106 research outputs found

    Alteraciones de los patrones de 5- hidroximetilcitosina en enzimas epigenéticas en glioma

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    La 5-hidroximetilcitosina (5hmC) es una marca epigenética de descubrimiento reciente que surge de la oxidación de la 5-metilcitosina (5mC) catalizada por los enzimas TETs. De entre todos los tejidos, es en el Sistema Nervioso Central (SNC) donde se encuentran los niveles más elevados. Así pues, los gliomas, un grupo heterogéneo de tumores del SNC, se presentan como un buen candidato para el estudio de variaciones en los niveles de 5hmC. Previamente en el grupo de investigación, se encontraron diferencias en los niveles de metilación e hidroximetilación en varios genes entre muestras de glioma de pacientes y cerebros no tumorales. De todos ellos, el gen candidato, que codifica a un enzima metiltransferasa, mostró disminuciones en los niveles de 5hmC acompañados de un incremento de 5mC en regiones intragénicas. Con el fin de averiguar la implicación del gen candidato en gliomas, en primer lugar, se comprobó la posible asociación entre los niveles de 5mC y 5hmC intragénica y la expresión del gen candidato a través de tratamientos con la droga epigenética 5-aza- 2´-deoxicitidina y vitamina C. El tratamiento con 5-aza-2´-deoxicitidina disminuye los niveles de 5mC, eleva los de 5hmC intragénica e incrementa la expresión génica del gen candidato en un 45%, mientras que el tratamiento combinado con vitamina C la incrementa en un 85%. A continuación, se caracterizaron clones con expresión ectópica del gen candidato en una línea celular de glioma. Nuestros resultados muestran que dicha sobreexpresión provoca una disminución en la proliferación y viabilidad celular, sugiriendo un posible papel supresor tumoral del gen

    Sirt1 protects from K-Ras-driven lung carcinogenesis.

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    The NAD+-dependent deacetylase SIRT1 can be oncogenic or tumor suppressive depending on the tissue. Little is known about the role of SIRT1 in non-small cell lung carcinoma (NSCLC), one of the deadliest cancers, that is frequently associated with mutated K-RAS Therefore, we investigated the effect of SIRT1 on K-RAS-driven lung carcinogenesis. We report that SIRT1 protein levels are downregulated by oncogenic K-RAS in a MEK and PI3K-dependent manner in mouse embryo fibroblasts (MEFs), and in human lung adenocarcinoma cell lines. Furthermore, Sirt1 overexpression in mice delays the appearance of K-RasG12V-driven lung adenocarcinomas, reducing the number and size of carcinomas at the time of death and extending survival. Consistently, lower levels of SIRT1 are associated with worse prognosis in human NSCLCs. Mechanistically, analysis of mouse Sirt1-Tg pneumocytes, isolated shortly after K-RasG12V activation, reveals that Sirt1 overexpression alters pathways involved in tumor development: proliferation, apoptosis, or extracellular matrix organization. Our work demonstrates a tumor suppressive role of SIRT1 in the development of K-RAS-driven lung adenocarcinomas in mice and humans, suggesting that the SIRT1-K-RAS axis could be a therapeutic target for NSCLCs.We thank Jesus Herranz for his biostatistical advice; and Alba de Martino, Patricia Gonzalez, Maria Gomez, and Zaira Vega, from the Histopathology Unit at the CNIO, for their work in mouse histopathology. Work in the laboratory of P.J.F.-M. was funded by the IMDEA Food, the Spanish Association against Cancer (aecc) and the Ramon Areces (CIVP18A3891) Foundation. Work in the laboratory of M.S. was funded by the CNIO and by grants from the Spanish Ministry of Economy co-funded by the European Regional Development Fund (SAF project), the European Research Council (ERC Advanced Grant), the European Union (RISK-IR project), and the Botin Foundation and Banco Santander (Santander Universities Global Division). Work in the laboratory of DH was funded by Rutgers Cancer Institute of New Jersey, the Alex's Lemonade Stand Foundation Shark Tank Award and by the National Institutes of Health Grant K99/R00 CA197869. Work in the laboratory of M.S.C. was supported by a grant (SAF2012-40026) from the Spanish Ministry of Science and Innovation. L.F.C-M. was supported by a PhD Fellowship from the Portuguese Foundation for Science and Technology (FCT-MCTES, SFRH/BD/124022/2016).S

