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1.
Cancer Res ; 84(11): 1834-1855, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38831751

RESUMEN

Cancer cells exhibit metabolic plasticity to meet oncogene-driven dependencies while coping with nutrient availability. A better understanding of how systemic metabolism impacts the accumulation of metabolites that reprogram the tumor microenvironment (TME) and drive cancer could facilitate development of precision nutrition approaches. Using the Hi-MYC prostate cancer mouse model, we demonstrated that an obesogenic high-fat diet (HFD) rich in saturated fats accelerates the development of c-MYC-driven invasive prostate cancer through metabolic rewiring. Although c-MYC modulated key metabolic pathways, interaction with an obesogenic HFD was necessary to induce glycolysis and lactate accumulation in tumors. These metabolic changes were associated with augmented infiltration of CD206+ and PD-L1+ tumor-associated macrophages (TAM) and FOXP3+ regulatory T cells, as well as with the activation of transcriptional programs linked to disease progression and therapy resistance. Lactate itself also stimulated neoangiogenesis and prostate cancer cell migration, which were significantly reduced following treatment with the lactate dehydrogenase inhibitor FX11. In patients with prostate cancer, high saturated fat intake and increased body mass index were associated with tumor glycolytic features that promote the infiltration of M2-like TAMs. Finally, upregulation of lactate dehydrogenase, indicative of a lactagenic phenotype, was associated with a shorter time to biochemical recurrence in independent clinical cohorts. This work identifies cooperation between genetic drivers and systemic metabolism to hijack the TME and promote prostate cancer progression through oncometabolite accumulation. This sets the stage for the assessment of lactate as a prognostic biomarker and supports strategies of dietary intervention and direct lactagenesis blockade in treating advanced prostate cancer. SIGNIFICANCE: Lactate accumulation driven by high-fat diet and MYC reprograms the tumor microenvironment and promotes prostate cancer progression, supporting the potential of lactate as a biomarker and therapeutic target in prostate cancer. See related commentary by Frigo, p. 1742.


Asunto(s)
Dieta Alta en Grasa , Ácido Láctico , Obesidad , Neoplasias de la Próstata , Proteínas Proto-Oncogénicas c-myc , Microambiente Tumoral , Masculino , Animales , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/metabolismo , Dieta Alta en Grasa/efectos adversos , Ratones , Humanos , Ácido Láctico/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Obesidad/metabolismo , Obesidad/patología , Línea Celular Tumoral , Ratones Endogámicos C57BL , Macrófagos Asociados a Tumores/metabolismo
2.
Vaccines (Basel) ; 11(11)2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-38006027

RESUMEN

The extraordinary vaccination campaigns of the COVID-19 pandemic era put organizational and operational systems to the test in numerous territorial contexts. In the Veneto region, the activation of population vaccination centers (CVPs) guaranteed the provision of vaccines to mountain areas. These centers, drive-in and building-based, improved the efficiency of dose administration in relation to similar conditions where healthcare workers (HCWs) were routinely involved in clinics. Overall, a comparison of the two models investigated, with the same numbers of HCWs involved and the same opening hours for the vaccination sites, has shown that the CVPs are able to guarantee three times as many vaccines administered, compared with the traditional outpatient model. This study aims to provide a detailed analysis of the adopted organizational model, highlighting the best practices and improvements required to guarantee a timely and effective public health response, and evaluating the opportunities to deploy these innovative methods actively in a standard context.

