camundongos , Pessoa de Meia-Idade , Modelos Biológicos , Crista Neural/patologia , Nervo Isquiático/patologia , Esferoides Celulares/patologia , Adulto Jovem
7.
J Med Genet ; 59(10): 1017-1023, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35121649

RESUMO

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder caused by pathogenic variants in NF1 Recently, NF1 testing has been included as a clinical criterion for NF1 diagnosis. Additionally, preconception genetic counselling in patients with NF1 focuses on a 50% risk of transmitting the familial variant as the risk of having a sporadic NF1 is considered the same as the general population. METHODS: 829 individuals, 583 NF1 sporadic cases and 246 patients with NF1 with documented family history, underwent genetic testing for NF1. Genotyping and segregation analysis of NF1 familial variants was determined by microsatellite analysis and NF1 sequencing. RESULTS: The mutational analysis of NF1 in 154 families with two or more affected cases studied showed the co-occurrence of two different NF1 germline pathogenic variants in four families. The estimated mutation rate in those families was 3.89×10-3, 20 times higher than the NF1 mutation rate (~2×10-4) (p=0.0008). Furthermore, the co-occurrence of two different NF1 germline pathogenic variants in these families was 1:39, 60 times the frequency of sporadic NF1 (1:2500) (p=0.003). In all cases, the de novo NF1 pathogenic variant was present in a descendant of an affected male. In two cases, variants were detected in the inherited paternal wild-type allele. CONCLUSIONS: Our results, together with previous cases reported, suggest that the offspring of male patients with NF1 could have an increased risk of experiencing de novo NF1 pathogenic variants. This observation, if confirmed in additional cohorts, could have relevant implications for NF1 genetic counselling, family planning and NF1 genetic testing.


Assuntos
Neurofibromatose 1 , Genes da Neurofibromatose 1 , Aconselhamento Genético , Testes Genéticos , Humanos , Masculino , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/epidemiologia , Neurofibromatose 1/genética , Neurofibromina 1/genética
8.
J Med Genet ; 59(7): 678-686, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34348961

RESUMO

BACKGROUND: Neurofibromatosis type 2 (NF2) is an autosomal dominant disorder characterised by the development of multiple schwannomas, especially on vestibular nerves, and meningiomas. The UK NF2 Genetic Severity Score (GSS) is useful to predict the progression of the disease from germline NF2 pathogenic variants, which allows the clinical follow-up and the genetic counselling offered to affected families to be optimised. METHODS: 52 Spanish patients were classified using the GSS, and patients' clinical severity was measured and compared between GSS groups. The GSS was reviewed with the addition of phenotype quantification, genetic variant classification and functional assays of Merlin and its downstream pathways. Principal component analysis and regression models were used to evaluate the differences between severity and the effect of NF2 germline variants. RESULTS: The GSS was validated in the Spanish NF2 cohort. However, for 25% of mosaic patients and patients harbouring variants associated with mild and moderate phenotypes, it did not perform as well for predicting clinical outcomes as it did for pathogenic variants associated with severe phenotypes. We studied the possibility of modifying the mutation classification in the GSS by adding the impact of pathogenic variants on the function of Merlin in 27 cases. This revision helped to reduce variability within NF2 mutation classes and moderately enhanced the correlation between patient phenotype and the different prognosis parameters analysed (R2=0.38 vs R2=0.32, p>0001). CONCLUSIONS: We validated the UK NF2 GSS in a Spanish NF2 cohort, despite the significant phenotypic variability identified within it. The revision of the GSS, named Functional Genetic Severity Score, could add value for the classification of mosaic patients and patients showing mild and moderate phenotypes once it has been validated in other cohorts.


Assuntos
Neurofibromatose 2 , Genes da Neurofibromatose 2 , Humanos , Mutação/genética , Neurofibromatose 2/genética , Neurofibromina 2/genética , Fenótipo , Reino Unido/epidemiologia
9.
Hum Mutat ; 43(1): 74-84, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34747535

