Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

EZH2 depletion potentiates MYC degradation in neuroblastoma and small-cell lung cancer

ABSTRACT: Efforts to therapeutically target EZH2 have generally focused on inhibition of its methyltransferase activity, although it remains less clear whether this is the central mechanism whereby EZH2 promotes cancer. We demonstrate that EZH2 interacts with both MYC family oncoproteins, C-MYC and N-MYC, and promotes their stabilization in a methyltransferase-independent manner. By competing against the SCFFbw7 ubiquitin ligase to bind MYC, EZH2 counteracted Fbw7-mediated MYC polyubiquitination and proteasomal degradation. Depletion, but not enzymatic inhibition, of EZH2 induced robust MYC degradation and inhibited tumor cell growth in MYC-driven neuroblastoma and small-cell lung cancer. These findings unveil the MYC family proteins as critical EZH2 oncogenic effectors and EZH2 pharmacologic degraders as potential MYC-selective cancer therapeutics, pointing out that MYC-driven cancers may develop inherent resistance to canonical EZH2 enzymatic inhibitors currently in clinical development.

ORGANISM(S): Homo sapiens

PROVIDER: GSE181782 | GEO | 2021/08/31

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

EZH2 depletion potentiates MYC degradation inhibiting neuroblastoma and small cell carcinoma tumor formation

Project description:Efforts to therapeutically target EZH2 have generally focused on inhibition of its methyltransferase activity, although it remains less clear whether this is the central mechanism whereby EZH2 promotes cancer. We demonstrate that EZH2 directly interacts with both MYC family oncoproteins, MYC and MYCN, and promotes their stabilization in a methyltransferase-independent manner. By competing against the SCFFBW7 ubiquitin ligase to bind MYC and MYCN, EZH2 counteracted FBW7-mediated MYC(N) polyubiquitination and proteasomal degradation. Depletion, but not enzymatic inhibition, of EZH2 induced robust MYC(N) degradation and inhibited tumor cell growth in MYC(N) driven neuroblastoma and small cell lung cancer. These findings unveil the MYC family proteins as global EZH2 oncogenic effectors and EZH2 pharmacologic degraders as potential MYC(N) targeted cancer therapeutics, pointing out that MYC(N) driven cancers may develop inherent resistance to the canonical EZH2 enzymatic inhibitors currently in clinical development.

2022-02-17 | PXD029652 | Pride

Dual regulation of Fbw7 function and oncogenic transformation by Usp28

2015-05-01 | GSE59354 | GEO

Dual regulation of Fbw7 function and oncogenic transformation by Usp28

Project description:Fbw7, the substrate recognition subunit of SCF(Fbw7) ubiquitin ligase, mediates turnover of multiple proto-oncoproteins and promotes its own degradation. Fbw7-mediated substrate degradation is antagonized by the Usp28 deubiquitinase. We now show, using knockout mice, that Usp28 preferentially deubiquitinates and stabilizes Fbw7. Monoallelic deletion of Usp28 maintains stable Fbw7 but destabilizes Fbw7 substrates. In contrast, complete knockout of Usp28 promotes Pin1-dependent autocatalytic turnover of Fbw7, accumulation of Fbw7 substrates and oncogenic transformation. Overexpression of Usp28 stabilizes both Fbw7 and its substrates and similarly enhances transformation. We propose that dual regulation of Fbw7 activity by Usp28 maintains physiological levels of Fbw7 substrates, and that both loss and overexpression of Usp28 in human cancer promote Fbw7 substrate accumulation. RNAseq experiments of E13.5 murine embryonic fibroblasts (MEFs) derived from animals in which Usp28 was either deleted (-/-), wildtype (+/+) or heterozygous (+/-). In a first set of experiments immortalized MEFs of all three genotypes were analysed in biological triplicates. In a second set of experiments immortalized and Ras transformed MEFs of all three genotypes and MEFs which overexpress USP28 (+/+/+) where sequenced in duplicates.

2015-05-01 | E-GEOD-59354 | biostudies-arrayexpress

Dual targeting of EZH2 and Histone Deacetylases in hematological malignancies promotes transcriptional and metabolic deregulation leading to ferroptosis. [ChIP-Seq]

Project description:The methyltransferase EZH2 functions as the enzymatic component of the PRC2 complex, which deposits methyl groups on H3K27, leading to chromatin condensation and gene repression. Recent studies have shown that EZH2 can also act as a transcriptional modulator outside of the PRC2 complex independent of its methyltransferase activity. In this study, we first aimed to investigate the effects of EZH2 enzymatic inhibition versus protein degradation. We demonstrate that EZH2 degradation is more effective in blocking cellular proliferation compared to EZH2 enzymatic inhibition, and that EZH2 targeting upregulates the cholesterol biosynthesis pathway. Combined targeting of EZH2 and HDACs showed synergistic effects in a broader spectrum of hematological malignancies. Mechanistically, combined targeting of EZH2 and HDACs induced increased levels of H3K27 acetylation and strong upregulation of cholesterol biosynthesis. This leads to metabolic stress due to acetyl-CoA depletion, ultimately inducing ferroptotic cell death.

