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OBJECTIVES: Identifying therapy-related AML (t-AML) of newly diagnosed acute leukemias is of great interest. Development of t-AML can occur after cytotoxic chemotherapy and/or radiation. We report a case of t-AML with CBFB::MYH11 fusion in a patient with a distant history of treated stage IIIB nodular sclerosing Hodgkin's lymphoma. We present the clinical course of the patient and the methods used to detect and monitor the rearrangement. Core binding factor AML (CBF-AML) after exposure to treatment is considered to be a good prognostic marker. The identification of these favorable AML subtypes such as CBF-AML highlights the importance of identifying genetic alterations, especially with increasing incidences of t-AML due to changes in choice of treatment and prognosis.
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In this study, the fixed-time synchronization (FXTS) of delayed memristive neural networks (MNNs) with hybrid impulsive effects is explored. To investigate the FXTS mechanism, we first propose a novel theorem about the fixed-time stability (FTS) of impulsive dynamical systems, where the coefficients are extended to functions and the derivatives of Lyapunov function (LF) are allowed to be indefinite. After that, we obtain some new sufficient conditions for achieving FXTS of the system within a settling-time using three different controllers. At last, to verify the correctness and effectiveness of our results, a numerical simulation was conducted. Significantly, the impulse strength studied in this paper can take different values at different points, so it can be regarded as a time-varying function, unlike those in previous studies (the impulse strength takes the same value at different points). Hence, the mechanisms in this article are of more practical applicability.
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Redes Neurais de Computação , Fatores de Tempo , Simulação por ComputadorRESUMO
OBJECTIVE: To explore the clinical manifestations, diagnosis, treatment and prognosis of blastic plasmacytoid dendritic cell neoplasm(BPDCN). METHODS: The clinical features, bone marrow morphology and immunophenotyping, treatment and prognosis of 4 patients with BPDCN were analyzed retrospectively. RESULTS: 4 patients had bone marrowï¼ spleen and lymph nodes involvementï¼ 2 patients had skin lesionsï¼ and 3 patients had central nervous system infiltrationï¼ Tailing phenomenon of abnormally cells could be seen in bone marrow. The immunophenotyping showed that CD56, CD4 and CD123 expression was observed in 4 patientsï¼ and CD304 in 3 patientsï¼ One patient refused chemotherapy and died early. Both patients achieved complete remission after the initial treatment with DA+VP regimen, 1 of them achieved complete remission after recurrence by using the same regimen againï¼ One patient failed to respond to reduced dose of DA+VP chemotherapy, and then achieved complete remission with venetoclax+azacitidine. CONCLUSION: The malignant cells in BPDCN patients often infiltrate bone marrow, spleen and lymph nodes, and have specical phenotypes, with poor prognosis. The treatment should take into account both myeloid and lymphatic systems. The treatment containing new drugs such as BCL-2 inhibitors combined with demethylation drugs is worth trying.
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Antineoplásicos , Neoplasias Hematológicas , Transtornos Mieloproliferativos , Neoplasias Cutâneas , Humanos , Células Dendríticas , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Antineoplásicos/uso terapêutico , Medula Óssea/patologia , Neoplasias Hematológicas/tratamento farmacológicoRESUMO
INTRODUCTION: Endogenous testosterone deficiency or excess anabolic-androgenic steroids (AAS) have been linked to alter the physiology of different organs in the body, more specifically, the vasculature of coronary arteries. Despite the health-related concerns of using synthetic testosterone derivatives, such as AAS, there has been a tremendous increase in the use of AAS among athletes and bodybuilders. AREAS COVERED: We have highlighted the three main mechanisms that AAS increase the risk of coronary artery disease (CAD): altering the homeostasis of lipid metabolism which results in dyslipidemia and subsequently atherosclerosis, disturbing the function of platelet which results in platelet aggregation and subsequent thrombosis, and increasing the risk of coronary vasospasm by affecting the physiological function of vascular bed. EXPERT OPINION: Despite the restriction of AAS in specific clinical conditions such as testosterone deficiency and cancer therapy, many amateurs' athletes misuse the AAS. Although there has been a strong association between the AAS misuse and risk of developing CAD, the more valued approach would be a randomized clinical double-blind trial. The suggested primary endpoint would be an occurrence of adverse cardiovascular events, such as myocardial infarction, cerebrovascular accidents, and death. Increasing awareness of the risk of missing AAS among high-risk groups is imperative.
