title: A Fluorescent Imaging Probe Based on a Macrocyclic Scaffold That Binds to Cellular EpCAM.
abstract: Here, we report a fluorescent probe based on a macrocyclic peptide scaffold that specifically stains EpCAM-expressing MCF7 cells. The 14-mer macrocyclic peptide binding to the extracellular domain of EpCAM with a dissociation constant in the low nM range (1.7 nM) was discovered using the random non-standard peptide-integrated discovery system. Notably, this probe containing a fluorescence tag is less than 3000 Da in total and able to visualize nearly every live cell under high cell-density conditions, which was not achieved by the conventional mAb staining method. This suggests that the molecular probe based on the compact macrocyclic scaffold has great potentials as an imaging tool for the EpCAM biomarker as well as a delivery vehicle for drug conjugates.
authors.affiliation: Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-8656, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Iwasaki
authors.affiliation: Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-8654, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Goto
authors.affiliation: Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-8654, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Katoh
authors.affiliation: Disease Control and Homeostasis, Graduate School of Medical Sciences, Kanazawa University, 13-1 Takara-Machi, Kanazawa, Ishikawa, 920-8641, Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Yamashita
authors.affiliation: Disease Control and Homeostasis, Graduate School of Medical Sciences, Kanazawa University, 13-1 Takara-Machi, Kanazawa, Ishikawa, 920-8641, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Kaneko
authors.affiliation: Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-8654, Japan. hsuga@chem.s.u-tokyo.ac.jp.|JST, CREST, 7-3-1 Hongo, Bunkyo, Tokyo, 113-0033, Japan. hsuga@chem.s.u-tokyo.ac.jp.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Suga
mesh_terms: D000951:Antigens, Neoplasm / Q000378:metabolism*; D052158:Aptamers, Peptide; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D000071858:Epithelial Cell Adhesion Molecule; D005456:Fluorescent Dyes; D006801:Humans; D061986:MCF-7 Cells; D015335:Molecular Probes; D009369:Neoplasms / Q000175:diagnosis / Q000378:metabolism*; D061848:Optical Imaging; D010456:Peptides, Cyclic; D011485:Protein Binding; D052156:SELEX Aptamer Technique
chemical_list: D000951:Antigens, Neoplasm; D052158:Aptamers, Peptide; D015815:Cell Adhesion Molecules; C499379:EPCAM protein, human; D000071858:Epithelial Cell Adhesion Molecule; D005456:Fluorescent Dyes; D015335:Molecular Probes; D010456:Peptides, Cyclic
keywords: Cancer cell imaging; EpCAM; Fluorescent imaging probe; In vitro selection; Macrocyclic peptide