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2.
Mol Cell ; 80(4): 648-665.e9, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33176162

RESUMO

The RNA isoform repertoire is regulated by splicing factor (SF) expression, and alterations in SF levels are associated with disease. SFs contain ultraconserved poison exon (PE) sequences that exhibit greater identity across species than nearby coding exons, but their physiological role and molecular regulation is incompletely understood. We show that PEs in serine-arginine-rich (SR) proteins, a family of 14 essential SFs, are differentially spliced during induced pluripotent stem cell (iPSC) differentiation and in tumors versus normal tissues. We uncover an extensive cross-regulatory network of SR proteins controlling their expression via alternative splicing coupled to nonsense-mediated decay. We define sequences that regulate PE inclusion and protein expression of the oncogenic SF TRA2ß using an RNA-targeting CRISPR screen. We demonstrate location dependency of RS domain activity on regulation of TRA2ß-PE using CRISPR artificial SFs. Finally, we develop splice-switching antisense oligonucleotides to reverse the increased skipping of TRA2ß-PE detected in breast tumors, altering breast cancer cell viability, proliferation, and migration.


Assuntos
Neoplasias da Mama/patologia , Diferenciação Celular , Éxons , Síndromes Mielodisplásicas/patologia , Proteínas do Tecido Nervoso/metabolismo , Splicing de RNA , Fatores de Processamento de Serina-Arginina/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Humanos , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Proteínas do Tecido Nervoso/genética , Isoformas de Proteínas , Fatores de Processamento de Serina-Arginina/genética , Células Tumorais Cultivadas
3.
PLoS Genet ; 17(4): e1009512, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33872315

RESUMO

The actin cytoskeleton is a well-known player in most vital cellular processes, but comparably little is understood about how the actin assembly machinery impacts programmed cell death pathways. In the current study, we explored roles for the human Wiskott-Aldrich Syndrome Protein (WASP) family of actin nucleation factors in DNA damage-induced apoptosis. Inactivation of each WASP-family gene revealed that two of them, JMY and WHAMM, are necessary for rapid apoptotic responses. JMY and WHAMM participate in a p53-dependent cell death pathway by enhancing mitochondrial permeabilization, initiator caspase cleavage, and executioner caspase activation. JMY-mediated apoptosis requires actin nucleation via the Arp2/3 complex, and actin filaments are assembled in cytoplasmic territories containing clusters of cytochrome c and active caspase-3. The loss of JMY additionally results in significant changes in gene expression, including upregulation of the WHAMM-interacting G-protein RhoD. Depletion or deletion of RHOD increases cell death, suggesting that RhoD normally contributes to cell survival. These results give rise to a model in which JMY and WHAMM promote intrinsic cell death responses that can be opposed by RhoD.


Assuntos
Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/genética , Proteínas Nucleares/genética , Transativadores/genética , Proteína Supressora de Tumor p53/genética , Síndrome de Wiskott-Aldrich/genética , Proteínas rho de Ligação ao GTP/genética , Citoesqueleto de Actina/genética , Proteína 2 Relacionada a Actina/genética , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Proteína 3 Relacionada a Actina/genética , Apoptose/genética , Citocromos c/genética , Dano ao DNA/genética , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , RNA Interferente Pequeno/genética , Proteína da Síndrome de Wiskott-Aldrich/genética
4.
Neurosurg Focus ; 57(2): E10, 2024 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088865

RESUMO

OBJECTIVE: The pediatric neurosurgical community has increasingly recognized the importance of healthcare transition, the process of moving a patient from a pediatric to an adult model of care. However, surveys of pediatric neurosurgeons have revealed that few institutions have formal transition programs. Here, the authors share their preliminary experience with the development of a formal transition pilot program for patients with spina bifida and/or hydrocephalus. METHODS: Patients 18 years of age or older with a diagnosis of spina bifida and/or hydrocephalus who were followed by a pediatric neurosurgeon at Connecticut Children's from January 2017 to December 2023 and were recommended to transition to an adult neurosurgeon were retrospectively reviewed. Patients in the informal transition program (ITP) cohort (i.e., the recommendation to transition was made before the formal transition program [FTP] was developed in early 2020) were compared with those in the FTP cohort. RESULTS: Twenty-two patients met inclusion criteria with 7 (31.8%) in the ITP cohort and 15 (68.2%) in the FTP cohort. The median age at the time of the recommendation to transition was similar in both ITP and FTP cohorts (24 [IQR 20-35] years vs 25 [IQR 24-27] years, respectively). Four (57.1%) patients in the ITP cohort had a confirmed visit with an adult neurosurgeon, compared with 13 (86.7%) patients in the FTP cohort (p = 0.274). One patient in the ITP cohort with a failed transition returned to pediatric neurosurgical care, and 1 patient in the FTP cohort required a shunt revision by an adult neurosurgeon within 1 year of the recommendation to transition. CONCLUSIONS: Healthcare transition is recognized as a priority within pediatric neurosurgery, but structured, formal transition programs remain underdeveloped. The authors' preliminary experience with a pilot transition program demonstrated that patients who underwent a formal transition were more likely to successfully establish care with an adult neurosurgeon and trended toward less resource utilization.


