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1.
J Immunother Cancer ; 11(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37045474

RESUMO

BACKGROUND: Chimeric antigen receptor (CAR)-T cell-based immunotherapy constitutes a revolutionary advance for treatment of relapsed/refractory hematological malignancies. Nevertheless, cytokine release and immune effector cell-associated neurotoxicity syndromes are life-threatening toxicities in which the endothelium could be a pathophysiological substrate. Furthermore, differential diagnosis from sepsis, highly incident in these patients, is challenging. Suitable laboratory tools could be determinant for their appropriate management. METHODS: Sixty-two patients treated with CAR-T cell immunotherapy for hematological malignancies (n=46 with CD19-positive diseases, n=16 with multiple myeloma) were included. Plasma samples were obtained: before CAR-T cell infusion (baseline); after 24-48 hours; at suspicion of any toxicity onset and 24-48 hours after immunomodulatory treatment. Biomarkers of endothelial dysfunction (soluble vascular cell adhesion molecule 1 (sVCAM-1), soluble TNF receptor 1 (sTNFRI), thrombomodulin (TM), soluble suppression of tumorigenesis-2 factor (ST2), angiopoietin-2 (Ang-2)), innate immunity activation (neutrophil extracellular traps (NETs), soluble C5b-9 (sC5b-9)) and hemostasis/fibrinolysis (von Willebrand Factor antigen (VWF:Ag), ADAMTS-13 (A13), α2-antiplasmin (α2-AP), plasminogen activator inhibitor-1 antigen (PAI-1 Ag)) were measured and compared with those in cohorts of patients with sepsis and healthy donors. RESULTS: Patients who developed CAR-T cell toxicities presented increased levels of sVCAM-1, sTNFRI and ST2 at the clinical onset versus postinfusion values. Twenty-four hours after infusion, ST2 levels were good predictors of any CAR-T cell toxicity, and combination of ST2, Ang-2 and NETs differentiated patients requiring intensive care unit admission from those with milder clinical presentations. Association of Ang-2, NETs, sC5b-9, VWF:Ag and PAI-1 Ag showed excellent discrimination between severe CAR-T cell toxicities and sepsis. CONCLUSIONS: This study provides relevant contributions to the current knowledge of the CAR-T cell toxicities pathophysiology. Markers of endotheliopathy, innate immunity activation and hemostatic imbalance appear as potential laboratory tools for their prediction, severity and differential diagnosis.


Assuntos
Neoplasias Hematológicas , Hemostáticos , Sepse , Humanos , Linfócitos T , Fator de von Willebrand , Diagnóstico Diferencial , Inibidor 1 de Ativador de Plasminogênio , Proteína 1 Semelhante a Receptor de Interleucina-1 , Hemostasia , Neoplasias Hematológicas/terapia
2.
Sci Rep ; 13(1): 5665, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024714

RESUMO

Purkinje cell (PC) loss occurs at an early age in patients and animal models of Niemann-Pick Type C (NPC), a lysosomal storage disease caused by mutations in the Npc1 or Npc2 genes. Although degeneration of PCs occurs early in NPC, little is known about how NPC1 deficiency affects the postnatal development of PCs. Using the Npc1nmf164 mouse model, we found that NPC1 deficiency significantly affected the postnatal development of PC dendrites and synapses. The developing dendrites of Npc1nmf164 PCs were significantly deficient in mitochondria and lysosomes. Furthermore, anabolic (mTORC1) and catabolic (TFEB) signaling pathways were not only perturbed but simultaneously activated in NPC1-deficient PCs, suggesting a loss of metabolic balance. We also found that mice with conditional heterozygous deletion of the Phosphatase and Tensin Homolog Deleted on Chromosome 10 gene (Pten-cHet), an inhibitor of mTORC1, showed similar early dendritic alterations in PCs to those found in Npc1-deficient mice. However, in contrast to Npc1nmf164 mice, Pten-cHet mice exhibited the overactivation of the mTORC1 pathway but with a strong inhibition of TFEB signaling, along with no dendritic mitochondrial reductions by the end of their postnatal development. Our data suggest that disruption of the lysosomal-metabolic signaling in PCs causes dendritic and synaptic developmental deficits that precede and promote their early degeneration in NPC.


