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1.
iScience ; 26(7): 106998, 2023 Jul 21.
Article in English | MEDLINE | ID: mdl-37534176

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-36670096

ABSTRACT

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.


Subject(s)
DNA Damage , DNA Repair , Chromatin/genetics , Transcription, Genetic , RNA Polymerase II/genetics , RNA Polymerase II/metabolism , RNA, Messenger/genetics
3.
Biodivers Data J ; 10: e76100, 2022.
Article in English | MEDLINE | ID: mdl-35095297

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-34759729

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-34048680

ABSTRACT

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.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Brentuximab Vedotin/administration & dosage , Hodgkin Disease/drug therapy , Bleomycin/administration & dosage , Doxorubicin/administration & dosage , Female , Follow-Up Studies , Hodgkin Disease/mortality , Hodgkin Disease/pathology , Humans , Male , Middle Aged , Neoplasm Staging , Positron-Emission Tomography , Progression-Free Survival , Vinblastine/administration & dosage
6.
Evol Appl ; 13(7): 1673-1680, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32821277

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-32842815

ABSTRACT

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.


Subject(s)
Hodgkin Disease , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Brentuximab Vedotin , Granulocyte Colony-Stimulating Factor/therapeutic use , Hodgkin Disease/drug therapy , Humans , Vinblastine/therapeutic use
8.
Blood ; 135(10): 735-742, 2020 03 05.
Article in English | MEDLINE | ID: mdl-31945149

ABSTRACT

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).


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Brentuximab Vedotin/administration & dosage , Hodgkin Disease/drug therapy , Adult , Aged , Aged, 80 and over , Bleomycin/therapeutic use , Brentuximab Vedotin/adverse effects , Dacarbazine/administration & dosage , Dacarbazine/adverse effects , Dacarbazine/therapeutic use , Doxorubicin/administration & dosage , Doxorubicin/adverse effects , Doxorubicin/therapeutic use , Female , Follow-Up Studies , Hodgkin Disease/mortality , Hodgkin Disease/pathology , Humans , Intention to Treat Analysis , Male , Middle Aged , Neoplasm Staging , Survival Analysis , Treatment Outcome , Vinblastine/administration & dosage , Vinblastine/adverse effects , Vinblastine/therapeutic use
9.
Hematol Oncol ; 38(1): 67-73, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31724191

ABSTRACT

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.


Subject(s)
Antineoplastic Agents, Immunological/therapeutic use , Biosimilar Pharmaceuticals/therapeutic use , Lymphoma, B-Cell, Marginal Zone/drug therapy , Lymphoma, Follicular/drug therapy , Rituximab/therapeutic use , Aged , Antineoplastic Agents, Immunological/pharmacokinetics , Biosimilar Pharmaceuticals/pharmacokinetics , Female , Follow-Up Studies , Humans , International Agencies , Lymphoma, B-Cell, Marginal Zone/metabolism , Lymphoma, B-Cell, Marginal Zone/pathology , Lymphoma, Follicular/metabolism , Lymphoma, Follicular/pathology , Male , Middle Aged , Prognosis , Rituximab/pharmacokinetics , Tissue Distribution
10.
Neoplasia ; 21(9): 863-871, 2019 09.
Article in English | MEDLINE | ID: mdl-31362243

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/administration & dosage , DNA Repair , DNA/administration & dosage , DNA/genetics , Drug Resistance, Neoplasm , Animals , Cell Line, Tumor , Cell Proliferation , Cell Survival , Dose-Response Relationship, Drug , Gene Expression Profiling , Haploidy , Heterografts , Humans , Mice , RNA Processing, Post-Transcriptional
11.
N Engl J Med ; 378(4): 331-344, 2018 01 25.
Article in English | MEDLINE | ID: mdl-29224502

ABSTRACT

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 .).


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Hodgkin Disease/drug therapy , Immunoconjugates/administration & dosage , Immunologic Factors/administration & dosage , Adolescent , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bleomycin/administration & dosage , Brentuximab Vedotin , Dacarbazine/administration & dosage , Disease-Free Survival , Doxorubicin/administration & dosage , Female , Follow-Up Studies , Hodgkin Disease/mortality , Humans , Immunoconjugates/adverse effects , Immunologic Factors/adverse effects , Male , Middle Aged , Neoplasm Staging , Neutropenia/chemically induced , Survival Rate , Vinblastine/administration & dosage , Young Adult
12.
Circulation ; 136(8): 747-761, 2017 Aug 22.
Article in English | MEDLINE | ID: mdl-28611091

ABSTRACT

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.


