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1.
Rev Neurol (Paris) ; 179(5): 490-501, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36964121

RESUMO

Glioblastoma (GB) is the most common and aggressive primary brain tumor, with poor patient survival and lack of effective therapies. Late advances trying to decipher the composition of the GB tumor microenvironment (TME) emphasized its role in tumor progression and potentialized it as a therapeutic target. Many components participate critically to tumor development and expansion such as blood vessels, immune cells or components of the nervous system. Dysmorphic tumor vasculature brings challenges to optimal delivery of cytotoxic agents currently used in clinics. Also, massive infiltration of immunosuppressive myeloid cells and limited recruitment of T cells limits the success of conventional immunotherapies. Neuronal input seems also be required for tumor expansion. In this review, we provide a comprehensive report of vascular and immune component of the GB TME and their cross talk during GB progression.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Neoplasias Encefálicas/terapia , Microambiente Tumoral
2.
Oncogene ; 33(31): 4060-8, 2014 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-24166504

RESUMO

The glycolytic end-product lactate is a pleiotropic tumor growth-promoting factor. Its activities primarily depend on its uptake, a process facilitated by the lactate-proton symporter monocarboxylate transporter 1 (MCT1). Therefore, targeting the transporter or its chaperon protein CD147/basigin, itself involved in the aggressive malignant phenotype, is an attractive therapeutic option for cancer, but basic information is still lacking regarding the regulation of the expression, interaction and activities of both proteins. In this study, we found that glucose deprivation dose-dependently upregulates MCT1 and CD147 protein expression and their interaction in oxidative tumor cells. While this posttranslational induction could be recapitulated using glycolysis inhibition, hypoxia, oxidative phosphorylation (OXPHOS) inhibitor rotenone or hydrogen peroxide, it was blocked with alternative oxidative substrates and specific antioxidants, pointing out at a mitochondrial control. Indeed, we found that the stabilization of MCT1 and CD147 proteins upon glucose removal depends on mitochondrial impairment and the associated generation of reactive oxygen species. When glucose was a limited resource (a situation occurring naturally or during the treatment of many tumors), MCT1-CD147 heterocomplexes accumulated, including in cell protrusions of the plasma membrane. It endowed oxidative tumor cells with increased migratory capacities towards glucose. Migration increased in cells overexpressing MCT1 and CD147, but it was inhibited in glucose-starved cells provided with an alternative oxidative fuel, treated with an antioxidant, lacking MCT1 expression, or submitted to pharmacological MCT1 inhibition. While our study identifies the mitochondrion as a glucose sensor promoting tumor cell migration, MCT1 is also revealed as a transducer of this response, providing a new rationale for the use of MCT1 inhibitors in cancer.


Assuntos
Basigina/metabolismo , Movimento Celular , Glucose/metabolismo , Mitocôndrias/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Simportadores/metabolismo , Neoplasias do Colo do Útero/metabolismo , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Glicólise/fisiologia , Células HeLa , Humanos , Mitocôndrias/genética , Transportadores de Ácidos Monocarboxílicos/genética , Simportadores/genética
3.
Oncogene ; 30(17): 2070-6, 2011 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-21170089

RESUMO

Na(V)1.5 sodium channels enhance the invasiveness of breast cancer cells through the acidic-dependent activation of cysteine cathepsins. Here, we showed that the Na(+)/H(+) exchanger type 1 (NHE1) was an important regulator of H(+) efflux in breast cancer cells MDA-MB-231 and that its activity was increased by Na(V)1.5. Na(V)1.5 and NHE1 were colocalized in membrane rafts containing caveolin-1. The inhibition of Na(V)1.5 or NHE1 induced a similar reduction in cell invasiveness and extracellular matrix degradation; no additive effect was observed when they were simultaneously inhibited. Our study suggests that Na(V)1.5 and NHE1 are functionally coupled and enhance the invasiveness of cancer cells by increasing H(+) efflux.


