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1.
J Neurooncol ; 126(2): 279-88, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26468137

RESUMO

MRI grading of grade II and III gliomas may have an important impact on treatment decisions. Occasionally,both conventional MRI (cMRI) and histology fail to clearly establish the tumour grade. Three cMRI features(no necrosis; no relevant oedema; absent or faint contrast enhancement) previously validated in 196 patients with supratentorial gliomas directed our selection of 68 suspected low-grade gliomas (LGG) that were also investigated by advanced MRI (aMRI), including perfusion weighted imaging (PWI), diffusion weighted imaging(DWI) and spectroscopy. All the gliomas had histopathological diagnoses. Sensitivity and specificity of cMRI preoperative diagnosis were 78.5 and 38.5 %, respectively, and 85.7 and 53.8 % when a MRI was included, respectively. ROC analysis showed that cut-off values of 1.29 for maximum rCBV, 1.69 for minimum rADC, 2.1 for rCho/Cr ratio could differentiate between LGG and HGG with a sensitivity of 61.5, 53.8, and 53.8 % and a specificity of 54.7, 43 and 64.3 %, respectively. A significantly longer OS was observed in patients with a maximum rCBV<1.46 and minimum rADC>1.69 (80 vs 55 months, p = 0.01; 80 vs 51 months, p = 0.002, respectively). This result was also confirmed when cases were stratified according to pathology (LGG vs HGG). The ability of a MRI to differentiate between LGG and HGG and to predict survival improved as the number of a MRI techniques considered increased. In a selected population of suspected LGG,classification by cMRI underestimated the actual fraction of HGG. aMRI slightly increased the diagnostic accuracy compared to histopathology. However, DWI and PWI were prognostic markers independent of histological grade.


Assuntos
Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Glioma/mortalidade , Glioma/patologia , Imageamento por Ressonância Magnética/métodos , Gradação de Tumores/métodos , Adulto , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Sensibilidade e Especificidade , Análise de Sobrevida
2.
Neurol Sci ; 37(10): 1727-30, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27329275

RESUMO

Medulloblastomas and high-grade gliomas (HGG) are two distinct brain tumor, with different peculiarities in terms of age of onset, localizations and prognosis. The coexistence of the two neoplasms in the same adult patient is an extremely rare event. We present the case of a woman treated with radio-chemotherapy for an HGG, who developed a cerebellar medulloblastoma 7 years later. Considering the poor prognosis of these tumors, the lack of knowledge about the mechanisms of onset as well as effective therapies, it is necessary to determine the exact role of irradiation and the presence of any potential molecular genetic abnormalities in the developing of the two tumors.


Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Cerebelares/secundário , Meduloblastoma/secundário , Oligodendroglioma/patologia , Adulto , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Neoplasias Cerebelares/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Meduloblastoma/diagnóstico por imagem , Oligodendroglioma/diagnóstico por imagem , Oligodendroglioma/terapia
3.
Neurol Sci ; 34(12): 2151-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23525755

RESUMO

Neoplastic meningitis (NM) is diagnosed in 1-2 % of patients with primary brain tumors. Standard treatment of NM includes single-agent or combination chemotherapy, with compounds such as methotrexate, thiotepa, and cytarabine (Ara-C) or its injectable, sustained-release formulation Depocyte(®). In this Report, we reported the data of efficacy and tolerability of an intrathecal Depocyte(®) regimen for patients presenting with NM from primary brain tumors. We described 12 patients with NM confirmed at magnetic resonance imaging (MRI) and with a positive cerebrospinal fluid (CSF) cytology. Patients were treated with repeated courses of intrathecal Depocyte(®) (once every 2 weeks for 1 month of induction therapy and as consolidation therapy on a monthly base in responding patients). Twelve patients (10 males and 2 females) were treated by our Institution. The diagnosis of primitive brain tumor was medulloblastoma in six patients, germinoma in two patients, pylocitic astrocytomas with spongioblastic aspects, teratocarcinoma, meningeal melanoma, and ependimoma in the other four patients. The total number of Depocyte(®) cycles ranged from one to nine. In 7/12 patients, there was clinical and/or radiological response after Depocyte(®), and the toxicity was moderate and transient, mainly due to the lumbar puncture procedure. In the two patients with germinoma, we observed a normalization of MRI Imaging and negativization of CSF with disappearance of the tumor cells. OS was 180 days (range 20-300, CI 95 %).


