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1.
World J Diabetes ; 13(4): 319-337, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35582669

RESUMO

Insulin, a key pleiotropic hormone, regulates metabolism through several signaling pathways in target tissues including skeletal muscle, liver, and brain. In the brain, insulin modulates learning and memory, and impaired insulin signaling is associated with metabolic dysregulation and neurodegenerative diseases. At the receptor level, in aging and Alzheimer's disease (AD) models, the amount of insulin receptors and their functions are decreased. Clinical and animal model studies suggest that memory improvements are due to changes in insulin levels. Furthermore, diabetes mellitus (DM) and insulin resistance are associated with age-related cognitive decline, increased levels of ß-amyloid peptide, phosphorylation of tau protein; oxidative stress, pro-inflammatory cytokine production, and dyslipidemia. Recent evidence shows that deleting brain insulin receptors leads to mild obesity and insulin resistance without influencing brain size and apoptosis development. Conversely, deleting insulin-like growth factor 1 receptor (IGF-1R) affects brain size and development, and contributes to behavior changes. Insulin is synthesized locally in the brain and is released from the neurons. Here, we reviewed proposed pathophysiological hypotheses to explain increased risk of dementia in the presence of DM. Regardless of the exact sequence of events leading to neurodegeneration, there is strong evidence that mitochondrial dysfunction plays a key role in AD and DM. A triple transgenic mouse model of AD showed mitochondrial dysfunction, oxidative stress, and loss of synaptic integrity. These alterations are comparable to those induced in wild-type mice treated with sucrose, which is consistent with the proposal that mitochondrial alterations are associated with DM and contribute to AD development. Alterations in insulin/IGF-1 signaling in DM could lead to mitochondrial dysfunction and low antioxidant capacity of the cell. Thus, insulin/IGF-1 signaling is important for increased neural processing and systemic metabolism, and could be a specific target for therapeutic strategies to decrease alterations associated with age-related cognitive decline.

2.
Cardiol Rev ; 27(4): 179-181, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31180937

RESUMO

Multiple strategies have been implemented to increase the donor pool to avoid transplant wait-list mortality. The approval of highly effective direct-acting antiviral regimens for the treatment of hepatitis C virus (HCV) has enabled expansion of the donor pool by allowing the transplantation of organs from HCV-viremic donors to HCV-negative recipients. Multiple centers have recently published data on outcomes of heart transplantation from HCV-viremic heart donors to HCV-negative recipients, with acceptable posttransplant outcomes. However, areas of uncertainty remain, particularly in the long-term risks of intentional HCV transmission, as well as the possibility that sustained virologic response may not be achieved. In this article, we review the literature illustrating both the risks and benefits of transplantation of organs from HCV-viremic donors to HCV-negative recipients. We also present the data collected at our institution regarding this special patient population.


Assuntos
Transplante de Coração/métodos , Hepacivirus , Hepatite C/cirurgia , Doadores de Tecidos , Transplantados , Viremia/cirurgia , Hepatite C/virologia , Humanos , Prognóstico , Viremia/virologia
3.
Dis Markers ; 2019: 8761860, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30906485

RESUMO

Early diagnosis represents the target of contemporary medicine and has an important role in the prognosis and further treatment. Saliva is a biofluid that generated a high interest among researchers due to its multiple advantages over other body fluids. The multitude of components that can act as biomarkers influenced the existing technologies to develop protocols that could allow saliva to become the new noninvasive diagnostic method. Saliva as a diagnostic tool can bring substantial addition to the diagnostic armamentarium, providing important information about oral and general health. The diagnostic applications of saliva extended and had a rapid evolution due to the advancement in salivaomics. The present review summarizes the latest researches in saliva-related studies and explores the information and correlations that saliva can offer regarding the systemic and oral diseases, highlighting its great potential of diagnosis. It is expected that in the future specific guidelines and results regarding the salivary diagnostics are to be available, together with high-sensitivity and specificity tests for multiple systemic and oral diseases.


