MST1 and neoplasm: The Hippo signaling pathway is a highly conserved tumor suppressor pathway, mainly including Ste20-like kinase 1 (MST1) and large tumor suppressor 1 (LATS1), Yes associated protein 1 (YAP1) and its analog TAZ, and the regulatory subunits of MST1 and LATS1, MOB1 and SAV1.