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1.
Mol Psychiatry ; 22(8): 1119-1125, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27956742

RESUMO

To assess the role of rare copy number variations in Alzheimer's disease (AD), we conducted a case-control study using whole-exome sequencing data from 522 early-onset cases and 584 controls. The most recurrent rearrangement was a 17q21.31 microduplication, overlapping the CRHR1, MAPT, STH and KANSL1 genes that was found in four cases, including one de novo rearrangement, and was absent in controls. The increased MAPT gene dosage led to a 1.6-1.9-fold expression of the MAPT messenger RNA. Clinical signs, neuroimaging and cerebrospinal fluid biomarker profiles were consistent with an AD diagnosis in MAPT duplication carriers. However, amyloid positon emission tomography (PET) imaging, performed in three patients, was negative. Analysis of an additional case with neuropathological examination confirmed that the MAPT duplication causes a complex tauopathy, including prominent neurofibrillary tangle pathology in the medial temporal lobe without amyloid-ß deposits. 17q21.31 duplication is the genetic basis of a novel entity marked by prominent tauopathy, leading to early-onset dementia with an AD clinical phenotype. This entity could account for a proportion of probable AD cases with negative amyloid PET imaging recently identified in large clinical series.


Assuntos
Doença de Alzheimer/genética , Cromossomos Humanos Par 17/genética , Demência/genética , Idoso , Encéfalo/metabolismo , Estudos de Casos e Controles , Variações do Número de Cópias de DNA/genética , Feminino , Dosagem de Genes , Duplicação Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/patologia , Neuroimagem , Tauopatias/genética , Proteínas tau/genética , Proteínas tau/metabolismo
2.
Clin Genet ; 90(4): 366-71, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26748608

RESUMO

Danon disease (DD) is a rare X-linked multisystem disorder caused by mutations of the LAMP2 gene and characterized by intellectual disability, skeletal myopathy and cardiomyopathy. The survival time is severely reduced. Contrasting with the usual disease course, we report on a family with an exceptionally mild phenotype of DD despite having two potentially damaging LAMP2 mutations. Using RNA-Seq analysis, we showed that a c.65-2A>G splice site mutation results in the tissue-specific production of four different transcripts including the full-length mRNA in muscle tissue but not in leukocytes. We confirmed our results by immunohistochemistry and immunoblotting, showing the detection of LAMP2 protein only in muscle. The second mutation (c.586A>T, p.T196S) has been reported before to have an uncertain clinical significance. In our patients, however, neither of the two mutations seem to have a high enough functional impact to cause a severe phenotype. Overall, our study reveals that alternative splicing is a potential mechanism in DD with underlying splice site mutations of the LAMP2 gene in order to rescue the full-length mRNA. Moreover, our report of a mild phenotype complements the DD spectrum, which is of great importance for a rare disease suspected to be underdiagnosed.


Assuntos
Estudos de Associação Genética , Doença de Depósito de Glicogênio Tipo IIb/genética , Proteína 2 de Membrana Associada ao Lisossomo/genética , Mutação , Sítios de Splice de RNA , Adulto , Feminino , Doença de Depósito de Glicogênio Tipo IIb/patologia , Humanos , Immunoblotting , Imuno-Histoquímica , Proteína 2 de Membrana Associada ao Lisossomo/química , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/química , Estudos Retrospectivos , Análise de Sequência de RNA , Transcrição Gênica
3.
Clin Neuropathol ; 30(1): 3-10, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21176711

RESUMO

Mutations in the microtubule-associated tau (MAPT) gene are associated clinically with frontotemporal dementia with or without supranuclear palsy, corticobasal syndrome or parkinsonism. Here we present clinical, neuropathological, genetic and biochemical data on a patient with an A152T variation in exon 7 of MAPT. A 63-year-old man presented with memory disturbance and later speech disorder, followed by progressive dementia and terminally myoclonus together with periodic sharp waves in EEG. Duration of illness was 5 years. Similar neuropsychiatric symptoms were reported in the patient's father. Neuropathological evaluation revealed neuronal loss mainly in the frontal and temporal cortices and substantia nigra. Abundant phospho-tau immunoreactive thread-like structures and diffuse staining of neuronal cytoplasm predominated in the frontal and temporal cortex, and hippocampus. There was a lack of astrocytic plaques and tufted astrocytes, and only a moderate number of oligodendroglial coiled bodies were seen. Tau pathology was characterized by the 4R tau isoform; immunoblot revealed bands at 64 and 68 kDa, and ultrastructure of filaments was compatible with twisted ribbons. Pathogenic mutations have not been reported in exon 7. Our observation of an apparently familial disorder with a novel neuropathological phenotype suggests a possible pathogenic role of this MAPT gene variation, which might be different from mutations affecting the microtubule binding.


