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1.
Oncol Lett ; 17(6): 4843-4850, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31186691

RESUMO

Regulation of the host immune response serves a pivotal role in the persistence and progression of malignant glioma. To date, cytotoxic cluster of differentiation (CD)-8+ T and natural killer cells are considered the main cellular components of host tumor control. The influence of macrophages in an orthotropic C6 tumor implantation model was investigated and the aim of the present study was to characterize the effects of systemic macrophage-activation on glioma growth by using the granulocyte macrophage colony stimulating factor (rhGM-CSF). A total of 20 male Sprague-Dawley rats were orthotopically implanted with C6 glioma spheroids and treated subcutaneously with 10 µg/kg rhGM-CSF every other day; 9 animals served as controls. Serial magnetic resonance imaging was performed on days 7, 14, 21, 28, 32 and 42 post-implantation to monitor tumor volume. Histological work-up included hematoxylin and eosin, CD68/ED-1 macrophage, CD8 T-cell and Ki-67 MIB1 proliferation staining in gliomas and spleen. Experimental C6-gliomas developed in 15/20 (75%) animals. In rhGM-CSF treated rats, tumors developed significantly later and reached a smaller size (median, 134 mm3) compared with the controls (median, 262 mm3). On day 14, solid tumors presented in 11/17 (65%) rhGM-CSF-treated animals; in control animals tumor growth was detected in 3/9 animals on day 7 and in all animals on day 14. The mean survival time was 35 days in the rhGM-CSF group and significantly longer when compared with the control group (24 days). Immunohistochemistry exhibited significantly more macrophages in tumors, particularly in the perivascular zone of the rhGM-CSF group when compared with untreated animals; intratumoral CD8+ counts were equal in both groups. A systemic stimulation of macrophages by rhGM-CSF resulted in significantly reduced and delayed tumor growth in the rodent C6 glioma model. The present data suggested a significant role of macrophages in host control of experimental gliomas on the innate immune response. Until now, the role of macrophages may have been underestimated in host glioma control.

2.
World Neurosurg ; 129: e114-e127, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31100515

RESUMO

OBJECTIVE: Outcome in vestibular schwannoma (VS) surgery has improved enormously over the last decades. Surgical positioning remains a matter of discussion. A standardized protocol for diagnostics and management has been applied and evaluated for complications and functional outcome. METHODS: We examined 502 VS tumors in 483 patients (227 men and 256 women) between 2005 and 2016. According to our patient selection and treatment algorithm, 488 operations (97%) were performed in the semi-sitting position, and 14 (3%) were in the supine position. Auditory and facial functions were analyzed before and after surgery as were perioperative complications. RESULTS: There were 182 patients (36%) with small tumors (Hannover classification T1-T3A) and 320 (64%) large tumors (T3B or T4). Of the patients, 14% were neurofibromatosis type 2 cases. Complete tumor resection was achieved in 96.4%. Hearing preservation occurred in 44% of patients with small tumors and 23% of those with large tumors (Hannover classification), and correlated significantly with tumor size (P < 0.001). Facial palsy (House Brackmann grades II-VI) was present in 63 patients before and in 185 patients after surgery. Useful facial function (House Brackmann grades I-III) early after surgery was maintained in 86% of patients with small tumors and in 77% of patients with large tumors. Intraoperative complications included air embolism in 45 cases (9%), sinus injury in 3 cases, cerebrospinal fluid leakage in 46 cases (9%), and local hemorrhage in 19 cases (4%). Surgical revision was indicated in 31 cases (6%). CONCLUSIONS: In a standardized setting, the semi-sitting position allowed a safe approach. This setting offers the advantage of bimanual tumor nerve handling by the surgeon and an optimal visualization of important functional structures.