Assuntos
Doenças Cardiovasculares/metabolismo , Doenças da Boca/metabolismo , Saliva/metabolismo , Biomarcadores/metabolismo , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Humanos , Técnicas de Diagnóstico Molecular/métodos , Doenças da Boca/genética , Doenças da Boca/patologia
4.
J Immunol Res ; 2018: 7169081, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30406153

RESUMO

Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is a glycoprotein belonging to the carcinoembryonic antigen (CEA) family that is expressed on a wide variety of cells and holds a complex role in inflammation through its alternate splicing and generation of various isoforms, mediating intricate mechanisms of modulation and dysregulation. Initially regarded as a tumor suppressor as its expression shows considerable downregulation within the epithelia in the early phases of many solid cancers, CEACAM1 has been linked lately to the progression of malignancy and metastatic spread as various papers point to its role in tumor progression, angiogenesis, and invasion. We reviewed the literature and discussed the various expression patterns of CEACAM1 in different types of tumors, describing its structure and general biologic functions and emphasizing the most significant findings that link this molecule to poor prognosis. The importance of understanding the role of CEACAM1 in cell transformation stands not only in this adhesion molecule's value as a prognostic factor but also in its promising premise as a potential new molecular target that could be exploited as a specific cancer therapy.


Assuntos
Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Moléculas de Adesão Celular/metabolismo , Células Epiteliais/fisiologia , Inflamação/metabolismo , Neoplasias/metabolismo , Processamento Alternativo , Antígeno Carcinoembrionário/metabolismo , Transformação Celular Neoplásica , Humanos , Metástase Neoplásica , Transcriptoma , Proteínas Supressoras de Tumor/metabolismo
5.
Clin Cancer Res ; 24(10): 2276-2284, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29506988

RESUMO

Purpose: Duligotuzumab is a dual-action antibody directed against EGFR and HER3.Experimental Design: Metastatic colorectal cancer (mCRC) patients with KRAS ex2 wild-type received duligotuzumab or cetuximab and FOLFIRI until progression or intolerable toxicity. Mandatory tumor samples underwent mutation and biomarker analysis. Efficacy analysis was conducted in patients with RAS exon 2/3 wild-type tumors.Results: Of 134 randomly assigned patients, 98 had RAS ex2/3 wild-type. Duligotuzumab provided no progression-free survival (PFS) or overall survival (OS) benefit compared with cetuximab, although there was a trend for a lower objective response rate (ORR) in the duligotuzumab arm. No relationship was seen between PFS or ORR and ERBB3, NRG1, or AREG expression. There were fewer skin rash events for duligotuzumab but more diarrhea. Although the incidence of grade ≥3 AEs was similar, the frequency of serious AEs was higher for duligotuzumab.Conclusions: Duligotuzumab plus FOLFIRI did not appear to improve the outcomes in patients with RAS exon 2/3 wild-type mCRC compared with cetuximab + FOLFIRI. Clin Cancer Res; 24(10); 2276-84. ©2018 AACR.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais , Camptotecina/efeitos adversos , Camptotecina/uso terapêutico , Cetuximab/administração & dosagem , Cetuximab/farmacocinética , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Feminino , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Genes ras , Humanos , Imunoglobulina G/administração & dosagem , Imunoglobulina G/farmacologia , Leucovorina/efeitos adversos , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Mutação , Metástase Neoplásica , Estadiamento de Neoplasias , Intervalo Livre de Progressão , Retratamento , Resultado do Tratamento , Adulto Jovem
6.
Medchemcomm ; 8(12): 2258-2262, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30108741

RESUMO

Novel oxazolidin-2-one-linked 1,2,3-triazole derivatives (4a-k) were synthesized by straightforward and versatile azide-enolate (3 + 2) cycloaddition. The series of compounds was screened for antifungal activity against four filamentous fungi as well as six yeast species of Candida spp. According to their efficiency and breadth of scope, they can be ordered as 4k > 4d > 4h > 4a, especially in relation to the activity displayed against Candida glabrata ATCC-34138, Trichosporon cutaneum ATCC-28592 and Mucor hiemalis ATCC-8690, i.e. compounds 4d, 4h and 4k showed excellent activity against C. glabrata (MIC 0.12, 0.25 and 0.12 µg mL-1, respectively), better than that of itraconazole (MIC 1 µg ml-1). The activity of compound 4d (MIC = 2 µg mL-1) was higher than that observed for the standard antifungal drug (MIC = 8 µg mL-1) against Trichosporon cutaneum, while compound 4k displayed an excellent antimycotic activity against Mucor hiemalis (MIC = 2 µg mL-1vs. 4 µg mL-1 for itraconazole). In addition, we describe herein a novel mild and eco-friendly synthetic protocol for obtaining ß-ketosulfones (adducts to afford compounds 4a-k) from α-brominated carbonyls in an aqueous nanomicellar medium at room temperature.

