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1.
Acta Naturae ; 16(1): 101-110, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38698957

RESUMO

Monoclonal antibodies and recombinant antibody fragments are a very promising therapeutic tool to combat infectious diseases. Due to their unique paratope structure, nanobodies (VHHs) hold several advantages over conventional monoclonal antibodies, especially in relation to viral infections. Influenza A viruses (IAVs) remain a major threat to public health. The hemagglutinin (HA) protein is the main protective and immunodominant antigen of IAVs. In this study, three broadly reactive nanobodies (D9.2, E12.2, and D4.2) to H3N2 influenza strains were isolated and Fc-fusion proteins (VHH-Fcs) were obtained and characterized in vitro. This modification improved the nanobodies' binding activity and allowed for their interaction with a wider range of strains. The D9.2-Fc antibody showed a 100% protection rate against mortality in vivo in a mouse lethal model. Furthermore, we demonstrated that the observed protection has to do with Fc-FcγR interactions. These results indicate that D9.2-Fc can serve as an effective antiviral agent against the H3N2 influenza infection.

2.
Subst Abuse ; 14: 1178221820955185, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32963470

RESUMO

BACKGROUND: Shared etiological pathways of dopamine and serotonin neurotransmission play a central role in heavy alcohol intake and exacerbation in the symptoms of depression.We investigated the treatment efficacy of Quetiapine fumarate extended release (XR) in lowering alcohol intake in alcohol use disorder (AUD) patients indicated by the shared alleviation of depression ratings and patterns of heavy drinking. METHODS: Hundred and eight male and female heavy drinking AUD patients in the age range of 18 to 64 years. participated in a randomized clinical trial (RCT) to receive 12 weeks of quetiapine XR or placebo (N = 115). Participants were sub-grouped by the severity grading of depression using Montgomery-Asberg Depression Rating Scale (MADRS) (clinically relevant ⩾8 [CR], clinically non-relevant ⩽7 [CNR]) at baseline in both the groups. Drinking history and depression ratings were assessed at the patients' visits. RESULTS: Heavy drinking days (HDD) and total drinks (TD) were significantly fewer in CR patients at the treatment end. A true positive response in AUROC analysis supported the lowering of TD in CR patients. The number of drinking days (NDD) and average drinks per drinking day (AvgD) were lower in the CNR patients at treatment-end. Significant associations with increasing effect sizes were observed for all the heavy drinking measures (HDD, TD, NDD, and AvgD) and MADRS scores by the end of the treatment course. CONCLUSIONS: Baseline elevated depressive symptoms could likely predict the course of heavy alcohol drinking during the treatment, and efficacy outcome of a treatment. AUD patients with baseline clinically significant depression had a progressive lowering in heavy drinking markers significantly corresponding to the lowering of depression symptoms by the end of treatment with Quetiapine fumarate XR.ClinicalTrials.gov: NCT#0049862 (https://clinicaltrials.gov/ct2/show/NCT00498628?term=litten&draw=2&rank=3).

3.
Mol Cancer Ther ; 18(9): 1565-1576, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31270152

RESUMO

Amplification of the epidermal growth factor receptor gene (EGFR) represents one of the most commonly observed genetic lesions in glioblastoma (GBM); however, therapies targeting this signaling pathway have failed clinically. Here, using human tumors, primary patient-derived xenografts (PDX), and a murine model for GBM, we demonstrate that EGFR inhibition leads to increased invasion of tumor cells. Further, EGFR inhibitor-treated GBM demonstrates altered oxidative stress, with increased lipid peroxidation, and generation of toxic lipid peroxidation products. A tumor cell subpopulation with elevated aldehyde dehydrogenase (ALDH) levels was determined to comprise a significant proportion of the invasive cells observed in EGFR inhibitor-treated GBM. Our analysis of the ALDH1A1 protein in newly diagnosed GBM revealed detectable ALDH1A1 expression in 69% (35/51) of the cases, but in relatively low percentages of tumor cells. Analysis of paired human GBM before and after EGFR inhibitor therapy showed an increase in ALDH1A1 expression in EGFR-amplified tumors (P < 0.05, n = 13 tumor pairs), and in murine GBM ALDH1A1-high clones were more resistant to EGFR inhibition than ALDH1A1-low clones. Our data identify ALDH levels as a biomarker of GBM cells with high invasive potential, altered oxidative stress, and resistance to EGFR inhibition, and reveal a therapeutic target whose inhibition should limit GBM invasion.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Família Aldeído Desidrogenase 1/metabolismo , Animais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dasatinibe/farmacologia , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Cloridrato de Erlotinib/farmacologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Retinal Desidrogenase/metabolismo
4.
Nat Cell Biol ; 20(10): 1203-1214, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30202050

