EP300 and neoplasm: MAP30 has been reported to possess strong antitumour activity against many tumour cells, so is α‐MMC.26, 37 Our previous study has shown that MAP30 at a high concentration 2 μmol/L inhibits autophagy through enhancing p300 and induces apoptosis in acute myeloid leukaemia cells.29 In this present study, we demonstrated that MAP30 at only 25 nmol/L could also attenuate HQ‐induced autophagy by increasing the expression of p300, further verified that the autophagy was regulated by p300.