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1.
Aging (Albany NY) ; 14(12): 4959-4975, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35687897

RESUMO

To detect the epigenetic drift of time passing, we determined the genome-wide distributions of mono- and tri-methylated lysine 4 and acetylated and tri-methylated lysine 27 of histone H3 in the livers of healthy 3, 6 and 12 months old C57BL/6 mice. The comparison of different age profiles of histone H3 marks revealed global redistribution of histone H3 modifications with time, in particular in intergenic regions and near transcription start sites, as well as altered correlation between the profiles of different histone modifications. Moreover, feeding mice with caloric restriction diet, a treatment known to retard aging, reduced the extent of changes occurring during the first year of life in these genomic regions.


Assuntos
Código das Histonas , Histonas , Acetilação , Animais , Histonas/metabolismo , Fígado/metabolismo , Lisina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
2.
Cancer Res ; 81(3): 685-697, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33268528

RESUMO

Checkpoint inhibitors (CI) instigate anticancer immunity in many neoplastic diseases, albeit only in a fraction of patients. The clinical success of cyclophosphamide (C)-based haploidentical stem-cell transplants indicates that this drug may re-orchestrate the immune system. Using models of triple-negative breast cancer (TNBC) with different intratumoral immune contexture, we demonstrate that a combinatorial therapy of intermittent C, CI, and vinorelbine activates antigen-presenting cells (APC), and abrogates local and metastatic tumor growth by a T-cell-related effect. Single-cell transcriptome analysis of >50,000 intratumoral immune cells after therapy treatment showed a gene signature suggestive of a change resulting from exposure to a mitogen, ligand, or antigen for which it is specific, as well as APC-to-T-cell adhesion. This transcriptional program also increased intratumoral Tcf1+ stem-like CD8+ T cells and altered the balance between terminally and progenitor-exhausted T cells favoring the latter. Overall, our data support the clinical investigation of this therapy in TNBC. SIGNIFICANCE: A combinatorial therapy in mouse models of breast cancer increases checkpoint inhibition by activating antigen-presenting cells, enhancing intratumoral Tcf1+ stem-like CD8+ T cells, and increasing progenitor exhausted CD8+ T cells.


Assuntos
Antineoplásicos/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Ciclofosfamida/farmacologia , Inibidores de Checkpoint Imunológico/farmacologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Vinorelbina/farmacologia , Animais , Células Apresentadoras de Antígenos/efeitos dos fármacos , Células Apresentadoras de Antígenos/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linfócitos T CD8-Positivos/imunologia , Adesão Celular , Feminino , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Imunidade Celular , Camundongos , Camundongos Endogâmicos BALB C , Transcriptoma , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/imunologia
3.
J Immunother Cancer ; 8(1)2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32238471

RESUMO

The rapid rise to fame of immuno-oncology (IO) drugs has generated unprecedented interest in the industry, patients and doctors, and has had a major impact in the treatment of most cancers. An interesting aspect in the clinical development of many IO agents is the increasing reliance on nonconventional trial design, including the so-called 'master protocols' that incorporate various adaptive features and often heavily rely on biomarkers to select patient populations most likely to benefit. These novel designs promise to maximize the clinical benefit that can be reaped from clinical research, but are not without costs. Their acceptance as solid evidence basis for use outside of the research context requires profound cultural changes by multiple stakeholders, including regulatory bodies, decision-makers, statisticians, researchers, doctors and, most importantly, patients. Here we review characteristics of recent and ongoing trials testing IO drugs with unconventional design, and we highlight trends and critical aspects.


