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1.
Rev Med Liege ; 79(5-6): 448-454, 2024 Jun.
Artigo em Francês | MEDLINE | ID: mdl-38869138

RESUMO

Preeclampsia is a pregnancy-specific condition characterized by gestational hypertension associated with proteinuria or organ dysfunction after 20 weeks of gestation. It complicates 2 to 8 % of pregnancies worldwide and represents the leading cause of maternal and fetal mortality in developed countries. The only definitive treatment remains termination of pregnancy and delivery of the placenta. Prompt assessment of maternal and fetal status should be held in search of severity criteria and adequate management of this condition according to gestational age. Foremost concerns for pregnant patients are impending eclampsia or placental abruption, while fetal complications arise from placental insufficiency and risks associated with premature pregnancy termination. The sole efficient prophylaxis of preeclampsia in current state of evidence is aspirin at a dosage of 160 mg per day in high risk patients. Preeclampsia is now recognized as a high-risk factor for cardiovascular, renal, and neurological diseases and should therefore be considered as an opportunity for screening and prevention.


La prééclampsie (PE) est un syndrome unique à la grossesse défini par une hypertension artérielle gravidique, associée à une protéinurie ou une atteinte d'organe après 20 semaines d'aménorrhée. Elle complique 2 à 8 % des grossesses à l'échelle mondiale, et représente la première cause de mortalité maternelle et fœtale dans les pays industrialisés. Le seul traitement curatif demeure l'arrêt de la grossesse et la délivrance du placenta. Cette pathologie justifie une évaluation rapide de l'état maternel et fœtal, afin de juger des critères de sévérité et d'orienter la prise en charge selon le terme de la grossesse. La menace maternelle est dominée par le risque de survenue d'une éclampsie ou d'un hématome rétroplacentaire alors que les complications fœtales découlent de l'insuffisance placentaire et des risques inhérents à un arrêt prématuré de grossesse. Le seul traitement préventif actuellement validé en prévention secondaire chez les patientes à haut risque est l'aspirine à une dose de 160 mg par jour. La PE est désormais reconnue comme un facteur de risque cardiovasculaire, rénal et neurologique, et doit être considérée, de ce fait, comme une opportunité de dépistage et de prévention.


Assuntos
Pré-Eclâmpsia , Humanos , Gravidez , Pré-Eclâmpsia/prevenção & controle , Pré-Eclâmpsia/diagnóstico , Feminino , Fatores de Risco
2.
Rev Med Liege ; 79(5-6): 442-447, 2024 Jun.
Artigo em Francês | MEDLINE | ID: mdl-38869137

RESUMO

Follow-up consultations in gynaecology and general practice offer valuable opportunities to discuss fertility and the importance of a pre-conceptional assessment before attempting pregnancy. During these consultations, it is vital for healthcare professionals to provide patients with essential information about considerations before conceiving a child. Additionally, it is important to educate patients about basic hygiene practices that can impact both male and female fertility. The prevention of fertility disorders requires a holistic approach identifying and targeting numerous risk factors.


Les consultations de suivi en gynécologie et en médecine générale offrent des opportunités précieuses pour discuter de la fertilité et de l'importance d'une évaluation préconceptionnelle avant toute tentative de grossesse. Au cours de ces consultations, il est primordial pour les professionnels de santé de fournir aux patients des informations essentielles concernant les aspects à considérer avant de concevoir un enfant. De plus, il convient de sensibiliser les patients aux pratiques d'hygiène de base qui peuvent avoir un impact sur la fertilité masculine et féminine. La prévention des troubles de la fertilité nécessite une approche holistique identifiant et ciblant de nombreux facteurs de risque.


Assuntos
Infertilidade , Humanos , Fatores de Risco , Feminino , Masculino , Infertilidade/prevenção & controle , Gravidez , Infertilidade Feminina/prevenção & controle
3.
Epilepsy Res ; 198: 107260, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38007914