Assuntos
Hidrocefalia , Disrafismo Espinal , Humanos , Disrafismo Espinal/cirurgia , Disrafismo Espinal/complicações , Hidrocefalia/cirurgia , Projetos Piloto , Masculino , Feminino , Estudos Retrospectivos , Adulto Jovem , Adolescente , Adulto , Transição para Assistência do Adulto/tendências , Neurocirurgia/métodos , Procedimentos Neurocirúrgicos/métodos , Criança , Neurocirurgiões
5.
Neurosurg Focus ; 54(6): E9, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37283444

RESUMO

OBJECTIVE: Sagittal craniosynostosis is the most common form of craniosynostosis and typically results in scaphocephaly, which is characterized by biparietal narrowing, compensatory frontal bossing, and an occipital prominence. The cephalic index (CI) is a simple metric for quantifying the degree of cranial narrowing and is often used to diagnose sagittal craniosynostosis. However, patients with variant forms of sagittal craniosynostosis may present with a "normal" CI, depending on the part of the suture that is closed. As machine learning (ML) algorithms are developed to assist in the diagnosis of cranial deformities, metrics that reflect the other phenotypic features of sagittal craniosynostosis are needed. In this study the authors sought to describe the posterior arc angle (PAA), a measurement of biparietal narrowing that is obtained with 2D photographs, and elucidate the role of PAA as an adjuvant to the CI in characterizing scaphocephaly and the potential relevance of PAA in new ML model development. METHODS: The authors retrospectively reviewed 1013 craniofacial patients treated during the period from 2006 to 2021. Orthogonal top-down photographs were used to calculate the CI and PAA. Distribution densities, receiver operating characteristic (ROC) curves, and chi-square analyses were used to describe the relative predictive utility of each method for sagittal craniosynostosis. RESULTS: In total, 1001 patients underwent paired CI and PAA measurements and a clinical head shape diagnosis (sagittal craniosynostosis, n = 122; other cranial deformity, n = 565; normocephalic, n = 314). The area under the ROC curve (AUC) for the CI was 98.5% (95% confidence interval 97.8%-99.2%, p < 0.001), with an optimum specificity of 92.6% and sensitivity of 93.4%. The PAA had an AUC of 97.4% (95% confidence interval 96.0%-98.8%, p < 0.001) with an optimum specificity of 94.9% and sensitivity of 90.2%. In 6 of 122 (4.9%) cases of sagittal craniosynostosis, the PAA was abnormal while the CI was normal. This means that adding a PAA cutoff branch to a partition model increases the detection of sagittal craniosynostosis. CONCLUSIONS: Both CI and PAA are excellent discriminators for sagittal craniosynostosis. Using an accuracy-optimized partition model, the addition of the PAA to the CI increased model sensitivity compared to using the CI alone. Using a model that incorporates both CI and PAA could assist in the early identification and treatment of sagittal craniosynostosis via automated and semiautomated algorithms that utilize tree-based ML models.


Assuntos
Craniossinostoses , Humanos , Lactente , Estudos Retrospectivos , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/cirurgia , Crânio/cirurgia , Procedimentos Neurocirúrgicos , Algoritmos
6.
Neurosurg Focus ; 55(4): E8, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37778041