Assuntos
Imunoterapia/métodos , Oncologia/métodos , Neoplasias/terapia , Humanos
4.
JCO Precis Oncol ; 2: 1-16, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35135136

RESUMO

PURPOSE: Trials that accrue participants on the basis of genetic biomarkers are a powerful means of testing targeted drugs, but they are often complicated by the rarity of the biomarker-positive population. Umbrella trials circumvent this by testing multiple hypotheses to maximize accrual. However, bigger trials have higher chances of conflicting treatment allocations because of the coexistence of multiple actionable alterations; allocation strategies greatly affect the efficiency of enrollment and should be carefully planned on the basis of relative mutation frequencies, leveraging information from large sequencing projects. METHODS: We developed software named Precision Trial Drawer (PTD) to estimate parameters that are useful for designing precision trials, most importantly, the number of patients needed to molecularly screen (NNMS) and the allocation rule that maximizes patient accrual on the basis of mutation frequency, systematically assigning patients with conflicting allocations to the drug associated with the rarer mutation. We used data from The Cancer Genome Atlas to show their potential in a 10-arm imaginary trial of multiple cancers on the basis of genetic alterations suggested by the past Molecular Analysis for Personalised Therapy (MAP) conference. We validated PTD predictions versus real data from the SHIVA (A Randomized Phase II Trial Comparing Therapy Based on Tumor Molecular Profiling Versus Conventional Therapy in Patients With Refractory Cancer) trial. RESULTS: In the MAP imaginary trial, PTD-optimized allocation reduces number of patients needed to molecularly screen by up to 71.8% (3.5 times) compared with nonoptimal trial designs. In the SHIVA trial, PTD correctly predicted the fraction of patients with actionable alterations (33.51% [95% CI, 29.4% to 37.6%] in imaginary v 32.92% [95% CI, 28.2% to 37.6%] expected) and allocation to specific treatment groups (RAS/MEK, PI3K/mTOR, or both). CONCLUSION: PTD correctly predicts crucial parameters for the design of multiarm genetic biomarker-driven trials. PTD is available as a package in the R programming language and as an open-access Web-based app. It represents a useful resource for the community of precision oncology trialists. The Web-based app is available at https://gmelloni.github.io/ptd/shinyapp.html.

6.
Cancer Discov ; 6(6): 650-63, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27179036

RESUMO

UNLABELLED: The identification of genes maintaining cancer growth is critical to our understanding of tumorigenesis. We report the first in vivo genetic screen of patient-derived tumors, using metastatic melanomas and targeting 236 chromatin genes by expression of specific shRNA libraries. Our screens revealed unprecedented numerosity of genes indispensable for tumor growth (∼50% of tested genes) and unexpected functional heterogeneity among patients (<15% in common). Notably, these genes were not activated by somatic mutations in the same patients and are therefore distinguished from mutated cancer driver genes. We analyzed underlying molecular mechanisms of one of the identified genes, the Histone-lysine N-methyltransferase KMT2D, and showed that it promotes tumorigenesis by dysregulating a subset of transcriptional enhancers and target genes involved in cell migration. The assembly of enhancer genomic patterns by activated KMT2D was highly patient-specific, regardless of the identity of transcriptional targets, suggesting that KMT2D might be activated by distinct upstream signaling pathways. SIGNIFICANCE: Drug targeting of biologically relevant cancer-associated mutations is considered a critical strategy to control cancer growth. Our functional in vivo genetic screens of patient-derived tumors showed unprecedented numerosity and interpatient heterogeneity of genes that are essential for tumor growth, but not mutated, suggesting that multiple, patient-specific signaling pathways are activated in tumors. Cancer Discov; 6(6); 650-63. ©2016 AACR.This article is highlighted in the In This Issue feature, p. 561.


Assuntos
Transformação Celular Neoplásica/genética , Estudos de Associação Genética , Testes Genéticos , Neoplasias/diagnóstico , Neoplasias/genética , Fenótipo , Animais , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Biologia Computacional/métodos , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Elementos Facilitadores Genéticos , Epigênese Genética , Epigenômica/métodos , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Xenoenxertos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Metástase Neoplásica , Proteínas de Neoplasias/metabolismo , Ligação Proteica , RNA Interferente Pequeno/genética , Reprodutibilidade dos Testes
7.
Aging Cell ; 15(4): 661-72, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27076121

