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Tumor-homing neural stem cell (NSC) therapy is emerging as a promising treatment for aggressive cancers of the brain. Despite their success, developing tumor-homing NSC therapy therapies that maintain durable tumor suppression remains a challenge. Herein, we report a synergistic combination regimen where the novel small molecule TR-107 augments NSC-tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) therapy (hiNeuroS-TRAIL) in models of the incurable brain cancer glioblastoma (GBM) in vitro. We report that the combination of hiNeuroS-TRAIL and TR-107 synergistically upregulated caspase markers and restored sensitivity to the intrinsic apoptotic pathway by significantly downregulating inhibitory pathways associated with chemoresistance and radioresistance in the TRAIL-resistant LN229 cell line. This combination also showed robust tumor suppression and enhanced survival of mice bearing human xenografts of both solid and invasive GBMs. These findings elucidate a novel combination regimen and suggest that the combination of these clinically relevant agents may represent a new therapeutic option with increased efficacy for patients with GBM.
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How the KRAS oncogene drives cancer growth remains poorly understood. Therefore, we established a systemwide portrait of KRAS- and extracellular signal-regulated kinase (ERK)-dependent gene transcription in KRAS-mutant cancer to delineate the molecular mechanisms of growth and of inhibitor resistance. Unexpectedly, our KRAS-dependent gene signature diverges substantially from the frequently cited Hallmark KRAS signaling gene signature, is driven predominantly through the ERK mitogen-activated protein kinase (MAPK) cascade, and accurately reflects KRAS- and ERK-regulated gene transcription in KRAS-mutant cancer patients. Integration with our ERK-regulated phospho- and total proteome highlights ERK deregulation of the anaphase promoting complex/cyclosome (APC/C) and other components of the cell cycle machinery as key processes that drive pancreatic ductal adenocarcinoma (PDAC) growth. Our findings elucidate mechanistically the critical role of ERK in driving KRAS-mutant tumor growth and in resistance to KRAS-ERK MAPK targeted therapies.
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Carcinoma Ductal Pancreático , Quinasas MAP Reguladas por Señal Extracelular , Regulación Neoplásica de la Expresión Génica , Sistema de Señalización de MAP Quinasas , Mutación , Neoplasias Pancreáticas , Proteínas Proto-Oncogénicas p21(ras) , Transcriptoma , Animales , Humanos , Ratones , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/metabolismo , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Células HEK293RESUMEN
To delineate the mechanisms by which the ERK1 and ERK2 mitogen-activated protein kinases support mutant KRAS-driven cancer growth, we determined the ERK-dependent phosphoproteome in KRAS-mutant pancreatic cancer. We determined that ERK1 and ERK2 share near-identical signaling and transforming outputs and that the KRAS-regulated phosphoproteome is driven nearly completely by ERK. We identified 4666 ERK-dependent phosphosites on 2123 proteins, of which 79 and 66%, respectively, were not previously associated with ERK, substantially expanding the depth and breadth of ERK-dependent phosphorylation events and revealing a considerably more complex function for ERK in cancer. We established that ERK controls a highly dynamic and complex phosphoproteome that converges on cyclin-dependent kinase regulation and RAS homolog guanosine triphosphatase function (RHO GTPase). Our findings establish the most comprehensive molecular portrait and mechanisms by which ERK drives KRAS-dependent pancreatic cancer growth.