Assuntos
Neoplasias da Mama/patologia , Proteínas de Transporte de Cátions/metabolismo , Cavéolas/metabolismo , Proteínas Musculares/metabolismo , Prótons , Canais de Sódio/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Transporte Biológico , Proteínas de Transporte de Cátions/genética , Linhagem Celular Tumoral , Humanos , Concentração de Íons de Hidrogênio , Espaço Intracelular/química , Espaço Intracelular/metabolismo , Proteínas Musculares/genética , Canal de Sódio Disparado por Voltagem NAV1.5 , Invasividade Neoplásica , Transporte Proteico , Canais de Sódio/genética , Trocador 1 de Sódio-Hidrogênio , Trocadores de Sódio-Hidrogênio/genética
4.
Med Pediatr Oncol ; 36(1): 157-9, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11464873

RESUMO

BACKGROUND: Neuroblastoma has several characteristics that suggest that preclinical diagnosis might improve outcome. Therefore, the Quebec Neuroblastoma Screening Project was undertaken from 1989 to 1994 to examine infants at 3 weeks and 6 months by measuring urinary catecholamine metabolites. PROCEDURE: Over the 5-yr period, 45 tumors were detected by screening, 20 were identified clinically prior to the third week, and 64 were identified clinically at a later time. We analyzed available tumors for Shimada histopathology, tumor ploidy, MYCN copy number and serum ferritin. RESULTS: Of the tumors detected by screening, only 2 of 45 tested had unfavorable histology, 2 of 45 had diploid or tetraploid DNA content, 0 of 43 had MYCN amplification, and 4 of 44 had elevated serum ferritin. All of these patients are alive and well. The 20 patients detected prior to the 3-week screen had similar biological characteristics. In contrast, of the patients detected clinically after 3 weeks of age, 19 of 51 testedhad unfavorable histology, 25 of 66 had diploid or tetraploid tumors, 12 of 56 had MYCN amplification, and 14 of 54 had elevated ferritin. CONCLUSIONS: The difference between the screened and clinically detected cases was highly significant for each biological variable. Preliminary data on other biological variables, such as neurotrophin expression and allelic loss on 1 p in these patients are consistent with the above findings. These data suggest that mass screening for neuroblastoma at or before 6 months of age detects almost exclusively tumors that have favorable biological characteristics, many of which might have regressed spontaneously. Thus, continued mass screening for neuroblastoma at 6 months is unlikely to accomplish its intended goal, and should probably be discontinued.


Assuntos
Programas de Rastreamento , Neuroblastoma/epidemiologia , Fatores Etários , Biomarcadores Tumorais , Catecolaminas/urina , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 1/ultraestrutura , Estudos de Coortes , Ferritinas/análise , Ferritinas/sangue , Amplificação de Genes , Genes myc , Humanos , Lactente , Recém-Nascido , Triagem Neonatal , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Exame Físico , Ploidias , Prognóstico , Quebeque/epidemiologia
5.
Pediatr Res ; 47(6): 763-6, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10832734

RESUMO

The outcome for children with deep vein thrombosis (DVT) and pulmonary embolism (PE) is unknown. An understanding of morbidity and mortality of DVT/PE is crucial to the development of rational treatment protocols. The Canadian Childhood Thrombophilia Registry has followed 405 children aged 1 mo to 18 y with DVT/PE for a mean of 2.86 y (range, 2 wk to 6 y) to assess outcome. The all-cause mortality was 65 of 405 children (16%). Mortality directly attributable to DVT/PE occurred in nine children (2.2%), all of whom had central venous line-associated thrombosis. Morbidity was substantial, with 33 children (8.1%) having recurrent thrombosis, and 50 children (12.4%) having postphlebitic syndrome. Recurrent thrombosis and postphlebitic syndrome were more common in older children, although deaths occurred equally in all age groups. The incidence of recurrent thrombosis and postphlebitic syndrome are likely underestimated because of difficulties in diagnosis, especially in younger children. The significant mortality and morbidity found in our study supports the need for international multicenter randomized clinical trials to determine optimal prophylactic and therapeutic treatment for children with DVT/PE.


