Targeting the scaffolding role of LSD1(KDM1A) poises acute myeloid leukemia cells for Retinoic Acid induced differentiation [RNA-seq]
Ontology highlight
ABSTRACT:
OTHER RELATED OMICS DATASETS IN: PXD012954
ORGANISM(S): Homo sapiens
PROVIDER: GSE128529 | GEO | 2020/04/20
REPOSITORIES: GEO
Similar Datasets
Project description:The histone demethylase LSD1 is deregulated in several tumors, including leukemias, providing the rationale for the clinical use of LSD1 inhibitors. In acute promyelocytic leukemia (APL), pharmacological doses of retinoic acid (RA) induce differentiation of APL cells through degradation of the PML-RAR oncogene. APL cells are resistant to LSD1 inhibition or knock-out, but LSD1 inhibition sensitizes them to physiological doses of RA without altering the stability of PML-RAR, and extends survival of leukemic mice upon RA treatment. Non-enzymatic activities of LSD1 are essential to block differentiation of leukemic cells, while the combination of LSD1 inhibitors (or LSD1 knock-out) with low doses of RA releases a differentiation-associated gene expression program, not strictly dependent on changes in histone H3K4 methylation (known substrate of LSD1). An integrated proteomic/epigenomic/mutational analysis showed that LSD1 inhibitors alter the recruitment of LSD1-containing complexes to chromatin through inhibition of the interaction between LSD1 and GFI1, a relevant transcription factor in hematopoiesis.
2020-05-26 | PXD012954 | Pride
Project description:The histone demethylase LSD1 is deregulated in several tumors, including leukemias, providing the rationale for the clinical use of LSD1 inhibitors . In acute promyelocytic leukemia (APL), pharmacological doses of retinoic acid (RA) induce differentiation of APL cells through degradation of the PML-RAR oncogene. APL cells are resistant to LSD1 inhibition or knock-out, but LSD1 inhibition sensitizes them to physiological doses of RA without altering the stability of PML-RAR, and extends survival of leukemic mice upon RA treatment. Non-enzymatic activities of LSD1 are essential to block differentiation of leukemic cells, while the combination of LSD1 inhibitors (or LSD1 knock-out) with low doses of RA releases a differentiation-associated gene expression program, not strictly dependent on changes in histone H3K4 methylation (known substrate of LSD1). An integrated proteomic/epigenomic/mutational analysis showed that LSD1 inhibitors alter the recruitment of LSD1-containing complexes to chromatin through inhibition of the interaction between LSD1 and GFI1, a relevant transcription factor in hematopoiesis.
2020-04-20 | GSE128528 | GEO
Project description:The aim of this study is to identify microRNAs (miRNAs) transcriptionnally regulated by retinoic acid (RA). For that purpose we have used the RA-based treatment of the Acute Promyelocytic Leukemia (APL) as a model. This malignancy is characterised by a differentiation arrest of granulopoiesis at the promyelocytic stage. APL is molecularly associated with reciprocal translocations that always involve the retinoic acid receptor a (RARa). In the vast majority of APL cases, a t(15;17) chromosomal translocation fuses the genes encoding the promyelocytic leukemia protein PML and RARa. The resulting PML-RARa is a transcriptional repressor that impedes the expression of RA-regulated genes notably through an aberrant recruitment of transcriptional repressors and histone deacetylases. Consequently, these genes become insensitive to physiological doses (nanoM) of all-trans-retinoic acid (ATRA) but pharmacological doses (microM), overcome the PML-RARa-mediated repression and restore normal transcription and granulocytic differentiation. The restorative effects of RA can be reproduced in vitro in the NB4 cells, which were derived from an APL patient. These cells provide an excellent model to study the transcriptional deregulations that arise in APL and the molecular effects of the anti-cancerous RA-based treatment. We also used in this study the RA-resistant cells, namely NB4-LR1 and NB4-LR2 cells. The NB4-LR1 cells do