The histone demethylase KDM1A sustains the oncogenic potential of MLL-AF9 leukemia stem cells
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ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE36348 | GEO | 2012/03/29
SECONDARY ACCESSION(S): PRJNA153305
REPOSITORIES: GEO
Similar Datasets
Project description:This SuperSeries is composed of the following subset Series: GSE36346: The histone demethylase KDM1A sustains the oncogenic potential of MLL-AF9 leukemia stem cells (ChIP-Seq data) GSE36347: The histone demethylase KDM1A sustains the oncogenic potential of MLL-AF9 leukemia stem cells (expression data) Refer to individual Series
2012-03-28 | E-GEOD-36348 | biostudies-arrayexpress
Project description:Using a mouse model of human MLL-AF9 leukemia, we identified the lysine-specific demethylase KDM1A (LSD1 or AOF2) as an essential regulator of leukemia stem cell (LSC) potential. KDM1A acts at genomic loci bound by MLL-AF9 to sustain expression of the associated oncogenic program, thus preventing differentiation and apoptosis. In vitro and in vivo pharmacologic targeting of KDM1A using tranylcypromine analogues active in the nanomolar range phenocopied Kdm1a knockdown in both murine and primary human AML cells exhibiting MLL translocations. By contrast, the clonogenic and repopulating potential of normal hematopoietic stem and progenitor cells was spared. Our data establish KDM1A as a key effector of the differentiation block in MLL leukemia which may be selectively targeted to therapeutic effect. To investigate the genetic program regulated by KDM1A in murine MLL-AF9 AML cells enriched for LSCs, we compared the transcriptome of KIT+Gr1+ control and Kdm1a KD cells using exon arrays soon after initiation of KD. At this time, there was no immunophenotypic evidence of differentiation in Kdm1a KD cells. Exonic expression values were condensed into gene-level expression summaries, which represent the mean expression value of the probe sets targeting the length of a given protein coding gene. Three separate samples from two different animals were used. Kdm1a KD samples were compared with control samples. Total six arrays.
2012-03-28 | E-GEOD-36347 | biostudies-arrayexpress
Project description:Using a mouse model of human MLL-AF9 leukemia, we identified the lysine-specific demethylase KDM1A (LSD1 or AOF2) as an essential regulator of leukemia stem cell (LSC) potential. KDM1A acts at genomic loci bound by MLL-AF9 to sustain expression of the associated oncogenic program, thus preventing differentiation and apoptosis. In vitro and in vivo pharmacologic targeting of KDM1A using tranylcypromine analogues active in the nanomolar range phenocopied Kdm1a knockdown in both murine and primary human AML cells exhibiting MLL translocations. By contrast, the clonogenic and repopulating potential of normal hematopoietic stem and progenitor cells was spared. Our data establish KDM1A as a key effector of the differentiation block in MLL leukemia which may be selectively targeted to therapeutic effect. To investigate the effects of Kdm1a KD on histone modifications, we performed chromatin immunoprecipitation followed by next-generation sequencing (ChIP-Seq) in control and Kdm1a KD MLL-AF9 AML cells for dimethyl-H3K4 and dimethyl-H3K9, as well as for trimethyl-H3K4 and trimethyl-H3K9. Dimethyl-H3K4 and dimethyl-H3K9 are targeted for demethylation by KDM1A. For each of these histone modifications, we compared the mean ChIP-Seq signal across and around protein coding genes bound by the MLL-AF9 oncoprotein (Bernt et al., 2011) with the mean signal from genes not bound by MLL-AF9 expressed at high, middle or low levels.
