Project description:Rearrangements involving the NUP98 gene resulting in fusions to several partner genes occur in acute myeloid leukemia and myelodysplastic syndromes. This study demonstrates that the second FG repeat domain of the NUP98 moiety of the NUP98-HOXA9 fusion protein is important for its cell immortalization and leukemogenesis activities. We demonstrate that NUP98-HOXA9 interacts with MLL via this FG repeat domain and that, in the absence of MLL, NUP98-HOXA9-induced cell immortalization and leukemogenesis are severely inhibited. Molecular analyses indicate that MLL is important for the recruitment of NUP98-HOXA9 to the HOXA locus and for NUP98-HOXA9-induced HOXA gene expression. Our data indicate that MLL is crucial for NUP98-HOXA9 leukemia initiation.
Project description:HOXA9 and MEIS1 are essential downstream effectors of the MLL-AF9 oncoprotein during leukemia induction. Leukemia derived from MLL-AF9-transduced LSK cells has a more aggressive phenotype than that derived from HOXA9/MEIS1-transduced LSK cells. To determine differential miRNA expression that contributes to increased aggressiveness in MLL-AF9-induced leukemia, miRCURY LNA microRNA Array was performed on LSK cells transduced with MLL-AF9 versus HOXA/MEIS1 oncogenes.
Project description:Accumulating evidence indicates that HOXA9 dysregulation is sufficient and necessary for leukemic transformation. Leukemia subtypes showing HOXA9 overexpression include those carrying MLL gene rearrangements (MLL-r), NPM1c mutations, and other genetic alterations. HOXA9 protein is a poor therapeutic target as it lacks targetable pocket domains. Therefore, understanding HOXA9’s functional downstream genes and its regulation might provide alternative therapeutic targets. However, it remains largely unknown how HOXA9, as a homeobox transcriptional factor, binds to noncoding regulatory sequences and controls the downstream genes in MLL-r leukemia and across leukemias of other genetic subtypes. In this study, we have successfully conducted dropout CRISPR screens in the MLL-r SEM cell line stably expressing Cas9 against ~1,800 HOXA9 binding peaks. Integrative data analysis identified six reproducible noncoding hits, including a positive control located in the distal enhancer of FLT3. Cas9-editing and dCas9-KRAB silencing HOXA9’s binding site in distal region of FLT3 reduced transcription and impaired cell proliferation in vitro and in vivo. In addition, RNA-seq and Q-PCR analysis further identified the functional relevant downstream genes upon CRISPR editing of other candidate HOXA9-bound noncoding segments, including survival essential genes as XBP1, JUN and BAHCC1. In summary, the work is significant as it will advance our understanding of how HOXA9-associated transcription programs reconstruct the regulatory network specifying MLL-r dependency. Moreover, our study will promote the future development of HOXA9-mediated noncoding regulation, and alternative therapeutic targets in HOXA9-driven (including HOXA9 and possibly NUP98-HOXA9 subtype) leukemia in patients.
Project description:Accumulating evidence indicates that HOXA9 dysregulation is sufficient and necessary for leukemic transformation. Leukemia subtypes showing HOXA9 overexpression include those carrying MLL gene rearrangements (MLL-r), NPM1c mutations, and other genetic alterations. HOXA9 protein is a poor therapeutic target as it lacks targetable pocket domains. Therefore, understanding HOXA9’s functional downstream genes and its regulation might provide alternative therapeutic targets. However, it remains largely unknown how HOXA9, as a homeobox transcriptional factor, binds to noncoding regulatory sequences and controls the downstream genes in MLL-r leukemia and across leukemias of other genetic subtypes. In this study, we have successfully conducted dropout CRISPR screens in the MLL-r SEM cell line stably expressing Cas9 against ~1,800 HOXA9 binding peaks. Integrative data analysis identified six reproducible noncoding hits, including a positive control located in the distal enhancer of FLT3. Cas9-editing and dCas9-KRAB silencing HOXA9’s binding site in distal region of FLT3 reduced transcription and impaired cell proliferation in vitro and in vivo. In addition, RNA-seq and Q-PCR analysis further identified the functional relevant downstream genes upon CRISPR editing of other candidate HOXA9-bound noncoding segments, including survival essential genes as XBP1, JUN and BAHCC1. In summary, the work is significant as it will advance our understanding of how HOXA9-associated transcription programs reconstruct the regulatory network specifying MLL-r dependency. Moreover, our study will promote the future development of HOXA9-mediated noncoding regulation, and alternative therapeutic targets in HOXA9-driven (including HOXA9 and possibly NUP98-HOXA9 subtype) leukemia in patients.
