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Body mass results from a complex interplay between genetics and environment. Previous studies of the genetic contribution to body mass have excluded repetitive regions due to the technical limitations of platforms used for population scale studies. Here we apply genome-wide approaches, identifying an association between adult body mass and the copy number (CN) of 47S-ribosomal DNA (rDNA). rDNA codes for the 18 S, 5.8 S and 28 S ribosomal RNA (rRNA) components of the ribosome. In mammals, there are hundreds of copies of these genes. Inter-individual variation in the rDNA CN has not previously been associated with a mammalian phenotype. Here, we show that rDNA CN variation associates with post-pubertal growth rate in rats and body mass index in adult humans. rDNA CN is not associated with rRNA transcription rates in adult tissues, suggesting the mechanistic link occurs earlier in development. This aligns with the observation that the association emerges by early adulthood.
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Índice de Massa Corporal , Variações do Número de Cópias de DNA , DNA Ribossômico , Animais , Humanos , DNA Ribossômico/genética , Masculino , Ratos , Feminino , Adulto , Mamíferos/genética , RNA Ribossômico/genética , RNA Ribossômico/metabolismoRESUMO
The evolution of primary melanoma to lymph node and distant metastasis is incompletely understood. We examined the genomic diversity in melanoma progression in matched primary melanomas and lymph node and distant metastases from 17 patients. FISH analysis revealed cancer cell fractions with monotonic copy number alterations, including PHIP gain and PTEN loss, in the metastatic cascade. By contrast, the cancer cell fraction with copy number alterations for BPTF and MITF was reduced in lymph node metastases but increased in distant metastases. Separately, the cancer cell fraction with NCOA3 copy number alteration was comparable between primary tumors and lymph node metastases yet increased in distant metastases. These results suggest enrichment of the phosphoinositide 3-kinase and MITF pathways in the transition through the metastatic cascade. By contrast, next-generation sequencing analysis did not identify a consistent pattern of changes in variant allele frequency while revealing several intriguing findings, including decreased variant allele frequency in distant metastases and distinct drivers in lymph node versus distant metastases. These results provide evidence that distant melanoma metastasis does not always emanate from lymph node metastasis. These results enhance our understanding of clonal patterns of melanoma metastasis, with possible implications for targeted therapy and metastasis competency.
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OBJECTIVES: We hypothesized that the immunosuppressive effects associated with antibiotics, sedatives, and catecholamines amplify sepsis-associated immune suppression through mitochondrial dysfunction, and there is a cumulative effect when used in combination. We thus sought to determine the impact of the exemplar drugs ciprofloxacin, propofol, and norepinephrine, used alone and in combination, at clinically relevant concentrations, on the ex vivo functionality of peripheral blood mononuclear cells (PBMCs) drawn from healthy, infected, and septic individuals. DESIGN: In vitro/ex vivo investigation. SETTING: University laboratory. SUBJECTS: Healthy volunteers, infected (nonseptic) patients in the emergency department, and septic ICU patients. INTERVENTIONS: PBMCs were isolated from these subjects and treated with ciprofloxacin (100 µg/mL), propofol (50 µg/mL), norepinephrine (10 µg/mL), or all three drugs combined, with and without lipopolysaccharide (100 ng/mL) for 6 or 24 hours. Comparison was made between study groups and against untreated cells. Measurements were made of cell viability, cytokine production, phagocytosis, human leukocyte antigen-DR (HLA-DR) status, mitochondrial membrane potential, mitochondrial reactive oxygen species production, and oxygen consumption. Gene expression in immune and metabolic pathways was investigated in PBMCs sampled from healthy volunteers coincubated with septic serum. MEASUREMENTS AND RESULTS: Coincubation with each of the drugs reduced cytokine production and phagocytosis in PBMCs isolated from septic patients, and healthy volunteers coincubated with septic serum. No effect was seen on HLA-DR surface expression. No cumulative effects were seen with the drug combination. Sepsis-induced changes in gene expression and mitochondrial functionality were not further affected by addition of any of the drugs. CONCLUSION: Drugs commonly used in critical care lead to significant immune dysfunction ex vivo and enhance sepsis-associated immunosuppression. Further studies are required to identify underlying mechanisms and potential impact on patient outcomes.
