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1.
Br J Anaesth ; 129(4): 612-623, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35820934

RESUMO

BACKGROUND: Tracheal intubation is a commonly performed procedure that can be associated with complications and result in patient harm. Videolaryngoscopy (VL) may decrease this risk as compared with Macintosh direct laryngoscopy (DL). This review evaluates the risk and benefit profile of VL compared with DL in adults. METHODS: We searched MEDLINE, Embase, CENTRAL, and Web of Science on February 27, 2021. We included RCTs comparing VL with DL in patients undergoing tracheal intubation in any setting. We separately compared outcomes according to VL design: Macintosh-style, hyperangulated, and channelled. RESULTS: A total of 222 RCTs (with 26 149 participants) were included. Most studies had unclear risk of bias in at least one domain, and all were at high risk of performance and detection bias. We found that videolaryngoscopes of any design likely reduce rates of failed intubation (Macintosh-style: risk ratio [RR]=0.41; 95% confidence interval [CI], 0.26-0.65; hyperangulated: RR=0.51; 95% CI, 0.34-0.76; channelled: RR=0.43, 95% CI, 0.30-0.61; moderate-certainty evidence) with increased rates of successful intubation on first attempt and better glottic views across patient groups and settings. Hyperangulated designs are likely favourable in terms of reducing the rate of oesophageal intubation, and result in improved rates of successful intubation in individuals presenting with difficult airway features (P=0.03). We also present other patient-oriented outcomes. CONCLUSIONS: In this systematic review and meta-analysis of trials of adults undergoing tracheal intubation, VL was associated with fewer failed attempts and complications such as hypoxaemia, whereas glottic views were improved. SYSTEMATIC REVIEW REGISTRATION: This article is based on a Cochrane Review published in the Cochrane Database of Systematic Reviews (CDSR) 2022, Issue 4, DOI: 10.1002/14651858.CD011136.pub3 (see www.cochranelibrary.com for information). Cochrane Reviews are regularly updated as new evidence emerges and in response to feedback, and the CDSR should be consulted for the most recent version of the review.


Assuntos
Laringoscópios , Laringoscopia , Adulto , Esôfago , Glote , Humanos , Intubação Intratraqueal/efeitos adversos , Intubação Intratraqueal/métodos , Laringoscopia/métodos
2.
Cochrane Database Syst Rev ; 4: CD011136, 2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35373840

