Biological Effects of H1299 Cells Exposed to ¹²C Ion Beam and X rays

Key words: 
• linear energy transfer /
• radiosensitivity /
• early apoptosis /
• cell cycle arrest /
• p53

Abstract: To provide basic data for heavyion cancer therapy， the biological effects of ionizing radiations with different linear energy transfers (LET) on radiosensitivity， cell cycle alteration and cell early apoptosis in H1299 cells were studied. The cell radiosensitivity was assessed by means of the standard colonyforming assay. The experimental results show that the survival fraction of H1299 cells irradiated with the 12C ions is evidently lower than that in the case of the Xrays. Moreover， compared with the Xrays the G2/M phase arrest and delay degree and the early apoptosis percentage in H1299 cells irradiated with the 12C ions were more prominent with increasing the radiation dose and repairing time. These results suggested that H1299 cells were more sensitive to 12C ion beam than Xrays. Moreover, less dose， few fractionation and longer fractionation interval were applicable to heavy ion therapy for p53 nulltype tumors.