Moreover, we demonstrated that WDR5 regulated the cell cycle mainly by directly activating the transcription of cyclin E1, cyclin E2, cyclin B1 and UHMK1, whereas WDR5 promoted self-renewal by activating Nanog, WDR5 enhanced chemoresistance via mediating MCL1 and BIRC3 in bladder cancer cells by H3K4me3. The gene discussed is BIRC3; the disease is urinary bladder carcinoma.