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/patologia , Citarabina/administração & dosagem , Neoplasias Meníngeas/tratamento farmacológico , Neoplasias Meníngeas/secundário , Meningite/tratamento farmacológico , Adulto , Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/complicações , Citarabina/uso terapêutico , Feminino , Humanos , Lipossomos , Masculino , Neoplasias Meníngeas/líquido cefalorraquidiano , Neoplasias Meníngeas/patologia , Meningite/líquido cefalorraquidiano , Meningite/etiologia , Meningite/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
4.
J Neurooncol ; 106(3): 595-600, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21874383

RESUMO

In 1991, a prospective phase II trial was initiated to evaluate the efficacy of treatment for adults with medulloblastoma (MB). After surgery, patients were staged with a neuroradiologic examination of the brain and neuroaxis and by cerebrospinal fluid cytology. All patients received three cycles of upfront cisplatinum (cisplatinum) and etoposide (VP16) chemotherapy followed by cranio-spinal radiation therapy. The current article reports on the long-term results from that trial. After a median follow-up of 14.9 years, among a total of 28 adults with MB, the overall progression-free survival and overall survival (OS) rates at 5 years were 57.6 and 80%, respectively. The median OS for the whole group of patients was 11.3 years. The observed toxicity was mainly hematological, with leukopenia and thrombocytopenia (16% of grades 3 and 4). In summary, in our small series of patients, the role of combination administration of CDDP + VP16 started before the initiation of radiotherapy in reducing recurrences, particularly distant recurrences, remains unclear. To know whether adding chemotherapy to craniospinal radiation in adult therapy increases relapse-free and overall survival, we must await the results of a larger randomized controlled clinical trial.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Cerebelares/tratamento farmacológico , Cisplatino/administração & dosagem , Etoposídeo/administração & dosagem , Meduloblastoma/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Cerebelares/mortalidade , Neoplasias Cerebelares/radioterapia , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Meduloblastoma/mortalidade , Meduloblastoma/radioterapia , Pessoa de Meia-Idade , Análise de Sobrevida
5.
Nat Med ; 6(4): 447-50, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10742153

RESUMO

Glioblastomas, the most frequent and malignant of primary brain tumors, have a very poor prognosis. Gene therapy of glioblastomas is limited by the short survival of viral vectors and by their difficulty in reaching glioblastoma cells infiltrating the brain parenchyma. Neural stem/progenitor cells can be engineered to produce therapeutic molecules and have the potential to overcome these limitations because they may travel along the white matter, like neoplastic cells, and engraft stably into the brain. Retrovirus-mediated transfer of the gene for interleukin-4 is an effective treatment for rat brain glioblastomas. Here, we transferred the gene for interleukin-4 into C57BL6J mouse primary neural progenitor cells and injected those cells into established syngeneic brain glioblastomas. This led to the survival of most tumor-bearing mice. We obtained similar results by implanting immortalized neural progenitor cells derived from Sprague-Dawley rats into C6 glioblastomas. We also documented by magnetic resonance imaging the progressive disappearance of large tumors, and detected 5-bromodeoxyuridine-labeled progenitor cells several weeks after the injection. These findings support a new approach for gene therapy of brain tumors, based on the grafting of neural stem cells producing therapeutic molecules.


Assuntos
Neoplasias Encefálicas/terapia , Terapia Genética , Glioblastoma/terapia , Transplante de Células-Tronco Hematopoéticas , Interleucina-4/genética , Neurônios/transplante , Animais , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Córtex Cerebral/citologia , Glioblastoma/patologia , Humanos , Interleucina-4/imunologia , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/citologia , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley
6.
Clin Neurol Neurosurg ; 207: 106808, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34293659