7.
Science ; 349(6245): 309-12, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26113639

RESUMO

Morphinan alkaloids from the opium poppy are used for pain relief. The direction of metabolites to morphinan biosynthesis requires isomerization of (S)- to (R)-reticuline. Characterization of high-reticuline poppy mutants revealed a genetic locus, designated STORR [(S)- to (R)-reticuline] that encodes both cytochrome P450 and oxidoreductase modules, the latter belonging to the aldo-keto reductase family. Metabolite analysis of mutant alleles and heterologous expression demonstrate that the P450 module is responsible for the conversion of (S)-reticuline to 1,2-dehydroreticuline, whereas the oxidoreductase module converts 1,2-dehydroreticuline to (R)-reticuline rather than functioning as a P450 redox partner. Proteomic analysis confirmed that these two modules are contained on a single polypeptide in vivo. This modular assembly implies a selection pressure favoring substrate channeling. The fusion protein STORR may enable microbial-based morphinan production.


Assuntos
Benzilisoquinolinas/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Isoquinolinas/metabolismo , Morfinanos/metabolismo , Papaver/enzimologia , Proteínas de Plantas/metabolismo , Compostos de Amônio Quaternário/metabolismo , Sequência de Bases , Benzilisoquinolinas/química , Sistema Enzimático do Citocromo P-450/genética , Loci Gênicos , Isoquinolinas/química , Dados de Sequência Molecular , Morfinanos/química , Mutação , Oxirredução , Papaver/genética , Proteínas de Plantas/genética , Compostos de Amônio Quaternário/química
8.
J Exp Anal Behav ; 103(2): 349-60, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25766450

RESUMO

Equivalence class formation by college students was influenced through the prior acquisition of conditional discriminative functions by one of the abstract stimuli (C) in the to-be-formed classes. Participants in the GR-0, GR-1, and GR-5 groups attempted to form classes under the simultaneous protocol, after mastering 0, 1, or 5 conditional relations between C and other abstract stimuli (V, W, X, Y, Z) that were not included in the to-be-formed classes (ABCDE). Participants in the GR-many group attempted to form classes that contained four abstract stimuli and one meaningful picture as the C stimulus. In the GR-0, GR-1, GR-5, and GR-many groups, classes were formed by 17, 25, 58, and 67% of participants, respectively. Thus, likelihood of class formation was enhanced by the prior formation of five C-based conditional relations (the GR-5 vs. GR-0 condition), or the inclusion of a meaningful stimulus as a class member (the GR-many vs. GR-0 condition). The GR-5 and GR-many conditions produced very similar yields, indicating that class formation was enhanced to a similar degree by including a meaningful stimulus or an abstract stimulus that had become a member of five conditional relations prior to equivalence class formation. Finally, the low and high yields produced by the GR-1 and GR-5 conditions showed that the class enhancement effect of the GR-5 condition was due to the number of conditional relations established during preliminary training and not to the sheer amount of reinforcement provided while learning these conditional relations. Class enhancement produced by meaningful stimuli, then, can be attributed to their acquired conditional discriminative functions as well as their discriminative, connotative, and denotative properties.


Assuntos
Aprendizagem por Discriminação , Adolescente , Adulto , Formação de Conceito , Condicionamento Psicológico , Humanos , Pessoa de Meia-Idade , Estimulação Luminosa , Reforço Psicológico , Adulto Jovem
9.
Mol Cell Biol ; 33(8): 1621-31, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23401859

RESUMO

Substrate engagement by F-box proteins promotes NEDD8 modification of cullins, which is necessary for the activation of cullin-RING E3 ubiquitin ligases (CRLs). However, the mechanism by which substrate recruitment triggers cullin neddylation remains unclear. Here, we identify DCNL1 (defective in cullin neddylation 1-like 1) as a component of CRL2 called ECV (elongins BC/CUL2/VHL) and show that molecular suppression of DCNL1 attenuates CUL2 neddylation. DCNL1 via its DAD patch binds to CUL2 but is also able to bind VHL independent of CUL2 and the DAD patch. The engagement of the substrate hypoxia-inducible factor 1α (HIF1α) to the substrate receptor VHL increases DCNL1 binding to VHL as well as to CUL2. Notably, an engineered mutant form of HIF1α that associates with CUL2, but not DCNL1, fails to trigger CUL2 neddylation and retains ECV in an inactive state. These findings support a model in which substrate engagement prompts DCNL1 recruitment that facilitates the initiation of CUL2 neddylation and define DCNL1 as a "substrate sensor switch" for ECV activation.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Culina/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular , Células HEK293 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Peptídeos e Proteínas de Sinalização Intracelular , Mutação , Ligação Proteica , Proteínas , Proteínas Proto-Oncogênicas , Interferência de RNA , RNA Interferente Pequeno
10.
Cleve Clin J Med ; 78(9): 585-92, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21885690

