丝裂霉素诱导CHO-K1细胞凋亡及对其细胞周期的影响

Reseach of Apoptosis Induced by Mytomycin in CHO-K1 Cell Line and Effect on Cell Cycle

采用荧光探针染色法,琼脂糖凝胶电泳分析方法,流式细胞仪技术研究丝裂霉素诱导CHO K1细胞凋亡及对其细胞周期的影响.结果显示,丝裂霉素处理CHO K1细胞后,细胞核质收缩凝集,核碎裂及出现凋亡小体;琼脂糖电泳呈现典型的DNA梯带;流式细胞仪检测到典型的细胞凋亡峰(亚G1峰),分别用10,15,20,25mg/L丝裂霉素处理CHO K1细胞,其细胞凋亡率分别为4.76%,9.20%,14.51%,37.46%,且凋亡率随药物浓度的升高而升高,显示两者的正相关性;作用浓度相同而改变处理时间时,发现细胞凋亡率随处理时间的延长而呈上升趋势;流式细胞仪细胞周期分析,显示随着丝裂霉素浓度提高或作用时间延长,G1 S期细胞百分比降低,G2/M期细胞百分比升高,Ap峰与G1 S期负相关,与G2/M期正相关.

Apoptosis induced by mytomycin in the CHO-K1 cells was identified with fluorescent probe staining、agarose gel electrophoresis and flow cytrometry. The results showed that the CHO-K1 cells exposed to mytomycin exhibited morphologically change of apoptosis:chromatin condensation ,nucleour disintegration,formation of apoptotic bodies were observed in these cells with Hoechst 33258 fluorescent probe staining. Flow cytometry analysis showed specific hypodiploid peak(sub-G_(1) peak). Cell cycle analysis showed that DNA content in S period declined where as it rose considerably in G_(2)/M period.Sub-G_(1) peak was negative correlated with S period and positive correlated with G_(2)/M period. Apoptotic bodies up to,4.76%,9.20%,14.51%,37.46% when the cells treated with 10,15,20,25 mg/L mytomycin respectively, which showed that the apoptosis induced by mytomycin was dose-dependent.The result from this paper also showed the percentage of apoptotic body rose apparently after treated the CHO-K1 cells with the same concentration of mytomycin at different time which proved the apoptosis was time-dependent.