2012-03-28 | E-GEOD-36346 | biostudies-arrayexpress
Project description:Using a mouse model of human MLL-AF9 leukemia, we identified the lysine-specific demethylase KDM1A (LSD1 or AOF2) as an essential regulator of leukemia stem cell (LSC) potential. KDM1A acts at genomic loci bound by MLL-AF9 to sustain expression of the associated oncogenic program, thus preventing differentiation and apoptosis. In vitro and in vivo pharmacologic targeting of KDM1A using tranylcypromine analogues active in the nanomolar range phenocopied Kdm1a knockdown in both murine and primary human AML cells exhibiting MLL translocations. By contrast, the clonogenic and repopulating potential of normal hematopoietic stem and progenitor cells was spared. Our data establish KDM1A as a key effector of the differentiation block in MLL leukemia which may be selectively targeted to therapeutic effect. To investigate the genetic program regulated by KDM1A in murine MLL-AF9 AML cells enriched for LSCs, we compared the transcriptome of KIT+Gr1+ control and Kdm1a KD cells using exon arrays soon after initiation of KD. At this time, there was no immunophenotypic evidence of differentiation in Kdm1a KD cells. Exonic expression values were condensed into gene-level expression summaries, which represent the mean expression value of the probe sets targeting the length of a given protein coding gene.
2012-03-29 | GSE36347 | GEO
Project description:Using a mouse model of human MLL-AF9 leukemia, we identified the lysine-specific demethylase KDM1A (LSD1 or AOF2) as an essential regulator of leukemia stem cell (LSC) potential. KDM1A acts at genomic loci bound by MLL-AF9 to sustain expression of the associated oncogenic program, thus preventing differentiation and apoptosis. In vitro and in vivo pharmacologic targeting of KDM1A using tranylcypromine analogues active in the nanomolar range phenocopied Kdm1a knockdown in both murine and primary human AML cells exhibiting MLL translocations. By contrast, the clonogenic and repopulating potential of normal hematopoietic stem and progenitor cells was spared. Our data establish KDM1A as a key effector of the differentiation block in MLL leukemia which may be selectively targeted to therapeutic effect.
2012-03-29 | GSE36346 | GEO
Project description:The 'Yamanaka factors' (Oct4, Sox2, Klf4 and c-Myc) are able to generate induced pluripotent stem (iPS) cells from different cell types. However, to what degree primary malignant cells can be reprogrammed into a pluripotent state has not been vigorously assessed. We established an acute myeloid leukemia (AML) model by overexpressing the human mixed-lineage leukemia-AF9 (MLL-AF9) fusion gene in mouse hematopoietic cells that carry Yamanaka factors under the control of doxycycline (Dox). On addition of Dox to the culture, the transplantable leukemia cells were efficiently converted into iPS cells that could form teratomas and produce chimeras. Interestingly, most chimeric mice spontaneously developed the same type of AML. Moreover, both iPS reprogramming and leukemia reinitiation paths could descend from the same leukemia-initiating cell. RNA-seq analysis showed reversible global gene expression patterns between these interchangeable leukemia and iPS cells on activation or reactivation of MLL-AF9, suggesting a sufficient epigenetic force in driving the leukemogenic process. This study represents an important step for further defining the potential interplay between oncogenic molecules and reprogramming factors during MLL leukemogenesis. More importantly, our reprogramming approach may be expanded to characterize a range of hematopoietic malignancies in order to develop new strategies for clinical diagnosis and treatment.
| S-EPMC4017259 | biostudies-literature
Project description:Self-renewal is a hallmark of both hematopoietic stem cells (HSCs) and leukemia stem cells (LSCs); therefore, the identification of mechanisms that are required for LSC, but not HSC, function could provide therapeutic opportunities that are more effective and less toxic than current treatments. Here, we employed an in vivo shRNA screen and identified jumonji domain-containing protein JMJD1C as an important driver of MLL-AF9 leukemia. Using a conditional mouse model, we showed that loss of JMJD1C substantially decreased LSC frequency and caused differentiation of MLL-AF9- and homeobox A9-driven (HOXA9-driven) leukemias. We determined that JMJD1C directly interacts with HOXA9 and modulates a HOXA9-controlled gene-expression program. In contrast, loss of JMJD1C led to only minor defects in blood homeostasis and modest effects on HSC self-renewal. Together, these data establish JMJD1C as an important mediator of MLL-AF9- and HOXA9-driven LSC function that is largely dispensable for HSC function.
