title: Neoplastic cell transformation by heavy ions.
abstract: We have studied the induction of morphological transformation by heavy ions. Golden hamster embryo cells were irradiated with 95 MeV 14N ions (530 keV/microns), 22 MeV 4He ions (36 keV/microns), and 22 MeV 4He ions with a 100-microns Al absorber (77 keV/microns) which were generated by a cyclotron at the Institute of Physical and Chemical Research in Japan. Colonies were considered to contain neoplastically transformed cells when the cells were densely stacked and made a crisscross pattern. It was shown that the induction of transformation was much more effective with 14N and 4He ions than with gamma or X rays. The relative biological effectiveness (RBE) relative to 60Co gamma rays was 3.3 for 14N ions, 2.4 for 4He ions, and 3.3 for 4He ions with a 100-microns Al absorber. The relationship between RBE and linear energy transfer was qualitatively similar for both cell death and transformation.
authors.affiliation: Division of Radiation Biology, School of Medicine, Yokohama City University, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.forename: M
authors.initials: M
authors.lastname: Watanabe
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.forename: K
authors.initials: K
authors.lastname: Nakano
authors.forename: I
authors.initials: I
authors.lastname: Kaneko
mesh_terms: D000818:Animals; D002471:Cell Transformation, Neoplastic / Q000528:radiation effects*; D006224:Cricetinae; D006371:Helium; D066298:In Vitro Techniques; D007477:Ions; D009584:Nitrogen; D010315:Particle Accelerators; D012062:Relative Biological Effectiveness
chemical_list: D007477:Ions; D006371:Helium; D009584:Nitrogen