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1.
Cell ; 149(2): 307-21, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22500798

RESUMO

Kinase inhibitors have limited success in cancer treatment because tumors circumvent their action. Using a quantitative proteomics approach, we assessed kinome activity in response to MEK inhibition in triple-negative breast cancer (TNBC) cells and genetically engineered mice (GEMMs). MEK inhibition caused acute ERK activity loss, resulting in rapid c-Myc degradation that induced expression and activation of several receptor tyrosine kinases (RTKs). RNAi knockdown of ERK or c-Myc mimicked RTK induction by MEK inhibitors, and prevention of proteasomal c-Myc degradation blocked kinome reprogramming. MEK inhibitor-induced RTK stimulation overcame MEK2 inhibition, but not MEK1 inhibition, reactivating ERK and producing drug resistance. The C3Tag GEMM for TNBC similarly induced RTKs in response to MEK inhibition. The inhibitor-induced RTK profile suggested a kinase inhibitor combination therapy that produced GEMM tumor apoptosis and regression where single agents were ineffective. This approach defines mechanisms of drug resistance, allowing rational design of combination therapies for cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos , MAP Quinase Quinase 1/antagonistas & inibidores , Proteínas Quinases/genética , Proteoma/análise , Animais , Antineoplásicos/uso terapêutico , Benzenossulfonatos/uso terapêutico , Benzimidazóis/uso terapêutico , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Niacinamida/análogos & derivados , Compostos de Fenilureia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Piridinas/uso terapêutico , Receptores Proteína Tirosina Quinases/genética , Sorafenibe
2.
J Proteome Res ; 22(10): 3159-3177, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37634194

RESUMO

Host kinases play essential roles in the host cell cycle, innate immune signaling, the stress response to viral infection, and inflammation. Previous work has demonstrated that coronaviruses specifically target kinase cascades to subvert host cell responses to infection and rely upon host kinase activity to phosphorylate viral proteins to enhance replication. Given the number of kinase inhibitors that are already FDA approved to treat cancers, fibrosis, and other human disease, they represent an attractive class of compounds to repurpose for host-targeted therapies against emerging coronavirus infections. To further understand the host kinome response to betacoronavirus infection, we employed multiplex inhibitory bead mass spectrometry (MIB-MS) following MERS-CoV and SARS-CoV-2 infection of human lung epithelial cell lines. Our MIB-MS analyses revealed activation of mTOR and MAPK signaling following MERS-CoV and SARS-CoV-2 infection, respectively. SARS-CoV-2 host kinome responses were further characterized using paired phosphoproteomics, which identified activation of MAPK, PI3K, and mTOR signaling. Through chemogenomic screening, we found that clinically relevant PI3K/mTOR inhibitors were able to inhibit coronavirus replication at nanomolar concentrations similar to direct-acting antivirals. This study lays the groundwork for identifying broad-acting, host-targeted therapies to reduce betacoronavirus replication that can be rapidly repurposed during future outbreaks and epidemics. The proteomics, phosphoproteomics, and MIB-MS datasets generated in this study are available in the Proteomics Identification Database (PRIDE) repository under project identifiers PXD040897 and PXD040901.


Assuntos
COVID-19 , Hepatite C Crônica , Coronavírus da Síndrome Respiratória do Oriente Médio , Humanos , Antivirais/farmacologia , Inibidores de MTOR , Fosfatidilinositol 3-Quinases , SARS-CoV-2 , Replicação Viral , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Serina-Treonina Quinases TOR
3.
Br J Cancer ; 128(9): 1690-1700, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36841908

RESUMO

BACKGROUND: Overweight and obesity are common amongst women attending breast cancer Family History, Risk and Prevention Clinics (FHRPCs). Overweight increases risk of breast cancer (BC) and conditions including1 cardiovascular disease (CVD) and type-2 diabetes (T2D). Clinics provide written health behaviour advice with is likely to have minimal effects. We assessed efficacy of two remotely delivered weight loss programmes vs. written advice. METHOD: 210 women with overweight or obesity attending three UK FHRPCs were randomised to either a BC prevention programme (BCPP) framed to reduce risk of BC (n = 86), a multiple disease prevention programme (MDPP) framed to reduce risk of BC, CVD and T2D (n = 87), or written advice (n = 37). Change in weight and health behaviours were assessed at 12-months. RESULTS: Weight loss at 12 months was -6.3% (-8.2, -4.5) in BCPP, -6.0% (-7.9, -4.2) in MDPP and -3.3% (-6.2, -0.5) in the written group (p = 0.451 across groups). The percentage losing ≥10% weight in these groups were respectively 34%, 23% and 14% (p = 0.038 across groups). DISCUSSION: BCPP and MDPP programmes resulted in more women achieving ≥10% weight loss, but no evidence of additional benefits of MDPP. A multicentre RCT to test the BCPP across UK FHRPCs is warranted. Clinical Trial Registration ISRCTN16431108.


