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1.
Am J Hum Genet ; 109(10): 1828-1849, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36084634

RESUMO

Orofaciodigital syndrome (OFD) is a genetically heterogeneous ciliopathy characterized by anomalies of the oral cavity, face, and digits. We describe individuals with OFD from three unrelated families having bi-allelic loss-of-function variants in SCNM1 as the cause of their condition. SCNM1 encodes a protein recently shown to be a component of the human minor spliceosome. However, so far the effect of loss of SCNM1 function on human cells had not been assessed. Using a comparative transcriptome analysis between fibroblasts derived from an OFD-affected individual harboring SCNM1 mutations and control fibroblasts, we identified a set of genes with defective minor intron (U12) processing in the fibroblasts of the affected subject. These results were reproduced in SCNM1 knockout hTERT RPE-1 (RPE-1) cells engineered by CRISPR-Cas9-mediated editing and in SCNM1 siRNA-treated RPE-1 cultures. Notably, expression of TMEM107 and FAM92A encoding primary cilia and basal body proteins, respectively, and that of DERL2, ZC3H8, and C17orf75, were severely reduced in SCNM1-deficient cells. Primary fibroblasts containing SCNM1 mutations, as well as SCNM1 knockout and SCNM1 knockdown RPE-1 cells, were also found with abnormally elongated cilia. Conversely, cilia length and expression of SCNM1-regulated genes were restored in SCNM1-deficient fibroblasts following reintroduction of SCNM1 via retroviral delivery. Additionally, functional analysis in SCNM1-retrotransduced fibroblasts showed that SCNM1 is a positive mediator of Hedgehog (Hh) signaling. Our findings demonstrate that defective U12 intron splicing can lead to a typical ciliopathy such as OFD and reveal that primary cilia length and Hh signaling are regulated by the minor spliceosome through SCNM1 activity.


Assuntos
Ciliopatias , Síndromes Orofaciodigitais , Cílios/genética , Cílios/metabolismo , Ciliopatias/genética , Proteínas Hedgehog/metabolismo , Humanos , Íntrons/genética , Mutação/genética , Síndromes Orofaciodigitais/genética , Splicing de RNA/genética , Fatores de Processamento de RNA/metabolismo , RNA Interferente Pequeno/metabolismo , Spliceossomos/genética , Spliceossomos/metabolismo
2.
Am J Hum Genet ; 108(11): 2112-2129, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34626534

RESUMO

Upregulated signal flow through RAS and the mitogen-associated protein kinase (MAPK) cascade is the unifying mechanistic theme of the RASopathies, a family of disorders affecting development and growth. Pathogenic variants in more than 20 genes have been causally linked to RASopathies, the majority having a dominant role in promoting enhanced signaling. Here, we report that SPRED2 loss of function is causally linked to a recessive phenotype evocative of Noonan syndrome. Homozygosity for three different variants-c.187C>T (p.Arg63∗), c.299T>C (p.Leu100Pro), and c.1142_1143delTT (p.Leu381Hisfs∗95)-were identified in four subjects from three families. All variants severely affected protein stability, causing accelerated degradation, and variably perturbed SPRED2 functional behavior. When overexpressed in cells, all variants were unable to negatively modulate EGF-promoted RAF1, MEK, and ERK phosphorylation, and time-course experiments in primary fibroblasts (p.Leu100Pro and p.Leu381Hisfs∗95) documented an increased and prolonged activation of the MAPK cascade in response to EGF stimulation. Morpholino-mediated knockdown of spred2a and spred2b in zebrafish induced defects in convergence and extension cell movements indicating upregulated RAS-MAPK signaling, which were rescued by expressing wild-type SPRED2 but not the SPRED2Leu381Hisfs∗95 protein. The clinical phenotype of the four affected individuals included developmental delay, intellectual disability, cardiac defects, short stature, skeletal anomalies, and a typical facial gestalt as major features, without the occurrence of the distinctive skin signs characterizing Legius syndrome. These features, in part, characterize the phenotype of Spred2-/- mice. Our findings identify the second recessive form of Noonan syndrome and document pleiotropic consequences of SPRED2 loss of function in development.


