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1.
Cell Death Differ ; 15(11): 1752-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18617895

RESUMO

Yes-associated protein (YAP) has been shown to positively regulate p53 family members and to be negatively regulated by the AKT proto-oncogene product in promoting apoptosis. On the basis of this function and its location at 11q22.2, a site of frequent loss of heterozygosity (LOH) in breast cancer, we investigated whether YAP is a tumor suppressor in breast. Examination of tumors by immunohistochemistry demonstrated significant loss of YAP protein. LOH analysis revealed that protein loss correlates with specific deletion of the YAP gene locus. Functionally, short hairpin RNA knockdown of YAP in breast cell lines suppressed anoikis, increased migration and invasiveness, inhibited the response to taxol and enhanced tumor growth in nude mice. This is the first report indicating YAP as a tumor suppressor, revealing its decreased expression in breast cancer as well as demonstrating the functional implications of YAP loss in several aspects of cancer signaling.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Mama/metabolismo , Fosfoproteínas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Anoikis/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Resistência a Medicamentos/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Deleção de Genes , Inativação Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica , Paclitaxel/farmacologia , Fosfoproteínas/genética , Proto-Oncogene Mas , Fatores de Transcrição , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas de Sinalização YAP
2.
Cell Death Dis ; 1: e29, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21364637

RESUMO

Yes-associated protein (YAP) regulates DNA damage and chemosensitivity, as well as functioning as a pro-growth, cell size regulator. For both of its roles, regulation by phosphorylation is crucial. We undertook an in vitro screen to identify novel YAP kinases to discover new signaling pathways to better understand YAP's function. We identified JNK1 and JNK2 as robust YAP kinases, as well as mapped multiple sites of phosphorylation. Using inhibitors and siRNA, we showed that JNK specifically phosphorylates endogenous YAP in a number of cell types. We show that YAP protects keratinocytes from UV irradiation but promotes UV-induced apoptosis in a squamous cell carcinoma. We defined the mechanism for this dual role to be YAP's ability to bind and stabilize the pro-proliferative ΔNp63α isoform in a JNK-dependent manner. Our report indicates that an evaluation of the expression of the different isoforms of p63 and p73 is crucial in determining YAP's function.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , Fosfoproteínas/metabolismo , Apoptose/efeitos da radiação , Linhagem Celular , Humanos , Fosforilação/efeitos da radiação , Ligação Proteica/efeitos da radiação , Estabilidade Proteica/efeitos da radiação , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Raios Ultravioleta , Proteínas de Sinalização YAP
3.
BMJ ; 340: c2102, 2010 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-20460331

RESUMO

OBJECTIVE: To evaluate whether a service to prevent falls in the community would help reduce the rate of falls in older people who call an emergency ambulance when they fall but are not taken to hospital. DESIGN: Randomised controlled trial. SETTING: Community covered by four primary care trusts, England. PARTICIPANTS: 204 adults aged more than 60 living at home or in residential care who had fallen and called an emergency ambulance but were not taken to hospital. INTERVENTIONS: Referral to community fall prevention services or standard medical and social care. MAIN OUTCOME MEASURES: The primary outcome was the rate of falls over 12 months, ascertained from monthly diaries. Secondary outcomes were scores on the Barthel index, Nottingham extended activities of daily living scale, and falls efficacy scale at baseline and by postal questionnaire at 12 months. Analysis was by intention to treat. RESULTS: 102 people were allocated to each group. 99 (97%) participants in the intervention group received the intervention. Falls diaries were analysed for 88.6 person years in the intervention group and 84.5 person years in the control group. The incidence rates of falls per year were 3.46 in the intervention group and 7.68 in the control group (incidence rate ratio 0.45, 95% confidence interval 0.35 to 0.58, P<0.001). The intervention group achieved higher scores on the Barthel index and Nottingham extended activities of daily living and lower scores on the falls efficacy scale (all P<0.05) at the 12 month follow-up. The number of times an emergency ambulance was called because of a fall was significantly different during follow-up (incidence rate ratio 0.60, 95% confidence interval 0.40 to 0.92, P=0.018). CONCLUSION: A service to prevent falls in the community reduced the fall rate and improved clinical outcome in the high risk group of older people who call an emergency ambulance after a fall but are not taken to hospital. TRIAL REGISTRATION: Current Controlled Trials ISRCTN67535605.


