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1.
iScience ; 26(7): 106998, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37534176

RESUMEN

The tardigrade-unique damage suppressor protein (Dsup) can protect DNA from ionizing radiation and reactive oxygen species (ROS). In this study, we generated Dsup-expressing lines of Drosophila melanogaster and demonstrated that Dsup increased the survival rate after γ-ray irradiation and hydrogen peroxide treatment in flies too, but reduced the level of their locomotor activity. The transcriptome analyses of Dsup-expressing lines revealed a significant number of DEGs, >99% of which were down-regulated. Moreover, Dsup could bind RNA. These findings suggest that Dsup can act not only as a DNA protector but also as a non-specific transcriptional repressor and RNA-binding protein, that may lead to disturbance of a number of biological processes in D. melanogaster. The obtained data demonstrate features of the Dsup protein action in non-tardigrade organisms and can be used to understand the impact of other unspecific DNA/RNA-binding proteins on ROS and radiation resistance, gene expression, and epigenetic processes.

2.
Nat Commun ; 14(1): 341, 2023 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-36670096

RESUMEN

The transcriptional response to genotoxic stress involves gene expression arrest, followed by recovery of mRNA synthesis (RRS) after DNA repair. We find that the lack of the EXD2 nuclease impairs RRS and decreases cell survival after UV irradiation, without affecting DNA repair. Overexpression of wild-type, but not nuclease-dead EXD2, restores RRS and cell survival. We observe that UV irradiation triggers the relocation of EXD2 from mitochondria to the nucleus. There, EXD2 is recruited to chromatin where it transiently interacts with RNA Polymerase II (RNAPII) to promote the degradation of nascent mRNAs synthesized at the time of genotoxic attack. Reconstitution of the EXD2-RNAPII partnership on a transcribed DNA template in vitro shows that EXD2 primarily interacts with an elongation-blocked RNAPII and efficiently digests mRNA. Overall, our data highlight a crucial step in the transcriptional response to genotoxic attack in which EXD2 interacts with elongation-stalled RNAPII on chromatin to potentially degrade the associated nascent mRNA, allowing transcription restart after DNA repair.


Asunto(s)
Daño del ADN , Reparación del ADN , Cromatina/genética , Transcripción Genética , ARN Polimerasa II/genética , ARN Polimerasa II/metabolismo , ARN Mensajero/genética
3.
Biodivers Data J ; 10: e76100, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35095297

RESUMEN

BACKGROUND: Ground beetles (Carabidae, Coleoptera) are one of the most species-rich and well-studied insect families. However, the number of published datasets is disproportionately low against the biodiversity of this group. According to GBIF, only a fifth of the percentage of all published data covers ground beetles. This article describes a sampling-event dataset providing primary data on ground beetles collected in urban and suburban habitats in Kaluga, a typical central Russian city. We surveyed habitats of different land-use types and the extent and intensity of anthropogenic influence: yards, gardens, quarries, small urban woodlands, grasslands and riparian habitats. Carabids were collected by pitfall traps during most of the vegetative season (mostly from late April - early May to at least early October) for 13 seasons between 1994 and 2015. In total, the dataset contains 189 carabid species and 79,091 specimens. The dataset provides information about species composition and abundance, habitat distribution, seasonal and long-term dynamics of carabid beetles in environments of different degrees of urbanisation. NEW INFORMATION: This dataset is the first sampling-event dataset about carabids in various urban habitats published through GBIF.

4.
Biodivers Data J ; 9: e69807, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34759729

RESUMEN

BACKGROUND: Protected areas are organised in different climatic zones, which usually include typical ecosystems characteristic of certain climatic zones. In most cases, protected areas are biodiversity hotspots. These areas are benchmarks in terms of nature conservation and to determine their biological diversity is becoming an important task. It is important to investigate the carabid family of protected areas within the framework of understanding the overall biological diversity of these systems. In addition, ground beetles, as one of the largest groups of ground-based inhabitants, are indicators of the state of ecosystems and serve as markers of their well-being. NEW INFORMATION: We present 2,969 new occurrence records comprising 226 species of Carabidae, belonging to eight subfamilies, from the Mordovia State Nature Reserve (central Russia). Ten species are listed for the first time for the Mordovia State Nature Reserve fauna after previous research: Cicindelamaritima, Bembidionstriatum, Dyschiriusangustatus, Dyschiriusarenosus, Notiophilusaestuans, Bembidionargenteolum, Bembidionvelox, Bradycelluscaucasicus, Cymindisangularis and Syntomustruncatellus, five of which were first recorded for the Republic of Mordovia (Egorov et al. 2020). Previously, this information was not published anywhere and we wanted to make it available to everyone by embedding it in the global database on biodiversity (GBIF).

