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1.
Ann Oncol ; 34(3): 300-314, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36494005

RESUMO

BACKGROUND: New precision medicine therapies are urgently required for glioblastoma (GBM). However, to date, efforts to subtype patients based on molecular profiles have failed to direct treatment strategies. We hypothesised that interrogation of the GBM tumour microenvironment (TME) and identification of novel TME-specific subtypes could inform new precision immunotherapy treatment strategies. MATERIALS AND METHODS: A refined and validated microenvironment cell population (MCP) counter method was applied to >800 GBM patient tumours (GBM-MCP-counter). Specifically, partition around medoids (PAM) clustering of GBM-MCP-counter scores in the GLIOTRAIN discovery cohort identified three novel patient clusters, uniquely characterised by TME composition, functional orientation markers and immune checkpoint proteins. Validation was carried out in three independent GBM-RNA-seq datasets. Neoantigen, mutational and gene ontology analysis identified mutations and uniquely altered pathways across subtypes. The longitudinal Glioma Longitudinal AnalySiS (GLASS) cohort and three immunotherapy clinical trial cohorts [treatment with neoadjuvant/adjuvant anti-programmed cell death protein 1 (PD-1) or PSVRIPO] were further interrogated to assess subtype alterations between primary and recurrent tumours and to assess the utility of TME classifiers as immunotherapy biomarkers. RESULTS: TMEHigh tumours (30%) displayed elevated lymphocyte, myeloid cell immune checkpoint, programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 transcripts. TMEHigh/mesenchymal+ patients featured tertiary lymphoid structures. TMEMed (46%) tumours were enriched for endothelial cell gene expression profiles and displayed heterogeneous immune populations. TMELow (24%) tumours were manifest as an 'immune-desert' group. TME subtype transitions upon recurrence were identified in the longitudinal GLASS cohort. Assessment of GBM immunotherapy trial datasets revealed that TMEHigh patients receiving neoadjuvant anti-PD-1 had significantly increased overall survival (P = 0.04). Moreover, TMEHigh patients treated with adjuvant anti-PD-1 or oncolytic virus (PVSRIPO) showed a trend towards improved survival. CONCLUSIONS: We have established a novel TME-based classification system for application in intracranial malignancies. TME subtypes represent canonical 'termini a quo' (starting points) to support an improved precision immunotherapy treatment approach.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Microambiente Tumoral , Recidiva Local de Neoplasia , Imunoterapia/métodos , Neoplasias Encefálicas/tratamento farmacológico
2.
Public Health ; 149: 74-80, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28575751

RESUMO

OBJECTIVES: Comparison of outcomes for cancer patients discussed and not discussed at a multidisciplinary meeting (MDM). STUDY DESIGN: Retrospective analysis of the association of MDM discussion with survival. METHODS: All newly diagnosed cancer patients from 2009 to 2012, presenting to a large regional cancer service in South West Victoria, Australia (620 colorectal, 657 breast, 593 lung and 511 haematological) were recorded and followed up to 5 years after diagnosis. Treatment patterns and survival of patients whose treatment was discussed at an MDM compared to those who were not, were explored. RESULTS: The proportion of patients presented to an MDM within 60 days after diagnosis was 56% (n = 366) for breast cancer, 59% (n = 363) for colorectal cancer, 27% (n = 137) for haematological malignancies and 60% (n = 355) for lung cancer. Seventy-three percent (n = 886) of patients discussed at an MDM had their tumour stage recorded in their medical records while only 52% (n = 604) of patients not discussed had their tumour stage recorded (P < 0.01). We found for haematological and lung cancer patients that those presented to an MDM prior to treatment had a significant reduction in mortality (lung cancer hazard ratio [HR] 0.62, 95% confidence interval [CI] 0.50-0.76, P < 0.01) (haematological cancer HR 0.58, 95% CI 0.35-0.96, P = 0.03) compared to patients whose cases were not discussed at an MDM after adjusting for the potential cofounders of age, stage, comorbidities and treatment. This was not the case for colorectal and breast cancer patients where there was no significant difference. CONCLUSION: MDM discussion has been recommended as best practice in the management of cancer patients, however, from a public health perspective this creates potential issues around access and resources. It is likely that MDM presentation patterns and outcomes across tumour streams are linked in complex ways. We believe that our data would demonstrate that these patterns differ across tumour streams and that more detailed work is required to better allocate relatively scarce and potentially costly MDM resources to tumour streams and patient groups that may get the most benefit.