Assuntos
Acidentes por Quedas/prevenção & controle , Ambulâncias/estatística & dados numéricos , Serviços de Saúde Comunitária/organização & administração , Acidentes por Quedas/estatística & dados numéricos , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Emergências , Inglaterra , Terapia por Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Equipe de Assistência ao Paciente , Equilíbrio Postural , Encaminhamento e Consulta , Medição de Risco , Resultado do Tratamento
4.
Mo Med ; 89(5): 269, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1608385
6.
J Biol Chem ; 282(39): 28951-28959, 2007 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17640869

RESUMO

Translation elongation factor eEF1A, formerly known as EF-1 alpha, exists as two variant forms; eEF1A1, which is almost ubiquitously expressed, and eEF1A2, whose expression is restricted to muscle and brain at the level of whole tissues. Expression analysis of these genes has been complicated by a general lack of availability of antibodies that specifically recognize each variant form. Wasted mice (wst/wst) have a 15.8-kilobase deletion that abolishes activity of eEF1A2, but before this study it was unknown whether the deletion also affected neighboring genes. We have generated a panel of anti-peptide antibodies and used them to show that eEF1A2 is expressed at high levels in specific cell types in tissues previously thought not to express this variant, such as pancreatic islet cells and enteroendocrine cells in colon crypts. Expression of eEF1A1 and eEF1A2 is shown to be generally mutually exclusive, and we relate the expression pattern of eEF1A2 to the phenotype seen in wasted mice. We then carried out a series of transgenic experiments to establish whether the expression of other genes is affected by the deletion in wasted mice. We show that aspects of the phenotype such as motor neuron degeneration relate precisely to the relative expression of eEF1A1 and eEF1A2, whereas the immune system abnormalities are likely to result from a stress response. We conclude that loss of eEF1A2 function is solely responsible for the abnormalities seen in these mice.


Assuntos
Regulação da Expressão Gênica , Sistema Imunitário/metabolismo , Fator 1 de Elongação de Peptídeos/biossíntese , Síndrome de Emaciação/metabolismo , Animais , Sequência de Bases/genética , Colo/imunologia , Colo/metabolismo , Colo/patologia , Regulação da Expressão Gênica/imunologia , Humanos , Sistema Imunitário/anormalidades , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Camundongos , Camundongos Mutantes , Camundongos Transgênicos , Doença dos Neurônios Motores/genética , Doença dos Neurônios Motores/imunologia , Doença dos Neurônios Motores/metabolismo , Doença dos Neurônios Motores/patologia , Especificidade de Órgãos/genética , Especificidade de Órgãos/imunologia , Fator 1 de Elongação de Peptídeos/genética , Fator 1 de Elongação de Peptídeos/imunologia , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Deleção de Sequência , Síndrome de Emaciação/genética , Síndrome de Emaciação/imunologia , Síndrome de Emaciação/patologia , Desmame
7.
Br J Cancer ; 96(10): 1613-20, 2007 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-17437010

RESUMO

The tissue-specific translation elongation factor eEF1A2 is a potential oncogene that is overexpressed in human ovarian cancer. eEF1A2 is highly similar (98%) to the near-ubiquitously expressed eEF1A1 (formerly known as EF1-alpha) making analysis with commercial antibodies difficult. We wanted to establish the expression pattern of eEF1A2 in ovarian cancer of defined histological subtypes at both the RNA and protein level, and to establish the mechanism for the overexpression of eEF1A2 in tumours. We show that while overexpression of eEF1A2 is seen at both the RNA and protein level in up to 75% of clear cell carcinomas, it occurs at a lower frequency in other histological subtypes. The copy number at the EEF1A2 locus does not correlate with expression level of the gene, no functional mutations were found, and the gene is unmethylated in both normal and tumour DNA, showing that overexpression is not dependent on genetic or epigenetic modifications at the EEF1A2 locus. We suggest that the cause of overexpression of eEF1A2 may be the inappropriate expression of a trans-acting factor. The oncogenicity of eEF1A2 may be related either to its role in protein synthesis or to potential non-canonical functions.


Assuntos
Adenocarcinoma de Células Claras/genética , Epigênese Genética/fisiologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/genética , Fator 1 de Elongação de Peptídeos/genética , Adenocarcinoma de Células Claras/patologia , Metilação de DNA , Feminino , Perfilação da Expressão Gênica , Células HL-60 , Células HeLa , Humanos , Neoplasias Ovarianas/patologia , Células Tumorais Cultivadas
8.
Br Med J (Clin Res Ed) ; 283(6301): 1209-11, 1981 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-6797512

RESUMO

The cytotoxic effect of cigarette smoke condensate on human polymorphs was investigated in vitro by the method of vital dye exclusion. Exposure to 1/800 of the smoke from one high-tar cigarette killed a detectable proportion of a population of 10(6) cells. The response among the cells from 40 healthy people varied widely, the percentage of dead cells ranging from 3% to 66% and from 17% to 87% at exposure levels of 125 micrograms and 250 micrograms cigarette smoke condensate respectively. Differences in individuals' responses were reproducible and unrelated to age or sex or smoking habit. The cells from 10 patients with irreversible obstructive airways disease and probable emphysema were significantly more sensitive than those from 10 patients with no respiratory disability matched for age and smoking habits. Genetically influenced variation in cellular response to cytotoxicity may be an important determinant of the risk of developing emphysema among smokers.


Assuntos
Neutrófilos , Nicotiana , Plantas Tóxicas , Fumaça , Adulto , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Enfisema Pulmonar/etiologia , Risco
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