Assuntos
Tromboembolia/fisiopatologia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Humanos , Lactente , Recém-Nascido , Recidiva , Sistema de Registros , Tromboembolia/etiologia , Tromboembolia/mortalidade , Resultado do Tratamento
6.
Cancer ; 83(3): 575-81, 1998 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9690552

RESUMO

BACKGROUND: The Quebec Neuroblastoma Screening (QNS) Project completed a 5-year program for measuring urinary vanillylmandelic acid (VMA)/homovanillic acid (HVA) levels at age 3 weeks and/or 6 months in 89% of 476,603 Quebec-born infants from 1989-1994; 45 screening positive preclinical cases (S-positive cases) and 20 congenital/neonatal (C/N) cases were identified. As of April 1997, an additional 59 cases in the same birth cohort were diagnosed clinically; these neuroblastomas developed after screening verified normal VMA/HVA levels (S-negative cases). METHODS: Pathology specimens from 45 of 59 S-negative cases were reviewed centrally and classified according to the Shimada system. Results were compared with clinical data and also with S-positive and C/N cases. RESULTS: Of 45 S-negative cases, 27 tumors had favorable histology (FH) and 18 had unfavorable histology (UH). Approximately 52% of FH tumors were diagnosed before age 1 year, whereas UH tumors were nearly exclusively (94%) diagnosed after age 1 year (P < 0.01). Approximately 89% of FH tumors were Stage I, II, or IV-S, whereas 72% UH tumors were Stage III or IV (P < 0.001). All children with FH tumors were alive at last follow-up (range of follow-up period: 9-79 months; median, 35 months), whereas 8 children with UH tumors died of disease even after limited follow-up (range of follow-up period: 0-60 months; median, 20 months). By contrast, S-positive and C/N cases were predominantly (97%) FH tumors, often (76%) Stage I, II, or IV-S, with excellent clinical outcome (survival rate of 98%). CONCLUSIONS: The majority of the UH neuroblastomas that developed in the birth cohort of the QNS Project were included in the group of S-negative cases and could not be detected by the screening at age 3 weeks and/or 6 months.


Assuntos
Neuroblastoma/patologia , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Programas de Rastreamento , Neuroblastoma/mortalidade
7.
Plant Physiol ; 116(1): 259-69, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9449845

RESUMO

Constructs containing the cDNAs encoding the primary leaf catalase in Nicotiana or subunit 1 of cottonseed (Gossypium hirsutum) catalase were introduced in the sense and antisense orientation into the Nicotiana tabacum genome. The N. tabacum leaf cDNA specifically overexpressed CAT-1, the high catalatic [corrected] form, activity. Antisense constructs reduced leaf catalase specific activities from 0.20 to 0.75 times those of wild type (WT), and overexpression constructs increased catalase specific activities from 1.25 to more than 2.0 times those of WT. The NADH-hydroxypyruvate reductase specific activity in transgenic plants was similar to that in WT. The effect of antisense constructs on photorespiration was studied in transgenic plants by measuring the CO2 compensation point (gamma) at a leaf temperature of 38 degrees C. A significant linear increase was observed in gamma with decreasing catalase (at 50% lower catalase activity gamma increased 39%). There was a significant temperature-dependent linear decrease in gamma in transgenic leaves with elevated catalase compared with WT leaves (at 50% higher catalase gamma decreased 17%). At 29 degrees C, gamma also decreased with increasing catalase in transgenic leaves compared with WT leaves, but the trend was not statistically significant. Rates of dark respiration were the same in WT and transgenic leaves. Thus, photorespiratory losses of CO2 were significantly reduced with increasing catalase activities at 38 degrees C, indicating that the stoichiometry of photorespiratory CO2 formation per glycolate oxidized normally increases at higher temperatures because of enhanced peroxidation.


Assuntos
Catalase/biossíntese , Gossypium/enzimologia , Nicotiana/metabolismo , Fotossíntese , Plantas Tóxicas , Oxirredutases do Álcool/metabolismo , Clonagem Molecular , DNA Antissenso , DNA Complementar , Gossypium/genética , Concentração de Íons de Hidrogênio , Hidroxipiruvato Redutase , Isoenzimas/biossíntese , Consumo de Oxigênio , Folhas de Planta , Plantas Geneticamente Modificadas , Temperatura
8.
Biochem Cell Biol ; 75(4): 457-61, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9493969

RESUMO

An emerging family of bcl-2-like genes has been identified from nematode to humans. These genes play a role in the maintenance of homeostasis. Its members have highly conserved domains that are important for their dimerization. Since nothing is known about the importance of these genes in plant cells, we have investigated their presence in an alga as well as in three higher plants both by Western analysis and by immunocytochemistry. Immunoblots revealed the presence of a protein immunoreacting with the anti-bcl-2 polyclonal antibody in leaves of tobacco plants. Furthermore, immunocytochemical localization has shown that this protein is mainly associated with mitochondria, plastids, and nuclei of plant cells. Taken together, our results suggest that bcl-2 is a protein highly conserved throughout evolution.


