Next, we used migration and invasion assays to verify whether the pro-metastatic ability of FYN-induced GC cells was mediated by TOPK, and the results showed that the metastatic ability of cells in the OE-FYN group was significantly enhanced compared with the PCMV group, while the addition of TOPK inhibitor OTS514 reversed this phenomenon (Fig. 5E). This evidence concerns the gene PBK and gastric cancer.