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Anabolizantes , Doença da Artéria Coronariana , Dopagem Esportivo , Anabolizantes/efeitos adversos , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Humanos , Testosterona , Congêneres da Testosterona/efeitos adversosRESUMO
Dercum's disease (DD), also described as adiposis dolorosa, is a poorly understood and rare adipose tissue disorder involving obesity and painful adipose tissue masses. Patients may have associated bruising and constitutional symptoms such as fatigue, difficulty concentrating, and sleep disturbance. DD was initially described in 1888 by Francis Xavier Dercum, and was classified into four subtypes, including generalized diffuse, generalized nodular, localized nodular, and juxta-articular subtypes. While this disease has been described for more than 130 years, its etiology and treatment remain elusive. We describe a case of a patient with DD who presented to Ochsner Medical Center, New Orleans, LA, for evaluation of treatment options. We review current knowledge on this rare disease and data on modern treatment methods.
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Adipose Dolorosa , Tecido Adiposo , Adipose Dolorosa/diagnóstico , Diagnóstico Diferencial , Humanos , Obesidade , DorRESUMO
Lung cancer is currently the leading cause of cancer death in both developing and developed countries. Given that lung cancer has poor prognosis in later stages, it is essential to achieve an early diagnosis to maximize patients' overall survival. Non-small cell lung cancer (NSCLC) is the most common form of primary lung cancer in both smokers and non-smokers. The current standard screening method, low-dose computed tomography (LDCT), is the only radiological method that demonstrates to have mortality benefits across multiple large randomized clinical trials (RCT). However, these RCTs also found LDCT to have a significant false positive rate that results in unnecessary invasive biopsies being performed. Due to the lack of both sensitive and specific screening methods for the early detection of lung cancer, there is an urgent need for alternative minimally or non-invasive biomarkers that may provide diagnostic, and/or prognostic information. This has led to the identification of circulating biomarkers that can be readily detectable in blood and have been extensively studied as prognosis markers. Circulating microRNA (miRNA) in particular has been investigated for these purposes as an augmentation to LDCT, or as direct diagnosis of lung cancer. There is, however, a lack of consensus across the studies on which miRNAs are the most clinically useful. Besides miRNA, other potential circulating biomarkers include circulating tumor cells (CTCs), circulating tumor DNA (ctDNAs) and non-coding RNAs (ncRNAs). In this review, we provide the current outlook of several of these biomarkers for the early diagnosis of NSCLC.
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l-dopa and dopamine D2 receptor (D2R) agonists are commonly used to relieve the motor deficits of Parkinson's disease. However, long-term treatment with l-dopa or D2R agonists can induce adverse effects such as abnormal involuntary movements (AIMs), which are major limiting factors in achieving long-term control of parkinsonian syndromes. The pathophysiological mechanisms involved in the development of dopaminergic agonist-induced adverse effects are not well understood. Here, we examined the role of two D2R isoforms, D2S and D2L, in l-dopa-induced AIMs using dopamine D2L knockout (D2L KO) mice (expressing purely D2S) and wild-type mice (expressing predominantly D2L). We found that D2L KO mice displayed markedly enhanced AIMs in response to chronic treatment of l-dopa compared to wild-type mice. The l-dopa-induced enhancement of AIMs in D2L KO mice was significantly reduced by the D2R antagonist eticlopride. D2L KO mice also displayed markedly enhanced AIMs in response to chronic treatment with quinpirole, a preferential D2R agonist. These results suggest that D2S contributes more than D2L to dopaminergic agonist-induced AIMs. Our findings may uncover a new factor that contributes to the pathophysiology of dopaminergic drug-induced AIMs, a characteristic manifestation of dyskinesia and also present in psychosis. There is a possibility that the increased ratio of D2S to D2L in the brain plays a significant role in the development of AIM side effects induced by l-dopa or D2R agonists. See Video Abstract, http://links.lww.com/WNR/A622.