RESUMO

Blood tests are available that measure levels of immunoglobulin E (IgE) against specific allergens such as foods, inhalants, medications, latex, and venoms. These tests can confirm the diagnosis of an allergic disorder, supplementing a clinical history consistent with an immediate allergic reaction. They are particularly useful when skin testing cannot or should not be performed.


Assuntos
Testes Hematológicos/métodos , Hipersensibilidade Imediata/sangue , Imunoglobulina E/sangue , Hipersensibilidade a Drogas/sangue , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade Alimentar/sangue , Hipersensibilidade Alimentar/diagnóstico , Testes Hematológicos/instrumentação , Humanos , Imunoensaio/instrumentação , Imunoensaio/métodos , Imunoglobulina E/imunologia , Exposição por Inalação , Mordeduras e Picadas de Insetos/complicações , Medição de Risco , Sensibilidade e Especificidade
11.
Nat Med ; 17(7): 845-53, 2011 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-21685897

RESUMO

Chuvash polycythemia is a rare congenital form of polycythemia caused by homozygous R200W and H191D mutations in the VHL (von Hippel-Lindau) gene, whose gene product is the principal negative regulator of hypoxia-inducible factor. However, the molecular mechanisms underlying some of the hallmark abnormalities of Chuvash polycythemia, such as hypersensitivity to erythropoietin, are unclear. Here we show that VHL directly binds suppressor of cytokine signaling 1 (SOCS1) to form a heterodimeric E3 ligase that targets phosphorylated JAK2 (pJAK2) for ubiquitin-mediated destruction. In contrast, Chuvash polycythemia-associated VHL mutants have altered affinity for SOCS1 and do not engage with and degrade pJAK2. Systemic administration of a highly selective JAK2 inhibitor, TG101209, reversed the disease phenotype in Vhl(R200W/R200W) knock-in mice, an experimental model that recapitulates human Chuvash polycythemia. These results show that VHL is a SOCS1-cooperative negative regulator of JAK2 and provide biochemical and preclinical support for JAK2-targeted therapy in individuals with Chuvash polycythemia.


Assuntos
Janus Quinase 2/fisiologia , Policitemia/etiologia , Proteínas Supressoras da Sinalização de Citocina/genética , Ubiquitina-Proteína Ligases/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Animais , Modelos Animais de Doenças , Humanos , Janus Quinase 2/antagonistas & inibidores , Camundongos , Mutação/genética , Policitemia/genética , Multimerização Proteica/genética , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina/fisiologia , Ubiquitina-Proteína Ligases/fisiologia , Proteína Supressora de Tumor Von Hippel-Lindau/fisiologia
12.
Haematologica ; 96(10): 1406-14, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21685469

RESUMO

BACKGROUND: KANK1-PDGFRB is a fusion gene generated by the t(5;9) translocation between KANK1 and the platelet-derived growth factor receptor beta gene PDGFRB. This hybrid was identified in a myeloproliferative neoplasm featuring severe thrombocythemia, in the absence of the JAK2 V617F mutation. DESIGN AND METHODS: KANK1-PDGFRB was transduced into Ba/F3 cells and CD34(+) human progenitor cells to gain insights into the mechanisms whereby this fusion gene transforms cells. RESULTS: Although platelet-derived growth factor receptors are capable of activating JAK2, KANK1-PDGFRß did not induce JAK2 phosphorylation in hematopoietic cells and a JAK inhibitor did not affect KANK1-PDGFRß-induced cell growth. Like JAK2 V617F, KANK1-PDGFRß constitutively activated STAT5 transcription factors, but this did not require JAK kinases. In addition KANK1-PDGFRß induced the phosphorylation of phospholipase C-γ, ERK1 and ERK2, like wild-type PDGFRß and TEL-PDGFRß, another hybrid protein found in myeloid malignancies. We next tested various mutant forms of KANK1-PDGFRß in Ba/F3 cells and human CD34(+) hematopoietic progenitors. The three coiled-coil domains located in the N-terminus of KANK1 were required for KANK1-PDGFRß-induced cell growth and signaling via STAT5 and ERK. However, the coiled-coils were not essential for KANK1-PDGFRß oligomerization, which could be mediated by another new oligomerization domain. KANK1-PDGFRß formed homotrimeric complexes and heavier oligomers. CONCLUSIONS: KANK1-PDGFRB is a unique example of a thrombocythemia-associated oncogene that does not signal via JAK2. The fusion protein is activated by multiple oligomerization domains, which are required for signaling and cell growth stimulation.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Janus Quinase 2/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Linhagem Celular Transformada , Proliferação de Células , Proteínas do Citoesqueleto , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células-Tronco Hematopoéticas/metabolismo , Humanos , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Proteínas de Fusão Oncogênica/genética , Fosforilação , Multimerização Proteica , Estrutura Terciária de Proteína , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Proteínas Supressoras de Tumor/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-22649382

