YAP1 and breast cancer: Importantly, the following evidence supports this conclusion: (1) VGLL4 gene expression was predictive of survival outcome of patients with breast cancer; (2) VGLL4 regulates several hallmarks of cancer - serving a critical function to inhibit cancer cell proliferation and survival in vitro and tumor growth in vivo; (3) overexpression of VGLL4 led to reduced migration and invasion potential suggesting that VGLL4 suppresses aggressive cancer behavior; (4) VGLL4 induces its anticancer inhibitory activity and its direct antitumor effects by selective modulation of YAP-dependent transcription.