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1.
N Engl J Med ; 390(18): 1677-1689, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38718358

RESUMEN

BACKGROUND: The use of thrombectomy in patients with acute stroke and a large infarct of unrestricted size has not been well studied. METHODS: We assigned, in a 1:1 ratio, patients with proximal cerebral vessel occlusion in the anterior circulation and a large infarct (as defined by an Alberta Stroke Program Early Computed Tomographic Score of ≤5; values range from 0 to 10) detected on magnetic resonance imaging or computed tomography within 6.5 hours after symptom onset to undergo endovascular thrombectomy and receive medical care (thrombectomy group) or to receive medical care alone (control group). The primary outcome was the score on the modified Rankin scale at 90 days (scores range from 0 to 6, with higher scores indicating greater disability). The primary safety outcome was death from any cause at 90 days, and an ancillary safety outcome was symptomatic intracerebral hemorrhage. RESULTS: A total of 333 patients were assigned to either the thrombectomy group (166 patients) or the control group (167 patients); 9 were excluded from the analysis because of consent withdrawal or legal reasons. The trial was stopped early because results of similar trials favored thrombectomy. Approximately 35% of the patients received thrombolysis therapy. The median modified Rankin scale score at 90 days was 4 in the thrombectomy group and 6 in the control group (generalized odds ratio, 1.63; 95% confidence interval [CI], 1.29 to 2.06; P<0.001). Death from any cause at 90 days occurred in 36.1% of the patients in the thrombectomy group and in 55.5% of those in the control group (adjusted relative risk, 0.65; 95% CI, 0.50 to 0.84), and the percentage of patients with symptomatic intracerebral hemorrhage was 9.6% and 5.7%, respectively (adjusted relative risk, 1.73; 95% CI, 0.78 to 4.68). Eleven procedure-related complications occurred in the thrombectomy group. CONCLUSIONS: In patients with acute stroke and a large infarct of unrestricted size, thrombectomy plus medical care resulted in better functional outcomes and lower mortality than medical care alone but led to a higher incidence of symptomatic intracerebral hemorrhage. (Funded by Montpellier University Hospital; LASTE ClinicalTrials.gov number, NCT03811769.).


Asunto(s)
Infarto de la Arteria Cerebral Anterior , Accidente Cerebrovascular , Trombectomía , Terapia Trombolítica , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Hemorragia Cerebral/etiología , Terapia Combinada , Procedimientos Endovasculares , Imagen por Resonancia Magnética , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/terapia , Terapia Trombolítica/efectos adversos , Terapia Trombolítica/métodos , Tomografía Computarizada por Rayos X , Infarto Encefálico/diagnóstico por imagen , Infarto Encefálico/etiología , Infarto Encefálico/terapia , Enfermedad Aguda , Arterias Cerebrales/diagnóstico por imagen , Arterias Cerebrales/cirugía , Enfermedades Arteriales Cerebrales/complicaciones , Enfermedades Arteriales Cerebrales/diagnóstico por imagen , Enfermedades Arteriales Cerebrales/patología , Enfermedades Arteriales Cerebrales/cirugía , Infarto de la Arteria Cerebral Anterior/diagnóstico por imagen , Infarto de la Arteria Cerebral Anterior/patología , Infarto de la Arteria Cerebral Anterior/cirugía
2.
Artículo en Inglés | MEDLINE | ID: mdl-37802919