RESUMO

Glioblastoma multiforme (GBMs) are recurrent lethal brain tumours. Recurrent GBMs often exhibit mesenchymal, stem-like phenotypes that could explain their resistance to therapy. Analyses revealed that recurrent GBMs have increased tension and express high levels of glycoproteins that increase the bulkiness of the glycocalyx. Studies showed that a bulky glycocalyx potentiates integrin mechanosignalling and tissue tension and promotes a mesenchymal, stem-like phenotype in GBMs. Gain- and loss-of-function studies implicated integrin mechanosignalling as an inducer of GBM growth, survival, invasion and treatment resistance, and a mesenchymal, stem-like phenotype. Mesenchymal-like GBMs were highly contractile and expressed elevated levels of glycoproteins that expanded their glycocalyx, and they were surrounded by a stiff extracellular matrix that potentiated integrin mechanosignalling. Our findings suggest that there is a dynamic and reciprocal link between integrin mechanosignalling and a bulky glycocalyx, implying a causal link towards a mesenchymal, stem-like phenotype in GBMs. Strategies to ameliorate GBM tissue tension offer a therapeutic approach to reduce mortality due to GBM.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Glicocálix/metabolismo , Integrinas/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Sobrevivência Celular/efeitos dos fármacos , Retroalimentação Fisiológica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos Nus , Células-Tronco Neoplásicas/efeitos dos fármacos , Tensão Superficial , Temozolomida/uso terapêutico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Adv Aging Res ; 6(1): 1-10, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28018770

RESUMO

Growth of older population in United States (US) raises concerns for evaluation of health indices that could sustain their workability. This study aimed to characterize the association of health practices used by older working population and measures of quality and duration of their work. Forty (40) non-treatment seeking healthy working individuals residing within United States within 22 - 75 years of age were included in this study. Data were collected from the Customized Employee Biographical Questionnaire (EBQ) and Occupational Health Surveillance Questionnaire (OHRQ) by age groups as 22 - 31, 32 - 41, 42 - 51, 52 - 61 and 62+ and statistically analyzed. Length of working (LOW) showed close association with the duration of physical exercise (DPE) at adjusted R2 = 0.295 and type of work (TOW) at adjusted R2 = 0.598; and Education in the 62+ (oldest) age group. However such relationship was not observed in the 52 - 61 years age group even when DPE and Education were not significantly different from the 62+ group. In the 42 - 51 age group, significant correlation of LOW with DPE and TOW was found. Duration of physical activity could be an important factor associated with the duration of work in the oldest group. Type of work could be significant modifier in determining the length of working in older age-groups. Predecessor elderly groups might need to incorporate some of the measures that were significant in the oldest group, to improve their expectations to work longer. Larger studies could identify and capture various other measures that could be important both for the regional and national US perspective.

