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1.
Oncolytic Virother ; 4: 33-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27512668

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is a relentless primary central nervous system malignancy that remains resistant to conventional therapy despite major advances in clinical neurooncology. This report details the case of a patient who had failed conventional treatment for recurrent GBM and was ultimately treated with a genetically engineered herpes simplex virus (HSV) type 1 vector, G207. METHODS: Case report detailing the outcomes of one patient enrolled into the gene therapy arm of the Neurovir G207 protocol whereby stereotactic injection of 120 µL G207 viral suspension containing 1×10(7) plaque-forming units (or active viral particles) was made into the enhancing region of the tumor. RESULTS: In this patient, despite aggressive surgical resection, adjuvant radiotherapy and chemotherapy, tumor progression occurred. However, with G207 oncolytic therapy and brief exposures to second and third treatments, this patient had an extended survival time of 7.5 years and a 6-year apparent disease-free interval, an extraordinarily unusual finding in the pretemozolomide era. CONCLUSION: With minimal adjunctive chemotherapy, including one course of temozolomide, one course of procarbazine, and four cycles of irinotecan, the patient survived over 7 years before the next recurrence. Addition of G207 to this patient's traditional therapy may have been the critical treatment producing her prolonged survival. This report demonstrates the potential for long-term response to a one-time treatment with oncolytic HSV and encourages continued research on oncolytic viral therapy for GBM.

2.
J Biol Chem ; 289(17): 12168-12176, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24616106

RESUMO

The Drosophila Groucho protein and its mammalian orthologues the transducin-like enhancers of split (TLEs) are critical transcriptional corepressors that repress Wnt and other signaling pathways. Although it is known that Groucho/TLEs are recruited to target genes by pathway-specific transcription factors, molecular events after the corepressor recruitment are largely unclear. We report that association of TLEs with O-GlcNAc transferase, an enzyme that catalyzes posttranslational modification of proteins by O-linked N-acetylglucosamine, is essential for TLE-mediated transcriptional repression. Removal of O-GlcNAc from Wnt-responsive gene promoters is critical for gene activation from Wnt-responsive promoters. Thus, these studies identify a molecular mechanism by which Groucho/TLEs repress gene transcription and provide a model whereby O-GlcNAc may control distinct intracellular signaling pathways.


Assuntos
N-Acetilglucosaminiltransferases/metabolismo , Transdução de Sinais , Transducina/metabolismo , Via de Sinalização Wnt , Animais , Sequência de Bases , Imunoprecipitação da Cromatina , Primers do DNA , Drosophila , Humanos , Reação em Cadeia da Polimerase em Tempo Real
3.
J Neurosurg ; 118(6): 1356-62, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23611044

RESUMO

OBJECT: The April 27, 2011, tornados that affected the southeastern US resulted in 248 deaths in the state of Alabama. The University of Alabama at Birmingham (UAB) Medical Center, the largest Level I trauma center in the state, triaged and treated a large number of individuals who suffered traumatic injuries during these events, including those requiring neurosurgical assessment and treatment. METHODS: A retrospective review of all adult patients triaged at UAB Medical Center during the April 27, 2011, tornados was conducted. Those patients who were diagnosed with and treated for neurosurgical injuries were included in this cohort. RESULTS: The Division of Neurosurgery at UAB Medical Center received 37 consultations in the 36 hours following the tornado disaster. An additional patient presented 6 days later, having suffered a lumbar spine fracture that ultimately required operative intervention. Twenty-seven patients (73%) suffered injuries as a direct result of the tornados. Twenty-three (85%) of these 27 patients experienced spine and spinal cord injuries. Four patients (15%) suffered intracranial injuries and 2 patients (7%) suffered combined intracranial and spinal injuries. The spinal fractures that were evaluated and treated were predominantly thoracic (43.5%) and lumbar (43.5%). The neurosurgery service performed 14 spinal fusions, 1 ventriculostomy, 2 halo placements, 1 diagnostic angiogram, 1 endovascular embolectomy, and 1 wound debridement and lavage. Twenty-two patients (81.5%) were neurologically intact at discharge and all but 4 had 1 year of follow-up. Three patients had persistent deficits from spinal cord injuries and there was 1 death in a patient with multisystem injuries in whom no procedures were performed. Two patients experienced postoperative complications in the form of 1 wound infection and 1 stroke. CONCLUSIONS: The April 27, 2011, tornados in Alabama produced significant neurosurgical injuries that primarily involved the spine. There were a disproportionate number of patients with thoracolumbar fractures, a finding possibly due to the county medical examiner's postmortem findings that demonstrated a high prevalence of fatal cervical spine and traumatic brain injuries. The UAB experience can be used to aid other institutions in preparing for the appropriate allotment of resources in the event of a similar natural disaster.