RESUMO

OBJECTIVE: Septic cerebral venous sinus thrombosis (CVST) is a recognized complication of pediatric sinogenic and otogenic intracranial infections. The optimal treatment paradigm remains controversial. Proponents of anticoagulation highlight its role in preventing thrombus propagation and promoting recanalization, while others cite the risk of hemorrhagic complications, especially after a neurosurgical procedure for an epidural abscess or subdural empyema. Here, the authors investigated the diagnosis, management, and outcomes of pediatric patients with sinogenic or otogenic intracranial infections and a septic CVST. METHODS: All patients 21 years of age or younger, who presented with an intracranial infection in the setting of sinusitis or otitis media and who underwent neurosurgical treatment at Connecticut Children's, Rady Children's Hospital-San Diego, or Ann and Robert H. Lurie Children's Hospital of Chicago from March 2015 to March 2023, were retrospectively reviewed. Demographic, clinical, and radiological data were systematically collated. RESULTS: Ninety-six patients were treated for sinusitis-related and/or otitis media-related intracranial infections during the study period, 15 (15.6%) of whom were diagnosed with a CVST. Of the 60 patients who presented prior to the COVID-19 pandemic, 6 (10.0%) were diagnosed with a septic CVST, whereas of the 36 who presented during the COVID-19 pandemic, 9 (25.0%) had a septic CVST (p = 0.050). The superior sagittal sinus was involved in 12 (80.0%) patients and the transverse and/or sigmoid sinuses in 4 (26.7%). Only 1 (6.7%) patient had a fully occlusive thrombus. Of the 15 patients with a septic CVST, 11 (73.3%) were initiated on anticoagulation at a median interval of 4 (IQR 3-5) days from the most recent neurosurgical procedure. Five (45.5%) patients who underwent anticoagulation demonstrated complete recanalization on follow-up imaging, and 4 (36.4%) had partial recanalization. Three (75.0%) patients who did not undergo anticoagulation demonstrated complete recanalization, and 1 (25.0%) had partial recanalization. None of the patients treated with anticoagulation experienced hemorrhagic complications. CONCLUSIONS: Septic CVST is frequently identified among pediatric patients undergoing neurosurgical intervention for sinogenic and/or otogenic intracranial infections and may have become more prevalent during the COVID-19 pandemic. Anticoagulation can be used safely in the acute postoperative period if administered cautiously, in a monitored setting, and with interval cross-sectional imaging. However, some patients exhibit excellent outcomes without anticoagulation, and further studies are needed to identify those who may benefit the most from anticoagulation.


Assuntos
COVID-19 , Otite Média , Trombose dos Seios Intracranianos , Humanos , Criança , Estudos Retrospectivos , Pandemias , COVID-19/complicações , Otite Média/complicações , Otite Média/tratamento farmacológico , Otite Média/cirurgia , Anticoagulantes/uso terapêutico , Trombose dos Seios Intracranianos/diagnóstico por imagem , Trombose dos Seios Intracranianos/tratamento farmacológico , Trombose dos Seios Intracranianos/cirurgia
7.
Acta Neurochir (Wien) ; 165(5): 1323-1331, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36920663

RESUMO

BACKGROUND: Meningiomas are the most common intracranial tumors. Recent advancements in the genetic profiling of tumors have allowed information including DNA copy number analysis, mutational analysis, and RNA sequencing to be more frequently reported, in turn allowing better characterization of meningiomas. In recent years, analysis of tumor methylomes that reflects both cell-origin methylation signatures and somatically acquired DNA methylation changes has been utilized to better classify meningiomas with great success. METHOD: We report DNA methylation profiling on meningiomas from 17 patients. Formalin-fixed paraffin-embedded (FFPE) meningioma tumor samples were processed, loaded onto the Infinium Methylation EPIC array, and scanned using the Illumina IScan system. Raw IDAT files were processed through the the CNS tumor classifier developed by the Molecular Neuropathology group at the German Cancer Research Center (DKFZ). Corresponding genomics were captured using targeted sequencing panels. RESULT: Among the meningioma samples, 13 samples were classified as "benign," two samples as "intermediate," and the remaining three samples (from two patients) as "malignant," based on previously validated classification algorithms. In addition to tumor methylation profiling, we also present information that includes patient demographics, clinical presentations, tumor characteristics (including size and location), surgical approaches, and mutational analysis. The two patients who provided the samples with "malignant" methylation classifications had tumor recurrence, reflecting a more aggressive disease course. CONCLUSION: In accordance with prior reports, our case series provides support that tumor DNA methylation profiling adds meaningful classification information and may be beneficial to incorporate in clinical practice. Our report also reveals that DNA methylation combined with WHO histology classification can more accurately predict tumor behavior than WHO classification alone.


