节拍器化疗对鼻咽癌CNE-1细胞周期和凋亡的影响

目的探讨顺铂节拍器化疗对人鼻咽癌细胞CNE-1细胞周期和细胞凋亡的影响。方法采用MTT方法,检测顺铂对鼻咽癌细胞株CNE-1的半抑制浓度（IC50）,相当于临床中采用6 mg/m^2顺铂小剂量连续化疗的血浆浓度。以低于此浓度的0.10μg/ml作为顺铂节拍器体外化疗参考剂量,采用流式细胞术检测0.10μg/ml顺铂连续作用12 h和96 h细胞周期和细胞凋亡的变化情况。结果MTT法检测顺铂半抑制浓度IC50为0.19μg/ml,0.10μg/ml顺铂作用12 h后检测细胞周期变化,与对照组比较无显著变化;而作用96 h后与对照组相比进入G2/M期细胞比例显著增多,两者差异有统计学意义（P〈0.05）,但作用12 h和96 h后均未检测到明显细胞凋亡现象。结论采用小剂量顺铂作用足够长时间,可以诱导鼻咽癌CNE-1细胞周期发生变化,但是并不能诱导细胞凋亡。细胞周期同步化于G2/M期,为节拍器化疗与放疗的联用提供了可能。

Effect of Metronomic Chemotherapy on Cell Cycle and Apoptosis in Human Nasopharyngeal Carcinoma CNE-1 Cells

Objective To investigate the effect of metronomic chemotherapy on cell cycle and apoptosis in human nasopharyngeal carcinoma CNE - 1 cells. Methods IC50of cisplatin to CNE - 1, corresponding to 6 mg/m^2 continuous treatment clinically, was evaluated by MTT assay. After continuous treatment by 0.10 g,/ml of eisplatin for 12 and 96 hours, Cell cycle distribution and apoptosis of CNE - 1 were measured by flow cytometer. Results The IC50 of cisplatin estimated by MTT assay was 0.19 Ixg/ml. The cell cycle distribution after treatment with 0.10 μg/ml of cisplatin for 12 hours was not changed significantly compared with the controls ; whereas treatment with cisplatin for 96 hours in the same dose induced significantly larger populations of cells in G2/M phase compared with the untreated cells. No evidence of apoptosis could be detected after treatment with cisplatin for 12 hours or 96 hours. Conclusion Low dose continuous treatment of cisplatin could induce the cell cycle re - distribution of CNE-1 cells to the G2/M phase. This might be the basis of the combined treatment of radiotherapy and metronomic chemotherapy.