Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Sasaki, Ichiro; Hanaoka, Hirofumi*; Yamada, Keiichi*; Watanabe, Shigeki; Sugo, Yumi; Ohshima, Yasuhiro; Ishioka, Noriko
no journal, ,
no abstracts in English
Ikeda, Hiroko; Yokota, Yuichiro; Funayama, Tomoo; Kanai, Tatsuaki*; Nakano, Takashi*; Kobayashi, Yasuhiko
no journal, ,
In this study, human lung normal fibroblasts WI-38 and human lung cancer cells H1299/wt were used. Cells were irradiated with carbon-ion broad beams, then survival rates of bystander cells after co-culture with irradiated cells were measured using colony assay. The survival rates of non-irradiated bystander cancer cells co-cultured with 0.13 Gy irradiated normal cells increased after 6-hours co-culture. On the other hand, the bystander cells co-cultured with 0.5 Gy irradiated normal cells showed decreased survival rates. These results indicated that the bystander responses of the cancer cells changes according to the irradiation dose on the normal cells. In addition, the survival rates of bystander cancer cells showed a tendency to increase by the addition of Carboxy-PTIO to the co-culture medium, when co-cultured with 0.5 Gy irradiated normal cells. From these results, reduction of survival rates is likely to be caused by NO radical as a mediator in bystander effects.
Ikeda, Hiroko; Yokota, Yuichiro; Funayama, Tomoo; Kanai, Tatsuaki*; Nakano, Takashi*; Kobayashi, Yasuhiko
no journal, ,
There have been some reports on bystander effects induced by proton microbeam in contact co-cultured different type cells, but there are few reports using heavy-ion microbeam. So, we have established a new contact co-culture system between human lung normal fibroblast cell line WI-38 and human lung cancer cell line H1299/wt in the same dish. We have also adapted patterning irradiation systems which automatically irradiated to cancer cells (or normal cells) in a certain range by making use of the target cell irradiation technique at JAEA-Takasaki. Thereby, we were able to successively irradiate to 250 sites of confluent cancer area (lengthwise: 5 mm) so as not to overlap the irradiated range, using carbon-ion microbeam collimated by aperture of 20 m. Now, we are analyzing DNA damage and repair of patterning irradiation samples by evaluating focus numbers of immunostained 53BP1 and -H2AX. The details of the method and findings will be reported in the talk.