Assuntos
Neoplasias da Mama , Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Programas de Redução de Peso , Humanos , Feminino , Sobrepeso/terapia , Programas de Redução de Peso/métodos , Neoplasias da Mama/prevenção & controle , Obesidade/prevenção & controle , Redução de Peso
4.
Int J Behav Nutr Phys Act ; 20(1): 35, 2023 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-36964597

RESUMO

BACKGROUND: Over the last decade use of raw acceleration metrics to assess physical activity has increased. Metrics such as Euclidean Norm Minus One (ENMO), and Mean Amplitude Deviation (MAD) can be used to generate metrics which describe physical activity volume (average acceleration), intensity distribution (intensity gradient), and intensity of the most active periods (MX metrics) of the day. Presently, relatively little comparative data for these metrics exists in youth. To address this need, this study presents age- and sex-specific reference percentile values in England youth and compares physical activity volume and intensity profiles by age and sex. METHODS: Wrist-worn accelerometer data from 10 studies involving youth aged 5 to 15 y were pooled. Weekday and weekend waking hours were first calculated for youth in school Years (Y) 1&2, Y4&5, Y6&7, and Y8&9 to determine waking hours durations by age-groups and day types. A valid waking hours day was defined as accelerometer wear for ≥ 600 min·d-1 and participants with ≥ 3 valid weekdays and ≥ 1 valid weekend day were included. Mean ENMO- and MAD-generated average acceleration, intensity gradient, and MX metrics were calculated and summarised as weighted week averages. Sex-specific smoothed percentile curves were generated for each metric using Generalized Additive Models for Location Scale and Shape. Linear mixed models examined age and sex differences. RESULTS: The analytical sample included 1250 participants. Physical activity peaked between ages 6.5-10.5 y, depending on metric. For all metrics the highest activity levels occurred in less active participants (3rd-50th percentile) and girls, 0.5 to 1.5 y earlier than more active peers, and boys, respectively. Irrespective of metric, boys were more active than girls (p < .001) and physical activity was lowest in the Y8&9 group, particularly when compared to the Y1&2 group (p < .001). CONCLUSIONS: Percentile reference values for average acceleration, intensity gradient, and MX metrics have utility in describing age- and sex-specific values for physical activity volume and intensity in youth. There is a need to generate nationally-representative wrist-acceleration population-referenced norms for these metrics to further facilitate health-related physical activity research and promotion.


Assuntos
Acelerometria , Punho , Humanos , Masculino , Adolescente , Feminino , Criança , Valores de Referência , Benchmarking , Exercício Físico , Inglaterra
5.
Proc Natl Acad Sci U S A ; 117(26): 14883-14889, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32541057

RESUMO

Sitting for prolonged periods of time impairs people's health. Prior research has mainly investigated sitting behavior on an aggregate level, for example, by analyzing total sitting time per day. By contrast, taking a dynamic approach, here we conceptualize sitting behavior as a continuous chain of sit-to-stand and stand-to-sit transitions. We use multilevel time-to-event analysis to analyze the timing of these transitions. We analyze ∼30,000 objectively measured posture transitions from 156 people during work time. Results indicate that the temporal dynamics of sit-to-stand transitions differ from stand-to-sit transitions, and that people are quicker to switch postures later in the workday, and quicker to stand up after having been more active in the recent hours. We found no evidence for associations with physical fitness. Altogether, these findings provide insights into the origins of people's stand-up and sit-down decisions, show that sitting behavior is fundamentally different from exercise behavior, and provide pointers for the development of interventions.