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Proteína Quinasa 1 Activada por Mitógenos , Proteína Quinasa 3 Activada por Mitógenos , Neoplasias Pancreáticas , Fosfoproteínas , Proteoma , Proteínas Proto-Oncogénicas p21(ras) , Animales , Humanos , Ratones , Línea Celular Tumoral , Quinasas Ciclina-Dependientes/metabolismo , Quinasas Ciclina-Dependientes/genética , Sistema de Señalización de MAP Quinasas , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Mutación , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Fosforilación , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Células HEK293RESUMEN
BACKGROUND: Cardiac rehabilitation has been identified as having the most homogenous clinical exercise service structure in the United Kingdom (UK), but inconsistencies are evident in staff roles and qualifications within and across services. The recognition of Clinical Exercise Physiologists (CEPs) as a registered health professional in 2021 in the UK, provides a potential solution to standardise the cardiac rehabilitation workforce. This case study examined, in a purposefully selected cardiac exercise service that employed registered CEPs, (i) how staff knowledge, skills and competencies contribute to the provision of the service, (ii) how these components assist in creating effective service teams, and (iii) the existing challenges from staff and patient perspectives. METHODS: A multi-method qualitative approach (inc., semi-structured interviews, observations, field notes and researcher reflections) was employed with the researcher immersed for 12-weeks within the service. The Consolidated Framework for Implementation Research was used as an overarching guide for data collection. Data derived from registered CEPs (n = 5), clinical nurse specialists (n = 2), dietitians (n = 1), service managers/leads (n = 2) and patients (n = 7) were thematically analysed. RESULTS: Registered CEPs delivered innovative exercise prescription based on their training, continued professional development (CPD), academic qualifications and involvement in research studies as part of the service. Exposure to a wide multidisciplinary team (MDT) allowed skill and competency transfer in areas such as clinical assessments. Developing an effective behaviour change strategy was challenging with delivery of lifestyle information more effective during less formal conversations compared to timetabled education sessions. CONCLUSIONS: Registered CEPs have the specialist knowledge and skills to undertake and implement the latest evidence-based exercise prescription in a cardiac rehabilitation setting. An MDT service structure enables a more effective team upskilling through shared peer experiences, observations and collaborative working between healthcare professionals.
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PURPOSE: Social determinants of health and poor working conditions contribute to excessive sickness absence and attrition in contact centre advisors. With no recent review conducted, the current scoping review is needed to investigate the volume, effectiveness, acceptability, and feasibility of health-promoting interventions for contact centre advisors. This will inform the adoption and implementation of evidence-based practice, and future research. METHODS: Searches conducted across four databases (MEDLINE, PsycInfo, CINAHL, Web of Science) and reference checking in February 2023 identified health-promoting interventions for contact centre advisors. Extracted and coded data from eligible interventions were systematically synthesised using the nine intervention functions of the Behaviour Change Wheel and behaviour change technique taxonomy. RESULTS: This scoping review identified a low number of high quality and peer-reviewed health-promoting intervention studies for contact centre advisors (28 studies since 2002). Most interventions were conducted in high-income countries with office-based advisors, predominantly using environmental restructuring and training strategies to improve health. Most interventions reported positive effectiveness results for the primary intended outcomes, which were broadly organised into: i) health behaviours (sedentary behaviour, physical activity, smoking); ii) physical health outcomes (musculoskeletal health, visual health, vocal health, sick building syndrome); iii) mental health outcomes (stress, job control, job satisfaction, wellbeing). Few interventions evaluated acceptability and feasibility. CONCLUSION: There is little evidence on the effectiveness, acceptability, and feasibility of health-promoting interventions for contact centre advisors. Evidence is especially needed in low-to-middle income countries, and for remote/hybrid, nightshift, older and disabled advisors.
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Ejercicio Físico , Promoción de la Salud , Salud Laboral , Humanos , Terapia Conductista , Conducta SedentariaRESUMEN
Pancreatic cancer is one of the leading causes of cancer deaths, with pancreatic ductal adenocarcinoma (PDAC) being the most common subtype. Advanced stage diagnosis of PDAC is common, causing limited treatment opportunities. Gemcitabine is a frequently used chemotherapeutic agent which can be used as a monotherapy or in combination. However, tumors often develop resistance to gemcitabine. Previous studies show that the proto-oncogene PIM kinases (PIM1 and PIM3) are upregulated in PDAC compared to matched normal tissue and are related to chemoresistance and PDAC cell growth. The PIM kinases are also involved in the PI3K/AKT/mTOR pathway to promote cell survival. In this study, we evaluate the effect of the novel multikinase PIM/PI3K/mTOR inhibitor, AUM302, and commercially available PIM inhibitor, TP-3654. Using five human PDAC cell lines, we found AUM302 to be a potent inhibitor of cell proliferation, cell viability, cell cycle progression, and phosphoprotein expression, while TP-3654 was less effective. Significantly, AUM302 had a strong impact on the viability of gemcitabine-resistant PDAC cells. Taken together, these results demonstrate that AUM302 exhibits antitumor activity in human PDAC cells and thus has the potential to be an effective drug for PDAC therapy.
