Gene expression in NPM1 wildtype and mutated AML patients with high or low hsa_circ_0075001 expression
Circular RNAs of the nucleophosmin (NPM1) gene in acute myeloid leukemia.
Specimen part, Disease, Disease stage
View SamplesRecently, the p53-miR-34a network was identified to play an important role in tumorigenesis. As in acute myeloid leukemia with complex karyotype (CK-AML) TP53 alterations are the most common known molecular lesion, we further analyzed the p53-miR-34a axis in CK-AML with known TP53 status. Clinically, low miR-34a expression and TP53 alterations predicted for chemotherapy resistance and inferior outcome. Notably, in TP53unaltered CK-AML high miR-34a expression predicted for inferior overall survival (OS), whereas in TP53biallelic altered CK-AML high miR-34a expression pointed to better OS.
Altered miRNA and gene expression in acute myeloid leukemia with complex karyotype identify networks of prognostic relevance.
Disease
View SamplesThis SuperSeries is composed of the SubSeries listed below.
BCAT1 restricts αKG levels in AML stem cells leading to IDHmut-like DNA hypermethylation.
Cell line, Treatment
View SamplesThe branched chain amino acid (BCAA) pathway and high levels of BCAA transaminase 1 (BCAT1) have recently been associated with aggressiveness in several cancer entities. However, the mechanistic role of BCAT1 in this process remains largely uncertain. By performing high-resolution proteomic analysis of human acute myeloid leukaemia (AML) stem cell (LSC) and non-LSC populations, we found the BCAA pathway enriched and BCAT1 overexpressed in LSCs. We show that BCAT1, which transfers -amino groups from BCAAs to -ketoglutarate (KG), is a critical regulator of intracellular KG homeostasis. Next to its role in the tricarboxylic acid (TCA) cycle KG is an essential co-factor for KG-dependent dioxygenases such as EGLN1 and the TET family of DNA demethylases. Knockdown of BCAT1 in leukaemia cells caused accumulation of KG leading to HIF1a protein degradation mediated by EGLN1. This resulted in a growth and survival defect and abrogated leukaemia-initiating potential. In contrast, overexpression (OE) of BCAT1 in leukaemia cells decreased intracellular KG levels and caused DNA hypermethylation via altered TET activity. BCAT1high AMLs displayed a DNA hypermethylation phenotype similar to cases carrying mutant isocitrate dehydrogenase (IDHmut), in which TET2 is inhibited by the oncometabolite 2-hydroxyglutarate. High levels of BCAT1 strongly correlate with shorter overall survival in IDHwtTET2wt, but not IDHmut or TET2mut AMLs. Gene sets characteristic for IDHmut AMLs were enriched in IDHwtTETwtBCAT1high patient samples. BCAT1high AMLs showed robust enrichment for LSC signatures and paired sample analysis revealed a significant increase of BCAT1 levels upon disease relapse. In summary, by limiting intracellular KG, BCAT1 links BCAA catabolism to HIF1a stability and regulation of the epigenomic landscape. Our results suggest the BCAA-BCAT1-KG pathway as a therapeutic target to compromise LSC function in IDHwtTET2wt AML patients.
BCAT1 restricts αKG levels in AML stem cells leading to IDHmut-like DNA hypermethylation.
Treatment
View SamplesSystems biology has the potential to identify gene signatures associated with vaccine immunogenicity or protective efficacy. The main objective of our study was to identify optimal post-vaccination time points for evaluating blood RNA-expression profiles in recipients of the candidate tuberculosis vaccine M72/AS01. In this phase II open-label study (NCT01669096), healthy Bacillus Calmette-Gurin (BCG)-primed, HIV-negative adults were administered two doses (30-days apart) of M72/AS01. Blood samples were collected pre-dose 1, pre-dose 2 and 1, 7, 10, 14, 17 and 30 days post-dose 2. RNA expression in blood and peripheral-blood mononuclear cells (PBMCs) was quantified using microarray technology. The data analysis used as a reference, a PBMC-gene signature that was associated with the protective efficacy of a similarly adjuvanted candidate malaria vaccine. Peripheral-blood CD4+ T-cell reactivity, serum interferon-gamma (IFNG) concentrations and safety were also assessed. Twenty subjects completed the study and 18 subjects received two doses. The observed safety profile was similar to previous trials. Serum IFNG responses and M72-specific CD4+ T cell responses to vaccination were detected as expected, based on previous trial experience. PBMC and whole-blood RNA-expression data at day 14 post-dose 2 relative to pre-vaccination and whole-blood RNA-expression data at 7, 10, and 17 days post-dose 2 relative to pre-vaccination could be used to classify vaccine recipients into gene-signature positive or gene-signature negative groups. In conclusion, whole blood sampled from the 7, 10, 14, or 17 day post-vaccination time points, in addition to pre-vaccination, could be selected to assess potentially clinically relevant responses to M72/AS01 using transcriptome analysis.
