Mechanistically, we noticed that high-dose Dox specifically increased the expression levels of phosphorylated AMPK (p-AMPK), p-ULK1 (555) and p-ULK1 (757) to activate AMPK-ULK1 signal pathway in DR-BC cells, instead of DS-BC cells, suggesting that AMPK-ULK1 pathway was susceptible to be activated by Dox in DR-BC cells. Here, ULK1 is linked to breast cancer.