    TIM-3 blockade in diffuse intrinsic pontine glioma models promotes tumor regression and antitumor immune memory

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    Diffuse intrinsic pontine glioma (DIPG) is an aggressive brain stem tumor and the leading cause of pediatric cancer-related death. To date, these tumors remain incurable, underscoring the need for efficacious therapies. In this study, we demonstrate that the immune checkpoint TIM-3 (HAVCR2) is highly expressed in both tumor cells and microenvironmental cells, mainly microglia and macrophages, in DIPG. We show that inhibition of TIM-3 in syngeneic models of DIPG prolongs survival and produces long-term survivors free of disease that harbor immune memory. This antitumor effect is driven by the direct effect of TIM-3 inhibition in tumor cells, the coordinated action of several immune cell populations, and the secretion of chemokines/cytokines that create a proinflammatory tumor microenvironment favoring a potent antitumor immune response. This work uncovers TIM-3 as a bona fide target in DIPG and supports its clinical translation

    Epigenetic deregulation of the histone methyltransferase KMT5B contributes to malignant transformation in glioblastoma

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    Glioblastoma multiforme (GBM) is the most common and aggressive type of brain tumor in adulthood. Epigenetic mechanisms are known to play a key role in GBM although the involvement of histone methyltransferase KMT5B and its mark H4K20me2 has remained largely unexplored. The present study shows that DNA hypermethylation and loss of DNA hydroxymethylation is associated with KMT5B downregulation and genome-wide reduction of H4K20me2 levels in a set of human GBM samples and cell lines as compared with non-tumoral specimens. Ectopic overexpression of KMT5B induced tumor suppressor-like features in vitro and in a mouse tumor xenograft model, as well as changes in the expression of several glioblastoma-related genes. H4K20me2 enrichment was found immediately upstream of the promoter regions of a subset of deregulated genes, thus suggesting a possible role for KMT5B in GBM through the epigenetic modulation of key target cancer genes.This research was funded by the Health Institute Carlos III (Plan Nacional de I+D+I) cofounding FEDER (PI15/00892 and PI18/01527 to MF and AF); the Government of the Principality of Asturias PCTI-Plan de Ciencia, Tecnología e Innovación de Asturias co-funding 2018–2022/FEDER (IDI/2018/146 to MF); AECC (PROYE18061FERN to MF); FGCSIC (0348_CIE_6_E to MF); Severo Ochoa Program BP17-165 to PS-O and BP17-114 to RP); the Ministry of Economy and Competitiveness of Spain (VL, Juan de la Cierva fellowship IJCI-2015-23316; JT, Juan de la Cierva fellowship FJCI-2015-26965); FICYT (AC and MG); FINBA-ISPA (VL); and IUOPA (VL and CM). The IUOPA is supported by the Obra Social Cajastur-Liberbank, Spain.Peer reviewe

    The Oncolytic Adenovirus Delta-24-RGD in Combination With ONC201 Induces a Potent Antitumor Response in Pediatric High-Grade and Diffuse Midline Glioma Models

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    BACKGROUND: Pediatric high-grade gliomas (pHGGs), including diffuse midline gliomas (DMGs), are aggressive pediatric tumors with one of the poorest prognoses. Delta-24-RGD and ONC201 have shown promising efficacy as single agents for these tumors. However, the combination of both agents has not been evaluated. METHODS: The production of functional viruses was assessed by immunoblotting and replication assays. The antitumor effect was evaluated in a panel of human and murine pHGG and DMG cell lines. RNAseq, the seahorse stress test, mitochondrial DNA content, and γH2A.X immunofluorescence were used to perform mechanistic studies. Mouse models of both diseases were used to assess the efficacy of the combination in vivo. The tumor immune microenvironment was evaluated using flow cytometry, RNAseq, and multiplexed immunofluorescence staining. RESULTS: The Delta-24-RGD/ONC201 combination did not affect the virus replication capability in human pHGG and DMG models in vitro. Cytotoxicity analysis showed that the combination treatment was either synergistic or additive. Mechanistically, the combination treatment increased nuclear DNA damage and maintained the metabolic perturbation and mitochondrial damage caused by each agent alone. Delta-24-RGD/ONC201 cotreatment extended the overall survival of mice implanted with human and murine pHGG and DMG cells, independent of H3 mutation status and location. Finally, combination treatment in murine DMG models revealed a reshaping of the tumor microenvironment to a proinflammatory phenotype. CONCLUSIONS: The Delta-24-RGD/ONC201 combination improved the efficacy compared to each agent alone in in vitro and in vivo models by potentiating nuclear DNA damage and in turn improving the antitumor (immune) response to each agent alone