Assuntos
Neoplasias do Sistema Nervoso Central , Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/diagnóstico , Meningioma/genética , Metilação de DNA/genética , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/genética , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/genética
8.
Neurosurg Focus ; 52(6): E11, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35921182

RESUMO

OBJECTIVE: Telemedicine can be an effective tool for the evaluation of the pediatric patient with a cranial deformity, but it increases the reliance of neurosurgical providers on data provided by patients and families. Family-acquired photographs, in particular, can be used to augment the evaluation of pediatric head shape abnormalities via telemedicine, but photographs of sufficient quality are necessary. Here, the authors systematically reviewed the quality and utility of family-acquired photographs for patients referred to their pediatric neurosurgery clinic for telemedicine-based head shape evaluations. METHODS: All telemedicine encounters that were completed for head shape abnormalities at the authors' institution between May 2020 and December 2021 were retrospectively reviewed. Instructions were sent to families prior to each visit with examples of ideal photographs. Three orthogonal views of the patient's head-frontal, lateral, and vertex-were requested. Data were collected regarding demographics, diagnosis, follow-up, and photograph quality. Quality variables included orthogonality of each requested view, appropriate distance, appropriate lighting, presence of distracting elements, and whether hair obscured the head shape. RESULTS: Overall, 565 patients had 892 visits during the study period. A total of 1846 photograph requests were made, and 3335 photographs were received for 829 visits. Of 2676 requested orthogonal views, 1875 (70%) were received. Of these, 1826 (97%) had adequate lighting, 1801 (96%) had appropriate distance, and 1826 (97%) had no distracting features. Hair did not obscure the head shape on the vertex view in 557 visits with orthogonal vertex views (82%). In-person follow-up was requested for further medical evaluation in 40 visits (5%). CONCLUSIONS: The family-acquired photographs in this series demonstrated high rates of adequate lighting and distance, without distracting features. Lack of orthogonality and obscuration of the head shape by hair, however, were more common issues. Family education prior to the visit may improve the quality of family-acquired photographs but requires an investment of time by medical staff. Efforts to further improve photographic quality will facilitate efforts to perform craniometric evaluations through telemedicine visits.


Assuntos
Telemedicina , Criança , Humanos , Procedimentos Neurocirúrgicos , Fotografação , Estudos Retrospectivos
9.
Neurosurg Focus ; 53(6): E15, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36455272

RESUMO

OBJECTIVE: Pediatric low-grade gliomas (pLGGs) frequently exhibit dysregulation of the mitogen-activated protein kinase (MAPK) pathway. Targeted therapies, including mutant BRAF inhibitors (dabrafenib) and MEK inhibitors (trametinib), have shown promise in patients in whom conventional chemotherapy has failed. However, few studies have investigated the use of targeted therapy as a first-line treatment for pLGG. Here, the authors reviewed their institutional experience with using a personalized medicine approach to patients with newly diagnosed pLGGs. METHODS: All pediatric patients at the authors' institution who had been treated with dabrafenib or trametinib for pLGG without first receiving conventional chemotherapy or radiation were retrospectively reviewed. Demographic, clinical, and radiological data were collected. RESULTS: Eight patients underwent targeted therapy as a first-line treatment for pLGG. Five patients had a BRAF alteration (1 with a BRAFV600E mutation, 4 with a KIAA1549:BRAF fusion), and 3 patients had an NF1 mutation. One of the 8 patients was initially treated with dabrafenib, and trametinib was added later. Seven patients were initially treated with trametinib; of these, 2 later transitioned to dual therapy, whereas 5 continued with trametinib monotherapy. Six patients (75%) demonstrated a partial response to therapy during their treatment course, whereas stable disease was identified in the remaining 2 patients (25%). One patient experienced mild disease progression after completing a course of trametinib monotherapy, but ultimately stabilized after a period of close observation. Another patient experienced tumor progression while on dabrafenib, but subsequently responded to dual therapy with dabrafenib and trametinib. The most common adverse reactions to targeted therapy were cutaneous toxicity (100%) and diarrhea (50%). CONCLUSIONS: Targeted therapies have the potential to become a standard treatment option for pLGG due to their favorable toxicity profile and oral route of administration. This case series provides preliminary evidence that targeted therapies can induce an early disease response as a first-line adjuvant treatment; however, large-scale studies are required to assess long-term durability and safety.