RESUMO

NGF has been implicated in forebrain neuroprotection from amyloidogenesis and Alzheimer's disease (AD). However, the underlying molecular mechanisms are still poorly understood. Here, we investigated the role of NGF signalling in the metabolism of amyloid precursor protein (APP) in forebrain neurons using primary cultures of septal neurons and acute septo-hippocampal brain slices. In this study, we show that NGF controls the basal level of APP phosphorylation at Thr668 (T668) by downregulating the activity of the Ser/Thr kinase JNK(p54) through the Tyr kinase signalling adaptor SH2-containing sequence C (ShcC). We also found that the specific NGF receptor, Tyr kinase A (TrkA), which is known to bind to APP, fails to interact with the fraction of APP molecules phosphorylated at T668 (APP(pT668) ). Accordingly, the amount of TrkA bound to APP is significantly reduced in the hippocampus of ShcC KO mice and of patients with AD in which elevated APP(pT668) levels are detected. NGF promotes TrkA binding to APP and APP trafficking to the Golgi, where APP-BACE interaction is hindered, finally resulting in reduced generation of sAPPß, CTFß and amyloid-beta (1-42). These results demonstrate that NGF signalling directly controls basal APP phosphorylation, subcellular localization and BACE cleavage, and pave the way for novel approaches specifically targeting ShcC signalling and/or the APP-TrkA interaction in AD therapy.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/metabolismo , Regulação para Baixo/efeitos dos fármacos , Fator de Crescimento Neural/farmacologia , Fosfotreonina/metabolismo , Adulto , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Ácido Aspártico Endopeptidases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Deleção de Genes , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/metabolismo , Hipocampo/patologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Células PC12 , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Ratos , Receptor trkA/metabolismo , Proteína 3 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo
8.
J Transl Med ; 13: 360, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26578263

RESUMO

Alliance Against Cancer (ACC) was established in Rome in 2002 as a consortium of six Italian comprehensive cancer centers (Founders). The aims of ACC were to promote a network among Italian oncologic institutions in order to develop specific, advanced projects in clinical and translational research. During the following years, many additional full and associate members joined ACC, that presently includes the National Institute of Health, 17 research-oriented hospitals, scientific and patient organizations. Furthermore, in the last three years ACC underwent a reorganization process that redesigned the structure, governance and major activities. The present goal of ACC is to achieve high standards of care across Italy, to implement and harmonize principles of modern personalized and precision medicine, by developing cost effective processes and to provide tailored information to cancer patients. We herein summarize some of the major initiatives that ACC is currently developing to reach its goal, including tumor genetic screening programs, establishment of clinical trial programs for cancer patients treated in Italian cancer centers, facilitate their access to innovative drugs under development, improve quality through an European accreditation process (European Organization of Cancer Institutes), and develop international partnerships. In conclusion, ACC is a growing organization, trying to respond to the need of networking in Italy and may contribute significantly to improve the way we face cancer in Europe.


Assuntos
Pesquisa Biomédica , Institutos de Câncer/organização & administração , Neoplasias/patologia , Neoplasias/terapia , Humanos , Itália , Medicina de Precisão
9.
Curr Protoc Cytom ; 70: 7.41.1-15, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25271961

RESUMO

One of the major limitations of flow cytometry (FCM) is the absence of an intracellular view. Automated microscopy and image analysis, together with technological developments, led to new approaches in cytometry that bypass the above limitation, introducing high resolution, high content, and large statistical sampling. However, few attempts have been made, until now, to translate the wide repertoire of FCM assays into high-content image screening. This unit describes the implementation of an acquisition and analysis protocol for evaluation of the cell cycle by automated microscopy. The approach grants the possibility to perform simultaneous analysis of a high number of different parameters. A large part of this unit is devoted to the description of hardware features that can optimize the recorded information together with the acquisition and analysis procedures employed to produce good-quality data.


