Recently global gene expression profiling of patients samples lead to a molecular definition of Burkitt Lymphoma (BL) with lymphocyte enhancer-binding factor 1 (LEF1) as a signature gene. Here we report the discovery of nucleic LEF1 in a very high proportion of BL cases (15/18) and LEF1 target genes. Germinal center B cells were devoid of detectable nuclear LEF1 expression as mantle cell lymphoma (0/5), marginal zone lymphoma (0/6), follicular lymphoma (0/12) or diffuse large B cell lymphoma (DLBCL) (1/31). Using whole genome gene expression profiling after transient knockdown of LEF1 in BL cell lines, new LEF1 target genes were identified. The joint expression of these genes in primary BL samples shows that LEF1 is not only expressed aberrantly in BL but also transcriptionally active. Our study identified aberrantly expressed LEF1 and its target genes suggesting an important functional role in BLs.
Aberrant lymphocyte enhancer-binding factor 1 expression is characteristic for sporadic Burkitt's lymphoma.
Cell line
View SamplesExpression data of BL2 Burkitt Lymphoma cell line (controls and samples treated with different B cell specific stimuli)
Global gene expression changes of in vitro stimulated human transformed germinal centre B cells as surrogate for oncogenic pathway activation in individual aggressive B cell lymphomas.
Specimen part, Cell line
View SamplesThe identification of small molecules which either increase the number and/or enhance the activity of CD34+ hematopoietic stem and progenitor cells (HSPCs) during ex-vivo expansion has remained challenging. Applying an unbiased in vivo chemical screen in a transgenic (c-myb:EGFP) zebrafish embryo model, histone deacetylase inhibitors (HDACI) (valproic acid, resminostat and entinostat) were shown to significantly amplify the number of phenotypic hematopoietic precursors. The identified HDACIs were confirmed to significantly enhance also the expansion of human HSPCs during ex vivo treatment. Long-term functionality of ex vivo expanded human HSPCs was verified in a xenotransplantation model using NSG mice. However, the HDACI induced proliferation of HSPCs was associated with short-term functional changes. One of the identified hits, valproic acid (VPA), increased the adhesion capacity of CD34+ cells on primary mesenchymal stromal cells and reduced their chemokine-mediated migration capacity in vitro. In line with the reduced migratory potential in vitro, homing as well as early engraftment of VPA treated human CD34+ cells was significantly impaired in the xenotransplantation model. Our data confirms that HDACI treatment leads to a net expansion of HSPCs cells with long-term engraftment potential across different species. However impaired homing and short-term-engraftment has to be kept in mind when designing clinical transplantation protocols. In addition, our gene expression analysis (RNA-Seq) revealed expression of several genes that were altered in CD34+ cells by VPA treatment including cell adhesion molecules and Notch and wnt genes which has been shown to be involved in preservation of stem cell properties. Overall design: Gene expression analysis of in vitro expanded human HSPCs (CD34+ cells) by valproic acid
Zebrafish In-Vivo Screening for Compounds Amplifying Hematopoietic Stem and Progenitor Cells: - Preclinical Validation in Human CD34+ Stem and Progenitor Cells.
Disease, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Identification of a new gene regulatory circuit involving B cell receptor activated signaling using a combined analysis of experimental, clinical and global gene expression data.
Specimen part, Cell line, Treatment, Time
View SamplesTo discover new essential regulatory pathways in B lymphoma cells a combined analysis of experimental and clinical high throughput data was performed. Among others, a specific cluster of coherently expressed genes named BCR.1 was identified in primary lymphoma samples. These coherently expressed genes are suppressed by -IgM treatment of lymphoma cells in vitro. This B cell receptor activation leads to a G2 phase prolongation, delayed entry into the M phase, an overall diminished capacity of the cells to enter into mitosis and defects in metaphases. Cytogenetic changes are detected under long term -IgM treatment. Furthermore, an inverse correlation of BCR.1 genes with c-Myc coregulated genes in distinct groups of lymphoma patients is observed. In addition to the impact of c-Myc in the regulation of cell cycle regulators, BCR.1 genes are regulated by a combined action of IKK2, MAPK14 and JNK. Finally, the BCR.1 index discriminates activated B cell like and germinal centre B cell like diffuse large B cell lymphoma. Therefore, a new regulatory circuit is described affecting cell cycle and chromosome instability in B cells.
