@misc{oai:repo.qst.go.jp:00067421,
 author = {Sagara, Masashi and Ban, Sadayuki and Sudou, Hitomi and Okayasu, Ryuichi and Imai, Takashi and 相良 雅史 and 伴 貞幸 and 須藤 仁美 and 岡安 隆一 and 今井 高志},
 month = {Aug},
 note = {DNA double-strand breaks (DSBs) induced by ionizing radiation represent the most serious damage in cells.  Immediately after the formation of DSB, Ser-139 of histone H2AX is phosphorylated at the site of DSB.  The phosphorylated H2AX (gammaH2AX) foci can be observed with an immunohistochemical staining using anti-gammaH2AX antibody.  It is also known that each gammaH2AX focus corresponds to one DSB and disappears when the DSB is rejoined.  Using this method, we compared the amount of unrejoined DSBs among cell lines with different radiation sensitivities after X irradiation.  At 30 min following 2 Gy of X-rays, the number of foci observed is similar in all cell lines studied.  However, the disappearance of foci in radioresiatant colon cancer cell lines (SW-480 and CaCo-2) was faster than that in radiosensitive ones (SW-48 and LoVo).  At 12 hr after X-irradiation, few foci were observed in SW-480 and CaCo-2 cells, while many foci were remained in SW-48 and LoVo cells. Furthermore, the number of focus disappeared much slower in irradiated radiosensitive AT and 180BR cells as compared to normal human fibroblasts.  Similar results were obtained when cells from radiosensitive LEC rat were compared with cells from Fisher rat.  Our data demonstrate that the rejoining kinetics of DSBs measured by gammaH2AX foci formation correlates with the cellular radiosensitivities., The 12th International Congress of Radiation Research(ICRR)},
 title = {gammaH2AX foci formation in x-irradiated mammalian cell lines with different radio-sensitivities},
 year = {2003}
}