RESUMO

PURPOSE: Patients with severe drug-resistant epilepsy (DRE) experience psychomotor disorders. Our study aimed to assess the psychomotor outcomes after vagus nerve stimulation (VNS) in this population. METHODS: We prospectively evaluated psychomotor function in 17 adult patients with severe DRE who were referred for VNS. Psychomotor functions were examined, in the preoperative period and at 18 months post-surgery, by a psychomotor therapist using a full set of the following specific tests: the Rey-Osterrieth complex figure (ROCF) test, the Zazzo's cancelation task (ZCT), the Piaget-Head test and the paired images test. RESULTS: At 18 months post-VNS surgery, the Piaget-head scores increased by 3 points (p = 0.008) compared to baseline. Performances were also improved for ROCF test both in copy (+2.4 points, p = 0.001) and recall (+2.0 points, p = 0.008) tasks and for the paired images test (accuracy index: +28.6 %, p = 0.03). Regarding the ZCT findings, the efficiency index increased in both single (+16 %, p = 0.005) and dual (+17.1 %, p < 0.001) tasks. QoL improved in 88.2 % of patients. CONCLUSIONS: Patients with severe DRE treated with VNS experienced improved performance in terms of global psychomotor functions. Perceptual organization, visuospatial memory, laterality awareness, sustained attention, concentration, visual scanning, and inhibition were significantly improved.


Assuntos
Epilepsia Resistente a Medicamentos , Estimulação do Nervo Vago , Adulto , Humanos , Estimulação do Nervo Vago/métodos , Qualidade de Vida , Epilepsia Resistente a Medicamentos/terapia , Rememoração Mental , Desempenho Psicomotor , Resultado do Tratamento , Nervo Vago
4.
Epilepsy Behav ; 118: 107931, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33770612

RESUMO

PURPOSE: Vagus nerve stimulation (VNS) implantation is increasingly proposed in outpatient procedure. Some epilepsy syndromes are associated with severe neurodevelopmental disabilities (intellectual disability, autism) and often motor or sensory handicaps, making ambulatory surgery more complex. METHODS: We prospectively assessed the feasibility and safety of outpatient VNS implantation in 26 adult patients with drug-resistant epilepsy with severe intellectual disability between December 2017 and October 2020. RESULTS: The male-to-female ratio was 0.9 and the mean age on surgery day was 23.1 years. Seventeen patients (65.4%) suffered from epileptic encephalopathy, 7 (26.9%) from cryptogenic or genetic generalized epilepsy, and 2 (7.7%) from severe multifocal epilepsy. Postoperatively, all patients were discharged the day of surgery. No patient was admitted to a hospital or have consulted within one month due to postoperative complications. There was no surgery-related complication during patients' follow-up. CONCLUSION: Our study highlights the safety and feasibility of VNS surgery in an outpatient setting for patients with severe intellectual disability. We report detailed protocol and preoperative checklist to optimize outpatient VNS surgery in these not able-bodied patients. Severe disabilities or epilepsy-associated handicaps should not be an exclusion criterion when considering ambulatory VNS implantation.


Assuntos
Epilepsia , Deficiência Intelectual , Preparações Farmacêuticas , Estimulação do Nervo Vago , Adulto , Procedimentos Cirúrgicos Ambulatórios , Epilepsia/complicações , Epilepsia/terapia , Feminino , Humanos , Deficiência Intelectual/complicações , Masculino , Pacientes Ambulatoriais , Resultado do Tratamento , Nervo Vago
5.
Epilepsy Behav ; 81: 49-54, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29477011

RESUMO

OBJECTIVE: The objective of this study was to test the reliability of functional magnetic resonance imaging (fMRI) evaluation of memory function in clinical practice to predict postoperative memory decline in patients with refractory medial temporal lobe epilepsy (MTLE) candidate to surgery. METHODS: Twenty-six consecutive patients with MTLE who underwent a complete presurgical evaluation were included. All patients underwent fMRI memory study and complete neuropsychological assessment. Lesions consisted in hippocampal sclerosis in 18 patients (12 right and 6 left), dysembryoplastic neuroepithelial tumor (DNET) in 5 cases (4 right, 1 left), epidermoid cyst in one patient (right). Two patients had no lesion (2 left). RESULTS: Nineteen patients (73%) underwent surgery. The other seven patients (27%) declined surgery, mainly because of the risk of memory deficit. The fMRI procedure correctly predicted both verbal and nonverbal memory postoperative outcome in 13 of the patients (72%), failed to predict a postoperative memory worsening in only two patients (12%), and predicted worsening in three patients (17%) that remained stable (versus 44%, 39%, and 17% with the sole neuropsychological testing). The reliability of the fMRI procedure was not influenced by the type of lesion, the side of the epileptic focus, or the type of preoperative memory profile (typical or atypical). SIGNIFICANCE: Appearing as a valuable clinical tool to predict postoperative memory outcome, fMRI may add information over and above other available tests.


