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1.
Proc Natl Acad Sci U S A ; 117(33): 20139-20148, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32727899

RESUMO

Lung cancer causes more deaths annually than any other malignancy. A subset of non-small cell lung cancer (NSCLC) is driven by amplification and overexpression or activating mutation of the receptor tyrosine kinase (RTK) ERBB2 In some contexts, notably breast cancer, alternative splicing of ERBB2 causes skipping of exon 16, leading to the expression of an oncogenic ERBB2 isoform (ERBB2ΔEx16) that forms constitutively active homodimers. However, the broader implications of ERBB2 alternative splicing in human cancers have not been explored. Here, we have used genomic and transcriptomic analysis to identify elevated ERBB2ΔEx16 expression in a subset of NSCLC cases, as well as splicing site mutations facilitating exon 16 skipping and deletions of exon 16 in a subset of these lung tumors and in a number of other carcinomas. Supporting the potential of ERBB2ΔEx16 as a lung cancer driver, its expression transformed immortalized lung epithelial cells while a transgenic model featuring inducible ERBB2ΔEx16 specifically in the lung epithelium rapidly developed lung adenocarcinomas following transgene induction. Collectively, these observations indicate that ERBB2ΔEx16 is a lung cancer oncogene with potential clinical importance for a proportion of patients.


Assuntos
Carcinoma/genética , Predisposição Genética para Doença , Neoplasias Pulmonares/genética , Isoformas de Proteínas/genética , Receptor ErbB-2/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Camundongos , Ratos , Receptor ErbB-2/genética , Microambiente Tumoral
2.
J Immunol ; 204(9): 2392-2400, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32213561

RESUMO

Deregulation of mRNA translation engenders many human disorders, including obesity, neurodegenerative diseases, and cancer, and is associated with pathogen infections. The role of eIF4E-dependent translational control in macrophage inflammatory responses in vivo is largely unexplored. In this study, we investigated the involvement of the translation inhibitors eIF4E-binding proteins (4E-BPs) in the regulation of macrophage inflammatory responses in vitro and in vivo. We show that the lack of 4E-BPs exacerbates inflammatory polarization of bone marrow-derived macrophages and that 4E-BP-null adipose tissue macrophages display enhanced inflammatory gene expression following exposure to a high-fat diet (HFD). The exaggerated inflammatory response in HFD-fed 4E-BP-null mice coincides with significantly higher weight gain, higher Irf8 mRNA translation, and increased expression of IRF8 in adipose tissue compared with wild-type mice. Thus, 4E-BP-dependent translational control limits, in part, the proinflammatory response during HFD. These data underscore the activity of the 4E-BP-IRF8 axis as a paramount regulatory mechanism of proinflammatory responses in adipose tissue macrophages.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Tecido Adiposo/metabolismo , Inflamação/genética , Fatores Reguladores de Interferon/genética , Macrófagos/metabolismo , Biossíntese de Proteínas/genética , Animais , Medula Óssea/metabolismo , Dieta Hiperlipídica/métodos , Fator de Iniciação 4E em Eucariotos/genética , Expressão Gênica/genética , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
3.
N C Med J ; 80(1): 19-26, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30622199

RESUMO

BACKGROUND In response to the National Lung Screening Trial, numerous professional organizations published guidelines recommending annual lung cancer screening with low-dose computed tomography (LDCT) for high-risk patients. Prior studies found that physician attitudes and knowledge about lung cancer screening directly impacts the number of screening exams ordered.METHODS In 2015, we surveyed 34 pulmonologists and 186 primary care providers (PCPs) to evaluate opinions and practices of lung cancer screening in a large academic medical center. We compared PCP and pulmonologist responses using t-tests and χ2 tests.RESULTS The overall survey response rate was 40% (39% for PCPs and 50% for pulmonologists). Pulmonologists were more likely than PCPs to report lung cancer screening as beneficial for patients (88.2% versus 37.7%, P < .0001) and as being cost-effective (47.1% versus 14.3%, P = .02). More pulmonologists (76%) reported ordering a LDCT for screening in the past 12 months compared to PCPs (41%, P = .012). Pulmonologists and PCPs reported similar barriers to referring patients for lung cancer screening, including patient costs (82.4% versus 77.8%), potential for emotional harm (58.8% versus 58.3%), high false positive rate (47.1% versus 69.4%), and likelihood for medical complications (47.1% versus 59.7%).LIMITATIONS Our results are generalizable to academic medical centers and responses may be susceptible to recall bias, non-response bias, and social desirability bias.CONCLUSION We found significant differences in opinions and practices between PCPs and pulmonologists regarding lung cancer screening referrals and perceived benefits. As lung cancer screening continues to emerge in clinical practice, it is important to understand these differences across provider specialty to ensure screening is implemented and offered to patients appropriately.


