title: Nucleolin on the cell surface as a new molecular target for gastric cancer treatment.
abstract: Nucleolin is an abundant non-ribosomal protein found in nucleolus and a major component of silver-stained nucleolar organizer region (AgNOR), a histopathological marker of cancer which is highly elevated in cancer cells. We recently reported that nucleolin on the cell surface of mouse gastric cancer cells acts as a receptor for tumor necrosis factor-alpha-inducing protein (Tipalpha), a new carcinogenic factor of Helicobacter pylori. In this study, we first examined the localization of nucleolin on cell surface of five gastric cancer cell lines by cell fractionation and flow cytometry: We found that large amounts of nucleolin were present on surface of MKN-45, KATOIII, MKN-74, and AGS cells, with smaller amounts on surface of MKN-1 cells. The membrane fraction of normal epithelial cells of mouse glandular stomach did not contain much nucleolin, suggesting that translocation of nucleolin to the cell surface occurs during carcinogenesis, making for easier binding with Tipalpha. AS1411, a nucleolin targeted DNA aptamer, inhibited growth of gastric cancer cell lines in this order of potency: MKN-45>KATOIII>AGS>MKN-74=MKN-1, associated with induction of S-phase cell cycle arrest. Fluorescein isothiocyanate (FITC)-AS1411 was more rapidly incorporated into MKN-45 and AGS than into MKN-1 cells, based on varying amounts of cell surface nucleolin. We think that AS1411 first binds to nucleolin on the cell surface and that the binding complex is then incorporated into the cells. All results indicate that nucleolin on the cell surface is a new and promising therapeutic target for treatment of gastric cancer.
authors.affiliation: Research Institute for Clinical Oncology, Saitama Cancer Center, Kitaadachigun, Saitama 362-0806, Japan.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Watanabe
authors.forename: Kazuya
authors.initials: K
authors.lastname: Hirano
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takahashi
authors.forename: Kensei
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Beppu
authors.forename: Hirota
authors.initials: H
authors.lastname: Fujiki
authors.forename: Masami
authors.initials: M
authors.lastname: Suganuma
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D052157:Aptamers, Nucleotide; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D001692:Biological Transport; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism* / Q000382:microbiology; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism* / Q000382:microbiology; D019793:Fluorescein / Q000378:metabolism; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism* / Q000382:microbiology; D016480:Helicobacter pylori / Q000378:metabolism / Q000472:pathogenicity; D006801:Humans; D017879:Isothiocyanates / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D009838:Oligodeoxyribonucleotides / Q000494:pharmacology; D010750:Phosphoproteins / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D016196:S Phase / Q000187:drug effects; D013274:Stomach Neoplasms / Q000188:drug therapy / Q000378:metabolism* / Q000382:microbiology; D000097796:Nucleolin
chemical_list: D000970:Antineoplastic Agents; D052157:Aptamers, Nucleotide; D001426:Bacterial Proteins; D019793:Fluorescein; D017879:Isothiocyanates; D009838:Oligodeoxyribonucleotides; D010750:Phosphoproteins; D016601:RNA-Binding Proteins; D011956:Receptors, Cell Surface; D000097796:Nucleolin; C513936:AGRO 100; C505332:Tipalpha protein, Helicobacter pylori