Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 108
Filtrar
1.
Harm Reduct J ; 16(1): 70, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842903

RESUMO

BACKGROUND: The twin problems of severe alcohol dependence and homelessness are associated with precarious living and multiple acute, social and chronic harms. While much attention has been focused on harm reduction services for illicit drug use, there has been less attention to harm reduction for this group. Managed alcohol programs (MAPs) are harm reduction interventions that aim to reduce the harms of severe alcohol use, poverty and homelessness. MAPs typically provide accommodation, health and social supports alongside regularly administered sources of beverage alcohol to stabilize drinking patterns and replace use of non-beverage alcohol (NBA). METHODS: We examined impacts of MAPs in reducing harms and risks associated with substance use and homelessness. Using case study methodology, data were collected from five MAPs in five Canadian cities with each program constituting a case. In total, 53 program participants, 4 past participants and 50 program staff were interviewed. We used situational analysis to produce a series of "messy", "ordered" and "social arenas" maps that provide insight into the social worlds of participants and the impact of MAPs. RESULTS: Prior to entering a MAP, participants were often in a revolving world of cycling through multiple arenas (health, justice, housing and shelters) where abstinence from alcohol is often required in order to receive assistance. Residents described living in a street-based survival world characterized by criminalization, unmet health needs, stigma and unsafe spaces for drinking and a world punctuated by multiple losses and disconnections. MAPs disrupt these patterns by providing a harm reduction world in which obtaining accommodation and supports are not contingent on sobriety. MAPs represent a new arena that focuses on reducing harms through provision of safer spaces and supply of alcohol, with opportunities for reconnection with family and friends and for Indigenous participants, Indigenous traditions and cultures. Thus, MAPs are safer spaces but also potentially spaces for healing. CONCLUSIONS: In a landscape of limited alcohol harm reduction options, MAPs create a new arena for people experiencing severe alcohol dependence and homelessness. While MAPs reduce precarity for participants, programs themselves remain precarious due to ongoing challenges related to lack of understanding of alcohol harm reduction and insecure program funding.


Assuntos
Alcoolismo/reabilitação , Redução do Dano , Pessoas Mal Alojadas , Adulto , Idoso , Alcoolismo/psicologia , Atitude Frente a Saúde , Canadá , Feminino , Pacientes Domiciliares/psicologia , Humanos , Masculino , Programas de Assistência Gerenciada , Pessoa de Meia-Idade , Pobreza , Apoio Social , Estereotipagem
2.
Ann Oncol ; 30(6): 927-933, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30903140

RESUMO

BACKGROUND: HER2-positive (+) breast cancers, defined by HER2 overexpression and/or amplification, are often addicted to HER2 to maintain their malignant phenotype. Yet, some HER2+ tumors do not benefit from anti-HER2 therapy. We hypothesize that HER2 amplification levels and PI3K pathway activation are key determinants of response to HER2-targeted treatments without chemotherapy. PATIENTS AND METHODS: Baseline HER2+ tumors from patients treated with neoadjuvant lapatinib plus trastuzumab [with endocrine therapy for estrogen receptor (ER)+ tumors] in TBCRC006 (NCT00548184) were evaluated in a central laboratory for HER2 amplification by fluorescence in situ hybridization (FISH) (n = 56). HER2 copy number (CN) and FISH ratios, and PI3K pathway status, defined by PIK3CA mutations or PTEN levels by immunohistochemistry were available for 41 tumors. Results were correlated with pathologic complete response (pCR; no residual invasive tumor in breast). RESULTS: Thirteen of the 56 patients (23%) achieved pCR. None of the 11 patients with HER2 ratio <4 and/or CN <10 achieved pCR, whereas 13/45 patients (29%) with HER2 ratio ≥4 and/or CN ≥10 attained pCR (P = 0.0513). Of the 18 patients with tumors expressing high PTEN or wild-type (WT) PIK3CA (intact PI3K pathway), 7 (39%) achieved pCR, compared with 1/23 (4%) with PI3K pathway alterations (P = 0.0133). Seven of the 16 patients (44%) with HER2 ratio ≥4 and intact PI3K pathway achieved pCR, whereas only 1/25 (4%) patients not meeting these criteria achieved pCR (P = 0.0031). CONCLUSIONS: Our findings suggest that there is a clinical subtype in breast cancer with high HER2 amplification and intact PI3K pathway that is especially sensitive to HER2-targeted therapies without chemotherapy. A combination of HER2 FISH ratio and PI3K pathway status warrants validation to identify patients who may be treated with HER2-targeted therapy without chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Receptor ErbB-2/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Feminino , Seguimentos , Amplificação de Genes , Humanos , Hibridização in Situ Fluorescente , Lapatinib/administração & dosagem , Terapia Neoadjuvante , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/genética , Indução de Remissão , Trastuzumab/administração & dosagem
3.
Oncogene ; 36(20): 2910-2918, 2017 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-27893709