Assuntos
Epilepsia do Lobo Temporal/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Transtornos da Memória/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Adulto , Epilepsia do Lobo Temporal/patologia , Epilepsia do Lobo Temporal/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Memória/fisiologia , Transtornos da Memória/etiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Período Pós-Operatório , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
6.
Future Med Chem ; 9(13): 1465-1481, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28795598

RESUMO

AIM: DNA methyltransferases (DNMTs) are important drug targets for epigenetic therapy of cancer. Nowadays, non-nucleoside DNMT inhibitors are in development to address high toxicity of nucleoside analogs. However, these compounds still have low activity in cancer cells and mode of action of these compounds remains unclear. MATERIALS & METHODS: In this work, we studied maleimide derivatives of RG108 by biochemical, structural and computational approaches to highlight their inhibition mechanism on DNMTs. RESULTS: Findings demonstrated a correlation between cytotoxicity on mesothelioma cells of these compounds and their inhibitory potency against DNMTs. Noncovalent and covalent docking studies, supported by crystallographic (apo structure of M.HhaI) and differential scanning fluorimetry assays, provided detailed insights into their mode of action and revealed essential residues for the stabilization of such compounds inside DNMTs. [Formula: see text].


Assuntos
DNA (Citosina-5-)-Metiltransferases/metabolismo , Maleimidas/química , Ftalimidas/química , Triptofano/análogos & derivados , Animais , Apoenzimas/antagonistas & inibidores , Apoenzimas/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/toxicidade , Fluorometria , Humanos , Concentração Inibidora 50 , Camundongos , Simulação de Acoplamento Molecular , Ftalimidas/metabolismo , Ftalimidas/toxicidade , Estrutura Terciária de Proteína , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Triptofano/química , Triptofano/metabolismo , Triptofano/toxicidade
7.
J Med Chem ; 60(11): 4665-4679, 2017 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-28463515

RESUMO

Aberrant DNA hypermethylation of promoter of tumor suppressor genes is commonly observed in cancer, and its inhibition by small molecules is promising for their reactivation. Here we designed bisubstrate analogues-based inhibitors, by mimicking each substrate, the S-adenosyl-l-methionine and the deoxycytidine, and linking them together. This approach resulted in quinazoline-quinoline derivatives as potent inhibitors of DNMT3A and DNMT1, some showing certain isoform selectivity. We highlighted the importance of (i) the nature and rigidity of the linker between the two moieties for inhibition, as (ii) the presence of the nitrogen on the quinoline group, and (iii) of a hydrophobic group on the quinazoline. The most potent inhibitors induced demethylation of CDKN2A promoter in colon carcinoma HCT116 cells and its reactivation after 7 days of treatment. Furthermore, in a leukemia cell model system, we found a correlation between demethylation of the promoter induced by the treatment, chromatin opening at the promoter, and the reactivation of a reporter gene.


Assuntos
DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , Desenho de Fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Neoplasias/enzimologia , Linhagem Celular Tumoral , DNA (Citosina-5-)-Metiltransferase 1 , Metilação de DNA , DNA Metiltransferase 3A , Genes Supressores de Tumor , Humanos , Neoplasias/patologia , Especificidade por Substrato
8.
BMC Cancer ; 16: 700, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27581651

RESUMO

BACKGROUND: In breast cancer, the epithelial to mesenchyme transition (EMT) is associated to tumour dissemination, drug resistance and high relapse risks. It is partly controlled by epigenetic modifications such as histone acetylation and methylation. The identification of genes involved in these reversible modifications represents an interesting therapeutic strategy to fight metastatic disease by inducing mesenchymal cell differentiation to an epithelial phenotype. METHODS: We designed a siRNA library based on chromatin modification-related to functional domains and screened it in the mesenchymal breast cancer cell line MDA-MB-231. The mesenchyme to epithelium transition (MET) activation was studied by following human E-CADHERIN (E-CAD) induction, a specific MET marker, and cell morphology. Candidate genes were validated by studying the expression of several differential marker genes and their impact on cell migration. RESULTS: The screen led to the identification of 70 gene candidates among which some are described to be, directly or indirectly, involved in EMT like ZEB1, G9a, SMAD5 and SMARCD3. We also identified the DOT1L as involved in EMT regulation in MDA-MB-231. Moreover, for the first time, KAT5 gene was linked to the maintenance of the mesenchymal phenotype. CONCLUSIONS: A multi-parametric RNAi screening approach was developed to identify new EMT regulators such as KAT5 in the triple negative breast cancer cell line MDA-MB-231.