RESUMO

INTRODUCTION: Meningiomas are usually considered benign lesions, however a proportion of them shows a more aggressive behavior, defined high-grade meningiomas (HGM). Effective medical treatments are lacking, especially at the time of recurrence. METHODS: Through a retrospective analysis, we examined epidemiological, diagnostic, therapeutic, recurrence information and survival data of HGM treated at our institution between 2010 and 2018. RESULTS: 183 patients (105 females and 78 males), with median age of 58 years (25-88), were included; 168 were atypical, 12 anaplastic, 3 rhabdoid. Overall, m-PFS was 4.2 years, and m-OS was 10.3 years. Gross-total resection had a 5-year survival rate of 95% compared with subtotal/partial resection (86% and 67%) (p = 0.002). Higher expression of Ki-67/MIB-1 seems associated with higher risk of death (HR:1.06 with 95% CI, 1.00-1.12, p = 0.03). No statistically significant differences were seen in survival between the group managed with a wait-and-see strategy vs the group treated with RT while a difference on PFS was seen (4.1 years vs 5.2 years p = 0.03). After second recurrence, the most employed treatments were systemic therapies with a very limited effect on disease control. CONCLUSIONS: Data confirmed the aggressive behavior of HGM. The extent of resection seems to correlate with a favorable outcome regardless histological subtypes. The role of RT remains controversial, with no statistically significant impact on OS but a possible role on PFS. Recurrent HGM remains the real challenge, to date no chemotherapies are able to achieve disease control. Future research should focus on biological/molecular predictors in order to achieve a patient-tailored treatment.


Assuntos
Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/terapia , Meningioma/patologia , Meningioma/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Radioterapia Adjuvante/métodos , Estudos Retrospectivos , Resultado do Tratamento
7.
Neurol Sci ; 31(5): 617-23, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20635108

RESUMO

The biological mechanisms associated with the development and rupture of intracranial aneurysms are not fully understood. To clarify the role of VEGF and the related receptors in the pathophysiology of aneurysm, immunostaining for VEGF, VEGFR1 and VEGFR2 was performed on specimens from six unruptured aneurysms and on two specimens of normal arteries wall as a control. The results were correlated with NO concentration of CSF collected during surgery from 8 patients affected by unruptured aneurysms and in 11 control patients. The immunohistochemical data showed a different pattern of VEGF/VEGFR1/VEGFR2 in aneurysms when compared with control. The results of this preliminary study suggest an imbalance of VEGF, VEGFR1 and VEGFR2, and the interaction of VEGF and NO in the pathophysiology of unruptured aneurysms. Our data support the hypothesis of aneurysm formation associated with a loss of expression of VEGFR1, moderate expression of VEGFR2 and high concentration of nitrate.


Assuntos
Regulação da Expressão Gênica , Aneurisma Intracraniano/líquido cefalorraquidiano , Óxido Nítrico/líquido cefalorraquidiano , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/líquido cefalorraquidiano , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/líquido cefalorraquidiano , Idoso , Feminino , Humanos , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Estudos Retrospectivos , Estatística como Assunto
8.
Phys Med ; 58: 114-120, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30824142

RESUMO

PURPOSE: Radio-guided surgery with ß- decays is a novel technique under investigation. One of the main advantages is its capability to detect small (⩽0.1 ml) samples after injecting the patient with low activity of radiopharmaceutical. This paper presents an experimental method to quantify this feature based on ex-vivo tests on specimens from meningioma patients. METHODS: Patients were enrolled on the basis of the standard uptake value (SUV) and the tumour-to-non-tumour activity ratio (TNR) resulted from 68Ga-DOTATOC PET exams. After injecting the patients with 93-167 MBq of 90Y-DOTATOC, 26 samples excised during surgery were analyzed with a ß- probe. The radioactivity expected on the neoplastic specimens was estimated according to the SUV found in the PET scan and the correlation with the measured counts was studied. The doses to surgeon and medical personnel were also evaluated. RESULTS: Even injecting as low as 1.4 MBq/kg of radiotracer, tumour residuals of 0.1 ml can be detected. A negligible dose to the medical personnel was confirmed. CONCLUSIONS: Radio-guided surgery with ß- decays is a feasible technique with a low radiation dose for both personnel and patient, in particular if the patient is injected with the minimum required activity. A correlation greater than 80% was observed between the measured counts and the expected activity for the lesion samples based on the individual SUV and the TNR. This makes identifiable the minimum injectable radiotracer activity for cases where 90Y is the utilized radionuclide.


