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1.
Mol Clin Oncol ; 4(4): 487-491, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27073647

RESUMO

Brain metastases are the most common intracranial tumors in adults, accounting for over half of all lesions. Whole-brain radiation therapy (WBRT) has been a cornerstone in the management of brain metastases for decades. Recently, stereotactic radiosurgery (SRS) has been considered as a definitive or postoperative approach instead of WBRT, to minimize the risk of cognitive impairment that may be associated with WBRT. This is the case report of a 74-year-old female patient who was diagnosed with lung cancer in November, 2002, and histopathologically confirmed brain metastases in January, 2005. The patient received 5 treatments with Gamma Knife SRS for recurring brain metastases between 2005 and 2014. The patient remains highly functional, with stable intracranial disease at 10 years since first developing brain metastases, and with stable lung disease. Therefore, Gamma Knife SRS is a safe and effective treatment modality for patients with recurrent intracranial metastases, with durable local control and minimal cognitive impairment.

2.
PLoS One ; 8(3): e59588, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23527225

RESUMO

Although cyclin dependent kinase (CDK)-2 is known to be dispensable for the growth of most tumors, it is thought to be important for the proliferation of melanoma cells, where its expression is controlled by the melanocyte-lineage specific transcription factor MITF. Treatment of a panel of melanoma cells with the CDK inhibitor dinaciclib led to a concentration-dependent inhibition of growth under both 2D adherent and 3D organotypic cell culture conditions. Dinaciclib targeted melanoma cell lines regardless of cdk2 or MITF levels. Inhibition of growth was associated with a rapid induction of G2/M cell arrest and apoptosis. Treatment of human melanoma mouse xenografts with dinaciclib led to tumor regression associated with reduced retinoblastoma protein phosphorylation and Bcl-2 expression. Further mechanistic studies revealed that dinaciclib induces p53 expression whilst simultaneously downregulating the expression of the anti-apoptotic factors Mcl-1 and XIAP. To clarify the role of p53 activation in the dinaciclib-induced cell death, we generated melanoma cell lines in which p53 expression was knocked down using a shRNA lentiviral vector. Knockdown of p53 completely abolished the induction of apoptosis seen following dinaciclib treatment as shown by a lack of annexin-V staining and caspase-3 cleavage. Altogether, these data show that dinaciclib induces apoptosis in a large panel of melanoma cell lines through a mechanism requiring p53 expression.


Assuntos
Apoptose/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Melanoma/tratamento farmacológico , Compostos de Piridínio/farmacologia , Transdução de Sinais/fisiologia , Proteína Supressora de Tumor p53/metabolismo , 2-Hidroxipropil-beta-Ciclodextrina , Animais , Western Blotting , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Óxidos N-Cíclicos , Citometria de Fluxo , Humanos , Indolizinas , Melanoma/metabolismo , Camundongos , Camundongos SCID , Esferoides Celulares/efeitos dos fármacos , beta-Ciclodextrinas
3.
Pan Afr Med J ; 6: 3, 2010 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-21436946

RESUMO

Teledermatology is essentially "dermatology at a distance", using one of many communication technologies to expand the reach of a dermatologist to those in need of their specialized knowledge. Most international teledermatology is store-and-forward in nature, a method in which images are stored on a computer and then transmitted electronically to a consulting dermatologist. This system is more convenient and less costly than real-time teledermatology. This review will focus on several of the store-and-forward teledermatology systems being developed and utilized successfully internationally. This discussion of "who" is practicing teledermatology is not comprehensive, but attempts to show some of the breadth of teledermatology practice around the world, including government national health plans, commercial endeavors, and charitable work by individuals and institutions. The goal in many instances is to provide better health outcomes through increased access, efficiency, and/or cost-effectiveness. More studies ultimately need to be conducted to develop a more comprehensive and sustainable model for teledermatology.


