Subtype-selective prenylated isoflavonoids disrupt regulatory drivers of MYCN-amplified cancers
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE245006 | GEO | 2023/10/10
REPOSITORIES: GEO
Similar Datasets
Project description:Loss of heterozygosity (LOH) at 1p36 is a frequent chromosomal event in a broad range of human cancers with increased incidence observed in nervous system malignancies, including neuroblastoma (NBL). MYCN amplification and 1p36 deletions are highly correlated markers of tumor aggressiveness in NBL. While short distal 1p36 losses are associated with single copy MYCN tumors, larger hemizygous 1p deletions correlate with MYCN amplification, suggesting that two tumor suppressor regions exist in 1p36, a distal and proximal region, which have MYCN-independent and dependent roles. To interrogate this, we genome-edited a proximal candidate, Arid1a, a distal candidate, Chd5, and engineered a syntenic 1p36 LOH deletion in primary mouse NCCs, the likely cell of origin for NBL. Chd5 deletions were found to confer most of the pro-tumorigenic functions of 1p36 LOH in cells expressing endogenous Mycn levels. In contrast, reduced tumor latency in Mycn-driven oncogenesis significantly correlated with the loss of Arid1a. Gene expression analysis found that tumors presenting early onset display a Polycomb Repressive Complex 2 (PRC2) signature and an impaired Trp53 signaling pathway signature. Our findings delineate the tumor suppressor functions of 1p36 LOH in NBL and potentially provide critical insights for the constellation of cancers with 1p36 deletion.
2019-11-28 | GSE123142 | GEO
Project description:Loss of heterozygosity (LOH) at 1p36 is a frequent chromosomal event in a broad range of human cancers with increased incidence observed in nervous system malignancies, including neuroblastoma (NBL). MYCN amplification and 1p36 deletions are highly correlated markers of tumor aggressiveness in NBL. While short distal 1p36 losses are associated with single copy MYCN tumors, larger hemizygous 1p deletions correlate with MYCN amplification, suggesting that two tumor suppressor regions exist in 1p36, a distal and proximal region, which have MYCN-independent and dependent roles. To interrogate this, we genome-edited a proximal candidate, Arid1a, a distal candidate, Chd5, and engineered a syntenic 1p36 LOH deletion in primary mouse NCCs, the likely cell of origin for NBL. Chd5 deletions were found to confer most of the pro-tumorigenic functions of 1p36 LOH in cells expressing endogenous Mycn levels. In contrast, reduced tumor latency in Mycn-driven oncogenesis significantly correlated with the loss of Arid1a. Gene expression analysis found that tumors presenting early onset display a Polycomb Repressive Complex 2 (PRC2) signature and an impaired Trp53 signaling pathway signature. Our findings delineate the tumor suppressor functions of 1p36 LOH in NBL and potentially provide critical insights for the constellation of cancers with 1p36 deletion.
2019-12-01 | GSE123281 | GEO
Project description:Neuroblastoma (NBL) is an embryonal cancer of the sympathetic nervous system (SNS) that causes 15% of pediatric cancer deaths. High-risk neuroblastoma is characterized by N-Myc amplification and segmental chromosomal gains and losses. Due to limited disease models, the etiology of neuroblastoma is largely unknown, including both the cell of origin and the majority of oncogenic drivers. We have established a novel system for studying neuroblastoma based on the transformation of neural crest cells (NCCs), the progenitor cells of the SNS, isolated from mouse embryonic day 9.5 trunk neural tube explants. Based on pathology and gene expression analysis, we report the first successful transformation of wild-type NCCs into NBL by enforced expression of N-Myc to generate phenotypically and molecularly accurate tumors that closely model human MYCN-amplified NBL. Using comparative genomic hybridization, we found that NCC-derived neuroblastoma tumors acquired copy number gains and losses that are syntenic to those observed in human MYCN-amplified neuroblastoma including 17q gain, 2p gain and loss of 1p36. When p53-compromised NCCs were transformed with N-Myc we generated primitive neuroectodermal tumors with divergent differentiation including osteosarcoma. These subcutaneous tumors were metastatic to regional lymph nodes, liver and lung. Our novel experimental approach accurately models human neuroblastoma and establishes a new system with potential to study early stages of neuroblastoma oncogenesis, to functionally assess neuroblastoma oncogenic drivers, and to characterize neuroblastoma metastasis.