transcriptionally respond to ATRA but do not maturate. In contrast, the NB4-LR2 cells show a clear defect in RA signaling, as they harbor a truncated form of PML-RAR protein that is not sensitive to pharmacological doses of RA. First, we plan to characterize miRNAs-repressed by PML-RAR. We reasoned that if some miRNAs are repressed by this protein, then pharmacological doses of RA should abolish this repression and lead to an increase in the level of expression of the corresponding miRNAs. NB4, NB4-LR1 and NB4-LR2 cells will thus be treated for 16h with ATRA (1 microM), and miRNAs profiles will be compared. We anticipate that, the expression of a potential miRNA-repressed by PML-RAR should be up-regulated by ATRA in both NB4 and NB4-LR1 cells but remain unchanged in NB4-LR2 cells. This expression pattern should in fact be similar to those observed for known RA-regulated genes, such as RARb, a well characterized target of the RARa and PML-RAR proteins. Importantly, this experimental procedure was already validated with the identification of a miRNA repressed by PML-RAR (patent Lecellier et al. #WO 2006/048553). MiRNAs candidates obtained will then be validated by chromatin immunoprecipitation using anti-RARa and anti-PML antibodies, followed by luciferase assays in presence or absence of ATRA. Keywords: retinoic acid-mediated gene regulation To characterize miRNAs regulated by PML-RAR.
2008-11-17 | E-GEOD-11379 | biostudies-arrayexpress
Project description:The aim of this study is to identify microRNAs (miRNAs) transcriptionnally regulated by retinoic acid (RA). For that purpose we have used the RA-based treatment of the Acute Promyelocytic Leukemia (APL) as a model. This malignancy is characterised by a differentiation arrest of granulopoiesis at the promyelocytic stage. APL is molecularly associated with reciprocal translocations that always involve the retinoic acid receptor a (RARa). In the vast majority of APL cases, a t(15;17) chromosomal translocation fuses the genes encoding the promyelocytic leukemia protein PML and RARa. The resulting PML-RARa is a transcriptional repressor that impedes the expression of RA-regulated genes notably through an aberrant recruitment of transcriptional repressors and histone deacetylases. Consequently, these genes become insensitive to physiological doses (nanoM) of all-trans-retinoic acid (ATRA) but pharmacological doses (microM), overcome the PML-RARa-mediated repression and restore normal transcription and granulocytic differentiation. The restorative effects of RA can be reproduced in vitro in the NB4 cells, which were derived from an APL patient. These cells provide an excellent model to study the transcriptional deregulations that arise in APL and the molecular effects of the anti-cancerous RA-based treatment. We also used in this study the RA-resistant cells, namely NB4-LR1 and NB4-LR2 cells. The NB4-LR1 cells do transcriptionally respond to ATRA but do not maturate. In contrast, the NB4-LR2 cells show a clear defect in RA signaling, as they harbor a truncated form of PML-RAR protein that is not sensitive to pharmacological doses of RA. First, we plan to characterize miRNAs-repressed by PML-RAR. We reasoned that if some miRNAs are repressed by this protein, then pharmacological doses of RA should abolish this repression and lead to an increase in the level of expression of the corresponding miRNAs. NB4, NB4-LR1 and NB4-LR2 cells will thus be treated for 16h with ATRA (1 microM), and miRNAs profiles will be compared. We anticipate that, the expression of a potential miRNA-repressed by PML-RAR should be up-regulated by ATRA in both NB4 and NB4-LR1 cells but remain unchanged in NB4-LR2 cells. This expression pattern should in fact be similar to those observed for known RA-regulated genes, such as RARb, a well characterized target of the RARa and PML-RAR proteins. Importantly, this experimental procedure was already validated with the identification of a miRNA repressed by PML-RAR (patent Lecellier et al. #WO 2006/048553). MiRNAs candidates obtained will then be validated by chromatin immunoprecipitation using anti-RARa and anti-PML antibodies, followed by luciferase assays in presence or absence of ATRA. Keywords: retinoic acid-mediated gene regulation