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Antineoplásicos , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Crecimiento/farmacología , Neoplasias Pancreáticas/patología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Carcinoma Ductal Pancreático/patología , Gemcitabina , Serina-Treonina Quinasas TOR , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Proliferación Celular , Línea Celular TumoralRESUMEN
Antimicrobial resistance (AMR) is widely acknowledged as one of the most serious public health threats facing the world, yet the private sector finds it challenging to generate much-needed medicines. As an alternative discovery approach, a small array of diarylimidazoles was screened against the ESKAPE pathogens, and the results were made publicly available through the Open Source Antibiotics (OSA) consortium (https://github.com/opensourceantibiotics). Of the 18 compounds tested (at 32 µg/mL), 15 showed >90% growth inhibition activity against methicillin-resistant Staphylococcus aureus (MRSA) alone. In the subsequent hit-to-lead optimization of this chemotype, 147 new heterocyclic compounds containing the diarylimidazole and other core motifs were synthesized and tested against MRSA, and their structure-activity relationships were identified. While potent, these compounds have moderate to high intrinsic clearance and some associated toxicity. The best overall balance of parameters was found with OSA_975, a compound with good potency, good solubility, and reduced intrinsic clearance in rat hepatocytes. We have progressed toward the knowledge of the molecular target of these phenotypically active compounds, with proteomic techniques suggesting TGFBR1 is potentially involved in the mechanism of action. Further development of these compounds toward antimicrobial medicines is available to anyone under the licensing terms of the project.
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Antibacterianos , Staphylococcus aureus Resistente a Meticilina , Ratas , Animales , Antibacterianos/farmacología , Proteómica , Pruebas de Sensibilidad Microbiana , Relación Estructura-ActividadRESUMEN
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.
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COVID-19 , Hepatitis C Crónica , Coronavirus del Síndrome Respiratorio de Oriente Medio , Humanos , Antivirales/farmacología , Inhibidores mTOR , Fosfatidilinositol 3-Quinasas , SARS-CoV-2 , Replicación Viral , Coronavirus del Síndrome Respiratorio de Oriente Medio/fisiología , Serina-Treonina Quinasas TORRESUMEN
PURPOSE: Clinical exercise delivery in the United Kingdom is disparate in terms of service structure, staff roles and qualifications, therefore it is difficult to evaluate and compare across services. Our aim was to explore, in a purposely selected cancer exercise service that was recognised as effective; (i) how staff knowledge, skills and competencies contribute to the provision of the service, (ii) how these components assist in creating effective services, and (iii) to identify existing challenges from staff and service user perspectives. METHODS: The Consolidated Framework for Implementation Research was used as an overarching guide to review the Prehab4Cancer service. Exercise specialists and service user perspectives were explored using a multi-method approach (online semi-structured interviews, online focus group and in-person observation) and data triangulation. RESULTS: Exercise specialists were educated to a minimum of undergraduate degree level with extensive cancer-specific knowledge and skills, equivalent to that of a Registration Council for Exercise Physiologist (RCCP) Clinical Exercise Physiologist. Workplace experience was essential for exercise specialist development in behaviour change and communications skills. CONCLUSIONS: Staff should be educated to a level comparable with the standards for registered RCCP Clinical Exercise Physiologists, which includes workplace experience to develop knowledge, skills and competencies in real-world settings.
Cancer servicesClinical exercise staff should attain extensive cancer-specific knowledge, skills and competencies, underpinned by undergraduate degrees in sport and exercise science-related subjects or higher and equivalent to that of Registration Council for Exercise Physiologist -registered Clinical ExerciseWorkplace experience is vital for exercise specialists to develop their knowledge, skills and competencies in real-world settings.Behaviour change and communication skills, specifically empathy and listening skills, should be incorporated into clinical exercise practitioner training.
