草苁蓉多糖提取物诱导人喉癌Hep2细胞凋亡的实验研究

Polysaccharide of boschniakia rossica induces apoptosis on Hep2 cells

目的：探讨草苁蓉多糖提取物（BRP）对人喉癌 Hep2细胞的抗瘤作用。方法：采用高通量色谱仪分析多糖提取物成分，流式细胞仪分析细胞周期及凋亡蛋白，western blot 检测细胞凋亡相关蛋白变化。结果：高通量色谱分析仪发现BRP成分单一，BRP对细胞的抑制率呈时间和浓度依赖性。细胞周期分析发现BRP使细胞滞留于G0/G1期。与对照组相比，不同浓度的BRP（100～400μg/ml）明显诱导细胞的凋亡。 Western blot 结果发现 BRP 作用后，pro-caspase-3，pro-caspase-8和pro-caspase-9蛋白分裂增加，同时死亡受体DR5和Bax表达增加，而Bcl-2表达减少。结论：研究发现BRP主要通过使 Hep2细胞周期变化和凋亡来抑制细胞的生长，其途径主要包括线粒体内部途径和死亡受体外部途径来完成。

Objective ：The aim of this study was to explore the anti-tumor potential of a polysaccharide isolated from Boschniakia rossica （BRP） in Hep2 human larynx squamous carcinoma cells .Methods ：By analyzing the extract polysaccharides of high-throughput chromatography ,cell cycle and apoptosis were analyzed by flow cytometry to changes in protein ,apoptosis was detected by Western blot related protein .Results ：High performance size-exclusion chromatography analysis showed that BRP was a homogeneous polysaccharide .BRP suppressed the proliferation of Hep2 cells in a time-and dose-dependent manner .Cell cycle analysis revealed that exposure to BRP （200μg/ml） caused a G0/G1 cell cycle arrest in Hep2 cells .Moreover ,treatment with BRP at 100-400μg/ml for 24 h induced a significant apoptosis Hep2 cells compared to untreated control cells ,as determined by flow cytometry with annexin-V/propidiumi odide double staining . Additionally , BRP treatment promoted the cleavage of procaspase-3 ,pro-caspase-8 ,and pro-caspase-9 ,coupled with increased expression of death receptor DR 5 and Bax and reduced expression of Bcl-2 .Conclusions：Taken together ,our data demonstrate that BRP shows potent anti-tumor activity in human larynx squamous carcinoma ,largely through induction of G0/G1 cell cycle arrest and apoptosis . Activation of both mitochondria-mediated and death receptor-mediated apoptosis pathways is involved in the cytotox-icity of BRP .