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Discinesia Induzida por Medicamentos/metabolismo , Levodopa/efeitos adversos , Atividade Motora/efeitos dos fármacos , Isoformas de Proteínas/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Agonistas de Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , Masculino , Camundongos , Camundongos Knockout , Quimpirol/farmacologia , Receptores de Dopamina D2/genética , Salicilamidas/farmacologiaAssuntos
Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/terapia , Emigrantes e Imigrantes/legislação & jurisprudência , Emigração e Imigração/legislação & jurisprudência , Habitação/legislação & jurisprudência , Programas de Rastreamento/métodos , Adolescente , Criança , El Salvador/etnologia , Feminino , Guatemala/etnologia , Honduras/etnologia , Humanos , Masculino , Estados UnidosRESUMO
OBJECTIVE: Interrater agreement evaluation of a tool to document and code the situational factors and mechanisms of knockouts (KOs) and technical knockouts (TKOs) in mixed martial arts (MMA). DESIGN: Retrospective case series. SETTING: Professional MMA matches from the Ultimate Fighting Championship-2006-2012. PARTICIPANTS: Two nonmedically trained independent raters. MAIN OUTCOME MEASURES: The MMA Knockout Tool (MMA-KT) consists of 20 factors and captures and codes information on match characteristics, situational context preceding KOs and TKOs, as well as describing competitor states during these outcomes. The MMA-KT also evaluates the mechanism of action and subsequent events surrounding a KO. RESULTS: The 2 raters coded 125 unique events for a total of 250 events. The 8 factors of Part A had an average κ of 0.87 (SD = 0.10; range = 0.65-0.98); 7 were considered "substantial" agreement and 1 "moderate." Part B consists of 12 factors with an average κ of 0.84 (SD = 0.16; range = 0.59-1.0); 7 classified as "substantial" agreement, 4 "moderate," and 1 "fair." The majority of the factors in the MMA-KT demonstrated substantial interrater agreement, with an average κ of 0.86 (SD = 0.13; range = 0.59-1.0). CONCLUSIONS: The MMA-KT is a reliable tool to extract and code relevant information to investigate the situational factors and mechanism of KOs and TKOs in MMA competitions.
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Concussão Encefálica/diagnóstico , Artes Marciais/lesões , Variações Dependentes do Observador , Inconsciência/diagnóstico , Transtornos da Consciência/diagnóstico , Humanos , Masculino , Estudos RetrospectivosAssuntos
Doença Crônica , Educação Médica/métodos , Medicina nas Artes , Relações Médico-Paciente , Escultura , Humanos , MichiganRESUMO
AMG 386 is an investigational first-in-class peptide-Fc fusion protein (peptibody) that inhibits angiogenesis by preventing the interaction of angiopoietin-1 (Ang1) and Ang2 with their receptor, Tie2. Although the therapeutic value of blocking Ang2 has been shown in several models of tumorigenesis and angiogenesis, the potential benefit of Ang1 antagonism is less clear. To investigate the consequences of Ang1 neutralization, we have developed potent and selective peptibodies that inhibit the interaction between Ang1 and its receptor, Tie2. Although selective Ang1 antagonism has no independent effect in models of angiogenesis-associated diseases (cancer and diabetic retinopathy), it induces ovarian atrophy in normal juvenile rats and inhibits ovarian follicular angiogenesis in a hormone-induced ovulation model. Surprisingly, the activity of Ang1 inhibitors seems to be unmasked in some disease models when combined with Ang2 inhibitors, even in the context of concurrent vascular endothelial growth factor inhibition. Dual inhibition of Ang1 and Ang2 using AMG 386 or a combination of Ang1- and Ang2-selective peptibodies cooperatively suppresses tumor xenograft growth and ovarian follicular angiogenesis; however, Ang1 inhibition fails to augment the suppressive effect of Ang2 inhibition on tumor endothelial cell proliferation, corneal angiogenesis, and oxygen-induced retinal angiogenesis. In no case was Ang1 inhibition shown to (a) confer superior activity to Ang2 inhibition or dual Ang1/2 inhibition or (b) antagonize the efficacy of Ang2 inhibition. These results imply that Ang1 plays a context-dependent role in promoting postnatal angiogenesis and that dual Ang1/2 inhibition is superior to selective Ang2 inhibition for suppression of angiogenesis in some postnatal settings.
