Targeted brachyury degradation disrupts a highly specific autoregulatory program controlling chordoma cell identity [ChIPmentation]
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE153971 | GEO | 2021/02/08
REPOSITORIES: GEO
Similar Datasets
Project description:Chordomas are rare spinal tumors addicted to expression of the developmental transcription factor brachyury. In chordomas, brachyury is super-enhancer associated and preferentially downregulated by pharmacologic transcriptional CDK inhibition, leading to cell death. To understand the underlying basis of this sensitivity, we dissect the brachyury transcription regulatory network and compare the consequences of brachyury degradation with transcriptional CDK inhibition. Brachyury defines the chordoma super-enhancer landscape and autoregulates through binding its super-enhancer, and its locus forms a transcriptional condensate. Transcriptional CDK inhibition and brachyury degradation disrupt brachyury autoregulation, leading to loss of its transcriptional condensate and transcriptional program. Compared with transcriptional CDK inhibition, which globally downregulates transcription, leading to cell death, brachyury degradation is much more selective, inducing senescence and sensitizing cells to anti-apoptotic inhibition. These data suggest that brachyury downregulation is a core tenet of transcriptional CDK inhibition and motivates developing strategies to target brachyury and its autoregulatory feedback loop.
2021-02-08 | GSE153972 | GEO
Project description:Chordoma is a primary bone cancer with no approved therapy. The identification of therapeutic targets in this disease has been challenging due to the infrequent occurrence of clinically actionable somatic mutations in chordoma tumors. Here we describe the discovery of therapeutically targetable chordoma dependencies via genome-scale CRISPR-Cas9 screening and focused small-molecule sensitivity profiling. These systematic approaches reveal that the developmental transcription factor T (brachyury; TBXT) is the top selectively essential gene in chordoma, and that transcriptional cyclin-dependent kinase (CDK) inhibitors targeting CDK7/12/13 and CDK9 potently suppress chordoma cell proliferation. In other cancer types, transcriptional CDK inhibitors have been observed to downregulate highly expressed, enhancer-associated oncogenic transcription factors (TFs). In chordoma, we find that T is associated with a 1.5-Mb region containing “super-enhancers” and is the most highly expressed super-enhancer-associated TF. Strikingly, transcriptional CDK inhibition leads to preferential and concentration-dependent downregulation of cellular brachyury protein levels in all models tested. Together, these data demonstrate small-molecule targeting of brachyury TF addiction in chordoma, identify a mechanism of T gene regulation that underlies this therapeutic strategy and provide a blueprint for applying systematic genetic and chemical screening approaches to discover vulnerabilities in genomically quiet cancers.
2019-01-20 | GSE121845 | GEO
Project description:Chordoma is a primary bone cancer with no approved therapy. The identification of therapeutic targets in this disease has been challenging due to the infrequent occurrence of clinically actionable somatic mutations in chordoma tumors. Here we describe the discovery of therapeutically targetable chordoma dependencies via genome-scale CRISPR-Cas9 screening and focused small-molecule sensitivity profiling. These systematic approaches reveal that the developmental transcription factor T (brachyury; TBXT) is the top selectively essential gene in chordoma, and that transcriptional cyclin-dependent kinase (CDK) inhibitors targeting CDK7/12/13 and CDK9 potently suppress chordoma cell proliferation. In other cancer types, transcriptional CDK inhibitors have been observed to downregulate highly expressed, enhancer-associated oncogenic transcription factors (TFs). In chordoma, we find that T is associated with a 1.5-Mb region containing “super-enhancers” and is the most highly expressed super-enhancer-associated TF. Strikingly, transcriptional CDK inhibition leads to preferential and concentration-dependent downregulation of cellular brachyury protein levels in all models tested. Together, these data demonstrate small-molecule targeting of brachyury TF addiction in chordoma, identify a mechanism of T gene regulation that underlies this therapeutic strategy and provide a blueprint for applying systematic genetic and chemical screening approaches to discover vulnerabilities in genomically quiet cancers.