Project description:Accumulating evidence indicates that HOXA9 dysregulation is sufficient and necessary for leukemic transformation. Leukemia subtypes showing HOXA9 overexpression include those carrying MLL gene rearrangements (MLL-r), NPM1c mutations, and other genetic alterations. HOXA9 protein is a poor therapeutic target as it lacks targetable pocket domains. Therefore, understanding HOXA9’s functional downstream genes and its regulation might provide alternative therapeutic targets. However, it remains largely unknown how HOXA9, as a homeobox transcriptional factor, binds to noncoding regulatory sequences and controls the downstream genes in MLL-r leukemia and across leukemias of other genetic subtypes. In this study, we have successfully conducted dropout CRISPR screens in the MLL-r SEM cell line stably expressing Cas9 against ~1,800 HOXA9 binding peaks. Integrative data analysis identified six reproducible noncoding hits, including a positive control located in the distal enhancer of FLT3. Cas9-editing and dCas9-KRAB silencing HOXA9’s binding site in distal region of FLT3 reduced transcription and impaired cell proliferation in vitro and in vivo. In addition, RNA-seq and Q-PCR analysis further identified the functional relevant downstream genes upon CRISPR editing of other candidate HOXA9-bound noncoding segments, including survival essential genes as XBP1, JUN and BAHCC1. In summary, the work is significant as it will advance our understanding of how HOXA9-associated transcription programs reconstruct the regulatory network specifying MLL-r dependency. Moreover, our study will promote the future development of HOXA9-mediated noncoding regulation, and alternative therapeutic targets in HOXA9-driven (including HOXA9 and possibly NUP98-HOXA9 subtype) leukemia in patients.
Project description:Accumulating evidence indicates that HOXA9 dysregulation is sufficient and necessary for leukemic transformation. Leukemia subtypes showing HOXA9 overexpression include those carrying MLL gene rearrangements (MLL-r), NPM1c mutations, and other genetic alterations. HOXA9 protein is a poor therapeutic target as it lacks targetable pocket domains. Therefore, understanding HOXA9’s functional downstream genes and its regulation might provide alternative therapeutic targets. However, it remains largely unknown how HOXA9, as a homeobox transcriptional factor, binds to noncoding regulatory sequences and controls the downstream genes in MLL-r leukemia and across leukemias of other genetic subtypes. In this study, we have successfully conducted dropout CRISPR screens in the MLL-r SEM cell line stably expressing Cas9 against ~1,800 HOXA9 binding peaks. Integrative data analysis identified six reproducible noncoding hits, including a positive control located in the distal enhancer of FLT3. Cas9-editing and dCas9-KRAB silencing HOXA9’s binding site in distal region of FLT3 reduced transcription and impaired cell proliferation in vitro and in vivo. In addition, RNA-seq and Q-PCR analysis further identified the functional relevant downstream genes upon CRISPR editing of other candidate HOXA9-bound noncoding segments, including survival essential genes as XBP1, JUN and BAHCC1. In summary, the work is significant as it will advance our understanding of how HOXA9-associated transcription programs reconstruct the regulatory network specifying MLL-r dependency. Moreover, our study will promote the future development of HOXA9-mediated noncoding regulation, and alternative therapeutic targets in HOXA9-driven (including HOXA9 and possibly NUP98-HOXA9 subtype) leukemia in patients.
Project description:Accumulating evidence indicates that HOXA9 dysregulation is sufficient and necessary for leukemic transformation. Leukemia subtypes showing HOXA9 overexpression include those carrying MLL gene rearrangements (MLL-r), NPM1c mutations, and other genetic alterations. HOXA9 protein is a poor therapeutic target as it lacks targetable pocket domains. Therefore, understanding HOXA9’s functional downstream genes and its regulation might provide alternative therapeutic targets. However, it remains largely unknown how HOXA9, as a homeobox transcriptional factor, binds to noncoding regulatory sequences and controls the downstream genes in MLL-r leukemia and across leukemias of other genetic subtypes. In this study, we have successfully conducted dropout CRISPR screens in the MLL-r SEM cell line stably expressing Cas9 against ~1,800 HOXA9 binding peaks. Integrative data analysis identified six reproducible noncoding hits, including a positive control located in the distal enhancer of FLT3. Cas9-editing and dCas9-KRAB silencing HOXA9’s binding site in distal region of FLT3 reduced transcription and impaired cell proliferation in vitro and in vivo. In addition, RNA-seq and Q-PCR analysis further identified the functional relevant downstream genes upon CRISPR editing of other candidate HOXA9-bound noncoding segments, including survival essential genes as XBP1, JUN and BAHCC1. In summary, the work is significant as it will advance our understanding of how HOXA9-associated transcription programs reconstruct the regulatory network specifying MLL-r dependency. Moreover, our study will promote the future development of HOXA9-mediated noncoding regulation, and alternative therapeutic targets in HOXA9-driven (including HOXA9 and possibly NUP98-HOXA9 subtype) leukemia in patients.