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Transcription of the mitochondrial genome is essential for the maintenance of oxidative phosphorylation (OXPHOS) and other functions directly related to this unique genome. Considerable evidence suggests that mitochondrial transcription is dysregulated in cancer and cancer metastasis and contributes significantly to cancer cell metabolism. Recently, inhibitors of the mitochondrial DNA-dependent RNA polymerase (POLRMT) were identified as potentially attractive new anti-cancer compounds. These molecules (IMT1, IMT1B) inactivate cancer cell metabolism through reduced transcription of mitochondrially-encoded OXPHOS subunits such as ND1-5 (Complex I) and COI-IV (Complex IV). Studies from our lab have discovered small molecule regulators of the mitochondrial matrix caseinolytic protease (ClpP) as probable inhibitors of mitochondrial transcription. These compounds activate ClpP proteolysis and lead to the rapid depletion of POLRMT and other matrix proteins, resulting in inhibition of mitochondrial transcription and growth arrest. Herein we present a comparison of POLRMT inhibition and ClpP activation, both conceptually and experimentally, and evaluate the results of these treatments on mitochondrial transcription, inhibition of OXPHOS, and ultimately cancer cell growth. We discuss the potential for targeting mitochondrial transcription as a cancer cell vulnerability.
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Among all RNA viruses, coronavirus RNA transcription is the most complex and involves a process termed "discontinuous transcription" that results in the production of a set of 3'-nested, co-terminal genomic and subgenomic RNAs during infection. While the expression of the classic canonical set of subgenomic RNAs depends on the recognition of a 6- to 7-nt transcription regulatory core sequence (TRS), here, we use deep sequence and metagenomics analysis strategies and show that the coronavirus transcriptome is even more vast and more complex than previously appreciated and involves the production of leader-containing transcripts that have canonical and noncanonical leader-body junctions. Moreover, by ribosome protection and proteomics analyses, we show that both positive- and negative-sense transcripts are translationally active. The data support the hypothesis that the coronavirus proteome is much vaster than previously noted in the literature.
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Functional precision medicine platforms are emerging as promising strategies to improve pre-clinical drug testing and guide clinical decisions. We have developed an organotypic brain slice culture (OBSC)-based platform and multi-parametric algorithm that enable rapid engraftment, treatment, and analysis of uncultured patient brain tumor tissue and patient-derived cell lines. The platform has supported engraftment of every patient tumor tested to this point: high- and low-grade adult and pediatric tumor tissue rapidly establishes on OBSCs among endogenous astrocytes and microglia while maintaining the tumor's original DNA profile. Our algorithm calculates dose-response relationships of both tumor kill and OBSC toxicity, generating summarized drug sensitivity scores on the basis of therapeutic window and allowing us to normalize response profiles across a panel of U.S. Food and Drug Administration (FDA)-approved and exploratory agents. Summarized patient tumor scores after OBSC treatment show positive associations to clinical outcomes, suggesting that the OBSC platform can provide rapid, accurate, functional testing to ultimately guide patient care.
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Neoplasias Encefálicas , Humanos , Niño , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , EncéfaloRESUMEN
ClpP activators ONC201 and related small molecules (TR compounds, Madera Therapeutics), have demonstrated significant anti-cancer potential in vitro and in vivo studies, including clinical trials for refractory solid tumors. Though progress has been made in identifying specific phenotypic outcomes following ClpP activation, the exact mechanism by which ClpP activation leads to broad anti-cancer activity has yet to be fully elucidated. In this study, we utilized a multi-omics approach to identify the ClpP-dependent proteomic, transcriptomic, and metabolomic changes resulting from ONC201 or the TR compound TR-57 in triple-negative breast cancer cells. Applying mass spectrometry-based methods of proteomics and metabolomics, we identified â¼8,000 proteins and 588 metabolites, respectively. From proteomics data, 113 (ONC201) and 191 (TR-57) proteins significantly increased and 572 (ONC201) and 686 (TR-57) proteins significantly decreased in this study. Gene ontological (GO) analysis revealed strong similarities between proteins up- or downregulated by ONC201 or TR-57 treatment. Notably, this included the downregulation of many mitochondrial processes and proteins, including mitochondrial translation and mitochondrial matrix proteins. We performed a large-scale transcriptomic analysis of WT SUM159 cells, identifying â¼7,700 transcripts (746 and 1,100 significantly increasing, 795 and 1,013 significantly decreasing in ONC201 and TR-57 treated cells, respectively). Less than 21% of these genes were affected by these compounds in ClpP null cells. GO analysis of these data demonstrated additional similarity of response to ONC201 and TR-57, including a decrease in transcripts related to the mitochondrial inner membrane and matrix, cell cycle, and nucleus, and increases in other nuclear transcripts and transcripts related to metal-ion binding. Comparison of response between both compounds demonstrated a highly similar response in all -omics datasets. Analysis of metabolites also revealed significant similarities between ONC201 and TR-57 with increases in α-ketoglutarate and 2-hydroxyglutaric acid and decreased ureidosuccinic acid, L-ascorbic acid, L-serine, and cytidine observed following ClpP activation in TNBC cells. Further analysis identified multiple pathways that were specifically impacted by ClpP activation, including ATF4 activation, heme biosynthesis, and the citrulline/urea cycle. In summary the results of our studies demonstrate that ONC201 and TR-57 induce highly similar and broad effects against multiple mitochondrial processes required for cell proliferation.