RESUMO

Constitutional LZTR1 or SMARCB1 pathogenic variants (PVs) have been found in ∼86% of familial and ∼40% of sporadic schwannomatosis cases. Hence, we performed massively parallel sequencing of the entire LZTR1, SMARCB1, and NF2 genomic loci in 35 individuals with schwannomas negative for constitutional first-hit PVs in the LZTR1/SMARCB1/NF2 coding sequences; however, with 22q deletion and/or a different NF2 PV in each tumor, including six cases with only one tumor available. Furthermore, we verified whether any other LZTR1/SMARCB1/NF2 (likely) PVs could be found in 16 cases carrying a SMARCB1 constitutional variant in the 3'-untranslated region (3'-UTR) c.*17C>T, c.*70C>T, or c.*82C>T. As no additional variants were found, functional studies were performed to clarify the effect of these 3'-UTR variants on the transcript. The 3'-UTR variants c.*17C>T and c.*82C>T showed pathogenicity by negatively affecting the SMARCB1 transcript level. Two novel deep intronic SMARCB1 variants, c.500+883T>G and c.500+887G>A, resulting in out-of-frame missplicing of intron 4, were identified in two unrelated individuals. Further resequencing of the entire repeat-masked genomics sequences of chromosome 22q in individuals negative for PVs in the SMARCB1/LZTR1/NF2 coding- and noncoding regions revealed five potential schwannomatosis-predisposing candidate genes, that is, MYO18B, NEFH, SGSM1, SGSM3, and SBF1, pending further verification.


Assuntos
Neurilemoma , Neurofibromatoses , Cromossomos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neurilemoma/genética , Neurilemoma/patologia , Neurofibromatoses/genética , Proteína SMARCB1/genética , Fatores de Transcrição/genética
10.
Bioinformatics ; 37(22): 4227-4229, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-33983414

RESUMO

SUMMARY: Germline copy-number variants (CNVs) are relevant mutations for multiple genetics fields, such as the study of hereditary diseases. However, available benchmarks show that all next-generation sequencing (NGS) CNV calling tools produce false positives. We developed CNVfilteR, an R package that uses the single-nucleotide variant calls usually obtained in germline NGS pipelines to identify those false positives. The package can detect both false deletions and false duplications. We evaluated CNVfilteR performance on callsets generated by 13 CNV calling tools on three whole-genome sequencing and 541 panel samples, showing a decrease of up to 44.8% in false positives and consistent F1-score increase. Using CNVfilteR to detect false-positive calls can improve the overall performance of existing CNV calling pipelines. AVAILABILITY AND IMPLEMENTATION: CNVfilteR is released under Artistic-2.0 License. Source code and documentation are freely available at Bioconductor (http://www.bioconductor.org/packages/CNVfilteR). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Software , Sequenciamento Completo do Genoma , Mutação , Variações do Número de Cópias de DNA
11.
Ophthalmic Genet ; 42(4): 474-479, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33886416

RESUMO

PURPOSE: To describe the clinical characteristics, the imaging findings, and the genetic results of a patient with cone-rod dystrophy (CORD) related to mutations in CEP290. METHODS: A case report of atypical CEP290-related CORD. Ophthalmological examination was performed, including best-corrected visual acuity (BCVA), fundus photography, fundus autofluorescence (FAF) imaging, optical coherence tomography (OCT), a visual field test, and electroretinography testing. The genetic test was performed by next-generation sequencing (NGS)-based panel test containing 336 genes. RESULTS: A 57-year-old female who had reported a visual loss for 5 years. BCVA was 20/100 in both eyes. The fundus examination revealed a hypopigmented halo around the fovea, showing a paracentral hyperautofluorescent ring on FAF. OCT demonstrated the presence of atrophy in the outer retinal layers. The genetic test identified the probably pathogenic variants c.4028delA and c.5254C>T in compound heterozygosis in CEP290. CONCLUSIONS: This is the first report to present the clinical characteristics, imaging findings, and genetic test results of a patient with CEP290-related CORD. Our case contributes to expanding the clinical involvement of CEP290 pathogenic variants. This study indicates that CEP290-related CORD may have a mild phenotype with late-onset dystrophy, making these patients interesting candidates for innovative treatments such as genetic therapeutic approaches.


Assuntos
Antígenos de Neoplasias/genética , Proteínas de Ciclo Celular/genética , Distrofias de Cones e Bastonetes/genética , Proteínas do Citoesqueleto/genética , Mutação , Distrofias de Cones e Bastonetes/diagnóstico por imagem , Distrofias de Cones e Bastonetes/fisiopatologia , Eletrorretinografia , Feminino , Testes Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Pessoa de Meia-Idade , Retina/fisiopatologia , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia , Testes de Campo Visual , Campos Visuais/fisiologia
12.
Sci Rep ; 11(1): 3661, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33574490