Assuntos
Éxons/genética , Mutação/genética , Tauopatias/genética , Proteínas tau/genética , Eletroencefalografia , Humanos , Masculino , Microtúbulos/patologia , Pessoa de Meia-Idade , Fenótipo , Tauopatias/metabolismo , Tauopatias/patologia , Proteínas tau/metabolismo
4.
Cancer Gene Ther ; 24(1): 38-44, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27982017

RESUMO

Extracellular vesicles (EVs) are considered as important mediators of intercellular communication, which carry a diverse repertoire of genetic information between cells. This feature of EVs can be used and improved to advance their therapeutic potential. We have previously shown that genetically engineered EVs carrying the suicide gene mRNA and protein-cytosine deaminase (CD) fused to uracil phosphoribosyltransferase (UPRT)-inhibited schwannoma tumor growth in vivo. To further examine whether this approach can be applied to other cancer types, we established a subcutaneous xenograft glioblastoma tumor model in mice, as glioblastoma represents the most common primary brain tumor, which is highly aggressive compared with the original schwannoma tumor model. U87-MG glioblastoma cells were implanted into the flanks of nude SCID mice, and the animals were intratumorally injected with the EVs isolated from the cells expressing EGFP or CD-UPRT. After the intraperitoneal administration of the prodrug 5-fluorocytosine, the tumor growth was assessed by regular caliper measurements. Our data revealed that the treatment with the CD-UPRT-enriched EVs significantly reduced the tumor growth in mice. Taken together, our findings suggest that EVs uploaded with therapeutic CD-UPRT mRNA/protein may be a useful tool for glioblastoma treatment.


Assuntos
Sistemas de Liberação de Medicamentos , Vesículas Extracelulares/metabolismo , Técnicas de Transferência de Genes , Genes Transgênicos Suicidas , Glioblastoma/genética , Glioblastoma/metabolismo , RNA Mensageiro , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Transporte Biológico , Ciclo Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Modelos Animais de Doenças , Feminino , Expressão Gênica , Engenharia Genética , Glioblastoma/patologia , Glioblastoma/terapia , Humanos , Camundongos , Camundongos SCID , Pentosiltransferases/genética , Pentosiltransferases/metabolismo , Pró-Fármacos/farmacologia , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Cancer Res ; 57(7): 1228-32, 1997 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9102203

RESUMO

Ovarian cancer cells frequently metastasize by implanting onto the peritoneal mesothelial lining of the abdominal cavity. Data obtained from in vitro adhesion studies have suggested a possible role for the CD44 molecule in this process. The purpose of the present study was to determine the in vivo role of CD44 in ovarian cancer metastasis by using a nude mouse xenograft model of peritoneal implantation. Three groups of 10 athymic female nude mice each received an i.p. inoculum of 10 x 10(6) cells from a CD44-positive human ovarian cancer cell line (36M2) in the presence of either anti-D144 antibody (Ab; nonreactive IgG1), anti-DF3 Ab (reactive IgG1 Ab that does not inhibit in vitro binding), or neutralizing anti-CD44 Ab (IgG1). The number of peritoneal and diaphragmatic implants at 5 weeks for anti-D144 and anti-DF3-treated groups was 103 +/- 17 and 120 +/- 20, respectively (mean +/- SE; P > 0.2). In contrast, animals treated with anti-CD44 Ab experienced a significant reduction in the number of tumor implants (35 +/- 4; P < 0.002). Anti-CD44 Ab was not inhibitory to the growth of 36M2 cells in vitro and did not inhibit s.c. tumor growth in vivo, suggesting that the observed effect was related to inhibition of peritoneal implantation. These data suggest that the CD44 molecule plays an important in vivo role in ovarian cancer cell implantation and that strategies to inhibit CD44 function may represent a novel approach to limiting the intra-abdominal spread of this highly lethal tumor.


