Two assumptions have been put forward to explain this phenomenon: One is that Notch signaling up-regulates the level of YAP at the transcriptional level, and the up-regulated YAP up-regulates Notch signaling by up-regulating Notch ligands and transcription factors (97); The second is that YAP/TAZ maintains the undifferentiated state by cis-inhibiting Notch signaling and induces the proliferation of adjacent tumor cells by transactivating Notch signaling (11). Here, YAP1 is linked to neoplasm.