TMD AMKL targeted follow up part 2
Ontology highlight
ABSTRACT:
PROVIDER: EGAS00001000732 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:Genomic libraries will be generated from total genomic DNA derived from 200+ patients with childhood Transient Myeloproliferative Disorder (TMD) and or Acute Megakaryocytic Leukemia (AMKL) as well some matched constitutional samples (n < 50). Libraries will be enriched for a selected panel of genes using a bespoke pulldown protocol. 96 Samples will be individually barcoded and subjected to up to two lanes of Illumina HiSeq. Paired reads will be mapped to build 37 of the human reference genome to facilitate the characterisation of known gene mutations in cancer as well as the validation of potentially novel variants identified by prior exome sequencing.
| EGAS00001000569 | EGA
Project description:Down syndrome (DS), with trisomy of chromosome 21 (HSA21), is the commonest human aneuploidy. Pre-leukemic myeloproliferative changes in DS fetal livers precedes the acquisition of GATA1 mutations, transient myeloproliferative disorder (DS-TMD) and acute megakaryocytic leukemia (DS-AMKL). Trisomy of the Erg gene is required for myeloproliferation in the Ts(1716)65Dn DS mouse model. We demonstrate here that genetic changes due trisomy of Erg lead to lineage priming of primitive and early multipotential progenitor cells in Ts(1716)65Dn mice, excess megakaryocyte-erythroid progenitors, and malignant myeloproliferation. Correlation of gene expression changes caused by Erg trisomy in Ts(1716)65Dn multilineage progenitor cells with those associated with trisomy 21 in human DS HSCs support a role for ERG as a regulator of hematopoietic lineage potential, trisomy of which drives pre-leukemic changes in DS fetal livers that predispose to subsequent DS-TMD and DS-AMKL.
2015-04-15 | E-MTAB-2574 | biostudies-arrayexpress
Project description:Genomic libraries will be generated from total genomic DNA derived from 200+ patients with childhood Transient Myeloproliferative Disorder (TMD) and or Acute Megakaryocytic Leukemia (AMKL) as well some matched constitutional samples (n < 50). Libraries will be enriched for a selected panel of genes using a bespoke pulldown protocol. 96 Samples will be individually barcoded and subjected to up to two lanes of Illumina HiSeq. Paired reads will be mapped to build 37 of the human reference genome to facilitate the characterisation of known gene mutations in cancer as well as the validation of potentially novel variants identified by prior exome sequencing.
| EGAD00001000879 | EGA
Project description:Genomic libraries will be generated from total
genomic DNA derived from 200+ patients with childhood Transient
Myeloproliferative Disorder (TMD) and or Acute Megakaryocytic
Leukemia (AMKL) as well some matched constitutional samples (n <
50 ). Libraries will be enriched for a selected panel of genes using a bespoke pulldown protocol. 96 Samples will be individually barcoded and subjected to up to two lanes of Illumina HiSeq. Paired reads will be mapped to build 37 of the human reference genome to facilitate the characterisation of known gene mutations in cancer as well as the validation of potentially novel variants identified by prior exome sequencing.