Assuntos
Postura/fisiologia , Comportamento Sedentário , Postura Sentada , Adulto , Feminino , Humanos , Masculino , Saúde Ocupacional , Aptidão Física , Fatores de Tempo , Local de Trabalho , Adulto Jovem
6.
J Biol Chem ; 297(5): 101335, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34688654

RESUMO

Oncogenic KRAS drives cancer growth by activating diverse signaling networks, not all of which have been fully delineated. We set out to establish a system-wide profile of the KRAS-regulated kinase signaling network (kinome) in KRAS-mutant pancreatic ductal adenocarcinoma (PDAC). We knocked down KRAS expression in a panel of six cell lines and then applied multiplexed inhibitor bead/MS to monitor changes in kinase activity and/or expression. We hypothesized that depletion of KRAS would result in downregulation of kinases required for KRAS-mediated transformation and in upregulation of other kinases that could potentially compensate for the deleterious consequences of the loss of KRAS. We identified 15 upregulated and 13 downregulated kinases in common across the panel of cell lines. In agreement with our hypothesis, all 15 of the upregulated kinases have established roles as cancer drivers (e.g., SRC, TGF-ß1, ILK), and pharmacological inhibition of one of these upregulated kinases, DDR1, suppressed PDAC growth. Interestingly, 11 of the 13 downregulated kinases have established driver roles in cell cycle progression, particularly in mitosis (e.g., WEE1, Aurora A, PLK1). Consistent with a crucial role for the downregulated kinases in promoting KRAS-driven proliferation, we found that pharmacological inhibition of WEE1 also suppressed PDAC growth. The unexpected paradoxical activation of ERK upon WEE1 inhibition led us to inhibit both WEE1 and ERK concurrently, which caused further potent growth suppression and enhanced apoptotic death compared with WEE1 inhibition alone. We conclude that system-wide delineation of the KRAS-regulated kinome can identify potential therapeutic targets for KRAS-mutant pancreatic cancer.


Assuntos
Carcinoma Ductal Pancreático , Proteínas de Ciclo Celular/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mutação , Neoplasias Pancreáticas , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/enzimologia , Carcinoma Ductal Pancreático/genética , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
7.
Br J Cancer ; 126(8): 1157-1167, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34912072

RESUMO

BACKGROUND: Excess adiposity at diagnosis and weight gain during chemotherapy is associated with tumour recurrence and chemotherapy toxicity. We assessed the efficacy of intermittent energy restriction (IER) vs continuous energy restriction (CER) for weight control and toxicity reduction during chemotherapy. METHODS: One hundred and seventy-two women were randomised to follow IER or CER throughout adjuvant/neoadjuvant chemotherapy. Primary endpoints were weight and body fat change. Secondary endpoints included chemotherapy toxicity, cardiovascular risk markers, and correlative markers of metabolism, inflammation and oxidative stress. RESULTS: Primary analyses showed non-significant reductions in weight (-1.1 (-2.4 to +0.2) kg, p = 0.11) and body fat (-1.0 (-2.1 to +0.1) kg, p = 0.086) in IER compared with CER. Predefined secondary analyses adjusted for body water showed significantly greater reductions in weight (-1.4 (-2.5 to -0.2) kg, p = 0.024) and body fat (-1.1 (-2.1 to -0.2) kg, p = 0.046) in IER compared with CER. Incidence of grade 3/4 toxicities were comparable overall (IER 31.0 vs CER 36.5%, p = 0.45) with a trend to fewer grade 3/4 toxicities with IER (18%) vs CER (31%) during cycles 4-6 of primarily taxane therapy (p = 0.063). CONCLUSIONS: IER is feasible during chemotherapy. The potential efficacy for weight control and reducing toxicity needs to be tested in future larger trials. CLINICAL TRIAL REGISTRATION: ISRCTN04156504.


Assuntos
Neoplasias da Mama , Dieta Redutora , Neoplasias da Mama/tratamento farmacológico , Restrição Calórica , Feminino , Humanos , Recidiva Local de Neoplasia , Obesidade
8.
J Biol Chem ; 295(24): 8195-8203, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32350113

RESUMO

The Ser/Thr protein kinase MELK (maternal embryonic leucine zipper kinase) has been considered an attractive therapeutic target for managing cancer since 2005. Studies using expression analysis have indicated that MELK expression is higher in numerous cancer cells and tissues than in their normal, nonneoplastic counterparts. Further, RNAi-mediated MELK depletion impairs proliferation of multiple cancers, including triple-negative breast cancer (TNBC), and these growth defects can be rescued with exogenous WT MELK, but not kinase-dead MELK complementation. Pharmacological MELK inhibition with OTS167 (alternatively called OTSSP167) and NVS-MELK8a, among other small molecules, also impairs cancer cell growth. These collective results led to MELK being classified as essential for cancer proliferation. More recently, in 2017, the proliferation of TNBC and other cancer cell lines was reported to be unaffected by genetic CRISPR/Cas9-mediated MELK deletion, calling into question the essentiality of this kinase in cancer. To date, the requirement of MELK in cancer remains controversial, and mechanisms underlying the disparate growth effects observed with RNAi, pharmacological inhibition, and CRISPR remain unclear. Our objective with this review is to highlight the evidence on both sides of this controversy, to provide commentary on the purported requirement of MELK in cancer, and to emphasize the need for continued elucidation of the functions of MELK.