Assuntos
Atitude do Pessoal de Saúde , Detecção Precoce de Câncer/psicologia , Detecção Precoce de Câncer/estatística & dados numéricos , Neoplasias Pulmonares/prevenção & controle , Médicos de Atenção Primária/psicologia , Padrões de Prática Médica/estatística & dados numéricos , Pneumologistas/psicologia , Centros Médicos Acadêmicos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Médicos de Atenção Primária/estatística & dados numéricos , Pneumologistas/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Tomografia Computadorizada por Raios X , Estados Unidos
4.
Mol Biol Evol ; 35(10): 2401-2413, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29955862

RESUMO

Managing the emergence and spread of crop pests and pathogens is essential for global food security. Understanding how organisms have adapted to their native climate is key to predicting the impact of climate change. The potato cyst nematodes Globodera pallida and G. rostochiensis are economically important plant pathogens that cause yield losses of up to 50% in potato. The two species have different thermal optima that may relate to differences in the altitude of their regions of origin in the Andes. Here, we demonstrate that juveniles of G. pallida are less able to recover from heat stress than those of G. rostochiensis. Genome-wide analysis revealed that while both Globodera species respond to heat stress by induction of various protective heat-inducible genes, G. pallida experiences heat stress at lower temperatures. We use C. elegans as a model to demonstrate the dependence of the heat stress response on expression of Heat Shock Factor-1 (HSF-1). Moreover, we show that hsp-110 is induced by heat stress in G. rostochiensis, but not in the less thermotolerant G. pallida. Sequence analysis revealed that this gene and its promoter was duplicated in G. rostochiensis and acquired thermoregulatory properties. We show that hsp-110 is required for recovery from acute thermal stress in both C. elegans and in G. rostochiensis. Our findings point towards an underlying molecular mechanism that allows the differential expansion of one species relative to another closely related species under current climate change scenarios. Similar mechanisms may be true of other invertebrate species with pest status.


Assuntos
Mudança Climática , Duplicação Gênica , Proteínas de Choque Térmico HSP110/genética , Resposta ao Choque Térmico , Rabditídios/genética , Animais , Feminino , Proteínas de Choque Térmico HSP110/metabolismo , Temperatura Alta , Rabditídios/metabolismo , Especificidade da Espécie
5.
Glob Chang Biol ; 23(11): 4497-4507, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28261933

RESUMO

The potato cyst nematodes Globodera pallida and G. rostochiensis are economically important plant pathogens causing losses to UK potato harvests estimated at £50 m/ year. Implications of climate change on their future pest status have not been fully considered. Here, we report growth of female G. pallida and G. rostochiensis over the range 15 to 25°C. Females per plant and their fecundity declined progressively with temperatures above 17.5°C for G. pallida, whilst females per plant were optimal between 17.5 and 22.5°C for G. rostochiensis. Relative reproductive success with temperature was confirmed on two potato cultivars infected with either species at 15, 22.5 and 25°C. The reduced reproductive success of G. pallida at 22.5°C relative to 15°C was also recorded for a further seven host cultivars studied. The differences in optimal temperatures for reproductive success may relate to known differences in the altitude of their regions of origin in the Andes. Exposure of G. pallida to a diurnal temperature stress for one week during female growth significantly suppressed subsequent growth for one week at 17.5°C but had no effect on G. rostochiensis. However, after two weeks of recovery, female size was not significantly different from that for the control treatment. Future soil temperatures were simulated for medium- and high-emission scenarios and combined with nematode growth data to project future implications of climate change for the two species. Increased soil temperatures associated with climate change may reduce the pest status of G. pallida but benefit G. rostochiensis especially in the southern United Kingdom. We conclude that plant breeders may be able to exploit the thermal limits of G. pallida by developing potato cultivars able to grow under future warm summer conditions. Existing widely deployed resistance to G. rostochiensis is an important characteristic to retain for new potato cultivars.