Assuntos
Automação , Ciclo Celular , Processamento de Imagem Assistida por Computador , Microscopia , Animais , Automação/instrumentação , Automação/métodos , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Microscopia/instrumentação , Microscopia/métodos
10.
Curr Protoc Cytom ; 70: 7.42.1-14, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25271962

RESUMO

Optical fluorescence microscopy offers a wide range of technological solutions to address many questions in biomedical research. Spatial resolution has been greatly improved by the use of confocal microscopes, providing a 3-D analysis of the intracellular space. Automation has contributed to make confocal analysis available for high-content image cytometry studies. However, the storage, browsing, and analysis of the amount of data generated can challenge the feasibility of such studies. Presented in this chapter is a multistep acquisition and analysis protocol that can bypass such difficulties by an analysis-driven data collection. Cell-cycle analysis of low-resolution data can be employed to select cell populations of interest that can then be imaged at extremely high resolution and subjected to high-content analysis.


Assuntos
Ciclo Celular , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Animais , Humanos , Microscopia Confocal/instrumentação , Microscopia Confocal/métodos , Microscopia de Fluorescência/instrumentação , Microscopia de Fluorescência/métodos
11.
Ann Thorac Surg ; 97(2): 480-3, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24370201

RESUMO

BACKGROUND: Bronchopleural fistula after lung resection still represents a challenging life-threatening complication for thoracic surgeons. Considering its extremely high mortality rate, an effective treatment is urgently required. Our project investigated the hypothesis of experimental bronchopleural fistula closure by bronchoscopic injection of autologous bone marrow-derived mesenchymal stem cells into the cavity of the fistula, evaluating its feasibility and safety in a large animal model. METHODS: An experimental bronchopleural fistula was created in 9 goats after right upper tracheal lobectomy. The animals were randomly assigned to two groups: one received autologous bone marrow-derived mesenchymal stem cell bronchoscopic transplantation; the other received standard bronchoscopic fibrin glue injection. RESULTS: All animals receiving bronchoscopic stem cell transplantation presented fistula closure by extraluminal fibroblast proliferation and collagenous matrix development; none (0%) died during the study period. All animals receiving standard treatment still presented bronchopleural fistula; 2 of them (40%) died. Findings were confirmed by pathology examination, computed tomography, and magnetic resonance imaging. CONCLUSIONS: Bronchoscopic transplantation of bone marrow-derived mesenchymal stem cells effectively closes experimental bronchopleural fistula by extraluminal fibroblast proliferation and collagenous matrix development. Stem cells may play a crucial role in the treatment of postresectional bronchopleural fistula after standard lung resection. Although these results provide a basis for the development of clinical therapeutic strategies, the exact mechanism by which they are obtained is not yet completely clear; further studies are required to understand exactly how stem cells work in this field.


Assuntos
Fístula Brônquica/cirurgia , Doenças Pleurais/cirurgia , Fístula do Sistema Respiratório/cirurgia , Transplante de Células-Tronco , Animais , Modelos Animais de Doenças , Feminino , Cabras , Indução de Remissão
12.
Diabetes ; 63(4): 1353-65, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24270983

RESUMO

Diabetes compromises the bone marrow (BM) microenvironment and reduces the number of circulating CD34(+) cells. Diabetic autonomic neuropathy (DAN) may impact the BM, because the sympathetic nervous system is prominently involved in BM stem cell trafficking. We hypothesize that neuropathy of the BM affects stem cell mobilization and vascular recovery after ischemia in patients with diabetes. We report that, in patients, cardiovascular DAN was associated with fewer circulating CD34(+) cells. Experimental diabetes (streptozotocin-induced and ob/ob mice) or chemical sympathectomy in mice resulted in BM autonomic neuropathy, impaired Lin(-)cKit(+)Sca1(+) (LKS) cell and endothelial progenitor cell (EPC; CD34(+)Flk1(+)) mobilization, and vascular recovery after ischemia. DAN increased the expression of the 66-kDa protein from the src homology and collagen homology domain (p66Shc) and reduced the expression of sirtuin 1 (Sirt1) in mice and humans. p66Shc knockout (KO) in diabetic mice prevented DAN in the BM, and rescued defective LKS cell and EPC mobilization. Hematopoietic Sirt1 KO mimicked the diabetic mobilization defect, whereas hematopoietic Sirt1 overexpression in diabetes rescued defective mobilization and vascular repair. Through p66Shc and Sirt1, diabetes and sympathectomy elevated the expression of various adhesion molecules, including CD62L. CD62L KO partially rescued the defective stem/progenitor cell mobilization. In conclusion, autonomic neuropathy in the BM impairs stem cell mobilization in diabetes with dysregulation of the life-span regulators p66Shc and Sirt1.