5.
Lancet Haematol ; 8(6): e410-e421, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34048680

RESUMEN

BACKGROUND: Despite advances in the treatment of Hodgkin lymphoma with the introduction of PET-adapted regimens, practical challenges prevent more widespread use of these approaches. The ECHELON-1 study assessed the safety and efficacy of front-line A+AVD (brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine) versus ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) in patients with stage III or IV classical Hodgkin lymphoma. The primary analysis showed improved modified progression-free survival with A+AVD. We present an updated analysis of ECHELON-1 at 5 years, an important landmark for this patient population. METHODS: ECHELON-1 was an international, open-label, randomised, phase 3 trial done at 218 clinical sites, including hospitals, cancer centres, and community clinics, in 21 countries. Previously untreated patients (≥18 years with an Eastern Cooperative Oncology Group performance status of ≤2) with stage III or IV classical Hodgkin lymphoma were randomly assigned (1:1) to receive A+AVD (brentuximab vedotin, 1·2 mg/kg of bodyweight, doxorubicin 25 mg/m2 of body surface area, vinblastine 6 mg/m2, and dacarbazine 375 mg/m2) or ABVD (doxorubicin 25 mg/m2, bleomycin 10 U/m2, vinblastine 6 mg/m2, and dacarbazine 375 mg/m2) intravenously on days 1 and 15 of each 28-day cycle for up to six cycles. Stratification factors included region (Americas vs Europe vs Asia) and International Prognostic Score risk group (low, intermediate, or high risk). The primary endpoint was modified progression-free survival; this 5-year update includes analysis of progression-free survival as per investigator assessment in the intention-to-treat population, which was an exploratory endpoint, although the 5-year analysis was not prespecified in the protocol. This trial is registered with ClinicalTrials.gov (NCT01712490) and EudraCT (2011-005450-60), and is ongoing. FINDINGS: Between Nov 19, 2012, and Jan 13, 2016, 1334 patients were randomly assigned to receive A+AVD (n=664) or ABVD (n=670). At a median follow-up of 60·9 months (IQR 52·2-67·3), 5-year progression-free survival was 82·2% (95% CI 79·0-85·0) with A+AVD and 75·3% (71·7-78·5) with ABVD (hazard ratio [HR] 0·68 [95% CI 0·53-0·87]; p=0·0017). Among PET-2-negative patients, 5-year progression-free survival was higher with A+AVD than with ABVD (84·9% [95% CI 81·7-87·6] vs 78·9% [75·2-82·1]; HR 0·66 [95% CI 0·50-0·88]; p=0·0035). 5-year progression-free survival for PET-2-positive patients was 60·6% (95% CI 45·0-73·1) with A+AVD versus 45·9% (32·7-58·2) with ABVD (HR 0·70 [95% CI 0·39-1·26]; p=0·23). Peripheral neuropathy continued to improve or resolve over time with both A+AVD (375 [85%] of 443 patients) and ABVD (245 [86%] of 286 patients); more patients had ongoing peripheral neuropathy in the A+AVD group (127 [19%] of 662) than in the ABVD group (59 [9%] of 659). Fewer secondary malignancies were reported with A+AVD (19 [3%] of 662) than with ABVD (29 [4%] of 659). More livebirths were reported in the A+AVD group (n=75) than in the ABVD group (n=50). INTERPRETATION: With 5 years of follow-up, A+AVD showed robust and durable improvement in progression-free survival versus ABVD, regardless of PET-2 status, and a consistent safety profile. On the basis of these findings, A+AVD should be preferred over ABVD for patients with previously untreated stage III or IV classical Hodgkin lymphoma. FUNDING: Millennium Pharmaceuticals (a wholly owned subsidiary of Takeda Pharmaceutical Company), and Seagen.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Brentuximab Vedotina/administración & dosificación , Enfermedad de Hodgkin/tratamiento farmacológico , Bleomicina/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Enfermedad de Hodgkin/mortalidad , Enfermedad de Hodgkin/patología , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Tomografía de Emisión de Positrones , Supervivencia sin Progresión , Vinblastina/administración & dosificación
6.
Evol Appl ; 13(7): 1673-1680, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32821277

