title: Sonocatalytic injury of cancer cells attached on the surface of a nickel-titanium dioxide alloy plate.
abstract: The present study demonstrates ultrasound-induced cell injury using a nickel-titanium dioxide (Ni-TiO2) alloy plate as a sonocatalyst and a cell culture surface. Ultrasound irradiation of cell-free Ni-TiO2 alloy plates with 1 MHz ultrasound at 0.5 W/cm(2) for 30s led to an increased generation of hydroxyl (OH) radicals compared to nickel-titanium (Ni-Ti) control alloy plates with and without ultrasound irradiation. When human breast cancer cells (MCF-7 cells) cultured on the Ni-TiO2 alloy plates were irradiated with 1 MHz ultrasound at 0.5 W/cm(2) for 30s and then incubated for 48 h, cell density on the alloy plate was reduced to approximately 50% of the controls on the Ni-Ti alloy plates with and without ultrasound irradiation. These results indicate the injury of MCF-7 cells following sonocatalytic OH radical generation by Ni-TiO2. Further experiments demonstrated cell shrinkage and chromatin condensation after ultrasound irradiation of MCF-7 cells attached on the Ni-TiO2 alloy plates, indicating induction of apoptosis.
authors.affiliation: Institute for Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Ninomiya
authors.affiliation: Faculty of Natural System, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Maruyama
authors.affiliation: Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe 657-8501, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Ogino
authors.affiliation: Faculty of Natural System, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. Electronic address: ktkenji@staff.kanazawa-u.ac.jp.
authors.forename: Kenji
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Institute of Nature and Environmental Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. Electronic address: nshimizu@staff.kanazawa-u.ac.jp.
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Shimizu
mesh_terms: D000497:Alloys / Q000737:chemistry* / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002384:Catalysis; D006801:Humans; D017665:Hydroxyl Radical / Q000378:metabolism; D061986:MCF-7 Cells; D009532:Nickel / Q000737:chemistry*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D000069453:Ultrasonic Waves
chemical_list: D000497:Alloys; C009495:titanium dioxide; D017665:Hydroxyl Radical; D009532:Nickel; D014025:Titanium
keywords: Cancer cells; Nickel–titanium alloy plate; Sonocatalytic reaction; Titanium dioxide; Ultrasound