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1.
Pituitary ; 22(4): 344-352, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30895501

RESUMO

PURPOSES: To test if the antibody array strategy could be utilized to simultaneously detect the secretion of multiple growth factors by human pituitary GH-adenomas and to measure octreotide-induced alterations. METHODS: Specimens of human pituitary adenomas were cultured and incubated with or without octreotide for 24 h. Conditional media were analyzed by human growth factor antibody array and VEGF concentrations were measured by ELISA. Media were also analyzed for GH concentrations. p21 expression levels were examined by Western blot of the specimens lysates. RESULTS: The antibody arrays successfully identified growth factors secreted by GH-adenomas in vitro. Octreotide treatment induced both elevations and reductions in growth factors secretion. GH response to octreotide was measured, and in this small-sized study resistant and sensitive GH-adenomas presented with no unique secretome pattern of each of the groups. Octreotide-induced VEGF alterations analyzed by the antibody array and by ELISA were not fully matched. CONCLUSIONS: This study suggests that the broad proteomic strategy of antibody arrays may be utilized to study the growth factors secretion pattern of GH-adenomas and its regulation by somatostatin analogs or other compounds.


Assuntos
Adenoma/metabolismo , Anticorpos/metabolismo , Hormônio do Crescimento Humano/metabolismo , Ensaio de Imunoadsorção Enzimática , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Humanos , Octreotida/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
2.
Brain ; 140(3): 568-581, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28364549

RESUMO

Cellular distribution and dynamics of mitochondria are regulated by several motor proteins and a microtubule network. In neurons, mitochondrial trafficking is crucial because of high energy needs and calcium ion buffering along axons to synapses during neurotransmission. The trafficking kinesin proteins (TRAKs) are well characterized for their role in lysosomal and mitochondrial trafficking in cells, especially neurons. Using whole exome sequencing, we identified homozygous truncating variants in TRAK1 (NM_001042646:c.287-2A > C), in six lethal encephalopathic patients from three unrelated families. The pathogenic variant results in aberrant splicing and significantly reduced gene expression at the RNA and protein levels. In comparison with normal cells, TRAK1-deficient fibroblasts showed irregular mitochondrial distribution, altered mitochondrial motility, reduced mitochondrial membrane potential, and diminished mitochondrial respiration. This study confirms the role of TRAK1 in mitochondrial dynamics and constitutes the first report of this gene in association with a severe neurodevelopmental disorder.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Encefalopatias/genética , Encefalopatias/patologia , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/genética , Encefalopatias/diagnóstico por imagem , Encefalopatias/mortalidade , Células Cultivadas , Pré-Escolar , Consanguinidade , Saúde da Família , Feminino , Fibroblastos/patologia , Fibroblastos/ultraestrutura , Estudos de Associação Genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Consumo de Oxigênio/genética , Transporte Proteico/genética , Transfecção
3.
Ann Neurol ; 75(6): 967-70, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24817010

RESUMO

Chronic measles virus infection of the brain causes subacute sclerosing panencephalitis (SSPE), a progressive, relentless fatal disorder. We report a 52-year-old male who developed focal, chronic persistent measles virus infection of the brain following interferon and ribavirin therapy for hepatitis C, and who responded to steroid therapy. This case, diametrically different from SSPE, has 2 unique features, its focal nature and its permissive response to steroids, that may add to the understanding of the pathogenesis of SSPE and the mechanism enabling viruses to evade the immune response and establish persistent brain infection.


Assuntos
Encefalite Viral/tratamento farmacológico , Vírus do Sarampo/patogenicidade , Esteroides/uso terapêutico , Antígenos CD/metabolismo , Encefalite Viral/patologia , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
4.
AIDS Res Ther ; 11(1): 4, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24447375