RESUMEN

It is increasingly suggested that ecological and evolutionary sciences could inspire novel therapies against cancer but medical evidence of this remains scarce at the moment. The Achilles heel of conventional and targeted anticancer treatments is intrinsic or acquired resistance following Darwinian selection; that is, treatment toxicity places the surviving cells under intense evolutionary selective pressure to develop resistance. Here, we review a set of data that demonstrate that Darwinian principles derived from the "smoke detector" principle can instead drive the evolution of malignant cells toward a different trajectory. Specifically, long-term exposure of cancer cells to a strong alarm signal, generated by the DNA repair inhibitor AsiDNA, induces a stable new state characterized by a down-regulation of the targeted pathways and does not generate resistant clones. This property is due to the original mechanism of action of AsiDNA, which acts by overactivating a "false" signaling of DNA damage through DNA-PK and PARP enzymes, and is not observed with classical DNA repair inhibitors such as the PARP inhibitors. Long-term treatment with AsiDNA induces a new "alarm down" state in the tumor cells with decrease in NAD level and reactiveness to it. These results suggest that agonist drugs such as AsiDNA could promote a state-dependent tumor cell evolution by lowering their ability to respond to high "danger" signal. This analysis provides a compelling argument that evolutionary ecology could help drug design development in overcoming fundamental limitation of novel therapies against cancer due to the modification of the targeted tumor cell population during treatment.

7.
Leuk Lymphoma ; 61(12): 2931-2938, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32842815

RESUMEN

We investigate the impact of granulocyte-colony stimulating factor (G-CSF) primary prophylaxis (G-PP, N = 83) versus no G-PP (N = 579) on safety and efficacy of brentuximab vedotin plus doxorubicin, vinblastine, and dacarbazine (A + AVD) in the ECHELON-1 study of previously untreated stage III/IV classical Hodgkin lymphoma. G-PP was associated with lower incidence of ≥ grade 3 neutropenia (29% versus 70%) and febrile neutropenia (11% versus 21%). Fewer dose delays (35% versus 49%), reductions (20% versus 26%), and hospitalizations (29% versus 38%) were observed. Seven neutropenia-associated deaths occurred in the A + AVD arm; none received G-PP. A + AVD with G-PP was associated with decreased risk of a modified progression-free survival event by 26% compared with A + AVD alone (95% CI: 0.40-1.37). G-PP reduced the rate and severity of adverse events, including febrile neutropenia, reduced treatment delays, dose reductions, and discontinuations, and may thus improve efficacy outcomes. These data support G-PP for all patients treated with A + AVD.


Asunto(s)
Enfermedad de Hodgkin , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Brentuximab Vedotina , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Enfermedad de Hodgkin/tratamiento farmacológico , Humanos , Vinblastina/uso terapéutico
8.
Blood ; 135(10): 735-742, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-31945149

RESUMEN

The phase 3 ECHELON-1 study demonstrated that brentuximab vedotin (A) with doxorubicin, vinblastine, and dacarbazine (AVD; A+AVD) exhibited superior modified progression-free survival (PFS) vs doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) for frontline treatment of patients with stage III/IV classical Hodgkin lymphoma (cHL). Maturing positron emission tomography (PET)-adapted trial data highlight potential limitations of PET-adapted approaches, including toxicities with dose intensification and higher-than-expected relapse rates in PET scan after cycle 2 (PET2)-negative (PET2-) patients. We present an update of the ECHELON-1 study, including an exploratory analysis of 3-year PFS per investigator. A total of 1334 patients with stage III or IV cHL were randomized 1:1 to receive 6 cycles of A+AVD (n = 664) or ABVD (n = 670). Interim PET2 was required. At median follow-up of 37 months, 3-year PFS rates were 83.1% with A+AVD and 76.0% with ABVD; 3-year PFS rates in PET2- patients aged <60 years were 87.2% vs 81.0%, respectively. A beneficial trend in PET2+ patients aged <60 years on A+AVD was also observed, with a 3-year PFS rate of 69.2% vs 54.7% with ABVD. The benefit of A+AVD in the intent-to-treat population appeared independent of disease stage and prognostic risk factors. Upon continued follow-up, 78% of patients with peripheral neuropathy on A+AVD had either complete resolution or improvement compared with 83% on ABVD. These data highlight that A+AVD provides a durable efficacy benefit compared with ABVD for frontline stage III/IV cHL, consistent across key subgroups regardless of patient status at PET2, without need for treatment intensification or bleomycin exposure. This trial was registered at www.clinicaltrials.gov as #NCT01712490 (EudraCT no. 2011-005450-60).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Brentuximab Vedotina/administración & dosificación , Enfermedad de Hodgkin/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Bleomicina/uso terapéutico , Brentuximab Vedotina/efectos adversos , Dacarbazina/administración & dosificación , Dacarbazina/efectos adversos , Dacarbazina/uso terapéutico , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Doxorrubicina/uso terapéutico , Femenino , Estudios de Seguimiento , Enfermedad de Hodgkin/mortalidad , Enfermedad de Hodgkin/patología , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Análisis de Supervivencia , Resultado del Tratamiento , Vinblastina/administración & dosificación , Vinblastina/efectos adversos , Vinblastina/uso terapéutico
9.
Hematol Oncol ; 38(1): 67-73, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31724191

