To investigate the possibility of the involvement of AKT signaling during the apoptotic process by FAK inhibition, the level of activated AKT or phosphorylated AKT (pAKT) was analyzed by Western blotting: pAKT at S473 decreased after induction of FAK shRNA in BT-549 cells (Figure 4G), whereas the level of pAKT was minimal at the basal level in MDA-MB-231 cells (Figure 4G), which might explain the specific effect of FAK downregulation only in breast cancer cells with FAK-copy-gain via AKT signaling. Here, PTK2 is linked to breast carcinoma.