YAP1 and breast cancer: In the hippo pathway, loss of the tumor suppressor LATS1 is associated with the development of tumors such as soft tissue sarcoma, ovarian cancer, and breast cancer.54, 55 LATS1 restricts the activity of WW domain‐containing protein YAP/TAZ by phosphorylation and promotes YAP/TAZ degradation to inhibit cell proliferation.