RESUMO

OBJECTIVE: Central nervous system involvement in AIDS patients can present at any stage of the disease. Brain lesions detected in imaging studies are usually treated empirically. A brain biopsy is indicated in the absence of clinical and radiologic improvement. In the present study, 16 AIDS patients underwent brain biopsy. We evaluated the diagnostic yield of the brain biopsy and the changes in the disease course. MATERIALS AND METHODS: Sixteen consecutive AIDS patients (12 men, 4 women; mean age 40.8 years) underwent a brain biopsy at Sheba Medical Center between 1997 and 2009. A retrospective analysis was performed and the clinical outcome was recorded. RESULTS: Median CD4 count before biopsy was 62.6. Magnetic resonance images revealed multiple lesions in 12 patients and enhancing lesions in 12 patients. A total of 19 biopsies were performed in 16 patients. In the present series, the initial procedures provided a diagnostic yield of 81.25% (13 diagnostic cases from 16 procedures in 16 patients). Two of these patients underwent repeated biopsies that were eventually diagnostic . If repeated biopsies were taken into consideration, the diagnostic yield was 93.75% (15 diagnostic cases in 16 patients). The rate of hemorrhagic complications was 10.5% (2 hemorrhages in 19 procedures).Pathologic examination revealed parasitic and fungal infections in 6 patients (6/16; 38%), progressive multifocal leukoencephalopathy in 4 patients (4/16; 25%), AIDS encephalopathy in 4 patients (4/16; 25%), and lymphoma in 1 patient (1/16; 6%). One patient had a nonspecific inflammatory process (6%). The treatment modality was modified in 12 patients and led to clinical and radiologic improvement in 8 patients. CONCLUSIONS: Brain biopsy should be considered when empiric treatment of central nervous system lesions in AIDS patients fails. Biopsy is diagnostic in the majority of patients. The diagnosis allows for treatment modifications, which lead to clinical and radiologic improvement in some patients.

5.
Anticancer Drugs ; 24(3): 315-23, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23348245

RESUMO

Glioblastoma multiforme (GBM) is the most malignant and frequent brain tumor, with an aggressive growth pattern and poor prognosis despite best treatment modalities. Long-term survival of patients with GBM is rare. Optic glioma represents 0.6-1.2% of all brain tumors. Unlike low-grade optic gliomas in children, optic gliomas in adults are highly aggressive and death usually occurs in less than a year. Prolonged progression-free survival and survival rates have been reported in association with induced hypothyroidism in two clinical trials for recurrent GBM. We present the clinical, radiological, and pathological findings in a patient with inoperable GBM of the optic chiasm. Following failure of initial, standard radiation and temozolomide therapy, chemical hypothyroidism was induced using the antithyroid thioamide, propylthiouracil, followed by carboplatin chemotherapy. Initial thyroid stimulating hormone, free T4, and free T3 analysis was carried out and then monthly. This patient responded rapidly to treatment (clinically and with tumor regression within 4 weeks) on two separate occasions with an extended remission period (2.5 years) and prolonged overall survival (4.5 years). We report the successful long-term tumor response to medically induced chemical hypothyroidism in conjunction with carboplatinum chemotherapy of an adult patient with grade IV GBM of the optic chiasm. These clinical observations find mechanistic support from the recent identification of potent mitogenic actions of the thyroid hormone, L-thyroxine, in malignant glioma through binding to a cognate thyroid hormone receptor on the αvß3 integrin. Approaches to block its activity are now explored in preclinical studies.


Assuntos
Carboplatina/uso terapêutico , Hipotireoidismo/induzido quimicamente , Glioma do Nervo Óptico/tratamento farmacológico , Glioma do Nervo Óptico/patologia , Antitireóideos/uso terapêutico , Terapia Combinada , Humanos , Hipotireoidismo/sangue , Masculino , Pessoa de Meia-Idade , Quiasma Óptico/patologia , Glioma do Nervo Óptico/mortalidade , Glioma do Nervo Óptico/radioterapia , Propiltiouracila/uso terapêutico , Tiroxina/sangue , Resultado do Tratamento , Tri-Iodotironina/sangue
6.
Mod Pathol ; 23(6): 814-23, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20348879

RESUMO

Identification of the tissue of origin of a tumor is vital to its management. Previous studies showed tissue-specific expression patterns of microRNA and suggested that microRNA profiling would be useful in addressing this diagnostic challenge. MicroRNAs are well preserved in formalin-fixed, paraffin-embedded (FFPE) samples, further supporting this approach. To develop a standardized assay for identification of the tissue origin of FFPE tumor samples, we used microarray data from 504 tumor samples to select a shortlist of 104 microRNA biomarker candidates. These 104 microRNAs were profiled by proprietary quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) on 356 FFPE tumor samples. A total of 48 microRNAs were chosen from this list of candidates and used to train a classifier. We developed a clinical test for the identification of the tumor tissue of origin based on a standardized protocol and defined the classification criteria. The test measures expression levels of 48 microRNAs by qRT-PCR, and predicts the tissue of origin among 25 possible classes, corresponding to 17 distinct tissues and organs. The biologically motivated classifier combines the predictions generated by a binary decision tree and K-nearest neighbors (KNN). The classifier was validated on an independent, blinded set of 204 FFPE tumor samples, including nearly 100 metastatic tumor samples. The test predictions correctly identified the reference diagnosis in 85% of the cases. In 66% of the cases the two algorithm predictions (tree and KNN) agreed on a single-tissue origin, which was identical to the reference diagnosis in 90% of cases. Thus, a qRT-PCR test based on the expression profile of 48 tissue-specific microRNAs allows accurate identification of the tumor tissue of origin.