Assuntos
Mutação com Perda de Função , Síndrome de Noonan/genética , Fenótipo , Proteínas Repressoras/genética , Alelos , Animais , Células COS , Chlorocebus aethiops , Células HEK293 , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Knockout , Peixe-Zebra
3.
World J Surg ; 48(4): 801-806, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38375927

RESUMO

BACKGROUND: The majority of inguinal hernias are usually paucisymptomatic, so are restored electively. The main purpose of this study is to assess the trends in hernia repair surgery before and during the pandemic period, analyzing an Italian hospital series of 390 patients, in an attempt to quantify the negative impact regarding social costs derived from the Covid-19 outbreak. Moreover, we want to focus on the concept of apparently minor pathology as hernioplasty which could represent a life-threatening condition for patients. METHODS: The study population consisted of all patients operated for inguinal hernia in a General Surgery Unit from 2019 to 2021, divided into a pre-pandemic and a pandemic period. RESULTS: The Covid-19 pandemic increased urgent operations in a complicated setting. A statistically significant difference was found regarding the trend of hospitalization length as well as a strong positive correlation between the severity of hernia and the hospitalization length. CONCLUSIONS: During the pandemic, it has been registered a mishandling of inguinal hernias to the detriment of both the healthcare system and patients, due to multifactorial issues and, in particular, to the restrictions imposed by the regional government that erroneously declassed hernia pathology as a minor problem for public health. We do believe that patients, after diagnosis of inguinal hernia, should learn the Taxis maneuver for its feasibility and ease of execution, in order to reduce access to emergencies in many cases and likewise to better pain and discomfort perceived, even in the event of unexpected worldwide healthcare scenario.


Assuntos
COVID-19 , Hérnia Inguinal , Humanos , Hérnia Inguinal/cirurgia , Pandemias/prevenção & controle , Herniorrafia/métodos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Hospitais , Itália/epidemiologia , Telas Cirúrgicas
4.
Am J Hum Genet ; 107(5): 977-988, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33058759

RESUMO

PRKACA and PRKACB code for two catalytic subunits (Cα and Cß) of cAMP-dependent protein kinase (PKA), a pleiotropic holoenzyme that regulates numerous fundamental biological processes such as metabolism, development, memory, and immune response. We report seven unrelated individuals presenting with a multiple congenital malformation syndrome in whom we identified heterozygous germline or mosaic missense variants in PRKACA or PRKACB. Three affected individuals were found with the same PRKACA variant, and the other four had different PRKACB mutations. In most cases, the mutations arose de novo, and two individuals had offspring with the same condition. Nearly all affected individuals and their affected offspring shared an atrioventricular septal defect or a common atrium along with postaxial polydactyly. Additional features included skeletal abnormalities and ectodermal defects of variable severity in five individuals, cognitive deficit in two individuals, and various unusual tumors in one individual. We investigated the structural and functional consequences of the variants identified in PRKACA and PRKACB through the use of several computational and experimental approaches, and we found that they lead to PKA holoenzymes which are more sensitive to activation by cAMP than are the wild-type proteins. Furthermore, expression of PRKACA or PRKACB variants detected in the affected individuals inhibited hedgehog signaling in NIH 3T3 fibroblasts, thereby providing an underlying mechanism for the developmental defects observed in these cases. Our findings highlight the importance of both Cα and Cß subunits of PKA during human development.


Assuntos
Anormalidades Múltiplas/genética , Disfunção Cognitiva/genética , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/genética , Dedos/anormalidades , Mutação em Linhagem Germinativa , Defeitos dos Septos Cardíacos/genética , Polidactilia/genética , Dedos do Pé/anormalidades , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/patologia , Adolescente , Adulto , Animais , Sequência de Bases , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/patologia , AMP Cíclico/metabolismo , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/química , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/deficiência , Feminino , Dedos/patologia , Regulação da Expressão Gênica no Desenvolvimento , Defeitos dos Septos Cardíacos/diagnóstico , Defeitos dos Septos Cardíacos/patologia , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Holoenzimas/química , Holoenzimas/deficiência , Holoenzimas/genética , Humanos , Recém-Nascido , Masculino , Camundongos , Modelos Moleculares , Mosaicismo , Células NIH 3T3 , Linhagem , Polidactilia/diagnóstico , Polidactilia/patologia , Estrutura Secundária de Proteína , Dedos do Pé/patologia
5.
Am J Hum Genet ; 107(3): 499-513, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32721402