Assuntos
Medula Óssea/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Mobilização de Células-Tronco Hematopoéticas , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Sirtuína 1/biossíntese , Idoso , Animais , Células Cultivadas , Diabetes Mellitus Experimental/fisiopatologia , Regulação para Baixo , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src
13.
Methods Enzymol ; 528: 99-110, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23849861

RESUMO

Reactive oxygen species (ROS), mainly originated from mitochondrial respiration, are critical inducers of oxidative damage and involved in tissue dysfunction. It is not clear, however, whether oxidative stress is the result of an active gene program or it is the by-product of physiological processes. Recent findings demonstrate that ROS are produced by mitochondria in a controlled way through specialized enzymes, including p66Shc, and take part in cellular process aimed to ensure adaptation and fitness. Therefore, genes generating specifically ROS are selected determinants of life span in response to different environmental conditions.


Assuntos
Mitocôndrias Hepáticas/efeitos dos fármacos , Espécies Reativas de Oxigênio/agonistas , Proteínas Adaptadoras da Sinalização Shc/farmacologia , Animais , Apoptose/efeitos dos fármacos , Regulação da Temperatura Corporal/fisiologia , Ciclosporina/farmacologia , Técnicas Eletroquímicas , Escherichia coli/genética , Escherichia coli/metabolismo , Etilmaleimida/farmacologia , Humanos , Camundongos , Mitocôndrias Hepáticas/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/antagonistas & inibidores , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Oxirredução , Estresse Oxidativo , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Isoformas de Proteínas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Proteínas Adaptadoras da Sinalização Shc/biossíntese , Proteínas Adaptadoras da Sinalização Shc/genética , Transdução de Sinais , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src
14.
Oxid Med Cell Longev ; 2013: 719407, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23766859

RESUMO

Mitochondrial-mediated oxidative stress and apoptosis play a crucial role in neurodegenerative disease and aging. Both mitochondrial permeability transition (PT) and swelling of mitochondria have been involved in neurodegeneration. Indeed, knockout mice for cyclophilin-D (Cyc-D), a key regulatory component of the PT pore (PTP) that triggers mitochondrial swelling, resulted to be protected in preclinical models of multiple sclerosis (MS), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). However, how neuronal stress is transduced into mitochondrial oxidative stress and swelling is unclear. Recently, the aging determinant p66Shc that generates H2O2 reacting with cytochrome c and induces oxidation of PTP and mitochondrial swelling was found to be involved in MS and ALS. To investigate the role of p66Shc/PTP pathway in neurodegeneration, we performed experimental autoimmune encephalomyelitis (EAE) experiments in p66Shc knockout mice (p66Shc-/-), knock out mice for cyclophilin-D (Cyc-D-/-), and p66Shc Cyc-D double knock out (p66Shc/Cyc-D-/-) mice. Results confirm that deletion of p66Shc protects from EAE without affecting immune response, whereas it is not epistatic to the Cyc-D mutation. These findings demonstrate that p66Shc contributes to EAE induced neuronal damage most likely through the opening of PTP suggesting that p66Shc/PTP pathway transduces neurodegenerative stresses.