RESUMEN

BCD-020 is a proposed rituximab biosimilar, which has shown high similarity to rituximab in quality and nonclinical studies in vitro and in vivo. International multicenter clinical trial was conducted to compare efficacy and safety of BCD-020 and reference rituximab in adult (older than 18 years) patients with indolent lymphomas (follicular lymphoma grade 1-2, splenic marginal zone lymphoma, and nodal marginal zone lymphoma). Pharmacokinetics, pharmacodynamics, and immunogenicity were also studied. Patients with no previous biologic treatment for lymphoma were randomly assigned 1:1 to receive BCD-020 or comparator 375 mg/m2 for 4 weeks. Primary study outcome was day 50 overall response rate defined as complete or partial remission. Equivalence range was -20% to 20% for 95% CI for overall response rates difference. Secondary outcomes included adverse events, pharmacokinetics, pharmacodynamics, and immunogenicity. One hundred seventy-four patients were enrolled, 89 in BCD-020 arm and 85 in comparator arm. The overall response rate was 44.71% in BCD-020 arm and 41.89% in comparator arm. Limits of 95% confidence interval (CI) for difference of overall response rates between arms were (-12.62%-18.24%) showing equivalent efficacy. Sixty-one (68.54%) and 59 (69.41%) patients had at least one adverse event in BCD-020 arm or comparator arm, respectively. No unexpected adverse reactions were reported. Antidrug antibodies with no neutralizing activity were detected in two patients in comparator arm on day 14 further declining below detection threshold. Rituximab concentrations had equivalent pattern after intravenous administration of both drugs. Both drugs caused depletion of B-cells without significant influence on other blood cell lineages. In this study, we showed equivalent efficacy of BCD-020 and reference rituximab when used in patients with CD20-positive indolent lymphomas. We also confirmed pharmacokinetic equivalence of BCD-020 and reference rituximab. Safety profile, pharmacodynamics, and immunogenicity of BCD-020 were also comparable with those of reference rituximab.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Biosimilares Farmacéuticos/uso terapéutico , Linfoma de Células B de la Zona Marginal/tratamiento farmacológico , Linfoma Folicular/tratamiento farmacológico , Rituximab/uso terapéutico , Anciano , Antineoplásicos Inmunológicos/farmacocinética , Biosimilares Farmacéuticos/farmacocinética , Femenino , Estudios de Seguimiento , Humanos , Agencias Internacionales , Linfoma de Células B de la Zona Marginal/metabolismo , Linfoma de Células B de la Zona Marginal/patología , Linfoma Folicular/metabolismo , Linfoma Folicular/patología , Masculino , Persona de Mediana Edad , Pronóstico , Rituximab/farmacocinética , Distribución Tisular
10.
Neoplasia ; 21(9): 863-871, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31362243

