title: Relative biological effectiveness of 12C and 28Si radiation in C57BL/6J mice.
abstract: Study of heavy ion radiation-induced effects on mice could provide insight into the human health risks of space radiation exposure. The purpose of the present study is to assess the relative biological effectiveness (RBE) of (12)C and (28)Si ion radiation, which has not been reported previously in the literature. Female C57BL/6J mice (n = 15) were irradiated using 4-8 Gy of (28)Si (300 MeV/nucleon energy; LET 70 keV/μm) and 5-8 Gy of (12)C (290 MeV/nucleon energy; LET 13 keV/μm) ions. Post-exposure, mice were monitored regularly, and their survival observed for 30 days. The LD(50/30) dose (the dose at which 50 % lethality occurred by 30-day post-exposure) was calculated from the survival curve and was used to determine the RBE of (28)Si and (12)C in relation to γ radiation. The LD(50/30) for (28)Si and (12)C ion is 5.17 and 7.34 Gy, respectively, and the RBE in relation to γ radiation (LD(50/30)-7.25 Gy) is 1.4 for (28)Si and 0.99 for (12)C. Determination of RBE of (28)Si and (12)C for survival in mice is not only important for space radiation risk estimate studies, but it also has implications for HZE radiation in cancer therapy.
authors.affiliation: Department of Biochemistry and Molecular & Cell Biology, Lombardi Comprehensive Cancer Center, Georgetown University, Room E504 Research Building, 3970 Reservoir Rd., NW, Washington, DC 20057-1468, USA.
authors.forename: Shubhankar
authors.initials: S
authors.lastname: Suman
authors.forename: Kamal
authors.initials: K
authors.lastname: Datta
authors.forename: Daniela
authors.initials: D
authors.lastname: Trani
authors.forename: Evagelia C
authors.initials: EC
authors.lastname: Laiakis
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Strawn
authors.forename: Albert J
authors.initials: AJ
authors.lastname: Fornace
mesh_terms: D000818:Animals; D002244:Carbon / Q000009:adverse effects*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005720:Gamma Rays / Q000009:adverse effects; D020450:Heavy Ions / Q000009:adverse effects*; D018499:Linear Energy Transfer; D051379:Mice; D008810:Mice, Inbred C57BL; D012062:Relative Biological Effectiveness; D012825:Silicon / Q000009:adverse effects*
chemical_list: D002244:Carbon; D012825:Silicon