RESUMO
Primary central nervous system lymphoma (PCNSL) is confined to the brain, eyes, and cerebrospinal fluid without evidence of systemic spread. Rarely, PCNSL occurs in the context of immunosuppression (eg, posttransplant lymphoproliferative disorders or HIV [AIDS-related PCNSL]). These cases are poorly characterized, have dismal outcome, and are typically Epstein-Barr virus (EBV)-associated (ie, tissue-positive). We used targeted sequencing and digital multiplex gene expression to compare the genetic landscape and tumor microenvironment (TME) of 91 PCNSL tissues all with diffuse large B-cell lymphoma histology. Forty-seven were EBV tissue-negative: 45 EBV- HIV- PCNSL and 2 EBV- HIV+ PCNSL; and 44 were EBV tissue-positive: 23 EBV+ HIV+ PCNSL and 21 EBV+ HIV- PCNSL. As with prior studies, EBV- HIV- PCNSL had frequent MYD88, CD79B, and PIM1 mutations, and enrichment for the activated B-cell (ABC) cell-of-origin subtype. In contrast, these mutations were absent in all EBV tissue-positive cases and ABC frequency was low. Furthermore, copy number loss in HLA class I/II and antigen-presenting/processing genes were rarely observed, indicating retained antigen presentation. To counter this, EBV+ HIV- PCNSL had a tolerogenic TME with elevated macrophage and immune-checkpoint gene expression, whereas AIDS-related PCNSL had low CD4 gene counts. EBV-associated PCNSL in the immunosuppressed is immunobiologically distinct from EBV- HIV- PCNSL, and, despite expressing an immunogenic virus, retains the ability to present EBV antigens. Results provide a framework for targeted treatment.
Assuntos
Neoplasias do Sistema Nervoso Central/etiologia , Neoplasias do Sistema Nervoso Central/imunologia , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/imunologia , Linfoma/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Nervoso Central/genética , Neoplasias do Sistema Nervoso Central/virologia , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Feminino , Herpesvirus Humano 4/isolamento & purificação , Humanos , Tolerância Imunológica , Linfoma/etiologia , Masculino , Pessoa de Meia-Idade , Mutação , Transcriptoma , Microambiente TumoralRESUMO
Idiopathic pulmonary fibrosis (IPF) is a severe and often fatal disease. Diagnosis of IPF requires considerable expertise and experience. Since publication of the international IPF guideline in the year 2011 and Update 2018 several studies and technical advances occurred, which made a new assessment of the diagnostic process mandatory. In view of the antifibrotic drugs which have been approved for the treatment of IPF patients, the goal of this guideline is to foster early, confident and effective diagnosis of IPF. The guideline focusses on the typical clinical setting of an IPF patient and provides tools to exclude known causes of interstitial lung disease including standardised questionnaires, serologic testing and cellular analysis of bronchoalveolar lavage. High resolution computed tomography remains crucial in the diagnostic work-up.âIf it is necessary to obtain specimen for histology transbronchial lung cryobiopsy is the primary approach, while surgical lung biopsy is reserved for patients who are fit for it and in whom bronchoscopic diagnosis did not provide the information needed. Despite considerable progress, IPF remains a diagnosis of exclusion and multidisciplinary discussion remains the golden standard of diagnosis.
Assuntos
Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/terapia , Pulmão/diagnóstico por imagem , Guias de Prática Clínica como Assunto , Biópsia , Humanos , Fibrose Pulmonar Idiopática/patologia , Pulmão/patologia , Doenças Pulmonares Intersticiais , Tomografia Computadorizada por Raios XRESUMO
The WHO Classification of Lung Tumors (2015) established the use of immunohistochemical stainings for resection specimens, however, detailed recommendations had been missing. Now, an international expert panel has summarized key questions for daily routine practice and provided recommendations to assist the community in the appropriate use of immunohistochemistry in this context. This article provides an overview of the most important aspects.
Assuntos
Imunofenotipagem/métodos , Neoplasias Pulmonares , Humanos , Imuno-HistoquímicaRESUMO
Fibrosing lung diseases describe a heterogeneous group of interstitial lung diseases (ILD) of highly variable etiology, but with a unifying terminal process of irreversible, fibroproliterative destruction of the alveolar surface, loss of compliance and progressive impairment of gas exchange. In view of the heterogeneity, the disastrous prognoses in some cases and the treatment consequences, a thorough differential diagnosis is essential in all patients. Antifibrotic therapies are currently only indicated in idiopathic pulmonary fibrosis (IPF). The only curative therapeutic option is lung transplantation. Therefore, suitable patients should be promptly evaluated.
