RUNX1-ETO induction rapidly alters chromatin landscape and growth of a specific sub-population of hESC-derived myeloid precursor cells by interfering with RUNX1 regulation
Acute myeloid leukemia is a hematopoietic malignancy caused by recurrent mutations in genes encoding transcriptional, epigenetic and/or signaling regulators. The t(8;21) translocation generates the aberrant transcription factor RUNX1-ETO whose expression can be detected in utero but is insufficient to cause overt disease. Although patients harboring cells with the t(8;21) translocation have acquired additional mutations and show extensive epigenetic reprogramming, the effects directly attributable to RUNX1-ETO expression are unclear. To address this question, we used a human embryonic stem cell differentiation system capable of forming definitive human myeloid progenitor cells to express RUNX1-ETO in an inducible fashion. Induction of RUNX1-ETO causes extensive chromatin reprogramming by interfering with RUNX1 binding, blocks differentiation and arrests cellular growth, whereby growth arrest is reversible following RUNX1-ETO removal. Single cell gene expression analyses show that RUNX1-ETO induction alters the differentiation of a defined sub-population of progenitors, indicating that oncoprotein-mediated transcriptional reprogramming is highly target cell specific.