Aortic valve regurgitation (AR) imposes a severe volume overload to the left ventricle (LV) which results in dilation, eccentric hypertrophy and eventually loss of function. Little is known about the impact of AR on LV gene expression. We therefore conducted a gene expression profiling study in the LV of male Wistar rats with chronic (9 months) and severe AR.
Multiple short-chain dehydrogenases/reductases are regulated in pathological cardiac hypertrophy.
Sex
View SamplesLoss of function of the tumor suppressor BRCA1 (Breast Cancer 1) protein is responsible for numerous familial and sporadic breast cancers. We previously identified PABP1 as a novel BRCA1 partner and showed that BRCA1 modulates translation through its interaction with PABP1. We showed that the global translation was diminished in BRCA1-depleted cells and increased in BRCA1-overexpressing cells. Our findings raised the question whether BRCA1 affects translation of all cytoplasmic cellular mRNAs or whether it specifically targets a subset of mRNAs.
BRCA1-Dependent Translational Regulation in Breast Cancer Cells.
Cell line
View SamplesSteroid hormones regulate essential physiological processes and inadequate levels are associated with various pathological conditions. In testosterone-producing Leydig cells, steroidogenesis is strongly stimulated by LH via its receptor leading to increased cAMP production and expression of the steroidogenic acute regulatory (STAR) protein, which is essential for the initiation of steroidogenesis. Leydig cell steroidogenesis then passively decreases following the rapid degradation of cAMP into AMP by phosphodiesterases. In this study, we show that AMP-activated protein kinase (AMPK) is activated following cAMP breakdown in MA-10 and MLTC-1 Leydig cells. Activated AMPK then actively inhibits cAMP-induced steroidogenesis by repressing the expression of key regulators of steroidogenesis including Star and Nr4a1. Similar results were obtained in Y-1 adrenal cells and in the constitutive steroidogenic cell line R2C. Our data identify AMPK as an active repressor of steroid hormone biosynthesis in steroidogenic cells that is essential to preserve cellular energy and prevent excess steroid production.
A cell-autonomous molecular cascade initiated by AMP-activated protein kinase represses steroidogenesis.
Specimen part, Treatment
View SamplesWe have previously shown that Il1a-knockout (KO) mice exhibit rapid (at day 1) and persistent improvements in locomotion associated with reduced lesion volume compared with Il1b-KO mice and C57BL/6 controls after traumatic spinal cord injury (SCI). To investigate the mechanism by which Il1a mediates its detrimental effect, we analyzed the transcriptome of the injured spinal cord of Il1a-KO, Il1b-KO and C57BL/6 mice at 24 hours after SCI using GeneChip microarrays.
IL-1α Gene Deletion Protects Oligodendrocytes after Spinal Cord Injury through Upregulation of the Survival Factor Tox3.
Specimen part
View SamplesCorrelates of immune mediated protection to most viral and cancer vaccines are still unknown. This impedes the development of novel vaccines to incurable diseases such as HIV and cancer. In this study, we have used functional genomics and polychromatic flow cytometry to define the signature of the immune response to the yellow fever (YF) vaccine 17D (YF17D) in a cohort of forty volunteers followed for up to one year after vaccination. We show that immunization with YF17D leads to an integrated immune response that includes several effector arms of innate immunity including complement, the inflammasome and interferons, as well as adaptive immunity as shown by an early T cell response followed by a brisk and variable B cell response. Development of these responses is preceded, as demonstrated in three independent vaccination trials and in a novel in vitro system of primary immune responses (Modular IMmune In vitro Construct (MIMIC) system), by the coordinated up-regulation of transcripts for specific transcription factors including STAT1, IRF7 and ETS2 that are upstream of the different effector arms of the immune response. These results clearly show that the immune response to a strong vaccine is preceded by coordinated induction of masters transcription factors, that lead to the development of a broad, polyfunctional and persistent immune response that integrates all effector cells of the immune system.
Yellow fever vaccine induces integrated multilineage and polyfunctional immune responses.
No sample metadata fields
View SamplesMultiple myeloma (MM) is a currently incurable malignancy of antibody-secreting plasma cells. Long non-coding RNAs (lncRNAs) have been recognised as an important class of regulatory molecules which are increasingly implicated in tumorigenesis. While recent studies have demonstrated changes in expression of lncRNAs in MM, the functional significance and molecular pathways downstream of these changes remain poorly characterised. In this study we have performed CRISPR-mediated deletion of the locus encoding the lncRNA Colorectal Neoplasia Differentially Expressed (CRNDE), a known oncogenic lncRNA that is overexpressed in plasma cells of MM patients and is a marker of poor prognosis. We found that CRISPR-mediated deletion of the CRNDE locus in MM cells decreases proliferation and adhesion properties, increases sensitivity to Dexamethasone and reduces tumour growth in an in vivo xenograft model. Transcriptomic profiling in CRNDE-deleted MM cells demonstrated that CRNDE activates expression of a number of genes previously implicated in the aetiology of MM, including IL6R. We further demonstrate that deletion of the CRNDE locus diminishes IL6 signalling and proliferative responses in MM cells. Altogether this study reveals the IL6 signalling pathway as a novel mechanism by which CRNDE impacts upon MM cell growth and disease progression.