Assuntos
Fibrose Pulmonar Idiopática/diagnóstico por imagem , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Fibrose Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Diagnóstico Diferencial , Humanos , Pulmão , PrognósticoRESUMO
The new concept of spread through air spaces (STAS) was introduced for pulmonary adenocarcinomas in the 2015 WHO classification for lung cancer. Yet, available data demonstrate that STAS is of high prognostic impact and associated with specific clinic-pathological characteristics. This article provides a comprehensive overview of recent developments in this field.
Assuntos
Neoplasias Pulmonares , Inoculação de Neoplasia , Humanos , Invasividade Neoplásica , PrognósticoRESUMO
Recently a new TNM classification for tumors of the lung was published, encompassing some relevant changes, for example how to deal with multiple lung tumors. This article comprehensively describes respective changes. Furthermore, background information on how the new TNM classification was built and what should be done in the future to further improve prognosis and outcome prediction is reviewed.
Assuntos
Neoplasias Pulmonares/classificação , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias/métodos , Humanos , Pulmão/patologia , Linfonodos/patologia , Gradação de Tumores , Neoplasias Primárias Múltiplas/patologia , PrognósticoRESUMO
Multifocal neuroendocrine lung tumour is a rare diagnosis. Multiple lung foci of different sizes are usually apparent on chest CT scans. It is assumed that multifocal neuroendocrine lung tumours originally develop from diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH). This results in cell aggregations formed by proliferation of neuroendocrine cells that are already physiologically present in the bronchial system. If these cell proliferations break through the bronchial basement membrane, they are considered to constitute tumourlets if they measure ≤ 5 mm and carcinoid tumours if they are larger than 5 mm. The speed of proliferation of the cell hyperplasias appears to vary. Many of the patients are completely asymptomatic, the multifocal neuroendocrine lung tumours being diagnosed by chance. However, other patients complain of breathlessness, reduced physical capacity and cough. There may also be reduction of lung function. In these cases, chest HRCT often reveals peribronchial fibrosis or bronchiectasis in addition to the lung foci. Bronchoscopy is usually not helpful. Surgical lung biopsy is considered to be the diagnostic gold standard. Histological examination typically shows a mixture of cell hyperplasias, tumourlets and carcinoid tumours. There is no consensus on the treatment of multifocal neuroendocrine tumours. Taking the clinical situation and the chest HRCT findings as our starting point, we developed a stepwise approach that is guided by the success of the individual therapeutic procedures. The most favourable prognosis is found in affected people without clinical symptoms whose lung foci all measure less than 5 mm. In these cases the 5-year survival rate is over 90%.
Assuntos
Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/terapia , Diagnóstico Diferencial , Medicina Baseada em Evidências , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Primárias Múltiplas , Tumores Neuroendócrinos/patologia , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Resultado do TratamentoRESUMO
Interstitial lung diseases (ILDs) comprise a number of rare entities with an estimated incidence of 10-25 per 100,000 inhabitants but the incidence greatly increases beyond the age of 65 years. The prognosis depends on the underlying cause. The fibrotic disorders show a set of radiological and histopathological patterns that are distinct but not entirely specific. In the absence of a clear clinical picture and consistent high resolution computed tomography (HRCT) findings, patients are advised to undergo surgical lung biopsies from two or three lung lobes (or transbronchial biopsies) to determine the histopathological pattern. The ILDs are differentiated into disorders of known causes (e.g. collagen vascular disease, drug-related), idiopathic interstitial pneumonia (IIP), granulomatous ILDs (e.g. sarcoidosis) and other forms of ILD (e.g. Langerhans' cell histiocytosis). The IIPs encompass idiopathic pulmonary fibrosis (IPF), non-specific interstitial pneumonia, desquamative interstitial pneumonia, respiratory bronchiolitis-interstitial lung disease, cryptogen organizing pneumonia, lymphocytic interstitial pneumonia and acute interstitial pneumonia. Additionally, a category of unclassified interstitial pneumonia exists. The pathologist has to recognize and address the histopathological pattern. In a multidisciplinary discussion the disorder is allocated to a clinicopathological entity and the histopathological pattern plays a major role in the classification of the entity. Recognition of the underlying pattern and the respective histopathological differential diagnoses is important as the therapy varies depending on the cause and ranges from elimination of the stimulus (if possible) to antifibrotic drug therapy up to preparation for lung transplantation.