RESUMEN

OBJECTIVE: There is limited evidence on when to obtain a central nervous system (CNS) biopsy in suspected primary angiitis of the central nervous system (PACNS). Our objective was to identify which clinical and radiological characteristics were associated with a positive biopsy in PACNS. METHODS: From the multicenter retrospective Cohort of Patients with Primary Vasculitis of the CNS (COVAC), we included adults with PACNS based on a positive CNS biopsy or otherwise unexplained intracranial stenoses with additional findings supportive of vasculitis. Baseline findings were compared between patients with a positive and negative biopsy using logistic regression models. RESULTS: 200 patients with PACNS were included, among which a biopsy was obtained in 100 (50%) and was positive in 61 (31%). Patients with a positive biopsy were more frequently female (OR 2.90, 95% CI 1.25-7.10, p = 0.01) and more often presented with seizures (OR 8.31, 95% CI 2.77-33.04, p < 0.001) or cognitive impairment (OR 2.58, 95% CI 1.11-6.10, p = 0.03). On imaging, biopsy positive patients more often had non-ischemic parenchymal or leptomeningeal gadolinium enhancement (OR 52.80, 95% CI 15.72-233.06, p < 0.001) or ≥ 1 cerebral microbleed (OR 8.08, 95% CI 3.03-25.13, p < 0.001), and less often had ≥ 1 acute brain infarct (OR 0.02, 95% CI 0.004-0.08, p < 0.001). In the multivariable model, non-ischemic parenchymal or leptomeningeal gadolinium enhancement (aOR 8.27, 95% CI 1.78-38.46), p < 0.01) and absence of ≥ 1 acute brain infarct (aOR 0.13, 95% CI 0.03-0.65, p = 0.01) were significantly associated with a positive biopsy. CONCLUSIONS: Baseline clinical and radiological characteristics differed between biopsy positive and negative PACNS. These results may help physicians individualize the decision to obtain a CNS biopsy in suspected PACNS.

3.
Brain Pathol ; 33(3): e13138, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36536531

RESUMEN

The diagnosis of neurodegenerative diseases is made complex by the heterogenous phenotype of the patients and the regular occurrence of concomitant pathology. Studying clinicopathological correlations in autopsy series is a central approach to improve pathological prediction in clinical practice. However, such method requires a wealth of information, and the use of standard spreadsheet software is hardly suitable. To overcome this constraint, we designed a customizable and freely available neuropathology form with 456 data entry fields driven by an open-source DataBase Management Systems (DBMS) using Structured Query Language (SQL). This approach allowed us to optimize the compilation of clinical and pathological data from our brain collection (264 autopsied patients, 22,885 data points). Information was then easily retrieved using general and specific queries, facilitating the analysis of demographics, clinicopathological correlations, and incidental and concomitant proteinopathies. Tau, amyloid-ß and α-synuclein incidental pathology was observed in respectively 78.1%, 42.8%, and 10.7% of all the patients. These proportions increased with age, reaching 100% for Tau pathology after 80. Concomitant proteinopathy was observed in 46.4% of the patients diagnosed with neurodegenerative diseases and prion disease. We observed a particularly high rate of co-pathology in patients with Dementia with Lewy bodies (81.3% of associated Tau and amyloid-ß pathology) and Creutzfeldt-Jakob disease (68.4% of associated Tau pathology). Finally, we used specific queries to identify old cases that could meet newly defined neuropathological criteria and revised the diagnosis of a 90-year-old patient to LATE Stage 2. Increasing our understanding of clinicopathological correlations in neurodegenerative diseases is crucial given the implications in clinical diagnosis, biomarker identification and targeted therapies assessment. The precise characterization of clinical and pathological data of autopsy series remains a central approach but the large amount of generated data should encourage a more systematic use of DBMS.


Asunto(s)
Enfermedad de Alzheimer , Síndrome de Creutzfeldt-Jakob , Enfermedades Neurodegenerativas , Sinucleinopatías , Humanos , Enfermedades Neurodegenerativas/patología , Cuerpos de Lewy/patología , Encéfalo/patología , Péptidos beta-Amiloides/metabolismo , Sinucleinopatías/patología , Proteínas tau/metabolismo , Enfermedad de Alzheimer/patología
4.
Stroke ; 52(1): 31-39, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33222617

