RESUMO
We previously molecularly and clinically characterized Mazzanti syndrome, a RASopathy related to Noonan syndrome that is mostly caused by a single recurrent missense variant (c.4A > G, p.Ser2Gly) in SHOC2, which encodes a leucine-rich repeat-containing protein facilitating signal flow through the RAS-mitogen-associated protein kinase (MAPK) pathway. We also documented that the pathogenic p.Ser2Gly substitution causes upregulation of MAPK signaling and constitutive targeting of SHOC2 to the plasma membrane due to the introduction of an N-myristoylation recognition motif. The almost invariant occurrence of the pathogenic c.4A > G missense change in SHOC2 is mirrored by a relatively homogeneous clinical phenotype of Mazzanti syndrome. Here, we provide new data on the clinical spectrum and molecular diversity of this disorder and functionally characterize new pathogenic variants. The clinical phenotype of six unrelated individuals carrying novel disease-causing SHOC2 variants is delineated, and public and newly collected clinical data are utilized to profile the disorder. In silico, in vitro and in vivo characterization of the newly identified variants provides evidence that the consequences of these missense changes on SHOC2 functional behavior differ from what had been observed for the canonical p.Ser2Gly change but converge toward an enhanced activation of the RAS-MAPK pathway. Our findings expand the molecular spectrum of pathogenic SHOC2 variants, provide a more accurate picture of the phenotypic expression associated with variants in this gene and definitively establish a gain-of-function behavior as the mechanism of disease.
Assuntos
Anormalidades Múltiplas , Peptídeos e Proteínas de Sinalização Intracelular , Síndrome dos Cabelos Anágenos Frouxos , Anormalidades Múltiplas/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Síndrome dos Cabelos Anágenos Frouxos/genética , Fenótipo , Proteínas ras/genética , Proteínas ras/metabolismoRESUMO
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/genéticaRESUMO
The evaluation of endocrine involvement in RASopathies is important for the care and follow-up of patients affected by these conditions. Short stature is a cardinal feature of RASopathies and correlates with multiple factors. Growth hormone treatment is a therapeutic possibility to improve height and quality of life. Assessment of growth rate and growth laboratory parameters is routine, but age at start of therapy, dose and effects of growth hormone on final height need to be clarified. Puberty disorders and gonadal dysfunction, in particular in males, are other endocrinological areas to evaluate for their effects on growth and development. Thyroid dysfunction, autoimmune disease and bone involvement have also been reported in RASopathies. In this brief review, we describe the current knowledge on growth, growth hormone therapy, endocrinological involvement in patients affected by RASopathies.
Assuntos
Hormônio do Crescimento Humano , Qualidade de Vida , Masculino , Humanos , Hormônio do Crescimento/farmacologia , Hormônio do Crescimento/uso terapêutico , Hormônio do Crescimento Humano/uso terapêutico , Puberdade , EstaturaRESUMO
Over a relatively short period of time, the clinical geneticist's "toolbox" has been expanded by machine-learning algorithms for image analysis, which can be applied to the task of syndrome identification on the basis of facial photographs, but these technologies harbor potential beyond the recognition of established phenotypes. Here, we comprehensively characterized two individuals with a hitherto unknown genetic disorder caused by the same de novo mutation in LEMD2 (c.1436C>T;p.Ser479Phe), the gene which encodes the nuclear envelope protein LEM domain-containing protein 2 (LEMD2). Despite different ages and ethnic backgrounds, both individuals share a progeria-like facial phenotype and a distinct combination of physical and neurologic anomalies, such as growth retardation; hypoplastic jaws crowded with multiple supernumerary, yet unerupted, teeth; and cerebellar intention tremor. Immunofluorescence analyses of patient fibroblasts revealed mutation-induced disturbance of nuclear architecture, recapitulating previously published data in LEMD2-deficient cell lines, and additional experiments suggested mislocalization of mutant LEMD2 protein within the nuclear lamina. Computational analysis of facial features with two different deep neural networks showed phenotypic proximity to other nuclear envelopathies. One of the algorithms, when trained to recognize syndromic similarity (rather than specific syndromes) in an unsupervised approach, clustered both individuals closely together, providing hypothesis-free hints for a common genetic etiology. We show that a recurrent de novo mutation in LEMD2 causes a nuclear envelopathy whose prognosis in adolescence is relatively good in comparison to that of classical Hutchinson-Gilford progeria syndrome, and we suggest that the application of artificial intelligence to the analysis of patient images can facilitate the discovery of new genetic disorders.