Assuntos
Doença de Niemann-Pick Tipo C , Células de Purkinje , Camundongos , Animais , Células de Purkinje/metabolismo , Doença de Niemann-Pick Tipo C/genética , Doença de Niemann-Pick Tipo C/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Modelos Animais de Doenças , Lisossomos/metabolismo
3.
Expert Rev Respir Med ; 16(11-12): 1237-1245, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36351310

RESUMO

OBJECTIVE: We compared dexmedetomidine-remifentanil vs. propofol-remifentanil in terms of safety and quality during sedation for Endobronchial ultrasonography (EBUS). METHODS: A randomized, double-blind trial. Outpatients undergoing EBUS randomly received 1 µg/kg/hour dexmedetomidine or a target concentration of 2.5 µg/mL propofol, both combined with remifentanil initially targeted at 1.5 ng/mL and subsequently titrated. Additional sedatives were restricted. The primary outcome was the need for airway rescue interventions to treat oxygen desaturation. RESULTS: Twenty-eight patients received dexmedetomidine-remifentanil and 27 received propofol-remifentanil. Airway rescue interventions were fewer in the dexmedetomidine group vs. the propofol one (23 vs. 76% patients, relative risk 3.21 (95% CI 1.55-6.64, P < 0.002)). Desaturation in the dexmedetomidine group was always resolved by increasing nasal oxygen flow, whereas additional interventions were needed in 60% of patients receiving propofol. Hypotension was more frequent in the propofol group, while hypertension, bradycardia and coughing were similar in both. Bronchoscopists' and patients' satisfaction were similar, although in the dexmedetomidine group two patients needed additional sedatives and two patients would not repeat the sedation technique. CONCLUSION: Moderate sedation with dexmedetomidine-remifentanil for EBUS is safer than deep sedation with propofol-remifentanil but it would occasionally need additional sedatives to ensure patient satisfaction.


Assuntos
Sedação Profunda , Dexmedetomidina , Propofol , Humanos , Propofol/efeitos adversos , Remifentanil/efeitos adversos , Dexmedetomidina/efeitos adversos , Sedação Consciente/métodos , Hipnóticos e Sedativos , Oxigênio , Método Duplo-Cego
4.
Am J Obstet Gynecol ; 227(2): 277.e1-277.e16, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35351411