RESUMEN

BACKGROUND AND PURPOSE: Acute ischemic stroke and large vessel occlusion can be concurrent with the coronavirus disease 2019 (COVID-19) infection. Outcomes after mechanical thrombectomy (MT) for large vessel occlusion in patients with COVID-19 are substantially unknown. Our aim was to study early outcomes after MT in patients with COVID-19. METHODS: Multicenter, European, cohort study involving 34 stroke centers in France, Italy, Spain, and Belgium. Data were collected between March 1, 2020 and May 5, 2020. Consecutive laboratory-confirmed COVID-19 cases with large vessel occlusion, who were treated with MT, were included. Primary investigated outcome: 30-day mortality. SECONDARY OUTCOMES: early neurological improvement (National Institutes of Health Stroke Scale improvement ≥8 points or 24 hours National Institutes of Health Stroke Scale 0-1), successful reperfusion (modified Thrombolysis in Cerebral Infarction grade ≥2b), and symptomatic intracranial hemorrhage. RESULTS: We evaluated 93 patients with COVID-19 with large vessel occlusion who underwent MT (median age, 71 years [interquartile range, 59-79]; 63 men [67.7%]). Median pretreatment National Institutes of Health Stroke Scale and Alberta Stroke Program Early CT Score were 17 (interquartile range, 11-21) and 8 (interquartile range, 7-9), respectively. Anterior circulation acute ischemic stroke represented 93.5% of cases. The rate modified Thrombolysis in Cerebral Infarction 2b to 3 was 79.6% (74 patients [95% CI, 71.3-87.8]). Thirty-day mortality was 29% (27 patients [95% CI, 20-39.4]). Early neurological improvement was 19.5% (17 patients [95% CI, 11.8-29.5]), and symptomatic intracranial hemorrhage was 5.4% (5 patients [95% CI, 1.7-12.1]). Patients who died at 30 days exhibited significantly lower lymphocyte count, higher levels of aspartate, and LDH (lactate dehydrogenase). After adjustment for age, initial National Institutes of Health Stroke Scale, Alberta Stroke Program Early CT Score, and successful reperfusion, these biological markers remained associated with increased odds of 30-day mortality (adjusted odds ratio of 2.70 [95% CI, 1.21-5.98] per SD-log decrease in lymphocyte count, 2.66 [95% CI, 1.22-5.77] per SD-log increase in aspartate, and 4.30 [95% CI, 1.43-12.91] per SD-log increase in LDH). CONCLUSIONS: The 29% rate of 30-day mortality after MT among patients with COVID-19 is not negligible. Abnormalities of lymphocyte count, LDH and aspartate may depict a patient's profiles with poorer outcomes after MT. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT04406090.


Asunto(s)
COVID-19/complicaciones , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico/complicaciones , Accidente Cerebrovascular Isquémico/cirugía , Trombectomía , Anciano , Anciano de 80 o más Años , COVID-19/epidemiología , Estudios de Cohortes , Procedimientos Endovasculares/mortalidad , Europa (Continente) , Femenino , Humanos , Accidente Cerebrovascular Isquémico/mortalidad , Masculino , Persona de Mediana Edad , Sistema de Registros , Factores de Riesgo , SARS-CoV-2 , Trombectomía/mortalidad , Resultado del Tratamiento
5.
Stroke ; 47(9): 2401-4, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27470990

RESUMEN

BACKGROUND AND PURPOSE: We aimed to describe the clinical and imaging features of patients with tumor-like presentation of primary angiitis of the central nervous system. METHODS: We retrospectively analyzed 10 patients enrolled in the French primary angiitis of the central nervous system cohort, who initially presented tumor-like brain lesions and compared them with other patients within the cohort. RESULTS: The 10 patients with tumor-like presentation in the cohort were younger and had more seizures at diagnosis than the other 75 patients (median of 37 [30-48] years versus 46 [18-79] years; P=0.008; 9 [90%] with seizures versus 22 [29%], P<0.001; respectively). All 10 patients had a biopsy (stereotactic procedure in 7 and open-wedge surgery in 3). Histological findings suggestive of vasculitis were observed in 9 patients in whom conventional cerebral angiography and magnetic resonance angiography were negative. In the remaining patient, vascular imaging demonstrated diffuse bilateral large- and medium-sized vessel involvement (biopsy did not reveal vasculitis). All patients with tumor-like presentation received glucocorticoids, combined with cyclophosphamide in 9 cases. With a median follow-up of 27 (12-130) months, 5 (50%) patients relapsed, but achieved remission again after treatment intensification. CONCLUSIONS: Patients with tumor-like presentation of primary angiitis of the central nervous system represent a subgroup characterized with mainly small-sized vessel disease that requires histological confirmation because vascular imaging is often normal. Although relapses are not uncommon, global outcomes are good under treatment with glucocorticoids and cyclophosphamide.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Encéfalo/patología , Vasculitis del Sistema Nervioso Central/diagnóstico , Adolescente , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Angiografía Cerebral , Diagnóstico Diferencial , Femenino , Humanos , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Vasculitis del Sistema Nervioso Central/diagnóstico por imagen , Vasculitis del Sistema Nervioso Central/patología , Adulto Joven
6.
PLoS One ; 11(3): e0149466, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27023901