RESUMEN

The Achilles heel of anticancer treatments is intrinsic or acquired resistance. Among many targeted therapies, the DNA repair inhibitors show limited efficacy due to rapid emergence of resistance. We examined evolution of cancer cells and tumors treated with AsiDNA, a new DNA repair inhibitor targeting all DNA break repair pathways. Effects of AsiDNA or Olaparib were analyzed in various cell lines. Frequency of AsiDNA- and olaparib-resistant clones was measured after 2 weeks of continuous treatment in KBM7 haploid cells. Cell survivals were also measured after one to six cycles of 1-week treatment and 1-week recovery in MDA-MB-231 and NCI-H446. Transcriptomes of cell populations recovering from cyclic treatments or mock treatment were compared. MDA-MB-231 xenografted models were treated with three cycles of AsiDNA to monitor the effects of treatment on tumor growth and transcriptional modifications. No resistant clones were selected after AsiDNA treatment (frequency < 3x10-8) in treatment conditions that generate resistance to olaparib at a frequency of 7.2x10-7 resistant clones per treated cell. Cyclic treatments promote cumulative sensitivity characterized by a higher mortality of cells having undergone previous treatment cycles. This sensitization was stable, and transcriptome analysis revealed a major gene downregulation with a specific overrepresentation of genes coding for targets of DNA-PK. Such changes were also detected in tumor models which showed impaired growth after cycles of AsiDNA treatment.


Asunto(s)
Antineoplásicos/administración & dosificación , Reparación del ADN , ADN/administración & dosificación , ADN/genética , Resistencia a Antineoplásicos , Animales , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Relación Dosis-Respuesta a Droga , Perfilación de la Expresión Génica , Haploidia , Xenoinjertos , Humanos , Ratones , Procesamiento Postranscripcional del ARN
11.
N Engl J Med ; 378(4): 331-344, 2018 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-29224502

RESUMEN

BACKGROUND: Brentuximab vedotin is an anti-CD30 antibody-drug conjugate that has been approved for relapsed and refractory Hodgkin's lymphoma. METHODS: We conducted an open-label, multicenter, randomized phase 3 trial involving patients with previously untreated stage III or IV classic Hodgkin's lymphoma, in which 664 were assigned to receive brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine (A+AVD) and 670 were assigned to receive doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD). The primary end point was modified progression-free survival (the time to progression, death, or noncomplete response and use of subsequent anticancer therapy) as adjudicated by an independent review committee. The key secondary end point was overall survival. RESULTS: At a median follow-up of 24.6 months, 2-year modified progression-free survival rates in the A+AVD and ABVD groups were 82.1% (95% confidence interval [CI], 78.8 to 85.0) and 77.2% (95% CI, 73.7 to 80.4), respectively, a difference of 4.9 percentage points (hazard ratio for an event of progression, death, or modified progression, 0.77; 95% CI, 0.60 to 0.98; P=0.04). There were 28 deaths with A+AVD and 39 with ABVD (hazard ratio for interim overall survival, 0.73 [95% CI, 0.45 to 1.18]; P=0.20) [corrected]. All secondary efficacy end points trended in favor of A+AVD. Neutropenia occurred in 58% of the patients receiving A+AVD and in 45% of those receiving ABVD; in the A+AVD group, the rate of febrile neutropenia was lower among the 83 patients who received primary prophylaxis with granulocyte colony-stimulating factor than among those who did not (11% vs. 21%). Peripheral neuropathy occurred in 67% of patients in the A+AVD group and in 43% of patients in the ABVD group; 67% of patients in the A+AVD group who had peripheral neuropathy had resolution or improvement at the last follow-up visit. Pulmonary toxicity of grade 3 or higher was reported in less than 1% of patients receiving A+AVD and in 3% of those receiving ABVD. Among the deaths that occurred during treatment, 7 of 9 in the A+AVD group were associated with neutropenia and 11 of 13 in the ABVD group were associated with pulmonary-related toxicity. CONCLUSIONS: A+AVD had superior efficacy to ABVD in the treatment of patients with advanced-stage Hodgkin's lymphoma, with a 4.9 percentage-point lower combined risk of progression, death, or noncomplete response and use of subsequent anticancer therapy at 2 years. (Funded by Millennium Pharmaceuticals and Seattle Genetics; ECHELON-1 ClinicalTrials.gov number, NCT01712490 ; EudraCT number, 2011-005450-60 .).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedad de Hodgkin/tratamiento farmacológico , Inmunoconjugados/administración & dosificación , Factores Inmunológicos/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bleomicina/administración & dosificación , Brentuximab Vedotina , Dacarbazina/administración & dosificación , Supervivencia sin Enfermedad , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Enfermedad de Hodgkin/mortalidad , Humanos , Inmunoconjugados/efectos adversos , Factores Inmunológicos/efectos adversos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neutropenia/inducido químicamente , Tasa de Supervivencia , Vinblastina/administración & dosificación , Adulto Joven
12.
Circulation ; 136(8): 747-761, 2017 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-28611091