Assuntos
Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Degeneração Neural/metabolismo , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Animais , Apoptose , Linhagem Celular , Peptidil-Prolil Isomerase F , Ciclofilinas/deficiência , Ciclofilinas/metabolismo , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Ensaio de Imunoadsorção Enzimática , Deleção de Genes , Humanos , Camundongos , Camundongos Knockout , Poro de Transição de Permeabilidade Mitocondrial , Degeneração Neural/patologia , Neurônios/metabolismo , Neurônios/patologia , Ratos , Proteínas Adaptadoras da Sinalização Shc/deficiência , Medula Espinal/metabolismo , Medula Espinal/patologia , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src
15.
Tumori ; 99(6): 293e-8e, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24503807

RESUMO

A panel of experts from Italian Comprehensive Cancer Centers defines the recommendations for external quality control programs aimed to accreditation to excellence of these institutes. After definition of the process as a systematic, periodic evaluation performed by an external agency to verify whether a health organization possesses certain prerequisites regarding structural, organizational and operational conditions that are thought to affect health care quality, the panel reviews models internationally available and makes final recommendations on aspects considered of main interest. This position paper has been produced within a special project of the Ministry of Health of the Italian Government aimed to accredit, according to OECI model, 11 Italian cancer centers in the period 2012-2014. The Project represents the effort undertaken by this network of Comprehensive Cancer Centers to find a common denominator for the experience of all Institutes in external quality control programs. Fourteen shared "statements" are put forth, designed to offer some indications on the main aspects of this subject, based on literature evidence or expert opinions. They deal with the need for "accountability" and involvement of the entire organization, the effectiveness of self-evaluation, the temporal continuity and the educational value of the experience, the use of indicators and measurement tools, additionally for intra- and inter-organization comparison, the system of evaluation models used, the provision for specific requisites for oncology, and the opportunity for mutual exchange of evaluation experiences.


Assuntos
Acreditação , Benchmarking , Pesquisa Biomédica , Institutos de Câncer/normas , Qualidade da Assistência à Saúde , Pesquisa Biomédica/organização & administração , Pesquisa Biomédica/normas , Pesquisa Biomédica/tendências , Competência Clínica , Procedimentos Clínicos , Órgãos Governamentais , Pessoal de Saúde , Humanos , Capacitação em Serviço , Internacionalidade , Itália , Revisão por Pares , Controle de Qualidade , Pesquisadores , Responsabilidade Social
16.
Biochim Biophys Acta ; 1832(1): 114-20, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23046813

RESUMO

Although epigenetic drugs have been approved for use in selected malignancies, there is significant need for a better understanding of their mechanism of action. Here, we study the action of a clinically approved DNA-methyltransferase inhibitor - decitabine (DAC) - in acute myeloid leukemia (AML) cells. At low doses, DAC treatment induced apoptosis of NB4 Acute Promyelocytic Leukemia (APL) cells, which was associated with the activation of the extrinsic apoptotic pathway. Expression studies of the members of the Death Receptor family demonstrated that DAC induces the expression of TNF-related apoptosis-inducing ligand (TRAIL). Upregulation of TRAIL, upon DAC treatment, was associated with specific epigenetic modifications induced by DAC in the proximity of the TRAIL promoter, as demonstrated by DNA demethylation, increased DNaseI sensitivity and histone acetylation of a non-CpG island, CpG-rich region located 2kb upstream to the transcription start site. Luciferase assay experiments showed that this region behave as a DNA methylation sensitive transcriptional regulatory element. The CpG regulatory element was also found methylated in samples derived from APL patients. These findings have been confirmed in the non-APL, AML Kasumi cell line, suggesting that this regulatory mechanism may be extended to other AMLs. Our study suggests that DNA methylation is a regulatory mechanism relevant for silencing of the TRAIL apoptotic pathway in leukemic cells, and further elucidates the mechanism by which epigenetic drugs mediate their anti-leukemic effects.