RESUMEN

BACKGROUND: Extended immobility has been associated with medical complications during hospitalization. However no clear recommendations are available for mobilization of ischemic stroke patients. OBJECTIVE: As early mobilization has been shown to be feasible and safe, we tested the hypothesis that early sitting could be beneficial to stroke patient outcome. METHODS: This prospective multicenter study tested two sitting procedures at the acute phase of ischemic stroke, in a randomized controlled fashion (clinicaltrials.org registration number NCT01573299). Patients were eligible if they were above 18 years of age and showed no sign of massive infarction or any contra-indication for sitting. In the early-sitting group, patients were seated out of bed at the earliest possible time but no later than one calendar day after stroke onset, whereas the progressively-sitting group was first seated out of bed on the third calendar day after stroke onset. Primary outcome measure was the proportion of patients with a modified Rankin score [0-2] at 3 months post stroke. Secondary outcome measures were a.) prevalence of medical complications, b.) length of hospital stay, and c.) tolerance to the procedure. RESULTS: One hundred sixty seven patients were included in the study, of which 29 were excluded after randomization. Data from 138 patients, 63 in the early-sitting group and 75 in the progressively-sitting group were analyzed. There was no difference regarding outcome of people with stroke, with a proportion of Rankin [0-2] score at 3 months of 76.2% and 77.3% of patients in the early- and progressive-sitting groups, respectively (p = 0.52). There was also no difference between groups for secondary outcome measures, and the procedure was well tolerated in both arms. CONCLUSION: Due to a slow enrollment, fewer patients than anticipated were available for analysis. As a result, we can only detect beneficial/detrimental effects of +/- 15% of the early sitting procedure on stroke outcome with a realized 37% power. However, enrollment was sufficient to rule out effect sizes greater than 25% with 80% power, indicating that early sitting is unlikely to have an extreme effect in either direction on stroke outcome. Additionally, we were not able to provide a blinded assessment of the primary outcome. Taking these limitations into account, our results may help guide the development of more effective acute stroke rehabilitation strategies, and the design of future acute stroke trials involving out of bed activities and other mobilization regimens. TRIAL REGISTRATION: ClinicalTrials.gov NCT01573299.


Asunto(s)
Isquemia Encefálica/complicaciones , Postura , Accidente Cerebrovascular/complicaciones , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
7.
Ann Vasc Surg ; 28(6): 1539-47, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24530723

RESUMEN

BACKGROUND: The objective of this exploratory study was to determine the rate of the complications of early surgery for symptomatic carotid stenosis, in 2 centers of Western France. METHODS: Between January 2011 and January 2013, we prospectively enrolled all the patients admitted for transient ischemic accident (TIA) or minor stroke (Rankin ≤ 3) associated with an ipsilateral carotid stenosis >50% (North American Symptomatic Carotid Endarterectomy Trial) and operated before the 14th day following the neurologic event at the University hospitals of Angers and Tours. The demographic data (gender, age, and medical history) and the characteristics of the procedures were recorded. The rates of stroke, TIA, and postoperative deaths defined the cumulative morbidity and mortality rate (CMMR) of the study. RESULTS: Ninety-one patients were included in the study. They presented 27 TIAs and 64 strokes. The average elapsed time between the neurologic event and surgery was 9.8 days. During this time, 10 patients, that is, 11% of the operated cohort, presented a new ischemic neurologic event while waiting for surgery. Surgical operations consisted of 56 eversions (61.5%), 32 endarterectomies with patch (35.1%), 2 bypasses, and 1 direct closure. The CMMR reached 3.3%. Two patients presented with a stroke and 1 patient died of a cardiologic cause during the postoperative period. CONCLUSIONS: This study confirms the interest of an early surgery for symptomatic carotid stenoses with a Rankin score of ≤3. The risk of recurrence of a cerebral ischemic accident during the preoperative period remains high.


