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1.
World Neurosurg ; 182: 208-213, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061539

RESUMO

BACKGROUND: Exoscope use in spinal neurosurgery has become a promising surgical option providing enhanced operative field visibility and ergonomics. However, data on its use in spine surgery are underreported in the literature. We aimed to assess the intraoperative outcomes in exoscope-assisted spine surgery compared with similar procedures performed using the operative microscope. METHODS: A retrospective review was performed of all spinal surgeries performed using an exoscope and, subsequently, an equal number of operative microscope cases performed by 2 senior surgeons at a single institution from 2016 to 2023. The variables included demographics, clinical presentation, surgical treatment, and operative outcomes. RESULTS: A total of 123 exoscope spinal surgeries were performed on 116 unique patients with a mean age of 67 ± 14 years, of whom 60 (52%) were women. The microscope group included 126 surgeries on 120 unique patients with a mean age of 62 ± 14 years, of whom 53 (45%) were women. The mean blood loss (28 mL vs. 132 mL; P = 0.0009), operative time (83 minutes vs. 103 minutes; P = 0.006), and length of stay (1.04 days vs. 1.73 days; P = 0.02) were significantly less for the exoscope group than for the microscope group. CONCLUSIONS: The use of the exoscope resulted in a shorter operative time, less blood loss, a shorter length of stay, and favorable clinical outcomes compared with the use of the operative microscope. Neurosurgeons should consider this seemingly efficacious and ergonomically favorable visual technology for spinal surgeries.


Assuntos
Neurocirurgia , Procedimentos Neurocirúrgicos , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Procedimentos Neurocirúrgicos/métodos , Coluna Vertebral/cirurgia , Microscopia , Microcirurgia/métodos
2.
World Neurosurg ; 168: e460-e470, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36202341

RESUMO

OBJECTIVE: To investigate impact of patient factors and sacroiliac joint (SIJ) anatomical structure on SIJ fusion outcomes. METHODS: This single-center, retrospective, observational study evaluated patients diagnosed with SIJ dysfunction refractory to conservative measures who had available preoperative imaging of the sacrum and underwent SIJ fusion surgery. The impact of patient sociodemographics on pain improvement was assessed by Mann-Whitney U test. Differences in patient sociodemographics and outcome information between anatomical subtypes were assessed with χ2 and Kruskal-Wallis tests. χ2 test was used to compare joint anatomy distribution between studies analyzing SIJ variations. RESULTS: We included 77 total joints that underwent instrumentation. There were significant differences between the anatomical subtypes with female sex having significantly higher rates of non-normal joint anatomy. Younger age was significantly more common in bipartite/dysmorphic anatomy (53.9 years) than normal anatomy (70 years) (P < 0.05). There was a trend toward better outcomes in bipartite/dysmorphic and accessory variants, while semicircular defect and crescent variants trended toward worse outcomes. Nonnormal anatomy was significantly more frequent in our population than previous reports on nonpathological SIJ. CONCLUSIONS: A pathological SIJ has a significantly higher prevalence of variant joint anatomy. There appears to be a trend toward differences in surgical outcomes based on SIJ anatomy. Future research with larger sample sizes is necessary to confirm these differences.


Assuntos
Doenças da Coluna Vertebral , Fusão Vertebral , Humanos , Feminino , Pessoa de Meia-Idade , Articulação Sacroilíaca/diagnóstico por imagem , Articulação Sacroilíaca/cirurgia , Fusão Vertebral/métodos , Doenças da Coluna Vertebral/cirurgia , Sacro , Estudos Retrospectivos
3.
Clin Neurol Neurosurg ; 216: 107218, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35367747