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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.
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Acelerometría , Muñeca , Humanos , Masculino , Adolescente , Femenino , Niño , Valores de Referencia , Benchmarking , Ejercicio Físico , InglaterraRESUMEN
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.
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Neoplasias de la Mama , Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Programas de Reducción de Peso , Humanos , Femenino , Sobrepeso/terapia , Programas de Reducción de Peso/métodos , Neoplasias de la Mama/prevención & control , Obesidad/prevención & control , Pérdida de PesoRESUMEN
The mitochondrial ClpP protease is responsible for mitochondrial protein quality control through specific degradation of proteins involved in several metabolic processes. ClpP overexpression is also required in many cancer cells to eliminate reactive oxygen species (ROS)-damaged proteins and to sustain oncogenesis. Targeting ClpP to dysregulate its function using small-molecule agonists is a recent strategy in cancer therapy. Here, we synthesized imipridone-derived compounds and related chemicals, which we characterized using biochemical, biophysical, and cellular studies. Using X-ray crystallography, we found that these compounds have enhanced binding affinities due to their greater shape and charge complementarity with the surface hydrophobic pockets of ClpP. N-terminome profiling of cancer cells upon treatment with one of these compounds revealed the global proteomic changes that arise and identified the structural motifs preferred for protein cleavage by compound-activated ClpP. Together, our studies provide the structural and molecular basis by which dysregulated ClpP affects cancer cell viability and proliferation.
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Mitocondrias , Proteómica , Mitocondrias/metabolismo , Endopeptidasa Clp/genética , Endopeptidasa Clp/metabolismo , ProteolisisRESUMEN
Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a childhood-onset cerebellar ataxia caused by mutations in SACS, which encodes the protein sacsin. Cellular ARSACS phenotypes include mitochondrial dysfunction, intermediate filament disorganization, and progressive death of cerebellar Purkinje neurons. It is unclear why the loss of sacsin causes these deficits or why they manifest as cerebellar ataxia. Here, we perform multi-omic profiling in sacsin knockout (KO) cells and identify alterations in microtubule dynamics and mislocalization of focal adhesion (FA) proteins, including multiple integrins. Deficits in FA structure, signaling, and function can be rescued by targeting PTEN, a negative regulator of FA signaling. ARSACS mice possess mislocalization of ITGA1 in Purkinje neurons and synaptic disorganization in the deep cerebellar nucleus (DCN). The sacsin interactome reveals that sacsin regulates interactions between cytoskeletal and synaptic adhesion proteins. Our findings suggest that disrupted trafficking of synaptic adhesion proteins is a causal molecular deficit in ARSACS.