Assuntos
Neuroma Acústico/cirurgia , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias/epidemiologia , Recuperação de Função Fisiológica , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Posicionamento do Paciente , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
3.
BMC Med Imaging ; 16: 30, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27094510

RESUMO

BACKGROUND: Mobile 3D fluoroscopes have become increasingly available in neurosurgical operating rooms. In this series, the image quality and value of intraoperative 3D fluoroscopy with intravenous contrast agent for the evaluation of aneurysm occlusion and vessel patency after clip placement was assessed in patients who underwent surgery for intracranial aneurysms. MATERIALS AND METHODS: Twelve patients were included in this retrospective analysis. Prior to surgery, a 360° rotational fluoroscopy scan was performed without contrast agent followed by another scan with 50 ml of intravenous iodine contrast agent. The image files of both scans were transferred to an Apple PowerMac® workstation, subtracted and reconstructed using OsiriX® free software. The procedure was repeated after clip placement. Both image sets were compared for assessment of aneurysm occlusion and vessel patency. RESULTS: Image acquisition and contrast administration caused no adverse effects. Image quality was sufficient to follow the patency of the vessels distal to the clip. Metal artifacts reduce the assessability of the immediate vicinity of the clip. Precise image subtraction and post-processing can reduce metal artifacts and make the clip-site assessable and depict larger neck-remnants. CONCLUSION: This technique quickly supplies images at adequate quality to evaluate distal vessel patency after aneurysm clipping. Significant aneurysm remnants may be depicted as well. As it does not require visual control of all vessels that are supposed to be evaluated intraoperatively, this technique may be complementary to other intraoperative tools like indocyanine green videoangiography and micro-Doppler, especially for the assessment of larger aneurysms. At the momentary state of this technology, it cannot replace postoperative conventional angiography. However, 3D fluoroscopy and image post-processing are young technologies. Further technical developments are likely to result in improved image quality.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/cirurgia , Procedimentos Neurocirúrgicos/métodos , Meios de Contraste/administração & dosagem , Estudos de Viabilidade , Fluoroscopia/instrumentação , Humanos , Interpretação de Imagem Assistida por Computador/normas , Procedimentos Neurocirúrgicos/instrumentação , Estudos Retrospectivos , Software
4.
BMC Cancer ; 16: 115, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26883117

RESUMO

BACKGROUND: Medulloblastoma is the most common malignant brain tumor in children and can be divided in different molecular subgroups. Patients whose tumor is classified as a Group 3 tumor have a dismal prognosis. However only very few tumor models are available for this subgroup. METHODS: We established a robust orthotopic xenograft model with a cell line derived from the malignant pleural effusions of a child suffering from a Group 3 medulloblastoma. RESULTS: Besides classical characteristics of this tumor subgroup, the cells display cancer stem cell characteristics including neurosphere formation, multilineage differentiation, CD133/CD15 expression, high ALDH-activity and high tumorigenicity in immunocompromised mice with xenografts exactly recapitulating the original tumor architecture. CONCLUSIONS: This model using unmanipulated, human medulloblastoma cells will enable translational research, specifically focused on Group 3 medulloblastoma.


Assuntos
Meduloblastoma/patologia , Neoplasias Experimentais/patologia , Animais , Biomarcadores Tumorais , Linhagem Celular Tumoral , Feminino , Humanos , Lactente , Masculino , Camundongos , Camundongos SCID , Células-Tronco Neoplásicas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Neurosurgery ; 78(2): 265-73, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26421589

RESUMO

BACKGROUND: Early detection of vasospasm (VS) following aneurysmal subarachnoid hemorrhage (aSAH) is vital to trigger therapy and to prevent infarction and subsequent permanent neurological deficit. Although motor evoked potentials (MEPs) are a well-established method for intraoperative detection of cerebral VS and cerebral ischemia during aneurysm surgery, there are no studies investigating the diagnostic value of MEPs for detecting delayed VS following aSAH in an intensive care unit. OBJECTIVE: A prospective study was conceived to assess the diagnostic accuracy of MEPs in comparison with digital subtraction angiography. METHODS: MEP threshold changes were determined in patients both with and without angiographic VS following high-grade aSAHs. Sensitivity, specificity, and the positive and negative predictive values of significant MEP threshold increases, which indicate angiographic VS, were calculated. RESULTS: In all patients experiencing VS of the arteries supplying cerebral motor areas, a minimal MEP threshold increase of 50 mA (mean 66.25 mA) was observed, whereas a maximum MEP threshold increase of 30 mA was observed in patients without VS. Therefore, an increase from a baseline of ≥50 mA was considered significant and resulted in a sensitivity of 0.83, a specificity of 0.92, a positive predictive value of 0.83, and a negative predictive value of 0.92. CONCLUSION: VS following aSAH can be detected accurately by using MEPs. MEPs are a feasible bedside tool for online VS detection in an intensive care unit and, therefore, may complement existing diagnostic tools.