6.
Zoonoses Public Health ; 61(8): 560-70, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24673934

RESUMO

This article describes and contrasts the public health response to two human rabies cases: one organ recipient diagnosed within days of symptom onset and the transplant donor who was diagnosed 18 months post-symptom onset. In response to an organ-transplant-related rabies case diagnosed in 2013, organ donor and recipient investigations were conducted by multiple public health agencies. Persons with potential exposure to infectious patient materials were assessed for rabies virus exposure. An exposure investigation was conducted to determine the source of the organ donor's infection. Over 100 persons from more than 20 agencies spent over 2700 h conducting contact investigations in healthcare, military and community settings. The 564 persons assessed include 417 healthcare workers [5.8% recommended for post-exposure prophylaxis (PEP)], 96 community contacts (15.6% recommended for PEP), 30 autopsy personnel (50% recommended for PEP), and 21 other persons (4.8% recommended for PEP). Donor contacts represented 188 assessed with 20.2% recommended for PEP, compared with 5.6% of 306 recipient contacts recommended for PEP. Human rabies cases result in substantial use of public health and medical resources, especially when diagnosis is delayed. Although rare, clinicians should consider rabies in cases of encephalitis of unexplained aetiology, particularly for cases that may result in organ donation.


Assuntos
Busca de Comunicante , Transplante de Órgãos/efeitos adversos , Saúde Pública , Vírus da Raiva/isolamento & purificação , Raiva/transmissão , Doadores de Tecidos , Infecção Hospitalar/virologia , Humanos , Profilaxia Pós-Exposição , Raiva/virologia , Medição de Risco
7.
CNS Oncol ; 2(1): 49-65, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23750318

RESUMO

Angiogenesis inhibitors targeting the VEGF signaling pathway have been US FDA approved for various cancers including glioblastoma (GBM), one of the most lethal and angiogenic tumors. This has led to the routine use of the anti-VEGF antibody bevacizumab in recurrent GBM, conveying substantial improvements in radiographic response, progression-free survival and quality of life. Despite these encouraging beneficial effects, patients inevitably develop resistance and frequently fail to demonstrate significantly better overall survival. Unlike chemotherapies, to which tumors exhibit resistance due to genetic mutation of drug targets, emerging evidence suggests that tumors bypass antiangiogenic therapy while VEGF signaling remains inhibited through a variety of mechanisms that are just beginning to be recognized. Because of the indirect nature of resistance to VEGF inhibitors there is promise that strategies combining angiogenesis inhibitors with drugs targeting such evasive resistance pathways will lead to more durable antiangiogenic efficacy and improved patient outcomes. Further identifying and understanding of evasive resistance mechanisms and their clinical importance in GBM relapse is therefore a timely and critical issue.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Humanos , Transdução de Sinais/efeitos dos fármacos
8.
Khirurgiia (Mosk) ; (5): 31-5, 2013.
Artigo em Russo | MEDLINE | ID: mdl-23715419

RESUMO

The retrospective analysis (2006-2010 yy) of treatment of 895 patients with gastroduodenal ulcer bleeding was conducted. Lethal outcome was registered in 220 (24.6%) patients, of them directly of the ulcer bleeding died 45 (5%). The Rockall score was used as universal prognostic instrument. Of 164 lethal outcomes, did not directly connected to the ulcer bleeding, the etiological distribution was as follows: multiple organ failure - 36% (n=59), cardiovascular diseases - 24.4% (n=40), inveterate oncology - 15.9% (26). Of 45 deaths from bleeding, only 4 patients died of the uncontrolled bleeding, whereas 18 (45%) died after the emergency surgery. Signs of hemorrhagic shock were registered in 60% of died patients (in comparison with 18% among the survived). Bleeding reccurrence was registered in 28.6% of died patients (in comparison with 11% among the survived). The use of the Rockall score confirmed its prognostic value: the mean score was 4.3±2.12 points among the survived patients, whereas among the died patients it was 7.16±2.35 points (p=0.001). Authors conclude, that the leading reasons of death, considering the bleeding itself, were the hemorrhagic shock and recurrent bleeding. Though, about 80% of patients are dying of reasons, do not directly connected to the bleeding episode, but of concomitant diseases (multiple organ failure, cardiovascular and oncologic diseases). The least, nevertheless, leads to the wrong formulation of the final diagnosis and incorrect interpretation of the etiology of death.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Úlcera Péptica Hemorrágica , Úlcera Péptica/complicações , Complicações Pós-Operatórias/mortalidade , Adulto , Idoso , Comorbidade , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Moscou/epidemiologia , Úlcera Péptica Hemorrágica/etiologia , Úlcera Péptica Hemorrágica/mortalidade , Complicações Pós-Operatórias/classificação , Prognóstico , Recidiva , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento
9.
Cancer Cell ; 22(1): 21-35, 2012 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-22789536

