Intriguingly, inducing revumenib resistance in the KMT2A::AFF1+ ALL cell line RS4;11 cell line (Figure 4D,E), led to the acquisition of the MEN1 M322T mutation in only one (i.e., RS4;11REV_RES#2) of four revumenib-resistant daughter lines of RS4;11. This evidence concerns the gene AFF1 and acute lymphoblastic leukemia.