Subject(s)
Acyltransferases/biosynthesis , Cardiomegaly/metabolism , Gene Expression Regulation, Enzymologic , MicroRNAs/antagonists & inhibitors , MicroRNAs/biosynthesis , Ventricular Dysfunction, Left/metabolism , Acyltransferases/genetics , Animals , Animals, Newborn , Cardiomegaly/genetics , Cardiomegaly/prevention & control , Cells, Cultured , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , MicroRNAs/genetics , Myocytes, Cardiac/metabolism , Rats , Rats, Inbred Lew , Ventricular Dysfunction, Left/genetics , Ventricular Dysfunction, Left/prevention & control
13.
Mol Cell ; 65(3): 504-514.e4, 2017 Feb 02.
Article in English | MEDLINE | ID: mdl-28157507

ABSTRACT

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.


Subject(s)
DNA Helicases/genetics , DNA Helicases/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Transcription, Genetic , Adenosine Triphosphatases/metabolism , Cell Line , Gene Expression Profiling/methods , Humans , Mutation , Promoter Regions, Genetic , Sequence Analysis, RNA/methods , Transcription Factor TFIIH/chemistry , Transcription Factor TFIIH/metabolism
14.
Cell Mol Life Sci ; 72(11): 2177-86, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25681868

ABSTRACT

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.


Subject(s)
DNA Damage/genetics , DNA Repair/genetics , DNA/genetics , Genome/genetics , DNA-Binding Proteins/genetics , Humans , Protein Processing, Post-Translational/genetics , Transcription Factor TFIIH/genetics , Transcription, Genetic , Xeroderma Pigmentosum/genetics , Xeroderma Pigmentosum Group A Protein/genetics
15.
Sci Technol Adv Mater ; 16(4): 044601, 2015 Aug.
Article in English | MEDLINE | ID: mdl-27877819

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-25154395

ABSTRACT

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.


Subject(s)
Chromatin/metabolism , Cell Line, Tumor , DNA Damage , DNA Repair , DNA Repair Enzymes/metabolism , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , Endonucleases/metabolism , Humans , Immobilized Proteins/chemistry , Immobilized Proteins/metabolism , Nuclear Proteins/metabolism , Protein Interaction Domains and Motifs , Protein Multimerization , Protein Transport , Transcription Factor TFIIH/metabolism , Transcription Factors/metabolism , Xeroderma Pigmentosum Group A Protein/chemistry , Xeroderma Pigmentosum Group A Protein/metabolism
17.
Cardiovasc Res ; 104(1): 61-71, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-25103110

ABSTRACT

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.


Subject(s)
Cardiomegaly/metabolism , Cardiomyopathies/metabolism , MicroRNAs/metabolism , Myocytes, Cardiac/metabolism , Signal Transduction , Transforming Growth Factor beta/metabolism , Ventricular Remodeling , 3' Untranslated Regions , Animals , COS Cells , Cardiomegaly/genetics , Cardiomegaly/pathology , Cardiomegaly/physiopathology , Cardiomyopathies/genetics , Cardiomyopathies/pathology , Cardiomyopathies/physiopathology , Case-Control Studies , Chlorocebus aethiops , Disease Models, Animal , Fibrosis , Hep G2 Cells , Humans , Mice, Inbred C57BL , MicroRNAs/genetics , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Rats, Transgenic , Receptor, Transforming Growth Factor-beta Type I , Receptors, Transforming Growth Factor beta/genetics , Receptors, Transforming Growth Factor beta/metabolism , Smad3 Protein/genetics , Smad3 Protein/metabolism , Smad7 Protein/genetics , Smad7 Protein/metabolism , Transfection , Up-Regulation , p38 Mitogen-Activated Protein Kinases/genetics , p38 Mitogen-Activated Protein Kinases/metabolism
18.
Nanoscale Res Lett ; 9(1): 94, 2014 Feb 24.
Article in English | MEDLINE | ID: mdl-24565261

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-24508195

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/pharmacology , Cisplatin/pharmacology , DNA Repair/drug effects , Spironolactone/pharmacology , Transcription Factor TFIIH/metabolism , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Cisplatin/chemistry , DNA Damage/radiation effects , Down-Regulation/drug effects , HCT116 Cells , HeLa Cells , Humans , Proteasome Endopeptidase Complex/metabolism , Protein Subunits/genetics , Protein Subunits/metabolism , Spironolactone/chemistry , Transcription Factor TFIIH/chemistry , Transcription, Genetic/drug effects , Ubiquitin-Activating Enzymes/metabolism , Ultraviolet Rays
20.
J Cell Biol ; 196(6): 681-8, 2012 Mar 19.
Article in English | MEDLINE | ID: mdl-22431748

ABSTRACT

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.


Subject(s)
DNA Damage , DNA-Binding Proteins/metabolism , Animals , Cell Line , Cell Nucleus/metabolism , DNA/metabolism , DNA Repair , DNA-Binding Proteins/genetics , Humans , Mice
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