Assuntos
Glioma , Proteínas Proto-Oncogênicas B-raf , Criança , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , Estudos Retrospectivos , Oximas/uso terapêutico , Adjuvantes Imunológicos , Glioma/tratamento farmacológico , Glioma/genética , Inibidores de Proteínas Quinases/uso terapêutico
10.
Acta Neurochir (Wien) ; 164(9): 2491-2503, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35881312

RESUMO

BACKGROUND: Meningiomas are the most common primary central nervous system tumor. Previous studies have characterized recurrent genetic alterations that can predict patient prognosis and potentially provide new avenues for therapeutic intervention. Continued efforts to characterize the genomic changes in meningioma samples can aid in the discovery of therapeutic targets and appropriate patient stratification. METHODS: We performed targeted genomic sequencing on 25 primary and 2 recurrent meningiomas using a 500-gene panel, including canonical meningioma drivers. We further detail the genomic profiles and relevant clinical findings in three cases of angiomatous meningiomas and two recurrent atypical meningiomas. RESULTS: Our approach uncovers a diverse landscape of genomic variants in meningioma samples including mutations in established meningioma-related genes NF2, AKT1, PIK3CA, and TRAF7. In addition to known meningioma drivers, we uncover variants in genes encoding other PI3K subunits, Notch/hedgehog/Wnt signaling pathway components, and chromatin regulators. We additionally identify 22 genes mutated across multiple samples. Three patients included in the study were diagnosed with angiomatous WHO grade I meningiomas, all three of which contained variants in the PI3K-AKT signaling pathway previously described to regulate tumor angiogenesis. Analysis of patient-matched primary and recurrent atypical meningiomas revealed clonal enrichment for mutations in the SWI/SNF complex subunits ARID1A and SMARCA4. CONCLUSIONS: Targeted genomics implemented in neuro-oncology care can enhance our understanding of the genetic underpinnings of central nervous system tumors, including meningiomas. These molecular signatures may be clinically useful in dictating treatment strategies and patient follow-up.


Assuntos
Neoplasias Meníngeas , Meningioma , DNA Helicases , Genômica , Humanos , Neoplasias Meníngeas/patologia , Meningioma/patologia , Recidiva Local de Neoplasia , Proteínas Nucleares , Fosfatidilinositol 3-Quinases/genética , Fatores de Transcrição
11.
Br J Neurosurg ; : 1-5, 2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-35001774

RESUMO

Pregnancy-associated meningiomas have unique considerations and features regarding their pathophysiology, location, genetic profile, and neurosurgical management. These tumours have been reported to undergo rapid growth during gestation and regression post-partum, implicating a role for female sex hormones in tumour physiology. In addition, these tumours occur at a higher incidence in the skull base compared to sporadic meningiomas in the general population, often impinging neurovascular structures and requiring emergent resection. While the genomics of sporadic meningiomas have been described, there are no reports characterizing the genetic features of those associated with pregnancy. Here we describe a patient diagnosed with a diphragma sellae meningioma early in the third trimester after presenting with rapidly deteriorating vision. At 32 weeks gestation the baby was delivered by caesarean section and the tumour subsequently removed. Genomic profiling of the tumour sample revealed variants of unknown significant (VUS) in six genes, none of which were in canonical meningioma drivers. We describe our surgical approach and discuss the relevant pathology and genomics, as well as medical and surgical management considerations of meningiomas in pregnancy.

13.
J Neurosurg Case Lessons ; 8(8)2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39159494

RESUMO

BACKGROUND: Dorsal thoracic arachnoid web is a rare diagnosis and is not commonly seen in neurosurgical practice. Patients can present with symptoms and signs of thoracic myelopathy in the setting of an arachnoid cyst and a presyrinx state. OBSERVATIONS: A 57-year-old male with a 10-year history of worsening bilateral leg weakness and chronic back pain re-presented to the neurosurgery clinic after being seen by neurology and orthopedic spine surgery. Initial imaging was concerning for myelomalacia and syringomyelia, and repeat delayed computed tomography myelography findings were consistent with an evolving thoracic arachnoid web, now demonstrating spinal cord compression secondary to arachnoid cyst formation and consistent with the signs of thoracic myelopathy. Intraoperative ultrasound displayed the arachnoid web as the cause of the evolving arachnoid cyst, edematous spinal cord, and a presyrinx-like state. The patient underwent surgical decompression, which restored cerebrospinal fluid (CSF) dynamics, resulting in clinical improvement. LESSONS: Dorsal thoracic arachnoid web is a dynamic condition that can occur in the setting of an arachnoid cyst. There appears to be a relationship between dorsal thoracic arachnoid web formation and the presence of an arachnoid cyst resulting from a ball-valve mechanism leading to the creation of a pressure gradient effect that alters CSF fluid dynamics. https://thejns.org/doi/10.3171/CASE24313.