RESUMO

BACKGROUND: Tracheal intubation is a common procedure performed to secure the airway in adults undergoing surgery or those who are critically ill. Intubation is sometimes associated with difficulties and complications that may result in patient harm. While it is traditionally achieved by performing direct laryngoscopy, the past three decades have seen the advent of rigid indirect videolaryngoscopes (VLs). A mounting body of evidence comparing the two approaches to tracheal intubation has been acquired over this period of time. This is an update of a Cochrane Review first published in 2016. OBJECTIVES: To assess whether use of different designs of VLs in adults requiring tracheal intubation reduces the failure rate compared with direct laryngoscopy, and assess the benefits and risks of these devices in selected population groups, users and settings. SEARCH METHODS: We searched MEDLINE, Embase, CENTRAL and Web of Science on 27 February 2021. We also searched clinical trials databases, conference proceedings and conducted forward and backward citation searches. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and quasi-RCTs with adults undergoing laryngoscopy performed with either a VL or a Macintosh direct laryngoscope (DL) in any clinical setting. We included parallel and cross-over study designs. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. We collected data for the following outcomes: failed intubation, hypoxaemia, successful first attempt at tracheal intubation, oesophageal intubation, dental trauma, Cormack-Lehane grade, and time for tracheal intubation. MAIN RESULTS: We included 222 studies (219 RCTs, three quasi-RCTs) with 26,149 participants undergoing tracheal intubation. Most studies recruited adults undergoing elective surgery requiring tracheal intubation. Twenty-one studies recruited participants with a known or predicted difficult airway, and an additional 25 studies simulated a difficult airway. Twenty-one studies were conducted outside the operating theatre environment; of these, six were in the prehospital setting, seven in the emergency department and eight in the intensive care unit.  We report here the findings of the three main comparisons according to videolaryngoscopy device type. We downgraded the certainty of the outcomes for imprecision, study limitations (e.g. high or unclear risks of bias), inconsistency when we noted substantial levels of statistical heterogeneity and publication bias. Macintosh-style videolaryngoscopy versus direct laryngoscopy (61 studies, 9883 participants) We found moderate-certainty evidence that a Macintosh-style VL probably reduces rates of failed intubation (risk ratio (RR) 0.41, 95% confidence interval (CI) 0.26 to 0.65; 41 studies, 4615 participants) and hypoxaemia (RR 0.72, 95% CI 0.52 to 0.99; 16 studies, 2127 participants). These devices may also increase rates of success on the first intubation attempt (RR 1.05, 95% CI 1.02 to 1.09; 42 studies, 7311 participants; low-certainty evidence) and probably improve glottic view when assessed as Cormack-Lehane grade 3 and 4 (RR 0.38, 95% CI 0.29 to 0.48; 38 studies, 4368 participants; moderate-certainty evidence). We found little or no clear difference in rates of oesophageal intubation (RR 0.51, 95% CI 0.22 to 1.21; 14 studies, 2404 participants) but this finding was supported by low-certainty evidence. We were unsure of the findings for dental trauma because the certainty of this evidence was very low (RR 0.68, 95% CI 0.16 to 2.89; 18 studies, 2297 participants). We were not able to pool data for time required for tracheal intubation owing to considerable heterogeneity (I2 = 96%). Hyperangulated videolaryngoscopy versus direct laryngoscopy (96 studies, 11,438 participants) We found moderate-certainty evidence that hyperangulated VLs probably reduce rates of failed intubation (RR 0.51, 95% CI 0.34 to 0.76; 63 studies, 7146 participants) and oesophageal intubation (RR 0.39, 95% CI 0.18 to 0.81; 14 studies, 1968 participants). In subgroup analysis, we noted that hyperangulated VLs were more likely to reduce failed intubation when used on known or predicted difficult airways (RR 0.29, 95% CI 0.17 to 0.48; P = 0.03 for subgroup differences; 15 studies, 1520 participants). We also found that these devices may increase rates of success on the first intubation attempt (RR 1.03, 95% CI 1.00 to 1.05; 66 studies, 8086 participants; low-certainty evidence) and the glottic view is probably also improved (RR 0.15, 95% CI 0.10 to 0.24; 54 studies, 6058 participants; data for Cormack-Lehane grade 3/4 views; moderate-certainty evidence). However, we found low-certainty evidence of little or no clear difference in rates of hypoxaemia (RR 0.49, 95% CI 0.22 to 1.11; 15 studies, 1691 participants), and the findings for dental trauma were unclear because the certainty of this evidence was very low (RR 0.51, 95% CI 0.16 to 1.59; 30 studies, 3497 participants). We were not able to pool data for time required for tracheal intubation owing to considerable heterogeneity (I2 = 99%). Channelled videolaryngoscopy versus direct laryngoscopy (73 studies, 7165 participants) We found moderate-certainty evidence that channelled VLs probably reduce rates of failed intubation (RR 0.43, 95% CI 0.30 to 0.61; 53 studies, 5367 participants) and hypoxaemia (RR 0.25, 95% CI 0.12 to 0.50; 15 studies, 1966 participants). They may also increase rates of success on the first intubation attempt (RR 1.10, 95% CI 1.05 to 1.15; 47 studies, 5210 participants; very low-certainty evidence) and probably improve glottic view (RR 0.14, 95% CI 0.09 to 0.21; 40 studies, 3955 participants; data for Cormack-Lehane grade 3/4 views; moderate-certainty evidence). We found little or no clear difference in rates of oesophageal intubation (RR 0.54, 95% CI 0.17 to 1.75; 16 studies, 1756 participants) but this was supported by low-certainty evidence. We were unsure of the findings for dental trauma because the certainty of the evidence was very low (RR 0.52, 95% CI 0.13 to 2.12; 29 studies, 2375 participants). We were not able to pool data for time required for tracheal intubation owing to considerable heterogeneity (I2 = 98%). AUTHORS' CONCLUSIONS: VLs of all designs likely reduce rates of failed intubation and result in higher rates of successful intubation on the first attempt with improved glottic views. Macintosh-style and channelled VLs likely reduce rates of hypoxaemic events, while hyperangulated VLs probably reduce rates of oesophageal intubation. We conclude that videolaryngoscopy likely provides a safer risk profile compared to direct laryngoscopy for all adults undergoing tracheal intubation.