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Angiopoietina-1/antagonistas & inibidores , Divisão Celular/efeitos dos fármacos , Neoplasias Experimentais/patologia , Neovascularização Patológica/prevenção & controle , Proteínas Recombinantes de Fusão/farmacologia , Sequência de Aminoácidos , Animais , Córnea/irrigação sanguínea , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Neoplasias Experimentais/irrigação sanguínea , Folículo Ovariano/irrigação sanguínea , Ratos , Ratos Sprague-DawleyRESUMO
RANKL is a TNF family member that mediates osteoclast formation, activation, and survival by activating RANK. The proresorptive effects of RANKL are prevented by binding to its soluble inhibitor osteoprotegerin (OPG). Recombinant human OPG-Fc recognizes RANKL from multiple species and reduced bone resorption and increased bone volume, density, and strength in a number of rodent models of bone disease. The clinical development of OPG-Fc was discontinued in favor of denosumab, a fully human monoclonal antibody that specifically inhibits primate RANKL. Direct binding assays showed that denosumab bound to human RANKL but not to murine RANKL, human TRAIL, or other human TNF family members. Denosumab did not suppress bone resorption in normal mice or rats but did prevent the resorptive response in mice challenged with a human RANKL fragment encoded primarily by the fifth exon of the RANKL gene. To create mice that were responsive to denosumab, knock-in technology was used to replace exon 5 from murine RANKL with its human ortholog. The resulting "huRANKL" mice exclusively express chimeric (human/murine) RANKL that was measurable with a human RANKL assay and that maintained bone resorption at slightly reduced levels versus wildtype controls. In young huRANKL mice, denosumab and OPG-Fc each reduced trabecular osteoclast surfaces by 95% and increased bone density and volume. In adult huRANKL mice, denosumab reduced bone resorption, increased cortical and cancellous bone mass, and improved trabecular microarchitecture. These huRANKL mice have potential utility for characterizing the activity of denosumab in a variety of murine bone disease models.
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Anticorpos Monoclonais/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/fisiopatologia , Técnicas de Introdução de Genes , Ligante RANK/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Afinidade de Anticorpos/efeitos dos fármacos , Especificidade de Anticorpos/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Denosumab , Humanos , Hipercalcemia/tratamento farmacológico , Camundongos , Dados de Sequência Molecular , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoprotegerina/metabolismo , Fenótipo , Ligação Proteica/efeitos dos fármacos , Ligante RANK/química , Ligante RANK/genética , Ligante RANK/farmacocinética , Ligante RANK/farmacologia , Ligante RANK/uso terapêutico , Microtomografia por Raio-XRESUMO
gammadelta T cells uniquely contribute to host immune defense, but how this is accomplished remains unclear. Here, we analyzed the nonclassical major histocompatibility complex class I T10 and T22-specific gammadelta T cells in mice and found that encountering antigen in the thymus was neither required nor inhibitory for their development. But when triggered through the T cell receptor, ligand-naive lymphoid-gammadelta T cells produced IL-17, whereas ligand-experienced cells made IFN-gamma. Immediately after immunization, a large fraction of IL-17(+) gammadelta T cells were found in the draining lymph nodes days before the appearance of antigen-specific IL-17(+) *beta T cells. Thus, thymic selection determines the effector fate of gammadelta T cells rather than constrains their antigen specificities. The swift IL-17 response mounted by antigen-naive gammadelta T cells suggests a critical role for these cells at the onset of an acute inflammatory response to novel antigens.