Assuntos
Mudança Climática , Solanum tuberosum/parasitologia , Tylenchoidea/fisiologia , Animais , Feminino , Solo , Reino Unido
6.
J Am Coll Radiol ; 14(2): 166-170, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28341213

RESUMO

BACKGROUND: The burden of lung cancer in the United States is staggering, with more Americans dying from lung cancer than the next four most common cancers combined. With endorsement of lung cancer screening by the United States Preventive Services Task Force and reimbursement by CMS, the number screened for lung cancer with low-dose CT (LDCT) is anticipated to rise in the near future. METHODS: In 2015, we conducted a cross-sectional study of mailed surveys to 112 ACR CT facilities across North Carolina to examine recommended guidelines for lung cancer screening, referral patterns, and patient tracking methods. We describe the survey results and compare findings with surveys of academic medical centers. RESULTS: Among 48 respondents (response rate = 42.9%), 54.2% offer lung cancer screening with LDCT (93.1% community and 6.9% academic settings); of these, 70.8% use ACR/CMS guidelines. In lung cancer screening facilities, reported patient volumes are low (average eight patients screened per month, range: 0-30) and patient tracking occurs in 72% of facilities. CONCLUSIONS: Among our predominately community-based sample of facilities, we found variation in lung cancer screening guideline usage, number of patients screened, and tracking methods.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Programas de Rastreamento , Guias de Prática Clínica como Assunto , Tomografia Computadorizada por Raios X , Estudos Transversais , Detecção Precoce de Câncer , Feminino , Humanos , Neoplasias Pulmonares/epidemiologia , Masculino , North Carolina/epidemiologia , Inquéritos e Questionários
7.
Risk Manag Healthc Policy ; 10: 189-195, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29403320

RESUMO

INTRODUCTION: The US Preventive Services Task Force recommended annual lung cancer screening with low-dose computed tomography (LDCT) for high-risk patients in December 2013. We compared lung cancer screening-related opinions and practices among attending and resident primary care physicians (PCPs). METHODS: In 2015, we conducted a 23-item survey among physicians at a large academic medical center. We surveyed 100 resident PCPs (30% response rate) and 86 attending PCPs (49% response rate) in Family Medicine and Internal Medicine. The questions focused on physicians' opinions, knowledge of recommendations, self-reported practice patterns, and barriers to lung cancer screening. In 2015 and 2016, we compared responses among attending versus resident PCPs using chi-square/Fisher's exact tests and 2-samples t-tests. RESULTS: Compared with resident PCPs, attending PCPs were older (mean age =47 vs 30 years) and more likely to be male (54% vs 37%). Over half of both groups concurred that inconsistent recommendations make deciding whether or not to screen difficult. A substantial proportion in both groups indicated that they were undecided about the benefit of lung cancer screening for patients (43% attending PCPs and 55% resident PCPs). The majority of attending and resident PCPs agreed that barriers to screening included limited time during patient visits (62% and 78%, respectively), cost to patients (74% and 83%, respectively), potential for complications (53% and 70%, respectively), and a high false-positive rate (67% and 73%, respectively). CONCLUSION: There was no evidence to suggest that attending and resident PCPs had differing opinions about lung cancer screening. For population-based implementation of lung cancer screening, physicians and trainees will need resources and time to address the benefits and harms with their patients.

8.
Genome Biol ; 17(1): 124, 2016 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-27286965

RESUMO

BACKGROUND: The yellow potato cyst nematode, Globodera rostochiensis, is a devastating plant pathogen of global economic importance. This biotrophic parasite secretes effectors from pharyngeal glands, some of which were acquired by horizontal gene transfer, to manipulate host processes and promote parasitism. G. rostochiensis is classified into pathotypes with different plant resistance-breaking phenotypes. RESULTS: We generate a high quality genome assembly for G. rostochiensis pathotype Ro1, identify putative effectors and horizontal gene transfer events, map gene expression through the life cycle focusing on key parasitic transitions and sequence the genomes of eight populations including four additional pathotypes to identify variation. Horizontal gene transfer contributes 3.5 % of the predicted genes, of which approximately 8.5 % are deployed as effectors. Over one-third of all effector genes are clustered in 21 putative 'effector islands' in the genome. We identify a dorsal gland promoter element motif (termed DOG Box) present upstream in representatives from 26 out of 28 dorsal gland effector families, and predict a putative effector superset associated with this motif. We validate gland cell expression in two novel genes by in situ hybridisation and catalogue dorsal gland promoter element-containing effectors from available cyst nematode genomes. Comparison of effector diversity between pathotypes highlights correlation with plant resistance-breaking. CONCLUSIONS: These G. rostochiensis genome resources will facilitate major advances in understanding nematode plant-parasitism. Dorsal gland promoter element-containing effectors are at the front line of the evolutionary arms race between plant and parasite and the ability to predict gland cell expression a priori promises rapid advances in understanding their roles and mechanisms of action.