Assuntos
Genes bcl-2/genética , Proteínas de Plantas/genética , Homologia de Sequência do Ácido Nucleico , Animais , Anticorpos/metabolismo , Especificidade de Anticorpos , Brassica , Linhagem Celular , Núcleo Celular/química , Núcleo Celular/ultraestrutura , Chlamydomonas reinhardtii , Linfócitos , Camundongos , Mitocôndrias/química , Mitocôndrias/ultraestrutura , Proteínas de Plantas/imunologia , Plantas Tóxicas , Ratos , Nicotiana , Zea mays
9.
Eur J Cancer ; 33(12): 2106-12, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9516863

RESUMO

Neuroblastoma exhibits many characteristics which would suggest that preclinical detection may improve outcome. The Quebec Neuroblastoma Screening Project was initiated to determine whether mass screening could reduce mortality in a large cohort of infants. All 476,603 children born in the province of Quebec during a 5-year period of time (1 May 1989 to 30 April 1994) were eligible for determinations of urinary catecholamine metabolites at 3 weeks and 6 months of age. Children with positive screening were referred to one of four paediatric cancer centres in Quebec for uniform evaluation and treatment. Standardised incidence ratios (SIRs) were calculated for neuroblastoma in Quebec and two comparable population-based controls during the same period of time using similar ascertainment procedures. Compliance with screening in Quebec was 91% at 3 weeks (n = 425,816) and 74% at 6 months (n = 349,706). Up to 31 July 1995 with a follow-up of the birth cohort of 15-75 months, 118 cases of neuroblastoma were diagnosed, 43 detected preclinically by screening, 20 detected clinically prior to screening at 3 weeks of age and 55 detected clinically after 3 weeks of age having normal screens (n = 52) or never screened (n = 3). Based on data from concurrent control populations, 54.5 cases of neuroblastoma would have been expected in Quebec during the study period for an SIR of 2.17 (95% CI 1.79-2.57, P < 0.0001). For the two control groups, the overall SIR was 1.00 (NS). SIRs for Quebec by age at diagnosis in yearly intervals show a marked increased incidence under 1 year of age (SIR = 2.85, 95% CI 2.26-3.50), with no reduction in incidence in subsequent years. We conclude that screening for neuroblastoma markedly increases the incidence in infants without decreasing the incidence of unfavourable advanced stage disease in older children. It is unlikely that screening for neuroblastoma in infants will reduce the mortality of this disease.


Assuntos
Programas de Rastreamento , Neuroblastoma/prevenção & controle , Canadá/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Seguimentos , Humanos , Incidência , Lactente , Recém-Nascido , Estadiamento de Neoplasias , Neuroblastoma/epidemiologia , Neuroblastoma/patologia , Cooperação do Paciente
10.
Lancet ; 348(9043): 1682-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8973429