Assuntos
Receptores de Hialuronatos/fisiologia , Neoplasias Ovarianas/metabolismo , Neoplasias Peritoneais/secundário , Animais , Anticorpos Monoclonais/farmacologia , Adesão Celular , Divisão Celular , Diafragma , Feminino , Humanos , Immunoblotting , Imuno-Histoquímica , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/prevenção & controle , Neoplasias Cutâneas/prevenção & controle , Neoplasias Cutâneas/secundário , Transplante Heterólogo , Células Tumorais Cultivadas
6.
Cancer Res ; 59(9): 2121-6, 1999 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10232598

RESUMO

The BAX proapoptotic protein is capable of inducing cell death either directly, through its effects on mitochondrial function, or indirectly, by lowering the apoptotic threshold in response to certain chemotherapy agents. In this study, we tested the hypothesis that selective expression of BAX in human ovarian cancer through adenoviral gene transfer might represent a novel approach to eradicating tumor cells in vivo. Two constructs were prepared using replication-deficient adenoviral vectors containing either the cDNA for beta-galactosidase (Ad.DF3.betaGAL) or hemagglutinin (HA)-tagged BAX (Ad.DF3.BAX) under the control of the DF3 promoter. The DF3 promoter was used to confer tumor-specific gene expression in view of its restricted pattern of expression in the majority of human ovarian cancers and its limited expression in normal peritoneal mesothelial cells. In vitro infection of up to seven different epithelial cancer cell lines with Ad.DF3.betaGAL or Ad.DF3.BAX resulted in expression of either beta-galactosidase activity or HA-BAX protein, respectively, which was highly correlated with DF3 levels. Furthermore, infection with Ad.DF3.BAX was capable of highly selective cytotoxicity of DF3-positive ovarian cancer clonogenic cells in vitro. The effect of i.p. administration of Ad.DF3.BAX was also assessed in nude mice inoculated with the DF3-positive 36M2 human ovarian cancer cell line. Expression of either beta-galactosidase activity (after Ad.DF3.betaGAL treatment) or HA-BAX transcripts (after Ad.DF3.BAX treatment) was restricted to tumor tissue in vivo. Importantly, administration of Ad.DF3.BAX on days 2 and 3 after tumor inoculation was capable of eradicating >99% of tumor implants. These results demonstrate the feasibility of tumor selective expression of a proapoptotic protein such as BAX through adenoviral gene transfer.


Assuntos
Antígenos de Neoplasias/genética , Apoptose/genética , Regulação Neoplásica da Expressão Gênica , Terapia Genética , Neoplasias Ovarianas/patologia , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas/fisiologia , Adenocarcinoma/patologia , Adenovírus Humanos/genética , Animais , Neoplasias da Mama/patologia , Estudos de Viabilidade , Feminino , Genes Reporter , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Humanos , Injeções Intraperitoneais , Óperon Lac , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/terapia , Regiões Promotoras Genéticas , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Células Tumorais Cultivadas/metabolismo , Proteína X Associada a bcl-2 , beta-Galactosidase/análise , beta-Galactosidase/genética
7.
Cancer Res ; 58(21): 4776-81, 1998 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9809975

RESUMO

SW626 cells that overexpress BAX are sensitized to the cytotoxic effects of paclitaxel and vincristine. It has been assumed that BAX mediates these effects through its ability to alter mitochondrial function, specifically by promoting the release of cytochrome c and facilitating the mitochondrial permeability transition. However, we have found that several early paclitaxel-mediated events are enhanced in SW626 transfectants that overexpress BAX, including G2-M-phase arrest, tubulin polymerization, and BCL-2 phosphorylation. We now demonstrate that these seemingly disparate effects are explained by an enhanced accumulation of paclitaxel in BAX-overexpressing cells, an effect due to diminished drug efflux. In contrast, drug efflux is increased in cells that do not overexpress BAX, resulting in low intracellular paclitaxel levels and relative resistance to the effects of this drug. Drug efflux in SW626 cells is mediated by a verapamil-inhibitable, non-MDR-1, non-MRP-1 transporter whose function or expression may be inhibited by BAX. These data suggest that stable transfectants that overexpress BAX may be sensitized to apoptotic cell death through a novel mechanism involving the enhancement of intracellular levels of naturally occurring toxins such as alkaloid derivatives.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Apoptose/efeitos dos fármacos , Paclitaxel/farmacocinética , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas/fisiologia , Transportadores de Cassetes de Ligação de ATP/fisiologia , Feminino , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Paclitaxel/farmacologia , Transfecção , Células Tumorais Cultivadas , Verapamil/farmacologia , Vimblastina/farmacocinética , Proteína X Associada a bcl-2
8.
Oncogene ; 14(23): 2753-8, 1997 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-9190890

