YAP1 and breast cancer: Previously, we examined the expression levels of YAP protein in 4 breast cancer cell lines (MCF7, T47D, MDA-MB-231 and MDA-MD-468) and revealed that YAP was overexpressed in MDA-MB-231, MDA-MB-468 and T47D cell lines, while it was relatively low expressed in the MCF7 cell line (data not shown).