Assuntos
Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Testes Genéticos/métodos , MicroRNAs/análise , Neoplasias Primárias Desconhecidas/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Algoritmos , Árvores de Decisões , Alemanha , Humanos , Israel , Neoplasias Primárias Desconhecidas/genética , Análise de Sequência com Séries de Oligonucleotídeos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos
7.
Neurol India ; 67(6): 1431-1436, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31857529

RESUMO

AIMS AND OBJECTIVES: To review a series of patients with brain metastases from ovarian cancer at a single institution. To describe treatment modalities, their outcomes and to determine prognostic factors. PATIENTS AND METHODS: Between January 1995 and December 2014, 25 patients with ovarian cancer brain metastases were treated at The Sheba Medical Center. The medical records were retrospectively reviewed to collect demographic, clinical, and imaging data as well as the information on the treatment modalities used and their outcomes. RESULTS: Mean patient age at the time of brain metastasis diagnosis was 62.7 years. The median interval between the diagnosis of primary cancer and brain metastasis was 42.3 months. Neurologic deficits, headache, and seizure were the most common symptoms. The brain was the only site of metastasis in 20% of the patients. Active ovarian cancer at the time of diagnosis of brain metastasis was observed in half of the patients with systemic disease. Multiple brain metastases were observed in 25% of the patients. We treated 11 patients with surgery plus radiation therapy protocols in various orders: surgery followed by complementary whole-brain radiation therapy (WBRT), surgery followed by stereotactic radiosurgery (SRS), and surgery followed by WBRT and then by adjuvant SRS. Five patients underwent surgery alone and nine patients were treated with radiation alone (WBRT, SRS, or both). Univariate analysis for predictors of survival demonstrated that age above 62.7 years at the time of central nervous system involvement was a significant risk factor and leptomeningeal disease was a poor prognostic factor in reference to supra-tentorial lesions. Multivariate analysis for predictors of survival, however, showed that multiple brain lesions (>4) were a poor prognostic factor, and multivariate analysis of the time to progression revealed that combined treatments of surgery and radiation resulted in longer median periods of progression-free survival than each modality alone. CONCLUSION: We conclude that the only significant predictors of survival or progression-free survival in our cohort were the number of brain metastases and the treatment modality.


Assuntos
Neoplasias Encefálicas/secundário , Irradiação Craniana , Cistadenocarcinoma Seroso/secundário , Procedimentos Neurocirúrgicos , Neoplasias Ovarianas/patologia , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Terapia Combinada , Cistadenocarcinoma Seroso/mortalidade , Cistadenocarcinoma Seroso/terapia , Bases de Dados Factuais , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/terapia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
8.
World Neurosurg ; 130: e324-e332, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31228703

RESUMO

BACKGROUND: Klotho, a single-pass transmembrane protein associated with premature aging, acts as a tumor suppressor gene by inhibiting insulin/insulin-like growth factor-1 and fibroblast growth factor pathways. Downregulated Klotho expression is reported in melanoma, mesothelioma, bladder, breast, gastric, cervix, lung, and kidney cancers and is associated with a poor prognosis. Klotho expression and Klotho promoter hypermethylation are predictive factors for patient prognosis. METHODS: To investigate the potential role of Klotho in glioblastoma-multiforme (GBM), 22 GBM samples were collected from the Sheba Tumor Bank and examined. RESULTS: We found that increased Klotho messenger ribonucleic acid (RNA) expression predicted longer survival (P = 0.03) of GBM patients. Methylation analysis was performed on bisulfite-treated deoxyribonucleic acid from the GBM patient samples using ionization time-of-flight mass spectrometry according to the Sequenom EpiTYPER protocols. Klotho promoter hypermethylation was detected in 65% of the GBM samples and correlated significantly with improved survival (P < 0.04). We found 3 major Klotho promotor hypermethylation sites located 585-579 bp, 540-533 bp, and 537-534 bp upstream of the transcription start site. Methylated deoxyribonucleic acid immunoprecipitation studies confirmed these results. Notably, the messenger RNA expression in these GBM samples revealed an unexpected linear correlation with methylation of these 3 hypermethylation sites identified in the Klotho promotor. Thus Klotho expression and methylation could predict prognosis in patients with GBM. CONCLUSIONS: Epigenetic regulation in GBM appears to be complicated. Specific CpG islands affect genes or micro RNAs that interact to control Klotho expression. The diverse effects of these islands may be due to unique factors of GBM.