Assuntos
Doenças Pulmonares Intersticiais/patologia , Pulmão/patologia , Fatores Etários , Idoso , Biópsia , Estudos Transversais , Diagnóstico Diferencial , Europa (Continente) , Humanos , Doenças Pulmonares Intersticiais/classificação , Doenças Pulmonares Intersticiais/epidemiologia , Sociedades Médicas , Tomografia Computadorizada por Raios X , Estados UnidosRESUMO
BACKGROUND: Endothelial thrombomodulin (TM) is critically involved in anticoagulation, anti-inflammation, cytoprotection and normal fetal development. Tumor necrosis factor alpha (TNFα) suppresses TM expression. OBJECTIVE: TNFα has been shown to down-regulate TM partly via activation of nuclear factor kappa B (NF-κB). However, because the TM promoter lacks an NF-κB binding site, the direct involvement of NF-κB has been controversial. We investigated the role of the upstream regulatory serine kinase, inhibitory kappa-B kinase-ß (IKKß), in TM expression and function with or without TNFα treatment. METHODS: Inhibition of IKKß was achieved by specific chemical inhibitors, siRNA or shRNA. TM expression was assessed by qRT-PCR, Western blot, flow cytometry, luciferase reporter assay and chromatin immune-precipitation (ChIP) assay. TM function was estimated by generation of activated protein C (APC). NF-κB activation was determined by immunocytochemistry. RESULTS AND CONCLUSIONS: IKKß inhibition increased TM expression and function, and attenuated TNFα-mediated TM down-regulation. In contrast, inhibition of downstream canonical NF-κB protein family members p50 and p65 (RelA) failed to up-regulate TM expression and did not affect IKKß inhibition-mediated TM over-expression. However, knockdown of cRel and RelB, family members of the canonical and non-canonical NF-κB pathway, respectively, resulted in TM over-expression. IKKß inhibition caused over-expression, increased promoter activity and enhanced binding of Krüppel-like factor 2 (Klf2) to the TM promoter, which positively regulates TM expression. Finally, knockdown of Klf2 completely attenuated IKKß inhibition-mediated TM up-regulation. We conclude that IKKß regulates TM in a Klf2-dependent manner.
Assuntos
Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Quinase I-kappa B/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , NF-kappa B/metabolismo , Trombomodulina/metabolismo , Anti-Inflamatórios/química , Anticoagulantes/química , Sítios de Ligação , Imunoprecipitação da Cromatina , Regulação para Baixo , Citometria de Fluxo , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Proteína C/metabolismo , RNA Interferente Pequeno/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
A unique subpopulation of peripheral blood mononuclear cells that exhibit a parallel expression of haematopoietic and mesenchymal markers has been described as "circulating fibrocytes". These cells were demonstrated to obtain a fibroblastic phenotype in tissues or cell culture and contribute to pulmonary fibrotic disorders and tissue remodelling processes. The aim of our study was to characterise the recruitment of circulating fibrocytes in vivo in the model of chronic hypoxic pulmonary hypertension in mice and to analyse the therapeutic effect of the stable prostacyclin analogue trepostinil with respect to this cell population. To track circulating fibrocytes in vivo, we transplanted wild-type mice with bone marrow from ubiquitously eGFP expressing mice and subjected them to chronic hypoxia. We observed significantly increased recruitment of circulating fibrocytes to the remodelled pulmonary resistance arteries in response to hypoxia. Treatment with treprostinil significantly reduced the recruitment of these cells compared to normoxic mice. Treprostinil also reduced right ventricular systolic pressure and slightly reduced the vascular remodelling but failed to reverse the right ventricular hypertrophy. In summary, we show that circulating fibrocytes contribute to hypoxic pulmonary vascular remodelling and may be specifically targeted by a prostacyclin analogue. Further investigations of cellular and paracrine mechanisms are warranted to decipher their role in pulmonary hypertension.