Assuntos
Laringoscópios , Laringoscopia , Adulto , Estado Terminal , Humanos , Intubação Intratraqueal , Laringoscopia/métodos
3.
J Gen Virol ; 96(Pt 2): 351-359, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25381055

RESUMO

Several members of the family Circoviridae have been shown to encode proteins with apoptotic activity. For example, both porcine circovirus type 2 (PCV2) and chicken anemia virus (CAV) encode a third viral protein (VP3) that has been shown to be cytotoxic. Interestingly, in the case of the CAV protein (designated apoptin), apoptosis is specific to transformed cell types. Similarities in genome structure and organization suggest that PCV type 1 (PCV1) may also contain a third ORF, which codes for a protein with homologous activity. To investigate this, ORF prediction followed by gene expression analyses were conducted on a gene found to be homologous to CAV and PCV2 VP3. Our data presented herein elucidate a putative ORF3 that codes for a viral protein with functional similarity to that of apoptin and PCV2 VP3. Unlike its homologues, sequence analysis revealed a highly hydrophobic, extended C-terminal domain in PCV1 VP3, which harbours a strong nuclear export signal. Subcellular localization analysis demonstrated divergent PCV1 VP3 localization patterns compared with that of CAV VP3. Interestingly, cytotoxicity studies revealed evidence that apoptosis may be selective to transformed cell types, similar to apoptin; however, PCV1 VP3 induced a dramatic G1 cell cycle arrest as opposed to the G2/M arrest observed with apoptin. These results indicate that nuclear localization of PCV1 VP3 is necessary neither for induction of apoptosis nor for transformed cell selectivity, and suggest a mechanism of action distinct from that of apoptin.


Assuntos
Apoptose , Circovirus/fisiologia , Interações Hospedeiro-Patógeno , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Animais , Ciclo Celular , Linhagem Celular , Sobrevivência Celular , Perfilação da Expressão Gênica , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Suínos , Proteínas Virais/genética
4.
Adv Healthc Mater ; 13(3): e2301123, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37921265

RESUMO

Studies on gamma radiation-induced injury have long been focused on hematopoietic, gastrointestinal, and cardiovascular systems, yet little is known about the effects of gamma radiation on the function of human cortical tissue. The challenge in studying radiation-induced cortical injury is, in part, due to a lack of human tissue models and physiologically relevant readouts. Here, a physiologically relevant 3D collagen-based cortical tissue model (CTM) is developed for studying the functional response of human iPSC-derived neurons and astrocytes to a sub-lethal radiation exposure (5 Gy). Cytotoxicity, DNA damage, morphology, and extracellular electrophysiology are quantified. It is reported that 5 Gy exposure significantly increases cytotoxicity, DNA damage, and astrocyte reactivity while significantly decreasing neurite length and neuronal network activity. Additionally, it is found that clinically deployed radioprotectant amifostine ameliorates the DNA damage, cytotoxicity, and astrocyte reactivity. The CTM provides a critical experimental platform to understand cell-level mechanisms by which gamma radiation (GR) affects human cortical tissue and to screen prospective radioprotectant compounds.