2024-07-01 | GSE254724 | GEO

Dual targeting of EZH2 and Histone Deacetylases in hematological malignancies promotes transcriptional and metabolic deregulation leading to ferroptosis. [RNA-Seq]

2024-07-01 | GSE254719 | GEO

Loss of Fbxw7 triggers mammary tumorigenesis associated with E2F/c-Myc activation and Trp53 mutation

Project description:Fbw7 is a tumor suppressor protein that regulates the degradation of a multitude of oncogenic substrates, such as c-Jun, c-Myc, Notch1 intracellular domain, and cyclin E. Loss of FBXW7 expression is relatively common in breast cancer. Despite this, the effect of FBXW7 loss on breast tumorigenesis has not been examined. We demonstrate here that loss of FBXW7 is sufficient for breast tumorigenesis. Many of Fbw7’s substrates are transcription factors or are closely linked to transcription factor pathways. As loss of Fbw7 results in upregulation of multiple substrates, we set out to determine which, if any of these transcription factor pathways predominate early after Fbw7 loss and after tumorigenesis. To address this, we employed genome-wide RNA sequencing to examine transcription factor pathway alterations early after FBXW7 loss in non-tumor breast epithelial cells as well as after prolonged FBXW7 loss, in tumor samples. We demonstrate an early upregulation of E2F and c-Myc pathways that is reinforced upon tumorigenesis. These findings suggest E2F and c-Myc as important targetable pathways in Fbw7 low breast cancer patients.

2020-07-15 | GSE144690 | GEO

Expression data from Em-Myc mouse lymphomas

Project description:Ezh2 encodes for the catalyc unit of the PRC2 complex. RNAi-mediated suppressing of Ezh2 by two independent shRNAs promotes Em-myc lymphomagenesis in vivo. Microarray were used to explore the trascriptional changes driven by suppression of Ezh2 in Em-myc cells and to identify which programs contribute to promotion of lymphoma formation. RNA was extracted from purified primary lymphoma cells for each shRNAs targeting Ezh2 and from two independent preparations of premalignant Em-myc cells. Mouse Genome 1.0 ST arrays were processed according to the manifacturer`s instructions.

2015-02-01 | E-GEOD-64537 | biostudies-arrayexpress

Aberrant MYCN expression drives oncogenic hijacking of EZH2 as a transcriptional activator in peripheral T cell lymphoma [ChIP-seq]

Project description:Peripheral T cell lymphoma (PTCL) is a heterogeneous group of hematological cancers arising from the malignant transformation of mature T cells. In a cohort of 28 PTCL cases, we identified recurrent overexpression of MYCN, a member of the MYC family of oncogenic transcription factors. Approximately half of all PTCL cases was characterized by a MYC expression signature. Inducible expression of MYCN in lymphoid cells in a mouse model caused T cell lymphoma that recapitulated human PTCL with a MYC expression signature. Integration of mouse and human expression data identified EZH2 as a key downstream target of MYCN. Remarkably, EZH2 was found to be an essential co-factor for the transcriptional activation of the MYCN-driven gene expression program, which was independent of methyltransferase activity, but dependent on phosphorylation by CDK1. MYCN-driven T cell lymphoma was sensitive to EZH2 degradation or CDK1 inhibition, which displayed synergy with FDA-approved HDAC inhibitors.

2022-09-01 | GSE198125 | GEO

Aberrant MYCN expression drives oncogenic hijacking of EZH2 as a transcriptional activator in peripheral T cell lymphoma [RNA-seq]

2022-09-01 | GSE198124 | GEO

GSI, Human T-ALL

Project description:The NOTCH signaling cascade, which is deregulated in T-cell acute lymphoblastic leukemia (T-ALL) and many other human cancers, offers an attractive target for molecular therapy. One approach employs gamma-secretase inhibitors (GSIs) to suppress production of the intracellular form of NOTCH (NICD), leading to cell growth arrest and apoptosis. Here we show that missense mutations or homozygous deletion of FBW7, which encodes a ubiquitin ligase that targets the NICD for destruction, mediate constitutive NICD expression. FBW7 mutations target key arginine residues needed for binding to the NICD. Although the mutant forms of Fbw7 still bind to MYC, they do not target MYC for degradation, suggesting that stabilization of both NICD and MYC may contribute to transformation in leukemias with mutations in FBW7. Leukemias with FBW7 mutations are resistant to the growth suppressive and apoptotic effects of the MRK-003 GSI. In some resistant lines that express the NICD, this resistance is accompanied by sustained mRNA levels of the NOTCH target DELTEX1 as well as MYC mRNA and protein, implying that residual NICD activity due to the mutant FBW7 can contribute to GSI resistance. Keywords: T-ALL, gamma-secretase, GSI, cell line comparison, FBW7 mutation

2007-08-06 | GSE8416 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data