RESUMO

Signal transduction through the RAF-MEK-ERK pathway, the first described mitogen-associated protein kinase (MAPK) cascade, mediates multiple cellular processes and participates in early and late developmental programs. Aberrant signaling through this cascade contributes to oncogenesis and underlies the RASopathies, a family of cancer-prone disorders. Here, we report that de novo missense variants in MAPK1, encoding the mitogen-activated protein kinase 1 (i.e., extracellular signal-regulated protein kinase 2, ERK2), cause a neurodevelopmental disease within the RASopathy phenotypic spectrum, reminiscent of Noonan syndrome in some subjects. Pathogenic variants promote increased phosphorylation of the kinase, which enhances translocation to the nucleus and boosts MAPK signaling in vitro and in vivo. Two variant classes are identified, one of which directly disrupts binding to MKP3, a dual-specificity protein phosphatase negatively regulating ERK function. Importantly, signal dysregulation driven by pathogenic MAPK1 variants is stimulus reliant and retains dependence on MEK activity. Our data support a model in which the identified pathogenic variants operate with counteracting effects on MAPK1 function by differentially impacting the ability of the kinase to interact with regulators and substrates, which likely explains the minor role of these variants as driver events contributing to oncogenesis. After nearly 20 years from the discovery of the first gene implicated in Noonan syndrome, PTPN11, the last tier of the MAPK cascade joins the group of genes mutated in RASopathies.


Assuntos
Carcinogênese/genética , Proteína Quinase 1 Ativada por Mitógeno/genética , Transtornos do Neurodesenvolvimento/genética , Síndrome de Noonan/genética , Pré-Escolar , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/genética , Masculino , Mutação de Sentido Incorreto/genética , Transtornos do Neurodesenvolvimento/patologia , Síndrome de Noonan/fisiopatologia , Fenótipo , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Transdução de Sinais , Sequenciamento do Exoma , Proteínas ras/genética
6.
Clin Genet ; 104(1): 136-138, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36757675

RESUMO

Noonan syndrome (NS) belongs to RASopathies, a family of disorders caused by unregulated signaling through the RAS-MAPK pathway. Herein, we report on an individual with molecularly confirmed diagnosis of NS showing asymptomatic enlarged spinal nerve roots, which are distinctive features of neurofibromatosis type 1. To date, a total of 16 patients with neurogenic tumors resembling neurofibromas/schwannomas and a molecularly confirmed diagnosis of a non-NF1 RASopathy have been reported, adding this further feature shared among RASopathies.


Assuntos
Neurofibromatoses , Neurofibromatose 1 , Síndrome de Noonan , Humanos , Síndrome de Noonan/diagnóstico , Síndrome de Noonan/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Neurofibromatose 1/complicações , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/genética , Raízes Nervosas Espinhais/diagnóstico por imagem , Mutação
7.
Am J Med Genet A ; 191(4): 1101-1106, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36598152

RESUMO

Mosaic genome-wide paternal uniparental disomy (GWpUPD) is a rare condition in which two euploid cell lines coexist in the same individual, one with biparental content and one with genome-wide paternal isodisomy. We report a complex prenatal diagnosis with discordant results from cultured and uncultured samples. A pregnant woman was referred for placental mesenchymal dysplasia and fetal omphalocele. Karyotype, array-CGH and Beckwith-Wiedemann Syndrome (BWS) testing (methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) of 11p15) performed on amniocytes were negative. After intrauterine fetal demise, the clinical suspicion persisted and BWS MS-MLPA was repeated on cultured cells from umbilical cord and amniotic fluid, revealing a mosaicism for KvH19 hypermethylation/KCNQ1OT1:TSS:DMR hypomethylation. These results, along with microsatellite analysis of the BWS region, were consistent with mosaic paternal 11p15 isodisomy. A concurrent maternal contamination exclusion test, analyzing polymorphic microsatellite markers on multiple chromosomes, showed an imbalance in favor of paternal alleles at all examined loci on cultured amniocytes and umbilical cord samples. This led to suspicion of mosaic GWpUPD, later confirmed by SNP-array, identifying a mosaic genome-wide paternal isodisomy affecting 60% of fetal cells. The assessment of mosaic GWpUPD requires multiple approaches beyond the current established diagnostic processes, also entertaining possible low-rate mosaicism. Clinical acumen and an integrated testing approach are the key to a successful diagnosis.


