Despite having a greater inhibitory concentration against ATAD2 (3.56 μM-determined using the TR-FRET assay), AM879 exhibited good antiproliferative activity in BC cells with an IC50 value of 2.43 μM and significantly boosted autophagy and apoptosis through PI3K-AKT-mTOR signaling. Here, ATAD2 is linked to breast cancer.