Assuntos
Apoptose/efeitos dos fármacos , Azacitidina/análogos & derivados , Inibidores de Histona Desacetilases/farmacologia , Leucemia Mieloide Aguda/fisiopatologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Azacitidina/farmacologia , Linhagem Celular Tumoral , Metilação de DNA/efeitos dos fármacos , Decitabina , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Regiões Promotoras Genéticas , Transdução de Sinais/efeitos dos fármacos , Ligante Indutor de Apoptose Relacionado a TNF/genética
17.
Curr Pharm Des ; 19(15): 2708-14, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23092318

RESUMO

Reactive oxygen species (ROS) are regarded as hazardous by-products of mitochondrial respiration. In addition to the respiratory chain, specific ROS-generating systems have evolved. In particular, p66Shc is a mitochondrial redox protein that oxidizes cytochrome c to generate H2O2. Consistently, the deletion of p66Shc in cells and tissue results in reduced levels of ROS and oxidative stress. Taking advantage of the p66Shc knock out (p66KO) mouse model of decreased ROS production, we assessed the role of endogenously-produced ROS in tumorigenesis. Spontaneous tumor incidence was investigated and found unaltered in two different strains, 129Sv and C57Bl/6J, p66KO mice. In addition, papilloma formation upon exposure to ultraviolet radiation (UV) or 7,12-Dimethylbenz(a)anthracene/12-O-tetradecanoylphorbol- 13-acetate (DMBA/TPA) was found to be slightly lower in the absence of p66Shc. The role of p66Shc in tumorigenesis was also investigated in the absence of the tumor suppressor gene p53 (p53KO) by generating p53-p66Shc double knock out (DKO) mice. Notably, DKO mice displayed a significantly increased lifespan compared to p53KO mice. In addition, 2-deoxy-2-(18F)fluoro-D-glucose Positron Emission Tomography ([18F]FDG PET) analysis allowed to determine that disease onset occurred later in life in DKO mice compared to p53KO and that a low percentage of these mice did not develop tumors. Overall, these results indicate that although tumor incidence is not decreased in p66KO mice, p66Shc contributes to tumor initiation, in particular upon activation by carcinogens as well as when p53- mediated tumor suppression mechanisms defect.


Assuntos
Apoptose , Transformação Celular Neoplásica , Estresse Oxidativo , Proteínas Adaptadoras da Sinalização Shc/fisiologia , Proteína Supressora de Tumor p53/fisiologia , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Carcinógenos/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Acetato de Tetradecanoilforbol/toxicidade , Raios Ultravioleta
18.
Blood ; 120(22): 4391-9, 2012 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-23033271

RESUMO

Although intrinsic apoptosis defects are causal to the extended survival of chronic lymphocytic leukemia (CLL) B cells, several lines of evidence support a contribution of the peripheral lymphoid organs and BM microenvironment to the extended lifespan of leukemic B cells. Lymphocyte trafficking is controlled by homing signals provided by stromal cell-derived chemokines and egress signals provided by sphingosine-1-phosphate (S1P). In the present study, we show that expression of S1P1, the S1P receptor responsible for lymphocyte egress, is selectively reduced in CLL B cells with unmutated IGHV. Expression of S1P2, which controls B-cell homeostasis, is also impaired in CLL B cells but independently of the IGHV mutational status. We provide evidence herein that p66Shc, a Shc adaptor family member the deficiency of which is implicated in the apoptosis defects of CLL B cells, controls S1P1 expression through its pro-oxidant activity. p66Shc also controls the expression of the homing receptor CCR7, which opposes S1P1 by promoting lymphocyte retention in peripheral lymphoid organs. The results of the present study provide insights into the regulation of S1P1 expression in B cells and suggest that defective egress caused by impaired S1P1 expression contributes to the extended survival of CLL B cells by prolonging their residency in the prosurvival niche of peripheral lymphoid organs.


Assuntos
Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Receptores de Lisoesfingolipídeo/genética , Proteínas Adaptadoras da Sinalização Shc/fisiologia , Adulto , Animais , Feminino , Regulação da Expressão Gênica/genética , Regulação Leucêmica da Expressão Gênica , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Camundongos , Camundongos Knockout , Oxidantes/metabolismo , Prognóstico , Receptores de Lisoesfingolipídeo/fisiologia , Proteínas Adaptadoras da Sinalização Shc/genética , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Células Tumorais Cultivadas
19.
Aging Cell ; 10(1): 55-65, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21040401

