ABSTRACT
Glioblastoma (GBM) is an aggressive form of brain cancer that is highly resistant to therapy due to significant intra-tumoral heterogeneity. The lack of robust in vitro models to study early tumor progression has hindered the development of effective therapies. Here, we develop engineered GBM organoids (eGBOs) harboring GBM subtype-specific oncogenic mutations to investigate the underlying transcriptional regulation of tumor progression. Single-cell and spatial transcriptomic analyses revealed that these mutations disrupt normal neurodevelopment gene regulatory networks resulting in changes in cellular composition and spatial organization. Upon xenotransplantation into immunodeficient mice, eGBOs form tumors that recapitulate the transcriptional and spatial landscape of human GBM samples. Integrative single-cell trajectory analysis of both eGBO-derived tumor cells and patient GBM samples revealed the dynamic gene expression changes in developmental cell states underlying tumor progression. This analysis of eGBOs provides an important validation of engineered cancer organoid models and demonstrates their utility as a model of GBM tumorigenesis for future preclinical development of therapeutics.
ABSTRACT
BACKGROUND: The novel coronavirus disease 2019 (COVID-19) can be associated with various neurological manifestations, including cerebrovascular disease, seizures, peripheral nerve disease, and encephalitis. Intracranial abscess related to COVID-19 is rare but illustrates a serious complication in the studied cases. OBSERVATIONS: The authors report 3 cases of patients presenting with COVID-19 complicated by sinusitis with associated intracranial abscesses. Each patient underwent craniotomy with washout and sinus debridement during their hospital stay. All 3 patients improved to their baseline following treatment. Similar outcomes have been observed in other cases of intracranial abscess associated with COVID-19 infections. LESSONS: Patients achieved significant improvement following evacuation of the abscess and intravenous antibiotics. Further investigation is needed to determine treatment in relation to COVID-19, and the authors recommend following the standard treatment of intracranial abscess at this time.
ABSTRACT
Glioblastoma stem cells (GSCs) are an important subpopulation in glioblastoma, implicated in tumor growth, tumor recurrence, and radiation resistance. Understanding the cellular mechanisms for chemo- and radiation resistance could lead to the development of new therapeutic strategies. Here, we demonstrate that CDC20 promotes resistance to chemotherapy and radiation therapy. CDC20 knockdown does not increase TMZ- and radiation-induced DNA damage, or alter DNA damage repair, but rather promotes cell death through accumulation of the pro-apoptotic protein, Bim. Our results identify a CDC20 signaling pathway that regulates chemo- and radiosensitivity in GSCs, with the potential for CDC20-targeted therapeutic strategies in the treatment of glioblastoma.
Subject(s)
Brain Neoplasms , Glioblastoma , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Brain Neoplasms/radiotherapy , Cdc20 Proteins/genetics , Cdc20 Proteins/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line, Tumor , Glioblastoma/pathology , Humans , Neoplasm Recurrence, Local/pathology , Neoplastic Stem Cells/pathologyABSTRACT
Parkinson's Disease (PD) is the second most common neurodegenerative disease, characterized by progressive motor (such as resting tremor, hypokinesia, postural instability) and non-motor symptoms (such as neuropsychiatric decline and autonomic dysfunction). Since its introduction in the late 1980s, deep brain stimulation (DBS) has revolutionized the treatment of PD. Initially used in patients' with advanced PD with either medically refractory motor symptoms or medication intolerance, DBS typically provides excellent improvement in motor symptoms. Indications for DBS have continued to expand, with demonstrated efficacy in early PD and essential tremor, and promising preliminary results in the treatment of epilepsy, psychiatric disease, and depression. Advancements in DBS hardware, programming, neuroimaging, and surgical techniques have led to progressive improvement in efficacy and safety profiles. Thanks to ongoing research into remote programming, adaptive DBS, new targets, and alternative interventions, such as transcranial magnetic stimulation, the opportunities for further improvements in DBS and neuromodulation are bright.