2017-09-25 | GSE94914 | GEO
Project description:Neuroblastoma (NB) is a paediatric tumor wherein amplification of the oncogenic basic helix-loop-helix (bHLH) transcription factor (TF) MYCN confers clinical and biologic features prototypical of Myc-dependent cancers. TF-dependent cancers like MYCN-amplified NB are difficult to target, but the availability of clinical-candidate transcription inhibitors makes selective blockade of oncogenic TF activity a possibility. Here we investigated whether NB could be controlled via dual targeting of the transcription elongation machinery and cell cycle progression, using an orally bioavailable and selective CDK9/2 inhibitor CYC065. CYC065 blocks nascent transcription and leads to a drastic reduction in steady-state levels of short-lived transcripts. In MYCN-amplified NB, CYC065 rapidly and completely eliminated MYCN mRNA and protein, terminating expression of a MYCN-dependent gene expression programme. This result is phenocopied by multiple clinical-candidate CDK9 chemical inhibitors and genetic manipulation of CDK9. Mechanistically, CYC065 dissociates MYCN from physical proximity of P-TEFb in cells. P-TEFb co-occupies promoters and enhancers of de-differentiating pathway genes highly-occupied by MYCN, and CDK9 inhibition terminates expression of these and other highly transcribed genes. Intriguingly, targeted inhibition of CDK9 alone is insufficient to eradicate MYCN-dependent cells lines as CDK9 loss alone is compensated by upregulation of CDK2. CYC065 targeted MYCN-driven neuroblastoma in vivo, resulted in tumor regression or eradication and prolonged survival in multiple NB models, and was effective against a wide range of Myc-dependent cancer cells lines in vitro. The data establish that combined CDK9/CDK2 inhibition blocks transcriptional dependence induced by MYCN, highlighting a potential clinical strategy by which many Myc-driven cancers could be targeted.
2019-01-01 | GSE107126 | GEO
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
Project description:To study differentially expressed genes in neuro-ectodermal cell lines MYCN amplification (NMA) is the most important prognostic factor in neuroblastoma (NBL) patients, however 70% of advanced stage NBL are non-NMA and lack known driving oncogenic events. Gene expression profiles (HU133plus2.0 arrays, Affymetrix) of 17 NBL and 5 peripheral neuro-ectodermal cell lines were used to identify potential subgroups of NBL cell lines with a distinct gene signature. One group of non-NMA NBL cell lines was identified with a distinct gene expression profile and characterized by high expression of AXL. AXL is a tyrosine kinase receptor which plays a role in the metastatic process of cancer. We hypothesized that AXL contributes to the metastasizing potential of non-NMA NBL and tested if AXL silencing diminishes malignant properties of high AXL expressing cell lines. AXL was silenced in two non-NMA NBL cell lines by using a lentiviral shRNA construct that was able to transduce these cell lines with >90% infection efficiency. AXL mRNA expression level was efficiently knocked-down resulting in a severe decrease of migration of AXL positive cell lines GI-M-EN and SH-EP-2, and decreased invasion of GI-M-EN. Morphologically, AXL knockdown induced more rounded cells with a loss of contact. Intracellularly, we observed induction of stress fibers (immunofluorescence F-actin) in GI-M-EN. These changes in cytoskelet were associated with decreased migration. No effects were observed for cell proliferation, apoptosis or downstream pathways. In conclusion, AXL is identified as a possible mediator of NBL metastasis. Arrays were performed with 5 different PNET cell lines, which were used as controls for 17 NBL cell lines (GSE22771)
2012-01-01 | E-GEOD-33903 | biostudies-arrayexpress
Project description:Deregulated expression of MYC family oncogenes occurs frequently in human cancer and is often associated with aggressive disease and poor prognosis. While MYC is a highly warranted target, it has been considered “undruggable”, and no specific anti-MYC drugs are available in the clinic. We recently identified molecules named MYCMIs that inhibit the interaction between MYC and its essential partner MAX. Here we show that one of these, MYCMI-7, efficiently and selectively inhibits MYC:MAX and MYCN:MAX interactions in cells, binds directly to recombinant MYC and reduces MYC-driven transcription. In addition, MYCMI-7 induces degradation of MYC and MYCN proteins. MYCMI-7 potently induces growth arrest/apoptosis in tumor cells in a MYC/MYCN- dependent manner and downregulates the MYC pathway on a global level as determined by RNA-seq. Sensitivity to MYCMI-7 correlates with MYC expression in a panel of 60 tumor cell lines and MYCMI-7 shows high efficacy towards a collection of patient- derived primary glioblastoma and acute myeloid leukemia (AML) ex vivo cultures. Importantly, a variety of normal cells become G1 arrested without signs of apoptosis upon MYCMI-7 treatment. Finally, in mouse tumor models of MYC-driven AML, breast cancer and MYCN-amplified neuroblastoma, treatment with MYCMI-7 downregulates MYC/MYCN, inhibits tumor growth and prolongs survival through apoptosis with little side effects. In conclusion, MYCMI-7 is a potent and selective MYC inhibitor that is highly relevant for the development into clinically useful drugs for treatment of MYC-driven cancer.
