Inhibition of autophagy in dormant metastatic breast cancer cells by silencing ATG7 or administering hydroxychloroquine (HCQ; an autophagy inhibitor) induces mitochondrial dysfunction by reducing mitophagy; this elevates ROS levels and reduces dormant tumor cell survival, thereby suppressing a switch from dormant status to proliferation status [71]. This evidence concerns the gene ATG7 and breast cancer.