title: Irradiation effect on osteoclastogenesis stimulated by breast cancer cells.
abstract: To examine the effects of carbon ion and gamma ray irradiation on cancer-induced osteoclastogenesis, mouse calvaria MC3T3-E1 cells were cultured with conditioned medium from irradiated and non-irradiated MCF7 human breast cancer cells. The authors examined RANKL and OPG mRNA expression in osteoblastic MC3T3-E1 cells following treatment with conditioned MCF7 medium. Co-cultured MC3T3-E1 and bone marrow cells treated with conditioned medium from irradiated MCF7 cells showed decreased numbers of osteoclasts, assessed using TRAP staining. Conditioned medium from control MCF7 cells elevated the RANKL/OPG mRNA ratio in MC3T3-E1 cells; this effect was suppressed by carbon ion irradiation of the MCF7 cells. These data demonstrate that indirect interactions between breast cancer cells and MC3T3-E1 cells induce osteoclastogenesis in vitro through modulation of RANKL expression and that this process is suppressed by carbon ion irradiation.
authors.affiliation: Department of Oral and Maxillofacial Radiology, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hirsoshima 734-8553, Japan. jiri@hiroshima-u.ac.jp
authors.forename: Masahiko
authors.initials: M
authors.lastname: Sawajiri
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nomura
authors.forename: Samir
authors.initials: S
authors.lastname: Banik
authors.forename: Ryo
authors.initials: R
authors.lastname: Nishikiori
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Sonoda
authors.forename: Keiji
authors.initials: K
authors.lastname: Tanimoto
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001859:Bone Neoplasms / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D002146:Bony Callus / Q000528:radiation effects*; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D002244:Carbon / Q000627:therapeutic use*; D005260:Female; D005720:Gamma Rays / Q000627:therapeutic use*; D005786:Gene Expression Regulation / Q000528:radiation effects; D063193:Heavy Ion Radiotherapy; D006801:Humans; D051379:Mice; D010012:Osteogenesis / Q000528:radiation effects*; D012333:RNA, Messenger / Q000378:metabolism / Q000528:radiation effects; D053246:Receptor Activator of Nuclear Factor-kappa B / Q000378:metabolism / Q000528:radiation effects
chemical_list: D012333:RNA, Messenger; D053246:Receptor Activator of Nuclear Factor-kappa B; D002244:Carbon