Assuntos
Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/farmacocinética , Anti-Hipertensivos/uso terapêutico , Epoprostenol/análogos & derivados , Fibroblastos/efeitos dos fármacos , Hipertensão Pulmonar/tratamento farmacológico , Leucócitos Mononucleares/efeitos dos fármacos , Animais , Circulação Sanguínea , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/fisiopatologia , Células da Medula Óssea/efeitos dos fármacos , Quimerismo , Doença Crônica , Epoprostenol/farmacologia , Epoprostenol/uso terapêutico , Feminino , Humanos , Hipertensão Pulmonar/sangue , Hipertensão Pulmonar/fisiopatologia , Hipertrofia Ventricular Direita/tratamento farmacológico , Hipertrofia Ventricular Direita/fisiopatologia , Hipóxia/fisiopatologia , Pulmão/irrigação sanguínea , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiopatologia , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/fisiopatologiaRESUMO
Although increasing numbers of patients suffer from chronic destructive lung diseases, there are no effective therapeutic options apart from transplantation. Understanding the mechanisms of physiological and regenerative alveolar septation is prerequisite for the development of regenerative therapies for the lung. We compared lung gene expression in the phase of induction of post-natal and post-pneumonectomy alveolarisation to identify regulatory genes involved in both processes. We performed genome-wide microarray screenings of newborn and pneumonectomised mouse lungs 1 and 3 days after birth or surgery. Selected candidates were validated by real-time PCR, Western blot and in situ hybridisation. We found 58 genes to be regulated in both models with 40 candidates being changed likewise. Many of these genes participated in growth and differentiation processes. Additionally, immune system, structural molecules, respiratory chain, signal transduction and metabolism were involved. Some candidates were not yet linked to specific functions. The highest regulatory concordance was observed for various isoforms of (pro-)collagen molecules, elastin and the elastin-associated protein fibrillin1 being corporately upregulated. Our findings do not definitively support a common regulating mechanism for induction of post-natal and adult alveolarisation, but some candidates in the intersection of both models are promising for further investigations.
Assuntos
Perfilação da Expressão Gênica , Regeneração Hepática/genética , Pulmão/crescimento & desenvolvimento , Pneumonectomia , Proteínas de Fase Aguda/genética , Animais , Animais Recém-Nascidos , Western Blotting , Elastina/genética , Elastina/metabolismo , Fibrilina-1 , Fibrilinas , Genes fos , Humanos , Hibridização In Situ , Lipocalina-2 , Lipocalinas/genética , Masculino , Camundongos , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Oncogênicas/genética , Reação em Cadeia da Polimerase , Pró-Colágeno/genética , Pró-Colágeno/metabolismo , Regulação para CimaAssuntos
Transtornos Hemorrágicos/etiologia , Neoplasias/complicações , Paraproteinemias/sangue , Amiloidose/sangue , Amiloidose/complicações , Inibidores da Angiogênese/uso terapêutico , Animais , Fatores de Coagulação Sanguínea/antagonistas & inibidores , Fatores de Coagulação Sanguínea/fisiologia , Fibrinólise , Hemorragia/etiologia , Hemorragia/terapia , Transtornos Hemorrágicos/sangue , Transtornos Hemorrágicos/terapia , Técnicas Hemostáticas , Humanos , Neoplasias/sangue , Paraproteinemias/etiologia , Troca Plasmática , Ratos , Trombocitopenia/etiologia , Macroglobulinemia de Waldenstrom/sangue , Macroglobulinemia de Waldenstrom/complicaçõesRESUMO
MicroRNAs (miRNAs) are potent RNA regulators of gene expression. Some viruses encode miRNAs, most of unknown function. The majority of viral miRNAs are not conserved, and whether any have conserved functions remains unclear. Here, we report that two human polyomaviruses associated with serious disease in immunocompromised individuals, JC virus and BK virus, encode miRNAs with the same function as that of the monkey polyomavirus simian virus 40 miRNAs. These miRNAs are expressed late during infection to autoregulate early gene expression. We show that the miRNAs generated from both arms of the pre-miRNA hairpin are active at directing the cleavage of the early mRNAs. This finding suggests that despite multiple differences in the miRNA seed regions, the primary target (the early mRNAs) and function (the downregulation of early gene expression) are evolutionarily conserved among the primate polyomavirus-encoded miRNAs. Furthermore, we show that these miRNAs are expressed in individuals diagnosed with polyomavirus-associated disease, suggesting their potential as targets for therapeutic intervention.