Assuntos
Potencial Evocado Motor/fisiologia , Hemorragia Subaracnóidea/diagnóstico , Hemorragia Subaracnóidea/fisiopatologia , Vasoespasmo Intracraniano/diagnóstico , Vasoespasmo Intracraniano/fisiopatologia , Adulto , Angiografia Digital/métodos , Feminino , Humanos , Unidades de Terapia Intensiva/tendências , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Hemorragia Subaracnóidea/complicações , Vasoconstrição/fisiologia , Vasoespasmo Intracraniano/etiologia
6.
J Neurol Surg Rep ; 76(1): e128-34, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26251789

RESUMO

Primary intramedullary spinal glioblastoma multiforme (sGBM) with a secondary cerebral manifestation is a very rare entity with a poor outcome. Case studies show a mean average of survival of 10 months after diagnosis. These tumors tend to develop at a young age. A combination with an arteriovenous malformation in the same location has never been published before. Vascular malformations in association with cerebral glioblastomas have only been reported in five cases so far. Proangiogenic factors are assumed to be involved in the appearance of both entities. We present a case study and a review of the literature.

7.
J Mol Psychiatry ; 3(1): 5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26019867

RESUMO

In the last decade evidence has accumulated that suggests that the cerebellum is involved not only in motor but also in behavioral and cognitive functions. A myriad of anatomical, clinical and imaging studies support that assumption. The lengthened survival of patients with cerebellar tumors has also brought an increased awareness of neurocognitive deficits to the neurooncological community. Although evidence from neurosurgical case series exists that clearly demonstrates that patients afflicted from posterior fossa tumors are at high risk for long-term cognitive or adaptive deficits, there is still a lack of systematic translational review on this issue. Accordingly a systematic review was conducted to summarize the impact of cerebellar lesions on behavior and cognition. The findings and clinical implications are discussed in the light of the recent advances in neuroimaging techniques.

8.
Neurosurgery ; 11 Suppl 2: 119-26; discussion 126, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25599196

RESUMO

BACKGROUND: Intraoperative imaging of cerebral aneurysms may be desirable in emergency situations with large space-occupying hematomas or to visualize vessels after clip placement. Mobile 3-dimensional fluoroscopes are available in a number of neurosurgical departments and may be useful in combination with simple image postprocessing to depict cerebral vessels. OBJECTIVE: To assess whether intracranial aneurysms are detectable with appropriate image quality with intraoperative 3-dimensional fluoroscopy with intravenous contrast administration. METHODS: Eight patients were included in the study. The patients' heads were fixed in a radiolucent Mayfield clamp. First, a rotational fluoroscopy scan was performed without contrast agent. Then, a second scan with 50 mL iodine contrast agent was performed. The DICOM (digital imaging and communications in medicine) data of both scans were transferred to an Apple PowerMac workstation, subtracted, and reconstructed with OsiriX imaging software. The images were compared with preoperative angiograms. RESULTS: No adverse effects were observed during contrast administration. The entire procedure from fluoroscope positioning to the production of usable 3-dimensional images took 5 to 6 minutes with an image acquisition time of 2 × 24 seconds. The configuration of the aneurysm and the vessel anatomy were assessable. Previous coiling limited image quality in 1 patient. CONCLUSION: This technique quickly provides images of adequate quality to assess the configuration of intracranial aneurysms, which may be helpful when immediate intraoperative information about intracranial vessel pathologies is required. The positioning of the fluoroscope, image acquisition, and processing can be completely integrated into the surgical workflow.