Assuntos
Amifostina , Humanos , Raios gama , Estudos Prospectivos , Dano ao DNA , Neurônios
5.
Animals (Basel) ; 13(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37889720

RESUMO

Many bird species in Australia require tree hollows for breeding. However, assessing the benefits of urban nest boxes to native birds requires frequent monitoring that allows to assess nesting success. To better understand the benefits of nest boxes for native birds, we examined the impact of local habitat characteristics, invasive species (common myna, Acridotheres tristis), and native mammalian predators on urban nest box use and nesting success of native birds. We installed 216 nest boxes across nine locations in southeastern Australia (S.E. Queensland and northern New South Wales) in both long-invaded sites (invaded before 1970) and more recently invaded sites (after 1990). We monitored all boxes weekly over two breeding seasons. We recorded seven bird species and three mammal species using the nest boxes. Weekly box occupancy by all species averaged 8% of all boxes, with the species most frequently recorded in the nest boxes being the common brushtail possum (Trichosurus vulpecula), a native cavity user and nest predator. We recorded 137 nesting attempts in the boxes across all bird species. The most frequent nesting species were the invasive alien common mynas (72 nesting attempts). We recorded an average nesting failure rate of 53.3% for all bird species. We did not record any common mynas evicting other nesting birds, and found that several native species used the same box after the common myna completed its nesting. We recorded native possums in 92% of the boxes, and possum occupancy of boxes per site was negatively correlated with bird nesting success (p = 0.021). These results suggest that when boxes are accessible to invasive species and native predators, they are unlikely to significantly improve nesting opportunities for native birds. To ensure efficient use of limited conservation resources, nest boxes should be designed to target species of high conservation importance and limit other species of both predators and competitors.

6.
Cells ; 12(16)2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37626855

RESUMO

Cellular senescence is a durable cell cycle arrest as a result of the finite proliferative capacity of cells. Senescence responds to both intrinsic and extrinsic cellular stresses, such as aging, mitochondrial dysfunction, irradiation, and chemotherapy. Here, we report on the use of mass cytometry (MC) to analyze multiple model systems and demonstrate MC as a platform for senescence analysis at the single-cell level. We demonstrate changes to p16 expression, cell cycling fraction, and histone tail modifications in several established senescent model systems and using isolated human T cells. In bone marrow mesenchymal stromal cells (BMSCs), we show increased p16 expression with subsequent passage as well as a reduction in cycling cells and open chromatin marks. In WI-38 cells, we demonstrate increased p16 expression with both culture-induced senescence and oxidative stress-induced senescence (OSIS). We also use Wanderlust, a trajectory analysis tool, to demonstrate how p16 expression changes with histone tail modifications and cell cycle proteins. Finally, we demonstrate that repetitive stimulation of human T cells with CD3/CD28 beads induces an exhausted phenotype with increased p16 expression. This p16-expressing population exhibited higher expression of exhaustion markers such as EOMES and TOX. This work demonstrates that MC is a useful platform for studying senescence at a single-cell protein level, and is capable of measuring multiple markers of senescence at once with high confidence, thereby improving our understanding of senescent pathways.


Assuntos
Histonas , Pesquisa , Humanos , Envelhecimento , Antígenos CD28 , Ciclo Celular
7.
Lancet Planet Health ; 5(11): e840-e850, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34774124

RESUMO

The ongoing COVID-19 pandemic, caused by zoonotic SARS-CoV-2, has important links to biodiversity loss and ecosystem health. These links range from anthropogenic activities driving zoonotic disease emergence and extend to the pandemic affecting biodiversity conservation, environmental policy, ecosystem services, and multiple conservation facets. Crucially, such effects can exacerbate the initial drivers, resulting in feedback loops that are likely to promote future zoonotic disease outbreaks. We explore these feedback loops and relationships, highlighting known and potential zoonotic disease emergence drivers (eg, land-use change, intensive livestock production, wildlife trade, and climate change), and discuss direct and indirect effects of the ongoing pandemic on biodiversity loss and ecosystem health. We stress that responses to COVID-19 must include actions aimed at safeguarding biodiversity and ecosystems, in order to avoid future emergence of zoonoses and prevent their wide-ranging effects on human health, economies, and society. Such responses would benefit from adopting a One Health approach, enhancing cross-sector, transboundary communication, as well as from collaboration among multiple actors, promoting planetary and human health.