RESUMO

Few cases have been reported of the diagnosis and treatment of glioblastoma (GB) during pregnancy. Subsequently, surgical, medical, and obstetrical management of complicated primary central nervous system malignancy in antepartum and postpartum patients remains under-investigated. The authors report the case of a 24-year-old female patient who developed generalized tonic-clonic seizures and focal neurologic deficits. MRI imaging (3T Skyra, Siemens, Erlangen, Germany) revealed an intracranial mass suspicious for malignant tumor and surgical resection under awake sedation was scheduled. The patient was incidentally found to be in her first trimester of pregnancy. Using neuronavigation, neurophysiologic monitoring, and conscious sedation the tumor was debulked successfully and histopathologic analysis confirmed giant cell glioblastoma, WHO Grade IV, 1p/19q intact, IDH wild-type, with NF1 p.Y2285fs and RB1 p.S318fs somatic mutations. Post-surgical oncologic management continued with fractioned radiotherapy and use of the Optune® device. The patient underwent uncomplicated cesarean section at 34-weeks gestation, the child remains healthy and the patient remains disease-disease free at 1-year. Thus, this case presents an approach to management of complicated GBM during first trimester pregnancy.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Criança , Humanos , Gravidez , Feminino , Adulto Jovem , Adulto , Glioblastoma/diagnóstico por imagem , Glioblastoma/cirurgia , Glioblastoma/genética , Neoplasias Encefálicas/patologia , Vigília , Cesárea , Craniotomia/métodos
4.
J Neurosurg ; : 1-8, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35180701

RESUMO

Phanor Leonidas Perot Jr., MD, PhD (1928-2011), was a gifted educator and pioneer of academic neurosurgery in South Carolina. As neurosurgical resident and then as a junior faculty member at the Montreal Neurological Institute, he advanced understandings of both epilepsy and spinal cord injury under Wilder Penfield, William Cone, and Theodore Rasmussen. In 1968, he moved to Charleston to lead neurosurgery. From his time spent with master physicians such as Isidor Ravdin and Wilder Penfield, Perot himself became "the ultimate teacher." His research spanned the fields of epilepsy to torticollis to spinal trauma, focusing the most on the basic pathophysiology of spinal cord damage elucidated through somatosensory evoked potentials. His research was distinguished by generous grant funding. By the time he stepped down as chairman in 1997, the division of neurosurgery had become a department and he had served as president of the American Academy of Neurological Surgery and the Society of Neurological Surgeons. Perot taught prolifically at the bedside, and considered the residency program at the Medical University of South Carolina his greatest achievement. Although Dr. Perot never fully retired, he also enjoyed active hobbies of fly-fishing, traveling, and hunting, until his death on February 2, 2011. He influenced many and earned his role in history as the father of academic neurosurgery in South Carolina.

5.
World Neurosurg ; 161: e61-e74, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35032716

RESUMO

BACKGROUND: Glioblastoma (GB) is an aggressive tumor showing extensive intertumoral and intratumoral heterogeneity. Several possible reasons contribute to the historical inability to develop effective therapeutic strategies for treatment of GB. One such challenge is the inability to consistently procure high-quality biologically preserved specimens for use in molecular research and patient-derived xenograft model development. No scientifically derived standardized method exists for intraoperative tissue collection specifically designed with the fragility of RNA in mind. METHODS: In this investigation, we set out to characterize matched specimens from 6 GB patients comparing the traditional handling and collection processes of intraoperative tissue used in most neurosurgical operating rooms versus an automated resection, collection, and biological preservation system (APS) which captures, preserves, and biologically maintains tissue in a prescribed and controlled microenvironment. Matched specimens were processed in parallel at various time points and temperatures, evaluating viability, RNA and protein concentrations, and isolation of GB cell lines. RESULTS: We found that APS-derived GB slices stored in an APS modified medium remained viable and maintained high-quality RNA and protein concentration for up to 24 hours. CONCLUSIONS: Our results showed that primary GB cell cultures derived in this manner had improved growth over widely used collection and preservation methods. By implementing an automated intraoperative system, we also eliminated inconsistencies in methodology of tissue collection, handling and biological preservation, establishing a repeatable and standardized practice that does not require additional staff or a laboratory technician to manage it.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Glioblastoma/patologia , Glioblastoma/cirurgia , Humanos , Projetos Piloto , Preservação Biológica , RNA , Preservação de Tecido/métodos , Microambiente Tumoral
6.
J Mol Neurosci ; 71(8): 1714-1722, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33595778