Assuntos
Neoplasias/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Proliferação de Células , Humanos , Modelos Biológicos , Neoplasias/patologia
9.
J Biol Chem ; 295(17): 5654-5668, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32156701

RESUMO

Protein phosphatase 2A (PP2A) is a large enzyme family responsible for most cellular Ser/Thr dephosphorylation events. PP2A substrate specificity, localization, and regulation by second messengers rely on more than a dozen regulatory subunits (including B/R2, B'/R5, and B″/R3), which form the PP2A heterotrimeric holoenzyme by associating with a dimer comprising scaffolding (A) and catalytic (C) subunits. Because of partial redundancy and high endogenous expression of PP2A holoenzymes, traditional approaches of overexpressing, knocking down, or knocking out PP2A regulatory subunits have yielded only limited insights into their biological roles and substrates. To this end, here we sought to reduce the complexity of cellular PP2A holoenzymes. We used tetracycline-inducible expression of pairs of scaffolding and regulatory subunits with complementary charge-reversal substitutions in their interaction interfaces. For each of the three regulatory subunit families, we engineered A/B charge-swap variants that could bind to one another, but not to endogenous A and B subunits. Because endogenous Aα was targeted by a co-induced shRNA, endogenous B subunits were rapidly degraded, resulting in expression of predominantly a single PP2A heterotrimer composed of the A/B charge-swap pair and the endogenous catalytic subunit. Using B'δ/PPP2R5D, we show that PP2A complexity reduction, but not PP2A overexpression, reveals a role of this holoenzyme in suppression of extracellular signal-regulated kinase signaling and protein kinase A substrate dephosphorylation. When combined with global phosphoproteomics, the PP2A/B'δ reduction approach identified consensus dephosphorylation motifs in its substrates and suggested that residues surrounding the phosphorylation site play roles in PP2A substrate specificity.


Assuntos
Proteína Fosfatase 2/metabolismo , Animais , Células COS , Domínio Catalítico , Chlorocebus aethiops , Células HEK293 , Humanos , Modelos Moleculares , Fosforilação , Mapas de Interação de Proteínas , Multimerização Proteica , Proteína Fosfatase 2/análise , Subunidades Proteicas/análise , Subunidades Proteicas/metabolismo
10.
J Biol Chem ; 295(8): 2359-2374, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-31896573

RESUMO

The maternal embryonic leucine zipper kinase (MELK) has been implicated in the regulation of cancer cell proliferation. RNAi-mediated MELK depletion impairs growth and causes G2/M arrest in numerous cancers, but the mechanisms underlying these effects are poorly understood. Furthermore, the MELK inhibitor OTSSP167 has recently been shown to have poor selectivity for MELK, complicating the use of this inhibitor as a tool compound to investigate MELK function. Here, using a cell-based proteomics technique called multiplexed kinase inhibitor beads/mass spectrometry (MIB/MS), we profiled the selectivity of two additional MELK inhibitors, NVS-MELK8a (8a) and HTH-01-091. Our results revealed that 8a is a highly selective MELK inhibitor, which we further used for functional studies. Resazurin and crystal violet assays indicated that 8a decreases triple-negative breast cancer cell viability, and immunoblotting revealed that impaired growth is due to perturbation of cell cycle progression rather than induction of apoptosis. Using double-thymidine synchronization and immunoblotting, we observed that MELK inhibition delays mitotic entry, which was associated with delayed activation of Aurora A, Aurora B, and cyclin-dependent kinase 1 (CDK1). Following this delay, cells entered and completed mitosis. Using live-cell microscopy of cells harboring fluorescent proliferating cell nuclear antigen, we confirmed that 8a significantly and dose-dependently lengthens G2 phase. Collectively, our results provide a rationale for using 8a as a tool compound for functional studies of MELK and indicate that MELK inhibition delays mitotic entry, likely via transient G2/M checkpoint activation.


