Similar Datasets
Project description:Acute myeloid leukemia (AML) is a heterogeneous disease caused by recurrent mutations in the transcription regulatory machinery. As a result, malignant myeloid cells display abnormal growth and are blocked in differentiation. One type of recurrent mutations affects RUNX1 which is subject to mutations and translocations, the latter giving rise to fusion proteins with aberrant transcriptional activities. We recently compared the mechanism by which the products of the t(8;21) and the t(3;21) translocation RUNX1-ETO and RUNX1-EVI1 globally reprogram the epigenome. We demonstrated that a main component of the block in differentiation in both types of AML is direct repression of the gene encoding for the crucial myeloid regulator C/EBPα by both fusion proteins. We also showed that CEBPA upregulation is required for the release of the differentiation block after oncogene knock-down. In the study presented here we examined at the global level the response of t(8;21) and t(3;21) cells to C/EBPα overexpression. We show that C/EBPα overexpression does not change oncoprotein expression or globally displace these proteins from their binding sites, but up-regulates a core set of common target genes important for myeloid differentiation and interferes with leukemic growth, highlighting CEBPA regulated pathways as targets for therapeutic intervention.
2018-04-30 | GSE102730 | GEO
Project description:Acute myeloid leukemia (AML) is a heterogeneous disease caused by recurrent mutations in the transcription regulatory machinery. As a result, malignant myeloid cells display abnormal growth and are blocked in differentiation. One type of recurrent mutations affects RUNX1 which is subject to mutations and translocations, the latter giving rise to fusion proteins with aberrant transcriptional activities. We recently compared the mechanism by which the products of the t(8;21) and the t(3;21) translocation RUNX1-ETO and RUNX1-EVI1 globally reprogram the epigenome. We demonstrated that a main component of the block in differentiation in both types of AML is direct repression of the gene encoding for the crucial myeloid regulator C/EBPα by both fusion proteins. We also showed that CEBPA upregulation is required for the release of the differentiation block after oncogene knock-down. In the study presented here we examined at the global level the response of t(8;21) and t(3;21) cells to C/EBPα overexpression. We show that C/EBPα overexpression does not change oncoprotein expression or globally displace these proteins from their binding sites, but up-regulates a core set of common target genes important for myeloid differentiation and interferes with leukemic growth, highlighting CEBPA regulated pathways as targets for therapeutic intervention.
2018-04-30 | GSE102697 | GEO
Project description:C/EBPα overexpression overrides epigenetic reprogramming by RUNX1-ETO and RUNX1-EVI1
| PRJNA398540 | ENA
Project description:Acute myeloid leukemia (AML) is a heterogeneous disease caused by mutations in transcriptional regulator genes, but how different mutant regulators shape the chromatin landscape is unclear. Here, we compared the transcriptional networks of two types of AML with chromosomal translocations of the RUNX1 locus that fuse the RUNX1 DNA-binding domain to different regulators, the t(8;21) expressing RUNX1-ETO and the t(3;21) expressing RUNX1-EVI1. Despite containing the same DNA-binding domain, the two fusion proteins display distinct binding patterns, show differences in gene expression and chromatin landscape, and are dependent on different transcription factors. RUNX1-EVI1 directs a stem cell-like transcriptional network reliant on GATA2, whereas that of RUNX1-ETO-expressing cells is more mature and depends on RUNX1. However, both types of AML are dependent on the continuous expression of the fusion proteins. Our data provide a molecular explanation for the differences in clinical prognosis for these types of AML.
| S-EPMC5457485 | biostudies-literature
Project description:RUNX1/ETO (RE), the t(8;21)-derived leukemic transcription factor associated with acute myeloid leukemia (AML) development, deregulates genes involved in differentiation, self-renewal and proliferation. In addition, these cells show differences in cellular adhesion behavior whose molecular basis is not well understood. Here, we demonstrate that RE epigenetically silences the gene encoding P-Selectin Glycoprotein Ligand-1 (PSGL-1) and downregulates PSGL-1 expression in human CD34+ and murine lin- hematopoietic progenitor cells. Levels of PSGL-1 inversely and dose-dependently correlate with RE oncogene levels. However, a DNA-binding defective mutant fails to downregulate PSGL-1. We show by ChIP experiments that the PSGL-1 promoter is a direct target of RE and binding is accompanied by high levels of the repressive chromatin mark histone H3K27me3. In t(8;21)+ Kasumi-1 cells, PSGL-1 expression is completely restored at both the mRNA and cell surface protein levels following RE downregulation with short hairpin RNA (shRNA) or RE inhibition with tetramerization-blocking peptides, and at the promoter H3K27me3 is replaced by the activating chromatin mark H3K9ac as well as by RNA polymerase II. Upregulation of PSGL-1 restores the binding of cells to P- and E-selectin and re-establishes myeloid-specific cellular adhesion while it fails to bind to lymphocyte-specific L-selectin. Overall, our data suggest that the RE oncoprotein epigenetically represses PSGL-1 via binding to its promoter region and thus affects the adhesive behavior of t(8;21)+ AML cells.
| S-EPMC5399174 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below.
2015-08-26 | GSE64625 | GEO
Project description:Acute myeloid leukemia (AML) is associated with mutations in transcriptional and epigenetic regulator genes impairing myeloid differentiation. The t(8;21)(q22;q22) translocation generates the RUNX1-ETO fusion protein, which interferes with the hematopoietic master regulator RUNX1. We previously showed that the maintenance of t(8;21) AML is dependent on RUNX1-ETO expression. Its depletion causes extensive changes in transcription factor binding, as well as gene expression, and initiates myeloid differentiation. However, how these processes are connected within a gene regulatory network is unclear. To address this question, we performed Promoter-Capture Hi-C assays, with or without RUNX1-ETO depletion and assigned interacting cis-regulatory elements to their respective genes. To construct a RUNX1-ETO-dependent gene regulatory network maintaining AML, we integrated cis-regulatory element interactions with gene expression and transcription factor binding data. This analysis shows that RUNX1-ETO participates in cis-regulatory element interactions. However, differential interactions following RUNX1-ETO depletion are driven by alterations in the binding of RUNX1-ETO-regulated transcription factors.
| S-EPMC6899442 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below.
2020-04-17 | GSE143460 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below.
2024-05-06 | GSE247095 | GEO
Project description:Acute myeloid leukemia (AML) is a heterogeneous disease caused by recurrent mutations in the transcription regulatory machinery, resulting in abnormal growth and a block in differentiation. One type of recurrent mutations affects RUNX1, which is subject to mutations and translocations, the latter giving rise to fusion proteins with aberrant transcriptional activities. We recently compared the mechanism by which the products of the t(8;21) and the t(3;21) translocation RUNX1-ETO and RUNX1-EVI1 reprogram the epigenome. We demonstrated that a main component of the block in differentiation in both types of AML is direct repression of the gene encoding the myeloid regulator C/EBP? by both fusion proteins. Here, we examined at the global level whether C/EBP? is able to reverse aberrant chromatin programming in t(8;21) and t(3;21) AML. C/EBP? overexpression does not change oncoprotein expression or globally displace these proteins from their binding sites. Instead, it upregulates a core set of common target genes important for myeloid differentiation and represses genes regulating leukemia maintenance. This study, therefore, identifies common CEBPA-regulated pathways as targets for therapeutic intervention.
| S-EPMC5812331 | biostudies-literature