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Propofol , Sepse , Humanos , Catecolaminas , Hipnóticos e Sedativos/farmacologia , Antibacterianos , Leucócitos Mononucleares , Norepinefrina , Terapia de Imunossupressão , Ciprofloxacina , Antígenos HLA-DR , CitocinasRESUMO
Importance: Refining eligibility guidelines may identify more appropriate patients to undergo useful medical procedures. Objective: To improve cost-effectiveness in selecting patients with melanoma for sentinel lymph node biopsy (SLNB). Design, Setting, and Participants: This hybrid prognostic study/decision analytical model was conducted among patients with melanoma who were eligible for SLNB at 2 melanoma centers from Australia and the US from 2000 to 2014. Participants consisted of 2 cohorts of patients with melanoma undergoing SLNB and a cohort of eligible patients without SLNB. Individualized probabilities of SLNB positivity generated by a patient-centered methodology (PCM) were compared with those generated by conventional multiple logistic regression analysis investigating 12 prognostic factors. Prognostic accuracy was assessed by the area under the receiver operating characteristic curve (AUROC) for each methodology and by matched-pair analyses. Interventions: Triaging appropriate patients to undergo SLNB. Main Outcomes and Measures: Total number of SLNBs performed (giving total cost) vs number of SLNB-positive outcomes (a measure of effectiveness) was evaluated. Improved cost-effectiveness through judicious patient selection was interpreted as increased numbers of SLNB-positive outcomes achieved, decreased numbers of SLNBs performed, or both outcomes simultaneously. Results: Among 7331 patients with melanoma, SLNB outcomes were assessed in 3640 Australian patients (2212 males [60.8%]; 2447 aged >50 years [67.2%]) and 1342 US patients (774 males [57.7%]; 885 aged >50 years [66.0%]); 2349 patients eligible for SLNB who did not undergo the procedure were included in the simulation. PCM-generated probabilities achieved an AUROC of 0.803 in predicting SLNB positivity in the Australian cohort and 0.826 in the US cohort, higher than corresponding AUROCs generated by conventional logistic regression analysis. In simulation, adopting many SLNB-positive probabilities as minimally acceptable patient-selection criteria resulted in fewer procedures performed or increased the expected numbers of positive SLNBs. A minimally acceptable PCM-generated probability of 8.7% elicited the same number of SLNBs as historically performed (3640 SLNBs), with 1066 positive SLNBs (29.3%), constituting an improvement of 287 additional positive SLNBs compared with 779 actual positive SLNBs (36.8% improvement). In contrast, adopting a 23.7% PCM-generated minimum cutoff probability resulted in performing 1825 SLNBs, or 1815 fewer SLNBs than the actual experience (49.9%). It resulted in the same expected number of positive results (779 SLNBs), for a 42.7% positivity rate. Conclusions and Relevance: This prognostic study/decision analytical model found that the PCM approach outperformed conventional multiple logistic regression analysis in predicting which patients would have positive results on SLNB. These findings suggest that systematically producing and exploiting more accurate SLNB-positivity probabilities could improve the selection of patients with melanoma for SLNB compared with using established guidelines, thus improving the cost-effectiveness of the selection process. Eligibility guidelines to undergo SLNB should include a context-tailored minimum cutoff probability.
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Melanoma , Neoplasias Cutâneas , Masculino , Humanos , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Cutâneas/patologia , Austrália , Melanoma/patologia , PrognósticoRESUMO
Recent advancements in imaging technology have led to increasing interest in home monitoring of macular disease. The prevalence of macular disease is projected to rise considerably over time, leading to a significant burden on hospital services for age-related macular degeneration and diabetic macular edema. Home monitoring has the potential to augment conventional hospital assessment and so enable improved access to clinical care for low- and moderate-risk patients, while also allowing sensitive detection of early signs of disease that may require prompt intervention. Despite this, there are significant considerations before large-scale implementation could be possible. These are related to both the current availability of home monitoring technology and the logistical barriers to its widespread introduction. Access to home monitoring is also likely to be more challenging in lower-income communities and countries, with subsequent implications for health inequality that will need to be considered and addressed appropriately.