Assuntos
Angiografia Digital/métodos , Angiografia Cerebral/métodos , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Adulto , Idoso , Meios de Contraste , Estudos de Viabilidade , Feminino , Fluoroscopia , Humanos , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade , Software
9.
J Neurosurg ; 122(3): 692-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25526275

RESUMO

The most appropriate surgical technique for posterior fossa decompression in Chiari malformation (CM) remains a matter of debate. Intraoperative electrophysiological studies during posterior fossa decompression of Type I CM (CM-I) aim to shed light on the entity's pathomechanism as well as on the ideal extent of decompression. The existing reports on this issue state that significant improvement in conduction occurs after craniotomy in all cases, but additional durotomy contributes a further improvement in only a minority of cases. This implies that craniotomy alone might suffice for clinical improvement without the need of duraplasty or even subarachnoid manipulation at the level of the craniocervical junction. In contrast to published data, the authors describe the case of a 32-year-old woman who underwent surgery for CM associated with extensive cervicothoracic syringomyelia and whose intraoperative somatosensory evoked potentials (SSEPs) did not notably improve after craniotomy or following durotomy; rather, they only improved after opening of the fourth ventricle and restoration of CSF flow through the foramen of Magendie. Postoperatively, the patient recovered completely from her preoperative neurological deficits. To the authors' knowledge, this is the first report of significant SSEP recovery after opening the fourth ventricle in the decompression of a CM-I. The electrophysiological and operative techniques are described in detail and the findings are discussed in the light of available literature. The authors conclude that there might be a subset of CM-I patients who require subarachnoid dissection at the level of the craniocervical junction to benefit clinically. Prospective studies with detailed electrophysiological analyses seem warranted to answer the question regarding the best surgical approach in CM-I decompression.


Assuntos
Malformação de Arnold-Chiari/cirurgia , Fossa Craniana Posterior/cirurgia , Craniectomia Descompressiva/métodos , Potenciais Somatossensoriais Evocados , Quarto Ventrículo/cirurgia , Procedimentos Neurocirúrgicos/métodos , Adulto , Malformação de Arnold-Chiari/complicações , Circulação Cerebrovascular , Feminino , Humanos , Monitorização Intraoperatória , Cuidados Pós-Operatórios , Recuperação de Função Fisiológica , Siringomielia/complicações , Siringomielia/cirurgia
10.
Emerg Radiol ; 22(1): 97-100, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24989477

RESUMO

It was the objective of this report to present a case of recurrent aneurysmal subarachnoid hemorrhage (SAH) and intracerebral hemorrhage (ICH) in which an MCA aneurysm was detected by 3D rotational fluoroscopy in an emergency situation. A 44-year-old woman was admitted from an external department after repeated SAH and temporal ICH. Due to progressive anisocoria and cardiocirculatory instability, she was transferred to the operating room without angiography. After a 3D rotational fluoroscopy baseline scan, another scan with 50 ml of iodine contrast agent was performed. The Digital Imaging and Communications in Medicine (DICOM) data sets were subtracted and reconstructed using the OsiriX® free imaging software. No adverse effect was observed during and after the administration of the contrast agent. The entire procedure from positioning of the fluoroscope to the production of utilizable 3D images was completely integrated into the surgical workflow with an image acquisition time of 2 × 24 s. The configuration of the aneurysm, the aneurysm-carrying vessel, and the distal vessel anatomy were well assessable. This technique quickly supplies images at adequate quality to assess the configuration of an intracranial aneurysm and is a useful diagnostic tool if the patient's critical condition prohibits aneurysm diagnostics by angiography or CT angiography.


Assuntos
Imageamento Tridimensional , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Cuidados Intraoperatórios , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/cirurgia , Adulto , Meios de Contraste , Feminino , Fluoroscopia , Humanos , Interpretação de Imagem Assistida por Computador , Artéria Cerebral Média , Recidiva
11.
BMC Res Notes ; 7: 496, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-25099491

RESUMO

BACKGROUND: Glioblastoma multiforme located in the posterior fossa is extremely rare with a frequency up to 3.4%. Compared with glioblastoma of the hemispheres the prognosis of infratentorial glioblastoma seems to be slightly better. Absence of brainstem invasion and low expression rates of epidermal growth factor receptor are described as factors for long-time survival due to the higher radiosensitivity of these tumors. CASE PRESENTATION: In this case study, we report a German female patient with an exophytic glioblastoma multiforme arising from the cerebellar tonsil and a secondary spinal manifestation. Furthermore, the tumor showed no O (6)-Methylguanine-DNA methyltransferase promotor-hypermethylation and no isocitrate dehydrogenase 1 mutations. All these signs are accompanied by significantly shorter median overall survival. A long-term tumor control of the spinal metastases was achieved by a combined temozolomide/bevacizumab and irradiation therapy, as part of a standard care administered by the treating physician team. CONCLUSION: To our knowledge this is the first published case of a combined cerebellar exophytic glioblastoma with a subsequent solid spinal manifestation. Furthermore this case demonstrates a benefit undergoing this special adjuvant therapy regime in terms of overall survival. Due to the limited overall prognosis of the disease, spinal manifestations of glioma are rarely clinically relevant. The results of our instructive case, however, with a positive effect on both life quality and survival warrant treating future patients in the frame of a prospective clinical study.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Glioblastoma/tratamento farmacológico , Neoplasias da Coluna Vertebral/secundário , Bevacizumab , Eletromiografia , Feminino , Glioblastoma/patologia , Glioblastoma/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neoplasias da Coluna Vertebral/patologia , Neoplasias da Coluna Vertebral/fisiopatologia
12.
BMC Res Notes ; 7: 159, 2014 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-24642114

