The H3.3K27M oncohistone antagonizes reprogramming in Drosophila
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA679825 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR13093832_1.fastq.gz | Fastqsanger.gz | |||
| SRR13093832_2.fastq.gz | Fastqsanger.gz | |||
| SRR13093833_1.fastq.gz | Fastqsanger.gz | |||
| SRR13093833_2.fastq.gz | Fastqsanger.gz | |||
| SRR13093834_1.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 222 |
Similar Datasets
Project description:Development proceeds by the activation of genes by transcription factors and the inactivation of others by chromatin-mediated gene silencing. In some cases development can be reversed or redirected by mis-expression of master regulator transcription factors. This must involve the activation of previously silenced genes, and such developmental aberrations are thought to underlie a variety of cancers. Here, we express the wing-specific Vestigial master regulator to reprogram the developing eye, and test the role of silencing in reprogramming using an H3.3K27M oncohistone mutation that dominantly inhibits histone H3K27 trimethylation. We find that expression of the oncohistone blocks eye-to-wing reprogramming. CUT&Tag chromatin profiling of mutant tissues shows that H3K27me3 domains are globally reduced with oncohistone expression, suggesting that previous developmental programs must be silenced for effective transformation. Strikingly, mis-expressed Vg and H3.3K27M synergize to stimulate overgrowth of eye tissue, a phenotype that resembles that of mutations in Polycomb Repressive Complex 1 components. Our results imply that growth dysregulation can result from the simple combination of crippled silencing and transcription factor mis-expression, an effect that may explain the origins of oncohistone-bearing cancers.
2021-06-15 | GSE161919 | GEO
Project description:Development proceeds by the activation of genes by transcription factors and the inactivation of others by chromatin-mediated gene silencing. In certain cases development can be reversed or redirected by mis-expression of master regulator transcription factors. This must involve the activation of previously silenced genes, and such developmental aberrations are thought to underlie a variety of cancers. Here, we express the wing-specific Vestigial master regulator to reprogram the developing eye, and test the role of silencing in reprogramming using an H3.3K27M oncohistone mutation that dominantly inhibits histone H3K27 trimethylation. We find that production of the oncohistone blocks eye-to-wing reprogramming. CUT&Tag chromatin profiling of mutant tissues shows that H3K27me3 of domains is generally reduced upon oncohistone production, suggesting that a previous developmental program must be silenced for effective transformation. Strikingly, Vg and H3.3K27M synergize to stimulate overgrowth of eye tissue, a phenotype that resembles that of mutations in Polycomb silencing components. Transcriptome profiling of elongating RNA Polymerase II implicates the mis-regulation of signaling factors in overgrowth. Our results demonstrate that growth dysregulation can result from the simple combination of crippled silencing and transcription factor mis-expression, an effect that may explain the origins of oncohistone-bearing cancers.
| S-EPMC8320987 | biostudies-literature
Project description:Substitution of lysine 27 with methionine in histone H3.3 is a recently discovered driver mutation of pediatric high-grade gliomas. Tumor cells carrying the mutation show a dramatic decrease in H3K27me3 levels due to physical inhibition of PRC2 methyltransferase activity. Here we use a C. elegans model to quantify the antagonistic effects of the H3.3K27M oncohistone on H3K27 trimethylation genome wide. We demonstrate that PRC2 is locally both simulated by H3K27me3 and inhibited by the oncohistone in a concentration-dependent manner.
2019-04-26 | GSE117531 | GEO
Project description:Substitution of lysine 27 with methionine in histone H3.3 is a recently discovered driver mutation of pediatric high-grade gliomas. Tumor cells carrying the mutation show a dramatic decrease in H3K27me3 levels due to physical inhibition of PRC2 methyltransferase activity. Here we use a C. elegans model to quantify the antagonistic effects of the H3.3K27M oncohistone on H3K27 trimethylation genome wide. We demonstrate that PRC2 is locally both simulated by H3K27me3 and inhibited by the oncohistone in a concentration-dependent manner.
2019-04-26 | GSE117471 | GEO
Project description:Histone H3-mutant gliomas are deadly brain tumors characterized by a dysregulated epigenome and stalled differentiation. In contrast to the extensive datasets available on tumor cells, limited information exists on their tumor microenvironment (TME), including the immune infiltrate. Here, we characterize the TME of H3.3K27M and G34R/V-mutant gliomas, and multiple H3.3K27M mouse models, using transcriptomic and proteomic, including spatial single-cell approaches. Resolution of immune lineages indicates uniform high-infiltration of H3-mutant gliomas with diverse myeloid populations, high-level expression of immune checkpoints, and scarce lymphoid cells, findings uniformly reproduced in all H3.3K27M models tested. We show these myeloid populations communicate with H3-mutant cells mediating immunosuppression and sustaining tumor formation and maintenance. Dual inhibition of myeloid cells and immune checkpoints showed significant therapeutic benefit in pre-clinical syngeneic models. Our findings provide valuable characterization of the TME of oncohistone-mutant gliomas, and insights into means to modulate the myeloid infiltrate for the benefit of patients.