RESUMO

The p53 protein is known to play a central role in mediating G1 arrest or apoptosis in response to ionizing radiation in some cell types. It has been proposed that the link between p53 and induction of apoptosis is provided in part by p53-mediated upregulation of BAX. In this study, we used the human SW626 ovarian cancer cell line, which lacks functional p53, to further investigate the relationship between wildtype p53, BAX, and apoptosis. SW626 cells expressing a temperature sensitive (ts) p53 mutant did not undergo G1 arrest or apoptosis and did not exhibit enhanced sensitivity to radiation at the permissive temperature of 32 degrees C. The tsp53 protein was functional in these cells as evidenced by rapid induction of p21 at 32 degrees C, but not at 37 degrees C. Interestingly, restoration of wildtype p53 function at 32 degrees C was not associated with BAX upregulation. In addition, stable overexpression of BAX in SW626 cells was not capable of enhancing apoptotic cell death in response to radiation. Thus, failure of p53 to upregulate BAX is not the sole reason for its inability to promote radiation-induced apoptosis in SW626 cells. Taken together, our data suggest that neither p53 nor BAX upregulation is sufficient for the induction of apoptosis in response to genotoxic damage in some cell types.


Assuntos
Apoptose/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Apoptose/efeitos da radiação , Feminino , Fase G1 , Humanos , Neoplasias Ovarianas , Paclitaxel/farmacologia , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Tolerância a Radiação , Radiossensibilizantes/farmacologia , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/biossíntese , Proteína X Associada a bcl-2 , Proteína bcl-X
9.
Oncogene ; 17(19): 2419-27, 1998 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-9824152

RESUMO

Although paclitaxel is an important chemotherapy agent for the treatment of patients with epithelial ovarian cancer, its utility is significantly limited by the frequent development of drug resistance. Recent evidence suggests that resistance to chemotherapy may be partly related to defects in the apoptotic pathway. In this study we have investigated whether enhancement of apoptotic pathway function through stable expression of the BAD protein is capable of sensitizing human epithelial ovarian cancer cells to the effects of chemotherapy. Expression of HA-BAD in six separate clonal transfectants from two different ovarian cancer cell lines was found to significantly enhance the cytotoxic effects of paclitaxel, vincristine, and, to a lesser extent, etoposide. Enhancement of paclitaxel-induced apoptosis in HA-BAD-expressing clones was demonstrated by trypan blue exclusion, clonogenic cell assay, and flow cytometric evaluation. Importantly, this effect was associated with binding of HA-BAD to BCL-xL and concomitant disruption of BAX:BCL-xL interaction. Taken together, these data suggest that the development of small molecules which mimic the effects of BAD may represent a new class of drugs capable of preventing or reversing resistance to chemotherapy agents such as paclitaxel.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/fisiologia , Proteínas de Transporte/fisiologia , Resistencia a Medicamentos Antineoplásicos , Oncogenes , Neoplasias Ovarianas/patologia , Paclitaxel/farmacologia , Animais , Líquido Ascítico/citologia , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Células Clonais/efeitos dos fármacos , DNA de Neoplasias/análise , Células Epiteliais/metabolismo , Feminino , Humanos , Camundongos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/metabolismo , Ovário/citologia , Ovário/metabolismo , Proteínas Recombinantes de Fusão/fisiologia , Transfecção , Células Tumorais Cultivadas/efeitos dos fármacos , Proteína de Morte Celular Associada a bcl
10.
J Clin Oncol ; 13(8): 1912-21, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7543560