RESUMO

Estrogen receptor α (ERα) is a master driver of a vast majority of breast cancers. Breast cancer cells often develop resistance to endocrine therapy via restoration of the ERα activity through survival pathways. Thus identifying the epigenetic activator of ERα that can be targeted to block ERα gene expression is a critical topic of endocrine therapy. Here, integrative genomic analysis identified MYST3 as a potential oncogene target that is frequently amplified in breast cancer. MYST3 is involved in histone acetylation via its histone acetyltransferase domain (HAT) and, as a result, activates gene expression by altering chromatin structure. We found that MYST3 was amplified in 11% and/or overexpressed in 15% of breast tumors, and overexpression of MYST3 correlated with worse clinical outcome in estrogen receptor+ (ER+) breast cancers. Interestingly, MYST3 depletion drastically inhibited proliferation in MYST3-high, ER+ breast cancer cells, but not in benign breast epithelial cells or in MYST3-low breast cancer cells. Importantly, we discovered that knocking down MYST3 resulted in profound reduction of ERα expression, while ectopic expression of MYST3 had the reversed effect. Chromatin immunoprecipitation revealed that MYST3 binds to the proximal promoter region of ERα gene, and inactivating mutations in its HAT domain abolished its ability to regulate ERα, suggesting MYST3 functioning as a histone acetyltransferase that activates ERα promoter. Furthermore, MYST3 inhibition with inducible MYST3 shRNAs potently attenuated breast tumor growth in mice. Together, this study identifies the first histone acetyltransferase that activates ERα expression which may be potentially targeted to block ERα at transcriptional level.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Epigênese Genética , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Histona Acetiltransferases/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Feminino , Técnicas de Silenciamento de Genes , Histona Acetiltransferases/genética , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Int J Cancer ; 131(10): 2215-22, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22618667

RESUMO

MiRNAs are a class of short, endogenous, single-stranded RNA molecules that play a role in the regulation of gene expression. They have been shown to modulate a number of cellular processes including cell differentiation, growth and apoptosis and as a result have been implicated in carcinogenesis. They are detectable in tumour tissue, and altered expression levels have been identified in various cancer types. Of interest, miRNAs have recently been detected and identified to be dysregulated in the circulation of patients with breast cancer. The fact that a minimally invasive test can distinguish the presence or absence of disease illustrates the immense potential these molecules hold as predictive markers. This review serves to identify those systemic miRNAs that are upregulated or downregulated in malignancy and how treatment impacts on their circulating levels. In addition, this review questions the source of these small molecules in the bloodstream and how they may possibly play a role in the future detection of cancer as either prognostic or predictive markers.


Assuntos
Biomarcadores Tumorais/genética , MicroRNAs/genética , Neoplasias/diagnóstico , Neoplasias/genética , Biomarcadores Tumorais/sangue , Humanos , MicroRNAs/sangue , Ácidos Nucleicos/sangue , Estabilidade de RNA
5.
Age Ageing ; 40(3): 330-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21345840

RESUMO

OBJECTIVE: to explore views on advance care planning in care homes for older people. DESIGN: qualitative exploration of views from care home staff and the family of residents in care homes for older people. SETTING: all care homes for the elderly in two London Boroughs. PARTICIPANTS: staff (care managers, nurses and care assistants), community nurses and families. METHODS: individual semi-structured interviews. RESULTS: themes of the analysis: (i) BENEFITS: staff and family revealed positive opinions towards advance care planning. Staff felt it provided choice for residents and encouraged better planning. (ii) Barriers: staff and families perceived residents as reluctant to discuss advance care planning. Some care assistants were reluctant to be involved. Furthermore, families and staff reported prevalence of dementia among residents as another barrier. Nurses and care managers identified both family involvement and unforeseen medical circumstances as problematic. (iii) Facilitators: (a) early initiation of discussions (b) family involvement to establish preferences (c) residents and staff being well-known to each other and (d) staff training, were perceived to facilitate ACP. CONCLUSIONS: overall, staff and families support the concept of ACP. Methods to overcome the identified barriers are required to embed ACP within end of life care in care homes.