RESUMO

BACKGROUND: COVID-19 presents a spectrum of signs and symptoms in pregnant women that might resemble preeclampsia. Differentiation between severe COVID-19 and preeclampsia is difficult in some cases. OBJECTIVE: To study biomarkers of endothelial damage, coagulation, innate immune response, and angiogenesis in preeclampsia and COVID-19 in pregnancy in addition to in vitro alterations in endothelial cells exposed to sera from pregnant women with preeclampsia and COVID-19. STUDY DESIGN: Plasma and sera samples were obtained from pregnant women with COVID-19 infection classified into mild (n=10) or severe (n=9) and from women with normotensive pregnancies as controls (n=10) and patients with preeclampsia (n=13). A panel of plasmatic biomarkers was assessed, including vascular cell adhesion molecule-1, soluble tumor necrosis factor-receptor I, heparan sulfate, von Willebrand factor antigen (activity and multimeric pattern), α2-antiplasmin, C5b9, neutrophil extracellular traps, placental growth factor, soluble fms-like tyrosine kinase-1, and angiopoietin 2. In addition, microvascular endothelial cells were exposed to patients' sera, and changes in the cell expression of intercellular adhesion molecule 1 on cell membranes and von Willebrand factor release to the extracellular matrix were evaluated through immunofluorescence. Changes in inflammation cell signaling pathways were also assessed by of p38 mitogen-activated protein kinase phosphorylation. Statistical analysis included univariate and multivariate methods. RESULTS: Biomarker profiles of patients with mild COVID-19 were similar to those of controls. Both preeclampsia and severe COVID-19 showed significant alterations in most circulating biomarkers with distinctive profiles. Whereas severe COVID-19 exhibited higher concentrations of vascular cell adhesion molecule-1, soluble tumor necrosis factor-α receptor I, heparan sulfate, von Willebrand factor antigen, and neutrophil extracellular traps, with a significant reduction of placental growth factor compared with controls, preeclampsia presented a marked increase in vascular cell adhesion molecule-1 and soluble tumor necrosis factor-α receptor I (significantly increased compared with controls and patients with severe COVID-19), with a striking reduction in von Willebrand factor antigen, von Willebrand factor activity, and α2-antiplasmin. As expected, reduced placental growth factor, increased soluble fms-like tyrosine kinase-1 and angiopoietin 2, and a very high soluble fms-like tyrosine kinase-1 to placental growth factor ratio were also observed in preeclampsia. In addition, a significant increase in C5b9 and neutrophil extracellular traps was also detected in preeclampsia compared with controls. Principal component analysis demonstrated a clear separation between patients with preeclampsia and the other groups (first and second components explained 42.2% and 13.5% of the variance), mainly differentiated by variables related to von Willebrand factor, soluble tumor necrosis factor-receptor I, heparan sulfate, and soluble fms-like tyrosine kinase-1. Von Willebrand factor multimeric analysis revealed the absence of von Willebrand factor high-molecular-weight multimers in preeclampsia (similar profile to von Willebrand disease type 2A), whereas in healthy pregnancies and COVID-19 patients, von Willebrand factor multimeric pattern was normal. Sera from both preeclampsia and severe COVID-19 patients induced an overexpression of intercellular adhesion molecule 1 and von Willebrand factor in endothelial cells in culture compared with controls. However, the effect of preeclampsia was less pronounced than the that of severe COVID-19. Immunoblots of lysates from endothelial cells exposed to mild and severe COVID-19 and preeclampsia sera showed an increase in p38 mitogen-activated protein kinase phosphorylation. Patients with severe COVID-19 and preeclampsia were statistically different from controls, suggesting that both severe COVID-19 and preeclampsia sera can activate inflammatory signaling pathways. CONCLUSION: Although similar in in vitro endothelial dysfunction, preeclampsia and severe COVID-19 exhibit distinctive profiles of circulating biomarkers related to endothelial damage, coagulopathy, and angiogenic imbalance that could aid in the differential diagnosis of these entities.


Assuntos
Biomarcadores , COVID-19 , Pré-Eclâmpsia , Angiopoietina-2 , Biomarcadores/sangue , COVID-19/diagnóstico , Células Endoteliais , Feminino , Heparitina Sulfato , Humanos , Molécula 1 de Adesão Intercelular , Fator de Crescimento Placentário , Pré-Eclâmpsia/diagnóstico , Gravidez , Fator de Necrose Tumoral alfa , Molécula 1 de Adesão de Célula Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Proteínas Quinases p38 Ativadas por Mitógeno , Fator de von Willebrand
5.
Bone Marrow Transplant ; 57(5): 721-728, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35184147

RESUMO

Engraftment syndrome (ES) is a common complication after autologous hematopoietic cell transplantation (auto-HCT) whose pathophysiological substrate remains unclear. We investigated whether endothelial damage could contribute to ES. Circulating ECs-damage biomarkers were measured in plasma from patients with (ES; n = 14) or without ES (non-ES; n = 20), collected at different time points: before HCT, 5 (S5) and 10 days (S10) after HCT, and at either the ES onset (SON) or the discharge day (SDIS). Also, cultured endothelial cells (ECs) were exposed to serum samples, obtained at the same points, to evaluate changes in ECs-activation (ICAM-1, VE-Cadherin) biomarkers, the reactivity of ECs towards leukocytes, and activation of intracellular signaling proteins related to inflammation (p38MAPK) and proliferation (Erk1/2). Results showed that circulating VWF, sTNFR1 and sVCAM-1 levels were higher in ES patients at all the points assessed, especially at SON. In vitro results showed an increased ICAM-1 expression on ECs exposed to ES samples vs. non-ES samples, especially to S5, with elevated leukocyte adhesion. Also, a lower VE-Cadherin expression and an increased phosphorylation of p38MAPK and Erk1/2 proteins were observed in ECs exposed to ES vs. non-ES samples. Our results indicate that endothelial activation precedes ES development and could be one of its pathophysiological substrates.