Assuntos
Processos Grupais , Comunicação Interdisciplinar , Neoplasias/terapia , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Vitória/epidemiologia
3.
Eur J Cancer ; 51(14): 2049-57, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26208461

RESUMO

AIMS: The aims of this analysis were to examine levels of unmet needs and depression among carers of people newly diagnosed with cancer and to identify groups who may be at higher risk, by examining relationships with demographic characteristics. METHODS: One hundred and fifty dyads of people newly diagnosed with cancer and their carers, aged 18 years and older, were recruited from four Australian hospitals. People with cancer receiving adjuvant cancer treatment with curative intent, were eligible to participate. Carers completed the Supportive Care Needs Survey-Partners & Caregivers (SCNS-P&C45), and both carers and patients completed the Centre of Epidemiologic-Depression Scale (CES-D). RESULTS: Overall, 57% of carers reported at least one, 37% at least three, 31% at least five, and 15% at least 10 unmet needs; the most commonly endorsed unmet needs were in the domains of information and health care service needs. Thirty percent of carers and 36% of patients were at risk of clinical depression. A weak to moderate positive relationship was observed between unmet needs and carer depression (r=0.30, p<0.001). Carer levels of unmet needs were significantly associated with carer age, hospital type, treatment type, cancer type, living situation, relationship status (in both uni- and multi-factor analysis); person with cancer age and carer level of education (in unifactor analysis only); but not with carer gender or patient gender (in both uni- and multi-factor analyses). CONCLUSION: Findings highlight the importance of developing tailored programmes to systematically assist carers who are supporting patients through the early stages of cancer treatment.


Assuntos
Cuidadores/psicologia , Depressão/psicologia , Necessidades e Demandas de Serviços de Saúde , Avaliação das Necessidades , Neoplasias/psicologia , Neoplasias/terapia , Adaptação Psicológica , Adulto , Idoso , Idoso de 80 Anos ou mais , Efeitos Psicossociais da Doença , Depressão/diagnóstico , Depressão/prevenção & controle , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Medição de Risco , Fatores de Risco , Inquéritos e Questionários , Vitória , Adulto Jovem
4.
Biofouling ; 26(5): 539-53, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20526914

RESUMO

This study used a specially designed MAGPLATE system to quantify the en route survivorship and post-voyage recovery of biofouling assemblages subjected to short voyages (< 12 h) across a range of vessel speeds (slow, medium, fast; in the range 4.0-21.5 knots). The effect of hull location (bow, amidships and stern) was also examined. While no significant differences were evident in en route survivorship of biofouling organisms amongst hull locations, biofouling cover and richness were markedly reduced on faster vessels relative to slower craft. Therefore, the potential inoculum size of non-indigenous marine species and richness is likely to be reduced for vessels that travel at faster speeds (> 14 knots), which is likely to also reduce the chances of successful introductions. Despite this, the magnitude of introductions from biofouling on fast vessels can be considered minor, especially for species richness where 90% of source-port species were recorded at destinations.


Assuntos
Incrustação Biológica , Invertebrados/classificação , Invertebrados/crescimento & desenvolvimento , Navios , Animais , Biodiversidade , Biologia Marinha/métodos , Nova Zelândia , Dinâmica Populacional , Especificidade da Espécie
5.
Biofouling ; 26(5): 555-66, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20526980