Assuntos
Genoma de Protozoário , Doenças das Plantas/parasitologia , Solanum tuberosum/parasitologia , Tylenchoidea/genética , Tylenchoidea/patogenicidade , Animais , Elementos Facilitadores Genéticos , Perfilação da Expressão Gênica , Transferência Genética Horizontal , Ilhas Genômicas , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Estágios do Ciclo de Vida , Motivos de Nucleotídeos , Matrizes de Pontuação de Posição Específica , Sítios de Splice de RNA , Splicing de RNA , Transcriptoma , Tylenchoidea/crescimento & desenvolvimento , Virulência/genética
9.
Cancer Res ; 76(6): 1416-28, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26719528

RESUMO

Immunosurveillance constitutes the first step of cancer immunoediting in which developing malignant lesions are eliminated by antitumorigenic immune cells. However, the mechanisms by which neoplastic cells induce an immunosuppressive state to evade the immune response are still unclear. The transcription factor STAT3 has been implicated in breast carcinogenesis and tumor immunosuppression in advanced disease, but its involvement in early disease development has not been established. Here, we genetically ablated Stat3 in the tumor epithelia of the inducible PyVmT mammary tumor model and found that Stat3-deficient mice recapitulated the three phases of immunoediting: elimination, equilibrium, and escape. Pathologic analyses revealed that Stat3-deficient mice initially formed hyperplastic and early adenoma-like lesions that later completely regressed, thereby preventing the emergence of mammary tumors in the majority of animals. Furthermore, tumor regression was correlated with massive immune infiltration into the Stat3-deficient lesions, leading to their elimination. In a minority of animals, focal, nonmetastatic Stat3-deficient mammary tumors escaped immune surveillance after a long latency or equilibrium period. Taken together, our findings suggest that tumor epithelial expression of Stat3 plays a critical role in promoting an immunosuppressive tumor microenvironment during breast tumor initiation and progression, and prompt further investigation of Stat3-inhibitory strategies that may reactivate the immunosurveillance program.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Tolerância Imunológica/fisiologia , Vigilância Imunológica/fisiologia , Metástase Neoplásica/patologia , Fator de Transcrição STAT3/metabolismo , Microambiente Tumoral/fisiologia , Animais , Carcinogênese/metabolismo , Carcinogênese/patologia , Feminino , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Camundongos
10.
Genome Biol ; 15(3): R43, 2014 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-24580726

RESUMO

BACKGROUND: Globodera pallida is a devastating pathogen of potato crops, making it one of the most economically important plant parasitic nematodes. It is also an important model for the biology of cyst nematodes. Cyst nematodes and root-knot nematodes are the two most important plant parasitic nematode groups and together represent a global threat to food security. RESULTS: We present the complete genome sequence of G. pallida, together with transcriptomic data from most of the nematode life cycle, particularly focusing on the life cycle stages involved in root invasion and establishment of the biotrophic feeding site. Despite the relatively close phylogenetic relationship with root-knot nematodes, we describe a very different gene family content between the two groups and in particular extensive differences in the repertoire of effectors, including an enormous expansion of the SPRY domain protein family in G. pallida, which includes the SPRYSEC family of effectors. This highlights the distinct biology of cyst nematodes compared to the root-knot nematodes that were, until now, the only sedentary plant parasitic nematodes for which genome information was available. We also present in-depth descriptions of the repertoires of other genes likely to be important in understanding the unique biology of cyst nematodes and of potential drug targets and other targets for their control. CONCLUSIONS: The data and analyses we present will be central in exploiting post-genomic approaches in the development of much-needed novel strategies for the control of G. pallida and related pathogens.