Asunto(s)
Estenosis Carotídea/cirugía , Ataque Isquémico Transitorio/etiología , Accidente Cerebrovascular/etiología , Tiempo de Tratamiento , Procedimientos Quirúrgicos Vasculares , Anciano , Anciano de 80 o más Años , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico , Estenosis Carotídea/mortalidad , Femenino , Francia , Hospitales de Enseñanza , Humanos , Ataque Isquémico Transitorio/diagnóstico , Ataque Isquémico Transitorio/mortalidad , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recurrencia , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/mortalidad , Factores de Tiempo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos , Procedimientos Quirúrgicos Vasculares/mortalidad
8.
Plant Physiol Biochem ; 60: 74-80, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22906813

RESUMEN

Plasmopara viticola must successfully infect susceptible grapevine cultivars to complete its biological cycle. In resistant grapevine varieties, P. viticola is blocked by the activation of defense mechanisms; these defense mechanisms produce hypersensitive reactions, which are related to programmed cell death. In animals, programmed cell death is dependent on caspase activities. In plants, different caspase-like proteases assume the same functions. To examine the roles of caspase-like proteases in P. viticola-grapevine interactions, three varieties of grapevine with different levels of P. viticola resistance were chosen. These grapevine varieties were treated with either PMSF, a serine protease inhibitor, or E-64, a cysteine protease inhibitor. The development of the pathogen was followed microscopically, and the plant defense reactions were estimated through stilbene quantification. Both protease inhibitor treatments increased the infection rate in the resistant and immune varieties, diminished the production of toxic stilbenes and changed the level of the plants' susceptibility to the pathogen. In particular, after either protease treatment, the cultivar that was originally immune became resistant (hyphae and haustoria were observed), the resistant cultivar reached the level of a susceptible cultivar (sporulation was observed) and the susceptible cultivar became more sensitive (P. viticola colonized the entirety of the leaf mesophyll).


Asunto(s)
Resistencia a la Enfermedad/efectos de los fármacos , Oomicetos/fisiología , Enfermedades de las Plantas/inmunología , Inhibidores de Proteasas/farmacología , Estilbenos/metabolismo , Vitaceae/efectos de los fármacos , Animales , Apoptosis , Inhibidores de Cisteína Proteinasa/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Interacciones Huésped-Parásitos , Leucina/análogos & derivados , Leucina/farmacología , Microscopía Electrónica de Transmisión , Microscopía Fluorescente , Fluoruro de Fenilmetilsulfonilo/farmacología , Enfermedades de las Plantas/parasitología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/inmunología , Hojas de la Planta/parasitología , Hojas de la Planta/ultraestructura , Estomas de Plantas/efectos de los fármacos , Estomas de Plantas/inmunología , Estomas de Plantas/parasitología , Estomas de Plantas/ultraestructura , Inhibidores de Serina Proteinasa/farmacología , Estilbenos/análisis , Vitaceae/inmunología , Vitaceae/parasitología , Vitaceae/ultraestructura
9.
Plant Physiol Biochem ; 47(9): 827-37, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19447634

RESUMEN

The ability of two plant extracts, Rheum palmatum root extract (RPRE) and Frangula alnus bark extract (FABE), to protect Vitis vinifera leaves from Plasmopara viticola infection was evaluated. These natural products are toxic to the pathogen and induce defence reactions in a susceptible cultivar of V. vinifera (V. vinifera cv. Chasselas), including stilbenic phytoalexin accumulation, enhanced peroxidase (EC 1.11.1.7) activity, and a hypersensitive reaction. Inhibition of the first stage of biotrophic hyphal development of P. Viticola by the two plant extracts was observed. HPLC-DAD-MS analysis showed that these two natural extracts contain many phenolic compounds belonging to the anthraquinone family, such as rhein, frangulin A, emodin, aloe-emodin, chrysophanol, and physcion. Emodin alone is able to impair P. viticola development and to stimulate viniferins and the accumulation of pterostilbene.


