YAP1 and cancer: Very interestingly, unlike the downregulation of TAp63 to promote stem cell proportion, ΔNp63 acts like an oncotarget promoter to enhance cell proliferation, directly interacts with the Hippo effector YAP1, and is a mediator of YAP1 function to promote cancer cell spheroid formation, invasion, migration, and enhance cancer stem cell survival (127, 128).