Project description:Profiling global gene expression in large ALL cohorts, we identified unique over-expression of FLT3 in ZNF384-rearranged ALL, consistently across cases harboring different fusion partners with ZNF384. Mechanistically, we discovered an intergenic enhancer element at the FLT3 locus that is exclusively activated in ZNF384-rearranged ALL, with the enhancer-promoter looping directly mediated by the fusion protein. There was also a striking global enrichment of active enhancers within ZNF384 binding sites across the genome in ZNF384-rearranged ALL cells.
Project description:ZNF384-rearranged fusion oncoproteins (FO) define a subset of lineage ambiguous leukemias, but the mechanistic role of ZNF384 FO in leukemogenesis and lineage ambiguity is poorly understood. Here, using viral expression in mouse and human hematopoietic stem and progenitor cells (HSPCs) and a Ep300-Zfp384 mouse model we show that ZNF384 FO promote hematopoietic expansion, myeloid lineage skewing, and self-renewal. In mouse HSPCs, concomitant lesions such as NRASG12D, were required for fully penetrant leukemia, whereas expression of ZNF384 FO drove development of B/myeloid leukemia in human HSPCs, with sensitivity of human ZNF384r leukemia to FLT3 inhibition in vivo. Mechanistically, ZNF384 FO occupy a subset of predominantly intragenic/enhancer regions with increased histone 3 lysine acetylation suggesting enhancer function. These data define a paradigm for FO-driven lineage ambiguous leukemia, in which expression in HSPCs results in deregulation of lineage-specific genes and hematopoietic skewing, progressing to full leukemic transformation in the presence of proliferative stress.
Project description:RNA-sequencing was performed on Arf-/- pre-B cell expressing either wild-type ZNF384, TAF15-ZNF384, or TCF3-ZNF384. We found that pre-B cells that express ZNF384 fusion proteins have a gene expression profile similar to patients with ZNF384-rearranged leukemia.
Project description:We report the changes in chromatin occupancy between HA-tagged wild-type ZNF384 and the two leukemogenic fusion proteins, TAF15-ZNF384, and TCF3-ZNF384, in Arf-/- pre-B cells. Using ChIP-sequencing we found that 2298 peaks have new or increased binding while 495 peaks have decreased or lost binding of the fusion proteins compared to wild-type ZNF384.
Project description:We report changes in chromatin occupancy dependent on TCF3-ZNF384 splicing isoform usage. The isoform including exon 8, which encodes 2 zinc finger domains, has increased binding near genes important for nomal hematopoiesis. We report no global changes in H3K27Ac upon expression of ZNF384 fusions but 47 loci with increased H3K27Ac.
Project description:RNA-seq of multiple models of ZNF384-rearrangments (transplanted human CD34 cells and transplanted mouse lineage negative cells) to determine differentially expressed genes.
Project description:We report no global changes in H3K27Ac upon expression of ZNF384 fusions but 47 loci with increased H3K27Ac. Therefore we performed HiChIP H3K27Ac to determine if those loci are enhancers. We did not observe any differential looping.