Assuntos
Proteínas de Membrana/genética , Mutação , Proteínas Nucleares/genética , Progéria/genética , Adolescente , Inteligência Artificial , Linhagem Celular Tumoral , Núcleo Celular , Criança , Pré-Escolar , Diagnóstico por Computador , Face , Fibroblastos/metabolismo , Humanos , Masculino , Programas de Rastreamento/métodos , Informática Médica , Fenótipo , Prognóstico , SíndromeRESUMO
Pasta is one of the components of the Mediterranean Diet, despite considerable attention given, its use is still debated. Several studies encouraged the consumption of whole grain because of its many properties and the positive association between refined carbohydrates and insulin resistance, by measuring the Glycaemic Index (GI), an indicator of the physiological effects of a carbohydrate meal. In this study, the GI and polyphenol content of Senatore Cappelli (Triticum turgidum ssp. durum) pasta were evaluated. Using spectrophotometric methods, total polyphenols and flavonoids were found to be 113.5 mg/100 g and 52.96 mg/100 g, respectively. To measure the GI, a standard assay was performed, and values of 47.9 ± 5.2 for long format pasta and 68.5 ± 4.6 for short format pasta were obtained. The present study confirms the presence of polyphenols and flavonoids in pasta Senatore Cappelli. The value of GI is influenced by the pasta shape. These informations could provide valuable data for practitioners preparing personalised diets.
Assuntos
Triticum , Grãos Integrais , Farinha/análise , Valor Nutritivo , PolifenóisRESUMO
Bone dysplasias (osteochondrodysplasias) are a large group of conditions associated with short stature, skeletal disproportion, and radiographic abnormalities of skeletal elements. Nearly all are genetic in origin. We report a series of seven children with similar findings of chondrodysplasia and growth failure following early hematopoietic stem cell transplantation (HSCT) for pediatric non-oncologic disease: hemophagocytic lymphohistiocytosis or HLH (five children, three with biallelic HLH-associated variants [in PRF1 and UNC13D] and one with HLH secondary to visceral Leishmaniasis), one child with severe combined immunodeficiency and one with Omenn syndrome (both children had biallelic RAG1 pathogenic variants). All children had normal growth and no sign of chondrodysplasia at birth and prior to their primary disease. After HSCT, all children developed growth failure, with standard deviation scores for height at or below -3. Radiographically, all children had changes in the spine, metaphyses and epiphyses, compatible with a spondyloepimetaphyseal dysplasia. Genomic sequencing failed to detect pathogenic variants in genes associated with osteochondrodysplasias. We propose that such chondrodysplasia with growth failure is a novel, rare, but clinically important complication following early HSCT for non-oncologic pediatric diseases. The pathogenesis is unknown but could possibly involve loss or perturbation of the cartilage-bone stem cell population.
Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Linfo-Histiocitose Hemofagocítica/genética , Osteocondrodisplasias/genética , Criança , Pré-Escolar , Feminino , Humanos , Linfo-Histiocitose Hemofagocítica/complicações , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/terapia , Masculino , Proteínas de Membrana/genética , Osteocondrodisplasias/complicações , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/terapia , Perforina/genética , Resultado do TratamentoRESUMO
PURPOSE: Taste changes due to chemotherapy may contribute to the high prevalence of malnutrition in cancer patients. It is believed that 50-70% of patients with cancer suffer from taste disorders. The aim of the present study was to analyze the taste alterations in patient population compared with that in controls, also in relation to gender. In this way, it could open to a new approach for a personalized diet to prevent and/or reduce taste alterations and malnutrition in cancer patients. METHODS: Forty-five cancer patients undergoing chemotherapy were compared with healthy controls (n = 32). Taste function test was used to determine taste sensitivity. Different concentrations for each of the four basic tastes (salty, sweet, sour, bitter) and also fat and water tastes were evaluated. RESULTS: A significant difference in taste sensitivity between patients and control group was found, in line with previous similar studies. As in the control group, taste perception in patients was better in females than in males, suggesting interaction effect between group and gender. CONCLUSIONS: Coping strategies regarding subjective taste impairment should be provided since alterations in taste sensitivity influence food preferences and appetite. Clinicians could thus have the potential to underpin changes in dietary intake and consequently in nutritional status; understanding the extent of the contribution of each taste would help in the development of effective interventions in future. Consequently, patients can adopt appropriate appetizing strategies and, based on that, change their feeding habits.