RESUMO

BACKGROUND: Neuroblastoma has many characteristics which suggest that preclinical detection might improve outcome. The Quebec Neuroblastoma Screening Project was initiated to determine whether mass screening could reduce mortality in a large cohort of infants. As an early endpoint, we report whether screening could reduce the incidence of poor-prognosis neuroblastoma in children with advanced-stage disease over 1 year of age. METHODS: All 476,603 children born in the province of Quebec during the 5-year period of May 1, 1989, to April 30, 1994, were eligible for urinary assay of homovanillic acid and vanillylmandelic acid at 3 weeks and 6 months of age. Children with a positive screen were referred to one of four paediatric cancer centres in the province for uniform evaluation and treatment if necessary. Standardised incidence ratios (SIRs) were calculated for neuroblastoma in the province and two similar population-based controls, the state of Minnesota and the province of Ontario, during the same period of time and with similar ascertainment procedures. FINDINGS: Compliance with screening in Quebec province was 91% at 3 weeks (n = 425,816) and 74% at 6 months (n = 349,706). Through July 31, 1995, with a follow-up of the birth cohort of 15-75 months, 118 cases of neuroblastoma were diagnosed, 43 detected preclinically by screening, 20 detected clinically before screening at 3 weeks of age, and 55 detected clinically after 3 weeks of age having normal screens (52) or never screened (3). Retrospective analysis of stored samples confirmed that 49 of 52 patients missed by screening had levels of catecholamine metabolites that were too low to be detected at 6 months or earlier. Based on US Surveillance, Epidemiology and End Results data, 54.5 cases of neuroblastoma would have been expected in Quebec province during the study period, for an SIR of 2.17 (95% CI 1.79-2.57, p < 0.0001). For the two control groups, 43 and 80 cases of neuroblastoma were detected, respectively, compared with 37.9 and 85.4 expected, overall SIR 1.00 (not significant). SIRs for Quebec province by age at diagnosis in yearly intervals show a marked increased incidence under 1 year of age (SIR 2.85, 2.26-3.50), with no reduction in incidence in subsequent years. Limiting analysis to only patients diagnosed over 1 year of age with advanced-stage disease, 22 cases were detected in Quebec province versus 14.4 expected (SIR 1.52, 0.95-2.23). Data in the two control groups show no significant increase or decrease in any-stage disease in children under or over the age of 1 year, except for an increase in early-stage disease in Minnesota children over 1 year: 10 versus 3.8 expected (SIR 2.67, 1.27-4.58). INTERPRETATION: Screening for neuroblastoma increases the incidence in infants without decreasing the incidence of unfavourable advanced-stage disease in older children. It is unlikely that screening for neuroblastoma in infants will reduce mortality for this disease.


Assuntos
Programas de Rastreamento , Neuroblastoma/prevenção & controle , Cromatografia em Camada Fina , Estudos de Coortes , Cromatografia Gasosa-Espectrometria de Massas , Ácido Homovanílico/urina , Humanos , Incidência , Lactente , Recém-Nascido , Minnesota/epidemiologia , Estadiamento de Neoplasias , Neuroblastoma/epidemiologia , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Ontário/epidemiologia , Avaliação de Resultados em Cuidados de Saúde , Prognóstico , Quebeque/epidemiologia , Encaminhamento e Consulta , Ácido Vanilmandélico/urina
11.
Ann Thorac Surg ; 62(1): 246-50, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8678651

RESUMO

BACKGROUND: The purpose of our study was to determine the incidence and locations of M1 disease at presentation in patients with non-small cell lung cancer to help design appropriate preoperative imaging algorithms. METHODS: All patients with non-small cell lung cancer seen between 1991 and 1993 were identified, and records were reviewed. For patients with M1 disease, the sites of distant metastases and the methods of diagnosis were recorded. RESULTS: Of 348 patients identified, 276 (79%) had M0 disease and 72 (21%) had M1 disease. In 40 of 72 patients (56%), M1 disease was detected via chest or abdominal computed tomography (CT). Brain, bone, liver, and adrenal glands were the most common sites of metastatic disease, in decreasing order. Brain metastases often occurred as an isolated finding, although isolated liver metastases were uncommon. CONCLUSIONS: M1 disease was common at presentation, and was often detectable via chest CT. The incremental yield of abdominal CT over chest CT was very small, and therefore abdominal CT is not an effective method of screening for metastases if chest CT has been performed.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/secundário , Neoplasias Pulmonares/patologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/epidemiologia , Adenocarcinoma/secundário , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/epidemiologia , Neoplasias das Glândulas Suprarrenais/secundário , Idoso , Algoritmos , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/epidemiologia , Neoplasias Ósseas/secundário , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/secundário , Feminino , Humanos , Incidência , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/secundário , Masculino , Prevalência , Tomografia Computadorizada por Raios X
12.
Cancer ; 76(11): 2363-71, 1995 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8635044

