Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The SS18-SSX fusion oncoprotein hijacks BAF complex targeting and function to drive synovial sarcoma [RNA-Seq Cell]

ABSTRACT: Synovial sarcoma (SS) is defined by the hallmark SS18-SSX fusion oncoprotein, which renders BAF complexes aberrant in two manners: gain of SSX to the SS18 subunit and concomitant loss of BAF47 subunit assembly. Here we demonstrate that SS18-SSX globally hijacks BAF complexes on chromatin to activate a SS transcriptional signature we define using primary tumors and cell lines. Specifically, SS18-SSX retargets BAF complexes from enhancers to broad polycomb domains to oppose PRC2-mediated repression and activate bivalent genes. Upon suppression of SS18-SSX, reassembly of BAF47 restores enhancer activation, but is not required for proliferative arrest. These results establish a global hijacking mechanism for SS18-SSX on chromatin, and define the distinct contributions of two concurrent BAF complex perturbations.

ORGANISM(S): Homo sapiens

PROVIDER: GSE108026 | GEO | 2018/05/31

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

The SS18-SSX fusion oncoprotein hijacks BAF complex targeting and function to drive synovial sarcoma [ChIP-Seq]

Project description:Synovial sarcoma (SS) is defined by the hallmark SS18-SSX fusion oncoprotein, which renders BAF complexes aberrant in two manners: gain of SSX to the SS18 subunit and concomitant loss of BAF47 subunit assembly. Here we demonstrate that SS18-SSX globally hijacks BAF complexes on chromatin to activate a SS transcriptional signature we define using primary tumors and cell lines. Specifically, SS18-SSX retargets BAF complexes from enhancers to broad polycomb domains to oppose PRC2-mediated repression and activate bivalent genes. Upon suppression of SS18-SSX, reassembly of BAF47 restores enhancer activation, but is not required for proliferative arrest. These results establish a global hijacking mechanism for SS18-SSX on chromatin, and define the distinct contributions of two concurrent BAF complex perturbations.

2018-05-31 | GSE108025 | GEO

The SS18-SSX fusion oncoprotein hijacks BAF complex targeting and function to drive synovial sarcoma [ATAC-seq]

2018-05-31 | GSE114487 | GEO

The SS18-SSX fusion oncoprotein hijacks BAF complex targeting and function to drive synovial sarcoma [RNA-Seq Tumor]

2018-05-31 | GSE108027 | GEO

SS18-SSX-mediated hijacking of BAF complexes drives synovial sarcoma

Project description:Synovial sarcoma (SS) is defined by a recurrent t(x;18) chromosomal translocation, which produces the hallmark SS18-SSX oncogenic fusion. Incorporation of SS18-SSX into BAF complexes renders BAF complexes aberrant in two distinct manners: the addition of 78aa of SSX onto SS18, and concomitant loss of BAF47 assembly. However, the importance and functional contributions of each of these perturbations on BAF complex targeting and gene expression regulation remain unclear. Here we use an integrative set of genomic approaches in human cancer cell lines and primary tumor samples to define the mechanistic consequences of the SS18-SSX fusion oncoprotein. We find that SS18-SSX hijacks BAF complexes to broad polycomb domains to activate bivalent genes, driving a unique gene expression program distinct from other loss-of-function BAF complex malignancies. Importantly, restoration of BAF47 rescues enhancer activation but is dispensable for proliferative arrest in cell lines. These results demonstrate that gain-of-function SS18-SSX-mediated BAF complex targeting and gene activation is the driving event in SS, and present a mechanism by which distinct functions of BAF complexes can be co-opted to drive oncogenesis.

| EGAS00001002920 | EGA

ena-DATASET-MDACC-29-05-2018-15:47:46:325-962 - samples

| EGAD00001004135 | EGA

Aberrant gene activation in synovial sarcoma relies on SSX specificity and increased PRC1.1 stability

Project description:The SS18-SSX fusion drives oncogenic transformation in synovial sarcoma by bridging SS18, a member of the mSWI/SNF (BAF) complex, to Polycomb repressive complex 1 (PRC1) target genes. Here we show that the ability of SS18-SSX to occupy H2AK119ub1-rich regions is an intrinsic property of its SSX C terminus, which can be exploited by fusion to transcriptional regulators beyond SS18. Accordingly, SS18-SSX recruitment occurs in a manner that is independent of the core components and catalytic activity of BAF. Alternative SSX fusions are also recruited to H2AK119ub1-rich chromatin and reproduce the expression signatures of SS18-SSX by engaging with transcriptional activators. Variant Polycomb repressive complex 1.1 (PRC1.1) acts as the main depositor of H2AK119ub1 and is therefore required for SS18-SSX occupancy. Importantly, the SSX C terminus not only depends on H2AK119ub1 for localization, but also further increases it by promoting PRC1.1 complex stability. Consequently, high H2AK119ub1 levels are a feature of murine and human synovial sarcomas. These results uncover a critical role for SSX-C in mediating gene deregulation in synovial sarcoma by providing specificity to chromatin and further enabling oncofusion binding by enhancing PRC1.1 stability and H2AK119ub1 deposition.

2023-05-24 | GSE233376 | GEO

Aberrant gene activation in synovial sarcoma relies on SSX specificity and increased PRC1.1 stability

2023-05-24 | GSE233375 | GEO

The SS18-SSX oncoprotein hijacks KDM2B-PRC1.1 to drive synovial sarcoma [RNA-seq]

Project description:Gene fusions arising from chromosomal translocations are key oncogenic drivers in soft tissue sarcomas but little is known about how they exert their oncogenic effects. Our study explores the molecular mechanisms by which the SS18-SSX fusion oncoprotein subverts epigenetic mechanisms of gene regulation to drive synovial sarcoma. Using functional genomics, we identify KDM2B – a histone demethylase and core component of a non-canonical Polycomb Repressive Complex 1 (PRC1.1) – as selectively required for sustaining synovial sarcoma cell transformation. SS18-SSX physically interacts with PRC1.1 and co-associates with SWI/SNF and KDM2B complexes on unmethylated CpG islands genome-wide. Via KDM2B, SS18-SSX binds and aberrantly activates expression of a series of developmentally regulated transcription factors that would otherwise be targets of polycomb-mediated repression, which is restored upon KDM2B depletion leading to irreversible mesenchymal differentiation. Thus, SS18-SSX de-regulates developmental programs to drive transformation by hijacking a transcriptional repressive complex to aberrantly activate gene expression.

2018-03-01 | GSE108928 | GEO

The SS18-SSX oncoprotein hijacks KDM2B-PRC1.1 to drive synovial sarcoma [ATAC-seq]

2018-03-01 | GSE108927 | GEO

The SS18-SSX oncoprotein hijacks KDM2B-PRC1.1 to drive synovial sarcoma [ChIP-seq]

2018-03-01 | GSE108926 | GEO