In contrast, treatment with mDivi‐1, a dynamin inhibitor that blocks mitochondrial fission, suppressed the increase in ΔΨm observed in stem‐like tumor spheres formed by MHCC‐97HYY2KO cells (Figure 4L; Figure S8D–F, Supporting Information), suggesting that YY2 prevented mitochondrial fission. This evidence concerns the gene DNM1 and neoplasm.