Assuntos
Neoplasias Encefálicas/genética , Carcinogênese/genética , Progressão da Doença , Glioblastoma/genética , Glucuronidase/genética , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Carcinogênese/metabolismo , Carcinogênese/patologia , Regulação Neoplásica da Expressão Gênica , Glioblastoma/diagnóstico , Glioblastoma/metabolismo , Glioma/diagnóstico , Glioma/genética , Glioma/metabolismo , Glucuronidase/biossíntese , Humanos , Proteínas Klotho , Células MCF-7 , Gradação de Tumores/métodos , Prognóstico
9.
Clin Transl Radiat Oncol ; 15: 1-6, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30547098

RESUMO

•Of 310 brain tumors patients recruited, histology of 99 lesions was available.•Of those, 5 were histologically confirmed as radiation-induced malformations.•TRAMs cannot differentiate active tumor from vascular malformation.

10.
Neuroepidemiology ; 31(4): 264-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18931523

RESUMO

BACKGROUND: Glial brain tumors span a wide range of neoplasms with distinct clinical and histopathological features. This report presents the descriptive epidemiology of glial tumors by histological subtype and tumor behavior. METHODS: The study population included all incident cases of glial tumors diagnosed in Israel during March 2001 to July 2003. Age-standardized incidence rates (ASR) were calculated using the world population as a standard. RESULTS: A total of 548 tumors were diagnosed, of which 520 had histological confirmation. The ASR of all adult (>20 years) glial tumors was 5.82/100,000 (7.11 for males; 4.75 for females, p < 0.001). The majority of tumors (78%) were classified as high grade; astrocytic tumors were the most frequent (85%), with glioblastoma multiforme accounting for 70% of them. A significant positive association was shown between age at diagnosis and grade. The highest ASR was seen for Europe- and-American-born, followed by Israeli, Asian and African-born individuals (6.78, 5.86, 4.94 and 3.84/100,000, respectively). CONCLUSIONS: In general, these results describing data of incident cases of pathologically validated glial tumors are consistent with previous reports. To enhance our understanding of these diseases, epidemiological studies should rely on well-defined histological tumor types, incorporating comprehensive information which will allow comparability between different groups of patients.


Assuntos
Neoplasias Encefálicas/epidemiologia , Glioma/epidemiologia , Judeus/estatística & dados numéricos , Adulto , África/epidemiologia , Idoso , Idoso de 80 Anos ou mais , América/epidemiologia , Ásia/epidemiologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Etnicidade/estatística & dados numéricos , Europa (Continente)/epidemiologia , Feminino , Glioma/patologia , Glioma/cirurgia , Saúde Global , Humanos , Incidência , Israel/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prevalência , Caracteres Sexuais
11.
Heart Lung Circ ; 17(5): 428-32, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17723320

RESUMO

We describe a case of cardiac papillary fibroelastoma in a 33-year-old man. The diagnosis was established by echocardiography. Computerised tomographic angiography gave no evidence of coronary stenosis, but illustrated a radiopaque filling defect in the left ventricle. The papillary fibroelastoma was removed together with the involved chorda, and an artificial chord was implanted under cardiopulmonary bypass. Histological study confirmed the diagnosis of papillary fibroelastoma. Due to the potentials of cerebral and coronary embolisation, surgical management to the patients with a papillary fibroelastoma is highly recommended.