RESUMO

The P53N gene maps precisely to human chromosome sub-band 22q12.1-12.3, a region where loss of heterozygosity has been reported in 30% of astrocytic tumors and associated with progression to anaplasia. Moreover, a putative tumor suppressor gene has been indicated on 22q11 region involved in pathogenesis of ependymal tumors. Our objectives to examine the expression level of novel membrane-associated protein (termed P53N) encoded by a novel human gene on chromosome 22q12.1-12.3 in glioblastomas and ependymomas. Serial analysis of gene expression (SAGE) and immunofluorescence analysis of the P53N in the brain tumor tissues were performed. Our analysis revealed that there was high expression of the P53N mRNA in brain ependymoma and brain well-differentiated astrocytoma libraries. The P53N protein. P53N protein contains a high mobility group (HMG) domain at amino acid positions 301 to 360 expressed highly in glioblastoma and ependymoma specimens. Anti-P53N carboxyl-terminal peptide antibody localized the P53N protein to the cytoplasmic membranes of protoplasmic astrocytes in the glioblastoma and ependymoma specimens. These results are in good agreement with the SAGE analysis and the predicted transmembrane topology for the P53N protein and support a possible transmembrane model in which the P53N contains a predicted transmembrane region with its amino terminus localized to the inside of the cytoplasmic membrane.


Assuntos
Neoplasias Encefálicas/metabolismo , Cromossomos Humanos Par 22/genética , Ependimoma/metabolismo , Glioblastoma/metabolismo , Proteínas de Grupo de Alta Mobilidade/genética , Neoplasias Encefálicas/genética , Clonagem Molecular , Ependimoma/genética , Glioblastoma/genética , Proteínas de Grupo de Alta Mobilidade/química , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , Domínios Proteicos
7.
J Neurol Sci ; 418: 117102, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32866816

RESUMO

Temozolomide (TMZ) therapy is the standard of care for patients with glioblastoma (GBM). Clinical studies have shown that elevated levels of DNA repair protein O (6)-methylguanine-DNA methyltransferase (MGMT) or deficiency/defect of DNA mismatch repair (MMR) genes is associated with TMZ resistance in some, but not all, GBM tumors. Another reason for GBM treatment failure is signal redundancy due to coactivation of several functionally linked receptor tyrosine kinases (RTKs), including anaplastic lymphoma kinase (ALK) and c-Met (hepatocyte growth factor receptor). As such, these tyrosine kinases serve as potential targets for GBM therapy. Thus, we tested two novel drugs: INC280 (Capmatinib: a highly selective c-Met receptor tyrosine kinase-RTK inhibitor) and LDK378 (Ceritinib: a highly selective anaplastic lymphoma kinase-ALK inhibitor), aiming to overcome TMZ resistance in MGMT-unmethylated GBM cells in in vitro cell culture models. Treatments were examined using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, caspase-3 assay and western blot analysis. Results obtained from our experiments demonstrated that preconditioning with INC280 and LDK378 drugs exhibit increased MMR protein expression, specifically MMR protein MLH1 (MutL Homolog 1) and MSH6 (MutS Homolog 6) and sensitized TMZ in MGMT-unmethylated GBM cells via suppression of ALK and c-Met expression. INC280 and LDK378 plus TMZ also induced apoptosis by modulating downstream signaling of PI3K/AKT/STAT3. Taken together, this data indicates that co-inhibition of ALK and c-MET can enhance growth inhibitory effects in MGMT-unmethylated cells and enhance TMZ sensitivity in-vitro, suggesting c-Met inhibitors combined with ALK-targeting provide a therapeutic benefit in MGMT-unmethylated GBM patients.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Preparações Farmacêuticas , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Benzamidas , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Imidazóis , Fosfatidilinositol 3-Quinases , Pirimidinas , Sulfonas , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Triazinas , Proteínas Supressoras de Tumor/genética
8.
SN Compr Clin Med ; 2(6): 836-843, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32704621