Adjuvant-Associated Peripheral Blood mRNA Profiles and Kinetics Induced by the Adjuvanted Recombinant Protein Candidate Tuberculosis Vaccine M72/AS01 in Bacillus Calmette-Guérin-Vaccinated Adults.
Specimen part, Subject
View SamplesThe goal of this study was to identify the transcriptional mechanisms involved in the activation of the immune system by QS-21, a triterpene glycoside purified from the bark of Quillaja saponaria which has adjuvant activity in vivo. Saponins represent a promising class of vaccine adjuvant. Together with the TLR4-ligand MPL, QS-21 is part of the Adjuvant System AS01, a key component of the Malaria and Zoster candidate vaccines that display demonstrated clinical efficacy. However, the mechanism of action of QS-21 in this liposomal formulation is poorly understood. Upon intra-muscular immunisation, we observed that QS-21 rapidly accumulated in CD169+ resident macrophages of the draining lymph node where it elicited a local innate immune response. Depletion of these cells abrogated QS-21-mediated innate cell recruitment to the lymph node, dendritic cell (DC) phenotypic maturation as well as the adjuvant effect on T cell and antibody responses to co-administered antigens. DCs rather than lymph node-resident macrophages were directly involved in T cell priming by QS-21 as revealed by the decrease in antigen-specific T cell response in Batf3/ mice. Further analysis showed that the adjuvant effect of QS-21 depended on the integration of Caspase-1 and MyD88 pathways, at least in part through the local release of HMGB1. Taken together, this work unravels the key role of lymph node sentinel macrophage in controlling the adjuvant effect of a molecule proven to improve vaccine response in humans
Central Role of CD169<sup>+</sup> Lymph Node Resident Macrophages in the Adjuvanticity of the QS-21 Component of AS01.
Specimen part
View SamplesAnalysis of the gene signature of OX40+ Tregs, in comparison to OX40- Tregs and Tconvs, freshly isolated from liver cirrhosis and tumor of chronic HCV patients.
Fatty acid metabolism complements glycolysis in the selective regulatory T cell expansion during tumor growth.
Specimen part
View SamplesWhole transcriptome analysis of circulating B cells from multiple sclerosis (MS) patients and healthy donors (HD).
Analysis of coding and non-coding transcriptome of peripheral B cells reveals an altered interferon response factor (IRF)-1 pathway in multiple sclerosis patients.
Specimen part, Disease
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A dichotomy of gene regulatory associations during the activated B-cell to plasmablast transition.
Specimen part, Cell line, Treatment
View SamplesThe activated B-cell (ABC) to plasmablast transition is the cusp of antibody secreting cell (ASC) differentiation but is incompletely defined. We apply expression time-courses, parsimonious gene correlation network analysis, and ChIP-seq to explore this in human cells. The transition initiates with input signal loss leading within hours from cell growth dominant programs to enhanced proliferation, accompanied from 24h by ER-stress response, secretory optimization and upregulation of ASC features. Clustering of genomic occupancy for ASC transcription factors (TFs) IRF4, BLIMP1 and XBP1 with CTCF and histone marks defines distinct patterns for each factor in plasmablasts. Integrating TF-associated clusters and modular gene expression identifies a dichotomy: XBP1 and IRF4 significantly link to gene modules induced in plasmablasts, but not to modules of repressed genes, while BLIMP1 links to modules of ABC genes repressed in plasmablasts but is not significantly associated with modules induced in plasmablasts. Pharmacological inhibition of the G9A (EHMT2) histone-methytransferase, a BLIMP1 co-factor that catalyzes repressive H3K9me2 marks, leaves functional ASC differentiation intact but de-represses ABC-state genes. Thus, in human plasmablasts IRF4 and XBP1 emerge as the dominant association with ASC gene expression, while BLIMP1 links to repressed modules with particular focus in repression of the B-cell activation state.
A dichotomy of gene regulatory associations during the activated B-cell to plasmablast transition.
Specimen part
View Samples