RESUMO

PURPOSE: CD44 is a hyaluronic acid receptor that exists as a standard 90-kd form (CD44S) as well as several CD44 variant isoforms produced through alternative splicing. Expression of CD44 variants is associated with clinically aggressive behavior in some human tumors. The purpose of the present study is to define the expression of CD44 variant isoforms in ovarian cancer and to investigate whether the expression of these molecules is associated with adverse prognosis. MATERIALS AND METHODS: Six specimens of normal ovarian surface epithelium (NOSE) and 31 separate cases of newly diagnosed ovarian cancer were studied by a combination of reverse-transcription polymerase chain reaction (RT-PCR) and immunoperoxidase staining. Clinical correlation was made between CD44 variant expression and stage (I/II v III/IV), residual disease (< or = 2.0- v > 2.0-cm mass), age (< or = 65 v > 65 years), histology (papillary serous v other), grade, and survival. RESULTS: RT-PCR analysis revealed that NOSE predominantly expressed transcripts for CD44S, as well as a restricted pattern of transcripts characteristic of CD44 splice variants. CD44S and CD44 variant exon nine sequences (CD44-9v) were focally expressed in one of two NOSE specimens examined by immunoperoxidase staining. In comparison, the majority (71%) of ovarian cancer specimens expressed a complex pattern of CD44 splice variants by RT-PCR analysis. Immunoperoxidase studies revealed that the majority of ovarian cancer specimens expressed both CD44S and CD44-9v, whereas expression of sequences from variant exons 3, 4, and 6 was uncommon. There was no association between CD44 variant expression (transcript or protein) and stage, residual disease, age, histology, grade, or survival. CONCLUSION: Expression of CD44S and CD44-9v is a common feature of epithelial ovarian cancer cells. The lack of a significant association between CD44 variant expression and prognosis suggests that other factors may be more important in determining the clinical behavior of this disease.


Assuntos
Proteínas de Transporte/metabolismo , Cistadenocarcinoma Papilar/imunologia , Neoplasias Ovarianas/imunologia , Receptores de Superfície Celular/metabolismo , Receptores de Retorno de Linfócitos/metabolismo , Adenocarcinoma de Células Claras/imunologia , Adulto , Idoso , Sequência de Bases , Proteínas de Transporte/genética , Epitélio/imunologia , Feminino , Humanos , Receptores de Hialuronatos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Dados de Sequência Molecular , Ovário/imunologia , Reação em Cadeia da Polimerase/métodos , Prognóstico , Receptores de Superfície Celular/genética , Receptores de Retorno de Linfócitos/genética , Transcrição Gênica
11.
J Clin Oncol ; 16(8): 2583-90, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9704707

RESUMO

PURPOSE: Expression of the pro-apoptotic protein BAX sensitizes ovarian cancer cell lines to paclitaxel in vitro by enhancing the pathway of programmed cell death. The present study was performed to determine the relationship between BAX expression and clinical outcome in 45 patients with newly diagnosed ovarian cancer. METHODS: BAX protein expression was analyzed by immunohistochemistry, and its relationship with clinical outcome was determined. Assessment of BAX mRNA transcript levels and mutational analysis of the BAX coding region were also performed. RESULTS: BAX protein was expressed at high levels (defined as > or = 50% of tumor cells positive) in tumor tissue from 60% of newly diagnosed patients. All patients whose tumors expressed high levels of BAX achieved a complete response (CR) to first-line chemotherapy that contained paclitaxel plus a platinum analogue, compared with 57% of patients in the low-BAX group (P = .036). After a median follow-up of 1.9 years, the median disease-free survival (DFS) of patients in the high-BAX group has not been reached, compared with a median DFS of 1.1 years for low-BAX expressors (P = .0061). BAX retained independent prognostic significance in multivariate analysis when corrected for stage and histology. BAX mRNA transcripts were easily detected in samples with low BAX protein expression, and no BAX mutations were identified. CONCLUSION: The correlation between high BAX levels and improved clinical outcome suggests that an intact apoptotic pathway is an important determinant of chemoresponsiveness in ovarian cancer patients who receive paclitaxel.


