AFF1 and leukemia: This depleted cell number phenotype in the RUNX1 KD THP-1 cell was similar to that observed in mouse MLL-AF9 and MLL-AF4 cells when treated with RUNX1 shRNA (Goyama et al., 2013; Wilkinson et al., 2013), This similarity indicated that the function of dysregulated RUNX1 in MLL fusion leukemia was likely conserved.