Assuntos
Espectrometria de Massas , Mitose , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Histonas/metabolismo , Humanos , Mitose/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Neoplasias de Mama Triplo Negativas/enzimologia , Neoplasias de Mama Triplo Negativas/patologia
11.
Int J Behav Nutr Phys Act ; 17(1): 75, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539720

RESUMO

BACKGROUND: Subjective measures of sedentary behaviour (SB) (i.e. questionnaires and diaries/logs) are widely implemented, and can be useful for capturing type and context of SBs. However, little is known about comparative validity and reliability. The aim of this systematic review and meta-analysis was to: 1) identify subjective methods to assess overall, domain- and behaviour-specific SB, and 2) examine the validity and reliability of these methods. METHODS: The databases MEDLINE, EMBASE and SPORTDiscus were searched up to March 2020. Inclusion criteria were: 1) assessment of SB, 2) evaluation of subjective measurement tools, 3) being performed in healthy adults, 4) manuscript written in English, and 5) paper was peer-reviewed. Data of validity and/or reliability measurements was extracted from included studies and a meta-analysis using random effects was performed to assess the pooled correlation coefficients of the validity. RESULTS: The systematic search resulted in 2423 hits. After excluding duplicates and screening on title and abstract, 82 studies were included with 75 self-reported measurement tools. There was wide variability in the measurement properties and quality of the studies. The criterion validity varied between poor-to-excellent (correlation coefficient [R] range - 0.01- 0.90) with logs/diaries (R = 0.63 [95%CI 0.48-0.78]) showing higher criterion validity compared to questionnaires (R = 0.35 [95%CI 0.32-0.39]). Furthermore, correlation coefficients of single- and multiple-item questionnaires were comparable (1-item R = 0.34; 2-to-9-items R = 0.35; ≥10-items R = 0.37). The reliability of SB measures was moderate-to-good, with the quality of these studies being mostly fair-to-good. CONCLUSION: Logs and diaries are recommended to validly and reliably assess self-reported SB. However, due to time and resources constraints, 1-item questionnaires may be preferred to subjectively assess SB in large-scale observations when showing similar validity and reliability compared to longer questionnaires. REGISTRATION NUMBER: CRD42018105994.


Assuntos
Prontuários Médicos/normas , Comportamento Sedentário , Inquéritos e Questionários/normas , Adulto , Humanos , Autorrelato
12.
J Proteome Res ; 18(1): 522-534, 2019 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-30540191

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease, and at least one-third of its patients relapse after treatment with the current chemotherapy regimen, R-CHOP. By gene-expression profiling, patients with DLBCL can be categorized into two clinically relevant subtypes: activated B-cell (ABC) and germinal center B-cell (GCB) DLBCL. Patients with the ABC subtype have a worse prognosis than those with GCB, and the subtype is defined by chronic, over-active signaling through the B-cell receptor and NF-κB pathways. We examined the effects of the Src family kinase (SFK) inhibitor dasatinib in a panel of ABC and GCB DLBCL cell lines and found that the former are much more sensitive to dasatinib than the latter. However, using multiplexed inhibitor bead coupled to mass spectrometry (MIB/MS) kinome profiling and Western blot analysis, we found that both subtypes display inhibition of the SFKs in response to dasatinib after both short- and long-term treatment. The MIB/MS analyses revealed that several cell-cycle kinases, including CDK4, CDK6, and the Aurora kinases, are down-regulated by dasatinib treatment in the ABC, but not in the GCB, subtype. The present findings have potential implications for the clinical use of dasatinib for the treatment of ABC DLBCL, either alone or in combination with other agents.


Assuntos
Dasatinibe/farmacologia , Centro Germinativo/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Antineoplásicos/uso terapêutico , Linfócitos B/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Dasatinibe/uso terapêutico , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Centro Germinativo/patologia , Humanos , Linfoma Difuso de Grandes Células B/classificação
13.
J Am Chem Soc ; 141(39): 15700-15709, 2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31497954

RESUMO

Controlling which particular members of a large protein family are targeted by a drug is key to achieving a desired therapeutic response. In this study, we report a rational data-driven strategy for achieving restricted polypharmacology in the design of antitumor agents selectively targeting the TYRO3, AXL, and MERTK (TAM) family tyrosine kinases. Our computational approach, based on the concept of fragments in structural environments (FRASE), distills relevant chemical information from structural and chemogenomic databases to assemble a three-dimensional inhibitor structure directly in the protein pocket. Target engagement by the inhibitors designed led to disruption of oncogenic phenotypes as demonstrated in enzymatic assays and in a panel of cancer cell lines, including acute lymphoblastic and myeloid leukemia (ALL/AML) and nonsmall cell lung cancer (NSCLC). Structural rationale underlying the approach was corroborated by X-ray crystallography. The lead compound demonstrated potent target inhibition in a pharmacodynamic study in leukemic mice.