Assuntos
Antineoplásicos/efeitos adversos , Disgeusia/diagnóstico , Neoplasias/patologia , Distúrbios do Paladar/fisiopatologia , Percepção Gustatória/fisiologia , Adulto , Antineoplásicos/uso terapêutico , Apetite , Dieta , Feminino , Preferências Alimentares , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Caracteres Sexuais , PaladarRESUMO
We report a patient with developmental delay, brachydactyly type E, short stature, and tetralogy of Fallot. Brachydactyly-mental retardation syndrome (BDMR) was suspected based on the phenotype; however, array CGH excluded a 2q37 deletion, but identified a deletion encompassing the SHOX gene. BDMR is characterized by cognitive impairment, skeletal abnormalities involving hands and feet, short stature, and overweight. Most affected individuals carry relatively large 2q37 deletions encompassing HDAC4. This gene encodes a histone deacetylase involved in epigenetic regulation of cell growth and differentiation, specifically during endochondral bone formation in chondrocyte hypertrophy. Since SHOX haploinsufficiency can cause skeletal defects and short stature but would not fully explain the clinical picture of this patient, exome sequencing was performed, and a heterozygous HDAC8 frameshift mutation was identified. HDAC8 is a distinct histone deacetylase involved in cohesin recycling and is responsible for an X-linked dominant Cornelia de Lange-like phenotype. A new blended clinical phenotype may be explained by the result of a dual molecular diagnosis, which represents a combination of 2 independent genetic defects, with relevant implications for genetic counseling, clinical management, and prognosis.
Assuntos
Síndrome de Cornélia de Lange/diagnóstico , Mutação da Fase de Leitura , Deleção de Genes , Transtornos do Crescimento/diagnóstico , Histona Desacetilases/genética , Osteocondrodisplasias/diagnóstico , Proteínas Repressoras/genética , Proteína de Homoeobox de Baixa Estatura/genética , Criança , Hibridização Genômica Comparativa , Síndrome de Cornélia de Lange/genética , Feminino , Transtornos do Crescimento/genética , Haploinsuficiência , Humanos , Osteocondrodisplasias/genética , Linhagem , Fenótipo , Sequenciamento do ExomaRESUMO
An adequate placental vascularization allows the proper development of the fetus and it is crucial for the gestational success. A number of factors regulate angiogenesis, including vascular endothelial growth factor (VEGF), which induces the synthesis of nitric oxide (NO), a potent vasodilator produced by three different nitric oxide synthase (NOS) isoforms. NO is essential to maintain a low vascular resistance in the fetoplacental circulation, although at high concentrations, it may combine with excess superoxide to produce peroxynitrite, which reacts with proteins giving rise to nitrotyrosine. Since obesity, whose incidence is increasing worldwide, is characterized by a low-grade inflammatory state and increased levels of oxidative and nitrative stress, both affecting placental function, our aim was to evaluate the expression of VEGF, eNOS, and iNOS in full-term placentas obtained from normal weight and pre-pregnancy obese women by means of immunohistochemistry and real-time PCR. Moreover, we assessed the NO levels and the nitrotyrosine immunoexpression in the same sample groups. Our results show a significantly higher immunohistochemical expression of VEGF and eNOS in the endothelium of placentas from obese women than in controls, whereas the immunoexpression of iNOS was comparable in the two groups. These data agree with those of the gene expression analysis, thus suggesting the possible existence of a compensatory mechanism for changes in placental blood flow associated with obesity. As concerns nitrotyrosine and NO levels, we observed a significant increase in placental tissue from obese women which may contribute to the development of metabolic and cardiovascular diseases both in the mother and the offspring.
