In fact, despite intact (or increased) BRD4 binding at promoter-proximal and gene body in these cells (Figures S3A and S3B), JQ1 treatment had no additional effect on downregulating the BRD4-target genes XBP1 and TCF7 in CHMP5-deficient T-ALL cells (Figure 3I). Here, XBP1 is linked to acute lymphoblastic leukemia.