RESUMO

BACKGROUND: Current treatments for glioblastoma (GB), the most common and malignant primary brain tumor are inadequate and as such, the median survival for most patients with GB is on the order of months, even after cytoreductive surgery, radiation and chemotherapy. CASE DESCRIPTION: Current study reports two cases of glioblastoma (GB) with subventricular zone (SVZ) involvement. SVZ biopsies demonstrated the presence of hypercellularity, nestin immunoreactivity, and a Ki-67 labeling index (LI) of 1-2%. Interestingly, tumor morphology and proliferative indices are different in the SVZ specimens than the hemispheric recurrences, which displayed similar nestin immunoreactivity, but a greater LI of 10%. Biopsy specimens demonstrated both intense nestin immunoreactivity and GFAP immunoreactivity in and around the GB recurrence. Nestin positive cells were more abundant closer to the SVZ nearest to the dorsolateral horn of the left lateral ventricle, while GFAP immunoreactivity was more intense closer to the center of the tumor recurrence. Additionally, co-labeling of cells with Ki67 and several different progenitor markers (CD133, CD140, TUJ-1, and nestin) demonstrated that these cells found in and around the GB recurrence were actively dividing. Having failed standard therapy with evidence of bi-hemispheric spread and progression to GB, we report a novel approach of using intraventricular liposomal encapsulated cytarabine (DepoCyt) for the treatment for GB by suppressing glial progenitor cells that surround the ventricular system in patients with GB. CONCLUSIONS: MRI and immunohistochemistry demonstrated that the SVZ is the incubator for future recurrences of GB and propose targeting SVZ progenitor cells with intraventricular liposomal encapsulated Ara-C. Two patients treated using this novel regimen have demonstrated partial radiographic responses warranting further studies looking at targeting the subventricular zone.

9.
J Mol Neurosci ; 70(9): 1415-1424, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32367506

RESUMO

Allelic losses of the q13.3 region of chromosome 19 have been documented in all major types of diffuse gliomas, strongly suggesting the presence of a 19q13.3 tumor suppressor gene responsible for these malignancies. The P78 gene precisely maps to 19q13.3, the glioma candidate region, and encodes a recently identified novel protein (P78). The purpose of this study was to determine P78 protein expression in gliomas. Serial analysis of gene expression (SAGE) reveals P78 mRNA expression to be significantly reduced in high-grade gliomas such as glioblastoma (GB), as compared with the low-grade tumors including astrocytomas, oligodendrogliomas, and ependymomas. We observed the distribution of staining of P78 protein was concentrated on the cell membranes of the luminal epithelial cells, not cytoplasm. In contrast, the pre-immune serum controls demonstrated no staining. These results demonstrate that P78 protein is highly expressed in the cytoplasmic membranes of low but not high-grade astrocytomas, and correlates with grade of malignancy. In these double immunostaining experiments, the anti-Map-2 and anti-NeuN antibodies did not stain round cells that were stained with the anti-P78 carboxyl-terminal peptide antibodies, demonstrating that these round cells were not neurons, and likely protoplasmic astrocytes. Current results also suggest that the astrocytes stained with the anti-P78 carboxyl-terminal peptide antibody are likely protoplasmic astrocytes. We also observed preincubation of anti-P78 carboxyl-terminal antibodies with immunizing peptides abolished immunostaining in gliomas. These results suggest a role for the P78 protein in the process of abnormal growth in glial tumors.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , Complexo Mediador/genética , Encéfalo/metabolismo , Neoplasias Encefálicas/patologia , Membrana Celular/metabolismo , Cromossomos Humanos Par 19/genética , Células Epiteliais/metabolismo , Glioma/patologia , Humanos , Complexo Mediador/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Cancer Invest ; 38(6): 349-355, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32441531

RESUMO

Background: Meningiomas represent ∼30% of primary central nervous system (CNS) tumors. Although advances in surgery and radiotherapy have significantly improved survival, there remains an important subset of patients whose tumors have more aggressive behavior and are refractory to conventional therapy. Recent advances in molecular genetics and epigenetics suggest that this aggressive behavior may be due to the deletion of the DNA repair and tumor suppressor gene, CHEK2, neurofibromatosis Type 2 (NF2) mutation on chromosome 22q12, and genetic abnormalities in multiple RTKs including FGFRs. Management of higher-grade meningiomas, such as anaplastic meningiomas (AM: WHO grade III), is truly challenging and there isn't an established chemotherapy option. We investigate the effect of active multi tyrosine receptor kinase inhibitor Dovitinib at stopping AM cell growth in in vitro with either frequent codeletion or mutated CHEK2 and NF2 gene.Methods: Treatment effects were assessed using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, western blot analysis, caspases assay, and DNA fragmentation assay.Results: Treatment of CH157MN and IOMM-Lee cells with Dovitinib suppressed multiple angiokinases-mainly FGFRs, leading to suppression of downstream signaling by RAS-RAF-MAPK molecules and PI3K-AKT molecules which are involved in cell proliferation, cell survival, and tumor invasion. Furthermore, Dovitinib induced apoptosis via downregulation of survival proteins (Bcl-XL), and over-expression of apoptotic factors (Bax and caspase-3) regardless of CHEK2 and NF2 mutation status.Conclusions: This study establishes the groundwork for the development of Dovitinib as a therapeutic agent for high-grade AM with either frequent codeletion or mutated CHEK2 and NF2, an avenue with high translational potential.