Assuntos
Planejamento Antecipado de Cuidados , Atitude do Pessoal de Saúde , Família/psicologia , Planejamento de Assistência ao Paciente , Participação do Paciente/psicologia , Idoso , Comunicação , Instituição de Longa Permanência para Idosos , Humanos , Entrevistas como Assunto , Londres , Competência Mental , Casas de Saúde , Pesquisa Qualitativa
6.
Oncogene ; 30(6): 724-36, 2011 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-20890303

RESUMO

INT6/EIF3E has been implicated in breast tumorigenesis, but its functional activities remain poorly defined. We found that, repressing INT6 expression induced transformed properties in normal human mammary epithelium (MCF10A); in contrast, Int6 silencing induced apoptosis in HeLa cells. As in fission yeast, Int6 in human cells was required for assembly of active proteasomes. A reverse-phase protein array screen identified SRC3/AIB1 as one oncoprotein the level and stability of which increased when Int6 was silenced in MCF10A cells. Our data further show that Int6 binds SRC3 and its ubiquitin ligase Fbw7, thus perhaps mediating the interaction between SRC3-Fbw7 and proteasomes. Consistent with this, Int6 silencing did not increase SRC3 levels in HeLa cells, which have low Fbw7 levels. It is surprising that, however, polyubiquitylated proteins do not accumulate or may even decrease in Int6-silenced cells that contain defective proteasomes. Considering that decreased ubiquitin might explain this observation and that Int6 might control ubiquitin levels in its role as a subunit of eIF3 (eukaryote translation initiation factor 3), we found that silencing Int6 reduced monoubiquitin protein levels, which correlated with a shift of ubiquitin mRNAs from larger polysomes to non-translating ribosomes. In contrast, levels of many housekeeping proteins did not change. This apparent reduction in the translation of ubiquitin genes correlated with a modest reduction in protein synthesis rate and formation of large polysomes. To further determine whether Int6 can selectively control translation, we analyzed translation of different 5'-untranslated region reporters and found that indeed, loss of Int6 had differential effects on these reporters. Together the data suggest that Int6 depletion blocks ubiquitin-dependent proteolysis by decreasing both ubiquitin levels and the assembly of functional proteasome machinery, leading to accumulation of oncoproteins, such as SRC3 that can transform mammary epithelium. Our data also raise the possibility that Int6 can further fine-tune protein levels by selectively controlling translation of specific mRNAs.


Assuntos
Fator de Iniciação 3 em Eucariotos/metabolismo , Glândulas Mamárias Humanas/crescimento & desenvolvimento , Glândulas Mamárias Humanas/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Biossíntese de Proteínas , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Fator de Iniciação 3 em Eucariotos/genética , Proteínas F-Box/metabolismo , Proteína 7 com Repetições F-Box-WD , Inativação Gênica , Humanos , Coativador 3 de Receptor Nuclear/metabolismo , Polirribossomos/metabolismo , Ligação Proteica , Ribossomos/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
7.
J Neurosci Res ; 87(4): 956-63, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18951490

RESUMO

Antiglycolipid IgM antibodies are known to induce formation of "wide spaced" or "expanded" myelin, a distinctive form of dysmyelination characterized by a repeat period approximately two or three times normal, which is seen also in diseases, including multiple sclerosis. To determine whether an antibody directed against a myelin protein would cause equivalent pathology, we implanted O10 hybridoma cells into the spinal cord of adult or juvenile rats. O10 produces an IgM directed against PLP, the major protein of CNS myelin. Subsequent examination of the cords showed focal demyelination and remyelination. In addition, however, some juvenile cords, but none of the adult cords, displayed wide-spaced myelin with lamellae separated by an extracellular material comprising elements consistent with IgM molecules in appearance. Wide spacing tended to involve the outer layers of the sheath and in some cases alternated with normally spaced lamellae. A feature not seen previously consists of multiple expanded myelin lamellae in one sector of a sheath continuous with normally spaced lamellae in another, resulting in variation in sheath thickness around the axonal circumference. This uneven distribution of wide-spaced lamellae is most simply explained based on incorporation of IgM molecules into immature sheaths during myelin formation and implies a model of CNS myelinogenesis more complex than simple spiraling. The periaxonal space never displays widening of this kind, but the interface with adjacent myelin sheaths or oligodendrocytes may. Thus, wide spacing appears to require that IgM molecules bridge between two PLP-containing membranes and does not reflect the mere presence of immunoglobulin within the extracellular space.