Assuntos
Ponte Cardiopulmonar , Fibroma/patologia , Fibroma/cirurgia , Neoplasias Cardíacas/patologia , Neoplasias Cardíacas/cirurgia , Adulto , Ecocardiografia , Ventrículos do Coração/patologia , Ventrículos do Coração/cirurgia , Humanos , Masculino , Tomografia Computadorizada por Raios X
12.
Sci Rep ; 6: 21277, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26888362

RESUMO

AIMS: Chordomas and chondrosarcomas are malignant mesenchymal tumours with overlapping morphological and immunohistochemical (IHC) characteristics. Our aim was to evaluate the IHC expression of α-methylacyl-CoA racemase (AMACR/P504S), ß-catenin and E-cadherin in chordomas relative to chondrosarcomas and assess the utility of these markers for differential diagnosis. METHODS: Archival sections of 18 chordomas, 19 chondrosarcomas and 10 mature cartilage samples were immunostained and scored for AMACR, ß-catenin and E-cadherin and the relative differential capacity of each marker was calculated. In addition, AMACR mRNA level was assessed in 5 chordomas by RT-PCR and evaluated by comparative CT method. RESULTS: AMACR and ß-catenin stained 88.9% and 94.1% of the chordomas respectively, 21.1% and 10.5% of the chondrosarcomas correspondingly and none of the mature cartilage samples. E-cadherin stained positively 82.4% of the chordomas, 36.8% of the chondrosarcomas and 42.9% of the mature cartilage cases. Both AMACR and ß-catenin showed statistically significant difference between chordomas and chondrosarcomas (p < 0.001 for both), unlike E-cadherin. AMACR was detected at the mRNA level. CONCLUSIONS: AMACR is expressed in most of the chordomas but only in a minority of chondrosarcomas. AMACR may serve as IHC marker of chordoma with differentiating ability comparable to that of ß-catenin.


Assuntos
Biomarcadores Tumorais/biossíntese , Condroma/enzimologia , Condrossarcoma/enzimologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Racemases e Epimerases/biossíntese , Cartilagem/enzimologia , Cartilagem/patologia , Condroma/patologia , Condrossarcoma/patologia , Feminino , Humanos , Masculino
13.
J Clin Neurosci ; 22(2): 326-30, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25443081

RESUMO

Malignant gliomas are the most common primary brain tumors in adults. The disease has no known etiology, progresses rapidly, and is fatal despite current therapies. Human cytomegalovirus (HCMV) is a beta herpes virus that is trophic for glial cells and infects 50% to 90% of the adult human population. HCMV-mediated disease in immunosuppressed patients has highlighted the possible role of this virus in the development of other diseases, particularly inflammatory diseases such as vascular diseases, autoimmune diseases, and certain malignancies. Sensitive detection of viral DNA, mRNA, and antigens in tumor tissues, as well as seroepidemiologic evidence, suggest a link between HCMV and several human malignancies. HCMV gene products are proposed to dysregulate multiple cellular pathways involved in oncogenesis, such as cell cycle regulation, apoptosis, migration, and angiogenesis. These theories, currently being researched, suggest that HCMV acts as an oncomodulator in malignancies. We investigated the association between HCMV infection and reactivation, and malignant gliomas. An open, matched case-control, parallel group pilot study was performed in a tertiary referral center. The HCMV viral load in peripheral blood and tumor samples of 19 patients newly diagnosed with glioblastoma multiforme was compared with a matched control cohort comprising 19 patients newly diagnosed with non-malignant brain tumors. There was no significant correlation between peripheral blood and tumor tissue HCMV viral load in patients with glioblastoma multiforme compared to the control cohort. The findings of the present study did not support an oncomodulatory role for HCMV in malignant gliomas.


Assuntos
Neoplasias Encefálicas/virologia , Infecções por Citomegalovirus/epidemiologia , Glioma/virologia , Adulto , Idoso , Estudos de Casos e Controles , Citomegalovirus , DNA Viral/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Carga Viral
14.
Eur J Paediatr Neurol ; 19(6): 688-93, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26233519

RESUMO

Identification of CD59 p.Cys89Tyr mutation in 5 patients from North-African Jewish origin presenting with chronic inflammatory demyelinating polyradiculoneuropathy like disease and chronic hemolysis, led us to reinvestigate an unsolved disease in 2 siblings from the same origin who died 17 years ago. The two patients carried the same CD59 gene mutation previously described by our group. These children had quiet similar disease course but in addition developed devastating recurrent brain infarctions, retinal and optic nerve involvement. Revising the brain autopsy of one of these patients confirmed the finding of multiple brain infarctions of different ages. CD59 protein expression was missing on brain endothelial cells by immunohistochemical staining. This new data expands the clinical spectrum of CD59 mutations and further emphasizes the need for its early detection and treatment.