| EGAD00001000783 | EGA
Project description:Background: Children with Down syndrome (DS) are predisposed to acute megakaryoblastic leukemia (AMKL, or AML M7) and a related myeloid disorder, referred to as transient myeloproliferative disorder (TMD), or transient leukemia (TL). Recently, acquired mutations in the erythroid/megakaryocytic lineage-specific transcription factor GATA-1 have been identified in megakaryoblasts from virtually all DS patients with AMKL (DS-AMKL), as well as in nearly all DS neonates with TMD. These mutations prevent synthesis of full-length GATA-1, but lead to synthesis of a truncated GATA-1 protein (GATA-1s) that lacks the N-terminal transactivation domain. To determine the in vivo requirement of GATA-1 N-terminal domain in hematopoiesis and to model DS megakaryocytic leukemia initiated by GATA-1 mutation, we generated a GATA-1 knockin allele with a truncation at this domain (GATA-1deltaN). ES cells bearing this mutant allele generated a unique type of large Thrombopoietin (Tpo)-dependent megakaryocytes-containing colonies, when differentiated in vitro. Fetal livers from mice carrying this mutant allele contained elevated numbers of CD41+ cells throughout embryonic development, especially during mid-gestation. In in vitro hematopoietic colony assays, mutant cells from yolk sacs and mid-gestation fetal livers gave rise to a large number of macroscopic hyperproliferative megakaryocytic colonies (CFU-MKs). Consistent with that, when mutant fetal liver progenitors were cultured in liquid medium in the presence of Tpo, the derived megakaryocytes displayed marked hyperproliferation and grew for longer period of time than WTs. Specific aims: To understand the molecular basis for the megakaryocytic hyperproliferation phenotype of the GATA-1deltaN mutants, we plan to profile gene expression patterns of fetal liver-derived primary megakaryocytes and megakaryocytic progenitors from the GATA-1deltaN mutants and compare them with WTs, as well as GATA-1deltaNeodeltaHS mutants (GATA-1megakaryocytes). Experimental design: E12.5 fetal livers were harvested from either GATA-1 WT and mutant embryos. Single cell suspensions were made from these livers and the cells were cultured in liquid medium in the presence of Tpo for 3 days. On day 3, primary megakaryocytes were enriched by a BSA gradient, and further enriched by anti-CD41 antibody and magnetic microbeads. Megakaryocytic progenitors were collected by FACS sorting for small cells in the same culture that express low level of CD41. Total RNAs were then prepared from these two populations and submitted for microarray profiling. Conclusions: When examining genes that are normally upregulated upon megakaryocyte differentiation (many of this class are megakaryocyte-specific genes), we found in GATA-1deltaN megakaryocytes, the majority of these genes are upregulated, although not to the full extent as seen in WTs. In contrast, this class of genes is largely not upregulated in GATA-1deltaNeodeltaHS megakaryocytes, which are blocked at an immature stage of differentiation. Genes that are downregulated during megakaryocyte differentiation include those that are normally repressed by GATA-1. Among genes that are not properly downregulated in GATA-1deltaN megakaryocytes, five transcription factors (Myc, Myb, GATA-2, PU.1, Ikaros) are of particular interest. Inadequate GATA-1s-mediated repression of transcription factors required for proliferation of hematopoietic progenitors (Myc, Myb and GATA-2) and for specifying lineage choices other than megakaryocyte/erythrocyte (PU.1 and Ikaros) may contribute to hyperproliferation of GATA-1deltaN megakaryocytes.
2007-08-31 | E-GEOD-2433 | biostudies-arrayexpress
Project description:Acute megakaryoblastic leukemia (AMKL) is more frequently seen in Down syndrome patients, where it is often preceded by a transient myeloproliferative disorder (DS-TMD). The development of DS-TMD and DS-AMKL require not only the presence of the trisomy 21 but also that of GATA1 mutations. However, despite extensive studies into the genetics of DS-AMKL, not much is known about the epigenetic deregulation associated with this disease. In order to understand how epigenetic changes at the DNA methylation level contribute to DS leukemogenesis we performed DNA methylation profiling at different stages of development of this disease and analyzed the dynamics of epigenetic reprogramming. Early genome-wide epigenetic changes can be detected in trisomy 21 fetal liver mononuclear cells, even prior to the development of hematological abnormalities. These early changes are characterized by marked loss of DNA methylation at genes associated with regulation of key developmental processes. This first wave of aberrant DNA hypomethylation is followed by a second wave of epigenetic reprogramming detected in blast cells from DS-TMD and DS-AMKL, characterized by gains of methylation. This second wave of hypermethylation targets a distinct set of genes, preferentially affecting genes involved in hematopoiesis and regulation of cell growth and proliferation. DNA methylation profiles obtained at different stages of the development of Down syndrome AMKL and from CD41+ cells from partial trisomic mice
2013-08-19 | E-GEOD-46167 | biostudies-arrayexpress
Project description:Acute megakaryoblastic leukemia (AMKL) is more frequently seen in Down syndrome patients, where it is often preceded by a transient myeloproliferative disorder (DS-TMD). The development of DS-TMD and DS-AMKL require not only the presence of the trisomy 21 but also that of GATA1 mutations. However, despite extensive studies into the genetics of DS-AMKL, not much is known about the epigenetic deregulation associated with this disease. In order to understand how epigenetic changes at the DNA methylation level contribute to DS leukemogenesis we performed DNA methylation profiling at different stages of development of this disease and analyzed the dynamics of epigenetic reprogramming. Early genome-wide epigenetic changes can be detected in trisomy 21 fetal liver mononuclear cells, even prior to the development of hematological abnormalities. These early changes are characterized by marked loss of DNA methylation at genes associated with regulation of key developmental processes. This first wave of aberrant DNA hypomethylation is followed by a second wave of epigenetic reprogramming detected in blast cells from DS-TMD and DS-AMKL, characterized by gains of methylation. This second wave of hypermethylation targets a distinct set of genes, preferentially affecting genes involved in hematopoiesis and regulation of cell growth and proliferation.
