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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

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

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| EGAS00001002920 | EGA

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

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