To determine whether C/EBPβ-mediated cisplatin resistance was dependent on the effect of C/EBPβ in regulating H3K79 methylation, we inhibited DOT1L expression by transfecting DOT1L shRNAs into tumor cells or blocked DOT1L activity using the small-molecule inhibitors SGC0946 and EPZ00477734. This evidence concerns the gene CEBPB and neoplasm.