Assuntos
Neoplasias da Mama/patologia , Transição Epitelial-Mesenquimal/genética , Interferência de RNA , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Feminino , Técnicas de Silenciamento de Genes , Humanos , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real
9.
Future Med Chem ; 8(4): 373-80, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26976348

RESUMO

DNA methylation is the most studied epigenetic event. Since the methylation profile of the genome is widely modified in cancer cells, DNA methyltransferases are the target of new anticancer therapies. Nucleosidic inhibitors suffer from toxicity and chemical stability, while non-nucleosidic inhibitors lack potency. Here, we found a novel DNMT inhibitor scaffold by enzymatic screening and structure-activity relationship studies. The optimization studies led to an inhibitor containing three fragments: a gallate frame, a hydrazone linker and a benzothiazole moiety. Interestingly, the compound inhibits DNMT3A with micromolar potency (EC50 = 1.6 µM) and does not inhibit DNMT1; this DNMT3A selectivity is supported by a docking study. Finally, the compound reactivates a reporter gene in leukemia KG-1 cells.


Assuntos
Antineoplásicos/farmacologia , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Ácido Gálico/farmacologia , Hidrazonas/farmacologia , Neoplasias/tratamento farmacológico , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Ácido Gálico/química , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Neoplasias/metabolismo , Relação Estrutura-Atividade
10.
PLoS One ; 9(5): e96941, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24810902

RESUMO

Chemical manipulations performed on the histone H3 lysine 9 methyltransferases (G9a/GLP) inhibitor BIX-01294 afforded novel desmethoxyquinazolines able to inhibit the DNA methyltransferase DNMT3A at low micromolar levels without any significant inhibition of DNMT1 and G9a. In KG-1 cells such compounds, when tested at sub-toxic doses, induced the luciferase re-expression in a stable construct controlled by a cytomegalovirus (CMV) promoter silenced by methylation (CMV-luc assay). Finally, in human lymphoma U-937 and RAJI cells, the N-(1-benzylpiperidin-4-yl)-2-(4-phenylpiperazin-1-yl)quinazolin-4-amine induced the highest proliferation arrest and cell death induction starting from 10 µM, in agreement with its DNMT3A inhibitory potency.


Assuntos
Azepinas/química , Azepinas/farmacologia , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Quinazolinas/química , Quinazolinas/farmacologia , Azepinas/metabolismo , Domínio Catalítico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferases/química , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Inibidores Enzimáticos/metabolismo , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Simulação de Acoplamento Molecular , Quinazolinas/metabolismo , Relação Estrutura-Atividade
11.
ChemMedChem ; 9(3): 590-601, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24678024

RESUMO

Quinoline derivative SGI-1027 (N-(4-(2-amino-6-methylpyrimidin-4-ylamino)phenyl)-4-(quinolin-4-ylamino)benzamide) was first described in 2009 as a potent inhibitor of DNA methyltransferase (DNMT) 1, 3A and 3B. Based on molecular modeling studies, performed using the crystal structure of Haemophilus haemolyticus cytosine-5 DNA methyltransferase (MHhaI C5 DNMT), which suggested that the quinoline and the aminopyridimine moieties of SGI-1027 are important for interaction with the substrates and protein, we designed and synthesized 25 derivatives. Among them, four compounds­namely the derivatives 12, 16, 31 and 32­exhibited activities comparable to that of the parent compound. Further evaluation revealed that these compounds were more potent against human DNMT3A than against human DNMT1 and induced the re-expression of a reporter gene, controlled by a methylated cytomegalovirus (CMV) promoter, in leukemia KG-1 cells. These compounds possessed cytotoxicity against leukemia KG-1 cells in the micromolar range, comparable with the cytotoxicity of the reference compound, SGI-1027. Structure­activity relationships were elucidated from the results. First, the presence of a methylene or carbonyl group to conjugate the quinoline moiety decreased the activity. Second, the size and nature of the aromatic or heterocycle subsitutents effects inhibition activity: tricyclic moieties, such as acridine, were found to decrease activity, while bicyclic substituents, such as quinoline, were well tolerated. The best combination was found to be a bicyclic substituent on one side of the compound, and a one-ring moiety on the other side. Finally, the orientation of the central amide bond was found to have little effect on the biological activity. This study provides new insights in to the structure-activity relationships of SGI-1027 and its derivative.