Asunto(s)
Antraquinonas/química , Emodina/química , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Cromatografía/métodos , Cromatografía Líquida de Alta Presión , Emodina/farmacología , Espectrometría de Masas/métodos , Modelos Biológicos , Peroxidasas/metabolismo , Fenómenos Fisiológicos de las Plantas , Especies Reactivas de Oxígeno , Resveratrol , Solventes/química , Estilbenos/química , Estilbenos/farmacología , Factores de Tiempo
10.
Oncogene ; 23(41): 6854-63, 2004 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-15273738

RESUMEN

Amplification of the epidermal growth factor receptor (EGFR) or expression of its constitutively activated mutant, DeltaEGFR(2-7), in association with the inactivation of the INK4a/Arf gene locus is a frequent alteration in human glioblastoma. The notion of a cooperative effect between these two alterations has been demonstrated in respective mouse brain tumor models including our own. Here, we investigated underlying molecular mechanisms in early passage cortical astrocytes deficient for p16(INK4a)/p19(Arf) or p53, respectively, with or without ectopic expression of DeltaEGFR(2-7). Targeting these cells with the specific EGFR inhibitor tyrphostin AG1478 revealed that phosphorylation of ERK was only abrogated in the presence of an intact INK4a/Arf gene locus. The sensitivity to inhibit ERK phosphorylation was independent of ectopic expression of DeltaEGFR(2-7) and independent of the TP53 status. This resistance to downregulate the MAPK pathway in the absence of INK4a/Arf was confirmed in cell lines derived from our mouse glioma models with the respective initial genetic alterations. Thus, deletion of INK4a/Arf appears to keep ERK in its active, phosphorylated state insensitive to an upstream inhibitor specifically targeting EGFR/DeltaEGFR(2-7). This resistance may contribute to the cooperative tumorigenic effect selected for in human glioblastoma that may be of crucial clinical relevance for treatments specifically targeting EGFR/DeltaEGFR(2-7) in glioblastoma patients.


Asunto(s)
Astrocitos/enzimología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/fisiología , Receptores ErbB/antagonistas & inhibidores , Glioma/enzimología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Animales , Activación Enzimática , Ratones , Fosforilación , Quinazolinas , Tirfostinos/farmacología
11.
Clin Cancer Res ; 10(6): 1871-4, 2004 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15041700

RESUMEN

PURPOSE: In the setting of a prospective clinical trial, we determined the predictive value of the methylation status of the O-6-methylguanine-DNA methyltransferase (MGMT) promoter for outcome in glioblastoma patients treated with the alkylating agent temozolomide. Expression of this excision repair enzyme has been associated with resistance to alkylating chemotherapy. EXPERIMENTAL DESIGN: The methylation status of MGMT in the tumor biopsies was evaluated in 38 patients undergoing resection for newly diagnosed glioblastoma and enrolled in a Phase II trial testing concomitant and adjuvant temozolomide and radiation. The epigenetic silencing of the MGMT gene was determined using methylation-specific PCR. RESULTS: Inactivation of the MGMT gene by promoter methylation was associated with longer survival (P = 0.0051; Log-rank test). At 18 months, survival was 62% (16 of 26) for patients testing positive for a methylated MGMT promoter but reached only 8% (1 of 12) in absence of methylation (P = 0.002; Fisher's exact test). In the presence of other clinically relevant factors, methylation of the MGMT promoter remains the only significant predictor (P = 0.017; Cox regression). CONCLUSIONS: This prospective clinical trial identifies MGMT-methylation status as an independent predictor for glioblastoma patients treated with a methylating agent. The association of the epigenetic inactivation of the DNA repair gene MGMT with better outcome in this homogenous cohort may have important implications for the design of future trials and supports efforts to deplete MGMT by O-6-benzylguanine, a noncytotoxic substrate of this enzyme.


Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Metilación de ADN , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , O(6)-Metilguanina-ADN Metiltransferasa/genética , Regiones Promotoras Genéticas/genética , Adulto , Anciano , Antineoplásicos Alquilantes/toxicidad , Biopsia , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Terapia Combinada , Dacarbazina/toxicidad , Femenino , Glioblastoma/mortalidad , Glioblastoma/patología , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Análisis de Supervivencia , Temozolomida , Factores de Tiempo
12.
Cancer Res ; 63(20): 6613-25, 2003 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-14583454