3.
Vaccines (Basel) ; 11(4)2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37112669

RESUMEN

HPV is the most common cause of sexually-transmitted infections the world over. The aim of this study was to assess the impact of a healthcare quality improvement strategy designed to increase the rate of vaccination against HPV in women diagnosed with cervical lesions graded as CIN2 or higher (CIN2+) during routine screening. The Veneto Regional Health Service developed a 22-item questionnaire to measure the gap between ideal procedure and real practice regarding the offer of vaccination against HPV for women undergoing routine cervical screening. The questionnaire was administered to nine expert doctors, one at each of the region's Local Health Units (LHUs). An additional specific assessment concerned the quality of the related web pages available on the LHU websites. Strategies to close the gap between ideal procedure and real practice were decided collegially, and a checklist to support good practices was developed and shared with operators at the LHUs. Changes in practice were measured using data relating to women diagnosed with CIN2+ lesions extracted from the regional oncological screening database before and after the publication of a Regional Procedure on the topic. The LHUs differed considerably in how they managed each step, in terms of training for healthcare personnel, organization and assessment of the pathway from cervical screening to HPV vaccination, and in dedicated website communication. After implementing the quality improvement strategy, the proportion of women given a first dose of HPV vaccine within 3 months of being diagnosed with CIN2+ lesions at 1st-level screening rose to 50% (compared with 30.85% beforehand), and the median time elapsing between a diagnosis of CIN2+ lesion and a first dose of HPV vaccine dropped from 158 to 90 days. These findings underscore the importance of providing training to promote vaccination for general practitioners and other clinicians. The study also confirms the need for more efforts in communication to ensure that any citizen has the opportunity to access preventive healthcare.

4.
Thorac Cancer ; 13(19): 2692-2698, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35971638

RESUMEN

BACKGROUND: The monoclonal antibody durvalumab, an immune-checkpoint inhibitor (ICI) antiprogrammed death ligand 1 (PD-L1), is available for unresectable stage III NSCLC patients as consolidation therapy following induction chemoradiotherapy, with very promising overall survival (OS) and progression-free survial (PFS) results in registration trials. The purpose of this study was to provide policymakers with an estimate of the cost-effectiveness of durvalumab in the treatment of non-small cell lung cancer (NSCLC). METHODS: The study developed a Markov model covering a 5-year period to compare costs and outcomes of treating PD-L1 positive patients with or without durvalumab. We conducted a series of sensitivity analyses (Tornado analysis and Monte Carlo simulation) by varying some parameters to assess the robustness of our model and identify the parameters with the greatest impact on cost-effectiveness. RESULTS: Prior to the release of durvalumab, the management of NSCLC over a 5-year period cost €33 317 per patient, with an average life expectancy of 2.01 years. After the introduction of the drug, this increased to €37 317 per patient, with an average life expectancy of 2.13 years. Treatment with durvalumab led to an incremental cost-effectiveness ratio (ICER) of €35 526 per year. OS is the variable that contributes the most to the variability of the ICER. CONCLUSIONS: The study observed that durvalumab is a cost-effective treatment option for patients with unresectable stage III NSCLC.


Asunto(s)
Antineoplásicos Inmunológicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos Inmunológicos/efectos adversos , Antígeno B7-H1/uso terapéutico , Quimioradioterapia/efectos adversos , Análisis Costo-Beneficio , Humanos , Inhibidores de Puntos de Control Inmunológico
5.
Nat Commun ; 13(1): 2559, 2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35562350

RESUMEN

c-MYC (MYC) is a major driver of prostate cancer tumorigenesis and progression. Although MYC is overexpressed in both early and metastatic disease and associated with poor survival, its impact on prostate transcriptional reprogramming remains elusive. We demonstrate that MYC overexpression significantly diminishes the androgen receptor (AR) transcriptional program (the set of genes directly targeted by the AR protein) in luminal prostate cells without altering AR expression. Analyses of clinical specimens reveal that concurrent low AR and high MYC transcriptional programs accelerate prostate cancer progression toward a metastatic, castration-resistant disease. Data integration of single-cell transcriptomics together with ChIP-seq uncover an increase in RNA polymerase II (Pol II) promoter-proximal pausing at AR-dependent genes following MYC overexpression without an accompanying deactivation of AR-bound enhancers. Altogether, our findings suggest that MYC overexpression antagonizes the canonical AR transcriptional program and contributes to prostate tumor initiation and progression by disrupting transcriptional pause release at AR-regulated genes.