Assuntos
Carcinoma/patologia , Neoplasias Ovarianas/patologia , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas/análise , Antineoplásicos Fitogênicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/química , DNA Complementar/genética , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Neoplasias Ovarianas/química , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/administração & dosagem , Prognóstico , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/análise , Análise de Sequência de DNA , Proteína X Associada a bcl-2
12.
Oncogene ; 34(14): 1790-8, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-24858044

RESUMO

miR-200a has been implicated in the pathogenesis of meningiomas, one of the most common central nervous system tumors in humans. To identify how miR-200a contributes to meningioma pathogenesis at the molecular level, we used a comparative protein profiling approach using Gel-nanoLC-MS/MS and identified approximately 130 dysregulated proteins in miR-200a-overexpressing meningioma cells. Following the bioinformatic analysis to identify potential genes targeted by miR-200a, we focused on the non-muscle heavy chain IIb (NMHCIIb), and showed that miR-200a directly targeted NMHCIIb. Considering the key roles of NMHCIIb in cell division and cell migration, we aimed to identify whether miR-200a regulated these processes through NMHCIIb. We found that NMHCIIb overexpression partially rescued miR-200a-mediated inhibition of cell migration, as well as cell growth in vitro and in vivo. Moreover, siRNA-mediated silencing of NMHCIIb expression resulted in a similar migration phenotype in these cells and inhibited meningioma tumor growth in mice. Taken together, these results suggest that NMHCIIb might serve as a novel therapeutic target in meningiomas.


Assuntos
Neoplasias Meníngeas/patologia , Meningioma/patologia , MicroRNAs/genética , Cadeias Pesadas de Miosina/genética , Miosina não Muscular Tipo IIB/genética , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Meníngeas/genética , Meningioma/genética , Camundongos , Camundongos Nus , Cadeias Pesadas de Miosina/antagonistas & inibidores , Cadeias Pesadas de Miosina/biossíntese , Transplante de Neoplasias , Miosina não Muscular Tipo IIB/antagonistas & inibidores , Miosina não Muscular Tipo IIB/biossíntese , Interferência de RNA , RNA Interferente Pequeno , Transplante Heterólogo
13.
J Neuropathol Exp Neurol ; 60(5): 449-61, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11379820

RESUMO

Neuropathologists use anti-glial fibrillary acidic protein (GFAP) antibodies as specific markers for glial cells, and neurobiologists use GFAP for targeting transgenes to glial cells. Since GFAP has also been detected in non-glial cells, we systematically analyzed GFAP expression in human and murine non-CNS tissues using a panel of anti-GFAP antibodies. In human tissues we confirm previously observed GFAP expression in Schwann cells, myoepithelial cells, and chondrocytes, and show for the first time GFAP expression in fibroblasts of epiglottic and auricular perichondrium, ligamentum flavum, and cardiac valves. In mice we show GFAP expression in Schwann cells, bone marrow stromal cells, chondrocytes, and in fibroblasts of dura mater, skull and spinal perichondrium, and periosteum, connective stroma of oral cavity, dental pulp, and cardiac valves. Anti-GFAP immunoblotting of human non-CNS tissues reveals protein bands with a molecular mass ranging between approximately 35 and approximately 42 kDa. In GFAP-v-src transgenic mice, whose oncogenic v-src transgene transforms GFAP expressing cells, non-CNS tumors originate from fibroblasts. We conclude that human and murine fibroblasts can express GFAP in vivo. The somatic distribution of GFAP expressing fibroblasts indicates origin from the neural crest. Development of non-CNS tumors from fibroblasts in GFAP-v-src mice functionally confirms GFAP expression in these cells.


Assuntos
Fibroblastos/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Animais , Proteína Glial Fibrilar Ácida/genética , Humanos , Immunoblotting , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos/genética , Distribuição Tecidual
14.
Eur J Cancer ; 38(3): 393-400, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11818205

RESUMO

DNA topoisomerase IIalpha (Topo IIalpha) is linked to tumour cell growth and chemoresistance. We examined immunohistochemically Topo IIalpha expression levels in a series of 36 consecutive paediatric optic pathway glioma (OPG) patients. Topo IIalpha labelling index (LI) ranged from 0.0 to 11.6 and was significantly associated with patient age, with higher levels of Topo IIalpha in children < or = 3 years (P=0.031). Topo IIalpha expression did not correlate with patient survival. Topo IIalpha LI was not significantly increased in specimens of repeat surgery. Topo IIalpha LI closely correlated with MIB-1 LI (R=0.781, P<0.001). We conclude that Topo IIalpha expression correlates with tumour cell proliferation in paediatric OPGs. Assessment of cell proliferation, however, does not assist in refining prognostic predictions. Enhanced Topo IIalpha expression in children < or = 3.0 years suggests that Topo IIalpha-interfering anticancer compounds for adjuvant treatment of OPGs may be of particular benefit to young children.