Assuntos
COVID-19 , Ecossistema , Pandemias , Animais , Biodiversidade , COVID-19/epidemiologia , Humanos
8.
Curr Hematol Malig Rep ; 15(4): 316-332, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32529515

RESUMO

PURPOSE OF REVIEW: Peripheral T cell lymphomas (PTCLs) are a heterogeneous group of diseases and represent approximately 10-15% of all non-Hodgkin lymphomas. Multiagent chemotherapy with a CHOP (cyclophosphamide, adriamycin, vincristine, prednisone)-like regimen is the current standard of care in the frontline setting, but outcomes for PTCL patients generally remain poor. Strategies used to improve survival and reduce the risk of relapse in PTCL patients include autologous hematopoietic cell transplant (autoHCT) and allogeneic HCT (alloHCT). Due to the relative rarity of these diseases, the evidence supporting the use of autoHCT and alloHCT is based on retrospective and single-arm prospective studies. Novel targeted therapies are now being incorporated into the treatment of PTCL, and they may play important roles in improving upon current standards of care. Herein, we summarize the evidence supporting HCT for the treatment of the most common PTCL histologic subtypes and highlight novel treatment strategies aimed at improving outcomes for these patients, including cutting-edge approaches using chimeric antigen receptor T cells (CAR-T). RECENT FINDINGS: Given recent improvements in OS and PFS in CD30+ PTCL using the drug-antibody conjugate brentuximab vedotin (BV), new questions arise regarding the impact of BV on consolidative autoHCT, and its role as a maintenance therapy. Multiple histone deacetylase inhibitors (HDACis) have been approved for the treatment of relapsed/refractory PTCL, and these agents are being incorporated into HCT approaches, both in the frontline and maintenance settings. Early data incorporating these agents into novel conditioning regimens have been reported, and emerging evidence from recent trials suggests that CART cell therapies may prove effective in relapsed/refractory PTCL. The recommended treatment strategy in non-ALK+ PTCL remains induction with a CHOP-like regimen followed by consolidative autoHCT in first remission. In the relapsed/refractory setting, salvage chemotherapy followed by HCT (autoHCT or alloHCT depending on histologic subtype and HCT history) offers the only potential for cure or long-term remission. Ample room for improvement remains in the treatment of patients with PTCL, and novel treatment strategies incorporating targeted agents and CAR-T therapy may help to address the unmet needs of this patient population.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Imunoterapia Adotiva , Linfoma de Células T Periférico/terapia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/transplante , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Brentuximab Vedotin/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/mortalidade , Quimioterapia de Indução , Linfoma de Células T Periférico/genética , Linfoma de Células T Periférico/imunologia , Linfoma de Células T Periférico/mortalidade , Terapia de Salvação , Linfócitos T/imunologia , Transplante Autólogo , Resultado do Tratamento
9.
Clin Cancer Res ; 14(21): 6963-73, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18980991

RESUMO

PURPOSE: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, gefitinib and erlotinib, lead to significant tumor regressions in 10% to 15% of non-small cell lung cancer (NSCLC) patients with EGFR activating mutations. However, 30% to 40% of NSCLC patients, majority of whom are EGFR wild-type, develop stable disease following EGFR tyrosine kinase inhibitor therapy. EGFR-directed antibodies (cetuximab) are effective treatments for head and neck squamous cell carcinomas, which seldom contain EGFR mutations. The determinant(s) of efficacy of EGFR-targeted therapies in EGFR wild-type cancers is not well defined. EXPERIMENTAL DESIGN: We examined the relationship of EGFR ligands, EGF, transforming growth factor-alpha,and amphiregulin and the efficacy of gefitinib and cetuximab in EGFR wild-type NSCLC (n=10) and head and neck squamous cell carcinoma (n=4) cell lines. We compared amphiregulin expression using immunohistochemistry in EGFR wild-type NSCLC patients (n=24) that developed either stable or progressive disease following erlotinib or gefitinib treatment. RESULTS: Cell lines which produced >or=20 pmol/L amphiregulin, as detected by an ELISA, were significantly more likely to be growth inhibited by both gefitinib and cetuximab than those that produced minimal or no amphiregulin. In these cell lines, both cetuximab and gefitinib led to cell cycle arrest at the G(1)-S boundary and was associated with preferential inhibition of extracellular signal-regulated kinase 1/2 but not Akt signaling. Amphiregulin expression was significantly higher in NSCLC patients that developed stable disease compared with those that developed disease progression following gefitinib or erlotinib treatment. CONCLUSIONS: Amphiregulin expression may help select EGFR wild-type patients who are likely to develop stable disease from EGFR-targeted therapies.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Genes erbB-1 , Glicoproteínas/biossíntese , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Neoplasias Pulmonares/tratamento farmacológico , Quinazolinas/uso terapêutico , Anfirregulina , Anticorpos Monoclonais Humanizados , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Cetuximab , Família de Proteínas EGF , Gefitinibe , Humanos , Neoplasias Pulmonares/genética , Mutação , Inibidores de Proteínas Quinases/farmacologia
11.
J Exp Med ; 215(8): 2115-2136, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-29997117