Assuntos
Anemia Hemolítica/complicações , Infarto Cerebral/genética , Hemoglobinúria/complicações , Doenças Retinianas/genética , Adolescente , Antígenos CD59/genética , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Mutação , Linhagem , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/genética
15.
Neuro Oncol ; 17(3): 457-65, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25452395

RESUMO

BACKGROUND: Conventional magnetic resonance imaging (MRI) is unable to differentiate tumor/nontumor enhancing tissues. We have applied delayed-contrast MRI for calculating high resolution treatment response assessment maps (TRAMs) clearly differentiating tumor/nontumor tissues in brain tumor patients. METHODS: One hundred and fifty patients with primary/metastatic tumors were recruited and scanned by delayed-contrast MRI and perfusion MRI. Of those, 47 patients underwent resection during their participation in the study. Region of interest/threshold analysis was performed on the TRAMs and on relative cerebral blood volume maps, and correlation with histology was studied. Relative cerebral blood volume was also assessed by the study neuroradiologist. RESULTS: Histological validation confirmed that regions of contrast agent clearance in the TRAMs >1 h post contrast injection represent active tumor, while regions of contrast accumulation represent nontumor tissues with 100% sensitivity and 92% positive predictive value to active tumor. Significant correlation was found between tumor burden in the TRAMs and histology in a subgroup of lesions resected en bloc (r(2) = 0.90, P < .0001). Relative cerebral blood volume yielded sensitivity/positive predictive values of 51%/96% and there was no correlation with tumor burden. The feasibility of applying the TRAMs for differentiating progression from treatment effects, depicting tumor within hemorrhages, and detecting residual tumor postsurgery is demonstrated. CONCLUSIONS: The TRAMs present a novel model-independent approach providing efficient separation between tumor/nontumor tissues by adding a short MRI scan >1 h post contrast injection. The methodology uses robust acquisition sequences, providing high resolution and easy to interpret maps with minimal sensitivity to susceptibility artifacts. The presented results provide histological validation of the TRAMs and demonstrate their potential contribution to the management of brain tumor patients.


Assuntos
Neoplasias Encefálicas/patologia , Encéfalo/patologia , Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/patologia , Fatores de Tempo , Adulto Jovem
16.
J Clin Endocrinol Metab ; 88(8): 3724-30, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12915661

RESUMO

Pituitary GH secretion is regulated by hypothalamic hormones and peripheral factors. Cell-cell contact may also have an important role in regulating pituitary hormone expression and secretion. The role of pituicyte cell-cell contact mediated by N-cadherin and neural cell adhesion molecule (N-CAM) was studied in the regulation of GH secretion. RT-PCR showed N-cadherin mRNA expression in eight of 12 of GH-secreting adenomas compared with one of seven of prolactin-cell adenomas. N-cadherin and N-CAM were similarly expressed in adenomas and in adult and fetal normal pituitary tissues. The effects of CAM homophilic binding on GH secretion from dispersed human fetal pituitary cultures were studied by manipulating CAM mediated cell-cell contact using either soluble N-cadherin-Fc or pituitary cells cocultured with NIH-3T3 cells stably expressing CAMs. CAM stimulation increased GH secretion from pituitary fetal cultures by 40-60% (P < 0.05) and also from cultured GH adenoma cells by 40-75% (P < 0.05). Disrupting N-cadherin homophilic binding by anti-N-cadherin antibody decreased fetal, but not tumorous GH secretion by 40% (P < 0.05). This study indicates that pituitary cell-cell contact mediated by homophilic interactions between adhesion molecules regulates human GH secretion.


Assuntos
Caderinas/fisiologia , Hormônio do Crescimento Humano/metabolismo , Moléculas de Adesão de Célula Nervosa/fisiologia , Hipófise/fisiologia , Células 3T3 , Adenoma/metabolismo , Adulto , Animais , Células Cultivadas , Técnicas de Cocultura , Feminino , Feto/metabolismo , Imunofluorescência , Humanos , Masculino , Camundongos , Microscopia Eletrônica , Hipófise/química , Neoplasias Hipofisárias/metabolismo , Gravidez , RNA Mensageiro/biossíntese , RNA Mensageiro/isolamento & purificação , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Neurosurgery ; 55(3): 562-7; discussion 567-8, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15335423