Assuntos
Aminoquinolinas/síntese química , Aminoquinolinas/farmacologia , Metilação de DNA/efeitos dos fármacos , Desenho de Fármacos , Pirimidinas/síntese química , Pirimidinas/farmacologia , Quinolinas/química , Aminoquinolinas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Pirimidinas/química , Relação Estrutura-Atividade
12.
Presse Med ; 40(3): 293-300, 2011 Mar.
Artigo em Francês | MEDLINE | ID: mdl-21310584

RESUMO

Epilepsy surgery concerns any patient with pharmacoresistant partial epilepsy, responsible for disability. Children and adult patients can be candidates for epilepsy surgery. A presurgical evaluation, adapted to each patient, must identify the most precisely the cortical area, where the seizures originate, using converging data: the clinical and electroencephalographic semiology of the seizures, the structural and sometimes functional brain imagings, and evaluate if the removal of the epileptogenic focus may induce a neurological or cognitive deficit, using neuropsychological tests and sometimes functional brain imagings. Such therapeutical strategy should be evoked as soon as possible in patients for whom the epilepsy becomes pharmacoresistant, and these patients should be oriented in specialized centres. The results of epilepsy surgery vary according to the lobar origin of the epileptogenic focus and to the existence of a visible lesion on brain MRI. A multidisciplinary evaluation of the benefits and risks should be presented to the patient. Results of the surgery are usually excellent when a focus is clearly identified and the neuropsychological tests did not predict a deficit.


Assuntos
Encéfalo/cirurgia , Epilepsia/etiologia , Epilepsia/cirurgia , Adulto , Anticonvulsivantes/uso terapêutico , Encéfalo/fisiopatologia , Mapeamento Encefálico , Córtex Cerebral/fisiopatologia , Córtex Cerebral/cirurgia , Criança , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/prevenção & controle , Resistência a Medicamentos , Eletroencefalografia , Epilepsia/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Encaminhamento e Consulta , Fatores de Risco , Processamento de Sinais Assistido por Computador
13.
Cancer Res ; 67(7): 3371-8, 2007 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-17409447

RESUMO

Microtubules are centrally involved in cell division, being the principal components of mitotic spindle. Tubulin, the constituent of microtubules, can be cyclically modified on its alpha-subunit by enzymatic removal of the COOH-terminal tyrosine residue by an ill-defined tubulin carboxypeptidase (TCP) and its readdition by tubulin tyrosine ligase (TTL). We and others have previously shown that suppression of TTL and resulting accumulation of detyrosinated tubulin are frequent in human cancers of poor prognosis. Explanations for the involvement of TTL and detyrosinated tubulin in tumor progression arise from the recent discovery that tubulin detyrosination leads to CAP-Gly protein mislocalization, which correlates with defects in spindle positioning during mitosis. Impaired control of spindle positioning is one factor favoring tumor invasiveness. Thus, TCP could be a target for developing novel therapeutic strategies against advanced stages of cancers. Inhibitors of TCP, by reversing abnormal detyrosinated tubulin accumulation in tumor cells, could impair tumor progression. TCP has never been isolated and this has hampered search of specific inhibitors. In this article, we describe a cell-based assay of TCP activity and its use to screen a library of natural extracts for their inhibitory potency. This led to the isolation of two sesquiterpene lactones. We subsequently found that parthenolide, a structurally related compound, can efficiently inhibit TCP. This inhibitory activity is a new specific property of parthenolide independent of its action on the nuclear factor-kappaB pathway. Parthenolide is also known for its anticancer properties. Thus, TCP inhibition could be one of the underlying mechanisms of these anticancer properties.