RESUMO

We have shown that antagomiR inhibition of miRNA miR-21 and miR-196b activity is sufficient to ablate MLL-AF9 leukemia stem cells (LSC) in vivo. Here, we used an shRNA screening approach to mimic miRNA activity on experimentally verified miR-196b targets to identify functionally important and therapeutically relevant pathways downstream of oncogenic miRNA in MLL-r AML. We found Cdkn1b (p27Kip1) is a direct miR-196b target whose repression enhanced an embryonic stem cell-like signature associated with decreased leukemia latency and increased numbers of leukemia stem cells in vivo. Conversely, elevation of p27Kip1 significantly reduced MLL-r leukemia self-renewal, promoted monocytic differentiation of leukemic blasts, and induced cell death. Antagonism of miR-196b activity or pharmacologic inhibition of the Cks1-Skp2-containing SCF E3-ubiquitin ligase complex increased p27Kip1 and inhibited human AML growth. This work illustrates that understanding oncogenic miRNA target pathways can identify actionable targets in leukemia.


Assuntos
Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , MicroRNAs/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Animais , Carcinogênese/genética , Carcinogênese/patologia , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular/genética , Cromossomos Humanos Par 11/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Células-Tronco Embrionárias/metabolismo , Regulação Leucêmica da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/genética , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Oncogenes , RNA Interferente Pequeno/metabolismo
12.
Clin Cancer Res ; 12(3 Pt 1): 751-8, 2006 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-16467085

RESUMO

PURPOSE: Mutations in the epidermal growth factor receptor (EGFR) are associated with clinical and radiographic responses to EGFR tyrosine kinase inhibitors gefitinib and erlotinib. Currently available methods of EGFR mutation detection rely on direct DNA sequencing, which requires isolation of DNA from a relatively pure population of tumor cells, cannot be done on small diagnostic specimens, and lack sensitivity. Here we describe the use of a sensitive screening method that overcomes many of these limitations. EXPERIMENTAL DESIGN: We screened 178 non-small cell lung cancer specimens for mutations in exons 18 to 21 of EGFR using a DNA endonuclease, SURVEYOR, which cleaves mismatched heteroduplexed DNA. Samples were analyzed by high-performance liquid chromatography on the Transgenomic WAVE HS system. Selected specimens that produced digestion products using SURVEYOR were subsequently reanalyzed by size separation or under partially denaturing conditions, followed by fractionation and sequencing. The specimens included DNA isolated from frozen tumor specimens, dissected formalin-fixed, paraffin-embedded tumor specimens undergoing clinical sequencing, and undissected formalin-fixed, paraffin-embedded specimens. One hundred sixty specimens were independently analyzed using direct DNA sequencing in a blinded fashion. RESULTS: EGFR mutations were detected in 16 of 61 fresh frozen tumor specimens, 24 of 91 dissected formalin-fixed, paraffin-embedded tumor specimens, and 11 of 26 undissected formalin-fixed, paraffin-embedded tumor specimens. Compared with sequencing, the sensitivity and specificity of the present method were 100% and 87%. The positive and negative predictive values were 74% and 100%, respectively. SURVEYOR analysis detected 7 (4%) mutations that were not previously detected by direct sequencing. CONCLUSIONS: SURVEYOR analysis provides a rapid method for EGFR mutation screening with 100% sensitivity and negative predictive value. This unbiased scanning technique is superior to direct sequencing when used with undissected formalin-fixed, paraffin-embedded specimens.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Desoxirribonuclease I , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Análise Mutacional de DNA/métodos , DNA de Neoplasias/química , DNA de Neoplasias/isolamento & purificação , Éxons , Feminino , Formaldeído/química , Gefitinibe , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Mutação , Inclusão em Parafina , Valor Preditivo dos Testes , Quinazolinas/uso terapêutico , Sensibilidade e Especificidade
13.
Melanoma Res ; 22(2): 123-32, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22343486

