Specifically, loss of DLG5 down-regulated and mislocalized Scribble, inhibited the Hippo signaling pathway by decreasing the interaction of Scribble with Mst1 and Lats1, and increased YAP nuclear localization and TEAD transcription, thereby promoting the proliferation of breast epithelial cells and breast cancer cells, inducing EMT, disrupting the maintenance of cell polarity, and increasing cell migration and invasion. The gene discussed is MST1; the disease is breast cancer.