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Diferenciação Celular/imunologia , Interferon gama/biossíntese , Interleucina-17/biossíntese , Ativação Linfocitária/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Subpopulações de Linfócitos T/citologia , Animais , Antígenos/imunologia , Antígenos de Superfície/imunologia , Encefalomielite Autoimune Experimental/imunologia , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe I/imunologia , Camundongos , Subpopulações de Linfócitos T/imunologia , Timo/citologia , Timo/imunologiaRESUMO
The Fc region has two highly conserved methionine residues, Met 33 (C(H)3 domain) and Met 209 (C(H)3 domain), which are important for the Fc's structure and biological function. To understand the effect of methionine oxidation on the structure and stability of the human IgG1 Fc expressed in Escherichia coli, we have characterized the fully oxidized Fc using biophysical (DSC, CD, and NMR) and bioanalytical (SEC and RP-HPLC-MS) methods. Methionine oxidation resulted in a detectable secondary and tertiary structural alteration measured by circular dichroism. This is further supported by the NMR data. The HSQC spectral changes indicate the structures of both C(H)2 and C(H)3 domains are affected by methionine oxidation. The melting temperature (Tm) of the C(H)2 domain of the human IgG1 Fc was significantly reduced upon methionine oxidation, while the melting temperature of the C(H)3 domain was only affected slightly. The change in the C(H)2 domain T m depended on the extent of oxidation of both Met 33 and Met 209. This was confirmed by DSC analysis of methionine-oxidized samples of two site specific methionine mutants. When incubated at 45 degrees C, the oxidized Fc exhibited an increased aggregation rate. In addition, the oxidized Fc displayed an increased deamidation (at pH 7.4) rate at the Asn 67 and Asn 96 sites, both located on the C(H)2 domain, while the deamidation rates of the other residues were not affected. The methionine oxidation resulted in changes in the structure and stability of the Fc, which are primarily localized to the C(H)2 domain. These changes can impact the Fc's physical and covalent stability and potentially its biological functions; therefore, it is critical to monitor and control methionine oxidation during manufacturing and storage of protein therapeutics.
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Fragmentos Fc das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/química , Imunoglobulina G/imunologia , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/isolamento & purificação , Imunoglobulina G/genética , Cinética , Metionina/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Mutação/genética , Ressonância Magnética Nuclear Biomolecular , Oxirredução , Desnaturação Proteica , Estrutura Terciária de Proteína , TemperaturaRESUMO
Here we report the NMR resonance assignments for the Fc region of human IgG1 expressed in E. coli, a 51.4 kDa dimer in solution (residues 221-447). The assignments have been deposited in the BioMagResBank with a BMRB accession number of 15514.
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Proteínas de Transporte/química , Fragmentos Fc das Imunoglobulinas/química , Espectroscopia de Ressonância Magnética/métodos , Sequência de Aminoácidos , Isótopos de Carbono/química , Humanos , Peso Molecular , Isótopos de Nitrogênio/química , Estrutura Terciária de Proteína , PrótonsRESUMO
Keratinocyte growth factor receptor (KGFR) and fibroblast growth factor receptor (FGFR) 2c share identical amino acid sequences, except for a 46-amino acid domain in the extracellular region. Monoclonal antibodies (MAbs) specific to KGFR have not been reported nor are commercially available. In this study, we generated murine MAbs specific to KGFR in non-obese diabetic (NOD) mice using a modified Repeated Immunizations at Multiple Sites (RIMMS) technology. Stable cell lines expressing the full-length human KGFR or FGFR2c were produced to facilitate the identification of KGFR-specific MAbs. Following the initial screening of hybridoma clones with a fluorescence-based, confocal cell detection method and ELISA, KGFR-specific MAbs were selected and confirmed by flow cytometry and Western blot analyses. Antagonistic MAbs were identified using a cell-based functional assay. These KGFR MAbs will be important reagents for studying the biological function and tissue distribution of this receptor in normal and pathological conditions.