Assuntos
Lesões Encefálicas/epidemiologia , Lesões Encefálicas/cirurgia , Procedimentos Neurocirúrgicos , Traumatismos da Coluna Vertebral/epidemiologia , Traumatismos da Coluna Vertebral/cirurgia , Tornados , Centros Médicos Acadêmicos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Alabama/epidemiologia , Lesões Encefálicas/patologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fusão Vertebral , Traumatismos da Coluna Vertebral/patologia , Resultado do Tratamento , Ventriculostomia , Adulto Jovem
4.
J Neurosurg Pediatr ; 8(6): 588-92, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22132917

RESUMO

OBJECT: A large volume of patients presented to a Level I pediatric trauma center during and after a recent tornado disaster. Injuries of the central and peripheral nervous systems and the medical responses of a pediatric neurosurgical team are reviewed. METHODS: The clinical courses of patients who suffered cranial, spinal, and peripheral nerve injuries due to the tornado storm are reported. The clinical actions taken by the neurosurgical team during and after the event are reviewed and the lessons learned are discussed. RESULTS: The tornado storm system moved through the Tuscaloosa and Birmingham metropolitan areas on the early evening hours of April 27, 2011. Twenty-four patients received care from the neurosurgical team. A total of 11 cranial (including placement of an external ventricular drain), 2 spine, and 2 peripheral procedures were performed for the victims. Nine procedures were performed within the first 12 hours of the event, and an additional 6 surgeries were performed in the following 24 hours. Injuries of the peripheral nervous system often presented in a delayed fashion. Several key components were identified that enabled adequate neurosurgical care for a large influx of acute patients. CONCLUSIONS: Massive casualties due to tornados are rare. A well-organized physician team working with the hospital administration may decrease the mortality and morbidity of such events.


Assuntos
Traumatismos dos Nervos Cranianos/cirurgia , Desastres , Neurocirurgia , Traumatismos dos Nervos Periféricos/cirurgia , Traumatismos da Coluna Vertebral/cirurgia , Tornados , Alabama , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Procedimentos Neurocirúrgicos/métodos , Centros de Traumatologia
5.
FEBS Lett ; 584(1): 49-54, 2010 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-19932102

RESUMO

The FOXO4 transcription factor plays an important role in cell survival in response to oxidative stress. The regulation of FOXO4 is orchestrated by post-translational modifications including phosphorylation, acetylation, and ubiquitination. Here, we demonstrate that O-GlcNAcylation also contributes to the FOXO4-dependent oxidative stress response. We show that hydrogen peroxide treatment of HEK293 cells increases FOXO4 association with OGT, the enzyme that adds O-GlcNAc to proteins, causing FOXO4 O-GlcNAcylation and enhanced transcriptional activity under acute oxidative stress. O-GlcNAcylation is known to be protective for cells under stress conditions, including oxidative stress. Our data provide a mechanism of FOXO4 anti-oxidative protection through O-GlcNAcylation.


Assuntos
Acetilglucosamina/metabolismo , Regulação da Expressão Gênica , Estresse Oxidativo/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Acilação , Proteínas de Ciclo Celular , Linhagem Celular , Fatores de Transcrição Forkhead , Humanos , N-Acetilglucosaminiltransferases/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo
6.
Glycobiology ; 16(6): 551-63, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16505006

RESUMO

Although the knowledge that nuclear and cytoplasmic proteins are modified with N-acetylglucosamine has existed for decades, little has been shown as to its function until recently. There are now substantial data highlighting the significance of proper regulation of this modification in multiple cellular processes. Currently, only two enzymes are known that regulate this modification. O-GlcNAc transferase (OGT) modifies protein substrates posttranslationally by adding the N-acetylglucosamine. Bifunctional nuclear/cytoplasmic O-GlcNAcase and acetyl transferase (NCOAT) is responsible for cleaving the modification from target proteins. Here, we demonstrate for the first time an unusual association of these two opposing enzymes into a single O-GlcNAczyme complex. NCOAT and OGT associate strongly through specific domains such that NCOAT accompanies OGT, with histone deacetylases (HDACs), into transcription corepression complexes. Exclusion of NCOAT activities from OGT association blocks proper estrogen-dependent cell signaling as well as mammary development in transgenic mice. This demonstrates that NCOAT is in a strategic position to rapidly counteract OGT and HDAC without requiring its recruitment.