RESUMO

BACKGROUND: The human endogenous retrovirus K (HERV-K) has been acquired by the genome of human ancestors million years ago. It is the most complete of the HERVs with transcriptionally active gag, pol and env genes. Splice variants of env, which are rec, 1.5 kb transcript and Np9 have been suggested to be tumorigenic. Transcripts of HERV-K have been detected in a multitude of human cancers. However, no such reports are available concerning glioblastomas (GBM), the most common malignant brain tumor in adults. Patients have a limited prognosis of 14.6 months in median, despite standard treatment. Therefore, we elucidated whether HERV-K transcripts could be detected in these tumors and serve as new molecular target for treatment. FINDINGS: We analyzed human GBM cell lines, tissue samples from patients and primary cell cultures of different passages for HERV-K full length mRNA and env, rec and 1.5 kb transcripts. While the GBM cell lines U138, U251, U343 and GaMG displayed weak and U87 strong expression of the full length HERV-K, the splice products could not be detected, despite a weak expression of env mRNA in U87 cells. Very few tissue samples from patients showed weak expression of env mRNA, but none of the rec or 1.5 kb transcripts. Primary cells expressed the 1.5 kb transcript weakly in early passages, but lost HERV-K expression with extended culture time. CONCLUSIONS: These data suggest that HERV-K splice products do not play a role in human malignant gliomas and therefore, are not suitable as targets for new therapy regimen.


Assuntos
Neoplasias Encefálicas/genética , Retrovirus Endógenos/genética , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Glioblastoma/genética , Adulto , Idoso , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/virologia , Linhagem Celular Tumoral , Glioblastoma/patologia , Glioblastoma/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Splicing de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Células Tumorais Cultivadas
13.
Neurocrit Care ; 20(3): 406-12, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23982597

RESUMO

INTRODUCTION: This study was conducted to prospectively evaluate the diagnostic value of detailed neurological evaluation, transcranial Doppler sonography (TCD) and Perfusion-CT (PCT) to predict delayed vasospasm (DV) and delayed cerebral infarction (DCI) within the following 3 days in patients with aneurysmal subarachnoid hemorrhage (SAH). METHODS: A total of 61 patients with aneurysmal SAH were included in the study. All patients were amenable for neurological evaluation throughout the critical phase to develop secondary ischemia after SAH. The neurological status was assessed three times a day according to a detailed examination protocol. Mean flow velocities (MFV) in intracranial vessel trunks were measured daily by TCD. Native CT and PCT were routinely acquired at 3-day intervals and, in addition, whenever it was thought to be of diagnostic relevance. The predictive values of abnormal PCT and accelerations in TCD (MFV > 140 cm/s) to detect angiographic DV and DCI within the following 2 days were calculated and compared to the predictive value of delayed ischemic neurological deficits (DIND). RESULTS: The accuracy of TCD and PCT to predict DV or DCI was 0.65 and 0.63, respectively. In comparison, DIND predicted DV or DCI with an accuracy of 0.96. Pathological PCT findings had a higher sensitivity (0.93) and negative predictive value (0.98) than TCD (0.81 and 0.96). CONCLUSION: Neurological assessment at close intervals is the most accurate parameter to detect DV and DCI in the following 3 days. However, DIND may not be reversible. The routine acquisition of PCT in addition to daily TCD examinations seems reasonable, particularly in patients who are not amenable to a detailed neurological examination since it has a higher sensitivity and negative predictive value than TCD and leaves a lower number of undetected cases of vasospasm and infarction.