RESUMO

Inhibition of VEGF signaling leads to a proinvasive phenotype in mouse models of glioblastoma multiforme (GBM) and in a subset of GBM patients treated with bevacizumab. Here, we demonstrate that vascular endothelial growth factor (VEGF) directly and negatively regulates tumor cell invasion through enhanced recruitment of the protein tyrosine phosphatase 1B (PTP1B) to a MET/VEGFR2 heterocomplex, thereby suppressing HGF-dependent MET phosphorylation and tumor cell migration. Consequently, VEGF blockade restores and increases MET activity in GBM cells in a hypoxia-independent manner, while inducing a program reminiscent of epithelial-to-mesenchymal transition highlighted by a T-cadherin to N-cadherin switch and enhanced mesenchymal features. Inhibition of MET in GBM mouse models blocks mesenchymal transition and invasion provoked by VEGF ablation, resulting in substantial survival benefit.


Assuntos
Neoplasias Encefálicas/patologia , Transição Epitelial-Mesenquimal/fisiologia , Glioblastoma/patologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Fator A de Crescimento do Endotélio Vascular/fisiologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Bevacizumab , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Fosforilação , Proteínas Proto-Oncogênicas c-met/genética , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Cancer Res ; 69(17): 6889-98, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19690143

RESUMO

Activating epidermal growth factor receptor (EGFR) mutations are common in many cancers including glioblastoma. However, clinical responses to EGFR inhibitors are infrequent and short-lived. We show that the Src family kinases (SFK) Fyn and Src are effectors of oncogenic EGFR signaling, enhancing invasion and tumor cell survival in vivo. Expression of a constitutively active EGFR mutant, EGFRvIII, resulted in activating phosphorylation and physical association with Src and Fyn, promoting tumor growth and motility. Gene silencing of Fyn and Src limited EGFR- and EGFRvIII-dependent tumor cell motility. The SFK inhibitor dasatinib inhibited invasion, promoted tumor regression, and induced apoptosis in vivo, significantly prolonging survival of an orthotopic glioblastoma model expressing endogenous EGFRvIII. Dasatinib enhanced the efficacy of an anti-EGFR monoclonal antibody (mAb 806) in vivo, further limiting tumor growth and extending survival. Examination of a large cohort of clinical samples showed frequent coactivation of EGFR and SFKs in glioblastoma patients. These results establish a mechanism linking EGFR signaling with Fyn and Src activation to promote tumor progression and invasion in vivo and provide rationale for combined anti-EGFR and anti-SFK targeted therapies.


Assuntos
Neoplasias do Sistema Nervoso Central/metabolismo , Receptores ErbB/metabolismo , Glioblastoma/metabolismo , Proteínas Proto-Oncogênicas c-fyn/metabolismo , Transdução de Sinais , Quinases da Família src/metabolismo , Animais , Anticorpos Monoclonais/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Sistema Nervoso Central/patologia , Dasatinibe , Sinergismo Farmacológico , Ativação Enzimática , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Inativação Gênica , Glioblastoma/patologia , Humanos , Camundongos , Mutação , Invasividade Neoplásica , Transplante de Neoplasias , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Tiazóis/farmacologia
11.
Eksp Klin Gastroenterol ; (8): 72-8, 2009.
Artigo em Russo | MEDLINE | ID: mdl-20469683

RESUMO

At the present stage the number of operations is reduced at a ulcer gastroenteric bleeding. Occurrence modern antysecretor drags and wide introduction endoscopic and endovascular methods of hemostasis has led to decrease of urgent operative interventions in group of patients with high risk of rebleeding in 4 times. The number of such minimal operations was reduced in 10 times. They do not give expected hemostasis effect and are accompanied high mortality. Change of surgical tactics at elderly patients has led to decrease postoperative mortality from 15.8 up to 5.8% and the general mortality from 15.8 up to 9.6%.