2024-07-02 | GSE241985 | GEO
Project description:Gain-of-function mutations in histone 3 (H3) variants are found in a large proportion ofpediatric high-grade gliomas (pHGG) and are often associated with p53 loss and PDGFRA amplification. However, a lack of faithful models has hampered investigation of disease mechanisms and preclinical development. Here, we describe a somatic mouse model of H3.3K27M-driven HGG, which faithfully recapitulates human H3.3K27M pHGG. H3.3K27M and p53 loss are sufficient for neoplastic transformation but only within a specific window of brain development. In this model, H3.3K27M primes the PDGFRA pathway during transformation, and accordingly gain of wild-type PDGFRA decreases latency and increases invasion. Finally, we reveal a previously underappreciated dynamic regulation of H3K27 trimethylation at specific loci. Overall, this experimental model provides key insights into oncohistone-driven pHGG pathogenesis and will enable investigations of future therapies.
2017-10-27 | GSE100826 | GEO
Project description:Gain-of-function mutations in histone 3 (H3) variants are found in a large proportion ofpediatric high-grade gliomas (pHGG) and are often associated with p53 loss and PDGFRA amplification. However, a lack of faithful models has hampered investigation of disease mechanisms and preclinical development. Here, we describe a somatic mouse model of H3.3K27M-driven HGG, which faithfully recapitulates human H3.3K27M pHGG. H3.3K27M and p53 loss are sufficient for neoplastic transformation but only within a specific window of brain development. In this model, H3.3K27M primes the PDGFRA pathway during transformation, and accordingly gain of wild-type PDGFRA decreases latency and increases invasion. Finally, we reveal a previously underappreciated dynamic regulation of H3K27 trimethylation at specific loci. Overall, this experimental model provides key insights into oncohistone-driven pHGG pathogenesis and will enable investigations of future therapies.
2017-10-27 | GSE95168 | GEO
Project description:Gain-of-function mutations in histone 3 (H3) variants are found in a large proportion ofpediatric high-grade gliomas (pHGG) and are often associated with p53 loss and PDGFRA amplification. However, a lack of faithful models has hampered investigation of disease mechanisms and preclinical development. Here, we describe a somatic mouse model of H3.3K27M-driven HGG, which faithfully recapitulates human H3.3K27M pHGG. H3.3K27M and p53 loss are sufficient for neoplastic transformation but only within a specific window of brain development. In this model, H3.3K27M primes the PDGFRA pathway during transformation, and accordingly gain of wild-type PDGFRA decreases latency and increases invasion. Finally, we reveal a previously underappreciated dynamic regulation of H3K27 trimethylation at specific loci. Overall, this experimental model provides key insights into oncohistone-driven pHGG pathogenesis and will enable investigations of future therapies.
2017-10-27 | GSE95167 | GEO
Project description:Gain-of-function mutations in histone 3 (H3) variants are found in a large proportion of pediatric high-grade gliomas (pHGG) and are often associated with p53 loss and PDGFRA amplification. However, a lack of faithful models has hampered investigation of disease mechanisms and preclinical development. Here, we describe a somatic mouse model of H3.3K27M-driven HGG, which faithfully recapitulates human H3.3K27M pHGG. H3.3K27M and p53 loss are sufficient for neoplastic transformation but only within a specific window of brain development. In this model, H3.3K27M primes the PDGFRA pathway during transformation, and accordingly gain of wild-type PDGFRA decreases latency and increases invasion. Finally, we reveal a previously underappreciated dynamic regulation of H3K27 trimethylation at specific loci. Overall, this experimental model provides key insights into oncohistone-driven pHGG pathogenesis and will enable investigations of future therapies.
2017-10-27 | GSE95277 | GEO
Project description:Diffuse intrinsic pontine gliomas (DIPG) are paediatric malignant gliomas developing in the brainstem, where resection is unattainable, leaving palliative radiotherapy as the major standard of care. Patients with DIPG have dismal prognosis of 9-12 months of survival and currently there is no effective therapy. Over 80% of DIPGs harbour a mutation in histone 3 (H3.3 or H3.1) resulting in a lysine to methionine substitution (H3K27M). H3K27M causes global epigenetic alterations (a loss of H3K27 trimethylation and an increase H3K27 acetylation) resulting in aberrant gene expression. To date, no therapeutic strategy exists to suppress the levels of oncogenic H3K27M. We show that pan-HDAC inhibitors (HDACi) lead to the temporary but significant reduction in the H3.3K27M protein (up to 80%) in multiple glioma cell lines expressing the H3.3K27M histone variant, without changes in the H3F3A mRNA expression. The H3.3K27M occupancy at the chromatin is greatly reduced upon HDACi (SB939) treatment, as shown by ChIPseq analysis. H3.3K27M loss is most striking at SB939-upregulated genes suggesting re-expression of repressed genes. Certain H3K27M-dependent genes become downregulated in response to SB939 treatment. We discover that the SB939-mediated loss of H3.3K27M is partially blocked by a lysosomal inhibitor chloroquine. Moreover, the loss of H3.3K27M is facilitated by co-occurrence of H2A.Z, as evidenced by the knock-down of H2A.Z histone isoforms. ChIPseq analysis confirms the occupancy of H3.3K27M and H2A.Z at the same SB939-inducible genes. Altogether, we provide new insight into disease-specific mechanism of HDAC inhibition and demonstrate pharmacological modulation of the oncogenic H3.3K27M protein levels. These findings open a new possibility to directly target the H3.3K27M oncohistone, which may be exploited in future therapies.
2024-05-01 | GSE232283 | GEO