Assuntos
Óxido Nítrico Sintase/genética , Obesidade/metabolismo , Placenta/química , Fatores de Crescimento do Endotélio Vascular/genética , Adulto , Feminino , Humanos , Imuno-Histoquímica , Óxido Nítrico/análise , Óxido Nítrico Sintase/metabolismo , Placenta/metabolismo , Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Tirosina/análogos & derivados , Tirosina/análise , Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
PURPOSE: Recently, there was an increasing interest on the use of ancient grains because of their better health-related composition. The aim of this study was to evaluate in healthy human subjects the antioxidative and diabetes-preventive properties of ancient KAMUT® khorasan wheat compared to modern wheat. METHODS: The study was a randomized, non-blind, parallel arm study where the biochemical parameters of volunteers with a diet based on organic whole grain KAMUT® khorasan products, as the only source of cereal products were compared to a similar replacement diet based on organic whole grain modern durum wheat products. A total of 30 healthy volunteers were recruited and the intervention period lasted 16 weeks. Blood analyses were performed before and after the diet intervention. The effect of KAMUT® khorasan products on biochemical parameters was analyzed by multiple quantile regression adjusted for age, sex, physical activity and BMI compared to data at baseline. RESULTS: Subjects receiving KAMUT® khorasan products showed a significantly greater decrease of fat mass (b = 3.7%; CI 1.6-5.5; p = 0.042), insulin (b = 2.4 µU/ml; CI 0.2-4.2; p = 0.036) and a significant increase of DHA (b = - 0.52%; CI - 1.1 to - 0.12; p = 0.021). CONCLUSIONS: Our study provides evidence that a substitution diet with KAMUT® khorasan wheat products can reduce some markers associated to the development of type-2 diabetes compared to a diet of modern wheat.
Assuntos
Antioxidantes/farmacologia , Diabetes Mellitus Tipo 2/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Triticum , Adulto , Grão Comestível , Feminino , Voluntários Saudáveis , Humanos , Masculino , Projetos Piloto , Valores de ReferênciaRESUMO
Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to and degrades the low-density lipoprotein receptor (LDLR), contributing to hypercholesterolemia. Adipose tissue plays a role in lipoprotein metabolism, but there are almost no data about PCSK9 and LDLR regulation in human adipocytes. We studied PCSK9 and LDLR regulation by insulin, atrial natriuretic peptide (ANP, a potent lipolytic agonist that antagonizes insulin), and LDL in visceral adipose tissue (VAT) and in human cultured adipocytes. PCSK9 was expressed in VAT and its expression was positively correlated with body mass index (BMI). Both intracellular mature and secreted PCSK9 were abundant in cultured human adipocytes. Insulin induced PCSK9, LDLR, and sterol-regulatory element-binding protein-1c (SREBP-1c) and -2 expression (SREBP-2). ANP reduced insulin-induced PCSK9, especially in the context of a medium simulating hyperglycemia. Human LDL induced both mature and secreted PCSK9 and reduced LDLR. ANP indirectly blocked the LDLR degradation, reducing the positive effect of LDL on PCSK9. In conclusion, PCSK9 is expressed in human adipocytes. When the expression of PCSK9 is induced, LDLR is reduced through the PCSK9-mediated degradation. On the contrary, when the induction of PCSK9 by insulin and LDL is partially blocked by ANP, the LDLR degradation is reduced. This suggests that NPs could be able to control LDLR levels, preventing PCSK9 overexpression.
Assuntos
Tecido Adiposo/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Insulina/farmacologia , Peptídeos Natriuréticos/farmacologia , Pró-Proteína Convertase 9/genética , Adipócitos/metabolismo , Idoso , Biomarcadores , LDL-Colesterol/sangue , Feminino , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Receptores de LDL/metabolismoRESUMO
Ablepharon macrostomia syndrome (AMS) and Barber-Say syndrome (BSS) are rare congenital ectodermal dysplasias characterized by similar clinical features. To establish the genetic basis of AMS and BSS, we performed extensive clinical phenotyping, whole exome and candidate gene sequencing, and functional validations. We identified a recurrent de novo mutation in TWIST2 in seven independent AMS-affected families, as well as another recurrent de novo mutation affecting the same amino acid in ten independent BSS-affected families. Moreover, a genotype-phenotype correlation was observed, because the two syndromes differed based solely upon the nature of the substituting amino acid: a lysine at TWIST2 residue 75 resulted in AMS, whereas a glutamine or alanine yielded BSS. TWIST2 encodes a basic helix-loop-helix transcription factor that regulates the development of mesenchymal tissues. All identified mutations fell in the basic domain of TWIST2 and altered the DNA-binding pattern of Flag-TWIST2 in HeLa cells. Comparison of wild-type and mutant TWIST2 expressed in zebrafish identified abnormal developmental phenotypes and widespread transcriptome changes. Our results suggest that autosomal-dominant TWIST2 mutations cause AMS or BSS by inducing protean effects on the transcription factor's DNA binding.