| S-EPMC4767347 | biostudies-literature
Project description:Through a targeted knockdown (KD) screen of chromatin regulatory genes, we identified the EP400 complex components EPC1 and EPC2 as critical oncogenic cofactors in acute myeloid leukemia (AML). EPC1 and EPC2 were required for the clonogenic potential of human AML cells of multiple molecular subtypes. Focusing on MLL-mutated AML as an exemplar, Epc1 or Epc2 KD-induced apoptosis of murine MLL-AF9 AML cells and abolished leukemia stem cell potential. By contrast, normal hematopoietic stem and progenitor cells (HSPC) were spared. Similar selectivity was observed for human primary AML cells versus normal CD34(+) HSPC. In keeping with these distinct functional consequences, Epc1 or Epc2 KD-induced divergent transcriptional consequences in murine MLL-AF9 granulocyte-macrophage progenitor-like (GMP) cells versus normal GMP, with a signature of increased MYC activity in leukemic but not normal cells. This was caused by accumulation of MYC protein and was also observed following KD of other EP400 complex genes. Pharmacological inhibition of MYC:MAX dimerization, or concomitant MYC KD, reduced apoptosis following EPC1 KD, linking the accumulation of MYC to cell death. Therefore, EPC1 and EPC2 are components of a complex that directly or indirectly serves to prevent MYC accumulation and AML cell apoptosis, thus sustaining oncogenic potential.
| S-EPMC3998875 | biostudies-literature
Project description:Histone demethylation is known to regulate transcription, but its role in other processes is largely unknown. We report a role for the histone demethylase LSD1/KDM1A in the DNA damage response (DDR). We show that LSD1 is recruited directly to sites of DNA damage. H3K4 dimethylation, a major substrate for LSD1, is reduced at sites of DNA damage in an LSD1-dependent manner. The E3 ubiquitin ligase RNF168 physically interacts with LSD1 and we find this interaction to be important for LSD1 recruitment to DNA damage sites. Although loss of LSD1 did not affect the initial formation of pH2A.X foci, 53BP1 and BRCA1 complex recruitment were reduced upon LSD1 knockdown. Mechanistically, this was likely a result of compromised histone ubiquitylation preferentially in late S/G2. Consistent with a role in the DDR, knockdown of LSD1 resulted in moderate hypersensitivity to ?-irradiation and increased homologous recombination. Our findings uncover a direct role for LSD1 in the DDR and place LSD1 downstream of RNF168 in the DDR pathway.
| S-EPMC3824007 | biostudies-other
Project description:A growing body of data suggests the importance of epigenetic mechanisms in cancer. Polycomb repressive complex 2 (PRC2) has been implicated in self-renewal and cancer progression, and its components are overexpressed in many cancers. However, its role in cancer development and progression remains unclear. We used conditional alleles for the PRC2 components enhancer of zeste 2 (Ezh2) and embryonic ectoderm development (Eed) to characterize the role of PRC2 function in leukemia development and progression. Compared with wild-type leukemia, Ezh2-null MLL-AF9-mediated acute myeloid leukemia (AML) failed to accelerate upon secondary transplantation. However, Ezh2-null leukemias maintained self-renewal up to the third round of transplantation, indicating that Ezh2 is not strictly required for MLL-AF9 AML, but plays a role in leukemia progression. Genome-wide analyses of PRC2-mediated trimethylation of histone 3 demonstrated locus-specific persistence of H3K27me3 despite inactivation of Ezh2, suggesting partial compensation by Ezh1. In contrast, inactivation of the essential PRC2 gene, Eed, led to complete ablation of PRC2 function, which was incompatible with leukemia growth. Gene expression array analyses indicated more profound gene expression changes in Eed-null compared with Ezh2-null leukemic cells, including down-regulation of Myc target genes and up-regulation of PRC2 targets. Manipulating PRC2 function may be of therapeutic benefit in AML.
| S-EPMC3324004 | biostudies-literature