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Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/química , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/imunologia , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos , Western Blotting , Células CHO , Linhagem Celular , Cricetinae , Cricetulus , Citometria de Fluxo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Dados de Sequência MolecularRESUMO
c-Met is a well-characterized receptor tyrosine kinase for hepatocyte growth factor (HGF). Compelling evidence from studies in human tumors and both cellular and animal tumor models indicates that signaling through the HGF/c-Met pathway mediates a plethora of normal cellular activities, including proliferation, survival, migration, and invasion, that are at the root of cancer cell dysregulation, tumorigenesis, and tumor metastasis. Inhibiting HGF-mediated signaling may provide a novel therapeutic approach for treating patients with a broad spectrum of human tumors. Toward this goal, we generated and characterized five different fully human monoclonal antibodies that bound to and neutralized human HGF. Antibodies with subnanomolar affinities for HGF blocked binding of human HGF to c-Met and inhibited HGF-mediated c-Met phosphorylation, cell proliferation, survival, and invasion. Using a series of human-mouse chimeric HGF proteins, we showed that the neutralizing antibodies bind to a unique epitope in the beta-chain of human HGF. Importantly, these antibodies inhibited HGF-dependent autocrine-driven tumor growth and caused significant regression of established U-87 MG tumor xenografts. Treatment with anti-HGF antibody rapidly inhibited tumor cell proliferation and significantly increased the proportion of apoptotic U-87 MG tumor cells in vivo. These results suggest that an antibody to an epitope in the beta-chain of HGF has potential as a novel therapeutic agent for treating patients with HGF-dependent tumors.
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Anticorpos Monoclonais/farmacologia , Glioblastoma/terapia , Fator de Crescimento de Hepatócito/imunologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/imunologia , Linhagem Celular Tumoral , Epitopos/imunologia , Feminino , Glioblastoma/imunologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Fator de Crescimento de Hepatócito/antagonistas & inibidores , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Imunoglobulina G/biossíntese , Imunoglobulina G/química , Imunoglobulina G/imunologia , Camundongos , Camundongos Nus , Fosforilação , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The hematopoietic stem cell line, Myl-D7, is maintained by a self-renewing stem cell population that spontaneously generates myeloid, lymphoid, and erythroid progeny. MS-5 stromal cells are necessary for the growth of Myl-D7 cells. One component of the Myl-D7 cells proliferation activity released by MS-5 stromal cells was enriched by Q sepharose fractionation and shown to be colony stimulating factor-1 (CSF-1) by Western blotting, BAC1.2F5 cell bioassay and inhibition of Myl-D7 proliferation by CSF-1 antibody. The requirement of Myl-D7 cells for CSF-1 was also demonstrated independently by selecting for rare, stroma-independent Myl-D7 mutant clones able to grow without stroma and additional factors. Eighty-nine stroma-independent mutant clones were obtained and belonged to two classes. The majority of mutants did not secrete any growth promoting activity. The second, rarer class of mutants releases a factor that stimulates proliferation/survival for up to several months and approximately half of the secretors express high levels of CSF-1 mRNA. Wild type Myl-D7 grown with supernatants from the secretor cells retained the stem cell phenotype. These data suggest that CSF-1 may act as a key factor in stroma-regulated hematopoiesis and cell-cell interaction.
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Linhagem Celular , Células Clonais/metabolismo , Meios de Cultivo Condicionados/metabolismo , Células-Tronco Hematopoéticas , Fator Estimulador de Colônias de Macrófagos/fisiologia , Animais , Fracionamento Celular , Proliferação de Células , Meios de Cultivo Condicionados/química , Substâncias de Crescimento/metabolismo , Substâncias de Crescimento/fisiologia , Camundongos , Células EstromaisRESUMO
Angiopoietin-2 (Ang2) exhibits broad expression in the remodeling vasculature of human tumors but very limited expression in normal tissues, making it an attractive candidate target for antiangiogenic cancer therapy. To investigate the functional consequences of blocking Ang2 activity, we generated antibodies and peptide-Fc fusion proteins that potently and selectively neutralize the interaction between Ang2 and its receptor, Tie2. Systemic treatment of tumor-bearing mice with these Ang2-blocking agents resulted in tumor stasis, followed by elimination of all measurable tumor in a subset of animals. These effects were accompanied by reduced endothelial cell proliferation, consistent with an antiangiogenic therapeutic mechanism. Anti-Ang2 therapy also prevented VEGF-stimulated neovascularization in a rat corneal model of angiogenesis. These results imply that specific Ang2 inhibition may represent an effective antiangiogenic strategy for treating patients with solid tumors.