Assuntos
Antineoplásicos/química , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Estrutura Molecular , Neoplasias Experimentais
14.
Artigo em Inglês | MEDLINE | ID: mdl-30917980

RESUMO

Alphaviruses are arthropod-transmitted RNA viruses that can cause arthralgia, myalgia, and encephalitis in humans. Since the role of cellular kinases in alphavirus replication is unknown, we profiled kinetic changes in host kinase abundance and phosphorylation following chikungunya virus (CHIKV) infection of fibroblasts. Based upon the results of this study, we treated CHIKV-infected cells with kinase inhibitors targeting the Src family kinase (SFK)-phosphatidylinositol 3-kinase (PI3K)-AKT-mTORC signaling pathways. Treatment of cells with SFK inhibitors blocked the replication of CHIKV as well as multiple other alphaviruses, including Mayaro virus, O'nyong-nyong virus, Ross River virus, and Venezuelan equine encephalitis virus. Dissecting the effect of SFK inhibition on alphavirus replication, we found that viral structural protein levels were significantly reduced, but synthesis of viral genomic and subgenomic RNAs was unaffected. By measuring the association of viral RNA with polyribosomes, we found that the SFK inhibitor dasatinib blocks alphavirus subgenomic RNA translation. Our results demonstrate a role for SFK signaling in alphavirus subgenomic RNA translation and replication. Targeting host factors involved in alphavirus replication represents an innovative, perhaps paradigm-shifting, strategy for exploring the replication of CHIKV and other alphaviruses while promoting antiviral therapeutic development.


Assuntos
Infecções por Alphavirus/tratamento farmacológico , Alphavirus/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/genética , Quinases da Família src/genética , Alphavirus/genética , Infecções por Alphavirus/virologia , Animais , Antivirais/farmacologia , Linhagem Celular , Chlorocebus aethiops , Genoma Viral/efeitos dos fármacos , Genoma Viral/genética , Humanos , Camundongos Knockout , Fosfatidilinositol 3-Quinases/genética , RNA Viral/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Células Vero , Proteínas Virais/genética , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
15.
FASEB J ; 32(7): 3892-3902, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29465311

RESUMO

Sustained endoplasmic reticulum (ER) stress plays a major role in the development of many metabolic diseases, including cardiovascular disease, nonalcoholic fatty liver disease, insulin resistance, obesity, and diabetes. p32 is a multicompartmental protein involved in the regulation of oxidative phosphorylation and glucose oxidation. p32 ablation is associated with resistance to age-associated and diet-induced obesity through a mechanism that remains largely unknown. Here, we show that p32 promotes lipid biosynthesis by modulating fatty acid-induced ER stress. We found that p32 interacts with endoplasmic reticulum-anchored enzyme mannosyl-oligosaccharide glucosidase I (GCS1), an ER lumen-anchored glucosidase that is essential for the processing of N-linked glycoproteins, and reduces GCS1 in a lysosome-dependent manner. We demonstrate that increased GCS1 expression alleviates fatty acid-induced ER stress and is critical for suppressing ER stress-associated lipogenic gene activation, as demonstrated by the down-regulation of Srebp1, Fasn, and Acc. Consistently, suppression of p32 leads to increased GCS1 expression and alleviates fatty acid-induced ER stress, resulting in reduced lipid accumulation. Thus, p32 and GCS1 are regulators of ER function and lipid homeostasis and are potential therapeutic targets for the treatment of obesity and diabetes.-Liu, Y., Leslie, P. L., Jin, A., Itahana, K., Graves, L. M., Zhang, Y. p32 regulates ER stress and lipid homeostasis by down-regulating GCS1 expression.


