YAP1 and cancer: Figure 2 displays the Hippo on and off pathway in cancer. Three more core molecules are phosphorylated by Mst1 in mammals. Mst1 phosphorylates Lats1 on the hydrophobic motif and activation loop and may involve auto-phosphorylation (Zhao et al., 2008). The shifting of the cytoplasm-nucleus is important in cell growth regulation in response to density and cell-to-cell contact. The nuclear translocation of YAP/TAZ caused by the inactivation of the Hippo signaling system promoted cell proliferation, suppressed cell apoptosis, and ultimately resulted in cancer (Dong et al., 2019).