2008-11-18 | GSE11379 | GEO
Project description:Many different molecular mechanisms have been suggested to be associated with PML-RAR dependent transformation of haematopoietic progenitors. Here, we investigated the role of PML-RAR and RXR in the organization of epigenetic structures at a genome-wide level. We identified 2722 high confidence PML-RAR binding sites in the leukemic model cell line NB4 and found PML-RAR colocalization with RXR to the vast majority of these binding regions. Importantly, these results could be corroborated and extended in primary blast cells of two APL patients. Through genome-wide epigenetic studies we show that treatment with pharmacological doses of all-trans retinoic acid ATRA induces global alterations in active H3 acetylation and repressive H3K27me3, H3K9me3 and DNA methylation chromatin modifications. However at the PML-RAR/RXR binding sites, ATRA only induces changes in H3 acetylation. These H3 acetylation alterations triggered by the loss of PML-RAR/RXR binding affect H3 acetylation and RNA polymerase II occupancy at nearby genes. Our results suggest that PML-RAR/RXR functions as a local chromatin modulator and that specific recruitment of histone deacetylase activities to genes important for haematopoietic differentiation, RAR signaling and epigenetic control is crucial to the transforming potential of PML-RAR/RXR. Examination of PML, RARa and RXR binding sites in leukemic cells before and after ATRA treatment, association with transcription via RNAPII occupancy and with chromatin modifications.
2009-12-17 | E-GEOD-18886 | biostudies-arrayexpress
Project description:Many different molecular mechanisms have been suggested to be associated with PML-RAR dependent transformation of haematopoietic progenitors. Here, we investigated the role of PML-RAR and RXR in the organization of epigenetic structures at a genome-wide level. We identified 2722 high confidence PML-RAR binding sites in the leukemic model cell line NB4 and found PML-RAR colocalization with RXR to the vast majority of these binding regions. Importantly, these results could be corroborated and extended in primary blast cells of two APL patients. Through genome-wide epigenetic studies we show that treatment with pharmacological doses of all-trans retinoic acid ATRA induces global alterations in active H3 acetylation and repressive H3K27me3, H3K9me3 and DNA methylation chromatin modifications. However at the PML-RAR/RXR binding sites, ATRA only induces changes in H3 acetylation. These H3 acetylation alterations triggered by the loss of PML-RAR/RXR binding affect H3 acetylation and RNA polymerase II occupancy at nearby genes. Our results suggest that PML-RAR/RXR functions as a local chromatin modulator and that specific recruitment of histone deacetylase activities to genes important for haematopoietic differentiation, RAR signaling and epigenetic control is crucial to the transforming potential of PML-RAR/RXR.
2009-12-17 | GSE18886 | GEO
Project description:Gene expression profiles in blasts from three APL patients expressing PML/RAR were assessed before and after treatment with 1 uM retinoic acid (RA) in vitro for four hours. We then studied a U937 clone conditionally expressing PML/RAR (U937-PR), (Grignani et al. 1993) (Alcalay et al. 2003), and compared the gene expression profile prior to and after 4 hours of treatment with 1 uM RA, to that obtained from a cell line bearing an empty vector (U937-MT). For each sample, biotinylated cRNA targets were synthesized starting from 5ug of total RNA, and hybridized to the complete set of HG-U133 Affymetrix oligonucleotide chips, which explores the expression of approximately 45,000 human transcripts. Results were analyzed using MASv5 and further elaborated with the GenePicker software. GeneChip probe sets regulated by RA in each sample were clustered into non-redundant regulated genes according to UniGene release Hs.166.
