TOP1 and colorectal cancer: The possible reasons might include: 1 It was reported that in colorectal cancer the TOP1 inhibitor could induce autophagy and reduce apoptosis by activating the AMPK-TSC2-mTOR pathway [40]; Besides, topotecan could induce cytoprotective autophagy in wild-type TP53 colon cancer cells while not in TP53 mutanted or knockout cells [41].