Assuntos
Vírus BK/genética , Evolução Molecular , Vírus JC/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Animais , Sequência de Bases , Encéfalo/patologia , Encéfalo/fisiologia , Encéfalo/virologia , Linhagem Celular , Simulação por Computador , Haplorrinos , Humanos , MicroRNAs/química , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/metabolismo , Precursores de RNA/química , Precursores de RNA/genética , Precursores de RNA/metabolismo , RNA Viral/química , Alinhamento de Sequência , Vírus 40 dos Símios/genética , Viroses/genéticaRESUMO
The lipid-lowering agents, statins, are the most commonly prescribed class of drugs in the western world. Because of their widespread use, many patients undergo surgical procedures while on statins. Statins, in addition to cholesterol-lowering effects, also have anticoagulant, immunosuppressive, and antiproliferative properties that may affect the risk of local wound complications. This study investigated the relationship between statins and postoperative wound complications in a large cohort of patients undergoing inguinal or ventral hernia repair. Data mining was performed in the Veterans Integrated Service Network (VISN)16 Data Warehouse. This database contains clinical and demographic information about all veterans cared for at the ten VA Medical Centers that comprise the South Central VA Healthcare Network in the mid-south region of the US. Aggregate data (age, body mass index, smoking history, gender, race, history of diabetes, statin use, and postoperative wound complications) were obtained for all patients who underwent inguinal or ventral hernia repair during the period October 1, 1996-November 30, 2004. During the period of the query, 10,782 patients (10,676 male, 106 female), 1,242 (11.5%) of whom received statins, underwent herniorrhaphy. Statin use did not affect the risk of wound infection or delayed wound healing. Statin use was, however, associated with an increased rate of local postoperative bleeding complications (P=0.01). When the type of hernia, age, smoking, diabetes, and body mass index were included in a multivariate analysis, statins remained borderline significant as an independent predictor of wound hematoma/postoperative bleeding (P=0.04), odds ratio 1.6 (95% CI 1.03-2.44). Patients who undergo inguinal herniorrhaphy while on statins have an increased risk of postoperative wound hematoma/hemorrhage. Focus on additional factors that may affect the propensity to postoperative bleeding and on meticulous intraoperative hemostasis are particularly important in such patients.
Assuntos
Hematoma/epidemiologia , Hematoma/etiologia , Hérnia Inguinal/cirurgia , Hérnia Ventral/cirurgia , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Complicações Pós-Operatórias , Sistema de Registros , Fumar/epidemiologia , Estados Unidos/epidemiologia , Veteranos/estatística & dados numéricosRESUMO
Gene therapy aimed at the respiratory epithelium holds therapeutic potential for diseases such as cystic fibrosis and lung cancer. Polyethylenimine (PEI) has been utilized for gene delivery to the airways. In this study, we describe a new modification of PEI, in which an oligopeptide related to the protein transduction domain of HIV-1 TAT was covalently coupled to 25 kDa PEI (PEI) through a heterobifunctional polyethylenglycol (PEG) spacer resulting in a TAT-PEG-PEI conjugate. Improved DNA reporter gene complexation and protection was observed for small (approximately 90 nm) polyplexes as well as significantly improved stability against polyanions, Alveofact, bronchial alveolar lining fluid and DNase. To determine polyplex toxicity in vitro, MTT assays were performed and, for in vivo testing, the mice bronchial alveolar lavage was investigated for total cell counts, quantity of neutrophils, total protein and TNF-alpha concentration. All parameters suggest significantly lower toxicity for TAT-PEG-PEI. Transfection efficiencies of both PEI and TAT-PEG-PEI polyplexes with DNA were studied under in vitro conditions (A549) and in mice after intratracheal instillation. While luciferase expression in A549 cells was much lower for TAT-PEG-PEI (0.2 ng/mg protein) than for PEI (2 ng/mg), significantly higher transfection efficiencies for TAT-PEG-PEI were detected in mice. Reporter gene expression was distributed through bronchial and alveolar tissue. Thus, TAT-PEG-PEI represents a new approach to non-viral gene carriers for lung therapy, comprising protection for plasmid DNA, low toxicity and significantly enhanced transfection efficiency under in vivo conditions.
