title: Basic study on apoptosis induction into cancer cells U-937 and EL-4 by ultrasound exposure.
abstract: Recently, the low invasive cancer treatments with small aftereffects have been considered. We are studying on the suppression methods of cancer cell proliferation with ultrasound. Cancer cells of mouse T lymphoma (EL-4) have been used in our study. The human histitocytic lymphoma cells (U-937) was used in this time. The cancer cells were cultured in a culture medium of RPMI1640. The standing wave acoustic field was formed in a water tank of our ultrasound exposure system by a vibrating plate driven with a Langevine type transducer. The U-937 and EL-4 were exposed to ultrasound in the acoustic field with spatial average acoustic intensity of 350 mW/cm(2) at 150 kHz. The viable rate of EL-4 decreased with the lapse of culture time after ultrasound exposure. U-937 did not show the remarkable decrease tendency. The proliferation of U-937 which exposed to ultrasound with 700 mW/cm(2) was suppressed. It can be thought that apoptosis was induced in the cancer cells in this condition. We observed the morphological change on the U-937 exposed to ultrasound with this condition. The morphological changes by apoptosis like the shrink of cells, formation of apoptotic bodies etc. can be observed with an optical microscope and a phase contrast microscope.
authors.affiliation: Toin University of Yokohama, Faculty of Biomedical Engineering, 1614, Kurogana-cho, Aoba-ku, Yokohama, Kanagawa 225-8502, Japan. shin1@cc.toin.ac.jp <shin1@cc.toin.ac.jp>
authors.forename: Shinichi
authors.initials: S
authors.lastname: Takeuchi
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Udagawa
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Oku
authors.forename: Takuma
authors.initials: T
authors.lastname: Fujii
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nishimura
authors.forename: Norimichi
authors.initials: N
authors.lastname: Kawashima
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000528:radiation effects*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000528:radiation effects*; D048429:Cell Size / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D008223:Lymphoma / Q000473:pathology* / Q000503:physiopathology* / Q000628:therapy; D051379:Mice; D011829:Radiation Dosage; D013045:Species Specificity; D020298:U937 Cells; D014464:Ultrasonic Therapy / Q000379:methods*; D014465:Ultrasonics