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Purpose: To assess the biomarker and functional role of the chromatin remodeling factor, bromodomain PHD finger transcription factor (BPTF), in breast cancer progression. Methods: BPTF copy number was assessed using fluorescence in situ hybridization. BPTF expression was regulated in breast cancer cells by shRNA/siRNA-mediated gene silencing and BPTF cDNA overexpression. The effects of regulating BPTF expression were examined on key oncogenic signaling pathways and on breast cancer cell proliferation, apoptosis, and cell cycle progression, as well as in xenograft models. The consequences of pharmacological bromodomain inhibition, alone or in combination with other targeted agents, on breast cancer progression were assessed in culture and in xenograft models. Results: BPTF copy number was gained in 34.1% and separately amplified in 8.2% of a breast cancer tissue cohort. Elevated BPTF copy number was significantly associated with increasing patient age and tumor grade and observed in both ER-positive and triple-negative breast cancer (TNBC) subtypes. BPTF copy number gain and amplification were also observed in The Cancer Genome Atlas (TCGA) breast cancer cohort. Stable shRNA-mediated silencing of BPTF significantly inhibited cell proliferation and induced apoptosis in TNBC and ER-positive human breast cancer cell lines. BPTF knockdown suppressed signaling through the phosphoinositide 3 kinase (PI3K) pathway, including reduced expression of phosphorylated AKT (Ser473), phosphorylated GSK-ß (Ser9), and CCND1. These findings were confirmed following transient BPTF knockdown by a distinct siRNA in TNBC and ER-positive breast cancer cells. Stable suppression of BPTF expression significantly inhibited the in vivo growth of TNBC cells. Conversely, BPTF cDNA overexpression in TNBC and ER-positive breast cancer cells enhanced breast cancer cell proliferation and reduced apoptosis. BPTF targeting with the bromodomain inhibitor bromosporine, alone or in combination with the PI3K pathway inhibitor gedatolisib, produced significant anti-tumor effects against TNBC cells in vitro and in vivo. Conclusion: These studies demonstrate BPTF activation in distinct breast cancer subtypes, identify pathways by which BPTF promotes breast cancer progression, and suggest BPTF as a rational target for breast cancer therapy.
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Therapy of BRAF-mutant melanoma with selective inhibitors of BRAF (BRAFi) and MEK (MEKi) represents a major clinical advance but acquired resistance to therapy has emerged as a key obstacle. To date, no clinical approaches successfully resensitize to BRAF/MEK inhibition. Here, we develop a therapeutic strategy for melanoma using bromosporine, a bromodomain inhibitor. Bromosporine (bromo) monotherapy produced significant anti-tumor effects against established melanoma cell lines and patient-derived xenografts (PDXs). Combinatorial therapy involving bromosporine and cobimetinib (bromo/cobi) showed synergistic anti-tumor effects in multiple BRAFi-resistant PDX models. The bromo/cobi combination was superior in vivo to standard BRAFi/MEKi therapy in the treatment-naive BRAF-mutant setting and to MEKi alone in the setting of immunotherapy-resistant NRAS- and NF1-mutant melanoma. RNA sequencing of xenografts treated with bromo/cobi revealed profound down-regulation of genes critical to cell division and mitotic progression. Bromo/cobi treatment resulted in marked DNA damage and cell-cycle arrest, resulting in induction of apoptosis. These studies introduce bromodomain inhibition, alone or combined with agents targeting the mitogen activated protein kinase pathway, as a rational therapeutic approach for melanoma refractory to standard targeted or immunotherapeutic approaches.
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Melanoma , Proteínas Proto-Oncogênicas B-raf , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno , Proteínas Nucleares , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/metabolismo , Fatores de TranscriçãoRESUMO
Melanoma occurs as a consequence of inherited susceptibility to the disease and exposure to UV radiation (UVR) and is characterized by uncontrolled cellular proliferation and a high mutational load. The precise mechanisms by which UVR contributes to the development of melanoma remain poorly understood. Here we show that activation of nuclear receptor coactivator 3 (NCOA3) promotes melanomagenesis through regulation of UVR sensitivity, cell-cycle progression, and circumvention of the DNA damage response (DDR). Downregulation of NCOA3 expression, either by genetic silencing or small-molecule inhibition, significantly suppressed melanoma proliferation in melanoma cell lines and patient-derived xenografts. NCOA3 silencing suppressed expression of xeroderma pigmentosum C and increased melanoma cell sensitivity to UVR. Suppression of NCOA3 expression led to activation of DDR effectors and reduced expression of cyclin B1, resulting in G2-M arrest and mitotic catastrophe. A SNP in NCOA3 (T960T) reduced NCOA3 protein expression and was associated with decreased melanoma risk, given a significantly lower prevalence in a familial melanoma cohort than in a control cohort without cancer. Overexpression of wild-type NCOA3 promoted melanocyte survival following UVR and was accompanied by increased levels of UVR-induced DNA damage, both of which were attenuated by overexpression of NCOA3 (T960T). These results describe NCOA3-regulated pathways by which melanoma can develop, with germline NCOA3 polymorphisms enabling enhanced melanocyte survival in the setting of UVR exposure, despite an increased mutational burden. They also identify NCOA3 as a novel therapeutic target for melanoma. SIGNIFICANCE: This study explores NCOA3 as a regulator of the DDR and a therapeutic target in melanoma, where activation of NCOA3 contributes to melanoma development following exposure to ultraviolet light.
