In line with the absence of an enhanced effect by the CBL0137/panobinostat drug combination on histone marks in KMT2A-r leukemia cells, we observed that the drug combination did not change expression levels of HOXA9 and MEIS1 genes, well-described leukemogenic target genes of KMT2A-r fusion proteins and upregulated in many KMT2A-r leukemias downstream of epigenetic modifications driven by KMT2A translocations (Supplementary Figure 10) (22). This evidence concerns the gene MEIS1 and leukemia.