The present invention provides a decoy peptide or polypeptide capable of inhibiting the binding of AMIGO2 and 3-phosphoinositide-dependent kinase 1 (PDK1), and a pharmaceutical composition, containing the decoy peptide or polypeptide as an active ingredient, for preventing or treating cancer or an angiogenic disease. Furthermore, the present invention provides a method for screening a material for preventing or treating cancer or an angiogenic disease. According to the present invention, it is worth noting that the decoy peptide or polypeptide of the present invention induces apoptosis through the inhibition of the binding of AMIGO2 and 3-phosphoinositide-dependent kinase 1 (PDK1) reduces migration and adhesion of endothelial cells significantly reduces vascular induction, survival, and growth. The decoy peptide or polypeptide of the present invention can contribute to the prevention or treatment of cancer or an angiogenic disease through the inhibition of Akt signaling, resulting from the inhibition of a direct interaction of the cytosolic domain of AMIGO2 and the PH domain of PDK1.