Assuntos
Benzimidazóis/farmacologia , Quinase do Ponto de Checagem 2/genética , Meningioma/tratamento farmacológico , Neurofibromina 2/genética , Quinolonas/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Meningioma/genética , Meningioma/patologia , Mutação/genética , Estadiamento de Neoplasias , Fosfatidilinositol 3-Quinases/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Receptores de Fatores de Crescimento de Fibroblastos/genética , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/genética , Proteína bcl-X/genética
11.
Oncolytic Virother ; 7: 107-116, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538967

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is an aggressive form of brain cancer which is associated with poor prognosis. A variety of oncolytic viruses have previously shown positive efficacy against GBM, potentially offering new treatment options for patients. One such oncolytic virus is Myxoma virus (MYXV), a rabbit-specific poxvirus that has been shown to be efficacious against a variety of tumor models including GBM. PURPOSE: The purpose of this study was to test the efficacy of MYXV combined with current treatment regimens for GBM in both established cell lines as well as patient biopsy samples. MATERIALS AND METHODS: U118 gliobastoma cell lines were treated under various standard of care combinations (untreated, radiation and chemotherapeutic) prior to infection with MYXV. Infection was then monitored for differences in rate of infection, titer and rate of spread. Cellular death was measured by MTT assay and Caspase-3 colorimetric assay. Patient biopsies were harvested and treated under similar treatment conditions. RESULTS: The addition of GBM standard of care to MYXV infection resulted in an increased rate of spread compared to single treatment with either radiation or chemotherapeutic alone. SOC did not alter viral replication or infection rates. Similar effects were seen in ex vivo patient biopsies. Cellular viability was significantly decreased with the combination therapy of SOC and MYXV infection compared to any other treatment outcome. Caspase-3 activity was also significantly increased in samples treated with combination therapy when compared to any other treatment combination. CONCLUSION: Our results show that the combination of MYXV with current SOC results in both increased killing of GBM cells compared to either treatment regime alone as well as increased spread of MYXV infection. These findings lay the foundation for future in vivo studies on combining MYXV with GBM SOC.

12.
Cancer Chemother Pharmacol ; 82(6): 945-952, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30209569

RESUMO

PURPOSE/INTRODUCTION: Glioblastoma (GB) remains incurable despite aggressive chemotherapy, radiotherapy, and surgical interventions; immunotherapies remain experimental in clinical practice. Relevant preclinical models that can accurately predict tumor response to therapy are equally challenging. This study aimed to validate the effect of the naturally occurring agent diallyl trisulfide (DATS) in human GB in relevant pre-clinical models. METHODS: Ex vivo slice culture, in vivo cell line derived orthotopic xenograft and patient-derived orthotopic xenograft (PDX) animal models of GB were utilized to assess efficacy of treatment with DATS. RESULTS: Our results showed 72-h treatments of 25 µM DATS induced cell death in ex vivo human GB slice culture. We treated U87MG orthotopic xenograft models (U87MGOX) and patient-derived orthotopic xenograft models (PDX) with daily intraperitoneal injections of DATS for 14 days. Magnetic resonance (MR) imaging of mice treated with DATS (10 mg/kg) demonstrated reduced tumor size at 5 weeks when compared with saline-treated U87MGOX and PDX controls. Hematoxylin (H&E) staining demonstrated dose-dependent reduction in gross tumor volume with decreased proliferation and decreased angiogenesis. Western blotting showed that DATS was associated with increases in histone acetylation (Ac-Histone H3/H4) and activated caspase-3 in this novel preclinical model. Histological assessment and enzyme assays showed that even the highest dose of DATS did not negatively impact hepatic function. CONCLUSIONS: DATS may be an effective and well-tolerated therapeutic agent in preventing tumor progression and inducing apoptosis in human GB.


