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

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.

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

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

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

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine

[This corrects the article DOI: 10.1186/s13054-016-1208-6.]

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

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

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.Peer reviewe

CD137 and PD-L1 targeting with immunovirotherapy induces a potent and durable antitumor immune response in glioblastoma models

Background Glioblastoma (GBM) is a devastating primary brain tumor with a highly immunosuppressive tumor microenvironment, and treatment with oncolytic viruses (OVs) has emerged as a promising strategy for these tumors. Our group constructed a new OV named Delta-24-ACT, which was based on the Delta-24-RGD platform armed with 4-1BB ligand (4-1BBL). In this study, we evaluated the antitumor effect of Delta-24-ACT alone or in combination with an immune checkpoint inhibitor (ICI) in preclinical models of glioma. Methods The in vitro effect of Delta-24-ACT was characterized through analyses of its infectivity, replication and cytotoxicity by flow cytometry, immunofluorescence (IF) and MTS assays, respectively. The antitumor effect and therapeutic mechanism were evaluated in vivo using several immunocompetent murine glioma models. The tumor microenvironment was studied by flow cytometry, immunohistochemistry and IF. Results Delta-24-ACT was able to infect and exert a cytotoxic effect on murine and human glioma cell lines. Moreover, Delta-24-ACT expressed functional 4-1BBL that was able to costimulate T lymphocytes in vitro and in vivo. Delta-24-ACT elicited a more potent antitumor effect in GBM murine models than Delta-24-RGD, as demonstrated by significant increases in median survival and the percentage of long-term survivors. Furthermore, Delta-24-ACT modulated the tumor microenvironment, which led to lymphocyte infiltration and alteration of their immune phenotype, as ..

CD137 and PD-L1 targeting with immunovirotherapy induces a potent and durable antitumor immune response in glioblastoma models

Background Glioblastoma (GBM) is a devastating primary brain tumor with a highly immunosuppressive tumor microenvironment, and treatment with oncolytic viruses (OVs) has emerged as a promising strategy for these tumors. Our group constructed a new OV named Delta-24-ACT, which was based on the Delta-24-RGD platform armed with 4-1BB ligand (4-1BBL). In this study, we evaluated the antitumor effect of Delta-24-ACT alone or in combination with an immune checkpoint inhibitor (ICI) in preclinical models of glioma. Methods The in vitro effect of Delta-24-ACT was characterized through analyses of its infectivity, replication and cytotoxicity by flow cytometry, immunofluorescence (IF) and MTS assays, respectively. The antitumor effect and therapeutic mechanism were evaluated in vivo using several immunocompetent murine glioma models. The tumor microenvironment was studied by flow cytometry, immunohistochemistry and IF. Results Delta-24-ACT was able to infect and exert a cytotoxic effect on murine and human glioma cell lines. Moreover, Delta-24-ACT expressed functional 4-1BBL that was able to costimulate T lymphocytes in vitro and in vivo. Delta-24-ACT elicited a more potent antitumor effect in GBM murine models than Delta-24-RGD, as demonstrated by significant increases in median survival and the percentage of long-term survivors. Furthermore, Delta-24-ACT modulated the tumor microenvironment, which led to lymphocyte infiltration and alteration of their immune phenotype, as ..