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Biomarcadores Tumorais/metabolismo , Dano ao DNA , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Melanoma/patologia , Coativador 3 de Receptor Nuclear/metabolismo , Lesões por Radiação/patologia , Raios Ultravioleta/efeitos adversos , Animais , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Feminino , Humanos , Melanoma/etiologia , Melanoma/metabolismo , Camundongos , Camundongos Nus , Mutação , Coativador 3 de Receptor Nuclear/genética , Lesões por Radiação/etiologia , Lesões por Radiação/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Homologous recombination DNA damage repair (HR-DDR) deficient patients with various solid tumors have been treated with PARP inhibitors. However, the clinical characteristics of patients with melanoma who have HR-DDR gene mutations and the consequences of PARP inhibition are poorly understood. We compared the commercially available next-generation sequencing data from 84 patients with melanomas from our institution with a dataset of 1,986 patients as well as 1,088 patients profiled in cBioportal. In total, 21.4% of patients had ≥1 functional HR-DDR mutation, most commonly involving BRCA1, ARID1A, ATM, ATR, and FANCA. Concurrent NF1, BRAF, and NRAS mutations were found in 39%, 39%, and 22% of cases, respectively. HR-DDR gene mutation was associated with high tumor mutational burden and clinical response to checkpoint blockade. A higher prevalence of HR-DDR mutations was observed in the datasets from Foundation Medicine (Cambridge, CA) and those from the Cancer Genome Atlas. Treatment of HR-DDRâmutated patient-derived xenograft models of melanoma with PARP inhibitor produced significant antitumor activity in vivo and was associated with increased apoptotic activity. RNA sequencing analysis of PARP inhibitor-treated tumors indicated alterations in the pathways involving extracellular matrix remodeling, cell adhesion, and cell-cycle progression. Melanomas with HR-DDR mutations represent a unique subset, which is more likely to benefit from checkpoint blockade and may be targeted with PARP inhibitor.
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Biomarcadores Tumorais/genética , Melanoma/genética , Reparo de DNA por Recombinação/genética , Neoplasias Cutâneas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Dano ao DNA/efeitos dos fármacos , Análise Mutacional de DNA/estatística & dados numéricos , Feminino , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Masculino , Melanoma/tratamento farmacológico , Melanoma/epidemiologia , Camundongos , Pessoa de Meia-Idade , Epidemiologia Molecular , Mutação , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Prevalência , Intervalo Livre de Progressão , RNA-Seq , Reparo de DNA por Recombinação/efeitos dos fármacos , Estudos Retrospectivos , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/epidemiologia , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto JovemRESUMO
Lyme disease, the most prevalent vector-borne disease in North America, is increasing in incidence and geographic distribution as the tick vector, Ixodes scapularis, spreads to new regions. We re-construct the spatial-temporal invasion of the tick and human disease in the Midwestern US, a major focus of Lyme disease transmission, from 1967 to 2018, to analyse the influence of spatial factors on the geographic spread. A regression model indicates that three spatial factors-proximity to a previously invaded county, forest cover and adjacency to a river-collectively predict tick occurrence. Validation of the predictive capability of this model correctly predicts counties invaded or uninvaded with 90.6% and 98.5% accuracy, respectively. Reported incidence increases in counties after the first report of the tick; based on this modelled relationship, we identify 31 counties where we suspect I. scapularis already occurs yet remains undetected. Finally, we apply the model to forecast tick establishment by 2021 and predict 42 additional counties where I. scapularis will probably be detected based upon historical drivers of geographic spread. Our findings leverage resources dedicated to tick and human disease reporting and provide the opportunity to take proactive steps (e.g. educational efforts) to prevent and limit transmission in areas of future geographic spread.