Assuntos
Doenças Hematológicas , Transplante de Células-Tronco Hematopoéticas , Doenças do Sistema Imunitário , Biomarcadores/metabolismo , Células Endoteliais/metabolismo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Molécula 1 de Adesão Intercelular , Fenótipo
6.
Sensors (Basel) ; 20(11)2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32485791

RESUMO

Low-Power Wide-Area Network (LPWAN) is one of the enabling technologies of the Internet of Things (IoT), and focuses on providing long distance connectivity for a vast amount of smart devices. Currently, LoRa is one of the leading LPWAN solutions available for public use. In LPWANs, especially in LoRa, security is a major concern due to the resource constraints of the devices, the sensitivity level of the transmitted data, the large amount of connected devices, among other reasons. This paper studies the key management mechanism of LoRaWAN environments. A secure architecture for key management based on smart contracts and permissioned blockchain to enhance security and availability in LoRaWAN networks is proposed. To demonstrate the feasibility of the proposed blockchain-based LoRaWAN architecture, a working prototype has been created using open-source tools and commodity hardware. Performance analysis shows that the prototype presents similar execution time and latency values, when compared to a traditional system, especially for small and medium-sized LoRaWAN networks. We also discuss why the proposed solution can be used in environments with a large number of end-devices.

7.
Artigo em Português | LILACS | ID: biblio-1358861

RESUMO

RESUMO: A pré-eclâmpsia, uma complicação frequente da gravidez, é uma das principais causas maternas de morbidade e da mortalidade perinatal. Um grande avanço na classificação da pré-eclâmpsia foi a sua subdivisão em variantes precoces (<34 semanas de gestação) e tardias. Apesar de apresentarem maior prevalência no período gestacional, o aparecimento dessas intercorrências em período pós-parto e puerperal não deve ser negligenciado tendo em vista a sua importância clínica. Este artigo é um relato de caso de pré-eclâmpsia tardia em uma paciente de 37 anos, puérpera, que deu entrada no serviço de emergência hospitalar com quadro de edema agudo de pulmão, dispneia, estado torporoso e cianose periférica. O diagnóstico foi possível através de aferição de pressão arterial sistêmica e dosagem de proteinúria de 24h, tendo sido descartadas outras complicações possíveis após outros exames laboratoriais. O quadro foi estabilizado com uso de nitroprussiato de sódio e uso de pressão positiva contínua nas vias aéreas (do inglês: continuous positive airway pressure­CPAP) para correção de cianose. Logo depois do diagnóstico de pré-eclâmpsia, foi adicionado à prescrição o sulfato de magnésio para profilaxia de eclâmpsia. Após sete dias de internação sem demais intercorrências, a paciente recebeu alta. (AU)


ABSTRACT: Preeclampsia, a frequent complication of pregnancy, is a leading cause of maternal and perinatal morbidity and mortality. A major advance in the classification of preeclampsia was its subdivision into early- (<34 weeks of gestation) and late-onset variants. Although they present a higher prevalence in the gestational period, the appearance of these intercurrences in the postpartum and puerperal period should not be neglected given their clinical importance. It is described a case of late preeclampsia: a 37-year-old patient, at the postpartum period, who went to emergency service after being dyspneic, torporous, peripheral cyanosis, and with pulmonary edema. The diagnosis was made not only based on the medical signs and patient-reported symptoms, but also after laboratory findings such as 24h proteinuria and blood pressure measure. Other diagnoses, as HELLP Syndrome, were excluded after normal laboratory results. Her clinical condition was made stable after being medicated with sodium nitroprusside and using a continuous positive airway pressure (CPAP) for cyanosis correction. After the preeclampsia diagnosis, at another medical center, it was added to the prescription magnesium sulfate as an eclâmpsia prophylaxis. After the seventh day of admission, without other complications, the patient was discharged from the hospital. (AU)