RESUMO

The present study tested two diver-operated rotating brush systems, coupled with suction and collection capabilities, to determine their efficacy in the management of vessel biofouling. Both rotating brush systems proved effective (> 80%) in removing low-to-moderate levels of fouling from flat and curved experimental surfaces (Perspex plates). However, performance was generally poorer at removing more advanced levels of fouling. In particular, mature calcareous organisms were relatively resistant to the rotating brushes, with a high proportion (up to 50%) remaining on plates following treatment. On average, > 95% of defouled material was collected and retained by both systems. The amount of lost material generally increased when treating curved plates with increasing biomass, whereas the material lost from flat plates was typically less and remained relatively constant throughout the trials. The majority (> 80%) of fouling not captured by the systems was crushed by the brushes (ie non-viable). However, a diverse range of viable organisms (eg barnacles and hydroids) was lost to the environment during the defouling trials. When defouling a vessel, unintentional detachment of fouling organisms is likely to be high through physical disturbance by divers operating the devices and by associated equipment (eg hoses). Furthermore, residual biosecurity risks are also likely to remain due to diver error, persistent fouling remaining on treated surfaces and the inaccessibility of niche areas to the brush systems. To address these limitations, further research into alternative treatment methods is required.


Assuntos
Incrustação Biológica/prevenção & controle , Invertebrados/crescimento & desenvolvimento , Biologia Marinha/métodos , Navios , Animais , Briozoários/crescimento & desenvolvimento , Eucariotos/crescimento & desenvolvimento , Invertebrados/classificação , Biologia Marinha/instrumentação , Poliquetos/crescimento & desenvolvimento , Rotação , Propriedades de Superfície
6.
Mar Pollut Bull ; 60(9): 1533-40, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20553694

RESUMO

Vessels found contaminated with biofouling non-indigenous marine species are predominantly removed from the water and treated in vessel maintenance facilities (i.e., slipways, travel lifts and dry-docks). Using pre-fouled settlement plates to simulate a vessel's removal from the water for treatment, we demonstrate that a range of mobile organisms (including non-indigenous marine species) may be lost to the marine environment as a consequence of this process. We also determined that different levels of biofouling (primary, secondary and tertiary) and emersion durations (0.5, 5 and 15 min) affected the abundance and composition of mobile taxa lost to the marine environment. Primary biofouling plates lost 3.2% of total animals, secondary plates lost 19.8% and tertiary plates lost 8.2%, while hanging duration had only minor effects. The results suggest that removing vessels contaminated with biofouling non-indigenous marine species from the water for treatment may not be as biosecure as is currently recognised.


Assuntos
Incrustação Biológica/prevenção & controle , Espécies Introduzidas , Invertebrados/fisiologia , Biologia Marinha/métodos , Navios/métodos , Animais
7.
Biofouling ; 26(1): 1-13, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20390551

RESUMO

This study experimentally determined the effect of different vessel voyage speeds (5, 10 and 18 knots = 2.6, 5.1 and 9.3 ms(-1), respectively) and morphological characteristics including growth form (solitary or colonial), profile (erect or encrusting) and structure (soft, hard or flexible) on the survival of a range of common biofouling organisms. A custom built hydrodynamic keel attached to the bottom of a 6 m aluminium powerboat was used to subject pre-fouled settlement plates for this purpose. Vessel speeds of 5 and 10 knots had little effect on the species richness of biofouling assemblages tested, however richness decreased by 50% following 18 knots treatments. Species percentage cover decreased with increasing speed across all speed treatments and this decrease was most pronounced at 10 and 18 knots, with cover reduced by 24 and 85% respectively. Survival was greatest for organisms with colonial, encrusting, hard and/or flexible morphological characteristics, and this effect increased with increasing speed. This study suggests that there is predictive power in forecasting future introductions if we can understand the extent to which such traits explain the world-wide distributions of non-indigenous species. Future introductions are a certainty and can only provide an increasing source of new information on which to test the validity of these predications.


Assuntos
Incrustação Biológica , Invertebrados/crescimento & desenvolvimento , Biologia Marinha/métodos , Navios , Animais , Invertebrados/classificação , Dinâmica Populacional , Especificidade da Espécie
8.
Br J Cancer ; 99(2): 294-304, 2008 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-18594532

