Previous studies have depicted that activated ERK1/2 phosphorylates p120-catenin through TGF-β action, thereby promoting p120-catenin binding to E3 ubiquitin ligase SMurf1, leading to AJ complex dissociation, TJ dissociation, and cytoskeletal rearrangement of tumor cells, EMT, and promotion of breast cancer metastasis [32]. This evidence concerns the gene MAPK3 and breast cancer.