人肝癌细胞和肝细胞放射敏感性的体外研究

Radiosensitivity of human hepatocarcinoma cell line and hepatic cell line in vitro

目的观察人肝癌细胞株HepG2及人肝细胞株QSG-7701对高能X线照射的敏感性和时相差异。方法用吸收剂量为5Gy的6MVX线单次照射体外培养的HepG2细胞及QSG-7701细胞,以MTT比色法测定细胞在受照后不同时间的存活率,分别采用流式细胞术和激光共聚焦显微镜观测细胞凋亡率和形态变化。结果高能X线照射后6hHepG2细胞凋亡率达到高峰(32%),存活率最低(62%),而QSG-7701细胞在照射后24h凋亡率和存活率才分别达高峰(17%)和低谷(82%)。两株细胞单次照射后6h的凋亡率和存活率差异最大。结论高能X线能够诱导人肝癌细胞株HepG2及人肝细胞株QSG-7701发生凋亡,两株细胞存在不同的敏感性和时相差异,HepG2细胞对射线敏感性比QSG-7701细胞高,HepG2细胞凋亡高峰明显早于QSG-7701细胞。

Objective To study the differences between human hepatocarcinoma cell line HepG2 and hepatic cell line QSG-7701 in the radiosensitivity and time course to high-energy X-ray. Methods HepG2 cells and QSG-7701 cells were cultured in vitro and irradiated under 6MV X-ray with a single dose of 5 Gy. The survivability of HepG2 cells and QSG-7701 cells was measured by methyl thiazole tetrazolium （MTT） assay at different time points after irradiation. The apoptosis and morphological changes were detected by flow cytometry （FCM） and laser scanning confocal microscope （LSCM）,respectively. Results The apoptosis rate of HepG2 cells reached its peak（32%） with the lowest survivability of 62% at 6h after irradiation,while QSG-7701 cells got the highest apoptosis rate（17%）and lowest survivability （82%） at 24h after irradiation. There were significant differences between the two cell lines in apoptosis rate and survivability at 6h after irradiation. Conclusion Apoptosis was induced in both human hepatocarcinoma cell line HepG2 and hepatic cell line QSG-7701 by high-energy X-ray. In comparison with QSG-7701,HepG2 had a higher radiosensitivity and earlier apoptosis peak.