RESUMO

TRAIL/Apo-2L has shown promise as an anti-glioma drug, based on investigations of TRAIL sensitivity in established glioma cell lines, but it is not known how accurately TRAIL signalling pathways of glioma cells in vivo are reproduced in these cell lines in vitro. To replicate as closely as possible the in vivo behaviour of malignant glioma cells, 17 early passage glioma cell lines and 5 freshly resected gliomas were exposed to TRAIL-based agents and/or chemotherapeutic drugs. Normal human hepatocytes and astrocytes and established glioma cell lines were also tested. Cross-linked TRAIL, but not soluble TRAIL, killed both normal cell types and cells from three tumours. Cells from only one glioma were killed by soluble TRAIL, although only inefficiently. High concentrations of cisplatin were lethal to glioma cells, hepatocytes and astrocytes. Isolated combinations of TRAIL and chemotherapy drugs were more toxic to particular gliomas than normal cells, but no combination was generally selective for glioma cells. This study highlights the widespread resistance of glioma cells to TRAIL-based agents, but suggests that a minority of high-grade glioma patients may benefit from particular combinations of TRAIL and chemotherapy drugs. In vitro sensitivity assays may help identify effective drug combinations for individual glioma patients.


Assuntos
Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Glioma/tratamento farmacológico , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Adulto , Idoso , Antineoplásicos/administração & dosagem , Astrócitos/efeitos dos fármacos , Carboplatina/administração & dosagem , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Ensaios de Seleção de Medicamentos Antitumorais , Etoposídeo/administração & dosagem , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioma/patologia , Hepatócitos/efeitos dos fármacos , Humanos , Lomustina/administração & dosagem , Masculino , Glicoproteínas de Membrana/administração & dosagem , Pessoa de Meia-Idade , Procarbazina/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Ligante Indutor de Apoptose Relacionado a TNF/administração & dosagem , Temozolomida , Fator de Necrose Tumoral alfa/administração & dosagem , Vincristina/administração & dosagem
9.
Mar Pollut Bull ; 54(7): 875-86, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17498747

RESUMO

A total of 150 different organisms, including one plant species and 12 animal phyla were identified from sea-chests of 42 vessels visiting or operating in New Zealand between May 2000 and November 2004. Forty-nine percent of organisms were sessile, 42% mobile adults and the remaining 9% sedentary. Decapods were the most represented group with 19 species present among 79% of vessels. Forty percent of organisms were indigenous to New Zealand, 15% introduced, 10% non-indigenous, and 35% of unknown origin. Sea-chests have the potential to (1) transfer non-indigenous organisms between countries across oceanic boundaries; and (2) disperse both indigenous and introduced organisms domestically. The occurrence of adult mobile organisms is particularly significant and indicates that sea-chests may be of greater importance than ballast water or hull fouling for dispersing certain marine species. These findings emphasise the need to assess and manage biosecurity risks for entire vessels rather than different mechanisms (i.e., ballast water, hull fouling, sea-chests, etc.) in isolation.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecossistema , Monitoramento Ambiental/métodos , Biologia Marinha/métodos , Animais , Monitoramento Ambiental/legislação & jurisprudência , Geografia , Humanos , Nova Zelândia , Oceanos e Mares , Avaliação de Programas e Projetos de Saúde , Medição de Risco/métodos , Fatores de Tempo
11.
Intern Med J ; 36(5): 302-7, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16650195

RESUMO

The optimal management of adolescent and young adult cancer has been the subject of vigorous debate in paediatric and adult cancer community for many years. This debate is rapidly coming to the boil. There is international recognition that not only is cancer in young people on the rise but also that improvements in outcomes of cancer in young people lag well behind the advances that have been achieved for both children and older adults in the past 30 years. The underlying problems appear to relate to a complex set of interactions between the health-care system and the prevalence of cancer in this age group and the unique psychosocial and educational needs of this population. This article explores why we should be concerned about Australian health outcomes in this group and considers how best we might respond to these concerns.