Assuntos
Doenças Desmielinizantes/fisiopatologia , Imunoglobulina M/imunologia , Proteína Proteolipídica de Mielina/imunologia , Bainha de Mielina/fisiologia , Medula Espinal/fisiopatologia , Envelhecimento , Animais , Anticorpos , Linhagem Celular , Doenças Desmielinizantes/patologia , Hibridomas , Microscopia Eletrônica , Bainha de Mielina/ultraestrutura , Fotomicrografia , Ratos , Ratos Wistar , Medula Espinal/patologia
8.
Rheumatology (Oxford) ; 45(6): 741-5, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16403827

RESUMO

OBJECTIVES: Cardiovascular disease is a major cause of mortality and morbidity in patients with Takayasu's arteritis (TA). Increased arterial stiffness is an independent risk factor and predictor of cardiovascular mortality in a variety of diseases. Pulse wave velocity (PWV) and the augmentation index (AI) are used as clinical measurements of arterial stiffness. METHODS: Data are presented from 10 patients with TA and 11 normal controls obtained between 2000 and 2004. Arterial compliance was assessed non-invasively by measurement of PWV, using the Complior system, and calculation of the aortic AI. RESULTS: TA patients (mean age 40.8+/-13.2 yr) were compared with a control group of healthy women from a parallel study (mean age 32.3+/-5.5 yr). The mean carotid-femoral PWV (PWV-CF) was higher in TA patients (P = 0.03). In addition, both aortic AI derived from the radial artery (P = 0.002) and carotid AI (P = 0.03) were higher in TA patients compared with controls. PWV-CF did not correlate with CRP (r = - 0.23, P = 0.23) or ESR (r = - 0.19, P = 0.27). Similar results were obtained for the correlation of carotid-radial PWV with CRP (r = 0.15, P = 0.32) and ESR (r = 0.33, P = 0.14). CONCLUSIONS: Our data show that TA is associated with elevated arterial stiffness in the central aorta, which may persist when the disease is quiescent. These data suggest that PWV represents a means by which cardiovascular risk can be detected and monitored in TA, and highlights the importance of effective management of cardiovascular risk factors in these patients.


Assuntos
Artérias/fisiopatologia , Arterite de Takayasu/fisiopatologia , Adulto , Velocidade do Fluxo Sanguíneo , Sedimentação Sanguínea , Proteína C-Reativa/análise , Complacência (Medida de Distensibilidade) , Feminino , Humanos , Pessoa de Meia-Idade , Fluxo Pulsátil , Arterite de Takayasu/sangue , Resistência Vascular
9.
Endocr Relat Cancer ; 12 Suppl 1: S113-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16113087

RESUMO

De novo resistance to endocrine therapy is a near-universal feature of oestrogen receptor (ER)- negative breast cancer. Although many ER-positive breast cancers also show no response to tamoxifen or aromatase inhibitors on objective clinical grounds the large majority show reduced proliferation indicating that some oestrogen dependence is present in almost all ER-positive breast cancer. In neoadjuvant studies HER2 positivity is associated with poor response rates to tamoxifen but not aromatase inhibitors, consistent with preclinical models. Acquired resistance to tamoxifen is associated with decreases in ER positivity but most recurrent lesions remain ER-positive. A small proportion of these show increased HER2 expression and in these patients increased phospho-p38 may contribute to the tamoxifen-resistant phenotype. There is an unfortunate paucity of clinical and biological data on acquired resistance to aromatase inhibitors.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Tamoxifeno/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos , Estrogênios/metabolismo , Feminino , Humanos , Neoplasias Hormônio-Dependentes/metabolismo , Transdução de Sinais
10.
Neuropsychobiology ; 50(1): 10-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15179014