Assuntos
DNA Topoisomerases Tipo II/metabolismo , Glioma do Nervo Óptico/metabolismo , Adolescente , Antígenos de Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Criança , Pré-Escolar , Estudos de Coortes , Proteínas de Ligação a DNA , Progressão da Doença , Feminino , Seguimentos , Humanos , Imuno-Histoquímica/métodos , Lactente , Imageamento por Ressonância Magnética/métodos , Masculino , Glioma do Nervo Óptico/tratamento farmacológico , Glioma do Nervo Óptico/cirurgia , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Tomografia Computadorizada por Raios X/métodos
15.
Biochem Pharmacol ; 37(14): 2833-8, 1988 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-2840079

RESUMO

Murine neuroblastoma clone N1E-115 possesses receptors that specifically bind the tridecapeptide neurotensin, mediate the formation of intracellular cyclic GMP, and stimulate inositol phospholipid hydrolysis. These cells also rapidly degrade neurotensin in a sequential fashion. We studied the effect of prolonged exposure of cells to neurotensin on subsequent neurotensin receptor-mediated intracellular cyclic GMP formation under conditions that prevented degradation of this peptide [J. A. Gilbert and E. Richelson, Soc. Neurosci. Abstr. 12, 762 (1986)]. Neurotensin receptor-mediated cyclic GMP formation in neuroblastoma clone N1E-115 was decreased following prolonged exposure of intact cells to nondegraded neurotensin. The time course of this desensitization was very rapid; the maximal effect on cyclic GMP production (reduction to 10-30% of control values) occurred within 5 min of exposure of intact cells to neurotensin. This desensitization was homologous, as cells desensitized by neurotensin demonstrated no decrease in their cyclic GMP response to angiotensin II (1 microM) or bradykinin (10 nM). Neurotensin preincubation with intact N1E-115 cells for increasing lengths of time caused time-dependent shifts to the right of the dose-response curve and reductions in the maximum cyclic GMP response. Desensitization was reversible, but resensitization was a slower process than desensitization: full recovery of cyclic GMP production required incubation of the desensitized cells for at least 10 min at 37 degrees. From binding studies with [3H]neurotensin, we found that both the apparent equilibrium dissociation constant, KD, and the maximum number of receptor sites, Bmax, for this radioligand were decreased significantly (P less than 0.05) for completely desensitized cells from those values for control cells. These data suggest that desensitization of the neurotensin receptor involved an uncoupling of the pathway of events connecting receptor activation to intracellular cyclic GMP formation; complete desensitization involved both the apparent loss of neurotensin receptors on the cellular surface and the increase in affinity of the remaining receptors for the agonist. This decrease in Bmax is more likely to be a result of intracellular sequestration of recyclable NT receptors than of true down-regulation due to the rapid resensitization seen for the NT-mediated biological response.


Assuntos
GMP Cíclico/biossíntese , Neuroblastoma/metabolismo , Receptores de Neurotransmissores/fisiologia , Animais , Relação Dose-Resposta a Droga , Camundongos , Neurotensina/farmacologia , Receptores Adrenérgicos beta/análise , Receptores de Neurotensina , Receptores de Neurotransmissores/análise , Células Tumorais Cultivadas
17.
Clin Neuropathol ; 21(5): 220-31, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12365725

RESUMO

Myofibrillar or desmin-related myopathies encompass neuromuscular disorders with abnormal deposits of desmin and myofibrillar alterations. We report 3 unrelated patients presenting with proximal and distal myopathy, and, as a unique congenital syndrome, diffusely distributed myopathy, osteoporosis and myopia. Muscle biopsies shared cytoplasmic inclusions, rimmed vacuoles, and ragged-red-like fibers. Sarcoplasmic inclusions, either plaque-like or amorphous, strongly immunoreacted on dystrophin and variably for desmin, alphaB crystallin and ubiquitin. Cyclin-dependent kinases CDK1, CDK2 and CDK5 were overexpressed in affected fibers. Ultrastructurally, focal myofibrillar disruption was accompanied by tubulo-filamentous inclusions in one case and abundant glycogen and enlarged mitochondria displaying respiratory chain dysfunction at biochemistry in another case. Molecular analysis of the alphaB crystallin gene coding sequence and exons 4, 5 and 6 of the desmin gene did not reveal any mutation. The morphologic denominator of hyaline structures and areas of myofibrillar destruction occurs in heterogeneous conditions and may overlap with features of inclusion body myopathy and mitochondrial myopathy.