14.
Neuro Oncol ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39093629

RESUMO

BACKGROUND: Advances in our understanding of the molecular biology of meningiomas have led to significant gains in the ability to predict patient prognosis and tumor recurrence and to identify novel targets for therapeutic design. Specifically, classification of meningiomas based on DNA methylation has greatly improved our ability to risk stratify patients, however new questions have arisen in terms of the underlying impact these DNA methylation signatures have on meningioma biology. METHODS: This study utilizes RNA-seq data from 486 meningioma samples corresponding to three meningioma DNA methylation groups (Merlin-intact, Immune-enriched, and Hypermitotic), followed by in vitro experiments utilizing human meningioma cell lines. RESULTS: We identify alterations in RNA splicing between meningioma DNA methylation groups including individual splicing events that correlate with Hypermitotic meningiomas and predict tumor recurrence and overall patient prognosis and compile a set of splicing events that can accurately predict DNA methylation classification based on RNA-seq data. Furthermore, we validate these events using RT-PCR in patient samples and meningioma cell lines. Additionally, we identify alterations in RNA binding proteins and splicing factors that lie upstream of RNA splicing events, including upregulation of SRSF1 in Hypermitotic meningiomas which we show drives alternative RNA splicing changes. Finally, we design splice switching antisense oligonucleotides to target RNA splicing changes in NASP and MFF observed in Hypermitotic meningiomas, providing a rationale for RNA-based therapeutic design. CONCLUSIONS: RNA splicing is an important driver of meningioma phenotypes that can be useful in prognosticating patients and as a potential exploit for therapeutic vulnerabilities.

15.
Science ; 385(6714): eadj1979, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39265028

RESUMO

T cell receptor (TCR) sensitivity to peptide-major histocompatibility complex (MHC) dictates T cell fate. Canonical models of TCR sensitivity cannot be fully explained by transcriptional regulation. In this work, we identify a posttranscriptional regulatory mechanism of TCR sensitivity that guides alternative splicing of TCR signaling transcripts through an evolutionarily ultraconserved poison exon (PE) in the RNA-binding protein (RBP) TRA2ß in mouse and human. TRA2ß-PE splicing, seen during cancer and infection, was required for TCR-induced effector T cell expansion and function. Tra2ß-PE skipping enhanced T cell response to antigen by increasing TCR sensitivity. As antigen levels decreased, Tra2ß-PE reinclusion allowed T cell survival. Finally, we found that TRA2ß-PE was first included in the genome of jawed vertebrates that were capable of TCR gene rearrangements. We propose that TRA2ß-PE splicing acts as a gatekeeper of TCR sensitivity to shape T cell fate.


Assuntos
Processamento Alternativo , Éxons , Receptores de Antígenos de Linfócitos T , Fatores de Processamento de Serina-Arginina , Animais , Humanos , Camundongos , Sobrevivência Celular , Sequência Conservada , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Fatores de Processamento de Serina-Arginina/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo
16.
J Neurosurg Pediatr ; 32(4): 472-477, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37548529

RESUMO

OBJECTIVE: Ridging along the metopic suture line can be a common cause of concern for parents and has been theorized to represent a mild form of trigonocephaly, a cranial deformity associated with risks of negative cosmetic outcomes, if not surgically corrected. Yet the literature contains sparse reports of long-term cosmetic results or expectations for infants with isolated metopic ridging compared with those with severe trigonocephaly, or even what objective metrics discriminate isolated metopic ridging from severe trigonocephaly. Therefore, the authors' goals for this study were to 1) quantify the degree of frontal deformity among patients with metopic ridge, metopic craniosynostosis, and normocephalic head shapes; and 2) document the natural history of frontal deformities in isolated metopic ridge patients in the 1st year of life. METHODS: This was a retrospective cohort study of patients with normocephalic head shapes, metopic ridges, and metopic craniosynostoses who presented at < 1 year of age to the Connecticut Children's neurosurgery clinic from January 2019 to December 2021. Data were collected regarding demographics and photograph-based craniometrics. RESULTS: A total of 212 normocephalic, 34 metopic ridge, and 29 metopic craniosynostosis patients were included. Both the normocephalic and metopic ridge groups had a significantly higher anterior arc angle (AAA) value compared with the metopic craniosynostosis group (p < 0.0001). The AAA did not differ significantly among normocephalic patients and those with ridging. Over the course of 1 year of follow-up, patients with metopic ridging demonstrated a slight decrease in AAA values, but overall remained within the same range as normocephalic patients. CONCLUSIONS: Photograph-based craniometrics suggest that metopic ridge patients with frontal bone angulations > 2.2 radians have a mild degree of frontal constriction that does not significantly worsen over the 1st year of life.


