Cellular response to fludarabine treatment in combination with different ionizing radiation in renal carcinoma 786-O cells
Song Lei,Liu Yong,Ma Weilin, Chen Linlin,Guo Zhong
Department of Medical Function (Song L,Guo ZH),Department of Biochemistry (Liu Y),Department of Clinical Medicine (Ma WL),Department of Nursing (Chen LL),Medical College of Northwest University for Nationalities,Lanzhou 730030,China
Objective To investigate DNA double-strand breaks and radiosensitization in renalcarcinoma 786-O cells induced by fludarabine (FA) combined with different ionizing radiations. Methods The 786-O cells were exposed to FA combined with X-ray or heavy ion beam irradiation. Flow cytometry was used to evaluate the percentage of γH2AX-positive cells and cell cycle. The neutral comet assay was used to detect DNA double-strand breaks. The colony-forming assay was used to evaluate the effects of different treatments on cell survival. Comparison between groups was made by one-way analysis of variance or Dunnet’s t test. Results Compared with FA alone or irradiation alone, FA combined with different ionizing radiations increased DNA double-strand breaks as shown by significantly increased levels of γH2AX (P=0.007,0.001);FA combined with heavy ion beam irradiation lead to a cell cycle block at the radiosensitive G2/M phase and significantly increased the expression of γH2AX in the G2/M phase (P=0.000,0.000);the neutral comet assay revealed that FA combined with irradiation significantly increased DNA sublethal damage (P=0.020,0.060);FA significantly reduced the colony-forming rate after irradiation (P=0.000,0.030;0.001,0.040). Conclusions FA enhances the effects induced by X-ray and heavy ion beam irradiation with different properties. Particularly, FA substantially enhances the cell death induced by heavy ion beam irradiation.
Song Lei,Liu Yong,Ma Weilin et al. Cellular response to fludarabine treatment in combination with different ionizing radiation in renal carcinoma 786-O cells[J]. Chinese Journal of Radiation Oncology, 2016, 25(6): 646-651.
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2016, Vol. 25 