RESUMO

In healthy women, plasma norepinephrine (NE) has a cycle with the highest levels occurring at ovulation and early luteal phase. We examined plasma NE cyclicity in premenstrual syndrome (PMS) patients as compared to controls, its relation to estradiol (E(2)), progesterone (P), luteinizing hormone and follicle-stimulating hormone, and the correlation of these parameters with the PMS symptoms. Lack of NE cyclicity was observed in PMS patients. In controls, peak NE levels occurred at ovulation and early luteal phase. In PMS, serum E(2) was higher during the follicular phase, while P and gonadotrophins were higher especially at ovulation and the luteal phase. In the late luteal phase, E(2) levels were lower in PMS patients than in controls. A negative correlation was observed between the area under the curve for E(2) in the luteal phase and PMS somatic and mental scores. Plasma NE showed a negative correlation with abrupt mood swings, impatience, nervousness, tiredness, weakness, apathy, and headache. These data suggest that lack of NE cyclicity characterizes PMS, some symptoms being related to low E(2) levels during the late luteal phase and decreased noradrenergic activity at ovulation and the luteal phase.


Assuntos
Estradiol/sangue , Fase Folicular/fisiologia , Gonadotropinas/sangue , Fase Luteal/fisiologia , Norepinefrina/sangue , Síndrome Pré-Menstrual/fisiopatologia , Progesterona/sangue , Adulto , Afeto , Ansiedade , Estudos de Casos e Controles , Fadiga , Feminino , Cefaleia , Humanos , Periodicidade
11.
Clin Cancer Res ; 7(12 Suppl): 4338s-4342s; discussion 4411s-4412s, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11916222

RESUMO

Breast cancer development and progression are directly related to the effects of the female hormone estrogen. The nuclear receptor for estrogen (ER) functions as a transcription factor controlling estrogen-regulated genes. Receptor conformation on ligand binding, its interaction with various coregulators, and response elements in the promoter region of target genes all contribute to the net estrogenic effects in a cell. ER is an important diagnostic and therapeutic target in breast cancer. Various polypeptide growth factors and their membrane receptors also contribute to breast cancer development and progression. Pathways mediating cell survival, cell proliferation, and response to stress not only generate signals through various protein kinase pathways to enhance cell survival and proliferation, but these pathways also interact with ERs. Kinases in the growth factor cascade can phosphorylate and activate ER, and ER in turn activates and augments signaling through the growth factor pathways. Signaling through the growth factor pathways may contribute to hormonal resistance states by ligand-independent activation of ER. Targeting growth factor pathways, in addition to ER, is a developing strategy that hypothetically may represent optimal therapy by preventing the development of resistance to endocrine therapy.


Assuntos
Neoplasias da Mama/metabolismo , Receptores de Estrogênio/metabolismo , Animais , Feminino , Substâncias de Crescimento/metabolismo , Humanos , Transdução de Sinais/fisiologia
12.
J Natl Cancer Inst ; 92(23): 1926-34, 2000 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-11106684

RESUMO

BACKGROUND: Most breast cancers, even those that are initially responsive to tamoxifen, ultimately become resistant. The molecular basis for this resistance, which in some patients is thought to involve stimulation of tumor growth by tamoxifen, is unclear. Tamoxifen induces cellular oxidative stress, and because changes in cell redox state can activate signaling pathways leading to the activation of activating protein-1 (AP-1), we investigated whether tamoxifen-resistant growth in vivo is associated with oxidative stress and/or activation of AP-1 in a xenograft model system where resistance is caused by tamoxifen-stimulated growth. METHODS: Control estrogen-treated, tamoxifen-sensitive, and tamoxifen-resistant MCF-7 xenograft tumors were assessed for oxidative stress by measuring levels of antioxidant enzyme (e.g., superoxide dismutase [SOD], glutathione S-transferase [GST], and hexose monophosphate shunt [HMS]) activity, glutathione, and lipid peroxidation. AP-1 protein levels, phosphorylated c-jun levels, and phosphorylated Jun NH(2)-terminal kinase (JNK) levels were examined by western blot analyses, and AP-1 DNA-binding and transcriptional activities were assessed by electrophoretic mobility shift assays and a reporter gene system. All statistical tests are two-sided. RESULTS: Compared with control estrogen-treated tumors, tamoxifen resistant tumors had statistically significantly increased SOD (more than threefold; P=.004) and GST (twofold; P=.004) activity and statistically significantly reduced glutathione levels (greater than twofold; P<.001) and HMS activity (10-fold; P<.001). Lipid peroxides were not significantly different between control and tamoxifen-resistant tumors. We observed no differences in AP-1 protein components or DNA-binding activity. However, AP-1-dependent transcription (P=.04) and phosphorylated c-Jun and JNK levels (P<.001) were statistically significantly increased in the tamoxifen-resistant tumors. CONCLUSION: Our results suggest that the conversion of breast tumors to a tamoxifen-resistant phenotype is associated with oxidative stress and the subsequent antioxidant response and with increased phosphorylated JNK and c-Jun levels and AP-1 activity, which together could contribute to tumor growth.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Moduladores de Receptor Estrogênico/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estresse Oxidativo , Tamoxifeno/farmacologia , Fator de Transcrição AP-1/metabolismo , Animais , Antineoplásicos Hormonais/uso terapêutico , Western Blotting , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Cloranfenicol O-Acetiltransferase/análise , DNA de Neoplasias/efeitos dos fármacos , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos , Moduladores de Receptor Estrogênico/uso terapêutico , Feminino , Glutationa Transferase/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno , Peroxidação de Lipídeos , Camundongos , Camundongos Nus , Via de Pentose Fosfato , Fenótipo , Fosforilação , Proteínas Proto-Oncogênicas c-jun/metabolismo , Superóxido Dismutase/metabolismo , Tamoxifeno/uso terapêutico , Transcrição Gênica/efeitos dos fármacos , Transplante Heterólogo
14.
Cancer Res ; 59(21): 5425-8, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10554010