RESUMO

Longevity of a p66Shc knockout strain (ShcP) was previously attributed to increased stress resistance and altered mitochondria. Microarrays of ShcP tissues indicated alterations in insulin signaling. Consistent with this observation, ShcP mice were more insulin sensitive and glucose tolerant at organismal and tissue levels, as was a novel p66Shc knockout (ShcL). Increasing and decreasing Shc expression in cell lines decreased and increased insulin sensitivity, respectively - consistent with p66Shc's function as a repressor of insulin signaling. However, differences between the two p66Shc knockout strains were also observed. ShcL mice were fatter and susceptible to fatty diets, and their fat was more insulin sensitive than controls. On the other hand, ShcP mice were leaner and resisted fatty diets, and their adipose was less insulin sensitive than controls. ShcL and ShcP strains are both highly inbred on the C57Bl/6 background, so we investigated gene expression at the Shc locus, which encodes three isoforms, p66, p52, and p46. Isoform p66 is absent in both strains; thus, the remaining difference to which to attribute the 'lean' phenotype is expression of the other two isoforms. ShcL mice have a precise deletion of p66Shc and normal expression of p52 and p46Shc isoforms in all tissues; thus, a simple deletion of p66Shc results in a 'fat' phenotype. However, ShcP mice in addition to p66Shc deletion have a fourfold increase in p46Shc expression in white fat. Thus, p46Shc overexpression in fat, rather than p66Shc deletion, is the likely cause of decreased adiposity and reduced insulin sensitivity in the fat of ShcP mice, which has implications for the longevity of the strain.


Assuntos
Adiposidade/genética , Insulina/metabolismo , Isoformas de Proteínas/genética , Proteínas Adaptadoras da Sinalização Shc/genética , Transdução de Sinais/fisiologia , Animais , Células Cultivadas , Gorduras na Dieta/metabolismo , Feminino , Loci Gênicos/fisiologia , Glucose/metabolismo , Resistência à Insulina/genética , Longevidade/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo/genética , Isoformas de Proteínas/metabolismo , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Magreza/genética , Magreza/metabolismo
20.
Am J Cardiol ; 106(10): 1443-9, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21059434

RESUMO

In patients with ST-segment elevation acute myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI), abrupt reperfusion can induce myocardial injury and apoptotic cell death. Reperfusion-induced myocardial damage, however, cannot be easily evaluated in clinical practice because of the lack of specific biomarkers. Cytochrome c, a mitochondrial protein, is released on reperfusion into the cytosol, where it triggers the apoptotic process. It can reach the external fluid and circulating blood when cell rupture occurs. We measured the cytochrome c circulating levels in patients with STEMI undergoing pPCI, and correlated them with the clinical signs of myocardial necrosis and reperfusion. The plasma creatine kinase-MB mass and serum cytochrome c (enzyme-linked immunosorbent assay method) were serially measured in 55 patients with STEMI undergoing pPCI. The angiographic and electrocardiographic signs of myocardial reperfusion were also assessed. Cytochrome c transiently increased in all patients with STEMI, with a curve that paralleled that of creatine kinase-MB. A significant relation was found between the peak values of the 2 biomarkers (R = 0.35, p = 0.01) and between the areas under the 2 curves (R = 0.33, p = 0.02). The creatine kinase-MB peak value correlated significantly with the clinical features of infarct extension. In contrast, the cytochrome c peak value correlated inversely with the myocardial blush grade. Patients with clinical signs of myocardial reperfusion injury had a significantly greater cytochrome c peak value than patients without reperfusion injury (median 1.65 ng/ml, interquartile range 1.20 to 2.20, vs 1.1 ng/ml, interquartile range 0.65 to 1.55; p = 0.04). In conclusion, serum cytochrome c is detectable in the early phase of STEMI treated with pPCI and is associated with clinical signs of impaired myocardial reperfusion.


Assuntos
Angioplastia Coronária com Balão , Citocromos c/sangue , Infarto do Miocárdio/sangue , Infarto do Miocárdio/terapia , Traumatismo por Reperfusão Miocárdica/sangue , Idoso , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Estudos Prospectivos
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