Assuntos
Compostos Alílicos/uso terapêutico , Glioblastoma/tratamento farmacológico , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/metabolismo , Sulfetos/uso terapêutico , Compostos Alílicos/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Glioblastoma/enzimologia , Glioblastoma/patologia , Inibidores de Histona Desacetilases/administração & dosagem , Humanos , Masculino , Camundongos SCID , Neurônios/efeitos dos fármacos , Neurônios/patologia , Sulfetos/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Neurocase ; 24(1): 7-9, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29310506

RESUMO

Agreeing with Damasio's statement defining the "process" of consciousness, we propose the self as created by mind-based knowledge and a combination of images of an organism's intentional motor responses interacting with its environment. The lemniscal system, with plastic capabilities, manages gravity in voluntary movement. The spinal segment motor reflex represents the schema of gravity-managing neuronal activity, and it can become "nested" in cortical areas participating in consciousness-building, allowing consideration of the brain as a hyper-evolved nervous system segment harboring atavic spinal organization. Consciousness' capability to change itself makes humans co-participants in their own mental and consciousness evolution.


Assuntos
Encéfalo/citologia , Estado de Consciência/fisiologia , Internato e Residência , Neurônios/fisiologia , Neurocirurgia , Encéfalo/fisiologia , Humanos
14.
Childs Nerv Syst ; 33(3): 429-436, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27942918

RESUMO

BACKGROUND: Immunotherapy can be an effective treatment for pediatric medulloblastoma (MB) patients. However, major subpopulations do not respond to immunotherapy, due to the lack of antigenic mutations or the immune-evasive properties of MB cells. Clinical observations suggest that radiation therapy (RT) may expand the therapeutic reach of immunotherapy. The aim of the present investigation is to study the effect of low-dose X-ray radiation (LDXR, 1 Gy) on the functional immunological responses of MB cells (DAOY, D283, and D341). METHODS: Induction of MB cell death was examined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Production of reactive oxygen species (ROS) was measured by fluorescent probes. Changes in the expression of  human leukocyte antigen (HLA) molecules and caspase-3 activities during treatment were analyzed using Western blotting and caspase-3 assay. RESULTS: Western blot analysis demonstrated that LDXR upregulated the expression of HLA class I and HLA II molecules by more than 20% compared with control and high-dose (12 Gy) groups in vitro. Several of these HLA subtypes, such as MAGE C1, CD137, and ICAM-1, have demonstrated upregulation. In addition, LDXR increases ROS production in association with phosphorylation of NF-κB and cell surface expression of mAb target molecules (HER2 and VEGF). These data suggest that a combined LDXR and mAb therapy can create a synergistic effect in vitro. CONCLUSION: These results suggest that LDXR modulates HLA molecules, leading to alterations in T-cell/tumor-cell interaction and enhancement of T-cell-mediated MB cell death. Also, low-dose radiotherapy combined with monoclonal antibody therapy may one day augment the standard treatment for MB, but more investigation is needed to prove its utility as a new therapeutic combination for MB patients.


Assuntos
Anticorpos Monoclonais/farmacologia , Linhagem Celular Tumoral/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Antígenos HLA/metabolismo , Meduloblastoma/metabolismo , Radiação , Ligante 4-1BB/metabolismo , Análise de Variância , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta à Radiação , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Antígenos HLA/imunologia , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Meduloblastoma/patologia , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor ErbB-2/imunologia , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/imunologia
16.
Tumour Biol ; 37(6): 7525-34, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26684801

RESUMO

Radiation-induced necrosis (RN) is a relatively common side effect of radiation therapy for glioblastoma. However, the molecular mechanisms involved and the ways RN mechanisms differ from regulated cell death (apoptosis) are not well understood. Here, we compare the molecular mechanism of cell death (apoptosis or necrosis) of C6 glioma cells in both in vitro and in vivo (C6 othotopically allograft) models in response to low and high doses of X-ray radiation. Lower radiation doses were used to induce apoptosis, while high-dose levels were chosen to induce radiation necrosis. Our results demonstrate that active caspase-8 in this complex I induces apoptosis in response to low-dose radiation and inhibits necrosis by cleaving RIP1 and RI. When activation of caspase-8 was reduced at high doses of X-ray radiation, the RIP1/RIP3 necrosome complex II is formed. These complexes induce necrosis through the caspase-3-independent pathway mediated by calpain, cathepsin B/D, and apoptosis-inducing factor (AIF). AIF has a dual role in apoptosis and necrosis. At high doses, AIF promotes chromatinolysis and necrosis by interacting with histone H2AX. In addition, NF-κB, STAT-3, and HIF-1 play a crucial role in radiation-induced inflammatory responses embedded in a complex inflammatory network. Analysis of inflammatory markers in matched plasma and cerebrospinal fluid (CSF) isolated from in vivo specimens demonstrated the upregulation of chemokines and cytokines during the necrosis phase. Using RIP1/RIP3 kinase specific inhibitors (Nec-1, GSK'872), we also establish that the RIP1-RIP3 complex regulates programmed necrosis after either high-dose radiation or TNF-α-induced necrosis requires RIP1 and RIP3 kinases. Overall, our data shed new light on the relationship between RIP1/RIP3-mediated programmed necrosis and AIF-mediated caspase-independent programmed necrosis in glioblastoma.


