Ex vivo treatment of leukemic cells (LCs) from BM of mice with LSK derived, MLL-AF9 driven AML (LCLSK_MLL-AF9; EVI1high) with atRA augmented the abundance and quiescence of LSCe, and the activity of LSCs as determined by serial replating and in vivo limiting dilution assays [17]. Here, KMT2A is linked to acute myeloid leukemia.