Assuntos
Síndrome de Beckwith-Wiedemann , Dissomia Uniparental , Humanos , Feminino , Gravidez , Placenta , Mosaicismo , Metilação de DNA , Síndrome de Beckwith-Wiedemann/genética , Células Cultivadas
8.
Arch Orthop Trauma Surg ; 143(6): 3091-3101, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35788762

RESUMO

AIM: Aim of the study was to assess whether early surgery and other clinical and orthogeriatric parameters could affect mortality rate in hip fracture patients aged > 85. MATERIALS AND METHODS: Data regarding a 42-month period were retrospectively obtained from the institutional medical records and registry data. Gender, age, fracture pattern, surgical technique, type of anesthesia, timing of surgical intervention (within 24, 48 or 72 h from admission), days of hospitalization, mortality rate divided in intra-hospital, at 30 days and at 1 year were collected for the whole population. Some additional data were collected for an orthogeriatric subgroup. RESULTS: 941 patients were considered, with a mean age of 89 years. Surgery was performed within 24, 48 and 72 h in 24.4%, 54.5% and 66.1% of cases, respectively. Intra-hospital mortality rate resulted to be 3.4%, while mortality at 30 days and 1 year resulted to be 4.5% and 31%, respectively. Early surgery within 48 and 72 h were significantly associated with a lower intra-hospital and 30-day mortality rate. In the orthogeriatric subgroup (394 patients), a significant association with a higher mortality rate was found for general anesthesia, number of comorbidities, ADL (Activities of Daily Living) < 3, transfer to other departments. CONCLUSIONS: In over-85 hip fracture patients, the threshold for early surgery might be moved to 72 h to allow patients pre-operative stabilization and medical optimization as intra-hospital and 30-day mortality rates remain significantly lower. Advanced age, male sex, number of comorbidities, pre-operative dependency in ADL, general anesthesia, length of hospitalization and transfer to other departments were significantly related to mortality rate.


Assuntos
Atividades Cotidianas , Fraturas do Quadril , Humanos , Masculino , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Fraturas do Quadril/epidemiologia , Hospitalização , Comorbidade
9.
Medicina (Kaunas) ; 59(10)2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37893421

RESUMO

Background and Objectives: The use of oncoplastic techniques has spread widely in the last decade, with an expansion of the indications and demonstration of excellent oncological safety profiles. A potential downside may be the increased complication rates, which could influence the timing of adjuvant therapy. To date, there is increasing evidence that negative pressure therapy on closed wounds can reduce complication rates after surgery. From this perspective, we tested the use of portable negative pressure wound dressings (NPWDs) in oncoplastic surgery to minimize early post-operative admissions to the outpatient clinic and prevent surgical complications. Materials and Methods: An observational prospective cohort study was conducted on a population of patients who underwent quadrantectomy and wise-pattern reduction mammoplasty for breast cancer. The primary objective of the study is represented by the evaluation of the impact of NPWD on post-operative outcomes in an oncoplastic surgery setting. Patients enrolled between January 2021 and January 2023 were divided into two groups, the conventional dressing (CD) group and the NPWD group, by a simple randomization list. Results: A total of 100 patients were enrolled, with 52 in the CD group and 48 in the NPWD group. The use of NPWD significantly reduced the wound dehiscence rate (2.0% vs. 7.7% p = 0.002) and the number of one-month postoperative admissions to our clinic (3.8 ± 1.1 vs. 5.7 ± 1.3 p = 0.0009). Although not significant, it is possible to note a trend of reduction of clinically relevant postoperative total complications in patients treated with NPWDs. Conclusions: NPWDs may represent a useful tool in the post-surgical management of complex oncoplastic procedures, ensuring less wound dehiscence. Furthermore, the use of these dressings led to a significant reduction in admissions to the clinic, promoting a lower use of resources by hospitals and effective prevention of possible complications.