Assuntos
Anormalidades Múltiplas/genética , Anormalidades do Olho/genética , Doenças Palpebrais/genética , Hirsutismo/genética , Hipertelorismo/genética , Hipertricose/genética , Macrostomia/genética , Modelos Moleculares , Fenótipo , Proteínas Repressoras/genética , Anormalidades da Pele/genética , Proteína 1 Relacionada a Twist/genética , Anormalidades Múltiplas/patologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Imunoprecipitação da Cromatina , Exoma/genética , Anormalidades do Olho/patologia , Doenças Palpebrais/patologia , Células HeLa , Hirsutismo/patologia , Humanos , Hipertelorismo/patologia , Hipertricose/patologia , Macrostomia/patologia , Microscopia Eletrônica , Dados de Sequência Molecular , Mutação de Sentido Incorreto/genética , Conformação Proteica , Proteínas Repressoras/química , Análise de Sequência de DNA , Anormalidades da Pele/patologia , Proteína 1 Relacionada a Twist/química , Peixe-ZebraRESUMO
Uterine fibroids are the most common neoplasm of the genital tract in reproductive women. Obesity holds a role as risk factor for uterine fibroids, through hormonal and inflammatory mechanisms. Visceral fat is a hormonally active tissue, so an increase in visceral fat may be considered as a risk factor, through the increased production of inflammatory mediators. The aim of the study was, therefore, to evaluate the association between the presence of uterine fibroids and fat tissue distribution, and to assess the efficacy of both anthropometric and instrumental indicators, in particular the sonographic measurement of preperitoneal fat thickness (PFT) and subcutaneous fat thickness (SFT). Study group consisted of childbearing-age women with at least one uterine fibroid with a diameter ≥10 mm (n = 71), all the childbearing-age women who access to the outpatient service of our institution in the same period, without evidence of uterine fibroids, constituted the control group (n = 145). A significantly difference in BMI (p = 0.0034), PFT (p < 0.0001), and SFT (p = 0.0003) emerged. At the multivariate analysis, only PFT showed an independent significant association with the presence of uterine fibroids (p < 0.0001). The ROC curve analysis identified a cut-off value of 6.7 mm of PFT as discriminator for the presence of uterine fibroids.
Assuntos
Adiposidade , Gordura Intra-Abdominal/diagnóstico por imagem , Leiomioma/diagnóstico por imagem , Leiomiomatose/diagnóstico por imagem , Obesidade Abdominal/diagnóstico por imagem , Neoplasias Uterinas/diagnóstico por imagem , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Itália/epidemiologia , Leiomioma/epidemiologia , Leiomioma/etiologia , Leiomiomatose/epidemiologia , Leiomiomatose/etiologia , Análise Multivariada , Obesidade Abdominal/fisiopatologia , Curva ROC , Fatores de Risco , Gordura Subcutânea Abdominal/diagnóstico por imagem , Ultrassonografia , Neoplasias Uterinas/epidemiologia , Neoplasias Uterinas/etiologia , Relação Cintura-QuadrilRESUMO
BACKGROUND: The normobaric oxygen paradox states that a short exposure to normobaric hyperoxia followed by rapid return to normoxia creates a condition of 'relative hypoxia' which stimulates erythropoietin (EPO) production. Alterations in glutathione and reactive oxygen species (ROS) may be involved in this process. We tested the effects of short-term hyperoxia on EPO levels and the microcirculation in critically ill patients. METHODS: In this prospective, observational study, 20 hemodynamically stable, mechanically ventilated patients with inspired oxygen concentration (FiO2) ≤0.5 and PaO2/FiO2 ≥ 200 mmHg underwent a 2-hour exposure to hyperoxia (FiO2 1.0). A further 20 patients acted as controls. Serum EPO was measured at baseline, 24 h and 48 h. Serum glutathione (antioxidant) and ROS levels were assessed at baseline (t0), after 2 h of hyperoxia (t1) and 2 h after returning to their baseline FiO2 (t2). The microvascular response to hyperoxia was assessed using sublingual sidestream dark field videomicroscopy and thenar near-infrared spectroscopy with a vascular occlusion test. RESULTS: EPO increased within 48 h in patients exposed to hyperoxia from 16.1 [7.4-20.2] to 22.9 [14.1-37.2] IU/L (p = 0.022). Serum ROS transiently increased at t1, and glutathione increased at t2. Early reductions in microvascular density and perfusion were seen during hyperoxia (perfused small vessel density: 85% [95% confidence interval 79-90] of baseline). The response after 2 h of hyperoxia exposure was heterogeneous. Microvascular perfusion/density normalized upon returning to baseline FiO2. CONCLUSIONS: A two-hour exposure to hyperoxia in critically ill patients was associated with a slight increase in EPO levels within 48 h. Adequately controlled studies are needed to confirm the effect of short-term hyperoxia on erythropoiesis. TRIAL REGISTRATION: ClinicalTrials.gov ( www.clinicaltrials.gov ), NCT02481843 , registered 15th June 2015, retrospectively registered.