2013-08-19 | GSE46167 | GEO
Project description:DS children have a 500-fold increased risk for developing acute megakaryoblastic leukemia (AMKL). Around 10% of DS newborns have a transient myeloproliferative disorder (TMD) that resolves spontaneously. Somatic mutations acquired during fetal hematopoiesis in the GATA1 transcription factor are detected in megakaryoblasts from all the DS TMDs or AMKLs. GATA1 is an X chromosome transcription factor essential for the development of multiple hematopoietic lineages. Loss of GATA1 results in embryonic lethality due to severe anemia. The GATA1 mutations result in the expression of a shorter isoform, GATA1s. Replacement of GATA1 with GATA1s causes transient proliferation of immature fetal megakaryocytic progenitors. The Hsa21 ETS transcription factor, ERG, is expressed in megakaryocytes and erythrocytes and is involved in several types of cancer. Mutation in GATA1 gene leading to expression of the short isoform (GATA1s) that occurs on the background of trisomy 21 is regarded as one of the driving forces for megakaryocytic expansion observed in DS fetal livers. ERG, which is located on chromosome 21, is considered one of the leading candidates to cooperate with GATA1 mutation in the generation of DS AMKL. To study the in vivo cooperation between ERG and GATA1 isoforms, we crossed the ERG transgenic mice with the GATA1s Knock-in mice (GATA null background). We found that males expressing both ERG and the short isoform of GATA1(GATA1s) died in uterus between embryonic days E121/2 and E141/2.We studied erythropoiesis and megakaryopoiesis in fetal livers from the different genotypes generated from our cross. We used expression array to study the specific interaction of ERG with the different GATA1 isoforms in fetal livers from E121/2 and E141/2 and identify ERG, GATA1 and GATA1s target genes by comparing sets of genes that are activated or repressed in the presence of ERG and the two isoforms of GATA1.