2004-12-31 | E-MEXP-149 | biostudies-arrayexpress
Project description:The therapy-induced PML/RARA catabolism elicits the loss of APL-initiating cell self-renewal through PML NB reformation and P53 activation. These results explain the curative activity of the RA/arsenic combination, the resistance to RA of PLZF/RARA-driven APLs and they raise the prospect that activation of this PML/P53 checkpoint might have therapeutic values in other malignancies. Gene expression profiles of 36 transgenic induced APL and 36 viral transduction APL were hybridized using Affymetrix Mouse Gene 1.0 ST Arrays
2014-01-11 | E-GEOD-51723 | biostudies-arrayexpress
Project description:The oncogenic fusion protein PML/RAR is expressed in most cases of acute promyelocytic leukemia (APL). In transgenic models, PML/RAR is able to induce a preleukemic state. However, it is not sufficient to induce leukemia, which develops with low frequency (~50%) and long latency (about 1 year). These data indicate that secondary genetic cooperating alterations are required in order to induce leukemia. In an effort to identify the genes that cooperate in the leukemogenesis PML/RAR-dependent, we performed an insertional mutagenesis screening infecting the PML/RAR KI mice with Moloney Murine Leukemia Virus (MLV). The infection of the PML/RAR KI mice significantly accelerated the onset (~6 months) and increased the penetrance (~75% of infected animals) of the leukemia. To identify genes mutated by the proviral integrations, flanking sequences of the retrovirus insertions were cloned by IPCR and analysed by parallel sequencing. We sequenced DNAs from the spleen of 48 independent leukemic mice. After filtering, ~133,000 reads were univocally mapped onto the mouse genome. Of them, ~131,000 were present more than once in the DNA from the same mouse and produced a total of 1,707 independent genomic insertions (retroviral insertion sites - RISs). To identify chromosomal regions that are frequently mutated by retrovirus insertions (common insertion sites; CISs), we evaluated the density of RISs distribution over the mouse genome, using statistical approaches that calculate the significance of RISs occurrence (p<0.05) within specific genomic regions (Monte Carlo simulation or Kernel Convolution). The two different approaches identified the same set of 221 CISs. Finally, we identified 271 genes putatively targeted by retroviral insertions in the 221 CISs. These putative targets appeared to be enriched in genes identified as relevant cancer-genes in different tumor types. Moreover, from a biological point of view, our screening was performed in saturating conditions. Therefore, to our knowledge, our is the first report of an exhaustive list of virtually all the mouse genes that functionally cooperate with PML/RAR in the induction of APL.
2016-12-31 | GSE72528 | GEO
Project description:RARA haploinsufficiency is an invariable consequence of t(15;17) reciprocal translocations in acute promyelocytic leukemia (APL). Furthermore, retinoids and RARA activity have been implicated in hematopoietic self-renewal, lineage commitment and neutrophil maturation. We and others therefore predicted that RARA haploinsufficiency would contribute to APL pathogenesis. To test this hypothesis we crossed RARA+/- mice with mice expressing PML-RARA from the Cathepsin G locus (mCG-PR). We found that RARA haploinsufficiency cooperated with PML-RARA, only modestly influencing the pre-leukemic and leukemic phenotype. Bone marrow from mCG-PR+/- x RARA+/- mice had decreased numbers of mature myeloid cells, increased ex vivo myeloid cell proliferation and an increased competitive advantage following transplantation. RARA haploinsufficiency did not alter mCG-PR dependent leukemic latency or penetrance, but did influence the distribution of leukemic cells; mCG-PR+/- x RARA+/- mice presented more commonly with low to normal white blood cell counts and with myeloid infiltration of lymph nodes. APL arising in these mice was responsive to ATRA, and had virtually no differences in expression profiling compared to tumors arising in mCG-PR+/- x RARA+/+ mice. These phenotypes were dependent on PML-RARA activity, since they were not detected in RARA+/- mice in the absence of the mCG-PR transgene. These data show that RARA haploinsufficiency (like PML haploinsufficiency and RARA-PML) can cooperate with PML-RARA to influence the pathogenesis and phenotype of APL in mice, but that PML-RARA is the driver of t(15;17) APL. RARA+/- mice were crossed with mice expressing PML-RARA from Cathepsin G locus (mCG-PR). Five leukemic mice were chosen from each of the mCG-PR+/-RARA+/- and mCG-PR+/-RARA+/+ strains and total RNA extracted from the spleen samples were analyzed using Affymetrics Mouse Exon 1.0 platform
2010-07-29 | E-GEOD-23291 | biostudies-arrayexpress