title: Inhibitory effects of OK-432 (Picibanil) on cellular proliferation and adhesive capacity of breast carcinoma cells.
abstract: We investigated the potent inhibitory effects of OK-432 (Picibanil) on both cellular adhesion and cell proliferation of estrogen-dependent (MCF-7) or estrogen-independent (MDA-MB-231) breast carcinoma cells. Cellular proliferation of both MCF-7 and MDA-MB-231 cells was markedly inhibited in a dose-dependent manner, when the carcinoma cells were exposed to OK-432. Cell attachment assay demonstrated that incubation with OK-432 for 24 h reduced integrin-mediated cellular adhesion of both cell types. However, fluorescence activated cell sorter (FACS) analysis revealed that incubation with OK-432 for 24 h did not decrease the cell surface expressions of any integrins. These results suggest that the binding avidity of integrins is reduced by OK-432 without alteration of the integrin expression. We conclude that OK-432 inhibits integrin-mediated cellular adhesion as well as cell proliferation of breast carcinoma cells regardless of estrogen-dependence, and that these actions of OK-432 contribute to prevention or inhibition of breast carcinoma invasion and metastasis.
authors.affiliation: Department of Thoracic and Visceral Organ Surgery, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan. y.horii@jcom.home.ne.jp
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Horii
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Iino
authors.forename: Michio
authors.initials: M
authors.lastname: Maemura
authors.forename: Jun
authors.initials: J
authors.lastname: Horiguchi
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Morishita
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000188:drug therapy*; D002448:Cell Adhesion / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D004967:Estrogens / Q000494:pharmacology; D005260:Female; D006801:Humans; D009376:Neoplasms, Hormone-Dependent / Q000188:drug therapy*; D010844:Picibanil / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D004967:Estrogens; D010844:Picibanil