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Ixodes , Doença de Lyme/epidemiologia , Animais , Florestas , Humanos , Incidência , América do Norte/epidemiologiaRESUMO
Estimates of absolute pest population density are critical to pest management programs but have been difficult to obtain from capture numbers in pheromone-baited monitoring traps. In this paper, we establish a novel predictive relationship for a probability (spTfer(r)) of catching a male located at a distance r from the trap with a plume reach D.
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Non-native grasses used as forage for domestic livestock can negatively impact ecosystem services provided by grasslands. In the U.S., most grazed grasslands are privately owned so the introduction and reduction of non-native grasses are both driven by landowner behavior. Yet, the social factors that shape non-native grass management are rarely explored. To address this knowledge gap, we evaluated how decisions to reduce these grasses through practices such as herbicide application, prescribed fire, and physical removal are influenced by attitudes, norms, and perceived ability. We administered a mixed mode (mailback and online) survey in 2017 to landowners in the eastern Great Plains of the U.S., in a region where cattle production remains the predominant land-use. Using structural equation modeling with parceling, we tested hypotheses related to management decisions derived from a model integrating two theories - the Theory of Planned Behavior and the Norm Activation Model. In this analysis, we identified perceived ability (i.e., access to time, skills, or other necessary resources) as a barrier to adoption for landowners who were already willing to manage non-native grasses. Positive attitudes toward management and increased social norm pressures were both associated with increased sentiments of moral responsibility to reduce non-native grasses. These personal norms, together with attitudes, positively influenced willingness to control non-native grasses. Further, we observed that social norms related to expectations of neighbors had more influence on personal norms than the social norms from natural resource agencies. The power of norms to explain individual management decisions suggests that landowners could be engaged in landscape-scale initiatives by leveraging moral responsibility and influential social groups.
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Ecossistema , Incêndios , Animais , Atitude , Bovinos , Conservação dos Recursos Naturais , PoaceaeRESUMO
During a trapping study interval, each target insect is either caught or not caught. Therefore, the current analysis treats trapping as a binomial process. Data from a binomial calculator, along with computer simulations of random walkers, documented that the inherent variance associated with estimates of absolute population density generated by a single catch number in a pheromone-baited monitoring trap becomes very high when catch probability averaged across the trap's sampling area falls below 0.02, as is the case for most insect trapping systems operating in the open field. The imprecision associated with interpretations of single catch numbers renders many current pest management decisions risky and unsatisfactory. Here we reinforce how single-trap, multiple-release experiments can and should be used to measure catch probability, plume reach, and trap sampling area. When catch probability lies in the danger zone below 0.02, steps are suggested for how multiple traps might be deployed to raise composite catch probability to a level where estimates of absolute pest density become reliable. Heat transfer is offered as an appropriate conceptual model for the mechanics of trapping. A call is made for a radical rethinking in the designs of insect monitoring traps in light of their significant current deficits highlighted by this study.
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Controle de Insetos , Feromônios , Animais , Insetos , Densidade DemográficaRESUMO
BACKGROUND: Mitotic rate is a strong, independent prognostic factor in patients with melanoma. However, incorporating it into the melanoma staging system has proved challenging. METHODS: The prognostic impact of mitotic rate was assessed in a melanoma cohort comprising 5050 patients from 2 geographically distinct populations. Computer-generated cut points for mitotic rate were constructed to determine its impact on melanoma-associated survival using Kaplan-Meier and multivariate regression analyses. The impact of mitotic rate also was assessed in randomly split training and validation sets. RESULTS: Mitotic rate had a nonlinear impact on survival, as evidenced by unequally spaced cut points. An index incorporating these cut points that was constructed from one population produced significantly more accurate predictions of survival in the other population than using the entire scale of mitotic rate. An index constructed from the combined cohort was found to be independently predictive of survival, with an impact comparable to that of ulceration. Optimal high-versus-low cut points for mitotic rate were generated separately for each T category (<2 mitoses/mm2 vs ≥2 mitoses/mm2 for T1 melanoma, <4 mitoses/mm2 vs ≥4 mitoses/mm2 for T2 melanoma, <6 mitoses/mm2 vs ≥6/mitoses/mm2 for T3 melanoma, and <7 mitoses/mm2 vs ≥7 mitoses/mm2 for T4 melanoma). Using Kaplan-Meier analysis, elevated mitotic rate was found to have an impact on survival comparable to that of ulceration within each T category. Application of the index for mitotic rate that was constructed from the training data set demonstrated an independent impact in the validation data set, with a significance similar to that of ulceration. CONCLUSIONS: The results of the current study demonstrated the comparable prognostic impact of mitotic rate and ulceration, providing support for its reincorporation into the T category.