2023-03-08 | GSE197062 | GEO
Project description:To study differentially expressed genes in neuro-ectodermal cell lines MYCN amplification (NMA) is the most important prognostic factor in neuroblastoma (NBL) patients, however 70% of advanced stage NBL are non-NMA and lack known driving oncogenic events. Gene expression profiles (HU133plus2.0 arrays, Affymetrix) of 17 NBL and 5 peripheral neuro-ectodermal cell lines were used to identify potential subgroups of NBL cell lines with a distinct gene signature. One group of non-NMA NBL cell lines was identified with a distinct gene expression profile and characterized by high expression of AXL. AXL is a tyrosine kinase receptor which plays a role in the metastatic process of cancer. We hypothesized that AXL contributes to the metastasizing potential of non-NMA NBL and tested if AXL silencing diminishes malignant properties of high AXL expressing cell lines. AXL was silenced in two non-NMA NBL cell lines by using a lentiviral shRNA construct that was able to transduce these cell lines with >90% infection efficiency. AXL mRNA expression level was efficiently knocked-down resulting in a severe decrease of migration of AXL positive cell lines GI-M-EN and SH-EP-2, and decreased invasion of GI-M-EN. Morphologically, AXL knockdown induced more rounded cells with a loss of contact. Intracellularly, we observed induction of stress fibers (immunofluorescence F-actin) in GI-M-EN. These changes in cytoskelet were associated with decreased migration. No effects were observed for cell proliferation, apoptosis or downstream pathways. In conclusion, AXL is identified as a possible mediator of NBL metastasis.
2012-01-01 | GSE33903 | GEO
Project description:Deregulation of the MYCN gene drives the development of neuronal and neuroendocrine tumors and is often associated with a particularly poor prognosis. Here we show that activation of MYCN in human neuroblastoma cells induces promoter escape of RNAPII. If pause release of RNAPII fails, MYCN recruits the BRCA1 protein to promoter-proximal regions. Recruitment of BRCA1 prevents MYCN-dependent accumulation of stalled RNAPII and enhances transcriptional activation by MYCN. Mechanistically, BRCA1 stabilizes mRNA de-capping complexes and enables MYCN to suppress R-loop formation in promoter-proximal regions. Recruitment of BRCA1 is mediated by the ubiquitin-specific protease, USP11, which binds specifically to MYCN that is de-phosphorylated at Thr58. Thr58 phosphorylation promotes proteasomal turnover of MYCN, hence BRCA1 stabilizes chromatin association of MYCN. Since BRCA1 is highly expressed in neuronal progenitor cells during early development and since MYC is less efficient than MYCN in recruiting BRCA1, our findings argue that a cell lineage-specific stress response enables MYCN-driven tumors to cope with deregulated RNAPII function.
2019-03-21 | GSE111905 | GEO
Project description:MYCN amplification in neuroblastoma leads to aberrant expression of MYCN oncoprotein, which binds active genes promoting transcriptional amplification. Yet how MYCN coordinates transcription elongation to meet productive transcriptional amplification and which elongation machinery represents MYCN-driven vulnerability remain to be identified. We conducted a targeted screen of transcription elongation factors and identified the super elongation complex (SEC) as a unique vulnerability in MYCN-amplified neuroblastomas. MYCN directly binds EAF1 and recruits SEC to enhance processive transcription elongation. Depletion of EAF1 or AFF1/AFF4, another core subunit of SEC, leads to a global reduction in transcription elongation and elicits selective apoptosis of MYCN-amplified neuroblastoma cells. A combination screen reveals SEC inhibition synergistically potentiates the therapeutic efficacies of FDA-approved BCL2 antagonist ABT-199, in part due to suppression of MCL1 expression, both in MYCN-amplified neuroblastoma cells and in patient-derived xenografts. These findings identify disruption of the MYCN-SEC regulatory axis as a promising therapeutic strategy in neuroblastoma.
2023-05-10 | PXD039332 | Pride