高温对HeLa细胞周期及周期因子Cyclin E和Cyclin A的影响

Effects of hyperthermia on the cell cycle and Cyclins E and A of HeLa cells

目的 探讨高温时HeLa细胞周期进程受阻与细胞周期因子CyclinE和CyclinA表达的关系。方法 将人子宫颈癌细胞株 (HeLa细胞 )分为 3 7℃、40℃和 43℃ 3个温度组 ,每组均以相应的温度作用 1h。采用流式细胞仪检测各组HeLa细胞的细胞周期、免疫细胞化学方法测定其CyclinE和CyclinA的表达 ,并以图像分析仪测定免疫组织化学反应物的光密度 (OD)。结果 40℃和 43℃时 ,细胞周期受阻 ,大量细胞滞留于G1期 ,S期和G2 /M期的细胞明显减少。CyclinE和CyclinA免疫反应阳性细胞明显减少、反应强度明显减弱。随着温度的升高 ,CyclinE和CyclinA免疫反应产物的平均OD值逐渐减小。结论 高温抑制了CyclinE和Cy clinA的活性 ,阻滞了细胞周期的进程 ,使HeLa细胞滞留于G1期。

Objective To investigate the relationship between the expression of Cyclins E and A and the cell cycle block caused by hyperthermia of HeLa cells. Methods The HeLa cells were divided into three groups and treated with temperatures of 37℃,40℃ and 43℃, respectively, for 1h. Then the cell cycle phases were measured by use of the flow cytometry, and the expression of Cyclins E and A were assessed by use of immunocytochemistry methods. The optical densities (OD) of immunohistochemical reactants were appraised by use of image analyzer. Results The cell cycle of HeLa cells was blocked at 40℃ and 43℃, and a large number of cells were arrested in G 1 phase while the cells in S and G 2/M phases were decreased markedly. The positive cells of immunoreaction of Cyclins E and A were decreased significantly and the immunoactivities of Cyclins E and A were weakened significantly. The average ODs of immunoreaction of Cyclins E and A were reduced gradually from 37℃ to 43℃. Conclusion The activities of Cyclins E and A were inhibited by hyperthermia, and the cell cycle of HeLa cells was blocked and arrested in G 1 phase.