Assuntos
Partículas beta , Tomografia por Emissão de Pósitrons , Cirurgia Assistida por Computador/métodos , Radioisótopos de Ítrio/administração & dosagem , Humanos , Injeções , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Exposição Ocupacional/análise , Octreotida/administração & dosagem , Octreotida/análogos & derivados , Doses de Radiação
9.
Oncogene ; 25(10): 1571-83, 2006 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-16247447

RESUMO

Identification of genetic copy number changes in glial tumors is of importance in the context of improved/refined diagnostic, prognostic procedures and therapeutic decision-making. In order to detect recurrent genomic copy number changes that might play a role in glioma pathogenesis and/or progression, we characterized 25 primary glioma cell lines including 15 non glioblastoma (non GBM) (I-III WHO grade) and 10 GBM (IV WHO grade), by array comparative genomic hybridization, using a DNA microarray comprising approx. 3500 BACs covering the entire genome with a 1 Mb resolution and additional 800 BACs covering chromosome 19 at tiling path resolution. Combined evaluation by single clone and whole chromosome analysis plus 'moving average (MA) approach' enabled us to confirm most of the genetic abnormalities previously identified to be associated with glioma progression, including +1q32, +7, -10, -22q, PTEN and p16 loss, and to disclose new small genomic regions, some correlating with grade malignancy. Grade I-III gliomas exclusively showed losses at 3p26 (53%), 4q13-21 (33%) and 7p15-p21 (26%), whereas only GBMs exhibited 4p16.1 losses (40%). Other recurrent imbalances, such as losses at 4p15, 5q22-q23, 6p23-25, 12p13 and gains at 11p11-q13, were shared by different glioma grades. Three intervals with peak of loss could be further refined for chromosome 10 by our MA approach. Data analysis of full-coverage chromosome 19 highlighted two main regions of copy number gain, never described before in gliomas, at 19p13.11 and 19q13.13-13.2. The well-known 19q13.3 loss of heterozygosity area in gliomas was not frequently affected in our cell lines. Genomic hotspot detection facilitated the identification of small intervals resulting in positional candidate genes such as PRDM2 (1p36.21), LRP1B (2q22.3), ADARB2 (10p15.3), BCCIP (10q26.2) and ING1 (13q34) for losses and ECT2 (3q26.3), MDK, DDB2, IG20 (11p11.2) for gains. These data increase our current knowledge about cryptic genetic changes in gliomas and may facilitate the further identification of novel genetic elements, which may provide us with molecular tools for the improved diagnostics and therapeutic decision-making in these tumors.


Assuntos
Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Perfilação da Expressão Gênica , Genômica , Glioblastoma/genética , Glioblastoma/patologia , Glioma/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/metabolismo , Mapeamento Cromossômico , Progressão da Doença , Dosagem de Genes/genética , Triagem de Portadores Genéticos , Marcadores Genéticos , Genômica/métodos , Glioblastoma/metabolismo , Glioma/metabolismo , Glioma/patologia , Homozigoto , Humanos , Hibridização de Ácido Nucleico , Proteômica/métodos
10.
Neurol Res ; 28(5): 538-41, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16808886

RESUMO

Over the last decade, the knowledge on the molecular genetic background of gliomas has dramatically increased. This information provides the basis for the molecular target therapies and molecular tests serve to complement the subjective nature of histopathologic criteria and add useful data regarding response to treatments and prognosis. In particular, the use of loss of heterozygosity (LOH) and methylation specific polymerase chain reaction (PCR) (MSP) based testing of gliomas is already in place and used clinically in several centers. This paper provides a brief overview of these molecular genetic aberrations and discusses the clinical utility, as well as the advantages and disadvantages of such approach. Newly developed molecular techniques, such as LOH testing, fluorescence in situ hybridization (FISH), DNA sequencing and MSP, are currently being employed in assessment of gliomas in some laboratories. However, the clinical use of some markers and the context in which the information obtained should be used are still not entirely understood. Therefore, this paper will focus on validation and implementation of molecular testing in gliomas, with emphasis on LOH on chromosomes 1p, 19q, 17p and 10q and O(6)-methylguanine-DNA methyltransferase (MGMT) methylation status.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Glioma/genética , Neoplasias Encefálicas/metabolismo , Metilação de DNA , Diagnóstico Diferencial , Glioma/metabolismo , Humanos , Perda de Heterozigosidade , Biologia Molecular/tendências , O(6)-Metilguanina-DNA Metiltransferase/genética , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , Prognóstico
11.
Cancer Res ; 59(3): 645-52, 1999 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9973213