RESUMO

BACKGROUND: The Quebec Neuroblastoma Screening Project was initiated to assess clinical and biologic aspects of neuroblastomas detected by screening infants born in the province of Quebec from May 1, 1989, to April 30, 1994. METHODS: Infants were screened for preclinical detection of neuroblastoma by determination of catecholamine metabolites, vanillylmandelic acid (VMA), and homovanillic acid (HVA). Patients with tumors discovered through this screening as well as patients in the same birth cohort with clinically detected tumors were referred to Quebec Oncology Centers for further investigation, diagnosis, and treatment. Pathology specimens were submitted to Childrens Hospital Los Angeles for central review. Tumors were histopathologically classified according to the Shimada system. RESULTS: As of August, 1993, 340,000 infants were screened at 3 weeks and 245,000 of them were retested at 6 months of age. Thirty-one tumors were detected through this screening and removed. Histologic material was available for 27 cases: 14 were detected at 3 weeks of age and 13 at 6 months of age. Twenty-six patients had tumors with favorable histology (FH), and one patient had a Stage I tumor with unfavorable histology (UH). At the time of this writing, all mass screening patients are alive, including one child with relapsed disease. During this period, 48 tumors were detected clinically in the same birth cohort, 40 of which were evaluated histologically. Of these 40 cases, 28 of 29 tumors diagnosed in patients up to age 12 months indicated an FH, whereas 9 of 11 tumors diagnosed in patients older than age 12 months indicated a UH. All patients with FH tumors are alive including a child with relapsed disease. The single patient with UH diagnosed before age 12 months died of disease. Of the nine patients with UH diagnosed after age 12 months, four died of disease, one relapsed, and four are alive (including one treated with bone marrow transplantation) after variable follow-up periods. CONCLUSIONS: The tumors detected by mass screening, similar to those tumors detected through clinical examination before age 12 months, were predominantly FH with good prognosis. However, those tumors that were missed by screening and were detected clinically after the patient was 12 months of age were predominantly UH, with serious clinical problems. This subgroup of patients not detectable by the current screening system presents an immediate and important clinical challenge that should be addressed in future studies.


Assuntos
Programas de Rastreamento , Neuroblastoma/prevenção & controle , Fatores Etários , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Seguimentos , Ácido Homovanílico/urina , Humanos , Lactente , Recém-Nascido , Los Angeles , Masculino , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Neuroblastoma/patologia , Neuroblastoma/terapia , Neuroblastoma/urina , América do Norte , Prognóstico , Quebeque , Taxa de Sobrevida , Resultado do Tratamento , Ácido Vanilmandélico/urina
13.
Proc Natl Acad Sci U S A ; 92(10): 4158-63, 1995 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-11607542

RESUMO

Microbial elicitors or attempted infection with an avirulent pathogen strain causes the rapid production of reactive oxygen intermediates. Recent findings indicate that H2O2 from this oxidative burst plays a central role in the orchestration of the hypersensitive response: (i) as the substrate driving the cross-linking of cell wall structural proteins to slow microbial ingress prior to the deployment of transcription-dependent defenses and to trap pathogens in cells destined to undergo hypersensitive cell death, (ii) as a local threshold trigger of this programmed death in challenged cells, and (iii) as a diffusible signal for the induction in adjacent cells of genes encoding cellular protectants such as glutathione S-transferase and glutathione peroxidase. These findings provide the basis for an integrated model for the orchestration of the localized hypersensitive resistance response to attack by an avirulent pathogen.

14.
Plant Cell ; 6(12): 1703-1712, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12244231

RESUMO

Elicitation of soybean cells causes a rapid insolubilization of two cell wall structural proteins, p33 and p100. Likewise, a short elicitation of 30 min rendered cell walls more refractory to enzyme digestion as assayed by the yield of protoplasts released. This effect could be ascribed to protein cross-linking because of its insensitivity to inhibitors of transcription (actinomycin D) and translation (cycloheximide) and its induction by exogenous H2O2. Moreover, the induced loss of protoplasts could be prevented by preincubation with DTT, which also blocks peroxidase-mediated oxidative cross-linking. The operation of protein insolubilization in plant defense was also demonstrated by its occurrence in the incompatible interaction but not in the compatible interaction between soybean and Pseudomonas syringae pv glycinea. Likewise, protein insolubilization was observed in bean during non-host hypersensitive resistance to the tobacco pathogen P. s. pv tabaci mediated by the hypersensitive resistance and pathogenicity (Hrp) gene cluster. Our data strongly suggest that rapid protein insolubilization leads to a strengthened cell wall, and this mechanism functions as a rapid defense in the initial stages of the hypersensitive response prior to deployment of transcription-dependent defenses.