Assuntos
Humanos , Feminino , Gravidez , Adulto , Pré-Eclâmpsia , Período Pós-Parto , Mortalidade Perinatal
9.
Evid. odontol. clín ; 3(2): 65-72, jul.-dic. 2017.
Artigo em Espanhol | LILACS | ID: biblio-999888

RESUMO

El patrón facial indica la dirección del crecimiento de la cara en sentido vertical u horizontal y este crecimiento se ve incrementado en la etapa de la dentición decidua, por lo que podría influir en la presencia de espacios primates. Además, el patrón de crecimiento que se manifiesta en las primeras etapas de vida se mantiene a lo largo de esta, que sumado a la presencia o no de espacios primates en la dentición decidua, nos ayudaría a predecir futuros apiñamientos en el sector anterior de la dentición permanente. La presente revisión de literatura nació a partir de la inquietud sobre la posible relación que existe entre el patrón facial y los espacios primates. No se encontraron estudios que relacionen ambas variables, sin embargo, el patrón facial en niños, así como las características principales de la dentición decidua ha sido ampliamente estudiados a nivel internacional y nacional. (AU)


Assuntos
Humanos , Assimetria Facial , Face , Crescimento
10.
J Emerg Trauma Shock ; 10(2): 60-63, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28367009

RESUMO

BACKGROUND: Due to the high incidence of thromboembolic events (deep venous thrombosis [DVT] and pulmonary embolus [PE]) after injury, many trauma centers perform lower extremity surveillance duplex ultrasounds. We hypothesize that trauma patients are at a higher risk of upper extremity DVTs (UEDVTs) than lower extremity DVTs (LEDVTs), and therefore, all extremities should be evaluated. MATERIALS AND METHODS: A retrospective chart and trauma registry review of Intensive Care Unit trauma patients with upper and LEDVTs detected on surveillance duplex ultrasound from January 2010 to December 2014 was carried out. Variables reviewed were age, gender, injury severity score, injury mechanism, clot location, day of clot detection, presence of central venous pressure catheter, presence of inferior vena cava filter, mechanical ventilation, and fracture. RESULTS: A total of 136 patients had a DVT in a 5-year period: upper - 71 (52.2%), lower - 61 (44.9%), both upper and lower - 4 (2.9%). Overall, 75 (55.2%) patients had a UEDVT. Upper DVT vein: Brachial (62), axillary (26), subclavian (11), and internal jugular (10). Lower DVT vein: femoral (58), popliteal (14), below knee (4), and iliac (2). 10.3% had a PE: UEDVT - 5 (6.7%) and LEDVT - 9 (14.8%) P = 0.159. CONCLUSIONS: The majority of the DVTs in the study were in the upper extremities. For trauma centers that aggressively screen the lower extremities with venous duplex ultrasound, surveillance to include the upper extremities is warranted.

11.
J Vis Exp ; (106): e52879, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26710000

RESUMO

Although targeted therapies are initially effective, resistance inevitably emerges. Several methods, such as genetic analysis of resistant clinical specimens, have been applied to uncover these resistance mechanisms to facilitate follow-up care. Although these approaches have led to clinically relevant discoveries, difficulties in attaining the relevant patient material or in deconvoluting the genomic data collected from these specimens have severely hampered the path towards a cure. To this end, we here describe a tool for expeditious discovery that may guide improvement in first-line therapies and alternative clinical management strategies. By coupling preclinical in vitro or in vivo drug selection with next-generation sequencing, it is possible to identify genomic structural variations and/or gene expression alterations that may serve as functional drivers of resistance. This approach facilitates the spontaneous emergence of alterations, enhancing the probability that these mechanisms may be observed in the patients. In this protocol we provide guidelines to maximize the potential for uncovering single nucleotide variants that drive resistance using adherent lines.