Assuntos
Raios gama/efeitos adversos , Glioblastoma/radioterapia , Necrose/metabolismo , Necrose/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Lesões por Radiação/metabolismo , Lesões por Radiação/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/metabolismo , Western Blotting , Caspases , Proliferação de Células , Glioblastoma/metabolismo , Glioblastoma/patologia , Técnicas Imunoenzimáticas , Masculino , Necrose/etiologia , Lesões por Radiação/etiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Cancer Growth Metastasis ; 8: 51-60, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26648752

RESUMO

Glioblastoma (GB) is the most common malignant brain tumor. Drug resistance frequently develops in these tumors during chemotherapy. Therefore, predicting drug response in these patients remains a major challenge in the clinic. Thus, to improve the clinical outcome, more effective and tolerable combination treatment strategies are needed. Robust experimental evidence has shown that the main reason for failure of treatments is signal redundancy due to coactivation of several functionally linked receptor tyrosine kinases (RTKs), including anaplastic lymphoma kinase (ALK), c-Met (hepatocyte growth factor receptor), and oncogenic c-ros oncogene1 (ROS1: RTK class orphan) fusion kinase FIG (fused in GB)-ROS1. As such, these could be attractive targets for GB therapy. The study subjects consisted of 19 patients who underwent neurosurgical resection of GB tissues. Our in vitro and ex vivo models promisingly demonstrated that treatments with crizotinib (PF-02341066: dual ALK/c-Met inhibitor) and temozolomide in combination induced synergistic antitumor activity on FIG-ROS1-positive GB cells. Our results also showed that ex vivo FIG-ROS1+ slices (obtained from GB patients) when cultured were able to preserve tissue architecture, cell viability, and global gene-expression profiles for up to 14 days. Both in vitro and ex vivo studies indicated that combination blockade of FIG, p-ROS1, p-ALK, and p-Met augmented apoptosis, which mechanistically involves activation of Bim and inhibition of survivin, p-Akt, and Mcl-1 expression. However, it is important to note that we did not see any significant synergistic effect of crizotinib and temozolomide on FIG-ROS1-negative GB cells. Thus, these ex vivo culture results will have a significant impact on patient selection for clinical trials and in predicting response to crizotinib and temozolomide therapy. Further studies in different animal models of FIG-ROS1-positive GB cells are warranted to determine useful therapies for the management of human GBs.

18.
Tumour Biol ; 36(9): 7027-34, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25864108

RESUMO

Recurrent meningiomas constitute an uncommon but significant problem after standard (surgery and radiation) therapy failure. Current chemotherapies (hydroxyurea, RU-486, and interferon-α) are only of marginal benefit. There is an urgent need for more effective treatments for meningioma patients who have failed surgery and radiation therapy. Limonin, Tangeritin, Zerumbone, 6-Gingerol, Ganoderic Acid A, and Ganoderic Acid DM are some of the plant derivatives that have anti-tumorgenic properties and cause cell death in meningioma cells in vitro. Due to its ease of administration, long-term tolerability, and low incidence of long-term side effects, we explored its potential as a therapeutic agent against meningiomas by examining their efficacy in vitro against meningioma cells. Treatment effects were assessed using MTT assay, Western blot analysis, caspases assay, and DNA fragmentation assay. Results indicated that treatments of IOMM-Lee and CH157MN meningioma cells with Limonin, Tangeritin, Zerumbone, 6-Gingerol, Ganoderic Acid A, and Ganoderic Acid DM induced apoptosis with enhanced phosphorylation of glycogen synthase kinase 3 ß (GSK3ß) via inhibition of the Wnt5/ß-catenin pathway. These drugs did not induce apoptosis in normal human neurons. Other events in apoptosis included downregulation of tetraspanin protein (TSPAN12), survival proteins (Bcl-XL and Mcl-1), and overexpression apoptotic factors (Bax and caspase-3). These results provide preliminary strong evidence that medicinal plants containing Limonin, Tangeritin, 6-Gingerol, Zerumbone, Ganoderic Acid A, and Ganoderic Acid DM can be applied to high-grade meningiomas as a therapeutic agent, and suggests that further in vivo studies are necessary to explore its potential as a therapeutic agent against malignant meningiomas.


