BRD4 and leukemia: To test whether SPOP targets BRD4 and MYC directly to regulate MYC pathways and BETi response in KMT2A-r leukemia cells (34), we conducted total RNA-seq and whole-cell mass spectrometry assays to quantify the RNA and global protein abundance in sgNT- and sgSPOP-targeted cells, with or without ABBV-744 treatment (Fig. 4A and SI Appendix, Table S3).