    Safety and immunogenicity of the protein-based PHH-1V compared to BNT162b2 as a heterologous SARS-CoV-2 booster vaccine in adults vaccinated against COVID-19 : a multicentre, randomised, double-blind, non-inferiority phase IIb trial

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    A SARS-CoV-2 protein-based heterodimer vaccine, PHH-1V, has been shown to be safe and well-tolerated in healthy young adults in a first-in-human, Phase I/IIa study dose-escalation trial. Here, we report the interim results of the Phase IIb HH-2, where the immunogenicity and safety of a heterologous booster with PHH-1V is assessed versus a homologous booster with BNT162b2 at 14, 28 and 98 days after vaccine administration. The HH-2 study is an ongoing multicentre, randomised, active-controlled, double-blind, non-inferiority Phase IIb trial, where participants 18 years or older who had received two doses of BNT162b2 were randomly assigned in a 2:1 ratio to receive a booster dose of vaccine-either heterologous (PHH-1V group) or homologous (BNT162b2 group)-in 10 centres in Spain. Eligible subjects were allocated to treatment stratified by age group (18-64 versus ≥65 years) with approximately 10% of the sample enrolled in the older age group. The primary endpoints were humoral immunogenicity measured by changes in levels of neutralizing antibodies (PBNA) against the ancestral Wuhan-Hu-1 strain after the PHH-1V or the BNT162b2 boost, and the safety and tolerability of PHH-1V as a boost. The secondary endpoints were to compare changes in levels of neutralizing antibodies against different variants of SARS-CoV-2 and the T-cell responses towards the SARS-CoV-2 spike glycoprotein peptides. The exploratory endpoint was to assess the number of subjects with SARS-CoV-2 infections ≥14 days after PHH-1V booster. This study is ongoing and is registered with , . From 15 November 2021, 782 adults were randomly assigned to PHH-1V (n = 522) or BNT162b2 (n = 260) boost vaccine groups. The geometric mean titre (GMT) ratio of neutralizing antibodies on days 14, 28 and 98, shown as BNT162b2 active control versus PHH-1V, was, respectively, 1.68 (p < 0.0001), 1.31 (p = 0.0007) and 0.86 (p = 0.40) for the ancestral Wuhan-Hu-1 strain; 0.62 (p < 0.0001), 0.65 (p < 0.0001) and 0.56 (p = 0.003) for the Beta variant; 1.01 (p = 0.92), 0.88 (p = 0.11) and 0.52 (p = 0.0003) for the Delta variant; and 0.59 (p ≤ 0.0001), 0.66 (p < 0.0001) and 0.57 (p = 0.0028) for the Omicron BA.1 variant. Additionally, PHH-1V as a booster dose induced a significant increase of CD4 + and CD8 + T-cells expressing IFN-γ on day 14. There were 458 participants who experienced at least one adverse event (89.3%) in the PHH-1V and 238 (94.4%) in the BNT162b2 group. The most frequent adverse events were injection site pain (79.7% and 89.3%), fatigue (27.5% and 42.1%) and headache (31.2 and 40.1%) for the PHH-1V and the BNT162b2 groups, respectively. A total of 52 COVID-19 cases occurred from day 14 post-vaccination (10.14%) for the PHH-1V group and 30 (11.90%) for the BNT162b2 group (p = 0.45), and none of the subjects developed severe COVID-19. Our interim results from the Phase IIb HH-2 trial show that PHH-1V as a heterologous booster vaccine, when compared to BNT162b2, although it does not reach a non-inferior neutralizing antibody response against the Wuhan-Hu-1 strain at days 14 and 28 after vaccination, it does so at day 98. PHH-1V as a heterologous booster elicits a superior neutralizing antibody response against the previous circulating Beta and the currently circulating Omicron BA.1 SARS-CoV-2 variants in all time points assessed, and for the Delta variant on day 98 as well. Moreover, the PHH-1V boost also induces a strong and balanced T-cell response. Concerning the safety profile, subjects in the PHH-1V group report significantly fewer adverse events than those in the BNT162b2 group, most of mild intensity, and both vaccine groups present comparable COVID-19 breakthrough cases, none of them severe. HIPRA SCIENTIFIC, S.L.U