RESUMO

Overexpression of interleukin 4 (IL-4) can impair the tumorigenicity of glioma cells, but direct evidence of its antitumor efficacy after in vivo gene transfer into malignant gliomas has not been provided. To test this, we first injected into the brain of Sprague Dawley rats a 1:1 mixture of C6 rat glioblastoma cells and psi2.L4SN20 or E86.L4SN50 retroviral producer cells (RPCs), secreting 20 and 50 ng of IL-4/5 x 10(5) cells/48 h, respectively. Twenty-seven and 56% of rats receiving injections with these low- or medium-level IL-4 RPCs, respectively, survived tumor injection, whereas control rats died in about 1 month. E86.L4SN50 RPCs coinjected with 9L gliosarcoma cells into syngeneic Fischer 344 rats yielded similar results. A novel IL-4 RPC clone expressing higher levels of IL-4, E86.L4SN200, coinjected with 9L cells increased to 75% the fraction of long-term survivors and induced tumor regression in 50% of rats when injected into established 9L gliosarcomas. Cured rats developed an immunological memory because they rejected a challenge of wild-type 9L cells into the contralateral hemisphere. Magnetic resonance imaging was used to monitor 9L and C6 gliomas and gave direct evidence for tumor rejection in treated rats. Immunohistology showed inflammatory infiltrates in IL-4-treated tumors in which CD8+ T lymphocytes were more abundant, although CD4+ T lymphocytes, B lymphocytes, and macrophages were also present. Overall, these findings suggest that IL-4 gene transfer is a new, promising approach for treating malignant gliomas.


Assuntos
Neoplasias Encefálicas/terapia , Terapia Genética/métodos , Glioma/terapia , Interleucina-4/genética , Animais , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Linfócitos T CD8-Positivos/imunologia , DNA Complementar/administração & dosagem , DNA Complementar/genética , DNA Complementar/metabolismo , Feminino , Glioma/imunologia , Glioma/metabolismo , Interleucina-4/biossíntese , Interleucina-4/imunologia , Camundongos , Ratos , Ratos Endogâmicos F344 , Ratos Sprague-Dawley , Retroviridae/genética
12.
Phys Med ; 32(9): 1139-44, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27601248

RESUMO

PURPOSE: A radio-guided surgery technique with ß(-)-emitting radio-tracers was suggested to overcome the effect of the large penetration of γ radiation. The feasibility studies in the case of brain tumors and abdominal neuro-endocrine tumors were based on simulations starting from PET images with several underlying assumptions. This paper reports, as proof-of-principle of this technique, an ex vivo test on a meningioma patient. This test allowed to validate the whole chain, from the evaluation of the SUV of the tumor, to the assumptions on the bio-distribution and the signal detection. METHODS: A patient affected by meningioma was administered 300MBq of (90)Y-DOTATOC. Several samples extracted from the meningioma and the nearby Dura Mater were analyzed with a ß(-) probe designed specifically for this radio-guided surgery technique. The observed signals were compared both with the evaluation from the histology and with the Monte Carlo simulation. RESULTS: we obtained a large signal on the bulk tumor (105cps) and a significant signal on residuals of ∼0.2ml (28cps). We also show that simulations predict correctly the observed yields and this allows us to estimate that the healthy tissues would return negligible signals (≈1cps). This test also demonstrated that the exposure of the medical staff is negligible and that among the biological wastes only urine has a significant activity. CONCLUSIONS: This proof-of-principle test on a patient assessed that the technique is feasible with negligible background to medical personnel and confirmed that the expectations obtained with Monte Carlo simulations starting from diagnostic PET images are correct.


