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1.
Oncolytic Virother ; 4: 33-8, 2015.
Article in English | MEDLINE | ID: mdl-27512668

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-24616106

ABSTRACT

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.


Subject(s)
N-Acetylglucosaminyltransferases/metabolism , Signal Transduction , Transducin/metabolism , Wnt Signaling Pathway , Animals , Base Sequence , Chromatin Immunoprecipitation , DNA Primers , Drosophila , Humans , Real-Time Polymerase Chain Reaction
3.
J Neurosurg ; 118(6): 1356-62, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23611044

ABSTRACT

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.


Subject(s)
Brain Injuries/epidemiology , Brain Injuries/surgery , Neurosurgical Procedures , Spinal Injuries/epidemiology , Spinal Injuries/surgery , Tornadoes , Academic Medical Centers/statistics & numerical data , Adolescent , Adult , Aged , Alabama/epidemiology , Brain Injuries/pathology , Cohort Studies , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Prevalence , Retrospective Studies , Spinal Fusion , Spinal Injuries/pathology , Treatment Outcome , Ventriculostomy , Young Adult
4.
J Neurosurg Pediatr ; 8(6): 588-92, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22132917

ABSTRACT

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.


Subject(s)
Cranial Nerve Injuries/surgery , Disasters , Neurosurgery , Peripheral Nerve Injuries/surgery , Spinal Injuries/surgery , Tornadoes , Alabama , Child , Child, Preschool , Female , Humans , Male , Neurosurgical Procedures/methods , Trauma Centers
5.
FEBS Lett ; 584(1): 49-54, 2010 Jan 04.
Article in English | MEDLINE | ID: mdl-19932102

ABSTRACT

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.


Subject(s)
Acetylglucosamine/metabolism , Gene Expression Regulation , Oxidative Stress/genetics , Transcription Factors/metabolism , Transcription, Genetic , Acylation , Cell Cycle Proteins , Cell Line , Forkhead Transcription Factors , Humans , N-Acetylglucosaminyltransferases/metabolism , beta-N-Acetylhexosaminidases/metabolism
6.
Glycobiology ; 16(6): 551-63, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16505006

ABSTRACT

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.


Subject(s)
Acetylglucosamine/metabolism , Acetylglucosaminidase/metabolism , Histone Acetyltransferases/metabolism , Histone Deacetylases/metabolism , Multienzyme Complexes/metabolism , N-Acetylglucosaminyltransferases/metabolism , Signal Transduction/physiology , Acetylglucosaminidase/genetics , Animals , Cell Line , Estrogens/physiology , Female , Histone Acetyltransferases/genetics , Mammary Glands, Animal/cytology , Mammary Glands, Animal/metabolism , Mice , Mice, Transgenic , Multienzyme Complexes/genetics , N-Acetylglucosaminyltransferases/genetics , beta-N-Acetylhexosaminidases
7.
J Biol Chem ; 279(51): 53665-73, 2004 Dec 17.
Article in English | MEDLINE | ID: mdl-15485860

ABSTRACT

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.


Subject(s)
Acetylglucosaminidase/chemistry , Acetyltransferases/chemistry , Multienzyme Complexes/chemistry , Acetylation , Amino Acid Sequence , Animals , Binding Sites , Cell Nucleus/metabolism , Chromatography, Gel , Cloning, Molecular , Cytosol/metabolism , HeLa Cells , Hexosaminidases/chemistry , Histone Acetyltransferases , Histones/chemistry , Humans , Immunoprecipitation , Lysine/chemistry , Molecular Sequence Data , Mutagenesis, Site-Directed , Nucleosomes/metabolism , Peptides/chemistry , Plasmids/metabolism , Point Mutation , Protein Binding , Protein Conformation , Protein Processing, Post-Translational , Protein Structure, Secondary , Protein Structure, Tertiary , Rats , Rats, Sprague-Dawley , Recombinant Proteins/chemistry , Sequence Homology, Amino Acid , Streptozocin/pharmacology , Transcription, Genetic , beta-N-Acetylhexosaminidases
8.
Cancer Res ; 63(24): 8670-3, 2003 Dec 15.
Article in English | MEDLINE | ID: mdl-14695179

ABSTRACT

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.


Subject(s)
Glioblastoma/drug therapy , Molsidomine/analogs & derivatives , Peroxynitrous Acid/pharmacology , Reactive Nitrogen Species/pharmacology , Reactive Oxygen Species/pharmacology , Tumor Suppressor Protein p53/antagonists & inhibitors , Cell Line, Tumor , Doxycycline/pharmacology , Glioblastoma/genetics , Glioblastoma/metabolism , Humans , Molsidomine/pharmacokinetics , Molsidomine/pharmacology , Peroxynitrous Acid/pharmacokinetics , Reactive Nitrogen Species/pharmacokinetics , Reactive Oxygen Species/pharmacokinetics , Transcriptional Activation/drug effects , Transfection , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/physiology
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