Assuntos
Isquemia Encefálica/diagnóstico , Isquemia Encefálica/etiologia , Imagem Multimodal/métodos , Imagem Multimodal/normas , Hemorragia Subaracnóidea/complicações , Angiografia Digital , Angiografia Cerebral , Feminino , Humanos , Masculino , Exame Neurológico/métodos , Imagem de Perfusão/métodos , Imagem de Perfusão/normas , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas , Ultrassonografia Doppler Transcraniana/métodos , Ultrassonografia Doppler Transcraniana/normas , Vasoespasmo Intracraniano/diagnóstico , Vasoespasmo Intracraniano/etiologia
14.
Neuro Oncol ; 15(12): 1696-709, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24220141

RESUMO

BACKGROUND: Metastasis-associated in colon cancer 1 (MACC1) has been established as an independent prognostic indicator of metastasis formation and metastasis-free survival for patients with colon cancer and other solid tumors. However, no data are available concerning MACC1 expression in human astrocytic tumors. Glioblastoma multiforme (GBM) is the most prevalent primary brain tumor of adulthood, and due to its invasive and rapid growth, patients have unfavorable prognoses. Although these tumors rarely metastasize, their invasive and migratory behavior is similar to those of metastatic cells of tumors of different origin. Thus, we hypothesized that MACC1 may be involved in progression of human gliomas. METHODS: We performed real-time measurements of proliferation and migration in MACC1-transfected GBM cell lines (U138, U251) and evaluated tumor formation in organotypic hippocampal slice cultures of mice. Semiquantitative and quantitative real-time reverse transcription PCR analyses were performed for MACC1 and for its transcriptional target c-Met in human astrocytoma of World Health Organization grade II (low-grade astrocytoma) and GBM biopsies. Data were validated by MACC1 immunohistochemistry in independent matched samples of low-grade astrocytoma and GBM. RESULTS: MACC1 increases the proliferative, migratory, and tumor-formation abilities of GBM cells. The c-Met inhibitor crizotinib reduced MACC1-induced migration and tumor formation in organotypic hippocampal slice cultures of mice. Analyzing patients' biopsies, MACC1 expression increased concomitantly with increasing World Health Organization grade. Moreover, MACC1 expression levels allowed discrimination of dormant and recurrent low-grade astrocytomas and of primary and secondary GBM. Strong MACC1 expression correlated with reduced patient survival. CONCLUSIONS: MACC1 may represent a promising biomarker for prognostication and a new target for treatment of human gliomas.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Fatores de Transcrição/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose , Biomarcadores Tumorais/genética , Western Blotting , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Movimento Celular , Proliferação de Células , Criança , Pré-Escolar , Progressão da Doença , Feminino , Citometria de Fluxo , Seguimentos , Glioma/metabolismo , Glioma/mortalidade , Humanos , Técnicas Imunoenzimáticas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Gradação de Tumores , Técnicas de Cultura de Órgãos , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Transativadores , Fatores de Transcrição/genética , Células Tumorais Cultivadas , Adulto Jovem
15.
Bioorg Med Chem ; 21(13): 3949-57, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23706268