Assuntos
Redes de Comunicação de Computadores , Consulta Remota/métodos , Dermatopatias/diagnóstico , Redes de Comunicação de Computadores/economia , Redes de Comunicação de Computadores/instrumentação , Análise Custo-Benefício , Dermatologia/tendências , Países em Desenvolvimento , Humanos , Cooperação Internacional , Avaliação de Processos e Resultados em Cuidados de Saúde , Satisfação do Paciente , Consulta Remota/economia , Consulta Remota/instrumentação
4.
Mol Cancer Ther ; 7(9): 2876-83, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18790768

RESUMO

Recent studies have shown that there is a considerable heterogeneity in the response of melanoma cell lines to MEK and BRAF inhibitors. In the current study, we address whether dysregulation of cyclin-dependent kinase 4 (CDK4) and/or cyclin D1 contribute to the BRAF inhibitor resistance of melanoma cells. Mutational screening identified a panel of melanoma cell lines that harbored both a BRAF V600E mutation and a CDK4 mutation: K22Q (1205Lu), R24C (WM39, WM46, and SK-Mel-28), and R24L (WM902B). Pharmacologic studies showed that the presence of a CDK4 mutation did not alter the sensitivity of these cell lines to the BRAF inhibitor. The only cell line with significant BRAF inhibitor resistance was found to harbor both a CDK4 mutation and a CCND1 amplification. Array comparative genomic hybridization analysis showed that CCND1 was amplified in 17% of BRAF V600E-mutated human metastatic melanoma samples, indicating the clinical relevance of this finding. As the levels of CCND1 amplification in cell lines are lower than those seen in clinical specimens, we overexpressed cyclin D1 alone and in the presence of CDK4 in a drug-sensitive melanoma line. Cyclin D1 overexpression alone increased resistance and this was enhanced when cyclin D1 and CDK4 were concurrently overexpressed. In conclusion, increased levels of cyclin D1, resulting from genomic amplification, may contribute to the BRAF inhibitor resistance of BRAF V600E-mutated melanomas, particularly when found in the context of a CDK4 mutation/overexpression.


Assuntos
Ciclina D1/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Imidazóis/farmacologia , Melanoma/genética , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Substituição de Aminoácidos/efeitos dos fármacos , Sequência de Bases , Linhagem Celular Tumoral , Ciclina D1/genética , Quinase 4 Dependente de Ciclina/genética , Análise Mutacional de DNA , Amplificação de Genes/efeitos dos fármacos , Ácido Glutâmico/genética , Humanos , Melanoma/metabolismo , Dados de Sequência Molecular , Valina/genética
5.
DNA Cell Biol ; 23(4): 239-47, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15142381

RESUMO

New and effective approaches for inflammatory diseases based on novel mechanisms of action are needed. One potential source of anti-inflammatory drugs exists among viruses. Viruses have evolved to infect, replicate within, and kill human cells through diverse mechanisms. They accomplish this fact by finding ways to out with the host's complex immune machinery. It is possible that the viral proteins and pathways involved in the downregulation of host immune function during infection can be exploited as a therapeutic in diseases that result in the overactivity of the immune system. Indeed, the human immunodeficiency virus type 1 (HIV-1) protein, Vpr, affects cells in a number of ways that may prove useful for exploitation for the treatment of inflammatory diseases. Vpr has effects on T-cell proliferation, cytokine production, chemokine production, and Nuclear Factor kappa B (NF-kappaB)-mediated transcription. Importantly, it has been observed that Vpr downregulates NF-kappaB and the production of pro-inflammatory cytokines such as TNF-alpha, and IL-12. These activities are worthy of further examination for control of hyperinflammatory and hyperproliferative conditions.