Assuntos
Endoscopia Gastrointestinal/métodos , Úlcera Péptica Hemorrágica/cirurgia , Fatores Etários , Idoso , Humanos , Pessoa de Meia-Idade , Úlcera Péptica Hemorrágica/diagnóstico , Úlcera Péptica Hemorrágica/tratamento farmacológico , Úlcera Péptica Hemorrágica/mortalidade , Complicações Pós-Operatórias/mortalidade , Fatores de Risco , Prevenção Secundária , Índice de Gravidade de Doença , Resultado do Tratamento
12.
Cancer Res ; 68(24): 10034-9, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19074867

RESUMO

In this study, we investigated the precursor and active forms of a p53 small-molecule inhibitor for their effects on temozolomide (TMZ) antitumor activity against glioblastoma (GBM), using both in vitro and in vivo experimental approaches. Results from in vitro cell viability analysis showed that the cytotoxic activity of TMZ was substantially increased when p53 wild-type (p53(wt)) GBMs were cotreated with the active form of p53 inhibitor, and this heightened cytotoxic response was accompanied by increased poly(ADP-ribose) polymerase cleavage as well as elevated cellular phospho-H2AX. Analysis of the same series of GBMs, as intracranial xenografts in athymic mice, and administering corresponding p53 inhibitor precursor, which is converted to the active compound in vivo, yielded results consistent with the in vitro analyses: TMZ + p53 inhibitor precursor cotreatment of three distinct p53(wt) GBM xenografts resulted in significant enhancement of TMZ antitumor effect relative to treatment with TMZ alone, as indicated by serial bioluminescence monitoring as well as survival analysis (P < 0.001 for cotreatment survival benefit in each case). Mice receiving intracranial injection with p53(null) GBM showed similar survival benefit from TMZ treatment regardless of the presence or absence of p53 inhibitor precursor. In total, our results indicate that the p53 active and precursor inhibitor pair enhances TMZ cytotoxicity in vitro and in vivo, respectively, and do so in a p53-dependent manner.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , Proteína Supressora de Tumor p53/antagonistas & inibidores , Animais , Benzotiazóis , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Dacarbazina/administração & dosagem , Dacarbazina/farmacologia , Sinergismo Farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Camundongos , Poli(ADP-Ribose) Polimerases/metabolismo , Temozolomida , Tolueno/análogos & derivados , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Cancer Cell ; 13(3): 206-20, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18328425

RESUMO

Development of hypoxic regions is an indicator of poor prognosis in many tumors. Here, we demonstrate that HIF1alpha, the direct effector of hypoxia, partly through increases in SDF1alpha, induces recruitment of bone marrow-derived CD45+ myeloid cells containing Tie2+, VEGFR1+, CD11b+, and F4/80+ subpopulations, as well as endothelial and pericyte progenitor cells to promote neovascularization in glioblastoma. MMP-9 activity of bone marrow-derived CD45+ cells is essential and sufficient to initiate angiogenesis by increasing VEGF bioavailability. In the absence of HIF1alpha, SDF1alpha levels decrease, and fewer BM-derived cells are recruited to the tumors, decreasing MMP-9 and mobilization of VEGF. VEGF also directly regulates tumor cell invasiveness. When VEGF activity is impaired, tumor cells invade deep into the brain in the perivascular compartment.


Assuntos
Células da Medula Óssea/enzimologia , Neoplasias Encefálicas/irrigação sanguínea , Glioblastoma/irrigação sanguínea , Glioblastoma/enzimologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neovascularização Patológica/enzimologia , Animais , Antígenos de Diferenciação/metabolismo , Benzilaminas , Células da Medula Óssea/imunologia , Transplante de Medula Óssea , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologia , Hipóxia Celular , Linhagem Celular , Movimento Celular , Quimiocina CXCL12/metabolismo , Ciclamos , Células Endoteliais/enzimologia , Glioblastoma/patologia , Compostos Heterocíclicos/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/deficiência , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Antígenos Comuns de Leucócito/metabolismo , Metaloproteinase 9 da Matriz/deficiência , Metaloproteinase 9 da Matriz/genética , Camundongos , Camundongos Knockout , Monócitos/enzimologia , Invasividade Neoplásica , Neovascularização Patológica/patologia , Pericitos/enzimologia , Receptor TIE-2/metabolismo , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/metabolismo , Transdução de Sinais , Transdução Genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
15.
Eur J Clin Microbiol Infect Dis ; 26(4): 271-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17333081