Asunto(s)
Neoplasias de la Próstata , Receptores Androgénicos , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Regulación Neoplásica de la Expresión Génica , Genes myc , Humanos , Masculino , Próstata/patología , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-myc , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo
6.
Vaccines (Basel) ; 9(8)2021 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-34451990

RESUMEN

Vaccination against SARS-CoV-2 will likely be the most promising way to combat the pandemic. Even if mass vaccination is urgent, it should still always be supported by appropriate patient safety management. The aim of this study, based on failure mode, effects and criticality analysis (FMECA), was to identify possible failures and highlight measures that can be adopted to prevent their occurrence. A team of resident doctors in public health from the University of Padua and specialists in risk analysis in public health examined the mass vaccination process. A diagram was drafted to illustrate the various phases of mass vaccination, analyze the process, and identify all failure modes. Criticalities were ascertained by rating the severity, frequency and likelihood of failure detection on a scale of 1 to 10. We identified a total of 71 possible faults distributed over the various phases of the process, and 34 of them were classified as carrying a high risk. For the potentially high-risk failure modes, we identified 63 recommended actions to contain the cause of their occurrence or improve their detection. For the purpose of detecting potential failures, FMECA can be successfully applied to mass vaccination, which should be considered a high-risk process.

7.
JCO Oncol Pract ; 17(8): e1085-e1093, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33826354

RESUMEN

PURPOSE: The present work aimed at conducting a real-world data analysis on the management costs and survival analysis comparing data from non-small-cell lung cancer (NSCLC) cases diagnosed in the Veneto region before (2015) and after (2017) the implementation of a regional diagnostic and therapeutic pathway including all new diagnostic and therapeutic strategies. METHOD: This study considered 254 incidental cases of NSCLC in 2015 and 228 in 2017 within the territory of the Padua province (Italy), as recorded by the Veneto Cancer Registry. Tobit regression analysis was performed to verify if total and each item costs (2 years after NSCLC diagnosis) are associated with index year, adjusting by year of diagnosis, sex, age, and stage at diagnosis. Logistic regression models were run to study overall mortality at 2 years, adjusting by the same covariates. RESULTS: The 2017 cohort had a lower mortality odd (odds ratio, 0.93; P = .02) and a significant increase in the average overall costs (P = .009) than the 2015 cohort. The Tobit regression analysis by cost item showed a very significant increase in the average cost of drugs (coefficient = 5,953, P = .008) for the 2017 cohort, as well as a decrease in the average cost of hospice care (coefficient = -1,822.6, P = .022). CONCLUSION: Our study showed a survival improvement for patients with NSCLC as well as an economic burden growth. Physicians should therefore be encouraged to follow new clinical care pathways, while the steadily rising related costs underscore the need for policymakers and health professionals to pursue.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Estudios de Cohortes , Costos de la Atención en Salud , Humanos , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/terapia , Análisis de Supervivencia
8.
Cancer Prev Res (Phila) ; 14(4): 403-414, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33509805

RESUMEN

Despite several epidemiologic and preclinical studies supporting the role of diet in cancer progression, the complexity of the diet-cancer link makes it challenging to deconvolute the underlying mechanisms, which remain scantly elucidated. This review focuses on genomic instability as one of the cancer hallmarks affected by diet-dependent metabolic alterations. We discuss how altered dietary intake of metabolites of the one-carbon metabolism, including methionine, folate, and vitamins B and C, can impact the methylation processes and thereby tumorigenesis. We present the concept that the protumorigenic effect of certain diets, such as the Western diet, is in part due to a diet-induced erosion of the DNA repair capacity caused by altered epigenetic and epitranscriptomic landscapes, while the protective effect of other dietary patterns, such as the Mediterranean diet, can be partly explained by their ability to sustain a proficient DNA repair. In particular, considering that diet-dependent alterations of the one-carbon metabolism can impact the rate of methylation processes, changes in dietary patterns can affect the activity of writers and erasers of histone and RNA methyl marks and consequently impair their role in ensuring a proficient DNA damage repair.