Assuntos
Neoplasias Encefálicas/radioterapia , Meningioma/radioterapia , Tomografia por Emissão de Pósitrons , Radiocirurgia/métodos , Cirurgia Assistida por Computador/métodos , Idoso , Algoritmos , Partículas beta , Neoplasias Encefálicas/diagnóstico por imagem , Simulação por Computador , Estudos de Viabilidade , Feminino , Humanos , Meningioma/diagnóstico por imagem , Modelos Teóricos , Método de Monte Carlo , Exposição Ocupacional/prevenção & controle , Octreotida/análogos & derivados , Octreotida/química , Radiometria , Reprodutibilidade dos Testes
13.
Hum Gene Ther ; 6(6): 763-72, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7548276

RESUMO

Cells expressing the herpes simplex-thymidine kinase (HS-TK) gene as a consequence of retroviral transduction, as well as TK-negative (TK-) bystander cells, can be killed by treatment with ganciclovir (GCV). In vitro, this "bystander effect," has been attributed to metabolic cooperation through gap junctions or to the uptake of apoptotic vesicles. We show that GCV treatment kills TK-negative U-87 glioma cells cocultured with cells that express TK (TK+) but that have lost the capacity for releasing retroviral particles. A photometric enzyme immunoassay identifies histone-associated DNA fragments, typical of apoptosis, in the cytosol of GCV-treated TK+ cells, and apoptotic features are also demonstrated by ultrastructural studies. Northern blot analysis and the reverse transcription polymerase chain reaction (PCR) show that connexin 43, a major constituent of gap junctions, is expressed in TK+ and U-87 cells. The size of U-87 tumors in nude mice subsequently injected with TK+ cells and GCV is not significantly different than in untreated animals; whereas, after injecting 1:1 mixtures of U-87 and TK+ cells, GCV treatment only causes a temporary regression of tumor growth. On the contrary, when the injected mixtures contain PA317.STK.SBA (a retroviral producer cell line that can transduce efficiently the HS-TK gene) and U-87 cells, tumors are destroyed effectively by GCV treatment. Thus, an experimental setting in which U-87 gliomas are matched with cells that are able to express, but not to transduce, the HS-TK gene indicates that the bystander effect kills U-87 cells in vitro by mechanisms associated with apoptotic death. In vivo, this effect is not sufficient to restrain the tumor growth taking place in immunodeficient animals.


Assuntos
Comunicação Celular , Morte Celular/efeitos dos fármacos , Ganciclovir/farmacologia , Animais , Sequência de Bases , Comunicação Celular/genética , Conexina 43/genética , Primers do DNA , Técnicas de Transferência de Genes , Humanos , Camundongos , Camundongos Nus , Microscopia Eletrônica , Dados de Sequência Molecular , Ratos , Ratos Endogâmicos F344 , Simplexvirus/enzimologia , Simplexvirus/genética , Timidina Quinase/genética , Células Tumorais Cultivadas
14.
Hum Gene Ther ; 8(11): 1345-53, 1997 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-9295129

RESUMO

The growth of U-87 or C6 gliomas co-implanted in nude mice with retroviral producer cells (VPC) expressing the herpes simplex virus-thymidine kinase (HSV-tk) gene is only partially impaired by treatment with ganciclovir (GCV). The effect of GCV is even less evident when C6 and VPC are co-implanted into the rat brain. Furthermore, tumors from C6 cells carrying the HSV-tk gene are not eradicated by GCV, although they remain sensitive to GCV when replated in vitro. These limits of the HSV-tk/GCV system in glioma gene therapy may be due to insufficient gene transfer and/or insufficient delivery of GCV to glioma cells. Combination of HSV-tk and one or more cytokines may improve the antitumor efficacy. Among cytokines, interleukin-4 (IL-4) has already been shown to be active against gliomas. In nude mice, GCV treatment inhibited tumor growth more effectively after co-injection of C6 cells with a mixture of VPC transducing IL-4 and HSV-tk genes than after co-injection with either IL-4 or HSV-tk VPC only. In immunocompetent Sprague-Dawley rats, co-injection of IL-4 VPC and C6 cells was also effective in inhibiting the growth of C6 brain tumors, 38% of the animals surviving for at least 2 months. Furthermore, increased and prolonged antitumor efficacy was obtained by transducing both IL-4 and HSV-tk genes.