RESUMO

The study presented here was performed in order to create a rule that identifies subjects at high risk for invasive candidiasis in the intensive care setting. Retrospective review and statistical modelling were carried out on 2,890 patients who stayed at least 4 days in nine hospitals in the USA and Brazil; the overall incidence of invasive candidiasis in this group was 3% (88 cases). The best performing rule was as follows: Any systemic antibiotic (days 1-3) OR presence of a central venous catheter (days 1-3) AND at least TWO of the following-total parenteral nutrition (days 1-3), any dialysis (days 1-3), any major surgery (days -7-0), pancreatitis (days -7-0), any use of steroids (days -7-3), or use of other immunosuppressive agents (days -7-0). The rate of invasive candidiasis among patients meeting the rule was 9.9%, capturing 34% of cases in the units, with the following performance: relative risk 4.36, sensitivity 0.34, specificity 0.90, positive predictive value 0.01, and negative predictive value 0.97. The rule may identify patients at high risk of invasive candidiasis.


Assuntos
Candidíase/epidemiologia , Infecção Hospitalar/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Candidíase/diagnóstico , Candidíase/microbiologia , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/microbiologia , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade , Estados Unidos/epidemiologia
16.
Cancer Res ; 66(16): 7864-9, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16912159

RESUMO

The epidermal growth factor receptor (EGFR) is commonly amplified, overexpressed, and mutated in glioblastoma, making it a compelling molecular target for therapy. We have recently shown that coexpression of EGFRvIII and PTEN protein by glioblastoma cells is strongly associated with clinical response to EGFR kinase inhibitor therapy. PTEN loss, by dissociating inhibition of the EGFR from downstream phosphatidylinositol 3-kinase (PI3K) pathway inhibition, seems to act as a resistance factor. Because 40% to 50% of glioblastomas are PTEN deficient, a critical challenge is to identify strategies that promote responsiveness to EGFR kinase inhibitors in patients whose tumors lack PTEN. Here, we show that the mammalian target of rapamycin (mTOR) inhibitor rapamycin enhances the sensitivity of PTEN-deficient tumor cells to the EGFR kinase inhibitor erlotinib. In two isogenic model systems (U87MG glioblastoma cells expressing EGFR, EGFRvIII, and PTEN in relevant combinations, and SF295 glioblastoma cells in which PTEN protein expression has been stably restored), we show that combined EGFR/mTOR kinase inhibition inhibits tumor cell growth and has an additive effect on inhibiting downstream PI3K pathway signaling. We also show that combination therapy provides added benefit in promoting cell death in PTEN-deficient tumor cells. These studies provide strong rationale for combined mTOR/EGFR kinase inhibitor therapy in glioblastoma patients, particularly those with PTEN-deficient tumors.


Assuntos
Receptores ErbB/genética , Glioblastoma/patologia , PTEN Fosfo-Hidrolase/deficiência , PTEN Fosfo-Hidrolase/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/fisiologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ativação Enzimática , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Glioblastoma/genética , Humanos , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Quinazolinas/farmacologia , Sirolimo/farmacologia , Serina-Treonina Quinases TOR , Transfecção
17.
N Engl J Med ; 353(19): 2012-24, 2005 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-16282176