2019-01-20 | GSE121843 | GEO
Project description:Chordoma is a primary bone cancer with no approved therapy. The identification of therapeutic targets in this disease has been challenging due to the infrequent occurrence of clinically actionable somatic mutations in chordoma tumors. Here we describe the discovery of therapeutically targetable chordoma dependencies via genome-scale CRISPR-Cas9 screening and focused small-molecule sensitivity profiling. These systematic approaches reveal that the developmental transcription factor T (brachyury; TBXT) is the top selectively essential gene in chordoma, and that transcriptional cyclin-dependent kinase (CDK) inhibitors targeting CDK7/12/13 and CDK9 potently suppress chordoma cell proliferation. In other cancer types, transcriptional CDK inhibitors have been observed to downregulate highly expressed, enhancer-associated oncogenic transcription factors (TFs). In chordoma, we find that T is associated with a 1.5-Mb region containing “super-enhancers” and is the most highly expressed super-enhancer-associated TF. Strikingly, transcriptional CDK inhibition leads to preferential and concentration-dependent downregulation of cellular brachyury protein levels in all models tested. Together, these data demonstrate small-molecule targeting of brachyury TF addiction in chordoma, identify a mechanism of T gene regulation that underlies this therapeutic strategy and provide a blueprint for applying systematic genetic and chemical screening approaches to discover vulnerabilities in genomically quiet cancers.
2019-01-20 | GSE109791 | GEO
Project description:Chordoma is a primary bone cancer with no approved therapy. The identification of therapeutic targets in this disease has been challenging due to the infrequent occurrence of clinically actionable somatic mutations in chordoma tumors. Here we describe the discovery of therapeutically targetable chordoma dependencies via genome-scale CRISPR-Cas9 screening and focused small-molecule sensitivity profiling. These systematic approaches reveal that the developmental transcription factor T (brachyury; TBXT) is the top selectively essential gene in chordoma, and that transcriptional cyclin-dependent kinase (CDK) inhibitors targeting CDK7/12/13 and CDK9 potently suppress chordoma cell proliferation. In other cancer types, transcriptional CDK inhibitors have been observed to downregulate highly expressed, enhancer-associated oncogenic transcription factors (TFs). In chordoma, we find that T is associated with a 1.5-Mb region containing “super-enhancers” and is the most highly expressed super-enhancer-associated TF. Strikingly, transcriptional CDK inhibition leads to preferential and concentration-dependent downregulation of cellular brachyury protein levels in all models tested. Together, these data demonstrate small-molecule targeting of brachyury TF addiction in chordoma, identify a mechanism of T gene regulation that underlies this therapeutic strategy and provide a blueprint for applying systematic genetic and chemical screening approaches to discover vulnerabilities in genomically quiet cancers.
2019-01-20 | GSE109785 | GEO
Project description:Bromodomain-containing protein 4 (BRD4) functions as an epigenetic reader and binds to so-called super-enhancer regions of driving oncogenes such as MYC in cancer. We investigated the possibility to target super-enhancer regulated genes in neuroblastoma and in MYCN amplified disease in particular. We used OTX015, the first small-molecule BRD4 inhibitor to enter clinical phase I/II trials in adults, to test the feasibility to specifically target super-enhancer regulated gene-expression in neuroblastoma. BRD4 inhibition lead to significant transcriptional down-regulation of genes that were associated with super-enhancers, supporting the notion that BRD4 preferentially acts at these chromatin sites. BRD4 inhibition not only attenuated MYCN transcription but most significantly affected MYCN-regulated transcriptional programs.
2016-07-03 | E-MTAB-3672 | biostudies-arrayexpress
Project description:Most endogenous retroviruses (ERVs) in mammals are incapable of retrotransposition; therefore, why ERV de-repression is associated with lethality during early development has been a mystery. Here we report that rapid and selective degradation of the TRIM28 heterochromatin adapter protein triggers dissociation of transcriptional condensates from loci encoding super-enhancer -driven pluripotency genes, and their association with transcribed ERV loci in murine embryonic stem cells. Knockdown of ERV RNAs or forced expression of super-enhancer -enriched transcription factors rescued condensate localization at super-enhancers in TRIM28-degraded cells. In a biochemical reconstitution system, ERV RNA facilitated partitioning of RNA Polymerase II, and the Mediator co- activator into phase-separated droplets. In TRIM28 knockout mouse embryos, single-cell RNA-Seq analysis revealed specific depletion of pluripotent lineages. We propose that coding and non-coding nascent RNAs, including those produced by retrotransposons, may facilitate “hijacking” of transcriptional condensates in various developmental and disease contexts.