RESUMO

The thrombopoietin receptor (TpoR) is a type I transmembrane protein that mediates the signaling functions of thrombopoietin (Tpo) in regulating megakaryocyte differentiation, platelet formation, and hematopoietic stem cell renewal. We probed the role of each of the four extracellular domain putative N-glycosylation sites for cell surface localization and function of the receptor. Single N-glycosylation mutants at any of the four sites were able to acquire the mature N-glycosylated pattern, but exhibited a decreased Tpo-dependent JAK2-STAT response in stably transduced Ba/F3 or Ba/F3-JAK2 cell lines. The ability of JAK2 to promote cell surface localization and stability of TpoR required the first N-glycosylation site (Asn117). In contrast, the third N-glycosylation site (Asn298) decreased receptor maturation and stability. TpoR mutants lacking three N-glycosylation sites were defective in maturation, but N-glycosylation on the single remaining site could be detected by sensitivity to PNGaseF. The TpoR mutant defective in all four N-glycosylation sites was severely impaired in plasma membrane localization and was degraded by the proteasome. N-glycosylation receptor mutants are not misfolded as, once localized on the cell surface in overexpression conditions, they can bind and respond to Tpo. Our data indicate that extracellular domain N-glycosylation sites regulate in a combinatorial manner cell surface localization of TpoR. We discuss how mutations around TpoR N-glycosylation sites might contribute to inefficient receptor traffic and disease.

14.
EMBO Mol Med ; 1(1): 66-78, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20049704

RESUMO

Tumour hypoxia promotes the accumulation of the otherwise oxygen-labile hypoxia-inducible factor (HIF)-alpha subunit whose expression is associated with cancer progression, poor prognosis and resistance to conventional radiation and chemotherapy. The oxygen-dependent degradation of HIF-alpha is carried out by the von Hippel-Lindau (VHL) protein-containing E3 that directly binds and ubiquitylates HIF-alpha for subsequent proteasomal destruction. Thus, the cellular proteins involved in the VHL-HIF pathway have been recognized as attractive molecular targets for cancer therapy. However, the various compounds designed to inhibit HIF-alpha or HIF-downstream targets, although promising, have shown limited success in the clinic. In the present study, we describe the bioengineering of VHL protein that removes the oxygen constraint in the recognition of HIF-alpha while preserving its E3 enzymatic activity. Using speckle variance-optical coherence tomography (sv-OCT), we demonstrate the dramatic inhibition of angiogenesis and growth regression of human renal cell carcinoma xenografts upon adenovirus-mediated delivery of the bioengineered VHL protein in a dorsal skin-fold window chamber model. These findings introduce the concept and feasibility of 'bio-tailored' enzymes in the treatment of HIF-overexpressing tumours.


Assuntos
Bioengenharia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Oxigênio/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Recombinantes de Fusão/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Adenoviridae/genética , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/terapia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Transferência de Genes , Proteínas de Fluorescência Verde/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/química , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/terapia , Camundongos , Necrose , Neovascularização Patológica/terapia , Plasmídeos/genética , Ligação Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína , Elementos de Resposta/genética , Transcrição Gênica/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Ann Oncol ; 19(2): 327-31, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18065408

