RESUMEN
Congenital heart defect (CHD) is a birth defect that affects the structure of the heart. Although CHD is often multifactorial, it can also be inherited as part of a Mendelian disorder such as in congenital heart defect and ectodermal dysplasia (CHDED). This disorder is caused by de novo variants in PRKD1. Here, we describe a patient with a novel de novo variant of PRKD1 with phenotypic features consistent with CHDED. Previously unreported features were noted including high intracranial pressure (ICP), partial anomalous pulmonary venous return (PAPVR), and bifid uvula. We suggest that these features may be associated with CHDED.
Asunto(s)
Fisura del Paladar , Displasia Ectodérmica , Cardiopatías Congénitas , Humanos , Presión Intracraneal , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/genética , Displasia Ectodérmica/complicaciones , Displasia Ectodérmica/diagnóstico , Displasia Ectodérmica/genética , FenotipoRESUMEN
Peroxisomes are involved in various metabolic reactions. Rhizomelic chondrodysplasia punctata (RCDP) type 1 is one of the peroxisomal biogenesis disorders caused by mutations in the PEX7 gene and is inherited in an autosomal recessive manner. We present a nine-year-old boy with skeletal abnormalities and dysmorphic facial appearance. The patient was born to parents who were first cousins. Very-long-chain fatty acids and pristanic acid levels were in the normal range, but an elevated phytanic acid level was detected by gas chromatography/mass spectrometry. The PEX7 gene was sequenced in the patient and his parents. A novel homozygous mutation, c.192delT (p.F64Lfs*10), was identified in the patient and was present in heterozygosity in both parents. In conclusion, the clinical presentation and peroxisome profile of the patient suggest that this novel mutation leads to RCDP type 1.
Asunto(s)
Condrodisplasia Punctata Rizomélica/genética , Mutación/genética , Receptores Citoplasmáticos y Nucleares/genética , Niño , Condrodisplasia Punctata Rizomélica/metabolismo , Condrodisplasia Punctata Rizomélica/patología , Femenino , Cromatografía de Gases y Espectrometría de Masas , Heterocigoto , Homocigoto , Humanos , Masculino , Linaje , Receptor de la Señal 2 de Direccionamiento al Peroxisoma , Ácido Fitánico/metabolismo , Reacción en Cadena de la PolimerasaRESUMEN
Individuals harboring germ-line DICER1 mutations are predisposed to a rare cancer syndrome, the DICER1 Syndrome or pleuropulmonary blastoma-familial tumor and dysplasia syndrome [online Mendelian inheritance in man (OMIM) #601200]. In addition, specific somatic mutations in the DICER1 RNase III catalytic domain have been identified in several DICER1-associated tumor types. Pituitary blastoma (PitB) was identified as a distinct entity in 2008, and is a very rare, potentially lethal early childhood tumor of the pituitary gland. Since the discovery by our team of an inherited mutation in DICER1 in a child with PitB in 2011, we have identified 12 additional PitB cases. We aimed to determine the contribution of germ-line and somatic DICER1 mutations to PitB. We hypothesized that PitB is a pathognomonic feature of a germ-line DICER1 mutation and that each PitB will harbor a second somatic mutation in DICER1. Lymphocyte or saliva DNA samples ascertained from ten infants with PitB were screened and nine were found to harbor a heterozygous germ-line DICER1 mutation. We identified additional DICER1 mutations in nine of ten tested PitB tumor samples, eight of which were confirmed to be somatic in origin. Seven of these mutations occurred within the RNase IIIb catalytic domain, a domain essential to the generation of 5p miRNAs from the 5' arm of miRNA-precursors. Germ-line DICER1 mutations are a major contributor to PitB. Second somatic DICER1 "hits" occurring within the RNase IIIb domain also appear to be critical in PitB pathogenesis.
Asunto(s)
ARN Helicasas DEAD-box/genética , Mutación , Neoplasias Complejas y Mixtas/genética , Neoplasias Complejas y Mixtas/patología , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/patología , Ribonucleasa III/genética , Preescolar , Análisis Mutacional de ADN , Resultado Fatal , Mutación de Línea Germinal , Humanos , Inmunohistoquímica , Lactante , Imagen por Resonancia Magnética , Neoplasias Complejas y Mixtas/cirugía , Linaje , Neoplasias Hipofisarias/cirugía , Radiografía Torácica , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is the most common undifferentiated ovarian malignancy in women under 40 years of age. We sequenced the exomes of six individuals from three families with SCCOHT. After discovering segregating deleterious germline mutations in SMARCA4 in all three families, we tested DNA from a fourth affected family, which also carried a segregating SMARCA4 germline mutation. All the familial tumors sequenced harbored either a somatic mutation or loss of the wild-type allele. Immunohistochemical analysis of these cases and additional familial and non-familial cases showed loss of SMARCA4 (BRG1) protein in 38 of 40 tumors overall. Sequencing of cases with available DNA identified at least one germline or somatic deleterious SMARCA4 mutation in 30 of 32 cases. Additionally, the SCCOHT cell line BIN-67 had biallelic deleterious mutations in SMARCA4. Our findings identify alterations in SMARCA4 as the major cause of SCCOHT, which could lead to improvements in genetic counseling and new treatment approaches.
