To test if VASP knockdown suppressed ECM-mediated β1-integrin activation thereby reducing p–FAK levels, we collected cancer spheroids and performed double immunofluorescence (IF) using anti–VASP and Huts-4 antibody selectively recognizing β1-integrin in an active conformation.25 In HCT116, KM12L4, and L3.6 cell lines, VASP and Huts-4 colocalized at the outer cellular layers of the spheroids (IF images of two cell lines are shown in Fig. 3a and another in Suppl. This evidence concerns the gene VASP and cancer.