15.
Leukemia ; 8(5): 903-8, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8182949

RESUMO

We studied a patient with juvenile chronic myelogenous leukemia (JCML) whose terminal course was characterized by transformation to acute lymphoblastic leukemia. Karyotypic studies identified monosomy 7 in leukemic myelomonocytic marrow cells during the chronic phase and in the lymphoblasts during the transformation phase. Our ability to sustain the transformed lymphoblasts in culture allowed us to characterize them further. CD19, HLA-DR, and CD10 were present, consistent with a pre-B acute lymphoblastic leukemia phenotype. CD14 (My-4) and CD13 (My-7) were negative. Rearrangement of immunoglobulin heavy- and light-chain genes identified monoclonal populations of cells of the B lineage. This case provides further evidence that JCML is a clonal disease of pluripotent stem-cell origin.


Assuntos
Crise Blástica/patologia , Cromossomos Humanos Par 7 , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Monossomia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Crise Blástica/genética , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Rearranjo Gênico de Cadeia Leve de Linfócito B , Humanos , Imunofenotipagem , Lactente , Cariotipagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética
16.
Blood ; 83(5): 1251-7, 1994 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8118029

RESUMO

Deep vein thrombosis (DVT) and pulmonary embolism (PE) occur in pediatric patients; however, the incidence, associated morbidity, and mortality are unknown. A Canadian registry of DVT and PE in children (ages 1 month to 18 years) was established July 1, 1990 in 15 tertiary-care pediatric centers. One-hundred thirty-seven patients were identified prospectively and are the subject of this report. The incidence of DVT/PE was 5.3/10,000 hospital admissions or 0.07/10,000 children in Canada. Infants under 1 year old and teenagers predominated with equal numbers of both sexes. DVT were located in the upper (n = 50) and lower (n = 79) venous system, or as PE alone (n = 8). Central venous lines (CVLs) were present in approximately 33% of children with DVT (n = 45). Associated conditions were present in 96% of children and 90% of children had two or more associated conditions for DVT. DVT was diagnosed by venography (n = 83), duplex ultrasound (n = 37), and other combinations (n = 17). Twenty-two of the 31 ventilation/perfusion scans performed were interpreted as high-probability scans for PE. Therapy consisted of heparin (n = 115), thrombolysis (n = 15), surgical removal of a CVL or thrombus (n = 22), and oral anticoagulant therapy (n = 103). Significant bleeding complications did not occur. However, three (2.2%) children died as a direct consequence of their thromboembolic disease; DVT reoccurred in 23 children and postphlebitic syndrome (PPS) occurred in 26. In conclusion, DVTs occur in a significant number of hospitalized children with a mortality of 2.2%. Complications are not hemorrhagic, but thrombotic, and characterized by PE, recurrent disease, and PPS. In contrast to adults, the upper venous system is frequently affected because of the use of CVLs. The frequency of DVT/PE justifies controlled trials of primary prophylaxis in high-risk groups, and therapeutic trials to determine optimal treatment.


Assuntos
Embolia Pulmonar/epidemiologia , Tromboembolia/epidemiologia , Tromboflebite/epidemiologia , Administração Oral , Anticoagulantes/administração & dosagem , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Ontário , Embolia Pulmonar/terapia , Recidiva , Tromboembolia/terapia , Tromboflebite/terapia
18.
Cancer Res ; 53(21): 5269-73, 1993 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8221661

RESUMO

Neuroblastoma is a common childhood malignancy of the sympathetic nervous system. Mutations in p53, a tumor suppressor gene located on the short arm of chromosome 17, are one of the most common genetic lesions in human cancers. The evidence for trisomies of 17q with loss of 17p in some cases of neuroblastoma led us to consider whether p53 mutations might contribute to the onset and progression of this malignancy. In this study, primary tumors from 38 neuroblastoma patients were screened for mutations within the coding exons of the p53 gene by single-strand conformation polymorphism analysis, and potential mutations were further analyzed by nucleotide sequence analysis. Previously described sequence variations were detected in many of the tumors, including a silent polymorphism at codon 213 (CGA to CGG) and the nontransforming Pro to Arg substitution at codon 72 (CCC to CGC). However, no other sequence variations were detected within the coding portions of the p53 gene. This finding suggests that p53 mutations do not contribute to the etiology of neuroblastoma and that the chromosome 17 alterations observed in neuroblastoma involve genes which are distinct from the p53 locus.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 17 , Genes p53 , Mutação , Neuroblastoma/genética , Trissomia , Sequência de Bases , Criança , Clonagem Molecular , Códon/genética , Primers do DNA , Éxons , Humanos , Dados de Sequência Molecular , Estadiamento de Neoplasias , Neuroblastoma/patologia , Neuroblastoma/cirurgia , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético
19.
Am J Pediatr Hematol Oncol ; 14(4): 312-9, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1456396

