| abstract |
Provided are: a peptide which contains the BIG3 polypeptide-binding site in PHB2 polypeptide and inhibits the binding of PHB2 polypeptide to BIG3 polypeptide; and a pharmaceutical composition comprising this peptide. The peptide according to the present invention is capable of binding to not PHB2, which is expressed in human systemic organs, but BIG3, which is a protein highly expressed specifically in estrogen receptor-positive cancers, and has an excellent growth inhibitory effect on BIG3-positive cancer cells. Therefore, the peptide according to the present invention is useful as a therapeutic agent for breast cancer which can avoid the occurrence of side effects. |