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Melanoma/genética , Índice Mitótico/métodos , Feminino , Humanos , Masculino , Melanoma/mortalidade , Estadiamento de Neoplasias , PrognósticoRESUMO
The invasive behavior of glioblastoma is essential to its aggressive potential. Here, we show that pleckstrin homology domain interacting protein (PHIP), acting through effects on the force transduction layer of the focal adhesion complex, drives glioblastoma motility and invasion. Immunofluorescence analysis localized PHIP to the leading edge of glioblastoma cells, together with several focal adhesion proteins: vinculin (VCL), talin 1 (TLN1), integrin beta 1 (ITGB1), as well as phosphorylated forms of paxillin (pPXN) and focal adhesion kinase (pFAK). Confocal microscopy specifically localized PHIP to the force transduction layer, together with TLN1 and VCL. Immunoprecipitation revealed a physical interaction between PHIP and VCL. Targeted suppression of PHIP resulted in significant down-regulation of these focal adhesion proteins, along with zyxin (ZYX), and produced profoundly disorganized stress fibers. Live-cell imaging of glioblastoma cells overexpressing a ZYX-GFP construct demonstrated a role for PHIP in regulating focal adhesion dynamics. PHIP silencing significantly suppressed the migratory and invasive capacity of glioblastoma cells, partially restored following TLN1 or ZYX cDNA overexpression. PHIP knockdown produced substantial suppression of tumor growth upon intracranial implantation, as well as significantly reduced microvessel density and secreted VEGF levels. PHIP copy number was elevated in the classical glioblastoma subtype and correlated with elevated EGFR levels. These results demonstrate PHIP's role in regulating the actin cytoskeleton, focal adhesion dynamics, and tumor cell motility, and identify PHIP as a key driver of glioblastoma migration and invasion.
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Neoplasias Encefálicas/patologia , Adesões Focais/patologia , Glioblastoma/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neovascularização Patológica/patologia , Citoesqueleto de Actina/metabolismo , Animais , Encéfalo/patologia , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/genética , Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Estudos de Coortes , Progressão da Doença , Feminino , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glioblastoma/irrigação sanguínea , Glioblastoma/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Microscopia Intravital , Camundongos , Microscopia Confocal , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Neovascularização Patológica/genética , Imagem com Lapso de Tempo , Vinculina/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Animals are predicted to prefer high-quality over low-quality habitats, but adaptive habitat selection is less straightforward than often assumed. Preferences may improve only specific fitness metrics at particular spatial scales, with variation across time or between sexes. Preferences sometimes even reduce fitness. We investigated the context specificity of adaptive habitat selection, studying dickcissels (Spiza americana)-a polygynous songbird-as a model. From 2014 to 2015, we measured male and female habitat preferences at two scales (territories and landscape patches) on 21 grassland patches in Ringgold County, Iowa, USA. We tested whether preferences improved four fitness metrics-polygyny, avoidance of brood parasitism by brown-headed cowbirds (Molothrus ater), fledgling productivity, and offspring condition. Both sexes preferred territories where offspring attained superior condition and patches where parasitism was infrequent. Females preferred patches where nests produced more fledglings, and in 2014, males on preferred (i.e., early-established) territories attracted more mates and produced more fledglings. However, males on non-preferred (i.e., late-established) territories were more successful in 2015. This inconsistency may have arisen because females were abundant and nest-predation rates were low in May-June 2014, allowing early-settling males to produce many young. In 2015, however, females were more abundant and nests more successful later in the breeding season. Our results show that habitat preferences do not uniformly improve fitness, and some benefits differ between sexes. Moreover, preference-fitness relationships only manifest at specific scales, and annual variation in population and predation dynamics can limit consistency. Detecting adaptive habitat selection thus requires multi-year measurements and careful consideration of relevant scales.