Assuntos
Craniossinostoses , Lactente , Criança , Humanos , Estudos Retrospectivos , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/cirurgia , Craniossinostoses/complicações , Suturas Cranianas/cirurgia , Cefalometria/métodos
17.
J Neurosurg Pediatr ; 32(1): 82-90, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37029682

RESUMO

OBJECTIVE: Quantitative measurements of trigonocephaly can be used to characterize and track this phenotype, which is associated with metopic craniosynostosis. Traditionally, trigonocephaly metrics were extracted from CT scans; however, this method exposes patients to ionizing radiation. Three-dimensional optical scans are another option but are not routinely available in most outpatient settings. Recently, the authors developed semiautomated artificial intelligence algorithms that extract craniometric data from orthogonal 2D photographs. Although 2D photographs are safe, inexpensive, and straightforward to obtain, the accuracy of photograph-based craniometrics in comparison to CT and 3D optical scan correlates has not been established. In this study the authors compared the classification power of 2D photograph-based metrics of trigonocephaly with four CT-based metrics and one 3D optical scan-based metric in a heterogeneous series of patients who presented to an outpatient craniofacial clinic. METHODS: In this study the authors performed retrospective craniometric analyses of patient 2D photographs, 3D optical scans, and CT scans. Imaging-derived craniometrics include the 2D photograph-based anterior arc angle (AAA2D-photo), anterior-posterior ratio (APR2D-photo), and anterior-middle ratio (AMR2D-photo); the CT-based anterior arc angle (AAACT), metopic index (MICT), endocranial-bifrontal angle (eBFACT), and interfrontal angle (IFACT); and the 3D optical scan-based anterior arc angle (AAA3D-optical). Receiver operating characteristics (ROCs) were used to identify craniometrics strongly descriptive of trigonocephaly. Interrater comparisons were made between paired trigonocephaly measurements obtained from photographs and either CT scans or 3D optical scans. RESULTS: There were 13 photograph-based and CT-based pairs and 22 paired measurements from 2D photographs and 3D optical scans. AAA displayed the strongest classification capacity across all three imaging modalities. Significant agreement was observed between AAACT and AAA2D-photo (intraclass correlation coefficient [ICC] = 0.68 [95% CI 0.24-0.89], p = 0.0035), and AAA3D-optical and AAA2D-photo (ICC = 0.70 [95% CI 0.41-0.87], p < 0.0001). There was no significant correlation between APR2D-photo or AMR2D-photo and conventional CT-based metrics describing longitudinal width ratios (MICT). CONCLUSIONS: Photograph-based craniometrics are powerful tools that can be used to quantify the severity of trigonocephaly and exhibit high concordance with standard measurements derived from CT scans and 3D optical scans. The authors developed and freely share a research-use application to calculate trigonocephaly metrics from 2D photographs. Given the availability of digital photography, lack of ionizing radiation, and low cost of photograph-based craniometric derivation, this technique may be useful to supplement routine ambulatory care and objectively track outcomes following treatment.


Assuntos
Inteligência Artificial , Craniossinostoses , Humanos , Estudos Retrospectivos , Benchmarking , Craniossinostoses/diagnóstico por imagem , Cefalometria/métodos , Imageamento Tridimensional/métodos
18.
J Neurosurg Case Lessons ; 6(23)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38048560

RESUMO

BACKGROUND: Esthesioneuroblastoma (ENB) is a rare neoplasm of the sinonasal tract. Currently, the optimal treatment includes maximal resection combined with radiotherapy and/or chemotherapy. Although ENBs often recur and have an aggressive clinical course, spinal metastases are extremely rare and the underlying molecular mechanisms are poorly understood. OBSERVATIONS: Here, the authors describe a 50-year-old male with an aggressive ENB, initially treated with resection and chemotherapy/radiation, who developed multiple thoracic and lumbar spinal metastases. The authors performed targeted exome sequencing on both the resected primary tumor and biopsied spinal metastases, which revealed 12 total variants of unknown clinical significance in genes associated with the PI3K/AKT/mTOR pathway, chromatin remodeling, DNA repair, and cell proliferation. Six of these variants were restricted to the metastatic lesion and included missense mutations with predicted functional effects in GRM3, DNMT3B, PLCG2, and SPEN. LESSONS: This report discusses the potential impact of these variants on tumor progression and metastasis, as well as the implications for identifying potential new biomarkers and therapies.