Assuntos
Neoplasias/psicologia , Neoplasias/terapia , Adolescente , Adulto , Fatores Etários , Austrália , Ensaios Clínicos como Assunto , Humanos , Incidência , Neoplasias/epidemiologia , Autonomia Pessoal , Isolamento Social , Falha de Tratamento
12.
J Pediatr Surg ; 39(12): 1787-90, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15616930

RESUMO

PURPOSE: The aim of this study was to investigate children presenting with malignant pelvic tumors obstructing the upper urinary tract. METHODS: Seventeen children with upper urinary tract obstruction by a malignant tumor were reviewed. A nephrostomy tube or Double J (DJ) stent was inserted into each obstructed urinary system and removed after tumor shrinkage and/or hydronephrosis regression. RESULTS: There were 9 boys and 8 girls in the study; the mean age and median follow-up were 5.7 years and 2.5 years, respectively. The most common obstructing tumor was rhabdomyosarcoma. Twelve children underwent diversion by nephrostomy tubes and 3 by DJ stents; 2 patients underwent resection of the tumors with ureteroureterostomy. Complications after the insertion of the stents included febrile urinary tract infections (UTI) or pyelonephritis in 4 of the children with DJ stents. In the nephrostomy group, febrile UTI developed in 3 and the tube fell out in 1, and was blocked in another. Of the 17 children, 9 have no evidence of disease, 2 are currently under treatment, and 6 died of cancer. CONCLUSIONS: The prognosis of children with malignant pelvic tumor obstructing the upper urinary system justifies urgent and optimal upper tract diversion, enabling chemotherapy to be started immediately.


Assuntos
Neoplasias Pélvicas/complicações , Obstrução Ureteral/etiologia , Obstrução Ureteral/cirurgia , Derivação Urinária , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino
13.
Cell Death Differ ; 11(12): 1309-16, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15543163

RESUMO

A genetically defined pathway orchestrates the removal of 131 of the 1090 somatic cells generated during the development of the hermaphrodite nematode Caenorhabditis elegans. Regulation of apoptosis is highly evolutionarily conserved and the nematode cell death pathway is a valuable model for studying mammalian apoptotic pathways, the dysregulation of which can contribute to numerous diseases. The nematode caspase CED-3 is ultimately responsible for the destruction of worm cells in response to apoptotic signals, but it must first be activated by CED-4. CED-9 inhibits programmed cell death and considerable data have demonstrated that CED-9 can directly bind and inhibit CED-4. However, it has been suggested that CED-9 may also directly inhibit CED-3. In this study, we used a yeast-based system and biochemical approaches to explore this second potential mechanism of action. While we confirmed the ability of CED-9 to inhibit CED-4, our data argue that CED-9 can not directly inhibit CED-3.


Assuntos
Apoptose/fisiologia , Proteínas de Caenorhabditis elegans/metabolismo , Caspases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/fisiologia , Animais , Proteínas Reguladoras de Apoptose , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Caspases/química , Caspases/genética , Ativação Enzimática/fisiologia , Retroalimentação Fisiológica/fisiologia , Regulação Fúngica da Expressão Gênica/fisiologia , Técnicas In Vitro , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2
15.
Cell Death Differ ; 9(12): 1311-20, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12478468

RESUMO

This study characterized the ability of a new member of the p35 family, p49, to inhibit a number of mammalian and insect caspases. p49 blocked apoptosis triggered by treatment with Fas ligand (FasL), Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) or ultraviolet (UV) radiation but provided negligible protection against apoptosis induced by the chemotherapeutic drug cisplatin. The caspase cleavage site in p49 was determined, and mutation of the P1 residue of this site abolished the ability of p49 to inhibit caspases, implying that p49 inhibits caspases through an analogous suicide-substrate mechanism to p35. Unlike p35, p49 inhibited the upstream insect caspase DRONC.


Assuntos
Apoptose/genética , Proteínas de Drosophila , Células Eucarióticas/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Transativadores/metabolismo , Proteínas Virais/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Proteínas Reguladoras de Apoptose , Inibidores de Caspase , Caspases/genética , Caspases/metabolismo , Células Cultivadas , Cisplatino/farmacologia , Drosophila melanogaster , Células Eucarióticas/efeitos dos fármacos , Células Eucarióticas/efeitos da radiação , Proteína Ligante Fas , Humanos , Proteínas Imediatamente Precoces/genética , Glicoproteínas de Membrana/farmacologia , Dados de Sequência Molecular , Mutação/genética , Saccharomyces cerevisiae , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Ligante Indutor de Apoptose Relacionado a TNF , Transativadores/genética , Fator de Necrose Tumoral alfa/farmacologia , Raios Ultravioleta , Proteínas Virais/genética
17.
Oncogene ; 20(41): 5789-98, 2001 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-11593384