RESUMEN

The development of targeted treatment strategies adapted to individual patients requires identification of the different tumor classes according to their biology and prognosis. We focus here on the molecular aspects underlying these differences, in terms of sets of genes that control pathogenesis of the different subtypes of astrocytic glioma. By performing cDNA-array analysis of 53 patient biopsies, comprising low-grade astrocytoma, secondary glioblastoma (respective recurrent high-grade tumors), and newly diagnosed primary glioblastoma, we demonstrate that human gliomas can be differentiated according to their gene expression. We found that low-grade astrocytoma have the most specific and similar expression profiles, whereas primary glioblastoma exhibit much larger variation between tumors. Secondary glioblastoma display features of both other groups. We identified several sets of genes with relatively highly correlated expression within groups that: (a). can be associated with specific biological functions; and (b). effectively differentiate tumor class. One prominent gene cluster discriminating primary versus nonprimary glioblastoma comprises mostly genes involved in angiogenesis, including VEGF fms-related tyrosine kinase 1 but also IGFBP2, that has not yet been directly linked to angiogenesis. In situ hybridization demonstrating coexpression of IGFBP2 and VEGF in pseudopalisading cells surrounding tumor necrosis provided further evidence for a possible involvement of IGFBP2 in angiogenesis. The separating groups of genes were found by the unsupervised coupled two-way clustering method, and their classification power was validated by a supervised construction of a nearly perfect glioma classifier.


Asunto(s)
Astrocitoma/genética , Neoplasias Encefálicas/genética , Neovascularización Patológica/genética , Adolescente , Adulto , Anciano , Astrocitoma/irrigación sanguínea , Astrocitoma/metabolismo , Astrocitoma/patología , Neoplasias Encefálicas/irrigación sanguínea , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Hipoxia de la Célula/fisiología , Preescolar , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/biosíntesis , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Masculino , Persona de Mediana Edad , Familia de Multigenes , Análisis de Secuencia por Matrices de Oligonucleótidos , Reproducibilidad de los Resultados
13.
Oncogene ; 21(27): 4212-9, 2002 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-12082608

RESUMEN

Human astrocytic brain tumors select for mutations in the p53 tumor suppressor gene early in malignant progression. p53 is activated upon various kinds of cellular stress leading to apoptosis or cell cycle arrest, but is also implicated in complex biological processes such as inhibition of angiogenesis and metastasis. In an effort to shed light on consequences mediated by p53 inactivation in gliomas, we established the Tet-On system for p53 in the LN-Z308 glioblastoma cell line. The macrophage inhibitory cytokine-1 (MIC-1) gene was identified as a most prominent p53 target gene upon gene expression profiling. Oxygen deprivation, an important cellular stress, revealed MIC-1 as an anoxia responsive gene in glioblastoma cell lines. MIC-1 up-regulation by anoxia is mediated through an alternative, p53 and hypoxia inducible factor 1 (HIF-1) independent pathway. Furthermore, ectopic expression of MIC-1 in LN-Z308 cell line completely abolished its inherent tumorigenicity in nude mice, while proliferation in vitro was not affected. In the present experimental model MIC-1 may exert its anti-tumorigenic properties via a paracrine mechanism mediated by host cells in vivo. Taken together, these data suggest that MIC-1 is an important downstream mediator of p53 function, while acting itself as an intercessor of cellular stress signaling and exerting anti-tumorigenic activities.


Asunto(s)
Neoplasias Encefálicas/patología , Citocinas/biosíntesis , Proteínas de Unión al ADN/fisiología , Regulación Neoplásica de la Expresión Génica , Glioblastoma/patología , Proteínas de Neoplasias/biosíntesis , Proteínas Nucleares/fisiología , Oxígeno/farmacología , Factores de Transcripción , Proteína p53 Supresora de Tumor/fisiología , Animales , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Hipoxia de la Célula/genética , Citocinas/genética , Dexametasona/farmacología , Doxiciclina/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes p53 , Glioblastoma/genética , Glioblastoma/metabolismo , Factor 15 de Diferenciación de Crecimiento , Humanos , Factor 1 Inducible por Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia , Ratones , Ratones Desnudos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiología , Trasplante de Neoplasias , Proteínas Recombinantes de Fusión/fisiología , Transducción de Señal , Trasplante Heterólogo
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