19.
World Neurosurg ; 179: e21-e31, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37348601

RESUMO

OBJECTIVE: Recruitment of diverse and talented students to the field of neurosurgery is key to its continued growth and scientific advancement. Barriers, including poor perceptions and lack of early exposure, can impact recruitment and have been compounded by the ongoing COVID-19 pandemic. This study examines the impact of an inaugural Neurosurgery Research Consortium meeting on premedical students, assessing whether this exposure generated interest and improved perceptions of a career in neurosurgery. METHODS: Premedical students were recruited to virtually attend an inaugural Neurosurgery Research Consortium developed by the affiliated medical school's American Association of Neurological Surgeons (AANS) Student Chapter. Questionnaires were distributed to students before and after the meeting to assess student demographics and perceptions of neurosurgery. RESULTS: A total of 54 students attended the meeting, with general interest in neurosurgery, medicine, and research opportunities being the primary factors for attendance. Following the research meeting, we found that students perceived neurosurgeons to be friendlier and more approachable, with a more positive quality of life (QoL). Overall perceptions of neurosurgery improved after the meeting, but perceptions among racial and ethnic minority students did not significantly change in the areas of diversity, inclusion, and equity. CONCLUSIONS: These results suggest recruitment strategies targeting undergraduate students may improve their perception of neurosurgery as a career, and may mitigate some barriers to entry. These strategies are cost effective and easily replicable, making an easily implementable approach to provide direct insight into neurosurgery for future medical students while also promoting academic efforts in the field of neurosurgery.


Assuntos
Neurocirurgia , Estudantes de Medicina , Humanos , Estados Unidos , Neurocirurgia/educação , Qualidade de Vida , Etnicidade , Pandemias , Estudantes Pré-Médicos , Escolha da Profissão , Grupos Minoritários , Inquéritos e Questionários
20.
bioRxiv ; 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38168388

RESUMO

Loss of nuclear TDP-43 occurs in a wide range of neurodegenerative diseases, and specific mutations in the TARDBP gene that encodes the protein are linked to familial Frontal Temporal Lobar Dementia (FTD), and Amyotrophic Lateral Sclerosis (ALS). Although the focus has been on neuronal cell dysfunction caused by TDP-43 variants, TARDBP mRNA transcripts are expressed at similar levels in brain endothelial cells (ECs). Since increased permeability across the blood brain barrier (BBB) precedes cognitive decline, we postulated that altered functions of TDP-43 in ECs contributes to BBB dysfunction in neurodegenerative disease. To test this hypothesis, we examined EC function and BBB properties in mice with either knock-in mutations found in ALS/FTLD patients (TARDBPG348C and GRNR493X) or EC-specific deletion of TDP-43 throughout the endothelium (Cdh5(PAC)CreERT2; Tardbpff) or restricted to brain endothelium (Slco1c1(BAC)CreERT2; Tardbpff). We found that TARDBPG348C mice exhibited increased permeability to 3kDa Texas Red dextran and NHS-biotin, relative to their littermate controls, which could be recapitulated in cultured brain ECs from these mice. Nuclear levels of TDP-43 were reduced in vitro and in vivo in ECs from TARDBPG348C mice. This coincided with a reduction in junctional proteins VE-cadherin, claudin-5 and ZO-1 in isolated ECs, supporting a cell autonomous effect on barrier function through a loss of nuclear TDP-43. We further examined two models of Tardbp deletion in ECs, and found that the loss of TDP-43 throughout the endothelium led to systemic endothelial activation and permeability. Deletion specifically within the brain endothelium acutely increased BBB permeability, and eventually led to hallmarks of FTD, including fibrin deposition, microglial and astrocyte activation, and behavioral defects. Together, these data show that TDP-43 dysfunction specifically within brain ECs would contribute to the BBB defects observed early in the progression of ALS/FTLD.

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