The regulatory mechanisms and functional roles of the Hippo signaling pathway in breast cancer.

Hippo signaling pathway has attracted broad attention due to its essential roles in controlling organ size and tumorigenesis. TAZ/YAP, two core downstream molecules of the Hippo signaling pathway in mammals, are tightly regulated by a wide range of extracellular and intrinsic signals in both Hippo signaling pathway-dependent and -independent manners. Besides their roles in the development and function of normal mammary glands, TAZ/YAP display remarkable potency and relevance to multiple aspects of human breast carcinogenesis, including cellular proliferation, differentiation, apoptosis, migration, invasion, epithelial-mesenchymal transition and stemness. In this review, we summarize the regulators of TAZ/YAP, discuss the significant contribution of the Hippo signaling pathway to human breast cancers and highlight their potential therapeutic roles.