Assuntos
Estado Terminal , Eritropoetina/sangue , Hiperóxia/sangue , Hiperóxia/fisiopatologia , Microcirculação/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Glutationa/sangue , Hemodinâmica/fisiologia , Humanos , Masculino , Microscopia de Vídeo , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Espécies Reativas de Oxigênio/sangue , Espectroscopia de Luz Próxima ao InfravermelhoRESUMO
Rubinstein-Taybi syndrome (RSTS) is a rare congenital neurodevelopmental disorder characterized by growth deficiency, skeletal abnormalities, dysmorphic features, and intellectual disability. Causative mutations in CREBBP and EP300 genes have been identified in â¼55% and â¼8% of affected individuals. To date, only 28 EP300 alterations in 29 RSTS clinically described patients have been reported. EP300 analysis of 22 CREBBP-negative RSTS patients from our cohort led us to identify six novel mutations: a 376-kb deletion depleting EP300 gene; an exons 17-19 deletion (c.(3141+1_3142-1)_(3590+1_3591-1)del/p.(Ile1047Serfs*30)); two stop mutations, (c.3829A>T/p.(Lys1277*) and c.4585C>T/p.(Arg1529*)); a splicing mutation (c.1878-12A>G/p.(Ala627Glnfs*11)), and a duplication (c.4640dupA/p.(Asn1547Lysfs*3)). All EP300-mutated individuals show a mild RSTS phenotype and peculiar findings including maternal gestosis, skin manifestation, especially nevi or keloids, back malformations, and a behavior predisposing to anxiety. Furthermore, the patient carrying the complete EP300 deletion does not show a markedly severe clinical picture, even if a more composite phenotype was noticed. By characterizing six novel EP300-mutated patients, this study provides further insights into the EP300-specific clinical presentation and expands the mutational repertoire including the first case of a whole gene deletion. These new data will enhance EP300-mutated cases identification highlighting distinctive features and will improve the clinical practice allowing a better genotype-phenotype correlation.
Assuntos
Proteína p300 Associada a E1A/genética , Genoma Humano , Mutação , Síndrome de Rubinstein-Taybi/genética , Adolescente , Proteína de Ligação a CREB/genética , Criança , Feminino , Expressão Gênica , Estudos de Associação Genética , Variação Genética , Humanos , Hibridização in Situ Fluorescente , Masculino , Fenótipo , Síndrome de Rubinstein-Taybi/patologia , Análise de Sequência de DNA , Adulto JovemRESUMO
Loss-of-function mutations in PAK3 contribute to non-syndromic X-linked intellectual disability (NS-XLID) by affecting dendritic spine density and morphology. Linkage analysis in a three-generation family with affected males showing ID, agenesis of corpus callosum, cerebellar hypoplasia, microcephaly and ichthyosis, revealed a candidate disease locus in Xq21.33q24 encompassing over 280 genes. Subsequent to sequencing all coding exons of the X chromosome, we identified a single novel variant within the linkage region, affecting a conserved codon of PAK3. Biochemical studies showed that, similar to previous NS-XLID-associated lesions, the predicted amino acid substitution (Lys389Asn) abolished the kinase activity of PAK3. In addition, the introduced residue conferred a dominant-negative function to the protein that drives the syndromic phenotype. Using a combination of in vitro and in vivo studies in zebrafish embryos, we show that PAK3(N389) escapes its physiologic degradation and is able to perturb MAPK signaling via an uncontrolled kinase-independent function, which in turn leads to alterations of cerebral and craniofacial structures in vivo. Our data expand the spectrum of phenotypes associated with PAK3 mutations, characterize a novel mechanism resulting in a dual molecular effect of the same mutation with a complex PAK3 functional deregulation and provide evidence for a direct functional impact of aberrant PAK3 function on MAPK signaling.