RESUMO

It has been shown in previous studies that a variety of estrogen receptor (ER) beta mRNA transcripts are expressed in human breast cancer cell lines and tumors. To complement the RNA expression studies, we have developed ER-beta-specific antibodies to characterize ER-beta protein expression in breast cancer cell lines and tumors. Monoclonal antibodies were made against a peptide representing the first 18 amino acids of the longest ER-beta open reading frame reported to date, and polyclonal antibodies were made against a peptide within the ER-beta B domain. By Western blot analysis, we show that ER-beta protein is expressed in all cancer cell lines tested and in three of five breast tumor samples. The breast cancer cell lines showed variation in the size of the expressed ER-beta protein. The longest form detected was consistent with the 530-amino acid, full-length ER-beta sequence. Shorter ER-beta isoforms were detected in the ER-alpha-negative MDA-MB-231 and MDA-MB-435 breast cancer cell lines, likely corresponding to previously described COOH-terminal RNA variant isoforms.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Western Blotting , DNA Complementar/análise , Receptor beta de Estrogênio , Regulação Neoplásica da Expressão Gênica , Humanos , Osteossarcoma/metabolismo , Fenótipo , Isoformas de Proteínas , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas
15.
J Natl Cancer Inst ; 91(5): 453-9, 1999 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-10070945

RESUMO

BACKGROUND: Although the emerging complementary DNA (cDNA) array technology holds great promise to discern complex patterns of gene expression, its novelty means that there are no well-established standards to guide analysis and interpretation of the data that it produces. We have used preliminary data generated with the CLONTECH Atlas human cDNA array to develop a practical approach to the statistical analysis of these data by studying changes in gene expression during the development of acquired tamoxifen resistance in breast cancer. METHODS: For hybridization to the array, we prepared RNA from MCF-7 human breast cell tumors, isolated from our athymic nude mouse xenograft model of acquired tamoxifen resistance during estrogen-stimulated, tamoxifen-sensitive, and tamoxifen-resistant growth. Principal components analysis was used to identify genes with altered expression. RESULTS AND CONCLUSIONS: Principal components analysis yielded three principal components that are interpreted as 1) the average level of gene expression, 2) the difference between estrogen-stimulated gene expression and the average of tamoxifen-sensitive and tamoxifen-resistant gene expression, and 3) the difference between tamoxifen-sensitive and tamoxifen-resistant gene expression. A bivariate (second and third principal components) 99% prediction region was used to identify outlier genes that exhibit altered expression. Two representative outlier genes, erk-2 and HSF-1 (heat shock transcription factor-1), were chosen for confirmatory study, and their predicted relative expression levels were confirmed in western blot analysis, suggesting that semiquantitative estimates are possible with array technology. IMPLICATIONS: Principal components analysis provides a useful and practical method to analyze gene expression data from a cDNA array. The method can identify broad patterns of expression alteration and, based on a small simulation study, will likely provide reasonable power to detect moderate-sized alterations in clinically relevant genes.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Antagonistas de Estrogênios/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Tamoxifeno/farmacologia , Animais , Western Blotting , DNA Complementar/análise , DNA de Neoplasias/análise , Feminino , Humanos , Camundongos , Camundongos Nus , Técnicas de Sonda Molecular , Hibridização de Ácido Nucleico , Projetos Piloto , Células Tumorais Cultivadas
16.
N Engl J Med ; 340(7): 508-16, 1999 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-10021471