Assuntos
Estresse do Retículo Endoplasmático , Metabolismo dos Lipídeos , Proteínas Mitocondriais/metabolismo , alfa-Glucosidases/metabolismo , Células 3T3 , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Animais , Linhagem Celular Tumoral , Células Cultivadas , Regulação para Baixo , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Homeostase , Humanos , Camundongos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , alfa-Glucosidases/genética
16.
Mol Cell Proteomics ; 16(4 suppl 1): S263-S276, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28237943

RESUMO

Human cytomegalovirus (HCMV) is a significant cause of disease in immune-compromised adults and immune naïve newborns. No vaccine exists to prevent HCMV infection, and current antiviral therapies have toxic side effects that limit the duration and intensity of their use. There is thus an urgent need for new strategies to treat HCMV infection. Repurposing existing drugs as antivirals is an attractive approach to limit the time and cost of new antiviral drug development. Virus-induced changes in infected cells are often driven by changes in cellular kinase activity, which led us to hypothesize that defining the complement of kinases (the kinome), whose abundance or expression is altered during infection would identify existing kinase inhibitors that could be repurposed as new antivirals. To this end, we applied a kinase capture technique, multiplexed kinase inhibitor bead-mass spectrometry (MIB-MS) kinome, to quantitatively measure perturbations in >240 cellular kinases simultaneously in cells infected with a laboratory-adapted (AD169) or clinical (TB40E) HCMV strain. MIB-MS profiling identified time-dependent increases and decreases in MIB binding of multiple kinases including cell cycle kinases, receptor tyrosine kinases, and mitotic kinases. Based on the kinome data, we tested the antiviral effects of kinase inhibitors and other compounds, several of which are in clinical use or development. Using a novel flow cytometry-based assay and a fluorescent reporter virus we identified three compounds that inhibited HCMV replication with IC50 values of <1 µm, and at doses that were not toxic to uninfected cells. The most potent inhibitor of HCMV replication was OTSSP167 (IC50 <1.2 nm), a MELK inhibitor, blocked HCMV early gene expression and viral DNA accumulation, resulting in a >3 log decrease in virus replication. These results show the utility of MIB-MS kinome profiling for identifying existing kinase inhibitors that can potentially be repurposed as novel antiviral drugs.


Assuntos
Antivirais/farmacologia , Citomegalovirus/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Células Cultivadas , Citomegalovirus/metabolismo , Reposicionamento de Medicamentos , Humanos , Espectrometria de Massas/métodos , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
17.
Am J Respir Crit Care Med ; 198(1): 67-76, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29481290

RESUMO

RATIONALE: E-cigarettes vaporize propylene glycol/vegetable glycerin (PG/VG), nicotine, and flavorings. However, the long-term health effects of exposing lungs to vaped e-liquids are unknown. OBJECTIVES: To determine the effects of chronic vaping on pulmonary epithelia. METHODS: We performed research bronchoscopies on healthy nonsmokers, cigarette smokers, and e-cigarette users (vapers) and obtained bronchial brush biopsies and lavage samples from these subjects for proteomic investigation. We further employed in vitro and murine exposure models to support our human findings. MEASUREMENTS AND MAIN RESULTS: Visual inspection by bronchoscopy revealed that vaper airways appeared friable and erythematous. Epithelial cells from biopsy samples revealed approximately 300 proteins that were differentially expressed in smoker and vaper airways, with only 78 proteins being commonly altered in both groups and 113 uniquely altered in vapers. For example, CYP1B1 (cytochrome P450 family 1 subfamily B member 1), MUC5AC (mucin 5 AC), and MUC4 levels were increased in vapers. Aerosolized PG/VG alone significantly increased MUC5AC protein in human airway epithelial cultures and in murine nasal epithelia in vivo. We also found that e-liquids rapidly entered cells and that PG/VG reduced membrane fluidity and impaired protein diffusion. CONCLUSIONS: We conclude that chronic vaping exerts marked biological effects on the lung and that these effects may in part be mediated by the PG/VG base. These changes are likely not harmless and may have clinical implications for the development of chronic lung disease. Further studies will be required to determine the full extent of vaping on the lung.


Assuntos
Brônquios/efeitos dos fármacos , Sistemas Eletrônicos de Liberação de Nicotina , Células Epiteliais/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nicotina/efeitos adversos , Proteoma/efeitos dos fármacos , Fumantes , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
BMC Public Health ; 19(1): 292, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30866872