Assuntos
Neoplasias da Mama , Mamoplastia , Humanos , Feminino , Neoplasias da Mama/complicações , Estudos Prospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Mamoplastia/efeitos adversos , Mamoplastia/métodos , Bandagens
10.
Am J Hum Genet ; 105(3): 640-657, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31402090

RESUMO

The identification of genetic variants implicated in human developmental disorders has been revolutionized by second-generation sequencing combined with international pooling of cases. Here, we describe seven individuals who have diverse yet overlapping developmental anomalies, and who all have de novo missense FBXW11 variants identified by whole exome or whole genome sequencing and not reported in the gnomAD database. Their phenotypes include striking neurodevelopmental, digital, jaw, and eye anomalies, and in one individual, features resembling Noonan syndrome, a condition caused by dysregulated RAS signaling. FBXW11 encodes an F-box protein, part of the Skp1-cullin-F-box (SCF) ubiquitin ligase complex, involved in ubiquitination and proteasomal degradation and thus fundamental to many protein regulatory processes. FBXW11 targets include ß-catenin and GLI transcription factors, key mediators of Wnt and Hh signaling, respectively, critical to digital, neurological, and eye development. Structural analyses indicate affected residues cluster at the surface of the loops of the substrate-binding domain of FBXW11, and the variants are predicted to destabilize the protein and/or its interactions. In situ hybridization studies on human and zebrafish embryonic tissues demonstrate FBXW11 is expressed in the developing eye, brain, mandibular processes, and limb buds or pectoral fins. Knockdown of the zebrafish FBXW11 orthologs fbxw11a and fbxw11b resulted in embryos with smaller, misshapen, and underdeveloped eyes and abnormal jaw and pectoral fin development. Our findings support the role of FBXW11 in multiple developmental processes, including those involving the brain, eye, digits, and jaw.


Assuntos
Encéfalo/anormalidades , Anormalidades do Olho/genética , Dedos/anormalidades , Mutação de Sentido Incorreto , Fenótipo , Ubiquitina-Proteína Ligases/genética , Proteínas Contendo Repetições de beta-Transducina/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino
11.
Dig Dis Sci ; 67(2): 437-444, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34731362

RESUMO

Multiple primary malignant neoplasms (MPMN) represent the occurrence of a second malignancy in the same patient within 6 months after the detection of first primary (synchronous) tumor, or > 6 months after primary detection (metachronous). We present a case of a patient treated for carcinoma of the breast who developed a metachronous primary malignancy in the colorectal tract. These tumors were histologically different with distinct immune-histochemical parameters. The association between breast and colon cancer is well documented in the literature with several studies reporting the coexistence of common extrinsic and genetic predisposing factors. Although rare, MPMN are becoming more common due to the increased number of elderly cancer survivors, improved diagnosis and enhanced awareness. The association between colorectal and breast cancer should not be dismissed merely as metastasis since there is good precedent for the co-occurrence of these primary tumors.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Adenocarcinoma/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Neoplasias Colorretais/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/patologia , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
12.
Sensors (Basel) ; 22(16)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36015722

RESUMO

In this paper, the use of a phase-sensitive optical time-domain reflectometry (ϕ-OTDR) sensor for the detection of the Lamb waves excited by a piezoelectric transducer in an aluminum plate, is investigated. The system is shown to detect and resolve the Lamb wave in distinct regions of the plate, opening the possibility of realizing structural health monitoring (SHM) and damage detection using a single optical fiber attached to the structure. The system also reveals the variations in the Lamb wave resulting from a change in the load conditions of the plate. The same optical fiber used to detect the Lamb waves has also been employed to realize distributed strain measurements using a Brillouin scattering system. The method can be potentially used to replace conventional SHM sensors such as strain gauges and PZT transducers, with the advantage of offering several sensing points using a single fiber.


Assuntos
Fibras Ópticas , Transdutores
13.
Hum Mol Genet ; 28(13): 2133-2142, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30806661