Asunto(s)
Daño del ADN , Metilación de ADN , Reparación del ADN , Dieta , Inestabilidad Genómica , Neoplasias/patología , Animales , Humanos , Neoplasias/etiología , Neoplasias/metabolismo
9.
Thorac Cancer ; 12(1): 13-20, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33219738

RESUMEN

BACKGROUND: Non-small cell lung cancer (NSCLC) is the first cause of cancer-related death among men and the second among women worldwide. It also poses an economic threat to the sustainability of healthcare services. This study estimated the direct costs of care for patients with NSCLC by stage at diagnosis, and management phase of pathway recommended in local and international guidelines. METHODS: Based on the most up-to-date guidelines, we developed a very detailed "whole-disease" model listing the probabilities of all potentially necessary diagnostic and therapeutic actions involved in the management of each stage of NSCLC. We assigned a cost to each procedure, and obtained an estimate of the total and average per-patient costs of each stage of the disease and phase of its management. RESULTS: The mean expected cost of a patient with NSCLC is 21,328 € (95% C.I. -20 897-22 322). This cost is 16 291 € in stage I, 19530 € in stage II, 21938 € in stage III, 22175 € in stage IV, and 28 711 € for a Pancoast tumor. In the early stages of the disease, the main cost is incurred by surgery, whereas in the more advanced stages radiotherapy, medical therapy, treatment for progressions, and supportive care become variously more important. CONCLUSIONS: An estimation of the direct costs of care for NSCLC is fundamental in order to predict the burden of new oncological therapies and treatments on healthcare services, and thus orient the decisions of policy-makers regarding the allocation of resources. KEY POINTS: SIGNIFICANT FINDINGS OF THE STUDY: The high costs of surgery make the early stages of the disease no less expensive than the advanced stages. WHAT THIS STUDY ADDS: An estimation of the direct costs of care is fundamental in order to orient the decisions of policy-makers regarding the allocation of resources.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/economía , Neoplasias Pulmonares/economía , Manejo de la Enfermedad , Femenino , Humanos , Masculino , Estadificación de Neoplasias
11.
Artículo en Inglés | MEDLINE | ID: mdl-32397210

RESUMEN

In Italy, wine production is considered a sector of excellence, where the wines' appreciable sensory features are favored by environmental factors, including weather and climate conditions, which benefit territories with a specific vocation. The whole chain involves many economic and agri-food sector operators, and requires an in-depth assessment of specific risks for identifying critical points, keeping the entire production process under control, and ensuring product traceability. This article describes the results of a pilot study conducted in the Prosecco DOCG (Designations of Controlled and Guaranteed Origin) area, concerning the detection of residues of plant protection products in fifty wine bottles. Although considerably below the maximum residue levels, all the samples tested were positive, ranging from two to five active substances detected in each sample. In addition to the provisions of the European Community legislation, this paper critically evaluates some best practices models that are already used by the Wine Federations of Italy, with the aim of identifying advantages of and areas for improvement in production methods, applicable to raw materials reception, rasping, storage, and bottling phases, in order to guarantee product safety and quality.


Asunto(s)
Industria de Alimentos/normas , Inocuidad de los Alimentos , Vino , Italia , Proyectos Piloto , Tiempo (Meteorología) , Vino/análisis
12.
Eur J Surg Oncol ; 46(6): 976-981, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32146052