RESUMO

BACKGROUND: The amount of residual disease after surgery is considered the most important factor influencing the survival of patients with advanced epithelial ovarian cancer (adEOC). In optimally treated patients with adEOC, there are no well-established prognostic factors [excluding International Federation of Gynecology and Obstetrics (FIGO) stage]. The aim of this retrospective study is to analyze the prognostic value of the CA-125 nadir after the completion of an optimal primary treatment. PATIENTS AND METHODS: Patients treated for adEOC were identified from January 1998 to December 2006. INCLUSION CRITERIA: elevated CA-125 at time of diagnosis (>35 kU/l); FIGO stage III-IV treated with optimal primary treatment (residual tumor <1 cm and carboplatin/taxane-based combination chemotherapy); and complete response to optimal primary treatment with normalization of CA-125. RESULTS: Patients, n = 96: 44 group A (< or =10 kU/l); 52 group B (11-35 kU/l). Median progression-free survival (PFS) was 42 and 20 months for groups A and B, respectively (P = 0.0087). Median overall survival (OS) was 84 and 43 months for groups A and B, respectively (P < 0.0001). The Cox model showed a highly significant impact on PFS and OS in relation to CA-125 nadir levels. CONCLUSIONS: The CA-125 nadir value is a strong independent prognostic factor for optimally treated adEOC after achieving a complete response.


Assuntos
Antígeno Ca-125/sangue , Invasividade Neoplásica/patologia , Neoplasias Epiteliais e Glandulares/sangue , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/mortalidade , Adulto , Idoso , Biomarcadores Tumorais/sangue , Quimioterapia Adjuvante , Estudos de Coortes , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Epiteliais e Glandulares/terapia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Ovariectomia/métodos , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Cirurgia de Second-Look , Sensibilidade e Especificidade , Espanha , Análise de Sobrevida , Fatores de Tempo
16.
Mol Cell Biol ; 27(1): 157-69, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17060462

RESUMO

The product of the von Hippel-Lindau gene (VHL) acts as the substrate-recognition component of an E3 ubiquitin ligase complex that ubiquitylates the catalytic alpha subunit of hypoxia-inducible factor (HIF) for oxygen-dependent destruction. Although emerging evidence supports the notion that deregulated accumulation of HIF upon the loss of VHL is crucial for the development of clear-cell renal cell carcinoma (CC-RCC), the molecular events downstream of HIF governing renal oncogenesis remain unclear. Here, we show that the expression of a homophilic adhesion molecule, E-cadherin, a major constituent of epithelial cell junctions whose loss is associated with the progression of epithelial cancers, is significantly down-regulated in primary CC-RCC and CC-RCC cell lines devoid of VHL. Reintroduction of wild-type VHL in CC-RCC (VHL(-/-)) cells markedly reduced the expression of E2 box-dependent E-cadherin-specific transcriptional repressors Snail and SIP1 and concomitantly restored E-cadherin expression. RNA interference-mediated knockdown of HIFalpha in CC-RCC (VHL(-/-)) cells likewise increased E-cadherin expression, while functional hypoxia or expression of VHL mutants incapable of promoting HIFalpha degradation attenuated E-cadherin expression, correlating with the disengagement of RNA polymerase II from the endogenous E-cadherin promoter/gene. These findings reveal a critical HIF-dependent molecular pathway connecting VHL, an established "gatekeeper" of the renal epithelium, with a major epithelial tumor suppressor, E-cadherin.


Assuntos
Caderinas/biossíntese , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas do Tecido Nervoso/fisiologia , Proteínas de Ligação a RNA/fisiologia , Fatores de Transcrição/fisiologia , Proteína Supressora de Tumor Von Hippel-Lindau/fisiologia , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Humanos , Rim/metabolismo , Regiões Promotoras Genéticas , Interferência de RNA , RNA Polimerase II/metabolismo , RNA Interferente Pequeno/metabolismo , Fatores de Transcrição da Família Snail , Frações Subcelulares/metabolismo
17.
Neoplasia ; 8(11): 956-63, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17132228

RESUMO

ECV is an E3 ubiquitin ligase complex, which is composed of elongins B and C, Rbx1, Cul2, and the substrate-conferring von Hippel-Lindau (VHL) tumor-suppressor protein that targets the catalytic alpha subunit of hypoxia-inducible factor (HIF) for oxygen-dependent ubiquitin-mediated destruction. Mutations in VHL that compromise proper HIFalpha regulation through ECV have been documented in the majority of renal cell carcinomas, underscoring the significance of the VHL-HIF pathway in renal epithelial oncogenesis. Recent evidence has shown that the modification of Cul2 by the ubiquitin-like molecule NEDD8 increases the activity of ECV to ubiquitylate HIFalpha. However, the underlying mechanism responsible for the NEDD8-mediated induction of ECV function is unknown. Here, we demonstrate that oxygen-dependent recognition of HIFalpha by VHL triggers Rbx1-dependent neddylation of Cul2, which preferentially engages the E2 ubiquitin-conjugating enzyme UbcH5a. These events establish a central role for the neddylation of Cul2 in a previously unrecognized, temporally coordinated activation of ECV with the recruitment of its substrate HIFalpha.