Assuntos
Carboxipeptidases/antagonistas & inibidores , Sesquiterpenos/farmacologia , Carboxipeptidases/metabolismo , Interações Medicamentosas , Células HeLa , Humanos , NF-kappa B/antagonistas & inibidores , Paclitaxel/farmacologia , Sesquiterpenos/química , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo
14.
FASEB J ; 19(2): 234-6, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15550552

RESUMO

The matrix metalloproteinases (MMPs) play a key role in normal and pathological angiogenesis by mediating extracellular matrix degradation and/or controlling the biological activity of growth factors, chemokines, and/or cytokines. Specific functions of individual MMPs as anti- or proangiogenic mediators remain to be elucidated. In the present study, we assessed the impact of single or combined MMP deficiencies in in vivo and in vitro models of angiogenesis (malignant keratinocyte transplantation and the aortic ring assay, respectively). MMP-9 was predominantly expressed by neutrophils in tumor transplants, whereas MMP-2 and MMP-3 were stromal. Neither the single deficiency of MMP-2, MMP-3, or MMP-9, nor the combined absence of MMP-9 and MMP-3 did impair tumor invasion and vascularization in vivo. However, there was a striking cooperative effect in double MMP-2:MMP-9-deficient mice as demonstrated by the absence of tumor vascularization and invasion. In contrast, the combined lack of MMP-2 and MMP-9 did not impair the in vitro capillary outgrowth from aortic rings. These results point to the importance of a cross talk between several host cells for the in vivo tumor promoting and angiogenic effects of MMP-2 and MMP-9. Our data demonstrate for the first time in an experimental model that MMP-2 and MMP-9 cooperate in promoting the in vivo invasive and angiogenic phenotype of malignant keratinocytes.


Assuntos
Queratinócitos/patologia , Metaloproteinase 2 da Matriz/fisiologia , Metaloproteinase 9 da Matriz/fisiologia , Neoplasias/irrigação sanguínea , Neoplasias/enzimologia , Neovascularização Patológica/enzimologia , Animais , Linhagem Celular Tumoral , Queratinócitos/química , Queratinócitos/metabolismo , Metaloproteinase 2 da Matriz/deficiência , Metaloproteinase 3 da Matriz/deficiência , Metaloproteinase 3 da Matriz/fisiologia , Metaloproteinase 9 da Matriz/deficiência , Metaloproteinase 9 da Matriz/genética , Camundongos , Camundongos Endogâmicos , Camundongos Mutantes , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Transplante de Neoplasias/métodos , Transplante de Neoplasias/patologia , Neoplasias/genética , Neoplasias/patologia , Regiões Promotoras Genéticas/genética
15.
FASEB J ; 16(2): 147-54, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11818362

RESUMO

Plasminogen activator inhibitor 1 (PAI-1) is believed to control proteolytic activity and cell migration during angiogenesis. We previously demonstrated in vivo that this inhibitor is necessary for optimal tumor invasion and vascularization. We also showed that PAI-1 angiogenic activity is associated with its control of plasminogen activation but not with the regulation of cell-matrix interaction. To dissect the role of the various components of the plasminogen activation system during angiogenesis, we have adapted the aortic ring assay to use vessels from gene-inactivated mice. The single deficiency of tPA, uPA, or uPAR, as well as combined deficiencies of uPA and tPA, did not dramatically affect microvessel formation. Deficiency of plasminogen delayed microvessel outgrowth. Lack of PAI-1 completely abolished angiogenesis, demonstrating its importance in the control of plasmin-mediated proteolysis. Microvessel outgrowth from PAI-1-/- aortic rings could be restored by adding exogenous PAI-1 (wild-type serum or purified recombinant PAI-1). Addition of recombinant PAI-1 led to a bell-shaped angiogenic response clearly showing that PAI-1 is proangiogenic at physiological concentrations and antiangiogenic at higher levels. Using specific PAI-1 mutants, we could demonstrate that PAI-1 promotes angiogenesis at physiological (nanomolar) concentrations through its antiproteolytic activity rather than by interacting with vitronectin.


Assuntos
Neovascularização Fisiológica/efeitos dos fármacos , Inibidor 1 de Ativador de Plasminogênio/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/crescimento & desenvolvimento , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/crescimento & desenvolvimento , Técnicas de Cultura , Relação Dose-Resposta a Droga , Feminino , Genótipo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/fisiologia , Receptores de Superfície Celular/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Ativador de Plasminogênio Tecidual/genética , Ativador de Plasminogênio Tipo Uroquinase/genética
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