Assuntos
DNA/administração & dosagem , Portadores de Fármacos , Produtos do Gene tat/química , Terapia Genética/métodos , Nanoestruturas , Polietilenoglicóis/química , Polietilenoimina/química , Animais , Líquido da Lavagem Broncoalveolar/química , Fenômenos Químicos , Físico-Química , Sistemas de Liberação de Medicamentos , Células Epiteliais/fisiologia , Etídio/química , Produtos do Gene tat/toxicidade , Genes Reporter/genética , Heparina/química , Humanos , Luciferases/genética , Pulmão/citologia , Pulmão/patologia , Camundongos , Ensaios de Proteção de Nucleases , Oligonucleotídeos/administração & dosagem , Distribuição Tecidual , TransfecçãoRESUMO
OBJECTIVES: The choice of biomedical samples for microarray gene expression studies is decisive for both validity and interpretability of results. We present a consistent, comprehensive framework to deal with the typical selection problems in microarray studies. METHODS: Microarray studies are designed either as case-control studies or as comparisons of parallel groups from cohort studies, since high levels of random variation in the experimental approach thwart absolute measurements of gene expression levels. Validity and results of gene expression studies heavily rely on the appropriate choice of these study groups. Therefore, the so-called principles of comparability, which are well known from both clinical and epidemiological studies, need to be applied to microarray experiments. RESULTS: The principles of comparability are the study-base principle, the principle of deconfounding and the principle of comparable accuracy in measurements. We explain each of these principles, show how they apply to microarray experiments, and illustrate them with examples. The examples are chosen as to represent typical stumbling blocks of microarray experimental design, and to exemplify the benefits of implementing the principles of comparability in the setting of microarray experiments. CONCLUSIONS: Microarray studies are closely related to classical study designs and therefore have to obey the same principles of comparability as these. Their validity should not be compromised by selection, confounding or information bias. The so-called study-base principle, calling for comparability and thorough definition of the compared cell populations, is the key principle for the choice of biomedical samples and controls in microarray studies.
Assuntos
Perfilação da Expressão Gênica/métodos , Computação Matemática , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Algoritmos , Animais , Humanos , Modelos Genéticos , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Reprodutibilidade dos Testes , Viés de SeleçãoRESUMO
BACKGROUND: The small bowel is a dose-limiting normal tissue in radiation therapy of malignancies in the abdomen and pelvis, as well as an important determinant of survival after non-therapeutic radiation exposure. Irradiation of normal tissues, including intestine, causes loss of vascular thromboresistance and upregulation of thrombin receptors. Radiation-induced endothelial dysfunction is thought to be involved in both early and delayed radiation responses. Hence, thrombin may be a potential target for ameliorating normal tissue radiation toxicity. OBJECTIVE: To assess direct thrombin inhibition as a protective strategy against small bowel radiation toxicity. METHODS: Rat small intestine was exposed to localized orthovoltage X-radiation. Recombinant hirudin, a direct thrombin inhibitor, or vehicle was infused from 2 days before irradiation to 14 days after irradiation. Structural, cellular, and molecular aspects of intestinal radiation injury were assessed at 2 weeks (early toxicity) and 26 weeks (chronic toxicity) after irradiation. RESULTS: Compared with unirradiated intestine, irradiated intestine showed increased expression of tissue factor, increased immunoreactivity for enzymatically active thrombin, and increased extravascular fibrin(ogen) deposition. Hirudin treatment significantly attenuated radiation-induced mucosal damage (P = 0.04), reactive intestinal wall thickening (P = 0.02), transforming growth factor-beta immunoreactivity levels (P = 0.0002), and collagen III deposition (P = 0.003). The differences between hirudin-treated and control rats were more pronounced at 2 weeks than at 26 weeks after irradiation. Hirudin treatment did not affect postradiation granulocyte infiltration. CONCLUSIONS: Short-term thrombin inhibition attenuates important aspects of intestinal radiation toxicity. Thrombin is a promising target for minimizing normal tissue injury after radiation therapy of cancer, as well as for protecting normal tissues from the adverse effects of non-therapeutic radiation exposure.
