As shown in Figure 3a, the mRNA level of STUB1 was downregulated in osteosarcoma tissues compared with that in normal tissues from our RNA‐seq data.[13] Knockout by sgRNA or knockdown by shRNA of STUB1 increased cell viability, migration, and invasion in U2OS, MG63, 143B, or U2OS/MTX300 cells (Figure 3b–f and Figure S3a,b, Supporting Information), whereas overexpression of STUB1 had the opposite effect in these cells (Figure 3g–j). Here, STUB1 is linked to osteosarcoma.