Properties of apoptosis and cell cycle in six radiation-induced cell lines

OBJECTIVE:To analysis the apoptosis and cell cycle of 6 radiation-induced cell lines,including HL-7702,HepG2,SMMC-7721,HCI-H460,A549 and Hela.METHODS:After being cultured for 48 hours the 6 cells were irradiated at 4 Gy X-radiation.The cell cycle and apoptosis of cells after being irradiated for 0,6,12,24,36 and 48 hours were detected by FCM.RESULTS:Before being irradiated at 4 Gy X-radiation,the apoptosis rates of SMMC-7721 and HCI-H460 were significantly higher than those of the other 4 cell lines(t=20.98,P0.005).Compared with cell apoptosis before irradiation,x-radiation induced significantly high rat of cell apoptosis in the six cell lines at 12 h after 4 Gy X-radiation(t=5.27,P0.05).There was a negative correlation between the changes of radiation-induced apoptosis and cell cycle S phase and G2-M phase in SMMC-7721,HCI-H460 and A549.There were two peaks of radiation-induced apoptosis at 12 h and 36 h after the irradiation in HCI-H460.There was a G2-M cell cycle arrest at 12 h in HepG2 and at 24 h in HL-7702 and Hela.CONCLUSIONS:There might be a premitotic apoptosis after 4 Gy X-radiation in all the 6 cell lines above mentioned.There might be a postmitotic apoptosis in HCI-H460.