Assuntos
Proteínas Culina/fisiologia , Ubiquitina-Proteína Ligases/química , Ubiquitinas/fisiologia , Proteínas de Transporte/metabolismo , Domínio Catalítico , Linhagem Celular , Proteínas Culina/metabolismo , Humanos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas de Ligação ao Ferro/metabolismo , Modelos Biológicos , Mutação , Proteína NEDD8 , Oxigênio/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitinas/metabolismo
18.
Am J Physiol Renal Physiol ; 287(1): F1-6, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15180922

RESUMO

The majority of kidney cancers are caused by the mutation of the von Hippel-Lindau (VHL) tumor suppressor gene. VHL protein (pVHL) is part of an E3 ubiquitin ligase complex called VEC that is composed of elongin B, elongin C, cullin 2, NEDD8, and Rbx1. VEC targets a hypoxia-inducible factor (HIF) transcription factor for ubiquitin-mediated destruction selectively in the presence of oxygen. In the absence of wild-type pVHL, as in VHL patients or in the majority of sporadic clear cell renal cell carcinomas, HIF-responsive genes are inappropriately activated even under normoxia. Recent insights into the molecular mechanisms regulating the function of pVHL, and thereby HIF, in the context of kidney cancer are the focus of this review.


Assuntos
Carcinoma de Células Renais/genética , Carcinoma de Células Renais/fisiopatologia , Hipóxia Celular , Neoplasias Renais/genética , Neoplasias Renais/fisiopatologia , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/farmacologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/farmacologia , Doença de von Hippel-Lindau/genética , Genes Supressores de Tumor , Humanos , Mutação , Proteína Supressora de Tumor Von Hippel-Lindau , Doença de von Hippel-Lindau/fisiopatologia
19.
Rev Lat Am Enfermagem ; 10(1): 21-7, 2002.
Artigo em Português | MEDLINE | ID: mdl-12080584

RESUMO

This study aimed at analyzing the conformation of the Epidemiological Surveillance Service in Ribeirão Preto Municipal Health Secretariat under the orientation of the principles established by the Unified Health System and the perspective of Health Surveillance in face of the health care municipalization process occurring in the 1990s through the following dimensions: territory; problems; intersectoriality based on positive health concepts and on the paradigm of social health production. By means of a qualitative approach, bibliographical and documentation sources as well as 17 semi-structured interviews were used. Data were analyzed through the thematic analysis technique by which the following themes were identified: from "Monitoring" to "Educating and Preventing": practice in Epidemiological Surveillance--a proposal to work in the territory. It was concluded that the potentiality of actions related to Epidemiological Surveillance is associated with the perspective of working in the territory for the construction of Health Surveillance in order to assure the technical content of those actions as well as the participation of different professional categories in the same work project, which will not necessarily be performed by all professionals in the same health production process, territory or time.


Assuntos
Vigilância da População , Enfermagem em Saúde Pública , Brasil , Órgãos Governamentais , Humanos
20.
Rev. latinoam. enferm ; Rev. latinoam. enferm. (Online);10(1): 21-27, jan.-fev. 2002.
Artigo em Português | LILACS, BDENF - enfermagem (Brasil) | ID: lil-319390

RESUMO

Este estudo procurou analisar como se conforma a prática na vigilância epidemiológica na Secretaria Municipal da Saúde (SMS-RP) sob a orientaçäo dos princípios do SUS e da perspectiva da Vigilância em Saúde face ao processo d municipalizaçäo da saúde na década de 90, utilizando as seguintes dimensöes: território; problemas; intersetorialidade, referenciada pelo conceito positivo de saúde e pelo paradigma da produçäo social de saúde...


Assuntos
Humanos , Monitoramento Epidemiológico , Sistema Único de Saúde , Brasil , Entrevistas como Assunto , Sistemas Locais de Saúde
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