Assuntos
Acetilglucosamina/metabolismo , Acetilglucosaminidase/metabolismo , Histona Acetiltransferases/metabolismo , Histona Desacetilases/metabolismo , Complexos Multienzimáticos/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Transdução de Sinais/fisiologia , Acetilglucosaminidase/genética , Animais , Linhagem Celular , Estrogênios/fisiologia , Feminino , Histona Acetiltransferases/genética , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/metabolismo , Camundongos , Camundongos Transgênicos , Complexos Multienzimáticos/genética , N-Acetilglucosaminiltransferases/genética , beta-N-Acetil-Hexosaminidases
7.
J Biol Chem ; 279(51): 53665-73, 2004 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-15485860

RESUMO

Histones and transcription factors are regulated by a number of post-translational modifications that in turn regulate the transcriptional activity of genes. These modifications occur in large, multisubunit complexes. We have reported previously that mSin3A can recruit O-GlcNAc transferase (OGT) along with histone deacetylase into such a corepressor complex. This physical association allows OGT to act cooperatively with histone deacetylation in gene repression by catalyzing the O-GlcNAc modification on specific transcription factors to inhibit their activity. For rapid, reversible gene regulation, the enzymes responsible for the converse reactions must be present. Here, we report that O-GlcNAcase, which is responsible for the removal of O-GlcNAc additions on nuclear and cytosolic proteins, possesses intrinsic histone acetyltransferase (HAT) activity in vitro. Free as well as reconstituted nucleosomal histones are substrates of this bifunctional enzyme. This protein, now termed NCOAT (nuclear cytoplasmic O-GlcNAcase and acetyltransferase) has a typical HAT domain that has both active and inactive states. This finding demonstrates that NCOAT may be regulated to reduce the state of glycosylation of transcriptional activators while increasing the acetylation of histones to allow for the concerted activation of eukaryotic gene transcription.


Assuntos
Acetilglucosaminidase/química , Acetiltransferases/química , Complexos Multienzimáticos/química , Acetilação , Sequência de Aminoácidos , Animais , Sítios de Ligação , Núcleo Celular/metabolismo , Cromatografia em Gel , Clonagem Molecular , Citosol/metabolismo , Células HeLa , Hexosaminidases/química , Histona Acetiltransferases , Histonas/química , Humanos , Imunoprecipitação , Lisina/química , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Nucleossomos/metabolismo , Peptídeos/química , Plasmídeos/metabolismo , Mutação Puntual , Ligação Proteica , Conformação Proteica , Processamento de Proteína Pós-Traducional , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/química , Homologia de Sequência de Aminoácidos , Estreptozocina/farmacologia , Transcrição Gênica , beta-N-Acetil-Hexosaminidases
8.
Cancer Res ; 63(24): 8670-3, 2003 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-14695179

RESUMO

Malignant gliomas are the most common primary brain tumors in adults, and the most malignant form, glioblastoma multiforme (GBM), is usually rapidly fatal. Most GBMs do not have p53 mutations, although the p53 tumor suppressor pathway appears to be inactivated. GBMs grow in a hypoxic and inflammatory microenvironment, and increased levels of the free radicals nitric oxide (NO) and superoxide () occur in these malignancies in vivo. Peroxynitrite (ONOO(-)) is a highly reactive molecule produced by excess NO and that can posttranslationally modify and inactivate proteins, especially zinc finger transcription factors such as p53. We demonstrated previously that GBMs have evidence of tyrosine nitration, the "footprint" of peroxynitrite-mediated protein modification in vivo, and that peroxynitrite could inhibit the specific DNA binding ability of wild-type p53 protein in glioma cells in vitro. Here we show that both authentic peroxynitrite and SIN-1 (3-morpholinosydnonimine hydrochloride), a molecule that decomposes into NO and to form peroxynitrite, can inhibit wild-type p53 function in malignant glioma cells. Concentrations of peroxynitrite associated with a tumor inflammatory environment caused dysregulation of wild-type p53 transcriptional activity and downstream p21(WAF1) expression.


Assuntos
Glioblastoma/tratamento farmacológico , Molsidomina/análogos & derivados , Ácido Peroxinitroso/farmacologia , Espécies Reativas de Nitrogênio/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Proteína Supressora de Tumor p53/antagonistas & inibidores , Linhagem Celular Tumoral , Doxiciclina/farmacologia , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Molsidomina/farmacocinética , Molsidomina/farmacologia , Ácido Peroxinitroso/farmacocinética , Espécies Reativas de Nitrogênio/farmacocinética , Espécies Reativas de Oxigênio/farmacocinética , Ativação Transcricional/efeitos dos fármacos , Transfecção , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/fisiologia
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