RESUMO

Neurofibromatosis Type 1 (NF1) is a genetic condition affecting approximately 1:3500 persons worldwide. The NF1 gene codes for neurofibromin protein, a GTPase activating protein (GAP) and a negative regulator of RAS. The NF1 gene undergoes alternative splicing of exon 23a (E23a) that codes for 21 amino acids placed at the center of the GAP related domain (GRD). E23a-containing type II neurofibromin exhibits a weaker Ras-GAP activity compared to E23a-less type I isoform. Exon E23a has been related with the cognitive impairment present in NF1 individuals. We designed antisense Phosphorodiamidate Morpholino Oligomers (PMOs) to modulate E23a alternative splicing at physiological conditions of gene expression and tested their impact during PC12 cell line neuronal differentiation. Results show that any dynamic modification of the natural ratio between type I and type II isoforms disturbed neuronal differentiation, altering the proper formation of neurites and deregulating both the MAPK/ERK and cAMP/PKA signaling pathways. Our results suggest an opposite regulation of these pathways by neurofibromin and the possible existence of a feedback loop sensing neurofibromin-related signaling. The present work illustrates the utility of PMOs to study alternative splicing that could be applied to other alternatively spliced genes in vitro and in vivo.


Assuntos
Processamento Alternativo/efeitos dos fármacos , Neurofibromatose 1/genética , Neurofibromina 1/genética , Oligonucleotídeos Antissenso/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Modelos Animais de Doenças , Éxons/genética , Proteínas Ativadoras de GTPase/genética , Humanos , Neurofibromatose 1/patologia , Neurofibromatose 1/terapia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Oligonucleotídeos Antissenso/genética , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteínas ras/genética
13.
Eur J Hum Genet ; 28(12): 1645-1655, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32561899

RESUMO

Although germline copy-number variants (CNVs) are the genetic cause of multiple hereditary diseases, detecting them from targeted next-generation sequencing data (NGS) remains a challenge. Existing tools perform well for large CNVs but struggle with single and multi-exon alterations. The aim of this work is to evaluate CNV calling tools working on gene panel NGS data and their suitability as a screening step before orthogonal confirmation in genetic diagnostics strategies. Five tools (DECoN, CoNVaDING, panelcn.MOPS, ExomeDepth, and CODEX2) were tested against four genetic diagnostics datasets (two in-house and two external) for a total of 495 samples with 231 single and multi-exon validated CNVs. The evaluation was performed using the default and sensitivity-optimized parameters. Results showed that most tools were highly sensitive and specific, but the performance was dataset dependant. When evaluating them in our diagnostics scenario, DECoN and panelcn.MOPS detected all CNVs with the exception of one mosaic CNV missed by DECoN. However, DECoN outperformed panelcn.MOPS specificity achieving values greater than 0.90 when using the optimized parameters. In our in-house datasets, DECoN and panelcn.MOPS showed the highest performance for CNV screening before orthogonal confirmation. Benchmarking and optimization code is freely available at https://github.com/TranslationalBioinformaticsIGTP/CNVbenchmarkeR .


Assuntos
Variações do Número de Cópias de DNA , Testes Genéticos/normas , Sequenciamento de Nucleotídeos em Larga Escala/normas , Análise de Sequência de DNA/normas , Alelos , Benchmarking , Testes Genéticos/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mosaicismo , Sensibilidade e Especificidade , Análise de Sequência de DNA/métodos
14.
Clin Genet ; 97(2): 264-275, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31573083

RESUMO

Children with neurofibromatosis type 1 (NF1) may exhibit an incomplete clinical presentation, making difficult to reach a clinical diagnosis. A phenotypic overlap may exist in children with other RASopathies or with other genetic conditions if only multiple café-au-lait macules (CALMs) are present. The syndromes that can converge in these inconclusive phenotypes have different clinical courses. In this context, an early genetic testing has been proposed to be clinically useful to manage these patients. We present the validation and implementation into diagnostics of a custom NGS panel (I2HCP, ICO-IMPPC Hereditary Cancer Panel) for testing patients with a clinical suspicion of a RASopathy (n = 48) and children presenting multiple CALMs (n = 102). We describe the mutational spectrum and the detection rates identified in these two groups of individuals. We identified pathogenic variants in 21 out of 48 patients with clinical suspicion of RASopathy, with mutations in NF1 accounting for 10% of cases. Furthermore, we identified pathogenic mutations mainly in the NF1 gene, but also in SPRED1, in more than 50% of children with multiple CALMs, exhibiting an NF1 mutational spectrum different from a group of clinically diagnosed NF1 patients (n = 80). An NGS panel strategy for the genetic testing of these two phenotype-defined groups outperforms previous strategies.