The long non-coding RNA CRNDE regulates growth of multiple myeloma cells via an effect on IL6 signalling.
Cell line
View SamplesWe used microarrays to detail the global gene expression signature of PDAC and to identify distinct up- and down-regulated transcripts in these tumors compared to control pancreas. We also established from this dataset the metabolic signature of PDAC in order to define new metabolic therapeutic target for pancreatic cancer.
Cholesterol uptake disruption, in association with chemotherapy, is a promising combined metabolic therapy for pancreatic adenocarcinoma.
Sex, Age, Specimen part
View SamplesAcute Myeloid Leukemia (AML) is frequently associated with mutations of NPM1 (NPM1c+) and even if considered to be of better prognosis for younger patients, relapse is frequent and outcome remains poor for elder patients with a need for novel treatment strategies. Differentiation-based therapy by all trans retinoic acid (ATRA) combined with arsenic trioxide (ATO) induce proteasomal degradation of NPM1c protein, NPM1 nuclear re localization, differentiation and apoptosis in NPM1c+ cells and blast clearance in relapsed/refractory AML patients. In line, the XPO1 inhibitor Selinexor showed similar results in vitro associated with down regulation of a specific HOX gene signature. BET inhibitors (BETi) OTX015 (MK-8628) and JQ1 yield antileukemic activity and here we demonstrate their effects in NPM1c+ leukemia cells compared to ATO+ATRA and Selinexor. Compared to ATO+ATRA and Selinexor, BRDi induced TP53 independent apoptosis, differentiation, proteasomal NPM1c degradation and nuclear relocalization in NPM1c+ OCI-AML3 cell line and to different extend in patient derived blast cells. As ATO+ATRA and Selinexor had significant biological activity in NPM1c+ cell line IMS-M2, these cells were resistant to BETi exposure, except for nuclear re localization of NPM1 which is a general phenomenon upon treatment with all three drug types. Gene profiling revealed that BRDi downregulate a BRD specific core gene signature in OCI-AML3 and IMS-M2 cells but IMS-M2 cells yield a transcriptional resistance signature including upregulation of the Wnt/beta-catenin pathway. HOX gene clusters in OCI-AML3 cells and IMS-M2 cells are heterogeneously regulated by BETi and are down regulated by ATO+ATRA in line with results reported for Selinexor treatment. Taken together, our preclinical results encourage clinical testing of ATO+ATRA, Selinexor and BRDi in NPM1c+ AML patients.
No associated publication
Cell line, Compound
View SamplesInvariant natural killer T cells (iNKT) expressing the retinoic acid receptor-related orphan receptor γt (RORγt) and producing IL-17 represent a minor subset of CD1d-restricted iNKT cells (iNKT17) in C57BL/6J (B6) mice. We aimed in this study to define the reasons for their low distribution and the sequence of events accompanying their normal thymic development. We found that RORγt+ iNKT cells have higher proliferation potential and a greater propensity to apoptosis than RORγt- iNKT cells. These cells do not likely reside in the thymus indicating that thymus emigration, and higher apoptosis potential, could contribute to RORγt+ iNKT cell reduced thymic distribution. Ontogeny studies suggest that mature HSAlow RORγt+ iNKT cells might develop through developmental stages defined by a differential expression of CCR6 and CD138 during which RORγt expression and IL-17 production capabilities are progressively acquired. Finally, we found that RORγt+ iNKT cells perceive a strong TCR signal that could contribute to their entry into a specific Th17 like developmental program influencing their survival and migration. Overall, our study proposes a hypothetical thymic developmental sequence for iNKT17 cells, which could be of great use to study molecular mechanisms regulating this developmental program.
Characterization of the developmental landscape of murine RORγt+ iNKT cells.
No sample metadata fields
View SamplesCF's physiopathology is poorly explained by the mutation alone. The oxydative stress could be a major factor of this illness . Study its impact on transcriptome's CF cell line could be ameliorate our understanding of the evolution of cystic fibrosis.
Oxidative stress modulates the expression of genes involved in cell survival in ΔF508 cystic fibrosis airway epithelial cells.
Cell line, Treatment
View Samples