Subject(s)
Deep Brain Stimulation , Neurodegenerative Diseases , Parkinson Disease , Humans , Parkinson Disease/therapy , Transcranial Magnetic Stimulation , Tremor/therapyABSTRACT
OBJECTIVE Risk of ischemia during aneurysm surgery is significantly related to temporary clipping time and final clipping that might incorporate a perforator. In this study, the authors attempted to assess the potential added benefit to patient outcomes of "awake" neurological testing when compared with standard neurophysiological testing performed under general anesthesia. The procedure is performed after the induction of conscious sedation, and for the neurological testing, the patient is fully awake. METHODS The authors conducted an institutional review board-approved prospective study of clipping unruptured intracranial aneurysms (UIAs) in 30 consecutive adult patients who underwent awake clipping. The end points were the incidence of stroke/cerebrovascular accident (CVA), death, discharge to a long-term facility, length of stay, and 30-day modified Rankin Scale score. All clinical and neurophysiological intraoperative monitoring data were recorded. RESULTS The median patient age was 52 years (range 27-63 years); 19 (63%) female and 11 (37%) male patients were included. Twenty-seven (90%) aneurysms were anterior, and 3 (10%) were posterior circulation aneurysms. Five (17%) had been coiled previously, 3 (10%) had been clipped previously, 2 (7%) were partially calcified, and 2 (7%) were fusiform aneurysms. Three patients developed synchronous clinical neurological and neurophysiological changes during temporary clipping with consequent removal of the temporary clip and reversal of those clinical and neurophysiological changes. Three patients developed asynchronous clinical neurological and neurophysiological changes. These 3 patients developed hemiparesis without changes in neurophysiological monitoring results. One patient developed linked clinical neurological and neurophysiological changes during final clipping that were not reversed by reapplication of the clip, and the patient had a CVA. Four patients with internal carotid artery ophthalmic segment aneurysms underwent visual testing with final clipping, and 1 of these patients required repositioning of the clip. Three patients who required permanent occlusion of a vessel as part of their aneurysm treatment underwent a 10-minute intraoperative clinical respective-vessel test occlusion. The median length of stay was 3 days (range 1-5 days). The median modified Rankin Scale score was 1 (range 0-3). All of the patients were discharged to home from the hospital except for 1 who developed a CVA and was discharged to a rehabilitation facility. There were no deaths in this series. CONCLUSIONS The 3 patients who developed neurological deterioration without a concomitant neurophysiological finding during temporary clipping revealed a potential advantage of awake aneurysm surgery (i.e., in decreasing the risk of ischemic injury).
Subject(s)
Intracranial Aneurysm/surgery , Intraoperative Neurophysiological Monitoring/methods , Postoperative Complications/prevention & control , Adult , Humans , Male , Middle Aged , Prospective Studies , Vascular Surgical Procedures/methods , WakefulnessABSTRACT
PURPOSE: To describe the subunit composition of glutamate and gamma-aminobutyric acid (GABA) receptors in brain tissue from patients with different types of status epilepticus. PATIENTS AND METHODS: The subunit composition of glutamate and GABA receptors was analyzed in: (1) surgical brain samples from three patients with refractory convulsive status epilepticus, three patients with electrical status epilepticus in sleep, and six patients with refractory epilepsy, and (2) brain autopsy samples from four controls who died without neurological disorders. Subunit expression was quantified with Western blotting and messenger ribonucleic acid (mRNA) expression was quantified with reverse polymerase chain reaction. RESULTS: Western blot analysis demonstrated the following patterns (as compared to controls): (1) alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors: elevated GluA1/GluA2 ratio in electrical status epilepticus in sleep (465%±119) and refractory epilepsy (329%±125; p<0.01); (2) N-methyl-d-aspartate (NMDA) receptors: increased GluN2B/GluN2A ratio in electrical status epilepticus in sleep (3682%±1000) and refractory convulsive status epilepticus (3520%±751; p<0.05); (3) GABA receptors: elevated α2/α1 ratio in refractory epilepsy (321%±138; p<0.05) and refractory convulsive status epilepticus (346%±74; p<0.05); and (4) patients with underlying malformation of cortical development had increased ratios in GluA1/GluA2 (382%±149; p<0.01), GluN2B/GluN2A (3321%±1581; p<0.05) and α2/α1 (303%±86; p<0.01). Quantification of mRNA demonstrated an elevated GABRA2/GABRA1 ratio in refractory epilepsy (712; p<0.05) as compared to controls. CONCLUSIONS: The subunit composition of glutamate and GABA receptors in patients with status epilepticus mirrors that found in animal models of refractory status epilepticus and may promote self-sustaining seizures. Receptor subunit changes may provide additional targets for improved treatment.
Subject(s)
Cerebral Cortex/metabolism , Protein Subunits/metabolism , Receptors, GABA/metabolism , Receptors, Glutamate/metabolism , Status Epilepticus/metabolism , Adolescent , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Young AdultABSTRACT
Neonatal seizures can be refractory to conventional anticonvulsants, and this may in part be due to a developmental increase in expression of the neuronal Na(+)-K(+)-2 Cl(-) cotransporter, NKCC1, and consequent paradoxical excitatory actions of GABAA receptors in the perinatal period. The most common cause of neonatal seizures is hypoxic encephalopathy, and here we show in an established model of neonatal hypoxia-induced seizures that the NKCC1 inhibitor, bumetanide, in combination with phenobarbital is significantly more effective than phenobarbital alone. A sensitive mass spectrometry assay revealed that bumetanide concentrations in serum and brain were dose-dependent, and the expression of NKCC1 protein transiently increased in cortex and hippocampus after hypoxic seizures. Importantly, the low doses of phenobarbital and bumetanide used in the study did not increase constitutive apoptosis, alone or in combination. Perforated patch clamp recordings from ex vivo hippocampal slices removed following seizures revealed that phenobarbital and bumetanide largely reversed seizure-induced changes in EGABA. Taken together, these data provide preclinical support for clinical trials of bumetanide in human neonates at risk for hypoxic encephalopathy and seizures.