Project description:Accumulating evidence indicates that HOXA9 dysregulation is sufficient and necessary for leukemic transformation. Leukemia subtypes showing HOXA9 overexpression include those carrying MLL gene rearrangements (MLL-r), NPM1c mutations, and other genetic alterations. HOXA9 protein is a poor therapeutic target as it lacks targetable pocket domains. Therefore, understanding HOXA9’s functional downstream genes and its regulation might provide alternative therapeutic targets. However, it remains largely unknown how HOXA9, as a homeobox transcriptional factor, binds to noncoding regulatory sequences and controls the downstream genes in MLL-r leukemia and across leukemias of other genetic subtypes. In this study, we have successfully conducted dropout CRISPR screens in the MLL-r SEM cell line stably expressing Cas9 against ~1,800 HOXA9 binding peaks. Integrative data analysis identified six reproducible noncoding hits, including a positive control located in the distal enhancer of FLT3. Cas9-editing and dCas9-KRAB silencing HOXA9’s binding site in distal region of FLT3 reduced transcription and impaired cell proliferation in vitro and in vivo. In addition, RNA-seq and Q-PCR analysis further identified the functional relevant downstream genes upon CRISPR editing of other candidate HOXA9-bound noncoding segments, including survival essential genes as XBP1, JUN and BAHCC1. In summary, the work is significant as it will advance our understanding of how HOXA9-associated transcription programs reconstruct the regulatory network specifying MLL-r dependency. Moreover, our study will promote the future development of HOXA9-mediated noncoding regulation, and alternative therapeutic targets in HOXA9-driven (including HOXA9 and possibly NUP98-HOXA9 subtype) leukemia in patients.
Project description:Accumulating evidence indicates that HOXA9 dysregulation is sufficient and necessary for leukemic transformation. Leukemia subtypes showing HOXA9 overexpression include those carrying MLL gene rearrangements (MLL-r), NPM1c mutations, and other genetic alterations. HOXA9 protein is a poor therapeutic target as it lacks targetable pocket domains. Therefore, understanding HOXA9’s functional downstream genes and its regulation might provide alternative therapeutic targets. However, it remains largely unknown how HOXA9, as a homeobox transcriptional factor, binds to noncoding regulatory sequences and controls the downstream genes in MLL-r leukemia and across leukemias of other genetic subtypes. In this study, we have successfully conducted dropout CRISPR screens in the MLL-r SEM cell line stably expressing Cas9 against ~1,800 HOXA9 binding peaks. Integrative data analysis identified six reproducible noncoding hits, including a positive control located in the distal enhancer of FLT3. Cas9-editing and dCas9-KRAB silencing HOXA9’s binding site in distal region of FLT3 reduced transcription and impaired cell proliferation in vitro and in vivo. In addition, RNA-seq and Q-PCR analysis further identified the functional relevant downstream genes upon CRISPR editing of other candidate HOXA9-bound noncoding segments, including survival essential genes as XBP1, JUN and BAHCC1. In summary, the work is significant as it will advance our understanding of how HOXA9-associated transcription programs reconstruct the regulatory network specifying MLL-r dependency. Moreover, our study will promote the future development of HOXA9-mediated noncoding regulation, and alternative therapeutic targets in HOXA9-driven (including HOXA9 and possibly NUP98-HOXA9 subtype) leukemia in patients.
Project description:Nuclear receptor-binding SET domain protein 1 (NSD1) prototype is a family of mammalian histone methyltransferases (NSD1, NSD2/MMSET/WHSC1, NSD3/WHSC1L1) that are essential in development and are mutated in human acute myeloid leukemia (AML), overgrowth syndromes, multiple myeloma and lung cancers. In AML, the recurring t(5;11)(q35;p15.5) translocation fuses NSD1 to nucleoporin-98 (NUP98). Here, we present the first characterization of the transforming properties and molecular mechanisms of NUP98-NSD1. We demonstrate that NUP98-NSD1 induces AML in vivo, sustains self-renewal of myeloid stem cells in vitro, and enforces expression of the HoxA7, HoxA9, HoxA10 and Meis1 proto-oncogenes. Mechanistically, NUP98-NSD1 binds genomic elements adjacent to HoxA7 and HoxA9, maintains histone H3 Lys 36 (H3K36) methylation and histone acetylation, and prevents EZH2-mediated transcriptional repression of the Hox-A locus during differentiation. Deletion of the NUP98 FG-repeat domain, or mutations in NSD1 that inactivate the H3K36 methyltransferase activity or that prevent binding of NUP98-NSD1 to the Hox-A locus precluded both Hox-A gene activation and myeloid progenitor immortalization. We propose that NUP98-NSD1 prevents EZH2-mediated repression of Hox-A locus genes by colocalizing H3K36 methylation and histone acetylation at regulatory DNA elements. This report is the first to link deregulated H3K36 methylation to tumorigenesis and to link NSD1 to transcriptional regulation of the Hox-A locus. Experiment Overall Design: Total RNA was extracted from stably transformed progenitors cultured in vitro and the expression levels of mRNA transcripts quantified using the Affymetrix GeneChip Mouse Genome 430 2.0 array, as previously described. The GEO database accession numbers: for progenitors immortalized by HoxA9 (GSM190542, GSM190546, GSM190547); for progenitors immortalized by coexpressed HoxA9 plus Meis1 (GSM190548, GSM190549, GSM190550); for progenitors immortalized by NUP98-NSD1 (GSM190551, GSM190552, GSM190553); and for progenitors immortalized by MLL-ENL (GSM190554). Experiment Overall Design: NOTE: CEL files and dChip data were requested by GEO but not provided.