To examine the effects of sudemycin D6 on haematopoietic cells expressing mutant U2AF1, we generated K562 human erythroleukaemia and OCI-AML3 AML cell lines that have stably integrated doxycycline-inducible, FLAG-tagged U2AF1(S34F) or FLAG-tagged U2AF1(WT) to control for U2AF1 overexpression (Supplementary Fig. 2a,b for K562; Fig. 2c,d for OCI-AML3). The gene discussed is RUNX2; the disease is acute myeloid leukemia.