RESUMO

HIF-1α regulated genes are mainly responsible for tumour resistance to radiation- and chemo-therapy. Among these genes, carbonic anhydrase isoform IX (CA9) is highly over expressed in many types of cancer especially in high grade brain cancer like Glioblastoma (GBM). Inhibition of the enzymatic activity by application of specific chemical CA9 inhibitor sulphonamides (CAI) like Acetazolamide (Aza.), the new sulfonamide derivative carbonic anhydrase inhibitor (SU.D2) or indirect inhibitors like the HIF-1α inhibitor Chetomin or molecular inhibitors like CA9-siRNA are leading to an inhibition of the functional role of CA9 during tumorigenesis. Human GBM cells were treated with in vitro hypoxia (1, 6, or 24 h at 0.1%, O2). Aza. application was at a range between 250 and 8000 nM and the HIF-1α inhibitor Chetomin at a concentration range of 150-500 nM. Cell culture plates were incubated for 24 h under hypoxia (0.1% O2). Further, CA9-siRNA constructs were transiently transfected into GBM cells exposed to extreme hypoxic aeration conditions. CA9 protein expression level was detectable in a cell-type specific manner under normoxic conditions. Whereas U87-MG exhibited a strong aerobic expression, U251 and U373 displayed moderate and GaMG very weak normoxic CA9 protein bands. Aza. as well as SU.D2 displayed inhibitory characteristics to hypoxia induced CA9 expression in the four GBM cell lines for 24 h of hypoxia (0.1% O2) at concentrations between 3500 and 8000 nM, on both the protein and mRNA level. Parallel experiments using CA9-siRNA confirmed these results. Application of 150-500 nM of the glycolysis inhibitor Chetomin under similar oxygenation conditions led to a sharply reduced expression of both CA IX protein and CA9 mRNA levels, indicating a clear glucose availability involvement for the hypoxic HIF-1α and CA9 expression in GBM cells. Hypoxia significantly influences the behaviour of human tumour cells by activation of genes involved in the adaptation to hypoxic stress. The main objective in malignant GBM therapy is either to eradicate the tumour or to convert it into a controlled, quiescent chronic disease. Aza., SU.D2, Chetomin or CA9-siRNA possesses functional CA9 inhibitory characteristics when applied against human cancers with hypoxic regions like GBM. They may be used as alternative or in conjunction with other direct inhibitors possessing similar functionality, thereby rendering them as potential optimal tools for the development of an optimized therapy in human brain cancer treatment.


Assuntos
Acetazolamida/química , Acetazolamida/farmacologia , Antígenos de Neoplasias/metabolismo , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Sulfonamidas/química , Sulfonamidas/farmacologia , Antígenos de Neoplasias/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/enzimologia , Anidrase Carbônica IX , Anidrases Carbônicas/genética , Hipóxia Celular , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/enzimologia , Humanos , Modelos Moleculares , RNA Mensageiro/genética , RNA Interferente Pequeno/genética
16.
Exp Transl Stroke Med ; 5(1): 6, 2013 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-23618347

RESUMO

This article reviews experimental and clinical data on the use of magnesium as a neuroprotective agent in various conditions of cerebral ischemia. Whereas magnesium has shown neuroprotective properties in animal models of global and focal cerebral ischemia, this effect could not be reproduced in a large human stroke trial. These conflicting results may be explained by the timing of treatment. While treatment can be started before or early after ischemia in experimental studies, there is an inevitable delay of treatment in human stroke. Magnesium administration to women at risk for preterm birth has been investigated in several randomized controlled trials and was found to reduce the risk of neurological deficits for the premature infant. Postnatal administration of magnesium to babies after perinatal asphyxia has been studied in a number of controlled clinical trials. The results are promising but the trials have, so far, been underpowered. In aneurysmal subarachnoid hemorrhage (SAH), cerebral ischemia arises with the onset of delayed cerebral vasospasm several days after aneurysm rupture. Similar to perinatal asphyxia in impending preterm delivery, treatment can be started prior to ischemia. The results of clinical trials are conflicting. Several clinical trials did not show an additive effect of magnesium with nimodipine, another calcium antagonist which is routinely administered to SAH patients in many centers. Other trials found a protective effect after magnesium therapy. Thus, it may still be a promising substance in the treatment of secondary cerebral ischemia after aneurysmal SAH. Future prospects of magnesium therapy are discussed.

17.
J Neurol Surg A Cent Eur Neurosurg ; 74(4): 262-4, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22777924

RESUMO

Exophytic glioblastoma arising from the cerebellar tonsil is an extremely rare variant within the possible anatomical presentations of the glioblastoma multiforme (GBM). We report the case of a 55-year-old woman who presented with a tumor located at the cranio-cervical junction with compression of the medulla oblongata and consecutive hydrocephalus. Due to the radiological presentation, the first tentative diagnosis was a meningioma. The tumor was microsurgically removed. Histopathological examination of the tumor revealed a GBM WHO IV. The patient underwent a postoperative percutaneous radiotherapy and concomitant chemotherapy with temozolomide. GBM should be also considered in the differential diagnosis of cerebellar tumors.