RESUMO

BACKGROUND: The epidermal growth factor receptor (EGFR) is frequently amplified, overexpressed, or mutated in glioblastomas, but only 10 to 20 percent of patients have a response to EGFR kinase inhibitors. The mechanism of responsiveness of glioblastomas to these inhibitors is unknown. METHODS: We sequenced kinase domains in the EGFR and human EGFR type 2 (Her2/neu) genes and analyzed the expression of EGFR, EGFR deletion mutant variant III (EGFRvIII), and the tumor-suppressor protein PTEN in recurrent malignant gliomas from patients who had received EGFR kinase inhibitors. We determined the molecular correlates of clinical response, validated them in an independent data set, and identified effects of the molecular abnormalities in vitro. RESULTS: Of 49 patients with recurrent malignant glioma who were treated with EGFR kinase inhibitors, 9 had tumor shrinkage of at least 25 percent. Pretreatment tissue was available for molecular analysis from 26 patients, 7 of whom had had a response and 19 of whom had rapid progression during therapy. No mutations in EGFR or Her2/neu kinase domains were detected in the tumors. Coexpression of EGFRvIII and PTEN was significantly associated with a clinical response (P<0.001; odds ratio, 51; 95 percent confidence interval, 4 to 669). These findings were validated in 33 patients who received similar treatment for glioblastoma at a different institution (P=0.001; odds ratio, 40; 95 percent confidence interval, 3 to 468). In vitro, coexpression of EGFRvIII and PTEN sensitized glioblastoma cells to erlotinib. CONCLUSIONS: Coexpression of EGFRvIII and PTEN by glioblastoma cells is associated with responsiveness to EGFR kinase inhibitors.


Assuntos
Receptores ErbB/genética , Glioblastoma/genética , PTEN Fosfo-Hidrolase/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Adulto , Idoso , Antineoplásicos/uso terapêutico , DNA de Neoplasias/análise , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Feminino , Gefitinibe , Amplificação de Genes , Deleção de Genes , Expressão Gênica , Genes erbB-1 , Genes erbB-2 , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Oligodendroglioma/tratamento farmacológico , Oligodendroglioma/genética , Oligodendroglioma/metabolismo , PTEN Fosfo-Hidrolase/genética , Reação em Cadeia da Polimerase , Quinazolinas/uso terapêutico , Análise de Sequência de DNA , Transdução de Sinais
18.
J Biol Chem ; 280(29): 26953-64, 2005 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-15908427

RESUMO

Glioblastoma is the most common malignant brain tumor of adults and one of the most lethal cancers. The secreted growth factor pleiotrophin (PTN) promotes glioblastoma migration and proliferation, initiating its oncogenic activities through two cell surface receptors, the protein tyrosine phosphatase receptor zeta (PTPRZ1) and the anaplastic lymphoma kinase (ALK), respectively. Here, we report on the presence and purification of two naturally occurring forms of PTN (18 and 15 kDa) that differentially promote glioblastoma migration and proliferation. Using a panel of glioblastoma cell lines, including low passage patient-derived cultures, we demonstrate that PTN15 promotes glioblastoma proliferation in an ALK-dependent fashion, whereas immobilized PTN18 promotes haptotactic migration of glioblastoma cells in a PTPRZ1-dependent fashion. Mass spectrometric analysis indicated that PTN15 differs from PTN18 by processing of 12 C-terminal amino acids. To demonstrate clinical relevance, we show that PTN15, PTN18, and PTPRZ1 are significantly overexpressed in glioblastoma relative to normal brain at both mRNA and protein levels using microarray, Western blot, and tissue microarray analyses on human tumors. These results indicate that the PTN18-PTPRZ1 and the PTN15-ALK signaling pathways represent potentially important therapeutic targets for glioblastoma invasion and growth.


Assuntos
Proteínas de Transporte/fisiologia , Citocinas/fisiologia , Glioblastoma/patologia , Adulto , Quinase do Linfoma Anaplásico , Proteínas de Transporte/análise , Proteínas de Transporte/metabolismo , Movimento Celular , Proliferação de Células , Citocinas/análise , Citocinas/metabolismo , Glioblastoma/química , Humanos , Invasividade Neoplásica/patologia , Proteínas de Neoplasias/análise , Fatores de Crescimento Neural/fisiologia , Processamento de Proteína Pós-Traducional , Proteínas Tirosina Fosfatases/análise , Proteínas Tirosina Fosfatases/fisiologia , Proteínas Tirosina Quinases , RNA Neoplásico/análise , Receptores Proteína Tirosina Quinases , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores , Células Tumorais Cultivadas
19.
Lab Invest ; 84(1): 8-20, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14631378