Assuntos
Resistência a Medicamentos/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Células HCT116 , Humanos , Técnicas In Vitro , Terapia de Alvo Molecular
12.
Hum Mutat ; 36(4): E2423-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25703262

RESUMO

Oncotator is a tool for annotating genomic point mutations and short nucleotide insertions/deletions (indels) with variant- and gene-centric information relevant to cancer researchers. This information is drawn from 14 different publicly available resources that have been pooled and indexed, and we provide an extensible framework to add additional data sources. Annotations linked to variants range from basic information, such as gene names and functional classification (e.g. missense), to cancer-specific data from resources such as the Catalogue of Somatic Mutations in Cancer (COSMIC), the Cancer Gene Census, and The Cancer Genome Atlas (TCGA). For local use, Oncotator is freely available as a python module hosted on Github (https://github.com/broadinstitute/oncotator). Furthermore, Oncotator is also available as a web service and web application at http://www.broadinstitute.org/oncotator/.


Assuntos
Bases de Dados Genéticas , Neoplasias/genética , Biologia Computacional/métodos , Variação Genética , Genômica/métodos , Humanos , Internet , Neoplasias/diagnóstico , Neoplasias/metabolismo , Navegador
13.
Sensors (Basel) ; 15(1): 2104-36, 2015 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-25608215

RESUMO

Due to their increasing dissemination, wireless sensor networks (WSNs) have become the target of more and more sophisticated attacks, even capable of circumventing both attack detection and prevention mechanisms. This may cause WSN users, who totally trust these security mechanisms, to think that a sensor reading is secure, even when an adversary has corrupted it. For that reason, a scheme capable of estimating the security level (SL) that these mechanisms provide to sensor data is needed, so that users can be aware of the actual security state of this data and can make better decisions on its use. However, existing security estimation schemes proposed for WSNs fully ignore detection mechanisms and analyze solely the security provided by prevention mechanisms. In this context, this work presents the sensor data security estimator (SDSE), a new comprehensive security estimation scheme for WSNs. SDSE is designed for estimating the sensor data security level based on security metrics that analyze both attack prevention and detection mechanisms. In order to validate our proposed scheme, we have carried out extensive simulations that show the high accuracy of SDSE estimates.


Assuntos
Redes de Comunicação de Computadores , Segurança Computacional , Tecnologia sem Fio , Algoritmos , Probabilidade
14.
J Proteome Res ; 13(11): 4676-85, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25227318

RESUMO

Deficient chloride transport through cystic fibrosis (CF) transmembrane conductance regulator (CFTR) causes lethal complications in CF patients. CF is the most common autosomal recessive genetic disease, which is caused by mutations in the CFTR gene; thus, CFTR mutants can serve as primary targets for drugs to modulate and rescue the ion channel's function. The first step of drug modulation is to increase the expression of CFTR in the apical plasma membrane (PM); thus, accurate measurement of CFTR in the PM is desired. This work reports a tandem enrichment strategy to prepare PM CFTR and uses a stable isotope labeled CFTR sample as the quantitation reference to measure the absolute amount of apical PM expression of CFTR in CFBE 41o- cells. It was found that CFBE 41o- cells expressing wild-type CFTR (wtCFTR), when cultured on plates, had 2.9 ng of the protein in the apical PM per million cells; this represented 10% of the total CFTR found in the cells. When these cells were polarized on filters, the apical PM expression of CFTR increased to 14%. Turnover of CFTR in the apical PM of baby hamster kidney cells overexpressing wtCFTR (BHK-wtCFTR) was also quantified by targeted proteomics based on multiple reaction monitoring mass spectrometry; wtCFTR had a half-life of 29.0 ± 2.5 h in the apical PM. This represents the first direct measurement of CFTR turnover using stable isotopes. The absolute quantitation and turnover measurements of CFTR in the apical PM can significantly facilitate understanding the disease mechanism of CF and thus the development of new disease-modifying drugs. Absolute CFTR quantitation allows for direct result comparisons among analyses, analysts, and laboratories and will greatly amplify the overall outcome of CF research and therapy.