2022-03-30 | GSE159468 | GEO
Project description:Chordomas are cancers from the axial skeleton presenting immunological hallmarks of unknown significance. In recent years, some clinical trials demonstrated that chordomas can respond to immunotherapy. We present a comprehensive characterisation of immunological features of 76 chordomas through application of a multimodal approach comprising transcriptional profiling, multidimensional immunophenotyping and TCR profiling. Chordomas generally presented an immune “hot” microenvironment in comparison to other sarcomas, as indicated by the immunologic constant of rejection transcriptional signature. We identified two distinct groups of chordomas based on T cell infiltration. The highly infiltrated group was further characterised by high dendritic cell infiltration and the presence of multicellular immune aggregates in tumours, whereas low T cell infiltration was associated with lower overall cell densities of immune and stromal cells. Interestingly, patients with higher T cell infiltration displayed a more pronounced clonal enrichment of the T cell receptor repertoire compared to those with low T cell counts. Furthermore, we observed that the majority of chordomas maintained HLA class I expression. Our findings shed light on the natural immunity against chordomas. Understanding their immune landscape could guide the development and application of immunotherapies in a tailored manner, ultimately leading to an improved clinical outcome for chordoma patients.
2024-01-26 | GSE239531 | GEO
Project description:Purpose:Lung cancer is the leading cause of cancer-related death, and non-small cell lung cancer (NSCLC) accounts for almost 80-85% of all lung cancer cases.The transcriptional factor brachyury has been verified to promote tumor cells migrate, invade and metastasis in various types of tumors, whereas divergent roles of brachyury on cell proliferation have been reported in several types of tumor cells. In this study, we attempted to explore the effect of brachyury on the cell cycle progression and proliferation capability of NSCLC cells. Methods: Firstly, we performed RNA-sequence and ChIP-sequence to explore underlying downstream pathways regulated by brachyury. Cell proliferation and colony formation assays were utilized to detect the effect of brachyury on the proliferation ability of two types of lung NSCLC cells: H460 and Calu-1, which represent different brachyury expression levels. Following Cell cycle and cell apoptosis assays were used to investigate the mechanism by which brachyury promotes NSCLC grow and progression. Results: RNA-sequence and ChIP-sequence (ChIP-seq) showed that one of the vital downstream pathways regulated by brachyury involves in cell cycle progression. Through cell proliferation assays and colony formation assays, we found that inhibition of brachyury could decrease the capability of proliferation in H460 cells. We also found that brachyury overexpression could prevent the transition from G0/G1 to S phase in Calu-1 cells, and brachyury knockdown could decrease the transition of G2/M phase in H460 cells. The cell apoptosis assays showed that inhibition of brachyury could promote apoptosis in H460 cells. Conclusion: In this study we demonstrate that brachyury and downstream target genes together involve in tumor cell cycle regulation by inducing accelerated transition through G2/M, promote tumor cell proliferation and inhibit apoptosis in lung NSCLC H460 cells. Targeting brachyury expression could be developed into a promising avenue for the prevention of lung cancer progression.
2020-07-21 | GSE151171 | GEO
Project description:Purpose:Lung cancer is the leading cause of cancer-related death, and non-small cell lung cancer (NSCLC) accounts for almost 80-85% of all lung cancer cases.The transcriptional factor brachyury has been verified to promote tumor cells migrate, invade and metastasis in various types of tumors, whereas divergent roles of brachyury on cell proliferation have been reported in several types of tumor cells. In this study, we attempted to explore the effect of brachyury on the cell cycle progression and proliferation capability of NSCLC cells. Methods: Firstly, we performed RNA-sequence and ChIP-sequence to explore underlying downstream pathways regulated by brachyury. Cell proliferation and colony formation assays were utilized to detect the effect of brachyury on the proliferation ability of two types of lung NSCLC cells: H460 and Calu-1, which represent different brachyury expression levels. Following Cell cycle and cell apoptosis assays were used to investigate the mechanism by which brachyury promotes NSCLC grow and progression. Results: RNA-sequence and ChIP-sequence (ChIP-seq) showed that one of the vital downstream pathways regulated by brachyury involves in cell cycle progression. Through cell proliferation assays and colony formation assays, we found that inhibition of brachyury could decrease the capability of proliferation in H460 cells. We also found that brachyury overexpression could prevent the transition from G0/G1 to S phase in Calu-1 cells, and brachyury knockdown could decrease the transition of G2/M phase in H460 cells. The cell apoptosis assays showed that inhibition of brachyury could promote apoptosis in H460 cells. Conclusion: In this study we demonstrate that brachyury and downstream target genes together involve in tumor cell cycle regulation by inducing accelerated transition through G2/M, promote tumor cell proliferation and inhibit apoptosis in lung NSCLC H460 cells. Targeting brachyury expression could be developed into a promising avenue for the prevention of lung cancer progression.
2020-07-21 | GSE151170 | GEO