FIS1 and neoplasm: In the established gastric tumour mouse models, we found that PX‐478 reduced tumour size (average tumour size: 14.65 mm in SGC7901 xenograft mouse models without PX‐478 vs. 8.45 mm in those with PX‐478) and tumour weight (5.25% in SGC7901 xenograft mouse models without PX‐478 vs. 2.82% in those with PX‐478) (Figures 2F and S2C), and PX‐478 repressed the expression of Drp1 and blocked the interaction between Drp1 and Fis1 in mitochondria (Figures 2G–H).