Assuntos
Membrana Celular/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/tratamento farmacológico , Fibrose Cística/metabolismo , Modelos Moleculares , Proteômica/métodos , Animais , Biotinilação , Linhagem Celular , Cloretos/metabolismo , Cricetinae , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/química , Meia-Vida , Humanos , Transporte de Íons/fisiologia , Marcação por Isótopo , Espectrometria de Massas
15.
ACS Chem Biol ; 9(10): 2247-54, 2014 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-25058389

RESUMO

The small-molecule probes STF-31 and its analogue compound 146 were discovered while searching for compounds that kill VHL-deficient renal cell carcinoma cell lines selectively and have been reported to act via direct inhibition of the glucose transporter GLUT1. We profiled the sensitivity of 679 cancer cell lines to STF-31 and found that the pattern of response is tightly correlated with sensitivity to three different inhibitors of nicotinamide phosphoribosyltransferase (NAMPT). We also performed whole-exome next-generation sequencing of compound 146-resistant HCT116 clones and identified a recurrent NAMPT-H191R mutation. Ectopic expression of NAMPT-H191R conferred resistance to both STF-31 and compound 146 in cell lines. We further demonstrated that both STF-31 and compound 146 inhibit the enzymatic activity of NAMPT in a biochemical assay in vitro. Together, our cancer-cell profiling and genomic approaches identify NAMPT inhibition as a critical mechanism by which STF-31-like compounds inhibit cancer cells.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Citocinas/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Neoplasias/tratamento farmacológico , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Citocinas/genética , Citocinas/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores Enzimáticos/química , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Estrutura Molecular , Mutação/genética , Neoplasias/enzimologia , Neoplasias/patologia , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Bibliotecas de Moléculas Pequenas/química , Células Tumorais Cultivadas
16.
Nat Genet ; 45(12): 1483-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24185511

RESUMO

The diagnosed incidence of small intestine neuroendocrine tumors (SI-NETs) is increasing, and the underlying genomic mechanisms have not yet been defined. Using exome- and genome-sequence analysis of SI-NETs, we identified recurrent somatic mutations and deletions in CDKN1B, the cyclin-dependent kinase inhibitor gene, which encodes p27. We observed frameshift mutations of CDKN1B in 14 of 180 SI-NETs, and we detected hemizygous deletions encompassing CDKN1B in 7 out of 50 SI-NETs, nominating p27 as a tumor suppressor and implicating cell cycle dysregulation in the etiology of SI-NETs.


Assuntos
Inibidor de Quinase Dependente de Ciclina p27/genética , Neoplasias Intestinais/genética , Mutação , Tumores Neuroendócrinos/genética , Ciclo Celular/genética , Estudos de Coortes , Genes Supressores de Tumor , Predisposição Genética para Doença , Humanos , Neoplasias Intestinais/epidemiologia , Neoplasias Intestinais/patologia , Intestino Delgado/patologia , Tumores Neuroendócrinos/epidemiologia , Tumores Neuroendócrinos/patologia , Análise de Sequência de DNA
17.
Nature ; 499(7457): 214-218, 2013 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-23770567

RESUMO

Major international projects are underway that are aimed at creating a comprehensive catalogue of all the genes responsible for the initiation and progression of cancer. These studies involve the sequencing of matched tumour-normal samples followed by mathematical analysis to identify those genes in which mutations occur more frequently than expected by random chance. Here we describe a fundamental problem with cancer genome studies: as the sample size increases, the list of putatively significant genes produced by current analytical methods burgeons into the hundreds. The list includes many implausible genes (such as those encoding olfactory receptors and the muscle protein titin), suggesting extensive false-positive findings that overshadow true driver events. We show that this problem stems largely from mutational heterogeneity and provide a novel analytical methodology, MutSigCV, for resolving the problem. We apply MutSigCV to exome sequences from 3,083 tumour-normal pairs and discover extraordinary variation in mutation frequency and spectrum within cancer types, which sheds light on mutational processes and disease aetiology, and in mutation frequency across the genome, which is strongly correlated with DNA replication timing and also with transcriptional activity. By incorporating mutational heterogeneity into the analyses, MutSigCV is able to eliminate most of the apparent artefactual findings and enable the identification of genes truly associated with cancer.