RESUMO

OBJECTIVE: Gliomas account for most primary brain tumors in adults, and survival correlates with the grade and vascularity of the tumor. The degree of tumor-related angiogenesis seems to be a significant predictor of tumor progression, recurrence, and metastatic spread in a variety of malignant diseases, including brain tumors. Our study's objective was to quantify the levels of two angiogenic factors, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF), in the cerebrospinal fluid (CSF) and serum of patients with gliomas and to correlate these levels with tumor grade, vascularity, and overall survival. METHODS: Twenty-six patients with the diagnosis of cerebral glioma (19 high-grade, 7 low-grade) comprised the study group. Ten patients with communicating hydrocephalus served as controls. Levels of VEGF and bFGF in the CSF and serum were determined using enzyme-linked immunosorbent assay analysis. Tumor vascularity was graded qualitatively using immunohistochemical staining for CD34. Nonparametric statistical techniques were used for data analysis. RESULTS: Median levels of bFGF and VEGF in the CSF were significantly higher in patients with high-grade glioma as compared with patients with low-grade glioma or hydrocephalus (bFGF levels, 52, 26, and 24 ng/ml, respectively, P < 0.0001; VEGF levels, 17.6, 7.2, and 8.3 ng/ml, respectively, P < 0.005). A significant correlation was found comparing CSF levels of bFGF with levels of VEGF (P < 0.001). The levels of the angiogenic factors in the CSF correlated with the degree of tumor vascularity and were adversely associated with patient survival. Serum levels of the angiogenic factors showed no correlation to tumor grade, vascularity, or survival. CONCLUSION: Our data suggest that CSF levels of bFGF and VEGF may serve as an additional marker for tumor grading and vascularity and may help predict survival.


Assuntos
Indutores da Angiogênese/líquido cefalorraquidiano , Astrocitoma/irrigação sanguínea , Neoplasias Encefálicas/irrigação sanguínea , Fator 2 de Crescimento de Fibroblastos/líquido cefalorraquidiano , Glioblastoma/irrigação sanguínea , Neovascularização Patológica/líquido cefalorraquidiano , Fator A de Crescimento do Endotélio Vascular/líquido cefalorraquidiano , Astrocitoma/líquido cefalorraquidiano , Astrocitoma/mortalidade , Neoplasias Encefálicas/líquido cefalorraquidiano , Neoplasias Encefálicas/mortalidade , Feminino , Glioblastoma/líquido cefalorraquidiano , Glioblastoma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/mortalidade , Valor Preditivo dos Testes , Prognóstico , Estatística como Assunto , Análise de Sobrevida
18.
J Neurosurg ; 97(5): 1078-82, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12450029

RESUMO

OBJECT: Ionizing radiation is the only established risk factor recognized today in the causation of meningioma. The aim of the present report is to describe the demographic and clinical characteristics of a large series of 253 patients with radiation-induced meningiomas (RIMs). These parameters were compared with those of 41 patients with meningiomas in whom there was no previous history of irradiation (non-RIM group) and with other series of patients presented in the literature. METHODS: The cases of RIM were recruited from a cohort of approximately 11,000 individuals who had been treated with ionizing radiation during childhood for tinea capitis and from a group of individuals who, as adults, applied for compensation because of that treatment. The non-RIM group was identified through the Israeli Cancer Registry. Exposure to radiation was carefully validated among all cases of RIM and absence of previous irradiation was verified for all patients in the non-RIM group. Significantly, a lower patient age at diagnosis, higher prevalence of calvarial tumors, higher proportion of multiple meningiomas, and a nonsignificant higher recurrence rate were observed among patients with RIM compared with the non-RIM group. The mean latency period from date of radiation exposure to development of a meningioma among the RIM group was approximately 36 years. CONCLUSIONS: The findings of this study agree with those of other studies indicating the demographic, clinical, and even genetic variability between RIM and non-RIM cases. The existence of two different subtypes of meningiomas may have profound implications for screening, early diagnosis, and therapy of meningiomas.


