title: Relative biological effectiveness of accelerated heavy ions for induction of morphological transformation in Syrian hamster embryo cells.
abstract: Syrian hamster embryo cells were used to study the morphological transformation induced by accelerated heavy ions with different linear energy transfer (LET) ranging from 13 to 400 keV/micron. Exponentially growing cells were irradiated with 12C or 28Si ion beams generated by the Heavy Ion Medical Accelerator in Chiba (HIMAC), then inoculated to culture dishes. Morphologically altered colonies were scored as transformants. Over the LET range examined, the frequency of transformation induced by the heavy ions increased sharply at very low doses no greater than 5 cGy. The relative biological effectiveness (RBE) of the heavy ions relative to X-rays first increased with LET, reached a maximum value of about 7 at 100 keV/micron, then decreased with the further increase of LET. Our findings confirmed that high LET heavy ions are much more effective than X-rays for the induction of in vitro cell transformation.
authors.affiliation: Radiation Biology Center, Kyoto University, Japan. mikenaga@house.rbc.kyoto-u.ac.jp
authors.forename: Z B
authors.initials: ZB
authors.lastname: Han
authors.forename: H
authors.initials: H
authors.lastname: Suzuki
authors.forename: F
authors.initials: F
authors.lastname: Suzuki
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.forename: Y
authors.initials: Y
authors.lastname: Furusawa
authors.forename: T
authors.initials: T
authors.lastname: Kato
authors.forename: M
authors.initials: M
authors.lastname: Ikenaga
mesh_terms: D000818:Animals; D002244:Carbon; D002470:Cell Survival / Q000528:radiation effects; D002471:Cell Transformation, Neoplastic / Q000528:radiation effects*; D002478:Cells, Cultured; D006224:Cricetinae; D004622:Embryo, Mammalian; D018499:Linear Energy Transfer; D008647:Mesocricetus; D012062:Relative Biological Effectiveness; D012825:Silicon; D014965:X-Rays
chemical_list: D002244:Carbon; D012825:Silicon