RESUMO

The Quebec Neuroblastoma Screening Project was initiated to assess the clinical and biological aspects of screening infants for the presence of neuroblastoma in North America. All children born in the province of Quebec from May 1, 1989 to April 30, 1994 are eligible for participation. This report provides results from 22 months' accrual of infants who were screened using urine-saturated filter paper for determination of the catecholamine metabolites vanillylmandelic acid (VMA) and homovanillic acid (HVA). More than 157,000 infants have been screened to date at 3 weeks of age, representing 92% of the entire birth population of Quebec. Over 98,000 infants have been screened a second time at 6 months of age, which made up 76% of the Quebec birth cohort. After a two-stage initial screening, 340 (0.13%) infants (182 at 3 weeks and 158 at 6 months) required second laboratory examinations because of elevated levels of urinary VMA, HVA, or both. Twenty infants from the 3-week screening (0.01%) and nine from the 6-month screening (0.01%) were subsequently referred to one of four Quebec pediatric oncology centers for neuroblastoma evaluation. Seven of 20 children from the 3-week screening and two of nine children from the 6-month screening have been identified as having neuroblastoma. During the same period, 14 additional children in the birth cohort were diagnosed clinically with neuroblastoma; eight were diagnosed prior to screening at 3 weeks of age, three children had negative results at 3 weeks of age, two had negative results at 3 weeks and at 6 months of age, and one had never been screened.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Biomarcadores Tumorais/urina , Ácido Homovanílico/urina , Programas de Rastreamento/métodos , Neuroblastoma/diagnóstico , Ácido Vanilmandélico/urina , Algoritmos , Seguimentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactente , Recém-Nascido , Neuroblastoma/urina , Quebeque
20.
J Clin Oncol ; 10(2): 323-9, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1732433

RESUMO

PURPOSE: The purpose of this study was twofold: (1) to provide a population-based estimate of neuroblastoma incidence, disease stage and age distribution, and survival and mortality rates in North America; and (2) to compare these figures in the province of Quebec at a time shortly before the institution of province-wide screening with those in a population-based control group, the Greater Delaware Valley (GDV) Pediatric Tumor Registry. MATERIALS AND METHODS: In Quebec, the four major pediatric teaching hospital records were searched for children with a diagnosis of neuroblastoma. Tumor board registry data and information supplied to the Division of Vital Statistics were also reviewed. Birth statistics were obtained from the population registry. The GDV Pediatric Tumor Registry is a population-based registry of pediatric cancer covering all of Delaware and parts of New Jersey, Pennsylvania, and Maryland. Age, stage of disease, and follow-up data were obtained through December 31, 1989, with Evans neuroblastoma staging data used for all comparisons. RESULTS: One hundred thirty children with neuroblastoma were identified in Quebec and 165 in the GDV, in a combined population of 3,178,736 children. The annual incidence of neuroblastoma was 10.95/10(6) under the age of 15 years and 27.75/10(6) between the ages of 0 and 4 years. The annual mortality rate due to neuroblastoma was 4.89/10(6) and 9.10/10(6) for the age groups 0 to 14 and 0 to 4, respectively. The overall 10-year survival rate for the 295 cases of neuroblastoma was 55%. The 10-year survival rates for patients with Evans stage I-IV and IVS disease were 88%, 90%, 63%, 21%, and 81%. There was no significant difference observed in the incidence, mortality, or survival in the two populations. CONCLUSION: These data represent the first large, population-based description of the clinical presentation and outcome of patients with neuroblastoma in North America, with no significant differences noted between Quebec patients and the GDV patients.


Assuntos
Neuroblastoma/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Masculino , Programas de Rastreamento , Mid-Atlantic Region/epidemiologia , Estadiamento de Neoplasias , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Quebeque/epidemiologia , Sistema de Registros , Taxa de Sobrevida
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