2013-12-31 | E-GEOD-46481 | biostudies-arrayexpress
Project description:Background: Children with Down syndrome (DS) are predisposed to acute megakaryoblastic leukemia (AMKL, or AML M7) and a related myeloid disorder, referred to as transient myeloproliferative disorder (TMD), or transient leukemia (TL). Recently, acquired mutations in the erythroid/megakaryocytic lineage-specific transcription factor GATA-1 have been identified in megakaryoblasts from virtually all DS patients with AMKL (DS-AMKL), as well as in nearly all DS neonates with TMD. These mutations prevent synthesis of full-length GATA-1, but lead to synthesis of a truncated GATA-1 protein (GATA-1s) that lacks the N-terminal transactivation domain. To determine the in vivo requirement of GATA-1 N-terminal domain in hematopoiesis and to model DS megakaryocytic leukemia initiated by GATA-1 mutation, we generated a GATA-1 knockin allele with a truncation at this domain (GATA-1deltaN). ES cells bearing this mutant allele generated a unique type of large Thrombopoietin (Tpo)-dependent megakaryocytes-containing colonies, when differentiated in vitro. Fetal livers from mice carrying this mutant allele contained elevated numbers of CD41+ cells throughout embryonic development, especially during mid-gestation. In in vitro hematopoietic colony assays, mutant cells from yolk sacs and mid-gestation fetal livers gave rise to a large number of macroscopic hyperproliferative megakaryocytic colonies (CFU-MKs). Consistent with that, when mutant fetal liver progenitors were cultured in liquid medium in the presence of Tpo, the derived megakaryocytes displayed marked hyperproliferation and grew for longer period of time than WTs. Specific aims: To understand the molecular basis for the megakaryocytic hyperproliferation phenotype of the GATA-1deltaN mutants, we plan to profile gene expression patterns of fetal liver-derived primary megakaryocytes and megakaryocytic progenitors from the GATA-1deltaN mutants and compare them with WTs, as well as GATA-1deltaNeodeltaHS mutants (GATA-1– megakaryocytes). Experimental design: E12.5 fetal livers were harvested from either GATA-1 WT and mutant embryos. Single cell suspensions were made from these livers and the cells were cultured in liquid medium in the presence of Tpo for 3 days. On day 3, primary megakaryocytes were enriched by a BSA gradient, and further enriched by anti-CD41 antibody and magnetic microbeads. Megakaryocytic progenitors were collected by FACS sorting for small cells in the same culture that express low level of CD41. Total RNAs were then prepared from these two populations and submitted for microarray profiling. Conclusions: When examining genes that are normally upregulated upon megakaryocyte differentiation (many of this class are megakaryocyte-specific genes), we found in GATA-1deltaN megakaryocytes, the majority of these genes are upregulated, although not to the full extent as seen in WTs. In contrast, this class of genes is largely not upregulated in GATA-1deltaNeodeltaHS megakaryocytes, which are blocked at an immature stage of differentiation. Genes that are downregulated during megakaryocyte differentiation include those that are normally repressed by GATA-1. Among genes that are not properly downregulated in GATA-1deltaN megakaryocytes, five transcription factors (Myc, Myb, GATA-2, PU.1, Ikaros) are of particular interest. Inadequate GATA-1s-mediated repression of transcription factors required for proliferation of hematopoietic progenitors (Myc, Myb and GATA-2) and for specifying lineage choices other than megakaryocyte/erythrocyte (PU.1 and Ikaros) may contribute to hyperproliferation of GATA-1deltaN megakaryocytes. Keywords = GATA-1 Keywords = megakaryocyte Keywords = mouse model Keywords: other
2005-05-14 | GSE2433 | GEO
Project description:DS children have a 500-fold increased risk for developing acute megakaryoblastic leukemia (AMKL). Around 10% of DS newborns have a transient myeloproliferative disorder (TMD) that resolves spontaneously. Somatic mutations acquired during fetal hematopoiesis in the GATA1 transcription factor are detected in megakaryoblasts from all the DS TMDs or AMKLs. GATA1 is an X chromosome transcription factor essential for the development of multiple hematopoietic lineages. Loss of GATA1 results in embryonic lethality due to severe anemia. The GATA1 mutations result in the expression of a shorter isoform, GATA1s. Replacement of GATA1 with GATA1s causes transient proliferation of immature fetal megakaryocytic progenitors. The Hsa21 ETS transcription factor, ERG, is expressed in megakaryocytes and erythrocytes and is involved in several types of cancer. Mutation in GATA1 gene leading to expression of the short isoform (GATA1s) that occurs on the background of trisomy 21 is regarded as one of the driving forces for megakaryocytic expansion observed in DS fetal livers. ERG, which is located on chromosome 21, is considered one of the leading candidates to cooperate with GATA1 mutation in the generation of DS AMKL. To study the in vivo cooperation between ERG and GATA1 isoforms, we crossed the ERG transgenic mice with the GATA1s Knock-in mice (GATA null background). We found that males expressing both ERG and the short isoform of GATA1(GATA1s) died in uterus between embryonic days E121/2 and E141/2.We studied erythropoiesis and megakaryopoiesis in fetal livers from the different genotypes generated from our cross.
2013-12-31 | GSE46481 | GEO