RESUMO

FasL and TNF-related apoptosis-inducing ligand (TRAIL) belong to a subgroup of the TNF superfamily which induce apoptosis by binding to their death domain containing receptors. In the present study we have utilized a panel of seven cell lines derived from human malignant gliomas to characterize molecular pathways through which FasL and TRAIL induce apoptosis in sensitive glioma cells and the mechanisms of resistance in cell lines which survive the death stimuli. Our findings indicate that FADD and Caspase-8 are essential for FasL and TRAIL mediated apoptosis in glioma cells. One sensitive cell line (D270) can be protected from FasL and TRAIL induced death by anti-apoptotic Bcl-2 family members while another (D645) cannot, implying that these lines may represent glioma examples of type II and type I cells respectively. For the first time we demonstrate resistance to FasL but not to TRAIL within the one glioma cell line. Furthermore, we report distinct mechanisms of resistance within different glioma lines, including downregulation of Caspase-8 in U373MG. Cycloheximide sensitized four of the resistant cell lines suggesting the presence of labile inhibitors. None of the known apoptosis inhibitors examined accounted for the observed resistance, suggesting novel inhibitors may exist in glioma cells.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Apoptose/fisiologia , Glioma/fisiopatologia , Glicoproteínas de Membrana/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose , Proteínas de Transporte/metabolismo , Caspase 3 , Caspase 8 , Caspase 9 , Caspases/metabolismo , Cisplatino/farmacologia , Cicloeximida/farmacologia , Resistencia a Medicamentos Antineoplásicos , Ativação Enzimática , Proteína Ligante Fas , Proteína de Domínio de Morte Associada a Fas , Glioma/metabolismo , Humanos , Ligantes , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Ligante Indutor de Apoptose Relacionado a TNF , Células Tumorais Cultivadas/efeitos dos fármacos , Proteína bcl-X
18.
Neuro Oncol ; 3(4): 229-40, 2001 10.
Artigo em Inglês | MEDLINE | ID: mdl-11584892

RESUMO

Fas (APO-1/CD95/TNFRSF6) is a member of the tumor necrosis/nerve growth factor receptor family that signals apoptotic cell death in sensitive cells. Expression of Fas and its agonistic ligand (FasL/TNFSF6) was investigated in ex vivo pediatric brain tumor specimens of various histologic types. Fas expression was identified in all of the 18 tumors analyzed by flow cytometry and immunohistochemistry. FasL expression was identified in most of the 13 tumors analyzed by both Western analysis and immunohistochemistry. Nine of these tumor specimens were treated with either the agonistic anti-Fas antibody (APO-1) in combination with protein A or FasL in short-term cytotoxicity assays. Sensitivity to apoptosis induced by the topoisomerase II inhibitor, etoposide, was also assessed. Despite the presence of Fas, all the specimens analyzed demonstrated a high degree of resistance to Fas-mediated apoptosis. These 9 specimens also showed a high degree of resistance to etoposide. Only 2 of the 9 specimens were susceptible to etoposide-induced cell death, whereas only 3 were sensitive to Fas-mediated apoptosis. One brain tumor was sensitive to both Fas ligation and etoposide treatment. This contrasted with the high degree of susceptibility to both etoposide- and Fas-induced apoptosis observed in the reference Jurkat cell line. The results suggest that Fas expression may be a general feature of tumors of the CNS and that a significant degree of resistance to Fas-mediated apoptosis may exist in ex vivo pediatric brain tumor specimens.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/química , Resistencia a Medicamentos Antineoplásicos , Glicoproteínas de Membrana/análise , Proteínas de Neoplasias/análise , Receptor fas/análise , Adolescente , Animais , Antineoplásicos/farmacologia , Astrocitoma/química , Sobrevivência Celular , Criança , Pré-Escolar , Colorimetria , Meios de Cultivo Condicionados , DNA Complementar/genética , Etoposídeo/farmacologia , Proteína Ligante Fas , Feminino , Ganglioglioma/química , Germinoma/química , Glioblastoma/química , Humanos , Lactente , Células Jurkat/efeitos dos fármacos , Masculino , Meduloblastoma/química , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/fisiologia , Camundongos , Proteínas de Neoplasias/fisiologia , Neuroblastoma/patologia , Tumores Neuroectodérmicos Primitivos/química , Glândula Pineal/química , Pinealoma/química , Proteínas Recombinantes de Fusão/fisiologia , Transfecção , Células Tumorais Cultivadas , Receptor fas/fisiologia
19.
Apoptosis ; 6(5): 331-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11483856