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Passeriformes , Aves Canoras , Animais , Ecossistema , Feminino , Pradaria , Masculino , Comportamento de Nidação , Comportamento PredatórioRESUMO
Millions of farm ponds have been constructed in agricultural landscapes around the globe. These ponds are built to support a variety of functions, including erosion control, cattle grazing, and recreational fishing, but their role as breeding habitat for amphibians remains poorly understood. We addressed this knowledge gap by studying farm ponds in the eastern Great Plains of the United States, a pond-dense region dominated by agriculture. We used field surveys and occupancy modeling to identify the important biophysical components of amphibian habitat and to assess the species-specific effects of cattle and fish presence on breeding occupancy. We next used a chronosequence to determine whether pond renovation, which often occurs when ponds are about 40 yr old, threatens the development of amphibian habitat. Nine amphibian species bred in the farm ponds that we surveyed, and the relationship between breeding occupancy and habitat variables varied by species. We found that the pH conditions associated with amphibian breeding occupancy were significantly more likely to occur in older ponds (>50 yr old). Emergent vegetation cover was also associated with increased breeding probability and rarely reached high levels in newer ponds. Since the older ponds with suitable habitat are at an age where renovation is likely needed to restore their agricultural function, this habitat may be at risk. We suggest that conservation of amphibians in farm ponds in the United States will require adopting renovation and management practices that balance the multiple uses of these sites and maintain a mosaic of pond successional states.
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Anfíbios , Lagoas , Agricultura , Animais , Cruzamento , Bovinos , Ecossistema , FazendasRESUMO
The identification and targeting of key molecular drivers of melanoma and breast and lung cancer have substantially improved their therapy. However, subtypes of each of these three common, lethal solid tumors lack identified molecular drivers, and are thus not amenable to targeted therapies. Here we show that pleckstrin homology domain-interacting protein (PHIP) promotes the progression of these "driver-negative" tumors. Suppression of PHIP expression significantly inhibited both tumor cell proliferation and invasion, coordinately suppressing phosphorylated AKT, cyclin D1, and talin1 expression in all three tumor types. Furthermore, PHIP's targetable bromodomain is functional, as it specifically binds the histone modification H4K91ac. Analysis of TCGA profiling efforts revealed PHIP overexpression in triple-negative and basal-like breast cancer, as well as in the bronchioid subtype of nonsmall cell lung cancer. These results identify a role for PHIP in the progression of melanoma and breast and lung cancer subtypes lacking identified targeted therapies. The use of selective, anti-PHIP bromodomain inhibitors may thus yield a broad-based, molecularly targeted therapy against currently nontargetable tumors.
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Mama/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Melanoma/metabolismo , Domínios de Homologia à Plecstrina/fisiologia , Neoplasias de Mama Triplo Negativas/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Ciclina D1/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
Purpose: Previous studies have indicated an important role for pleckstrin homology domain-interacting protein (PHIP) as a marker and mediator of melanoma metastasis. Here we aimed to confirm the role of PHIP copy number in successive stages of melanoma progression.Experimental Design:PHIP copy number was examined using FISH in three independent cohorts by recording the percentage of cells harboring ≥3 copies of PHIP The impact of PHIP copy number on survival was assessed using Cox regression analysis. The enrichment of PHIP was assessed in various molecular melanoma subtypes. PHIP expression was analyzed in The Cancer Genome Atlas (TCGA) melanoma cohort.Results: Elevated PHIP copy number was significantly predictive of reduced distant metastasis-free survival (DMFS) and disease-specific survival (DSS), and increased prevalence of ulceration in primary melanoma (cohort No. 1). By multivariate analysis, PHIP FISH scores were independently predictive of DMFS and DSS. PHIP copy number was enriched in metastatic melanomas harboring mutant NRAS or expressing PTEN protein (cohort No. 2). PHIP copy number was significantly elevated in metastatic melanomas when compared with matched primary tumors from the same patient (cohort No. 3). Several of these associations were replicated using TCGA cohort analysis.Conclusions: These results underscore the important role of PHIP copy-number elevation in melanoma progression, and identify molecular subtypes of melanoma in which PHIP is enriched. Finally, as elevated PHIP copy number appears to be selected for during the progression of primary to metastatic melanoma, these results confirm PHIP as a promising therapeutic target for melanoma. Clin Cancer Res; 24(17); 4119-25. ©2018 AACR.