华蟾素对人脑胶质瘤细胞SHG44增殖及凋亡的影响

Influence of cinobufotalin on the proliferation and apoptosis of human glioma cell line SHG44

目的初步探讨华蟾素对人脑胶质瘤细胞SHG44增殖、细胞周期分布及凋亡的影响机制。方法利用MTT法、流式细胞仪检测华蟾素对人脑胶质瘤细胞SHG44增殖及细胞周期变化的影响。AO/EB染色、透射电镜观察人脑胶质瘤细胞SHG44凋亡细胞形态学的变化。Western blot检测Bcl-2与Caspase 8蛋白的表达。结果华蟾素(1μg/ml、10μg/ml)对细胞株增殖具有显著抑制作用(P<0.05),并呈时间和浓度依赖性。流式细胞仪检测可见凋亡峰,G0/G1期细胞明显增多(P<0.05);华蟾素作用后可使Bcl-2蛋白表达降低,Caspase 8蛋白表达升高。结论华蟾素可调控人脑胶质瘤细胞SHG44的周期进程,诱导Bcl-2及Caspase 8差异性表达,且具有抑制肿瘤细胞增殖及促凋亡的作用。

Objective To explore the mechanism for cinobufotalin influencing proliferation, cell cycle and apoptosis of human glioma cell SHG44. Methods Human glioma cell SHG44 was cultured in vitro. The growth inhibitory effect of cinobufotalin on SHG44 cells was detected by MTT chromatometry. Cell cycle analysis was evaluated by flow cytometry. The morphological change and apoptosis alteration of SHG44 cells were identified by AO/EB staining and the ultrastructure of the cells was investigated by transmission electron microscopy. The expressions of Bcl-2 and caspase 8 in SHG44 cells were examined by Western blotting. Results Cinobufotalin （1 p^g/ml and I0 Ixg/ml） significantly inhibited the proliferation of SHG44 cells in a time- and concentration-dependent manner （P 〈 0.05）. Flow cytometry showed an apoptosis peak, the percentage of Go/G,-phase cells was significantly increased （P 〈 0.05）. The expression of Bcl-2 was decreased while that of caspase 8 protein was increased following cinobufotalin treatment. Conclusion Cinobufotalin can not only regulate cell cycles of human glioma cells cultured in vitro, but also induce differential expression of Bcl-2 and caspase 8, and possesses the role in inhibiting proliferation of rumor cells and accelerating apoptosis of SHG44 cells.