Asunto(s)
Carcinoma de Células Pequeñas/genética , ADN Helicasas/genética , Mutación/genética , Proteínas Nucleares/genética , Neoplasias Ováricas/genética , Factores de Transcripción/genética , Secuencia de Bases , Línea Celular Tumoral , Exoma/genética , Femenino , Componentes del Gen , Humanos , Immunoblotting , Inmunohistoquímica , Hibridación Fluorescente in Situ , Datos de Secuencia Molecular , Análisis de Secuencia de ADNRESUMEN
DICER1 is an endoribonuclease responsible for the production of mature microRNAs which are small, single-stranded RNA molecules that regulate gene expression post-transcriptionally by binding to mRNA and repressing the expression of target genes. Germ-line mutations in DICER1 are responsible for a rare cancer syndrome, including tumors that can co-occur with multinodular goiter (MNG). Using Sanger sequencing, we screened all DICER1 exons and intron boundaries in 20 suspected mutation carriers: nine with ovarian sex cord-stromal tumors (including Sertoli-Leydig cell tumors (SLCTs)), five with pleuropulmonary blastoma, one with cystic nephroma, one with nasal chondromesenchymal hamartoma and four with more than one manifestation suggestive of a germ-line DICER1 mutation. All were negative for any apparently deleterious variants. We developed a Multiplex Ligation-based Probe Amplification assay for DICER1 to screen for large deletions or duplications. Synthetic oligonucleotides were designed to cover all exons in three probe-mixes. In a child with a SLCT and MNG, and in her mother and brother (both diagnosed with MNG), we identified a heterozygous germ-line deletion of approximately 3 kilobases that eliminates exon 21 of DICER1 and two-thirds of intron 21, accompanied by an insertion of a G nucleotide at the 3' end of the deletion (c.3270-6_4051-1280delinsG). This allele is expressed in the patient's cDNA, creating an out-of-frame deletion predicted to result in a truncated protein (r.3270_4050del; p.Tyr1091Ser*28). Our novel finding of a disease-causing large deletion in DICER1 emphasizes the need to include assays that can detect rearrangements, duplications and deletions in any DICER1 screening protocol.
Asunto(s)
ARN Helicasas DEAD-box/genética , Células Germinativas/química , Reacción en Cadena de la Polimerasa Multiplex/métodos , Oligonucleótidos/química , Ribonucleasa III/genética , Eliminación de Secuencia , Alelos , Niño , Exones , Femenino , Mutación del Sistema de Lectura , Reordenamiento Génico , Mutación de Línea Germinal , Bocio Nodular/complicaciones , Bocio Nodular/genética , Humanos , Intrones , Masculino , Neoplasias Ováricas/complicaciones , Neoplasias Ováricas/genética , Linaje , Análisis de Secuencia de ADNRESUMEN
Organogels can be prepared by immobilizing an organic phase into a three-dimensional network coming from the self-assembly of a low molecular weight gelator molecule. In this work, an injectable subcutaneous organogel system based on safflower oil and a modified-tyrosine organogelator was evaluated in vivo for the delivery of rivastigmine, an acetylcholinesterase (AChE) inhibitor used in the treatment of Alzheimer's disease. Different implant formulations were injected and the plasmatic drug concentration was assayed for up to 35 days. In parallel, the inhibition of AChE in different brain sections and the biocompatibility of the implants were monitored. The pharmacokinetic profiles were found to be influenced by the gel composition, injected dose and volume of the implant. The sustained delivery of rivastigmine was accompanied by a significant prolonged inhibition of AChE in the hippocampus, a brain structure involved in memory. The implant induced only a minimal to mild chronic inflammation and fibrosis, which was comparable to poly(D,L-lactide-co-glycolide) in situ-forming implants. These findings suggest that tyrosine-based organogels could represent an alternative approach to current formulations for the sustained delivery of cholinesterase inhibitors.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Fenilcarbamatos/uso terapéutico , Tirosina/química , Inhibidores de la Colinesterasa/administración & dosificación , Inhibidores de la Colinesterasa/química , Cromatografía Liquida , Geles , Humanos , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/química , Fenilcarbamatos/administración & dosificación , Fenilcarbamatos/química , Rivastigmina , Espectrometría de Masas en TándemRESUMEN
The recent advent of biotechnologies has led to the development of labile macromolecular therapeutic agents that require complex formulations for their efficient administration. This work reports a novel concept for the systemic, sustained delivery of such agents. The proposed approach is based on the spontaneous self-assembly of low-molecular weight amphiphilic amino acid derivatives in a hydrophobic pharmaceutical vehicle. The injectable, in situ-forming organogels were obtained by mixing N-stearoyl l-alanine (m)ethyl esters with a vegetable oil and a biocompatible hydrophilic solvent. The gels' in vivo-delivering properties were evaluated in rats with leuprolide, a luteinizing hormone-releasing hormone agonist used in prostate cancer, endometriosis and precocious puberty treatment. Following subcutaneous injection, the gels degraded and gradually released leuprolide for 14 to 25 days. Drug release was accompanied by sustained castration lasting up to 50 days, as assessed by testosterone levels. This study demonstrates that in situ-forming implants based on l-alanine derivatives represent a novel injectable platform for the controlled delivery of hydrophilic compounds, which is simpler than currently available implant and microsphere technologies.