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Ataxia Cerebelosa , Ratones , Animales , Integrinas/genética , Proteínas de Choque Térmico/metabolismo , Ataxia/genética , MutaciónRESUMEN
Mitochondria are multifaceted organelles which are important for bioenergetics, biosynthesis and signaling in metazoans. Mitochondrial functions are frequently altered in cancer to promote both the energy and the necessary metabolic intermediates for biosynthesis required for tumor growth. Cancer stem cells (CSCs) contribute to chemotherapy resistance, relapse, and metastasis. Recent studies have shown that while non-stem, bulk cancer cells utilize glycolysis, breast CSCs are more dependent on oxidative phosphorylation (OxPhos) and therefore targeting mitochondria may inhibit CSC function. We previously reported that small molecule ONC201, which is an agonist for the mitochondrial caseinolytic protease (ClpP), induces mitochondrial dysfunction in breast cancer cells. In this study, we report that ClpP agonists inhibit breast cancer cell proliferation and CSC function in vitro and in vivo. Mechanistically, we found that OxPhos inhibition downregulates multiple pathways required for CSC function, such as the mevalonate pathway, YAP, Myc, and the HIF pathway. ClpP agonists showed significantly greater inhibitory effect on CSC functions compared with other mitochondria-targeting drugs. Further studies showed that ClpP agonists deplete NAD(P)+ and NAD(P)H, induce redox imbalance, dysregulate one-carbon metabolism and proline biosynthesis. Downregulation of these pathways by ClpP agonists further contribute to the inhibition of CSC function. In conclusion, ClpP agonists inhibit breast CSC functions by disrupting mitochondrial homeostasis in breast cancer cells and inhibiting multiple pathways critical to CSC function. Significance: ClpP agonists disrupt mitochondrial homeostasis by activating mitochondrial matrix protease ClpP. We report that ClpP agonists inhibit cell growth and cancer stem cell functions in breast cancer models by modulating multiple metabolic pathways essential to cancer stem cell function.
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Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Péptido Hidrolasas/metabolismo , NAD/metabolismo , Recurrencia Local de Neoplasia/metabolismo , Mitocondrias , Homeostasis , Endopeptidasas/metabolismo , Células Madre Neoplásicas , Endopeptidasa Clp/metabolismoRESUMEN
Cytomegalovirus (CMV) reactivation from latency following immune dysregulation remains a serious risk for patients, often causing substantial morbidity and mortality. Here, we demonstrate the CMV-encoded G protein-coupled receptor, US28, in coordination with cellular Ephrin receptor A2, attenuates mitogen-activated protein kinase signaling, thereby limiting viral replication in latently infected primary monocytes. Furthermore, treatment of latently infected primary monocytes with dasatinib, a Food and Drug Association-approved kinase inhibitor used to treat a subset of leukemias, results in CMV reactivation. These ex vivo data correlate with our retrospective analyses of the Explorys electronic health record database, where we find dasatinib treatment is associated with a significant risk of CMV-associated disease (odds ratio 1.58, P = 0.0004). Collectively, our findings elucidate a signaling pathway that plays a central role in the balance between CMV latency and reactivation and identifies a common therapeutic cancer treatment that elevates the risk of CMV-associated disease.
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We recently described the identification of a new class of small-molecule activators of the mitochondrial protease ClpP. These compounds synthesized by Madera Therapeutics showed increased potency of cancer growth inhibition over the related compound ONC201. In this study, we describe chemical optimization and characterization of the next generation of highly potent and selective small-molecule ClpP activators (TR compounds) and demonstrate their efficacy against breast cancer models in vitro and in vivo. We selected one compound (TR-107) with excellent potency, specificity, and drug-like properties for further evaluation. TR-107 showed ClpP-dependent growth inhibition in the low nanomolar range that was equipotent to paclitaxel in triple-negative breast cancer (TNBC) cell models. TR-107 also reduced specific mitochondrial proteins, including OXPHOS and TCA cycle components, in a time-, dose-, and ClpP-dependent manner. Seahorse XF analysis and glucose deprivation experiments confirmed the inactivation of OXPHOS and increased dependence on glycolysis following TR-107 exposure. The pharmacokinetic properties of TR-107 were compared with other known ClpP activators including ONC201 and ONC212. TR-107 displayed excellent exposure and serum t1/2 after oral administration. Using human TNBC MDA-MB-231 xenografts, the antitumor response to TR-107 was investigated. Oral administration of TR-107 resulted in a reduction in tumor volume and extension of survival in the treated compared with vehicle control mice. ClpP activation in vivo was validated by immunoblotting for TFAM and other mitochondrial proteins. In summary, we describe the identification of highly potent new ClpP agonists with improved efficacy against TNBC, through targeted inactivation of OXPHOS and disruption of mitochondrial metabolism.