RESUMO

Hereditary multiple osteochondromas (HMO) is a rare autosomal dominant skeletal disorder, caused by heterozygous variants in either EXT1 or EXT2, which encode proteins involved in the biogenesis of heparan sulphate. Pathogenesis and genotype-phenotype correlations remain poorly understood. We studied 114 HMO families (158 affected individuals) with causative EXT1 or EXT2 variants identified by Sanger sequencing, or multiplex ligation-dependent probe amplification and qPCR. Eighty-seven disease-causative variants (55 novel and 32 known) were identified including frameshift (42%), nonsense (32%), missense (11%), splicing (10%) variants and genomic rearrangements (5%). Informative clinical features were available for 42 EXT1 and 27 EXT2 subjects. Osteochondromas were more frequent in EXT1 as compared to EXT2 patients. Anatomical distribution of lesions showed significant differences based on causative gene. Microscopy analysis for selected EXT1 and EXT2 variants verified that EXT1 and EXT2 mutants failed to co-localize each other and loss Golgi localization by surrounding the nucleus and/or assuming a diffuse intracellular distribution. In a cell viability study, cells expressing EXT1 and EXT2 mutants proliferated more slowly than cells expressing wild-type proteins. This confirms the physiological relevance of EXT1 and EXT2 Golgi co-localization and the key role of these proteins in the cell cycle. Taken together, our data expand genotype-phenotype correlations, offer further insights in the pathogenesis of HMO and open the path to future therapies.


Assuntos
Exostose Múltipla Hereditária/genética , N-Acetilglucosaminiltransferases/genética , Proliferação de Células , Sobrevivência Celular , Feminino , Estudos de Associação Genética , Complexo de Golgi/enzimologia , Células HEK293 , Humanos , Masculino , Mutação , N-Acetilglucosaminiltransferases/análise
14.
Ann Hum Genet ; 85(6): 249-252, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34075583

RESUMO

Brain malformations have been reported in RASopathies, including postnatal external hydrocephalus, a nonobstructive form of cerebrospinal fluid accumulation around the brain. It was described in a few patients with mutations of other genes than PTPN11, such as SOS1 and SHOC2 and never in prenatal diagnosis. The aim of this case report is to describe the prenatal presentation of a fetus with Noonan syndrome (NS) and external hydrocephalus. We report on a Noonan syndrome fetus with a de novo pathogenic PTPN11 c.923A>G p.Asn308Ser mutation, showing external hydrocephalus, an extremely rare fetal finding, corpus callosum, and cerebellar vermis under the 10th centile, plus a typical NS cardiopathy. This is the first case of Noonan syndrome prenatal diagnosis in a fetus presenting with external hydrocephalus. Following pathophysiological considerations, we suggest to consider NS in the differential diagnosis of external hydrocephalus, investigating other evocative findings and considering molecular screening for mutations in NS-related genes.


Assuntos
Hidrocefalia/diagnóstico , Síndrome de Noonan/diagnóstico , Feminino , Humanos , Mutação , Síndrome de Noonan/genética , Gravidez , Diagnóstico Pré-Natal , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética
15.
Am J Hum Genet ; 102(1): 69-87, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29290338

RESUMO

Neurofibromatosis type 1 (NF1), a common genetic disorder with a birth incidence of 1:2,000-3,000, is characterized by a highly variable clinical presentation. To date, only two clinically relevant intragenic genotype-phenotype correlations have been reported for NF1 missense mutations affecting p.Arg1809 and a single amino acid deletion p.Met922del. Both variants predispose to a distinct mild NF1 phenotype with neither externally visible cutaneous/plexiform neurofibromas nor other tumors. Here, we report 162 individuals (129 unrelated probands and 33 affected relatives) heterozygous for a constitutional missense mutation affecting one of five neighboring NF1 codons-Leu844, Cys845, Ala846, Leu847, and Gly848-located in the cysteine-serine-rich domain (CSRD). Collectively, these recurrent missense mutations affect ∼0.8% of unrelated NF1 mutation-positive probands in the University of Alabama at Birmingham (UAB) cohort. Major superficial plexiform neurofibromas and symptomatic spinal neurofibromas were more prevalent in these individuals compared with classic NF1-affected cohorts (both p < 0.0001). Nearly half of the individuals had symptomatic or asymptomatic optic pathway gliomas and/or skeletal abnormalities. Additionally, variants in this region seem to confer a high predisposition to develop malignancies compared with the general NF1-affected population (p = 0.0061). Our results demonstrate that these NF1 missense mutations, although located outside the GAP-related domain, may be an important risk factor for a severe presentation. A genotype-phenotype correlation at the NF1 region 844-848 exists and will be valuable in the management and genetic counseling of a significant number of individuals.