Assuntos
Proteínas Quinases Ativadas por Mitógeno/metabolismo , Quinases Ativadas por p21/genética , Proteínas ras/metabolismo , Animais , Éxons/genética , Humanos , Cariotipagem , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteínas ras/genéticaRESUMO
Barber-Say syndrome (BSS) and Ablepharon-Macrostomia syndrome (AMS) are congenital malformation syndromes caused by heterozygous mutations in TWIST2. Here we provide a critical review of all patients published with these syndromes. We excluded several earlier reports due to misdiagnosis or insufficient data for reliable confirmation of the diagnosis. There remain 16 reliably diagnosed individuals with BSS and 16 with AMS. Major facial characteristics present in both entities, albeit often in differing frequencies, are excessive facial creases, hypertelorism, underdevelopment of the anterior part of the eyelids (anterior lamella), ectropion, broad nasal ridge and tip, thick and flaring alae nasi, protruding maxilla, wide mouth, thin upper vermillion, and attached ear lobes. In BSS a remarkable extension of the columella on the philtrum can be seen, and in both the medial parts of the cheeks bulge towards the corners of the mouth (cheek pads). Scalp hair is sparse in AMS only, but sparse eyebrows and eyelashes occur in both entities, and general hypertrichosis occurs in BSS. We compare these characteristics with those in Setleis syndrome which can also be caused by TWIST2 mutations. The resemblance between the three syndromes is considerable, and likely differences seem larger than they actually are due to insufficiently complete evaluation for all characteristics of the three entities in the past. It is likely that with time it can be concluded that BSS. AMS and Setleis syndrome form a continuum. © 2016 Wiley Periodicals, Inc.
Assuntos
Anormalidades Múltiplas/diagnóstico , Anormalidades do Olho/diagnóstico , Doenças Palpebrais/diagnóstico , Hirsutismo/diagnóstico , Hipertelorismo/diagnóstico , Hipertricose/diagnóstico , Macrostomia/diagnóstico , Fenótipo , Anormalidades da Pele/diagnóstico , Anormalidades Múltiplas/genética , Anormalidades do Olho/genética , Doenças Palpebrais/genética , Fácies , Estudos de Associação Genética , Genótipo , Hirsutismo/genética , Humanos , Hipertelorismo/genética , Hipertricose/genética , Macrostomia/genética , Mutação , Anormalidades da Pele/genética , Proteína 2 Relacionada a Twist/genéticaRESUMO
Noonan and LEOPARD syndromes are developmental disorders with overlapping features, including cardiac abnormalities, short stature and facial dysmorphia. Increased RAS signaling owing to PTPN11, SOS1 and KRAS mutations causes approximately 60% of Noonan syndrome cases, and PTPN11 mutations cause 90% of LEOPARD syndrome cases. Here, we report that 18 of 231 individuals with Noonan syndrome without known mutations (corresponding to 3% of all affected individuals) and two of six individuals with LEOPARD syndrome without PTPN11 mutations have missense mutations in RAF1, which encodes a serine-threonine kinase that activates MEK1 and MEK2. Most mutations altered a motif flanking Ser259, a residue critical for autoinhibition of RAF1 through 14-3-3 binding. Of 19 subjects with a RAF1 mutation in two hotspots, 18 (or 95%) showed hypertrophic cardiomyopathy (HCM), compared with the 18% prevalence of HCM among individuals with Noonan syndrome in general. Ectopically expressed RAF1 mutants from the two HCM hotspots had increased kinase activity and enhanced ERK activation, whereas non-HCM-associated mutants were kinase impaired. Our findings further implicate increased RAS signaling in pathological cardiomyocyte hypertrophy.