RESUMO

BACKGROUND: Since 1968 it has been known that bone marrow transplantation can ameliorate severe combined immunodeficiency, but data on the long-term efficacy of this treatment are limited. We prospectively studied immunologic function in 89 consecutive infants with severe combined immunodeficiency who received hematopoietic stem-cell transplants at Duke University Medical Center between May 1982 and September 1998. METHODS: Serum immunoglobulin levels and lymphocyte phenotypes and function were assessed and genetic analyses performed according to standard methods. Bone marrow was depleted of T cells by agglutination with soybean lectin and by sheep-erythrocyte rosetting before transplantation. RESULTS: Seventy-seven of the infants received T-cell-depleted, HLA-haploidentical parental marrow, and 12 received HLA-identical marrow from a related donor; 3 of the recipients of haploidentical marrow also received placental-blood transplants from unrelated donors. Except for two patients who received placental blood, none of the recipients received chemotherapy before transplantation or prophylaxis against graft-versus-host disease. Of the 89 infants, 72 (81 percent) were still alive 3 months to 16.5 years after transplantation, including all of the 12 who received HLA-identical marrow, 60 of the 77 (78 percent) who were given haploidentical marrow, and 2 of the 3 (67 percent) who received both haploidentical marrow and placental blood. T-cell function became normal within two weeks after transplantation in the patients who received unfractionated HLA-identical marrow but usually not until three to four months after transplantation in those who received T-cell-depleted marrow. At the time of the most recent evaluation, all but 4 of the 72 survivors had normal T-cell function, and all the T cells in their blood were of donor origin. B-cell function remained abnormal in many of the recipients of haploidentical marrow. In 26 children (5 recipients of HLA-identical marrow and 21 recipients of haploidentical marrow) between 2 percent and 100 percent of B cells were of donor origin. Forty-five of the 72 children were receiving intravenous immune globulin. CONCLUSIONS: Transplantation of marrow from a related donor is a life-saving and life-sustaining treatment for patients with any type of severe combined immunodeficiency, even when there is no HLA-identical donor.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Imunodeficiência Combinada Severa/terapia , Linfócitos B/fisiologia , Feminino , Doença Enxerto-Hospedeiro , Teste de Histocompatibilidade , Humanos , Lactente , Recém-Nascido , Células Matadoras Naturais/fisiologia , Depleção Linfocítica , Masculino , Fenótipo , Estudos Prospectivos , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/imunologia , Análise de Sobrevida , Linfócitos T/imunologia , Linfócitos T/fisiologia
17.
J Neurocytol ; 28(4-5): 397-416, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10739579

RESUMO

O1 hybridoma cells, which secrete an IgM antigalactocerebroside, were implanted into the spinal cord of cyclosporine-treated juvenile or adult rats, and the animals were sacrificed approximately 2-3 wk later. About half the recipient animals developed myelin lesions. In some, sharply circumscribed foci of demyelination formed within the dorsal columns. Cellular reaction consisted of macrophages containing refractile globules in the parenchyma and within enlarged perivascular spaces as well as thickened endothelial cells. "Shadow plaques" also developed, i.e. regions in which axons were surrounded by thin myelin sheaths, compatible with remyelination. In addition, we found damaged axons, some of which were swollen with organelles, comparable to the enlarged axon profiles seen at sites of constriction or interruption. Compromise of the blood-brain barrier at sites of hybridoma growth was demonstrated by extravasation of Evans blue dye. Discontinuation of cyclosporine was followed by an anti-hybridoma, complement-fixing antibody response within 2-3 d. This model of focal CNS demyelination and remyelination, with evidence of some axon damage, is mediated by a defined IgM antiglycolipid monoclonal antibody secreted within the spinal cord parenchyma. The lesions, which are similar to those of multiple sclerosis, probably result from the interaction between the intrathecally secreted IgM antibody and complement entering from the circulation at foci of compromised blood-brain barrier plus activation of endogenous or hematogenous macrophages via their complement receptors.