    Una perspectiva multidisciplinaria

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    Derivado de la necesidad de fomentar la investigación multidisciplinaria, la Facultad de Economía de la Universidad Autónoma del Estado de México llevó a cabo los días 8 y 9 de septiembre de 2016, el VIII Coloquio de Investigación intitulado “Desarrollo económico, regional y sustentable”. En este magno evento se presentaron 36 ponencias agrupadas en cinco mesas de trabajo: sectores productivos, crecimiento económico y mercado de trabajo; tecnología, innovación y organizaciones; desigualdad regional, pobreza y migración; economía financiera e internacional; y medio ambiente y sociedad. Del material expuesto en el VIII Coloquio, se eligieron 16 investigaciones, mismas que integran este libro. Los estudios presentados en cada uno de los subsiguientes capítulos fueron seleccionados de acuerdo a un proceso de rigurosidad científica, siendo sometidos a dictamen por pares ciegos a partir de la integración de un Comité Académico de expertos. Lo anterior con la finalidad de proporcionar al lector un material de investigación de calidad y solidez científica respecto a temas de trascendencia vinculados con los sectores productivos, la innovación, las organizaciones, la responsabilidad social, la desigualdad, la educación y el medioambiente.Consecuencia de la apertura de los mercados y los preceptos competitivos dictados por la globalización, se manifiesta la necesidad de vincular los diversos saberes provenientes de las ciencias naturales y sociales, con el fin de complementar el conocimiento y generar nuevas formas de visualizar el entorno. A raíz de ello, la investigación multidisciplinaria asume un papel cada vez más importante en los círculos académicos, empresariales y gubernamentales. En este marco, entra en desuso la visualización del individuo como un sujeto atomístico desvinculado del medio ambiente que le rodea. El objetivo de este libro es otorgar una visión multidisciplinaria al estudio de temas económicos incorporando visiones teóricas y empíricas procedentes de las ciencias sociales y naturales. La obra está compuesta por 16 capítulos agrupados en cuatro secciones. La primera parte, conglomera cinco capítulos en torno a los tópicos sectores productivos y crecimiento económico.Facultad de Economía. Universidad Autónoma del Estado de Méxic

    Southern African Large Telescope Spectroscopy of BL Lacs for the CTA project

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    In the last two decades, very-high-energy gamma-ray astronomy has reached maturity: over 200 sources have been detected, both Galactic and extragalactic, by ground-based experiments. At present, Active Galactic Nuclei (AGN) make up about 40% of the more than 200 sources detected at very high energies with ground-based telescopes, the majority of which are blazars, i.e. their jets are closely aligned with the line of sight to Earth and three quarters of which are classified as high-frequency peaked BL Lac objects. One challenge to studies of the cosmological evolution of BL Lacs is the difficulty of obtaining redshifts from their nearly featureless, continuum-dominated spectra. It is expected that a significant fraction of the AGN to be detected with the future Cherenkov Telescope Array (CTA) observatory will have no spectroscopic redshifts, compromising the reliability of BL Lac population studies, particularly of their cosmic evolution. We started an effort in 2019 to measure the redshifts of a large fraction of the AGN that are likely to be detected with CTA, using the Southern African Large Telescope (SALT). In this contribution, we present two results from an on-going SALT program focused on the determination of BL Lac object redshifts that will be relevant for the CTA observatory

    Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

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    : The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity &gt; 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI
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