Assuntos
Heterogeneidade Genética , Mutação/genética , Neoplasias/genética , Oncogenes/genética , Artefatos , Período de Replicação do DNA , Exoma/genética , Reações Falso-Positivas , Expressão Gênica , Genoma Humano/genética , Humanos , Neoplasias Pulmonares/genética , Taxa de Mutação , Neoplasias/classificação , Neoplasias/patologia , Neoplasias de Células Escamosas/genética , Reprodutibilidade dos Testes , Tamanho da Amostra
18.
Cell ; 153(3): 666-77, 2013 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-23622249

RESUMO

The analysis of exonic DNA from prostate cancers has identified recurrently mutated genes, but the spectrum of genome-wide alterations has not been profiled extensively in this disease. We sequenced the genomes of 57 prostate tumors and matched normal tissues to characterize somatic alterations and to study how they accumulate during oncogenesis and progression. By modeling the genesis of genomic rearrangements, we identified abundant DNA translocations and deletions that arise in a highly interdependent manner. This phenomenon, which we term "chromoplexy," frequently accounts for the dysregulation of prostate cancer genes and appears to disrupt multiple cancer genes coordinately. Our modeling suggests that chromoplexy may induce considerable genomic derangement over relatively few events in prostate cancer and other neoplasms, supporting a model of punctuated cancer evolution. By characterizing the clonal hierarchy of genomic lesions in prostate tumors, we charted a path of oncogenic events along which chromoplexy may drive prostate carcinogenesis.


Assuntos
Aberrações Cromossômicas , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Neoplasias da Próstata/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Estudos de Coortes , Estudo de Associação Genômica Ampla , Humanos , Masculino , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/patologia , Neoplasias da Próstata/patologia
19.
Nat Genet ; 45(5): 478-86, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23525077

RESUMO

The incidence of esophageal adenocarcinoma (EAC) has risen 600% over the last 30 years. With a 5-year survival rate of ~15%, the identification of new therapeutic targets for EAC is greatly important. We analyze the mutation spectra from whole-exome sequencing of 149 EAC tumor-normal pairs, 15 of which have also been subjected to whole-genome sequencing. We identify a mutational signature defined by a high prevalence of A>C transversions at AA dinucleotides. Statistical analysis of exome data identified 26 significantly mutated genes. Of these genes, five (TP53, CDKN2A, SMAD4, ARID1A and PIK3CA) have previously been implicated in EAC. The new significantly mutated genes include chromatin-modifying factors and candidate contributors SPG20, TLR4, ELMO1 and DOCK2. Functional analyses of EAC-derived mutations in ELMO1 identifies increased cellular invasion. Therefore, we suggest the potential activation of the RAC1 pathway as a contributor to EAC tumorigenesis.


Assuntos
Adenocarcinoma/genética , Biomarcadores Tumorais/genética , Neoplasias Esofágicas/genética , Exoma/genética , Genoma Humano/genética , Mutação/genética , Mapeamento Cromossômico , Rearranjo Gênico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Invasividade Neoplásica
20.
Nat Genet ; 45(3): 279-84, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23334666

RESUMO

Neuroblastoma is a malignancy of the developing sympathetic nervous system that often presents with widespread metastatic disease, resulting in survival rates of less than 50%. To determine the spectrum of somatic mutation in high-risk neuroblastoma, we studied 240 affected individuals (cases) using a combination of whole-exome, genome and transcriptome sequencing as part of the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) initiative. Here we report a low median exonic mutation frequency of 0.60 per Mb (0.48 nonsilent) and notably few recurrently mutated genes in these tumors. Genes with significant somatic mutation frequencies included ALK (9.2% of cases), PTPN11 (2.9%), ATRX (2.5%, and an additional 7.1% had focal deletions), MYCN (1.7%, causing a recurrent p.Pro44Leu alteration) and NRAS (0.83%). Rare, potentially pathogenic germline variants were significantly enriched in ALK, CHEK2, PINK1 and BARD1. The relative paucity of recurrent somatic mutations in neuroblastoma challenges current therapeutic strategies that rely on frequently altered oncogenic drivers.


Assuntos
Exoma , Mutação , Neuroblastoma , Linhagem Celular Tumoral , Predisposição Genética para Doença , Genoma Humano , Humanos , Neuroblastoma/genética , Neuroblastoma/fisiopatologia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Transcriptoma
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