RESUMEN

BACKGROUND: Clinical factors, such as tumor thickness, ulceration and growth phase have a role as prognostic factors for stage I melanoma. However, it is still under debate whether these variables influence the related direct costs. We aimed to investigate which clinical factors represent direct health care "cost drivers" for stage I melanoma. MATERIALS AND METHOD: Analyses were conducted on a cohort of patients diagnosed with stage I melanoma. Differences in the costs incurred by different groups of patients were examined using Mann-Whitney or Kruskal-Wallis non-parametric tests. Log linear multivariate analysis was used to identify the clinical drivers of the total direct costs one and two years after diagnosis. The study was conducted from the perspective of Italy's National Health care System. RESULTS: One year after diagnosis, patients whose melanomas had a Breslow thickness ≥0.8 mmin (compared with those with lower thickness) and a vertical growth phase (compared with those with radial growth) incurred higher costs for hospitalization, as well as higher overall costs. One year after their diagnosis, treatment of patients with stage I melanoma in the vertical growth phase costs 50% more (95% CI: 22-85%) than their counterparts with a radial growth pattern, resulting in an estimated absolute increase of € 256.23. Having a tumor thicker than 0.8 mm prompted an increase of 91% (95% CI: 43-155%) in the costs (€955.24 in absolute terms). CONCLUSION: Our data indicate a heterogeneity in the direct costs of stage I melanoma patients during the first year after diagnosis, which can be partly explained by clinical prognostic factors, like tumor thickness and growth pattern.


Asunto(s)
Costos de la Atención en Salud , Melanoma/economía , Estadificación de Neoplasias/economía , Neoplasias Cutáneas/economía , Humanos , Melanoma/diagnóstico , Pronóstico , Neoplasias Cutáneas/diagnóstico , Melanoma Cutáneo Maligno
13.
BMC Public Health ; 20(1): 53, 2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-31937272

RESUMEN

BACKGROUND: Pulmonary diseases are a common and costly cause of 30-day readmissions. Few studies have focused on the difference in risk for rehospitalization between men and women in older patients. In this study we analyzed the association between sex and the risk of readmission in a cohort of patients admitted to the hospital for chronic obstructive pulmonary disease (COPD) exacerbation and other major pulmonary diseases. METHODS: This was a retrospective cohort study based on administrative data collected in the Veneto Region in 2016. We included 14,869 hospital admissions among residents aged ≥65 years for diagnosis related groups (DRGs) of the most common disorders of the respiratory system: bronchitis and asthma, pneumonia, pulmonary edema, respiratory failure, and COPD. Multilevel logistic regressions were performed to test the association between 30-day hospital readmission and sex, adjusting for confounding factors. RESULTS: For bronchitis and asthma, male patients had significantly higher odds of 30-day readmission than female patients (adjusted odds ratio (aOR), 2.07; 95% confidence interval (CI), 1.11-3.87). The odds of readmission for men were also significantly higher for pneumonia (aOR, 1.40; 95% CI, 1.13-1.72), for pulmonary edema and respiratory failure (aOR, 1.28; 95% CI, 1.05-1.55), and for COPD (aOR, 1.34; 95% CI, 1.00-1.81). CONCLUSIONS: This study found that male sex is a major risk factors for readmission in patients aged more than 65 years with a primary pulmonary diagnosis. More studies are needed to understand the underlying determinants of this phenomena and to provide targets for future interventions.


Asunto(s)
Enfermedades Pulmonares/terapia , Readmisión del Paciente/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales
14.
J Prev Med Hyg ; 61(4): E497-E500, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33628952

RESUMEN

In March 2020, the COVID-19 pandemic disrupted most of the routine outpatient activities in Italian hospitals and Prevention Departments, including those vaccinations which were not urgent and/or scheduled for children aged 0-6 years. Since June 2020, when the pandemic entered a milder phase, in the alpine Province of Belluno (Veneto, North-Eastern Italy), 12,152 doses of vaccine against tick-borne encephalitis have been administered by means of the innovative "drive-through" modality. No significant adverse events have occurred and popular demand has steadily grown, proving the "drive-through" approach to be safe, efficient and successful.