Assuntos
Desmina/genética , Desmina/ultraestrutura , Doenças Musculares/genética , Doenças Musculares/patologia , Miofibrilas/patologia , Miofibrilas/ultraestrutura , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Miofibrilas/genética
18.
Oncogene ; 33(39): 4778-85, 2014 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-24166506

RESUMO

Minichromosome maintenance (MCM) proteins are key elements that function as a part of the pre-replication complex to initiate DNA replication in eukaryotes. Consistent with their roles in initiating DNA replication, overexpression of MCM family members has been observed in several malignancies. Through bioinformatic analysis of The Cancer Genome Atlas's data on glioblastoma multiforme (GBM), we found that the genomic region containing MCM7 gene was amplified in more than 80% of the present cases. To validate this finding and to identify the possible contribution of the remaining members of the MCM family to GBM progression, we used quantitative real-time PCR to analyze the gene expression profiles of all MCM family members in Grade IV (GBM) tissue samples and observed a significant upregulation in GBM samples compared with normal white matter tissues. In addition, we compared the observed gene expression profiles with those of Grade II and Grade III astrocytoma samples and determined that the observed upregulation was restricted and specific to Grade IV. MCM7 was the most upregulated gene in the gene set we analyzed, and therefore we wanted to identify the role of MCM7 in GBM progression. We determined that siRNA-mediated knockdown of MCM7 expression reduced GBM cell proliferation and also inhibited tumor growth in both xenograft and orthotopic mouse models of GBM. Taken together, our data suggest that MCM7 can be a potential prognostic marker and a novel therapeutic target in GBM therapy.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Componente 7 do Complexo de Manutenção de Minicromossomo/genética , Animais , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Glioblastoma/patologia , Camundongos , Camundongos Nus , Componente 7 do Complexo de Manutenção de Minicromossomo/metabolismo , Transplante de Neoplasias , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Carga Tumoral
20.
J Neurol Neurosurg Psychiatry ; 77(3): 413-6, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16484658

RESUMO

We report the case of a 28 year old man who had received a cadaverous dura mater graft after a traumatic open skull fracture with tearing of the dura at the age of 5 years. A clinical suspicion of Creutzfeldt-Jakob disease (CJD) was confirmed by a brain biopsy 5 months prior to death and by autopsy, thus warranting the diagnosis of iatrogenic CJD (iCJD) according to WHO criteria. Immunohistochemistry showed widespread cortical depositions of disease associated prion protein (PrP(sc)) in a synaptic pattern, and western blot analysis identified PrP(sc) of type 2A according to Parchi et al. Surprisingly, we found Alzheimer-type senile plaques and cerebral amyloid angiopathy in widespread areas of the brain. Plaque-type and vascular amyloid was immunohistochemically identified as deposits of beta-A4 peptide. CERAD criteria for diagnosis of definite Alzheimer's disease (AD) were met in the absence of neurofibrillar tangles or alpha-synuclein immunoreactive inclusions. There was no family history of AD, CJD, or any other neurological disease, and genetic analysis showed no disease specific mutations of the prion protein, presenilin 1 and 2, or amyloid precursor protein genes. This case represents (a) the iCJD case with the longest incubation time after dural grafting reported so far, (b) the youngest documented patient with concomitant CJD and Alzheimer-type neuropathology to date, (c) the first description of Alzheimer-type changes in iCJD, and (d) the second case of iCJD in Austria. Despite the young patient age, the Alzheimer-type changes may be an incidental finding, possibly related to the childhood trauma.


Assuntos
Doença de Alzheimer/patologia , Síndrome de Creutzfeldt-Jakob/patologia , Osso Frontal/lesões , Doença Iatrogênica , Fraturas Cranianas/cirurgia , Adolescente , Adulto , Biópsia , Encéfalo/patologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Dura-Máter/lesões , Dura-Máter/patologia , Dura-Máter/transplante , Evolução Fatal , Seguimentos , Osso Frontal/patologia , Humanos , Masculino , Exame Neurológico , Complicações Pós-Operatórias/patologia , Fraturas Cranianas/patologia
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