To further verify the role of USP15 in metastasis and invasion of breast cancer cells, we then selected four breast cancer cells, MDA-MB-231, BT549, T47D, and MCF-7, for the assay of cell scraping and found that there was an increase in the concentration and dose of PR619 significantly inhibited the ability to migrate of breast cancer cells (Figure 5(b)) In tumor cells, tumor cell extended pseudopodia represent tumor cell motility. This evidence concerns the gene USP15 and breast cancer.