RESUMO

Local invasiveness is a characteristic feature of glioblastoma that makes surgical resection nearly impossible and accounts in large part for its poor prognosis. To identify mechanisms underlying glioblastoma invasion and motility, we used Transwell invasion chambers to select for a more potently invasive subpopulation of U87MG human glioblastoma cells. The stable population of tumor cells (U87-C1) obtained through this in vitro selection process were three times more invasive than parental U87MG cells and demonstrated faster monolayer wound healing and enhanced radial motility from cell spheroids. This enhanced invasiveness was associated with an 80% increase in matrix metalloproteinase 2 (MMP-2) activation. No differences in expression levels of pro-MMP-2, membrane-type matrix metalloproteinase I (MT1-MMP), or integrin alphavbeta3 (mediators of MMP-2 activation) were detected. However, U87-C1 cells exhibited two-fold elevation of tissue inhibitor of metalloproteinases (TIMP)-2 mRNA and protein relative to parental cells. Exogenous addition of comparable levels of purified TIMP-2 to parental U87MG cells increased MMP-2 activation and invasion. Similarly, U87MG cells engineered to overexpress TIMP-2 at the same levels as U87-C1 cells also demonstrated increased MMP-2 activation, indicating that an increase in physiological levels of TIMP-2 can promote MMP-2 activation and invasion in glioblastoma cells. However, exogenous administration or recombinant overexpression of higher amounts of TIMP-2 in U87MG cells resulted in inhibition of MMP-2 activation. These results demonstrate that the complex balance between TIMP-2 and MMP-2 is a critical determinant of glioblastoma invasion, and indicate that increasing TIMP-2 in glioblastoma patients may potentially cause adverse effects, particularly in tumors containing high levels of MT1-MMP and MMP-2.


Assuntos
Glioblastoma/metabolismo , Metaloproteinase 2 da Matriz/biossíntese , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/metabolismo , Relação Dose-Resposta a Droga , Glioblastoma/tratamento farmacológico , Humanos , Metaloproteinases da Matriz Associadas à Membrana , Metaloendopeptidases/biossíntese , Metaloendopeptidases/genética , Invasividade Neoplásica , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esferoides Celulares/citologia , Esferoides Celulares/metabolismo , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/farmacologia , Transfecção , Regulação para Cima
20.
Oncogene ; 22(15): 2361-73, 2003 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-12700671

RESUMO

Epidermal growth factor receptor (EGFR) overexpression occurs in nearly 50% of cases of glioblastoma (GBM), but its clinical and biological implications are not well understood. We have used Affymetrix high-density oligonucleotide arrays to demonstrate that EGFR-overexpressing GBMs (EGFR+) have a distinct global gene transcriptional profile. We show that the expression of 90 genes can distinguish EGFR+ from EGFR nonexpressing (EGFR-) GBMs, including a number of genes known to act as growth/survival factors for GBMs. We have also uncovered two additional novel molecular subtypes of GBMs, one of which is characterized by coordinate upregulation of contiguous genes on chromosome 12q13-15 and expression of both astrocytic and oligodendroglial genes. These results define distinct molecular subtypes of GBMs that may be important in disease stratification, and in the discovery and assessment of GBM treatment strategies.


Assuntos
Neoplasias Encefálicas/classificação , Perfilação da Expressão Gênica , Glioblastoma/classificação , Análise de Sequência com Séries de Oligonucleotídeos , Astrócitos/metabolismo , Astrócitos/patologia , Biópsia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Diferenciação Celular , Linhagem da Célula , Cromossomos Humanos Par 12/genética , Receptores ErbB/biossíntese , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Oligodendroglia/metabolismo , Oligodendroglia/patologia , RNA Mensageiro/genética , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnica de Subtração , Transcrição Gênica
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