Mitochondrial genotypes and radiation-induced micronucleus formation in human osteosarcoma cells in vitro.
We investigated whether or not the mitochondrial genotypes affect radiation-induced micronucleus (MN) formation. For that purpose, the rho+, KT1 and rho0 human osteosarcoma cell lines were used, which carry the wild-type mitochondrial DNA (mtDNA), the tRNALys mutant mtDNA and no mtDNA, respectively. Despite no significant difference in the clonogenic radiosensitivity, the rho+, KT1 and rho0 cells exhibited high, intermediate and low radiosensitivities, respectively, to the MN induction in cytokinesis-blocked binucleated cells. Such differential MN inductions were correlated with high, intermediate and low levels of cellular ATP in the rho+, KT1 and rho0 cells, respectively, but not exactly with ROS production. Antimycin A that inhibits the respiratory complex III reduced the rate of radiation-induced MN induction in the rho+ and KT1, but not rho0 cells. Thus, the functional status of the mtDNA to produce ATP appears to play a significant role for radiation-induced MN.
Yoshida
K
K
Division of Multidisciplinary Radiotherapy, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871, Japan. kyoshida@onh.go.jp
Yamazaki
H
H
Ozeki
S
S
Inoue
T
T
Yoshioka
Y
Y
Yoneda
M
M
Fujiwara
Y
Y
Inoue
T
T
D000255:Adenosine Triphosphate / Q000378:metabolism; D002455:Cell Division / Q000528:radiation effects; D002467:Cell Nucleus / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D004272:DNA, Mitochondrial / Q000235:genetics*; D004307:Dose-Response Relationship, Radiation; D005434:Flow Cytometry; D005720:Gamma Rays; D005838:Genotype; D006801:Humans; D048629:Micronuclei, Chromosome-Defective / Q000235:genetics / Q000528:radiation effects*; D015162:Micronucleus Tests; D012516:Osteosarcoma / Q000378:metabolism* / Q000473:pathology; D017382:Reactive Oxygen Species / Q000378:metabolism; D013481:Superoxides / Q000032:analysis; D014407:Tumor Cells, Cultured / Q000528:radiation effects*; D014965:X-Rays
D004272:DNA, Mitochondrial; D017382:Reactive Oxygen Species; D013481:Superoxides; D000255:Adenosine Triphosphate