Assuntos
Antimetabólitos/farmacologia , Ganciclovir/farmacologia , Terapia Genética , Glioma/terapia , Interleucina-4/genética , Simplexvirus/enzimologia , Timidina Quinase/genética , Proteínas Virais/genética , Animais , Feminino , Técnicas de Transferência de Genes , Vetores Genéticos , Interleucina-4/metabolismo , Interleucina-4/uso terapêutico , Camundongos , Camundongos Nus , Ratos , Ratos Sprague-Dawley , Retroviridae/genética , Transdução Genética
15.
J Neuropathol Exp Neurol ; 52(1): 64-70, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8093899

RESUMO

Gerstmann-Sträussler-Scheinker disease in the Indiana kindred is pathologically characterized by deposits of PrP-amyloid, neurofibrillary tangles and degenerating neurites. The aim of this study was to investigate seven patients of different ages for beta PP and A beta immunoreactivities associated with PrP-amyloid deposits and degenerating neurites. In one asymptomatic individual with PrP-amyloid deposits, Alz50 and A beta immunoreactivities were absent. In six symptomatic patients, the degenerating neurites surrounding PrP-amyloid deposits were labeled by Alz50 and by antibodies to synaptophysin, ubiquitin and the N- and C-terminal domains of beta PP. In one symptomatic, senile patient, A beta immunoreactivity was present in the extracellular space, often in association with PrP-amyloid deposits. The analysis of the immunohistochemical findings suggested that in the Indiana kindred the intracellular accumulation of beta PP, synaptophysin and ubiquitinated material most probably revealed a reaction of neurites to PrP-amyloid, whereas the extracellular deposition of A beta was likely an age-related phenomenon.


Assuntos
Precursor de Proteína beta-Amiloide/análise , Doença de Gerstmann-Straussler-Scheinker/metabolismo , Príons/análise , Idoso , Peptídeos beta-Amiloides/análise , Córtex Cerebral/química , Córtex Cerebral/patologia , Demência/genética , Demência/metabolismo , Demência/patologia , Feminino , Doença de Gerstmann-Straussler-Scheinker/genética , Doença de Gerstmann-Straussler-Scheinker/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuritos/química , Proteínas PrPSc
16.
Neurology ; 38(3): 476-80, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3347352

RESUMO

We used a fluorescent dye, quin 2, to measure intracellular free calcium ([Ca++]i) in cultured skeletal muscle cells and skin fibroblasts from five Duchenne muscular dystrophy (DMD) patients and from five controls. We observed an enhanced [Ca++]i level, at rest and after acetylcholine (ACh) stimulation, in DMD muscle cells, but we did not detect any difference between DMD and normal skin fibroblasts. The abnormally higher [Ca++]i transient induced by ACh suggests that it plays a critical role in muscle degeneration. The skin fibroblast results suggests that there is no generalized membrane defect.


Assuntos
Acetilcolina/fisiologia , Cálcio/metabolismo , Citoplasma/metabolismo , Músculos/metabolismo , Distrofias Musculares/metabolismo , Células Cultivadas , Criança , Pré-Escolar , Fibroblastos/metabolismo , Humanos , Músculos/patologia , Distrofias Musculares/patologia , Descanso , Estimulação Química
17.
Cancer Genet Cytogenet ; 74(2): 139-43, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8019958

RESUMO

We have studied alterations of the p53 gene in 27 patients with malignant gliomas. Loss of heterozygosity (LOH) was investigated by microsatellite analysis in 23 patients (22 informative) and detected in nine. Exons 5 through 9 were amplified by polymerase chain reaction (PCR) in these nine patients: alterations were found in five cases (three missense mutations, one non-sense mutation, and one putative deletion), while in four the DNA sequence was normal. In the four patients where LOH could not be studied, the p53 sequence from tumor DNA was normal. These results indicate that microsatellite analysis is a convenient tool for LOH detection at the p53 locus and that mutations of the p53 gene are present in only part of the patients with LOH, implying the possibility that another tumor suppressor gene is located in the proximity of the p53 locus.