Assuntos
Genoma Helmíntico , Estágios do Ciclo de Vida/genética , Transcriptoma , Tylenchoidea/genética , Animais , Sequência de Bases , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Filogenia , Tylenchoidea/crescimento & desenvolvimento , Tylenchoidea/parasitologia , Virulência/genética
11.
Mol Oncol ; 5(6): 517-26, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22075057

RESUMO

Focal adhesion kinase (FAK), a cytoplasmic tyrosine kinase and scaffold protein localized to focal adhesions, is uniquely positioned at the convergence point of integrin and receptor tyrosine kinase signal transduction pathways. FAK is overexpressed in many tumor cells, hence various inhibitors targeting its activity have been tested for anti-tumor activity. However, the direct effects of these pharmacologic agents on the endothelial cells of the vasculature have not been examined. Using primary human umbilical vein endothelial cells (HUVEC), we characterized the effects of two FAK inhibitors, PF-573,228 and FAK Inhibitor 14 on essential processes for angiogenesis, such as migration, proliferation, viability and endothelial cell tube formation. We observed that treatment with either FAK Inhibitor 14 or PF-573,228 resulted in reduced HUVEC viability, migration and tube formation in response to vascular endothelial growth factor (VEGF). Furthermore, we found that PF-573,228 had the added ability to induce apoptosis of endothelial cells within 36 h post-drug administration even in the continued presence of VEGF stimulation. FAK inhibitors also resulted in modification of the actin cytoskeleton within HUVEC, with observed increased stress fiber formation in the presence of drug. Given that endothelial cells were sensitive to FAK inhibitors at concentrations well below those reported to inhibit tumor cell migration, we confirmed their ability to inhibit endothelial-derived FAK autophosphorylation and FAK-mediated phosphorylation of recombinant paxillin at these doses. Taken together, our data indicate that small molecule inhibitors of FAK are potent anti-angiogenic agents and suggest their utility in combinatorial therapeutic approaches targeting tumor angiogenesis.


Assuntos
Inibidores da Angiogênese/farmacologia , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Quinolonas/farmacologia , Sulfonas/farmacologia , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Fosforilação/efeitos dos fármacos
12.
PLoS One ; 6(3): e17475, 2011 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-21408216

RESUMO

Cyst nematodes are a group of plant pathogens each with a defined host range that cause major losses to crops including potato, soybean and sugar beet. The infective mobile stage hatches from dormant eggs and moves a short distance through the soil to plant roots, which it then invades. A novel strategy for control has recently been proposed in which the plant is able to secrete a peptide which disorientates the infective stage and prevents invasion of the pathogen. This study provides indirect evidence to support the mechanism by which one such peptide disrupts chemosensory function in nematodes. The peptide is a disulphide-constrained 7-mer with the amino acid sequence CTTMHPRLC that binds to nicotinic acetylcholine receptors. A fluorescently tagged version of this peptide with both epifluorescent and confocal microscopy was used to demonstrate that retrograde transport occurs from an aqueous environment along bare-ending primary cilia of chemoreceptive sensilla. The peptide is transported to the cell bodies of these neurons and on to a limited number of other neurons to which they connect. It appears to be localised in both neuronal processes and organelles adjacent to nuclei of some neurons suggesting it could be transported through the Golgi apparatus. The peptide takes 2.5 h to reach the neuronal cell bodies. Comparative studies established that similar but less abundant uptake occurs for Caenorhabditis elegans along its well studied dye-filling chemoreceptive neurons. Incubation in peptide solution or root-exudate from transgenic plants that secrete the peptide disrupted normal orientation of infective cyst nematodes to host root diffusate. The peptide probably undergoes transport along the dye-filling non-cholinergic chemoreceptive neurons to their synapses where it is taken up by the interneurons to which they connect. Coordinated responses to chemoreception are disrupted when the sub-set of cholinergic interneurons secrete the peptide at synapses that have post-synaptic nicotinic acetylcholine receptors.


Assuntos
Células Quimiorreceptoras/metabolismo , Nematoides/metabolismo , Peptídeos/metabolismo , Plantas/parasitologia , Sequência de Aminoácidos , Animais , Comportamento Animal/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Células Quimiorreceptoras/efeitos dos fármacos , Quimiotaxia/efeitos dos fármacos , Corantes Fluorescentes/metabolismo , Dados de Sequência Molecular , Nematoides/citologia , Nematoides/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacologia , Raízes de Plantas/efeitos dos fármacos , Plantas/efeitos dos fármacos
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