Assuntos
Códon/genética , Estudos de Associação Genética , Mutação de Sentido Incorreto/genética , Neurofibromatose 1/genética , Neurofibromina 1/genética , Adolescente , Sequência de Aminoácidos , Criança , Estudos de Coortes , Simulação por Computador , Demografia , Feminino , Heterozigoto , Humanos , Masculino , Neurofibromina 1/química , Fenótipo , Adulto Jovem
16.
Genet Med ; 23(6): 1116-1124, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33568805

RESUMO

PURPOSE: Recent studies have identified suggestive prenatal features of RASopathies (e.g., increased nuchal translucency [NT], cystic hygroma [CH], hydrops, effusions, congenital heart diseases [CHD], polyhydramnios, renal anomalies). Our objective is to clarify indications for RASopathy prenatal testing. We compare genotype distributions between pre- and postnatal populations and propose genotype-phenotype correlations. METHODS: Three hundred fifty-two chromosomal microarray-negative cases sent for prenatal RASopathy testing between 2012 and 2019 were collected. For most, 11 RASopathy genes were tested. Postnatal cohorts (25 patients with available prenatal information and 108 institutional database genotypes) and the NSeuroNet database were used for genotypic comparisons. RESULTS: The overall diagnostic yield was 14% (50/352), with rates >20% for effusions, hydrops, and CHD. Diagnostic yield was significantly improved in presence of hypertrophic cardiomyopathy (HCM), persistent or associated CH, any suggestive finding combined with renal anomaly or polyhydramnios, or ≥2 ultrasound findings. Largest prenatal contributors of pathogenic variants were PTPN11 (30%), RIT1 (16%), RAF1 (14%), and HRAS (12%), which considerably differ from their prevalence in postnatal populations. HRAS, LZTR1, and RAF1 variants correlated with hydrops/effusions, and RIT1 with prenatal onset HCM. CONCLUSION: After normal chromosomal microarray, RASopathies should be considered when any ultrasound finding of lymphatic dysplasia or suggestive CHD is found alone or in association.


Assuntos
Cardiopatias Congênitas , Medição da Translucência Nucal , Estudos de Coortes , Feminino , Feto , Estudos de Associação Genética , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/genética , Humanos , Gravidez , Fatores de Transcrição , Ultrassonografia Pré-Natal
17.
Clin Genet ; 100(5): 563-572, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34346503

RESUMO

Neurofibromatosis 1 (NF1) is a disorder characterized by variable expressivity caused by loss-of-function variants in NF1, encoding neurofibromin, a protein negatively controlling RAS signaling. We evaluated whether concurrent variation in proteins functionally linked to neurofibromin contribute to the variable expressivity of NF1. Parallel sequencing of a RASopathy gene panel in 138 individuals with molecularly confirmed clinical diagnosis of NF1 identified missense variants in PTPN11, encoding SHP2, a positive regulator of RAS signaling, in four subjects from three unrelated families. Three subjects were heterozygous for a gain-of-function variant and showed a severe expression of NF1 (developmental delay, multiple cerebral neoplasms and peculiar cortical MRI findings), and features resembling Noonan syndrome (a RASopathy caused by activating variants in PTPN11). Conversely, the fourth subject, who showed an attenuated presentation, carried a previously unreported PTPN11 variant that had a hypomorphic behavior in vitro. Our findings document that functionally relevant PTPN11 variants occur in a small but significant proportion of subjects with NF1 modulating disease presentation, suggesting a model in which the clinical expression of pathogenic NF1 variants is modified by concomitant dysregulation of protein(s) functionally linked to neurofibromin. We also suggest targeting of SHP2 function as an approach to treat evolutive complications of NF1.


Assuntos
Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Mutação , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Adolescente , Criança , Análise Mutacional de DNA , Família , Feminino , Genes da Neurofibromatose 1 , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Modelos Moleculares , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Conformação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 11/química , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Relação Estrutura-Atividade
18.
Clin Genet ; 100(3): 268-279, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33988253