Assuntos
Manchas Café com Leite/genética , Diagnóstico Precoce , Testes Genéticos , Neurofibromatose 1/genética , Manchas Café com Leite/diagnóstico , Manchas Café com Leite/patologia , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Masculino , Mutação/genética , Proteínas de Neoplasias/genética , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/patologia , Neurofibromina 1/genética , Fenótipo
16.
Stem Cell Reports ; 12(2): 411-426, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30713041

RESUMO

Neurofibromatosis type 1 (NF1) is a tumor predisposition genetic disease caused by mutations in the NF1 tumor suppressor gene. Plexiform neurofibromas (PNFs) are benign Schwann cell (SC) tumors of the peripheral nerve sheath that develop through NF1 inactivation and can progress toward a malignant soft tissue sarcoma. There is a lack of non-perishable model systems to investigate PNF development. We reprogrammed PNF-derived NF1(-/-) cells, descendants from the tumor originating cell. These NF1(-/-)-induced pluripotent stem cells (iPSCs) captured the genomic status of PNFs and were able to differentiate toward neural crest stem cells and further to SCs. iPSC-derived NF1(-/-) SCs exhibited a continuous high proliferation rate, poor myelination ability, and a tendency to form 3D spheres that expressed the same markers as their PNF-derived primary SC counterparts. They represent a valuable model to study and treat PNFs. PNF-derived iPSC lines were banked for making them available.


Assuntos
Carcinogênese/genética , Reprogramação Celular/genética , Predisposição Genética para Doença/genética , Neurofibroma Plexiforme/genética , Neurofibromatose 1/genética , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Proliferação de Células/genética , Criança , Feminino , Genes Supressores de Tumor/fisiologia , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Crista Neural/fisiologia , Neurofibroma Plexiforme/sangue , Neurofibromatose 1/sangue , Células de Schwann/fisiologia , Adulto Jovem
17.
Hum Mutat ; 39(8): 1112-1125, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29774626

RESUMO

Plexiform neurofibromas (PNFs) are benign peripheral nerve sheath tumors involving large nerves present in 30%-50% Neurofibromatosis type 1 (NF1) patients. Atypical neurofibromas (ANF) are distinct nodular lesions with atypical features on histology that arise from PNFs. The risk and timeline of malignant transformation in ANF is difficult to assess. A recent NIH workshop has stratified ANFs and separated a subgroup with multiple atypical features and higher risk of malignant transformation termed atypical neurofibromatous neoplasms with uncertain biological potential (ANNUBP). We performed an analysis of intratumor heterogeneity on eight PNFs to link histological and genomic findings. Tumors were homogeneous although histological and molecular heterogeneity was identified. All tumors were 2n, almost mutation-free and had a clonal NF1(-/-) origin. Two ANFs from the same patient showed atypical features on histology and deletions of CDKN2A/B. One of the ANFs exhibited different areas in which the degree of histological atypia correlated with the heterozygous or homozygous loss of the CDKN2A/B loci. CDKN2A/B deletions in different areas originated independently. Results may indicate that loss of a single CDKN2A/B copy in NF1(-/-) cells is sufficient to start ANF development and that total inactivation of both copies of CDKN2A/B is necessary to form an ANNUBP.


Assuntos
Neurofibroma Plexiforme/genética , Neurofibroma/genética , Neurofibromatose 1/genética , Adulto , Idoso , Criança , Pré-Escolar , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Genômica/métodos , Humanos , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética
18.
JAMA Dermatol ; 154(3): 341-346, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29322178