RESUMO

We have reconstituted the Apaf-1-activated apoptosis mechanism in Sacchromyces cerevisiae such that the presence of a constitutively active form of Apaf-1 together with both Caspase-9 and Caspase-3 results in yeast death. This system is a good model of the Apaf-1-activated pathway in mammalian cells: MIHA (XIAP/hILP), and to a lesser degree MIHB (c-IAP1/HIAP2) and MIHC (c-IAP-2/HIAP1) can inhibit caspases in this system, and protection by IAPs (inhibitor of apoptosis) can be abrogated by coexpression of the Drosophila pro-apoptotic proteins HID and GRIM or the mammalian protein DIABLO/Smac. Using this system we demonstrate that unlike DIABLO/Smac, other proteins which interact with mammalian IAPs (TAB-1, Zap-1, Traf-1 and Traf-2) do not act to antagonise IAP- mediated caspase inhibition.


Assuntos
Apoptose , Inibidores de Caspase , Proteínas de Drosophila , Proteínas/antagonistas & inibidores , Proteínas/fisiologia , Saccharomyces cerevisiae/genética , Animais , Fator Apoptótico 1 Ativador de Proteases , Proteínas de Transporte/fisiologia , Caspase 3 , Caspase 9 , Caspases/fisiologia , Proteínas Inibidoras de Apoptose , Proteínas Mitocondriais/fisiologia , Neuropeptídeos/fisiologia , Proteínas/genética , Saccharomyces cerevisiae/citologia , Transfecção , Proteínas Virais/fisiologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X
20.
J Pediatr Hematol Oncol ; 23(9): 572-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11902299

RESUMO

BACKGROUND: The purpose of this study was to examine the clinical and radiologic response to carboplatin by children with progressive optic/thalamic gliomas. PATIENTS AND METHODS: Between July 1997 and July 1999, 12 consecutive children were treated with monthly carboplatin for progressive optic/thalamic gliomas. RESULTS: Five children have completed 12 cycles of carboplatin and five children are currently receiving treatment. Two children had progressive disease noted both clinically and radiologically. Nine children have stable radiologic disease and one child has had a partial radiologic response to chemotherapy. Eight children have had regular visual assessments. Four children (three with stable radiology and one with a partial radiologic response) have had improvement in their vision. Three children with radiologically stable disease have had no change in vision. One child has had deterioration in vision despite radiologically stable disease. CONCLUSIONS: The results suggest that the clinical response of optic/thalamic gliomas to carboplatin, as measured by visual acuity and visual fields, may be better than predicted by radiologic assessment. These data suggest that a prospective clinical study is warranted of the role of carboplatin in children with progressive optic/thalamic gliomas and visual impairment.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Carboplatina/uso terapêutico , Glioma/tratamento farmacológico , Quiasma Óptico , Neoplasias do Nervo Óptico/tratamento farmacológico , Tálamo , Transtornos da Visão/etiologia , Adolescente , Anemia/induzido quimicamente , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/efeitos adversos , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/cirurgia , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Criança , Pré-Escolar , Terapia Combinada , Progressão da Doença , Feminino , Glioma/complicações , Glioma/cirurgia , Humanos , Infusões Intravenosas , Masculino , Neurofibromatose 1/complicações , Neutropenia/induzido quimicamente , Quiasma Óptico/cirurgia , Neoplasias do Nervo Óptico/complicações , Neoplasias do Nervo Óptico/cirurgia , Indução de Remissão , Estudos Retrospectivos , Tálamo/cirurgia , Trombocitopenia/induzido quimicamente , Resultado do Tratamento , Acuidade Visual , Campos Visuais
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