三氧化二砷诱导人肝癌细胞凋亡及相关分子机制研究

Study on arsenic trioxide induced apoptosis in hepatoma cells andits molecular mechanism

目的 :研究三氧化二砷 (As2 O3 )诱导人肝癌细胞凋亡时 ,细胞周期及细胞周期调节蛋白的变化 ,探讨As2 O3 抗肝癌作用的分子机制。方法 :体外培养人肝癌细胞株SMMC - 772 1,用 2 μmol/LAs2 O3 处理 72h ,流式细胞仪检测细胞周期变化及细胞凋亡率 ;透射电镜观察细胞形态变化及细胞凋亡情况 ;免疫细胞化学检测cyclinD1、cyclinA、p2 1蛋白的表达。 结果 :As2 O3使SMMC - 772 1细胞周期阻滞在G0 /G1、S期 ,与对照组比较 ,As2 O3 在诱导SMMC - 772 1细胞发生凋亡的同时 ,p2 1蛋白的表达水平显著增高 (对照组 1.12 8;As2 O3 组 :3.794 ) ,cyclinD1、cyclinA蛋白的表达水平明显下降 (对照组 :3.6 4 7,2 .833;As2 O3组 :1.133,1.179)。结论 :As2 O3 能干扰细胞周期的进程 ,诱导SMMC - 772 1细胞凋亡。其作用机制与上调p2 1蛋白及下调cyclinD1。

Objective:To study the changes of cell cycle phase and cell cycle phase regulation protein during arsenic trioxide induced apoptosis in hepatoma cells,and to explore mechanisms of arsenic trioxide inhibited HCC.Methods:Cultured in vitre,HCC SMMC-7721 were treated 72h with 2μmol/L arsenic trioxide.The cell cycle and apoptosis index were detected by flow cytometry(FCM);the morphological changes were observed by transmission electron microscope.The immunohistochemistry was used to detect the protein expression of p21、cyclin D_1,cyclinA.Results:SMMC-7721 cell cycle was arrested in G_1 and S phase by arsenic trioxide.Compared with control in the course of apoptosis induced by arsenic trioxide p21 protein expressions rose significantly(control:1.128;arsenic trioxide:3.794),while cyclinD_1,cyclinA protein expressions decreased significantly(control 1:3.647,2.833;arsenic trioxide:1.133,1.179).Conclusion:Arsenic trioxide could disturb cell cycle progression of SMMC-7721 and induce apoptosis.The mechanism may relate to that arsenic trioxide up-regulate expression of p21 and down-regulate expression of cyclinD_1,cyclinA.