RESUMO

Importance: Neurofibromatosis type 2 (NF2) is a devastating genetic condition characterized by the development of multiple tumors of the nervous system. An early diagnosis of individuals with NF2 would facilitate treatment and reduction of disease impact because most severe effects of the disease do not usually develop before adolescence. Little attention has traditionally been paid to dermatological signs in NF2. However, skin plaques are commonly seen in patients with NF2, normally appearing either at birth or early childhood, providing an opportunity for early NF2 detection and testing. Objective: To determine the clinical utility of skin plaque identification and characterization in children for reaching an early diagnosis of patients with NF2 and to evaluate their molecular pathogenesis and their use in the genetic diagnostics of NF2. Design, Setting, and Participants: Diagnostic test study by the histological and genetic characterization of skin plaques from patients with NF2. Patients were 7 individuals with NF2 or clinical suspicion of NF2 treated at the Spanish Reference Center on Phakomatoses. Main Outcomes and Measures: Histological evaluation of all skin plaques was performed. Fresh skin plaques were cultured to obtain Schwann cells and the NF2 gene was genetically analyzed. For all 7 patients, NF2 clinical history was reviewed. Results: In all 7 patients (4 male and 3 female), all skin plaques analyzed were histologically characterized as plexiform schwannomas. Genetic analysis of primary Schwann cell cultures derived from them allowed the identification of a constitutional and a somatic NF2 mutation. Genetic testing allowed the early diagnosis of NF2 in a child only exhibiting the presence of skin plaques. Most of the patients with NF2 analyzed had an early presentation of skin plaques and a severe NF2 phenotype. Conclusions and Relevance: This work emphasizes the clinical utility of a careful dermatological inspection and the correct identification of skin plaques in children for an early diagnosis of NF2. We show for the first time that Schwann cells derived from skin plaque plexiform schwannomas bear the double inactivation of the NF2 gene and thus constitute an excellent source of tissue for genetic testing, especially in the context of mosaicism.


Assuntos
Genes da Neurofibromatose 2 , Neurilemoma/genética , Neurofibromatose 2/diagnóstico , Neurofibromatose 2/genética , Neoplasias Cutâneas/genética , Adolescente , Adulto , Pré-Escolar , Feminino , Testes Genéticos , Humanos , Masculino , Mutação , Neurilemoma/patologia , Células de Schwann , Neoplasias Cutâneas/patologia
19.
Sci Rep ; 7: 37984, 2017 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-28050010

RESUMO

Next generation sequencing panels have been developed for hereditary cancer, although there is some debate about their cost-effectiveness compared to exome sequencing. The performance of two panels is compared to exome sequencing. Twenty-four patients were selected: ten with identified mutations (control set) and fourteen suspicious of hereditary cancer but with no mutation (discovery set). TruSight Cancer (94 genes) and a custom panel (122 genes) were assessed alongside exome sequencing. Eighty-three genes were targeted by the two panels and exome sequencing. More than 99% of bases had a read depth of over 30x in the panels, whereas exome sequencing covered 94%. Variant calling with standard settings identified the 10 mutations in the control set, with the exception of MSH6 c.255dupC using TruSight Cancer. In the discovery set, 240 unique non-silent coding and canonic splice-site variants were identified in the panel genes, 7 of them putatively pathogenic (in ATM, BARD1, CHEK2, ERCC3, FANCL, FANCM, MSH2). The three approaches identified a similar number of variants in the shared genes. Exomes were more expensive than panels but provided additional data. In terms of cost and depth, panels are a suitable option for genetic diagnostics, although exomes also identify variants in non-targeted genes.


Assuntos
Predisposição Genética para Doença , Testes Genéticos/métodos , Síndromes Neoplásicas Hereditárias/diagnóstico , Benchmarking , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Síndromes Neoplásicas Hereditárias/genética , Sequenciamento do Exoma/métodos
20.
Sci Rep ; 7: 39348, 2017 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-28051113

RESUMO

We wanted to implement an NGS strategy to globally analyze hereditary cancer with diagnostic quality while retaining the same degree of understanding and control we had in pre-NGS strategies. To do this, we developed the I2HCP panel, a custom bait library covering 122 hereditary cancer genes. We improved bait design, tested different NGS platforms and created a clinically driven custom data analysis pipeline. The I2HCP panel was developed using a training set of hereditary colorectal cancer, hereditary breast and ovarian cancer and neurofibromatosis patients and reached an accuracy, analytical sensitivity and specificity greater than 99%, which was maintained in a validation set. I2HCP changed our diagnostic approach, involving clinicians and a genetic diagnostics team from panel design to reporting. The new strategy improved diagnostic sensitivity, solved uncertain clinical diagnoses and identified mutations in new genes. We assessed the genetic variation in the complete set of hereditary cancer genes, revealing a complex variation landscape that coexists with the disease-causing mutation. We developed, validated and implemented a custom NGS-based strategy for hereditary cancer diagnostics that improved our previous workflows. Additionally, the existence of a rich genetic variation in hereditary cancer genes favors the use of this panel to investigate their role in cancer risk.


Assuntos
Detecção Precoce de Câncer/métodos , Testes Genéticos/métodos , Técnicas de Diagnóstico Molecular/métodos , Síndromes Neoplásicas Hereditárias/diagnóstico , Síndromes Neoplásicas Hereditárias/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Sensibilidade e Especificidade
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