Assuntos
Neoplasias Encefálicas/genética , Deleção Cromossômica , Genes p53 , Glioma/genética , Adulto , Idoso , Sequência de Bases , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase
18.
Cancer Genet Cytogenet ; 75(2): 77-89, 1994 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-8055485

RESUMO

We studied the karyotypes of eight differentiated gliomas, 19 anaplastic gliomas, and 23 glioblastomas (GBM). Normal stemlines were present in 70% of the differentiated and anaplastic gliomas; abnormalities were mostly characterized by loss of sex chromosomes. In GBM, on the contrary, only 13% of the stemlines were normal and three groups, 45,XO, near-diploid, and near tetraploid, could be identified. The most frequent alterations among GBM were: total or partial loss of chromosome 10 in nine cases, structural abnormalities of chromosome 9 in seven cases, and loss of the Y chromosome in stemline clones of seven cases. Less frequent abnormalities included chromosomes 7, 1, 3, and 19. Our data support the cytogenetic model of gliomas as multi-stage tumors. GBM, in particular, can originate from the evolution of astrocytomas but can also develop de novo. In both cases loss of genetic material on chromosome 10 seems to play a crucial role.


Assuntos
Neoplasias Encefálicas/genética , Aberrações Cromossômicas , Glioma/genética , Adulto , Idoso , Deleção Cromossômica , Feminino , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade , Cromossomo X , Cromossomo Y
19.
Neurosci Lett ; 114(2): 178-83, 1990 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-2395530

RESUMO

The brains of 7 dogs aged 6 to 18 years have been histochemically and immunohistochemically investigated at the light- and electron microscopy levels for preamyloid deposits and amyloid fibrils to verify the hypothesis that the accumulation of cleavage products of amyloid precursor protein is related not only to Alzheimer's disease but also to the normal aging of the brain. Preamyloid deposits were detected in the neuropil of the cerebral cortex and neostriatum, whereas amyloid fibrils were found in the walls of parenchimal and leptomeningeal vessels. The densities of preamyloid deposits in the neuropil and of deposits of amyloid fibrils in the vessel walls were higher in the brains of the most aged dogs. These findings suggest that aging of the canine brain is characterized by an accumulation of intermediate cleavage products of the amyloid precursor protein in both the neuropil and the vessel walls, and by processing of these products to amyloid fibrils in the vessel walls.


Assuntos
Amiloide/análise , Encéfalo/crescimento & desenvolvimento , Transtornos Cerebrovasculares/veterinária , Doenças do Cão , Precursores de Proteínas/análise , Envelhecimento , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Encéfalo/ultraestrutura , Transtornos Cerebrovasculares/patologia , Cães , Humanos , Microscopia Eletrônica
20.
Neurosci Lett ; 119(1): 56-9, 1990 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-1965862

RESUMO

In Alzheimer's disease, in Down syndrome and in normal aging, scattered deposits of amyloid fibril precursors occur in both cerebral cortex and subcortical grey structures. Within such preamyloid deposits, no degenerating neurites with paired helical filaments have ever been observed. This study, carried out on brains from Alzheimer patients and Down patients, reports on the relationship between preamyloid deposits and neuritic changes. These changes were represented by presynaptic terminal swellings immunolabeled by antisynaptophysin and antiubiquitin antibodies, not by Alz50. These findings support the view that the deposition of amyloid fibril precursors in the neuropil is closely related to presynaptic terminals, although whether the former precedes or follows the development of presynaptic terminal changes is still undetermined.


Assuntos
Doença de Alzheimer/patologia , Amiloide/metabolismo , Encéfalo/patologia , Síndrome de Down/patologia , Sinapses/ultraestrutura , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Antígenos/metabolismo , Encéfalo/metabolismo , Síndrome de Down/metabolismo , Humanos , Imuno-Histoquímica , Proteínas de Membrana/metabolismo , Sinaptofisina , Ubiquitinas/metabolismo
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