KMT2A and leukemia: Given the correlation between Let-7g and longer disease latencies observed in MLL-GAS7 and MLL-AF1p leukemias, we overexpressed let-7g in MLL-FP cells to test for increased differentiation using a miRNA retroviral vector (MPIE) that co-expresses GFP and examined the myeloid surface marker Cd11b (Figure 6A).