RESUMEN

BACKGROUND: Cardiovascular diseases remain the predominant cause of death worldwide, with the prevalence of heart failure continuing to increase. Despite increased knowledge of the metabolic alterations that occur in heart failure, novel therapies to treat the observed metabolic disturbances are still lacking. METHODS: Mice were subjected to pressure overload by means of angiotensin-II infusion or transversal aortic constriction. MicroRNA-146a was either genetically or pharmacologically knocked out or genetically overexpressed in cardiomyocytes. Furthermore, overexpression of dihydrolipoyl succinyltransferase (DLST) in the murine heart was performed by means of an adeno-associated virus. RESULTS: MicroRNA-146a was upregulated in whole heart tissue in multiple murine pressure overload models. Also, microRNA-146a levels were moderately increased in left ventricular biopsies of patients with aortic stenosis. Overexpression of microRNA-146a in cardiomyocytes provoked cardiac hypertrophy and left ventricular dysfunction in vivo, whereas genetic knockdown or pharmacological blockade of microRNA-146a blunted the hypertrophic response and attenuated cardiac dysfunction in vivo. Mechanistically, microRNA-146a reduced its target DLST-the E2 subcomponent of the α-ketoglutarate dehydrogenase complex, a rate-controlling tricarboxylic acid cycle enzyme. DLST protein levels significantly decreased on pressure overload in wild-type mice, paralleling a decreased oxidative metabolism, whereas DLST protein levels and hence oxidative metabolism were partially maintained in microRNA-146a knockout mice. Moreover, overexpression of DLST in wild-type mice protected against cardiac hypertrophy and dysfunction in vivo. CONCLUSIONS: Altogether we show that the microRNA-146a and its target DLST are important metabolic players in left ventricular dysfunction.


Asunto(s)
Aciltransferasas/biosíntesis , Cardiomegalia/metabolismo , Regulación Enzimológica de la Expresión Génica , MicroARNs/antagonistas & inhibidores , MicroARNs/biosíntesis , Disfunción Ventricular Izquierda/metabolismo , Aciltransferasas/genética , Animales , Animales Recién Nacidos , Cardiomegalia/genética , Cardiomegalia/prevención & control , Células Cultivadas , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , MicroARNs/genética , Miocitos Cardíacos/metabolismo , Ratas , Ratas Endogámicas Lew , Disfunción Ventricular Izquierda/genética , Disfunción Ventricular Izquierda/prevención & control
13.
Mol Cell ; 65(3): 504-514.e4, 2017 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-28157507

RESUMEN

Transcription starts with the assembly of pre-initiation complexes on promoters followed by their opening. Current models suggest that class II gene transcription requires ATP and the TFIIH XPB subunit to open a promoter. Here, we observe that XPB depletion surprisingly leaves transcription virtually intact. In contrast, inhibition of XPB ATPase activity affects transcription, revealing that mRNA expression paradoxically accommodates the absence of XPB while being sensitive to the inhibition of its ATPase activity. The XPB-depleted TFIIH complex is recruited to active promoters and contributes to transcription. We finally demonstrate that the XPB ATPase activity is only used to relieve a transcription initiation block imposed by XPB itself. In the absence of this block, transcription initiation can take place without XPB ATPase activity. These results suggest that a helicase is dispensable for mRNA transcription, thereby unifying the mechanism of promoter DNA opening for the three eukaryotic RNA polymerases.


Asunto(s)
ADN Helicasas/genética , ADN Helicasas/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Transcripción Genética , Adenosina Trifosfatasas/metabolismo , Línea Celular , Perfilación de la Expresión Génica/métodos , Humanos , Mutación , Regiones Promotoras Genéticas , Análisis de Secuencia de ARN/métodos , Factor de Transcripción TFIIH/química , Factor de Transcripción TFIIH/metabolismo
14.
Cell Mol Life Sci ; 72(11): 2177-86, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25681868

RESUMEN

To safeguard the genome from the accumulation of deleterious effects arising from DNA lesions, cells developed several DNA repair mechanisms that remove specific types of damage from the genome. Among them, Nucleotide Excision Repair (NER) is unique in its ability to remove a very broad spectrum of lesions, the most important of which include UV-induced damage, bulky chemical adducts and some forms of oxidative damage. Two sub-pathways exist in NER; Transcription-Coupled Repair (TC-NER) removes lesion localized exclusively in transcribed genes while Global Genome Repair (GG-NER) removes lesions elsewhere. In TC- or GG-NER, more than 30 proteins detect, open, incise and resynthesize DNA. Intriguingly, half of them are involved in the detection of DNA damage, implying that this is a crucial repair step requiring a high level of regulation. We review here the complex damage recognition step of GG-NER with a focus on post-translational modifications that help the comings and goings of several protein complexes on the same short damaged DNA locus.