Assuntos
Regulação para Baixo , Produtos do Gene vpr/uso terapêutico , HIV-1/fisiologia , Inflamação/terapia , NF-kappa B/metabolismo , Quimiocinas/metabolismo , Produtos do Gene vpr/metabolismo , Produtos do Gene vpr/fisiologia , Humanos , Interleucina-12/metabolismo , Modelos Biológicos , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Produtos do Gene vpr do Vírus da Imunodeficiência Humana
6.
J Biol Chem ; 277(40): 37820-31, 2002 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-12095993

RESUMO

Human immunodeficiency virus, type 1 (HIV-1), vpr gene encodes a 14-kDa virion-associated protein, which exhibits significant effects on human cells. One important property of Vpr is its ability to induce apoptosis during infection. Apoptotic induction is likely to play a role in the pathogenesis of AIDS. However, the pathway of apoptosis is not clearly defined. In this report we investigate the mechanism of apoptosis induced by HIV-1 Vpr using a Vpr pseudotype viral infection system or adeno delivery of Vpr in primary human lymphoid cells and T-cells. With either vector, HIV-1 Vpr induced cell cycle arrest at the G(2)/M phase and apoptosis in lymphoid target cells. Furthermore, we observed that with both vectors, caspase 9, but not caspase 8, was activated following infection of human peripheral blood mononuclear cell with either Vpr-positive HIV virions or adeno-delivered Vpr. Activation of the caspase 9 pathway resulted in caspase 3 activation and apoptosis in human primary cells. These effects were coincident with the disruption of the mitochondrial transmembrane potential and induction of cytochrome c release by Vpr. The Vpr-induced signaling pathway did not induce CD95 or CD95L expression. Bcl-2 overexpressing cells succumb to Vpr-induced apoptosis. These studies illustrate that Vpr induces a mitochondria-dependent apoptotic pathway that is distinct from apoptosis driven by the Fas-FasL pathway.


Assuntos
Apoptose/fisiologia , Caspases/metabolismo , Ciclo Celular/fisiologia , Produtos do Gene vpr/fisiologia , HIV-1/genética , Neutrófilos/fisiologia , Linfócitos T/fisiologia , Anexina A5/farmacologia , Apoptose/efeitos dos fármacos , Caspase 9 , Linhagem Celular , Células HeLa , Humanos , Células Jurkat , Neutrófilos/virologia , Linfócitos T/virologia , Vírion/fisiologia , Produtos do Gene vpr do Vírus da Imunodeficiência Humana
7.
Oncogene ; 21(30): 4613-25, 2002 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-12096338

RESUMO

The targeted delivery of genes whose products arrest the cell cycle and/or induce apoptosis represent an important tool for the understanding and controlling forms of unregulated cell growth. The vpr gene product of HIV-1 has been reported to interfere with cell growth and induce apoptosis, but the mechanism of its action is not clearly understood. In order to study these important properties of Vpr, we created a recombinant adenovirus H5.010CMV-vpr (adCMV-vpr) as a tool to deliver the vpr gene to various cell lines to examine its biology. Vpr protein expression was confirmed by Western blot analysis in adCMV-vpr infected cells. We tested the effects of adCMV-vpr on cell growth of several tumor cell lines. Infection of both p53 positive and p53 deficient tumor cell lines with adCMV-vpr resulted in dramatic induction of cell death in short-term assays. We observed that apoptosis was induced through the mitochondrial pathway as we observed changes in the cytochrome c content accompanied by caspase 9 activation. As Bcl-2 is reported to interfere with apoptosis through the mitochondrial pathway, we examined the effect of adCMV-vpr in Bcl-2 over expressing cell lines. We observed that Bcl-2 overexpression does not inhibit adCMV-vpr induced apoptosis. The properties of adCMV-vpr inducing apoptosis through caspase 9 in a p53 pathway independent manner suggest that this is an important reagent. Such a vector may give insight into approaches designed to limit the growth of pathogenic human cells.


Assuntos
Apoptose , Caspases/metabolismo , Produtos do Gene vpr/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adenoviridae/genética , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 9 , Ciclo Celular , Tamanho Celular , Sobrevivência Celular , Ativação Enzimática , Citometria de Fluxo , Deleção de Genes , Expressão Gênica , Produtos do Gene vpr/genética , Vetores Genéticos/genética , Células HeLa , Humanos , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução Genética , Transgenes/genética , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética
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