YAP1 and breast carcinoma: Accordingly, inhibition of Fascin1 reduced YAP/TAZ transcriptional activity measured by the established 8XGTIIC-lux luciferase reporter assay in MDA-MB-231 breast cancer cells (Fig. 1f), which display high level of YAP/TAZ activity10,48, and whose metastatic ability depends on Fascin47.