Asunto(s)
Daño del ADN/genética , Reparación del ADN/genética , ADN/genética , Genoma/genética , Proteínas de Unión al ADN/genética , Humanos , Procesamiento Proteico-Postraduccional/genética , Factor de Transcripción TFIIH/genética , Transcripción Genética , Xerodermia Pigmentosa/genética , Proteína de la Xerodermia Pigmentosa del Grupo A/genética
15.
Sci Technol Adv Mater ; 16(4): 044601, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27877819

RESUMEN

Carbon fluoroxide (CFO) nanoparticles (NPs) produced from silicon carbide wafers are used as both fluorescent probes and sonosensitizers for theranostic application. In vitro cell tests were carried out to investigate the feasibility of ultrasound-based therapy with the use of the CFO NPs. The NPs that penetrated inside the cells were shown to provoke cell destruction after application of an ultrasound treatment. No significant toxic effect was observed when the cells were treated with NP concentrations up to 0.5 mg ml-1 without applying ultrasound treatment. The obtained results open a new way toward cancer therapy strategies.

16.
J Cell Biol ; 206(5): 589-98, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25154395

RESUMEN

In nucleotide excision repair (NER), damage recognition by XPC-hHR23b is described as a critical step in the formation of the preincision complex (PInC) further composed of TFIIH, XPA, RPA, XPG, and ERCC1-XPF. To obtain new molecular insights into the assembly of the PInC, we analyzed its formation independently of DNA damage by using the lactose operator/repressor reporter system. We observed a sequential and ordered self-assembly of the PInC operating upon immobilization of individual NER factors on undamaged chromatin and mimicking that functioning on a bona fide NER substrate. We also revealed that the recruitment of the TFIIH subunit TTDA, involved in trichothiodystrophy group A disorder (TTD-A), was key in the completion of the PInC. TTDA recruits XPA through its first 15 amino acids, depleted in some TTD-A patients. More generally, these results show that proteins forming large nuclear complexes can be recruited sequentially on chromatin in the absence of their natural DNA target and with no reciprocity in their recruitment.


Asunto(s)
Cromatina/metabolismo , Línea Celular Tumoral , Daño del ADN , Reparación del ADN , Enzimas Reparadoras del ADN/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Endonucleasas/metabolismo , Humanos , Proteínas Inmovilizadas/química , Proteínas Inmovilizadas/metabolismo , Proteínas Nucleares/metabolismo , Dominios y Motivos de Interacción de Proteínas , Multimerización de Proteína , Transporte de Proteínas , Factor de Transcripción TFIIH/metabolismo , Factores de Transcripción/metabolismo , Proteína de la Xerodermia Pigmentosa del Grupo A/química , Proteína de la Xerodermia Pigmentosa del Grupo A/metabolismo
17.
Cardiovasc Res ; 104(1): 61-71, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25103110

RESUMEN

AIMS: The overloaded heart remodels by cardiomyocyte hypertrophy and interstitial fibrosis, which contributes to the development of heart failure. Signalling via the TGFß-pathway is crucial for this remodelling. Here we tested the hypothesis that microRNAs in the overloaded heart regulate this remodelling process via inhibition of the TGFß-pathway. METHODS AND RESULTS: We show that the miRNA-15 family, which we found to be up-regulated in the overloaded heart in multiple species, inhibits the TGFß-pathway by targeting of TGFBR1 and several other genes within this pathway directly or indirectly, including p38, SMAD3, SMAD7, and endoglin. Inhibition of miR-15b by subcutaneous injections of LNA-based antimiRs in C57BL/6 mice subjected to transverse aorta constriction aggravated fibrosis and to a lesser extent also hypertrophy. CONCLUSION: We identified the miR-15 family as a novel regulator of cardiac hypertrophy and fibrosis acting by inhibition of the TGFß-pathway.