Asunto(s)
COVID-19/epidemiología , Encefalitis Transmitida por Garrapatas/prevención & control , Vacunación/estadística & datos numéricos , Vacunas Virales/administración & dosificación , Instituciones de Atención Ambulatoria/organización & administración , Niño , Protección a la Infancia/estadística & datos numéricos , Encefalitis Transmitida por Garrapatas/inmunología , Humanos , Italia
15.
Ig Sanita Pubbl ; 75(6): 451-460, 2019.
Artículo en Italiano | MEDLINE | ID: mdl-32242169

RESUMEN

Glyphosate is the best-selling herbicide in the world and in 2015 the International Agency for Research on Cancer listed it among the "probable carcinogens for humans", opening a scientific debate that is still going on. On these premises, in 2016, extraordinary samplings of glyphosate, its metabolite AMPA, and a similar compound, ammonium glufosinate, were carried out in 12 wells of the water network intended for domestic consumption in the territory of the Local Health Unit 2 - District of Pieve di Soligo, Province of Treviso, Veneto region, Italy. The area includes 13 municipalities at high-intensity "Prosecco d.o.c.g." wine production. Traces of glyphosate (maximum reached 0.08 µg/L) and AMPA (maximum reached 0.25 µg/L, beyond the legal limit of 0.1 µg/L for drinking water) were detected in 2 wells supplying an urban area. No samples contained traces of ammonium glufosinate. Following these findings, an inter-municipal order to suspend the use of glyphosate was introduced and then entered definitively in the rural police regulation concerning all the municipalities in the Prosecco d.o.c.g. area, which led to the elimination of glyphosate and AMPA also in the initially contaminated wells. The case shows that high-consumption herbicides can reach the drinking water network of a city surrounded by territories with high agricultural activity. Moreover, the combined intervention of the institutions was fundamental to eliminate a "probable carcinogen" from the urban drinking water and to promote the abandonment of potentially harmful agricultural practices in favor of solutions with reduced environmental and health impact.


Asunto(s)
Monitoreo del Ambiente , Glicina/análogos & derivados , Contaminantes Químicos del Agua , Vino , Ciudades , Glicina/efectos adversos , Humanos , Italia , Glifosato
16.
Oncogene ; 37(16): 2150-2164, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29371679

RESUMEN

Although ΔNp63 is known to promote cancer cell proliferation, the underlying mechanism behind its oncogenic function remains elusive. We report here a functional interplay between ΔNp63 and Δ133p53. These two proteins are co-overexpressed in a subset of human cancers and cooperate to promote cell proliferation. Mechanistically, Δ133p53 binds to ΔNp63 and utilizes its transactivation domain to upregulate GLUT1, GLUT4, and PGM expression driving glycolysis. While increased glycolysis provides cancer cells with anabolic metabolism critical for proliferation and survival, it can be harnessed for selective cancer cell killing. Indeed, we show that tumors overexpressing both ΔNp63 and Δ133p53 exhibit heightened sensitivity to vitamin C that accumulate to a lethal level due to accelerated uptake via overexpressed GLUT1. These observations offer a new therapeutic avenue that could be exploited for clinical applications.


Asunto(s)
Proliferación Celular/genética , Glucólisis/genética , Neoplasias/patología , Factores de Transcripción/fisiología , Proteína p53 Supresora de Tumor/fisiología , Proteínas Supresoras de Tumor/fisiología , Células A549 , Animales , Metabolismo de los Hidratos de Carbono/genética , Células Cultivadas , Codón sin Sentido , Femenino , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Células MCF-7 , Ratones , Ratones Desnudos , Proteínas Mutantes/genética , Proteínas Mutantes/fisiología , Neoplasias/genética , Neoplasias/metabolismo , Isoformas de Proteínas/fisiología , Factores de Transcripción/genética , Proteína p53 Supresora de Tumor/genética , Proteínas Supresoras de Tumor/genética
17.
J Mol Cell Biol ; 9(2): 154-165, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-27927748