Assuntos
Neoplasias Cerebelares/cirurgia , Glioblastoma/cirurgia , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/terapia , Quimiorradioterapia , Craniotomia , Feminino , Glioblastoma/patologia , Glioblastoma/terapia , Humanos , Hidrocefalia/etiologia , Imageamento por Ressonância Magnética , Bulbo/patologia , Pessoa de Meia-Idade , Inclusão em Parafina , Fixação de Tecidos , Resultado do Tratamento
18.
Radiol Res Pract ; 2012: 231206, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23050146

RESUMO

Background. If detected in time, delayed cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) may be treated by balloon angioplasty or chemical vasospasmolysis in order to enhance cerebral blood flow (CBF) and protect the brain from ischemic damage. This study was conceived to compare the diagnostic accuracy of detailed neurological examination, Transcranial Doppler Sonography (TCD), and Perfusion-CT (PCT) to detect angiographic vasospasm. Methods. The sensitivity, specificity, positive and negative predictive values of delayed ischemic neurological deterioration (DIND), pathological findings on PCT-maps, and accelerations of the mean flow velocity (MVF) were calculated. Results. The accuracy of DIND to predict angiographic vasospasm was 0.88. An acceleration of MFV in TCD (>140 cm/s) had an accuracy of 0.64, positive PCT-findings of 0.69 with a higher sensitivity, and negative predictive value than TCD. Interpretation. Neurological assessment at close intervals is the most sensitive and specific parameter for cerebral vasospasm. PCT has a higher accuracy, sensitivity and negative predictive value than TCD. If detailed neurological evaluation is possible, it should be the leading parameter in the management and treatment decisions. If patients are not amenable to detailed neurological examination, PCT at regular intervals is a helpful tool to diagnose secondary vasospasm after aneurysmal SAH.

19.
In Vivo ; 26(4): 571-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22773570

RESUMO

BACKGROUND: In glioblastoma multiforme (GBM), the serine protease urokinase plasminogen activator (uPA), and matrix metalloproteases (MMP-2/MMP-9) contribute to its invasive growth pattern, which is the major obstacle to successful surgical treatment. MATERIALS AND METHODS: The expression of uPA was determined in monolayers and spheroids of the rodent GBM cell line C6 by immunohistochemistry and polymerase chain reaction (PCR). The longitudinal expression of proteases was studied in orthotopically implanted spheroids by semi-quantitative immunohistochemistry (IHC) in Sprague Dawley rats (n=40). The tumor volume was monitored by magnetic resonance imaging (MRI). RESULTS: In vitro, the GBM cell line C6 expresses high levels of uPA. In vivo, a continuous increase of uPA, uPA-receptor (uPAR), MMP-2, and MMP-9 expression was found in the infiltration zone. uPA was located exclusively in the infiltration zone and in the vascular basal layers. The mean tumor volume 23 days after implantation was 3.2 mm3. CONCLUSION: uPA, uPAR, MMP-2 and MMP-9 play an important role in GBM growth. Blockade of uPA and interruption of the proteolytic cascade could become a useful tool in the therapy of GBM.


Assuntos
Neoplasias Encefálicas/enzimologia , Glioblastoma/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Animais , Sequência de Bases , Neoplasias Encefálicas/patologia , Primers do DNA , Glioblastoma/patologia , Imuno-Histoquímica , Reação em Cadeia da Polimerase , Ratos
20.
World J Clin Oncol ; 3(5): 67-79, 2012 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-22582165

RESUMO

Glioblastomas are characterized by an aggressive local growth pattern, a marked degree of invasiveness and poor prognosis. Tumor invasiveness is facilitated by the increased activity of proteolytic enzymes which are involved in destruction of the extracellular matrix of the surrounding healthy brain tissue. Elevated levels of matrix metalloproteinases (MMPs) were found in glioblastoma (GBM) cell-lines, as well as in GBM biopsies as compared with low-grade astrocytoma (LGA) and normal brain samples, indicating a role in malignant progression. A careful review of the available literature revealed that both the expression and role of several of the 23 human MMP proteins is controversely discussed and for some there are no data available at all. We therefore screened a panel of 15 LGA and 15 GBM biopsy samples for those MMPs for which there is either no, very limited or even contradictory data available. Hence, this is the first complete compilation of the expression pattern of all 23 human MMPs in astrocytic tumors. This study will support a better understanding of the specific expression patterns and interaction of proteolytic enzymes in malignant human glioma and may provide additional starting points for targeted patient therapy.

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