Asunto(s)
Cardiomegalia/metabolismo , Cardiomiopatías/metabolismo , MicroARNs/metabolismo , Miocitos Cardíacos/metabolismo , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Remodelación Ventricular , Regiones no Traducidas 3' , Animales , Células COS , Cardiomegalia/genética , Cardiomegalia/patología , Cardiomegalia/fisiopatología , Cardiomiopatías/genética , Cardiomiopatías/patología , Cardiomiopatías/fisiopatología , Estudios de Casos y Controles , Chlorocebus aethiops , Modelos Animales de Enfermedad , Fibrosis , Células Hep G2 , Humanos , Ratones Endogámicos C57BL , MicroARNs/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Ratas Transgénicas , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/genética , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Proteína smad3/genética , Proteína smad3/metabolismo , Proteína smad7/genética , Proteína smad7/metabolismo , Transfección , Regulación hacia Arriba , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
18.
Nanoscale Res Lett ; 9(1): 94, 2014 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-24565261

RESUMEN

Silicon nanoparticles (Si NPs) with a diameter size ranging from 4 to 8 nm were successfully fabricated. They exhibit a visible photoluminescence (PL) due to the quantum confinement effect. Chemical functionalization of these Si NPs with alkyl groups allowed to homogeneously disperse them in nonpolar liquids (NPLs). In comparison to most of literature results for Si NPs, an important PL peak position variation with temperature (almost 1 meV/K) was obtained from 303 to 390 K. The influence of the liquid viscosity on the peak positions is also presented. These variations are discussed considering energy transfer between nanoparticles. The high PL thermal sensitivity of the alkyl-capped Si NPs paves the way for their future application as nanothermometers.

19.
Chem Biol ; 21(3): 398-407, 2014 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-24508195

RESUMEN

Nucleotide excision repair (NER) removes DNA lesions resulting from exposure to UV irradiation or chemical agents such as platinum-based drugs used as anticancer molecules. Pharmacological inhibition of NER is expected to enhance chemosensitivity but nontoxic NER inhibitors are rare. Using a drug repositioning approach, we identify spironolactone (SP), an antagonist of aldosterone, as a potent NER inhibitor. We found that SP promotes a rapid and reversible degradation of XPB, a subunit of transcription/repair factor TFIIH. Such degradation depends both on ubiquitin-activating enzyme and on the 26S proteasome. Supplementation of extracts from SP-treated cells with purified TFIIH restored TFIIH-dependent repair and transcription activities in vitro, demonstrating the specific impact of SP on two fundamental functions of TFIIH. Finally, SP potentiated the cytotoxicity of platinum derivatives toward tumor cells, making it a potential therapeutic and research tool.


Asunto(s)
Antineoplásicos/farmacología , Cisplatino/farmacología , Reparación del ADN/efectos de los fármacos , Espironolactona/farmacología , Factor de Transcripción TFIIH/metabolismo , Antineoplásicos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cisplatino/química , Daño del ADN/efectos de la radiación , Regulación hacia Abajo/efectos de los fármacos , Células HCT116 , Células HeLa , Humanos , Complejo de la Endopetidasa Proteasomal/metabolismo , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Espironolactona/química , Factor de Transcripción TFIIH/química , Transcripción Genética/efectos de los fármacos , Enzimas Activadoras de Ubiquitina/metabolismo , Rayos Ultravioleta
20.
J Cell Biol ; 196(6): 681-8, 2012 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-22431748

RESUMEN

The recognition of helix-distorting deoxyribonucleic acid (DNA) lesions by the global genome nucleotide excision repair subpathway is performed by the XPC-RAD23-CEN2 complex. Although it has been established that Rad23 homologs are essential to protect XPC from proteasomal degradation, it is unclear whether RAD23 proteins have a direct role in the recognition of DNA damage. In this paper, we show that the association of XPC with ultraviolet-induced lesions was impaired in the absence of RAD23 proteins. Furthermore, we show that RAD23 proteins rapidly dissociated from XPC upon binding to damaged DNA. Our data suggest that RAD23 proteins facilitate lesion recognition by XPC but do not participate in the downstream DNA repair process.


Asunto(s)
Daño del ADN , Proteínas de Unión al ADN/metabolismo , Animales , Línea Celular , Núcleo Celular/metabolismo , ADN/metabolismo , Reparación del ADN , Proteínas de Unión al ADN/genética , Humanos , Ratones
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