Assuntos
Neoplasias Meníngeas/etiologia , Meningioma/etiologia , Neoplasias Induzidas por Radiação , Adulto , Distribuição por Idade , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/epidemiologia , Fatores de Tempo , Tinha do Couro Cabeludo/radioterapia
19.
J Neurosurg ; 100(3): 472-9, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15035283

RESUMO

OBJECT: A minority of patients with recurrent glioblastomas multiforme (GBMs) responds to systemic chemotherapy. The authors investigated the safety and efficacy of intratumoral convection-enhanced delivery (CED) of paclitaxel in patients harboring histologically confirmed recurrent GBMs and anaplastic astrocytomas. METHODS: Fifteen patients received a total of 20 cycles of intratumoral CED of paclitaxel. The patients were observed daily by performing diffusion-weighted (DW) magnetic resonance (MR) imaging to assess the convective process and routine diagnostic MR imaging to identify the tumor response. Effective convection was determined by the progression of the hyperintense signal within the tumor on DW MR images, which corresponded to a subsequent lytic tumor response displayed on conventional MR images. Of the 15 patients, five complete responses and six partial responses were observed, giving a response rate of 73%. The antitumor effect was confirmed by one biopsy and three en bloc resections of tumors, which showed a complete response, and by one tumor resection, which demonstrated a partial response. Lack of convection and a poor tumor response was associated with leakage of the convected drug into the subarachnoid space, ventricles, and cavities formed by previous resections, and was seen in tumors containing widespread necrosis. Complications included transient chemical meningitis in six patients, infectious complications in three patients, and transient neurological deterioration in four patients (presumably due to increased peritumoral edema). CONCLUSIONS: On the basis of our data we suggest that CED of paclitaxel in patients with recurrent malignant gliomas is associated with a high antitumor response rate, although it is associated with a significant incidence of treatment-associated complications. Diffusion-weighted MR images may be used to predict a response by demonstrating the extent of convection during treatment. Optimization of this therapeutic approach to enhance its efficacy and reduce its toxicity should be explored further.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Convecção , Glioma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Paclitaxel/administração & dosagem , Adulto , Idoso , Antineoplásicos Fitogênicos/uso terapêutico , Terapia Combinada , Imagem de Difusão por Ressonância Magnética , Relação Dose-Resposta a Droga , Feminino , Lobo Frontal/patologia , Lobo Frontal/cirurgia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/cirurgia , Glioma/patologia , Glioma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Paclitaxel/uso terapêutico , Lobo Parietal/patologia , Lobo Parietal/cirurgia , Estudos Prospectivos , Lobo Temporal/patologia , Lobo Temporal/cirurgia
20.
Pediatr Neurol ; 27(5): 392-6, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12504209

RESUMO

We report an uncommon association of intractable epilepsia partialis continua that was the main presentation of widespread gliomatosis cerebri in two females. Both children had a preceding prolonged secondary generalized seizure 2-4 months before the evolution of epilepsia partialis continua, including recurrent clusters of left-sided myoclonic twitching and sensory impairment. During these events, the children remained fully alert. These seizures were corroborated by prolonged focal epileptic spike/wave discharges evident on the electroencephalograms. Cerebral magnetic resonance imaging in the first patient demonstrated a wide area of increasing signals over the right frontocentral regions, along with diffuse cortical-subcortical infiltration impinging on the left hemisphere. In the second patient a cortical lesion was suspected. Evaluation for Rasmussen's encephalitis, focal cortical dysplasia, or a gliomatous process was conducted; the patients underwent a stereotactic brain biopsy in which the histologic findings were compatible with gliomatosis cerebri with diffuse widespread infiltration of glioma cells with no constitution of a circumscribed tumor mass. The first patient was treated with cranial radiation, chemotherapy, steroids, and combined antiepileptic therapy. The focal seizures gradually but markedly decreased in frequency, and sensory impairment abated within 18 months after establishment of the diagnosis and ensuing therapy. Cognition remains intact. The second female died 2 years after presentation despite massive chemotherapy and antiepileptic medications. Although rare, gliomatosis cerebri should be taken into account in the differential diagnosis of epilepsia partialis continua in children to facilitate a rapid diagnosis and initiation of prompt treatment of this rare disorder that may respond to a concurrent effective combination of cranial radiation, chemotherapy, and antiepileptic medications.


Assuntos
Epilepsia Parcial Contínua/diagnóstico , Neoplasias Neuroepiteliomatosas/diagnóstico , Encéfalo/patologia , Criança , Pré-Escolar , Terapia Combinada , Diagnóstico Diferencial , Eletroencefalografia , Encefalite/diagnóstico , Epilepsia Parcial Contínua/etiologia , Evolução Fatal , Feminino , Humanos , Imageamento por Ressonância Magnética , Mioclonia/etiologia , Neoplasias Neuroepiteliomatosas/complicações , Neoplasias Neuroepiteliomatosas/patologia , Neoplasias Neuroepiteliomatosas/terapia
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