TET1 and leukemia: To find out whether mitoxantrone is capable of triggering cancer cell death in a TET-dependent manner, we generated four human leukemia cell lines (MOLM-14, KG-1, HEL92.1.7, and U937) with TET triple knockdown (TKD) by transducing them with lentiviruses expressing shRNAs against TET1, TET2, and TET3.