高温阻滞HeLa细胞于G_1期并引起G_1期细胞凋亡

G _1 Arrest and Apoptosis Induced by Hyperthermia in HeLa Cells

目的 探讨高温阻滞 HeLa细胞周期进程及其与细胞凋亡的关系。方法 HeLa细胞经培养增殖后分为37 ℃、40 ℃、43 ℃和45 ℃共4个温度组。每组分别在0 .5、1、2和4 h共 4 个时间点取材, 经 PI染色在流式细胞仪上检测4种温度条件下, 4个时间段时HeLa细胞的凋亡指数和在各细胞周期时相中的指数。结果 37 ℃时, 60%的细胞处于G1期, S期及G2/M期的HeLa细胞分别为17%和18%, 约5%细胞凋亡。40 ℃时, 细胞周期受到抑制,G1期的HeLa细胞明显增加, 达73%, S及G2/M期的细胞分别为9%和15%, 凋亡细胞占3%。43 ℃时, 不但细胞周期受阻, 而且凋亡细胞极明显地增加, 达 19%, G1 期细胞为 61%, S期细胞为 9%, G2/M期细胞为 11%。45 ℃时, 细胞凋亡数和在细胞周期各时相的细胞数与40 ℃时的分布相似。结论 温度升至40 ℃时对HeLa细胞的增殖活动有明显的抑制, 使HeLa细胞滞留于G1期。43 ℃时除了细胞周期受抑制外, 凋亡细胞明显增加, 这可能是由于细胞周期受阻和高温启动了凋亡机制而诱发了细胞凋亡, 凋亡的细胞主要为 G1期的细胞。45 ℃以上的高温对 HeLa细胞的杀伤失去对周期时相的选择性, 均等地杀伤细胞周期各时相的细胞。

Objective To study the effect of hyperthermia on the cell cycle of HeLa cell and the relationship between the cell cycle and apoptosis.Methods The HeLa cells were divided into 4 groups,and placed at 37 ℃,40 ℃,43 ℃ and 45 ℃ respectively.Each group was heated for 0.5 h,1 h,2 h and 4 h.The apoptosis and the cells at the different phases were tested in cell cycle by the flow cytometry.Results At 37 ℃,60 % of HeLa cells were in G 1,17% in S,18% in G 2/M respectively and about 5 % of HeLa cells had apoptosis.At 40 ℃,the cell cycle was blocked,and 73 % of HeLa cells were in G 1,9% in S,15% in G 2/M and about 3 % of HeLa cells had apoptosis.At 43 ℃,the cell cycle was blocked and the apoptosis of the cells was increased simultaneously.19% of HeLa cells had apoptosis,and 61 % in G 1,9% in S and 11% in G 2/M.At 45 ℃,the distribution of HeLa cells in different phases and the apoptosis were similar to that at 40 ℃.Conclusion The hyperthermia,at 40 ℃ and 43 ℃,could remarkably block the proliferation of HeLa cells and the cells were arrested in G 1 phase.At 43 ℃,hyperthermia-induced apoptosis was remarkably increased.The hyperthermia,above 45 ℃,equally killed the cells in different phases.