RESUMO

Oculo-auriculo-vertebral spectrum (OAVS) is a developmental disorder of craniofacial morphogenesis. Its etiology is unclear, but assumed to be complex and heterogeneous, with contribution of both genetic and environmental factors. We assessed the occurrence of copy number variants (CNVs) in a cohort of 19 unrelated OAVS individuals with congenital heart defect. Chromosomal microarray analysis identified pathogenic CNVs in 2/19 (10.5%) individuals, and CNVs classified as variants of uncertain significance in 7/19 (36.9%) individuals. Remarkably, two subjects had small intragenic CNVs involving DACH1 and DACH2, two paralogs coding for key components of the PAX-SIX-EYA-DACH network, a transcriptional regulatory pathway controlling developmental processes relevant to OAVS and causally associated with syndromes characterized by craniofacial involvement. Moreover, a third patient showed a large duplication encompassing DMBX1/OTX3, encoding a transcriptional repressor of OTX2, another transcription factor functionally connected to the DACH-EYA-PAX network. Among the other relevant CNVs, a deletion encompassing HSD17B6, a gene connected with the retinoic acid signaling pathway, whose dysregulation has been implicated in craniofacial malformations, was also identified. Our findings suggest that CNVs affecting gene dosage likely contribute to the genetic heterogeneity of OAVS, and implicate the PAX-SIX-EYA-DACH network as novel pathway involved in the etiology of this developmental trait.


Assuntos
Variações do Número de Cópias de DNA , Síndrome de Goldenhar/genética , Cardiopatias Congênitas/genética , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Síndrome de Goldenhar/fisiopatologia , Humanos , Lactente , Recém-Nascido , Masculino , Análise em Microsséries , Polimorfismo de Nucleotídeo Único , Adulto Jovem
19.
World J Surg Oncol ; 19(1): 93, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33781279

RESUMO

BACKGROUND: In the last decade, two research groups, the French group by Clough et al. (Br J Surg. 97:1659-65, 2010) and the Chinese one by Li et al. (ISRN Oncol 2013:279013, 2013), proposed two types of classification of axillary lymph nodes in breast cancer, identifying novel anatomic landmarks for dividing the axillary space in lymph node dissection. MAIN BODY: Knowledge of the exact location of the sentinel node helps to focus the surgical dissection and to reduce the morbidity of sentinel lymph node biopsy procedures, in particular the risk of arm lymphedema, without compromising sensitivity. CONCLUSION: In this article, we aimed at focusing on the clinical impact that the most recent classifications of axillary lymph nodes have obtained in literature, highlighting the importance of defining new demarcations to preserve the axillary lymph nodes as much as possible in breast surgery.


Assuntos
Neoplasias da Mama , Linfonodos , Axila , Neoplasias da Mama/cirurgia , Humanos , Excisão de Linfonodo , Linfonodos/cirurgia , Metástase Linfática , Prognóstico , Biópsia de Linfonodo Sentinela
20.
Int J Mol Sci ; 22(4)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567536

RESUMO

The expanded CAG repeat number in HTT gene causes Huntington disease (HD), which is a severe, dominant neurodegenerative illness. The accurate determination of the expanded allele size is crucial to confirm the genetic status in symptomatic and presymptomatic at-risk subjects and avoid genetic polymorphism-related false-negative diagnoses. Precise CAG repeat number determination is critical to discriminate the cutoff between unexpanded and intermediate mutable alleles (IAs, 27-35 CAG) as well as between IAs and pathological, low-penetrance alleles (i.e., 36-39 CAG repeats), and it is also critical to detect large repeat expansions causing pediatric HD variants. We analyzed the HTT-CAG repeat number of 14 DNA reference materials and of a DNA collection of 43 additional samples carrying unexpanded, IAs, low and complete penetrance alleles, including large (>60 repeats) and very large (>100 repeats) expansions using a novel triplet-primed PCR-based assay, the AmplideX PCR/CE HTT Kit. The results demonstrate that the method accurately genotypes both normal and expanded HTT-CAG repeat numbers and reveals previously undisclosed and very large CAG expansions >200 repeats. We also show that this technique can improve genetic test reliability and accuracy by detecting CAG expansions in samples with sequence variations within or adjacent to the repeat tract that cause allele drop-outs or inaccuracies using other PCR methods.


Assuntos
Testes Genéticos/métodos , Proteína Huntingtina/genética , Doença de Huntington/diagnóstico , Reação em Cadeia da Polimerase/métodos , Repetições de Trinucleotídeos , Estudos de Coortes , Humanos , Doença de Huntington/genética
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