RESUMEN

Deregulation of the tyrosine kinase signalling is often associated with tumour progression and drug resistance, but its underlying mechanisms are only partly understood. In this study, we investigated the effects of the receptor tyrosine kinase AXL on the stability of the MDMX-MDM2 heterocomplex and the activity of p53 in melanoma cells. Our data demonstrated that AXL overexpression or activation through growth arrest-specific 6 (Gas6) ligand stimulation increases MDMX and MDM2 protein levels and decreases p53 activity. Upon activation, AXL stabilizes MDMX through a post-translational modification that involves phosphorylation of MDMX on the phosphosite Ser314, leading to increased affinity between MDMX and MDM2 and favouring MDMX nuclear translocation. Ser314 phosphorylation can also protect MDMX from MDM2-mediated degradation, leading to stabilization of the MDMX-MDM2 complex. We identified CDK4/6 and p38 MAPK as the two kinases mediating AXL-induced modulation of the MDMX-MDM2 complex, and demonstrated that suppression of AXL, either through siRNA silencing or pharmacological inhibition, increases expression levels of p53 target genes P21, MDM2, and PUMA, improves p53 pathway response to chemotherapy, and sensitizes cells to both Cisplatin and Vemurafenib. Our findings offer an insight into a novel signalling axis linking AXL to p53 and provide a potentially druggable pathway to restore p53 function in melanoma.


Asunto(s)
Melanoma/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal , Proteína p53 Supresora de Tumor/metabolismo , Proteínas de Ciclo Celular , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Cisplatino/farmacología , Quinasas Ciclina-Dependientes/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Humanos , Indoles/farmacología , Melanoma/patología , Fosforilación/efectos de los fármacos , Fosfoserina/metabolismo , Estabilidad Proteica/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Proteolisis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Sulfonamidas/farmacología , Transcripción Genética/efectos de los fármacos , Proteína p53 Supresora de Tumor/genética , Vemurafenib , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Tirosina Quinasa del Receptor Axl
18.
J Biol Chem ; 291(50): 25937-25949, 2016 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-27777309

RESUMEN

Deregulated receptor tyrosine kinase (RTK) signaling is frequently associated with tumorigenesis and therapy resistance, but its underlying mechanisms still need to be elucidated. In this study, we have shown that the RTK human epidermal growth factor receptor 4 (Her4, also known as Erbb4) can inhibit the tumor suppressor p53 by regulating MDMX-mouse double minute 2 homolog (MDM2) complex stability. Upon activation by either overexpression of a constitutively active vector or ligand binding (Neuregulin-1), Her4 was able to stabilize the MDMX-MDM2 complex, resulting in suppression of p53 transcriptional activity, as shown by p53-responsive element-driven luciferase assay and mRNA levels of p53 target genes. Using a phospho-proteomics approach, we functionally identified a novel Her4-induced posttranslational modification on MDMX at Ser-314, a putative phosphorylation site for the CDK4/6 kinase. Remarkably, inhibition of Ser-314 phosphorylation either with Ser-to-Ala substitution or with a specific inhibitor of CDK4/6 kinase blocked Her4-induced stabilization of MDMX-MDM2 and rescued p53 activity. Our study offers insights into the mechanisms of deregulated RTK-induced carcinogenesis and provides the basis for the use of inhibitors targeting RTK-mediated signals for p53 restoration.


Asunto(s)
Proteínas Nucleares/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Receptor ErbB-4/metabolismo , Transcripción Genética , Proteína p53 Supresora de Tumor/metabolismo , Animales , Proteínas de Ciclo Celular , Quinasa 4 Dependiente de la Ciclina/genética , Quinasa 4 Dependiente de la Ciclina/metabolismo , Quinasa 6 Dependiente de la Ciclina/genética , Quinasa 6 Dependiente de la Ciclina/metabolismo , Células HEK293 , Humanos , Células MCF-7 , Ratones , Fosforilación , Proteínas Proto-Oncogénicas c-mdm2/genética , Receptor ErbB-4/genética , Proteína p53 Supresora de Tumor/genética
19.
Transl Cancer Res ; 5(6): 725-732, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30319942