RESUMO

BACKGROUND: Call agents spend ~ 90% of their working day seated, which may negatively impact health, productivity, and wellbeing. This study aimed to explore the acceptability and feasibility of a multi-component workplace intervention targeting increased activity and decreased prolonged sitting in the contact centre setting prior to a full-scale effectiveness trial. METHODS: An 8-week non-randomised pre-post feasibility study was conducted. Using a mixed methods approach, focus groups and interviews were thematically analysed to explore the acceptability and feasibility of key study phases, and provide context to agents' process evaluation and survey responses. The multi-component intervention, conducted in a single call centre, included height-adjustable workstations, emails, education and training sessions, and support from team leaders and a workplace champion. RESULTS: Six (of 20) team leaders were recruited, with 17 of 84 call agents (78% female, 39.3 ± 11.9 years) completing baseline assessments and 13 completing follow-up. High workload influenced recruitment. Call agents perceived assessments as acceptable, though strategies are needed to enhance fidelity. Education sessions, height-adjustable workstations and emails were perceived as the most effective components; however, height-adjustable hot-desks were not perceived as feasible in this setting. CONCLUSIONS: This study has identified unique, pragmatic considerations for conducting a multi-level, multi-component PA and SB intervention and associated evaluation in highly sedentary call agents in the challenging contact centre setting. The intervention was largely perceived positively, with call agents and team leaders describing numerous perceived positive effects on behavioural, health and work-related outcomes. Findings will be of value to researchers attempting to intervene in contact centres and will be used by the current authors to design a subsequent trial.


Assuntos
Call Centers , Exercício Físico , Promoção da Saúde/métodos , Saúde Ocupacional , Postura Sentada , Adulto , Estudos de Viabilidade , Feminino , Grupos Focais , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Comportamento Sedentário , Inquéritos e Questionários
19.
Health Promot Int ; 34(5): 931-940, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30011015

RESUMO

Formative research is an important first step in the design and development of children's school-based physical activity (PA) interventions. Exploration of educator [headteacher and physical education (PE)-co-ordinator] perceptions toward the promotion of school-based PA, including PE delivery has however been limited. This study took a socio-ecological approach to explore the barriers and facilitators of children's school-based PA from the perspective of school educators. Interviews were conducted with headteachers (n = 4), PE-co-ordinators (n = 4) and a deputy headteacher (n = 1) and data thematically analysed using Nvivo software (version 10). Findings suggested that, at an organizational level headteachers were the predominant driving force in the promotion of PA opportunities, yet institutional barriers including low priority for PA and PE were perceived to negate delivery. At an interpersonal level, strategies to increase the delivery of school-based PA were developed, however poor teacher-coach relationships and significant others reduced PA promotion opportunities. Child PA was further negated through intrapersonal factors, including lack of PE-specific teacher training and varying teacher interest in PA and sport. To increase primary school children's school-based PA, barriers and facilitators at the organizational, interpersonal and intrapersonal level must be considered and targeted and researchers and schools should work in partnership to develop future interventions.


Assuntos
Pessoal de Educação/psicologia , Exercício Físico , Serviços de Saúde Escolar/organização & administração , Adulto , Criança , Inglaterra , Feminino , Humanos , Masculino , Educação Física e Treinamento/métodos , Educação Física e Treinamento/organização & administração , Instituições Acadêmicas/organização & administração , Capacitação de Professores
20.
Plant J ; 89(2): 416-426, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27671103

RESUMO

The identification of dynamic protein phosphorylation events is critical for understanding kinase/phosphatase-regulated signaling pathways. To date, protein phosphorylation and kinase expression have been examined independently in photosynthetic organisms. Here we present a method to study the global kinome and phosphoproteome in tandem in a model photosynthetic organism, the alga Chlamydomonas reinhardtii (Chlamydomonas), using mass spectrometry-based label-free proteomics. A dual enrichment strategy targets intact protein kinases via capture on immobilized multiplexed inhibitor beads with subsequent proteolytic digestion of unbound proteins and peptide-based phosphorylation enrichment. To increase depth of coverage, both data-dependent and data-independent (via SWATH, Sequential Windowed Acquisition of All Theoretical Fragment Ion Mass Spectra) mass spectrometric acquisitions were performed to obtain a more than 50% increase in coverage of the enriched Chlamydomonas kinome over coverage found with no enrichment. The quantitative phosphoproteomic dataset yielded 2250 phosphopeptides and 1314 localized phosphosites with excellent reproducibility across biological replicates (90% of quantified sites with coefficient of variation below 11%). This approach enables simultaneous investigation of kinases and phosphorylation events at the global level to facilitate understanding of kinase networks and their influence in cell signaling events.


Assuntos
Chlamydomonas reinhardtii/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Quinases/metabolismo , Proteômica/métodos , Parede Celular/química , Fracionamento Químico , Espectrometria de Massas/métodos , Fosfoproteínas/análise , Proteínas de Plantas/análise , Proteínas de Plantas/isolamento & purificação , Proteínas Quinases/análise , Reprodutibilidade dos Testes
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