雷帕霉素对白血病细胞株的影响

本研究探讨雷帕霉素对白血病细胞株的增殖抑制作用及其对细胞周期的影响，并分析该药作用前后mTOR mRNA表达水平的变化。采用四唑氮蓝比色试验（MTT）观察雷帕霉素对白血病细胞株KG1、K562和U937的体外增殖抑制作用；应用流式细胞术（FCM）检测雷帕霉素干预后的白血病细胞株的细胞周期的阻滞情况；采用实时荧光定量PCR检测白血病细胞株的mTORmRNA表达。结果表明：不同浓度的雷帕霉素作用于KG1细胞株时，20nmol／L为最佳有效浓度，细胞被明显抑制，细胞周期阻滞在G0／G1期，细胞凋亡明显，mTORmRNA的表达水平亦显著降低。与雷帕霉素作用于KG1细胞株相比，雷帕霉素对K562和U937细胞株的作用相对较弱。结论：雷帕霉素与mTOR结合后可以抑制细胞增殖，KG1细胞株对雷帕霉素最为敏感。

Effect of Rapamycin on Leukemia Cell Lines

This study was aimed to investigate the effect of rapamycin on proliferation and cell cycle of leukemic cell lines and to analyze the changes of mTOR mRNA expression before and after treatment with rapamycin. The leukemic cell lines KG1, K562 and U937 were treated with rapamycin of different concentrations. The MTT assay was used to detect the effect of rapamycin on proliferation of leukemic cell lines before and after treatment with rapamycin, the real- time quantitative PCR was used to investigate the expression of mTOR mRNA. The results indicated that the optimal effective concentration of rapamycin for KG1 was 20 nmol/L, showing significant inhibitive effect on cell growth, arrest of cells in G0/Gj phase, obvious apptosis of cells and significant decrease of mTOR mRNA expression level. As compared with KGI cell lines, K562 and U937 did not show significant response to rapamycin. It is concluded that the rapamycin can inhibit cell proliferation. As compared with and the K562 and U937 cells, the KG1 cells are sensitive to rapamycin.