RESUMEN

The tumor suppressor p53 plays a central role in safeguarding cellular homeostasis. Upon various types of stress signals such as DNA damage or oncogenic stress, p53 is promptly activated to prevent and repair damages that can threaten the genome stability. The two major negative regulators of p53 are MDM2 and MDMX, two homolog proteins that control p53 activity and turnover, hence keeping it in check during normal cell cycling. In the event of cellular stress, they have to be inhibited in order to relieve p53 from their suppression and allow its activation. As the essential upstream modulator of p53, the MDMX-MDM2 complex integrates multiple signaling pathways regulating p53 response to perturbations of cellular homeostasis. Given its predominantly cytoplasmic localization in normal conditions, we hypothesize that MDMX, rather than MDM2, is the first recipient of signaling cues directed towards the MDMX-MDM2 complex and aimed at modulating p53. In this review we give a synthetic overview of the phosphorylation sites of MDMX that are known to affect its degradation, ubiquitination, intracellular localization and interaction with MDM2 and p53, ultimately modulating the stability and activity of p53. The role of MDMX in response to the main types of cellular stress is also briefly discussed, along with the potential of the MDMX-MDM2 complex as therapeutic target to restore p53 activity.

20.
PLoS One ; 9(10): e110467, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25338069

RESUMEN

Fish are an important model for the pharmacological and toxicological characterization of human pharmaceuticals in drug discovery, drug safety assessment and environmental toxicology. However, do fish respond to pharmaceuticals as humans do? To address this question, we provide a novel quantitative cross-species extrapolation approach (qCSE) based on the hypothesis that similar plasma concentrations of pharmaceuticals cause comparable target-mediated effects in both humans and fish at similar level of biological organization (Read-Across Hypothesis). To validate this hypothesis, the behavioural effects of the anti-depressant drug fluoxetine on the fish model fathead minnow (Pimephales promelas) were used as test case. Fish were exposed for 28 days to a range of measured water concentrations of fluoxetine (0.1, 1.0, 8.0, 16, 32, 64 µg/L) to produce plasma concentrations below, equal and above the range of Human Therapeutic Plasma Concentrations (H(T)PCs). Fluoxetine and its metabolite, norfluoxetine, were quantified in the plasma of individual fish and linked to behavioural anxiety-related endpoints. The minimum drug plasma concentrations that elicited anxiolytic responses in fish were above the upper value of the H(T)PC range, whereas no effects were observed at plasma concentrations below the H(T)PCs. In vivo metabolism of fluoxetine in humans and fish was similar, and displayed bi-phasic concentration-dependent kinetics driven by the auto-inhibitory dynamics and saturation of the enzymes that convert fluoxetine into norfluoxetine. The sensitivity of fish to fluoxetine was not so dissimilar from that of patients affected by general anxiety disorders. These results represent the first direct evidence of measured internal dose response effect of a pharmaceutical in fish, hence validating the Read-Across hypothesis applied to fluoxetine. Overall, this study demonstrates that the qCSE approach, anchored to internal drug concentrations, is a powerful tool to guide the assessment of the sensitivity of fish to pharmaceuticals, and strengthens the translational power of the cross-species extrapolation.


Asunto(s)
Antidepresivos de Segunda Generación/farmacocinética , Fluoxetina/análogos & derivados , Fluoxetina/farmacocinética , Animales , Antidepresivos de Segunda Generación/sangre , Antidepresivos de Segunda Generación/farmacología , Ansiedad/tratamiento farmacológico , Conducta Animal/efectos de los fármacos , Biotransformación , Cyprinidae , Relación Dosis-Respuesta a Droga , Fluoxetina/sangre , Fluoxetina/farmacología , Humanos , Masculino , Grabación en Video
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