Identification of a new gene regulatory circuit involving B cell receptor activated signaling using a combined analysis of experimental, clinical and global gene expression data.
Specimen part, Time
View SamplesTo discover new essential regulatory pathways in B lymphoma cells a combined analysis of experimental and clinical high throughput data was performed. Among others, a specific cluster of coherently expressed genes named BCR.1 was identified in primary lymphoma samples. These coherently expressed genes are suppressed by -IgM treatement of lymphoma cells in vitro. This B cell receptor activation leads to a G2 phase prolongation, delayed entry into the M phase, an overall diminished capacity of the cells to enter into mitosis and defects in metaphases. Cytogenetic changes are detected under long term -IgM treatment. Furthermore, an inverse correlation of BCR.1 genes with c-Myc coregulated genes in distinct groups of lymphoma patients is observed. In addition to the impact of c-Myc in the regulation of cell cycle regulators, BCR.1 genes are regulated by a combined action of IKK2, MAPK14 and JNK. Finally, the BCR.1 index discriminates activated B cell like and germinal centre B cell like diffuse large B cell lymphoma. Therefore, a new regulatory circuit is described affecting cell cycle and chromosome instability in B cells.
Identification of a new gene regulatory circuit involving B cell receptor activated signaling using a combined analysis of experimental, clinical and global gene expression data.
Specimen part
View SamplesDiagnostic samples of peripheral blood form acute myeloid leukemia were analysed for gene expression differences
NFATc1 as a therapeutic target in FLT3-ITD-positive AML.
Sex, Specimen part
View SamplesThe Loeys-Dietz syndrome (LDS) is an inherited connective tissue disorder caused by mutations in the transforming growth factor (TGF-) receptors TGFBR1 or TGFBR2. Most patients with LDS develop severe aortic aneurysms resulting in early need of surgical intervention. We investigated circulating outgrowth endothelial cells (OEC) from the peripheral blood of LDS to gain further insight into the pathophysiology of the disorder. We performed gene expression profiling using microarray analysis followed by quantitative PCR for verification of gene expression. OECs isolated from age- and sex-matched healthy donors served as reference control.
Overexpression of Gremlin-1 in patients with Loeys-Dietz syndrome: implications on pathophysiology and early disease detection.
Sex, Age, Specimen part, Disease
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Systems biology of the IMIDIA biobank from organ donors and pancreatectomised patients defines a novel transcriptomic signature of islets from individuals with type 2 diabetes.
Age
View SamplesPancreatic islet beta cell failure causes type 2 diabetes (T2D). The IMIDIA consortium has used a strategy entailing a stringent comparative transcriptomics analysis of islets isolated enzymatically or by laser microdissection from two large cohorts of non-diabetic (ND) and T2D organ donors (OD) or partially pancreatectomized patients (PPP). This work led to the identification of a signature of genes that were differentially expressed between T2D and ND regardless of the sample type (OD or PPP). This signature includes 19 genes, of which 9 have never been previously reported to be differentially expressed in T2D islets. The PPP cohort also includes samples from individuals with impaired glucose tolerance (IGT) or recent onset diabetes associated with a pancreatic exocrine disorder (T3cD). Notably, none of the 19 signature genes of T2D islets were significantly dysregulated in islets of subjects with IGT or T3cD, suggesting that their changed expression reflects beta cell deterioration rather than a deficit preceding it.
Systems biology of the IMIDIA biobank from organ donors and pancreatectomised patients defines a novel transcriptomic signature of islets from individuals with type 2 diabetes.
Age
View Samples