ESR1 and breast cancer: E4 (10−9 M-10−7 M) also controlled ER + breast cancer cell (T47D) migration and invasion in a dose-dependent manner, through remodeling of the actin cytoskeleton via phosphorylation of moesin (Thr558); however, the pro-migratory effect of E4 was much lower than that of E2 [67].