Assuntos
Raios gama/efeitos adversos , Hirudinas/farmacologia , Enteropatias/tratamento farmacológico , Intestinos/efeitos da radiação , Tolerância a Radiação/efeitos dos fármacos , Animais , Fibrina/análise , Fibrina/genética , Enteropatias/etiologia , Enteropatias/patologia , Intestinos/química , Intestinos/patologia , Masculino , RNA Mensageiro/análise , Lesões por Radiação/tratamento farmacológico , Protetores contra Radiação/farmacologia , Ratos , Ratos Sprague-Dawley , Trombina/análise , Trombina/antagonistas & inibidores , Trombina/genética , Tromboplastina/análise , Tromboplastina/genéticaRESUMO
Estrogen treatment in symptomatic postmenopausal women appears to improve cognitive performance including memory, an effect which may involve enhanced nitric oxide formation in hippocampal neurons. To study whether 17beta-estradiol (E2) affects NO synthase activity in the hippocampus, we investigated the influence of E2 on hippocampal NO synthase expression and activity in female rats. Ovariectomy, which significantly decreased E2 serum levels, reduced neuronal (nNOS) and endothelial NO synthase (eNOS) expression and Ca(2+)-dependent NOS activity. E2 substitution reversed these effects. It is concluded that E2 increases nNOS and eNOS expression and activity in female hippocampus and thus improves hippocampal function.
Assuntos
Estradiol/farmacologia , Hipocampo/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Animais , Estradiol/metabolismo , Feminino , Hipocampo/metabolismo , Masculino , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo III , Ovariectomia , Ratos , Ratos Endogâmicos WKY , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologiaRESUMO
Cancer and increased age are risk factors for coagulation activation. Patients with advanced prostate cancer, which usually presents in the seventh to eighth decade of life, are likely to be at increased risk for thrombosis. We report results of a controlled study of changes in specific and sensitive markers of coagulation activation in patients with prostate cancer. Complete blood count, prothrombin time, partial thromboplastin time, prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin complex (TAT) and quantitative D-dimers (DD) were measured in 30 patients of advanced prostate cancer (androgen ablated), in 30 newly diagnosed localized prostate cancer patients, in 30 healthy age-matched volunteers, and in 20 healthy young volunteers. Plasma F1 + 2 (P < 0.05) and DD (P < 0.05), but not TAT, were significantly elevated in healthy elderly males (mean age, 77 years) when compared with healthy young volunteers (mean age, 35 years). F1 + 2, TAT and DD were significantly elevated in advanced prostate cancer when compared with healthy age-matched controls (P < 0.001). In conclusion, advanced prostate cancer patients have significantly increased levels of sensitive markers of coagulation activation compared with healthy age-matched controls. This data can be used to plan studies to determine the risk of clinically significant coagulopathy and the role of primary prophylaxis in patients with advanced prostate cancer.
Assuntos
Coagulação Sanguínea , Neoplasias da Próstata/sangue , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antitrombina III , Biomarcadores/sangue , Estudos de Casos e Controles , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Peptídeo Hidrolases/sangue , Protrombina , Trombofilia/sangue , Trombofilia/diagnóstico , Trombofilia/etiologiaRESUMO
Thromboembolism is not uncommon in multiple myeloma (MM) patients on treatment, but its pathogenesis remains poorly understood. We report the results of a prospective randomized trial of 62 newly diagnosed MM patients tested at baseline for hypercoagulability and treated with intensive chemotherapy with or without thalidomide in a randomized fashion. During the induction phase, 12 patients (19%) developed evidence of deep venous thrombosis (DVT), which was significantly more common in the thalidomide arm (36%) than in the control group (3%) (P = 0.001). Fourteen patients (23%) were found to have a baseline-reduced response to activated protein C (APC) in the absence of factor V Leiden mutation. Using a Kaplan-Meier analysis, a significantly higher proportion of patients with APC resistance developed DVT (5/14 versus 7/38; P = 0.04) irrespective of thalidomide administration. The risk of DVT was highest (50%) in patients with APC resistance on thalidomide. None of the patients with normal APC response and not receiving thalidomide developed DVT. In conclusion, in this series, acquired APC resistance was present in almost one-quarter of newly diagnosed myeloma patients and significantly increased the risk of DVT.