Assuntos
Doenças Desmielinizantes/imunologia , Galactosilceramidas/imunologia , Hibridomas/transplante , Imunoglobulina M/imunologia , Medula Espinal/imunologia , Medula Espinal/patologia , Fatores Etários , Animais , Barreira Hematoencefálica/imunologia , Transplante de Células , Células Cultivadas , Corantes/farmacocinética , Proteínas do Sistema Complemento/imunologia , Doenças Desmielinizantes/patologia , Azul Evans/farmacocinética , Hibridomas/metabolismo , Imunoglobulina G/imunologia , Imunoglobulina M/metabolismo , Macrófagos/imunologia , Masculino , Microscopia Eletrônica , Bainha de Mielina/imunologia , Bainha de Mielina/patologia , Bainha de Mielina/ultraestrutura , Ratos , Ratos Wistar , Medula Espinal/irrigação sanguínea
18.
Ann Intern Med ; 128(8): 693; author reply 694, 1998 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9537946
19.
Proc Natl Acad Sci U S A ; 95(6): 2920-5, 1998 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-9501191

RESUMO

Several lines of evidence indicate that the nuclear receptor corepressor (N-CoR) complex imposes ligand dependence on transcriptional activation by the retinoic acid receptor and mediates the inhibitory effects of estrogen receptor antagonists, such as tamoxifen, suppressing a constitutive N-terminal, Creb-binding protein/coactivator complex-dependent activation domain. Functional interactions between specific receptors and N-CoR or SMRT corepressor complexes are regulated, positively or negatively, by diverse signal transduction pathways. Decreased levels of N-CoR correlate with the acquisition of tamoxifen resistance in a mouse model system for human breast cancer. Our data suggest that N-CoR- and SMRT-containing complexes act as rate-limiting components in the actions of specific nuclear receptors, and that their actions are regulated by multiple signal transduction pathways.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Antagonistas de Estrogênios/farmacologia , Proteínas Nucleares/metabolismo , Receptores de Estrogênio/metabolismo , Proteínas Repressoras/metabolismo , Tamoxifeno/farmacologia , Animais , Neoplasias da Mama/metabolismo , Modelos Animais de Doenças , Resistência a Medicamentos , Regulação da Expressão Gênica , Genes Reporter , Humanos , Camundongos , Modelos Biológicos , Correpressor 1 de Receptor Nuclear , Correpressor 2 de Receptor Nuclear , Ligação Proteica , Proteínas Quinases/metabolismo , Receptores do Ácido Retinoico/metabolismo , Transdução de Sinais
20.
J Pediatr ; 132(1): 15-21, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9469994

RESUMO

OBJECTIVE: DiGeorge syndrome is characterized by developmental defects of the heart, parathyroid glands, and thymus. The objective of this study was to determine whether T-cell function spontaneously improves in patients with DiGeorge syndrome who have profoundly depressed T-cell proliferative responses to mitogens at presentation, regardless of the T-cell count. STUDY DESIGN: We conducted a retrospective chart review of eight patients with DiGeorge syndrome who had no proliferative responses to mitogens on presentation. RESULTS: Despite lack of responsiveness of the patients' peripheral blood lymphocytes to mitogens, T cells were occasionally detected, and the patients' cells often responded to IL-2 and in mixed lymphocyte reactions. Unresponsiveness to mitogens and clinical immunodeficiency persisted without immune-based therapy. One patient is alive and well after immunoreconstitution from thymic transplantation. The others either died early of complications of their disease such as gastroesophageal reflux with aspiration (2 patients) or infection (2 patients) or died after attempts at immunorestorative therapy with IL-2, thymus transplantation, or bone marrow transplantation (3 patients). CONCLUSION: Eight patients with DiGeorge syndrome who were first seen with no mitogen responsiveness did not improve spontaneously. We recommend HLA-identical bone marrow transplantation or thymic transplantation for these patients as soon as the diagnosis is confirmed.


Assuntos
Síndrome de DiGeorge/imunologia , Ativação Linfocitária , Linfócitos T/imunologia , Transplante de Medula Óssea , Complexo CD3 , Antígenos CD4 , Antígenos CD8 , Pré-Escolar , Síndrome de DiGeorge/diagnóstico , Síndrome de DiGeorge/terapia , Evolução Fatal , Citometria de Fluxo , Doença Enxerto-Hospedeiro , Humanos , Imunoglobulinas/sangue , Lactente , Interleucina-2/uso terapêutico , Contagem de Linfócitos , Estudos Retrospectivos , Timo/transplante
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...