Depletion of ERRα in the breast cancer line MDA-MB231 cause MAP4K4 up-regulation, increased phosphorylation of the ERM protein moesin and aberrant FA formation with concomitantly reduced adhesion to collagen I. Consistent with the regulatory function of MAP4K4 in integrin activation and adhesion (6, 20), pharmacological inhibition of MAP4K4 with PF-06260933 rescued adhesion in ERRα-depleted MDA-MB231 cells. Here, MAP4K4 is linked to breast cancer.