Assuntos
Cardiomiopatia Hipertrófica/genética , Síndrome LEOPARD/genética , Mutação de Sentido Incorreto , Síndrome de Noonan/genética , Proteínas Proto-Oncogênicas c-raf/genética , Animais , Células COS , Cardiomiopatia Hipertrófica/metabolismo , Chlorocebus aethiops , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Síndrome LEOPARD/metabolismo , Síndrome de Noonan/metabolismo , Estrutura Terciária de Proteína , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Proteínas Tirosina Fosfatases/genética , Proteínas Proto-Oncogênicas c-raf/química , Proteínas Proto-Oncogênicas c-raf/metabolismo , Transdução de Sinais , Transfecção , Proteínas ras/metabolismoRESUMO
RASopathies are developmental disorders caused by heterozygous germline mutations in genes encoding proteins in the RAS-MAPK signaling pathway. Reduced growth is a common feature. Several studies generated data on growth, final height (FH), and height velocity (HV) after growth hormone (GH) treatment in patients with these disorders, particularly in Noonan syndrome, the most common RASopathy. These studies, however, refer to heterogeneous cohorts in terms of molecular information, GH status, age at start and length of therapy, and GH dosage. This work reports growth data in 88 patients affected by RASopathies with molecularly confirmed diagnosis, together with statistics on body proportions, pubertal pattern, and FH in 33, including 16 treated with GH therapy for proven GH deficiency. Thirty-three patients showed GH deficiency after pharmacological tests, and were GH-treated for an average period of 6.8 ± 4.8 years. Before starting therapy, HV was -2.6 ± 1.3 SDS, and mean basal IGF1 levels were -2.0 ± 1.1 SDS. Long-term GH therapy, starting early during childhood, resulted in a positive height response compared with untreated patients (1.3 SDS in terms of height-gain), normalizing FH for Ranke standards but not for general population and Target Height. Pubertal timing negatively affected pubertal growth spurt and FH, with IGF1 standardized score increased from -2.43 to -0.27 SDS. During GH treatment, no significant change in bone age velocity, body proportions, or cardiovascular function was observed.
Assuntos
Estatura/efeitos dos fármacos , Crescimento e Desenvolvimento/efeitos dos fármacos , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/uso terapêutico , Puberdade/efeitos dos fármacos , Proteínas ras/deficiência , Criança , Estudos de Coortes , Feminino , Hormônio do Crescimento Humano/farmacologia , Humanos , Recém-Nascido , Masculino , Fatores de Tempo , Resultado do Tratamento , Proteínas ras/metabolismoRESUMO
BACKGROUND: Progressive care improvement for differences of sex development (DSD), regarding diagnosis communication, psychological, medical and surgical management has been claimed. AIM OF THE STUDY: To assess clinical management, quality of life (QoL) and the general psychosocial adjustment of individuals with 46,XY DSD. Some differences related to age at diagnosis are investigated. DESIGN: Cross-sectional study using standardized questionnaires. POPULATION: Forty-three Caucasian females with 46,XY DSD (self declared diagnoses: complete androgen insensitivity syndrome, n = 34; complete gonadal dysgenesis, n = 1; 5α-reductase deficiency, n = 4; Leydig cell hypoplasia, n = 1; unknown diagnosis, n = 3; age years: 31.5 ± 9.6 [range 18-57 years]). SETTING: University Hospitals. METHODS: Subjects were required to fill in questionnaires (ABCL, WHOQOL, dedicated 17-item questionnaire). Academic and socioeconomic data were compared with those of the Italian population. QoL and psychological data were compared with those of a comparison group (46,XX healthy females: n = 43; age, years: 34.5 ± 9.7, range 22-51 years). RESULTS: Present sample of women living with 46,XY DSD were well adapted and were higher achievers than controls, both in educational and professional life. They showed good QoL, but they appeared less satisfied in psychological and social areas. They had borderline mean scores and statistically higher scores than the comparison group for depression, anxiety, internalizing and externalizing problems. Younger persons living with a 46,XY DSD showed better psychosocial adjustment than older ones. Younger women showed lower age at diagnosis communication. Psychological support was more often proposed at the time of diagnosis communication to younger individuals, and they undertook it more frequently than older ones. CONCLUSIONS: Italian people living with 46,XY DSD were well adapted and successful; they reported a good QoL but showed higher degree of psychological distress than the comparison group. Lower psychological distress in younger women could indicate some positive effects of changes in management.