Assuntos
Catecóis/administração & dosagem , Álcoois Graxos/administração & dosagem , Flavonas/administração & dosagem , Ácidos Heptanoicos/administração & dosagem , Lanosterol/análogos & derivados , Limoninas/administração & dosagem , Meningioma/tratamento farmacológico , Sesquiterpenos/administração & dosagem , Triterpenos/administração & dosagem , Apoptose/efeitos dos fármacos , Catecóis/química , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Álcoois Graxos/química , Flavonas/química , Quinase 3 da Glicogênio Sintase/biossíntese , Quinase 3 da Glicogênio Sintase/genética , Glicogênio Sintase Quinase 3 beta , Ácidos Heptanoicos/química , Humanos , Lanosterol/administração & dosagem , Lanosterol/química , Limoninas/química , Meningioma/genética , Meningioma/patologia , Sesquiterpenos/química , Triterpenos/química , Via de Sinalização Wnt/efeitos dos fármacos
19.
Anticancer Res ; 35(2): 615-25, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25667438

RESUMO

Glioblastoma is the most common and deadliest of malignant primary brain tumors (Grade IV astrocytoma) in adults. Current standard treatments have been improving but patient prognosis still remains unacceptably devastating. Glioblastoma recurrence is linked to epigenetic mechanisms and cellular pathways. Thus, greater knowledge of the cellular, genetic and epigenetic origin of glioblastoma is the key for advancing glioblastoma treatment. One rapidly growing field of treatment, epigenetic modifiers; histone deacetylase inhibitors (HDACis), has now shown much promise for improving patient outcomes through regulation of the acetylation states of histone proteins (a form of epigenetic modulation) and other non-histone protein targets. HDAC inhibitors have been shown, in a pre-clinical setting, to be effective anticancer agents via multiple mechanisms, by up-regulating expression of tumor suppressor genes, inhibiting oncogenes, inhibiting tumor angiogenesis and up-regulating the immune system. There are many HDAC inhibitors that are currently in pre-clinical and clinical stages of investigation for various types of cancers. This review will explain the theory of epigenetic cancer therapy, identify HDAC inhibitors that are being investigated for glioblastoma therapy, explain the mechanisms of therapeutic effects as demonstrated by pre-clinical and clinical studies and describe the current status of development of these drugs as they pertain to glioblastoma therapy.


Assuntos
Epigênese Genética , Glioblastoma/tratamento farmacológico , Inibidores de Histona Desacetilases/uso terapêutico , Benzamidas/uso terapêutico , Ácidos Graxos/uso terapêutico , Humanos , Ácidos Hidroxâmicos/uso terapêutico , Oligopeptídeos/uso terapêutico
20.
Artigo em Inglês | MEDLINE | ID: mdl-25485306

RESUMO

Meningiomas are by far the most common tumors arising from the meninges. A myriad of aberrant signaling pathways involved with meningioma tumorigenesis, have been discovered. Understanding these disrupted pathways will aid in deciphering the relationship between various genetic changes and their downstream effects on meningioma pathogenesis. An understanding of the genetic and molecular profile of meningioma would provide a valuable first step towards developing more effective treatments for this intracranial tumor. Chromosomes 1, 10, 14, 22, their associated genes, and other potential targets have been linked to meningioma proliferation and progression. It is presumed that through an understanding of these genetic factors, more educated meningioma treatment techniques can be implemented. Future therapies will include combinations of targeted molecular agents including gene therapy, si-RNA mediation, proton therapy, and other approaches as a result of continued progress in the understanding of genetic and biological changes associated with meningiomas. This review provides an overview of the current knowledge of the genetic, signaling and molecular profile of meningioma and possible treatments strategies associated with such profiles.

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