Bromodomain and extraterminal proteins foster the core transcriptional regulatory programs and confer vulnerability in liposarcoma (RNA-Seq)

Purpose: Identification of core transcriptional regulatory programs and bromodomain and extraterminal (BET) protein dependency in liposarcoma (LPS) Methods: ChIP-seq and RNA-seq were performed on LPS cells. Antibodies against H3K27ac, H3K4me1, H3K4me3, RNA-Pol2, BRD2, BRD3, BRD4, FOSL2, pan-RUNX, and DDIT3 (FUS-DDIT3) were used for ChIP-seq assays. The transcriptome responses of LPS141 and MLS402 cells to OTX015 and ARV-825 were compared. Result: We generated genome-wide chromatin-state maps of LPS cells. By charting the super-enhancer structures, we identify a bromodomain and extraterminal (BET) protein-cooperated FUS-DDIT3 function in myxoid LPS and a BET protein-dependent core transcriptional regulatory circuitry consisting of FOSL2, MYC, and RUNX1 in de-differentiated LPS. This study also provides a framework for discovering and targeting of core oncogenic transcriptional programs. ChIP-seq and RNA-seq were performed on LPS cells.