AFDN and acute myeloid leukemia: To determine whether ZNF521 is functionally important in MLL-rearranged AML, we first examined the effects of ZNF521 knockdown on the cell proliferation using a panel of human MLL-rearranged AML cell lines, including, THP-1, NOMO-1 (both expressing MLL-AF9), ML-2 (expressing MLL-AF6) and OCI-AML4 (expressing MLL-ENL).