RESUMO

Uveal melanoma (UM) has a high propensity to develop hepatic metastases. We sought to define the mechanisms required for preferential liver homing and to understand further the biologic behavior of this disease. The Met tyrosine kinase receptor and its ligand hepatocyte growth factor are expressed in hepatocytes. We therefore considered Met/hepatocyte growth factor signaling as a candidate migration/growth factor for UM cells. We further explored the relationship between c-Met and other growth factor receptors prevalent in the liver and their roles in UM metastatic potential. UM cell lines were evaluated for c-Met, epidermal growth factor receptor (EGFR), and insulin-like growth factor-1R (IGF-1R) expression by immunoblotting, and gene amplification by comparative genomic hybridization and fluorescence in-situ hybridization. High c-Met, phosphorylated c-Met, and EGFR expression were noted in two of nine cell lines, independent of IGF-1R levels. Knockdown of c-Met decreased proliferation of high c-Met-expressing UM cells but did not induce apoptosis. Selective inhibitors of EGFR and IGF-1R decreased proliferation and induced apoptosis in UM cells regardless of the expression levels of c-Met, EGFR, and IGF-1R. Although c-Met, EGFR, and IGF-1R play proliferative roles, EGFR and IGF-1R are also critical for UM cell survival. High c-Met/EGFR-expressing cell lines possessed the greatest migration potential. c-Met knockdown and selective inhibitors of c-Met, EGFR, and IGF-1R revealed independent contribution of these receptors to migration. UM can be categorized by levels of c-Met and EGFR expression which are associated with migratory/invasiveness responses to soluble factors present at high levels in the liver. This provides biologic relevance for UM clinical behavior with potential therapeutic implications.


Assuntos
Receptores ErbB/metabolismo , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento Insulin-Like I/metabolismo , Melanoma/metabolismo , Melanoma/patologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Neoplasias Uveais/metabolismo , Neoplasias Uveais/patologia , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Hibridização Genômica Comparativa , Hepatócitos/citologia , Humanos , Hibridização in Situ Fluorescente , Neoplasias Hepáticas/patologia , Modelos Biológicos , Invasividade Neoplásica , Metástase Neoplásica
14.
Science ; 316(5827): 1039-43, 2007 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-17463250

RESUMO

The epidermal growth factor receptor (EGFR) kinase inhibitors gefitinib and erlotinib are effective treatments for lung cancers with EGFR activating mutations, but these tumors invariably develop drug resistance. Here, we describe a gefitinib-sensitive lung cancer cell line that developed resistance to gefitinib as a result of focal amplification of the MET proto-oncogene. inhibition of MET signaling in these cells restored their sensitivity to gefitinib. MET amplification was detected in 4 of 18 (22%) lung cancer specimens that had developed resistance to gefitinib or erlotinib. We find that amplification of MET causes gefitinib resistance by driving ERBB3 (HER3)-dependent activation of PI3K, a pathway thought to be specific to EGFR/ERBB family receptors. Thus, we propose that MET amplification may promote drug resistance in other ERBB-driven cancers as well.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Amplificação de Genes , Proteínas Proto-Oncogênicas/genética , Quinazolinas/farmacologia , Receptor ErbB-3/metabolismo , Receptores de Fatores de Crescimento/genética , Transdução de Sinais , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Células CHO , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cricetinae , Cricetulus , Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos , Gefitinibe , Humanos , Indóis/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-met , Quinazolinas/uso terapêutico , Receptores de Fatores de Crescimento/metabolismo , Sulfonas/farmacologia
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