蝎毒多肽提取物诱导前列腺癌DU-145细胞凋亡的实验研究

Polypeptide Extract from Scorpion Venom(PESV)Induces Apoptosis of DU-145 Cells in Vitro

目的探讨蝎毒多肽提取物(PESV)诱导前列腺癌DU-145细胞凋亡的作用及机制。方法用PESV(40μg/mL)处理DU-145细胞,采用Gimesa染色法观察凋亡细胞形态变化;采用免疫组化S-P法检测核增殖抗原Ki-67及凋亡相关基因bax和bcl-2的表达,并用病理图像分析软件进行半定量分析;TUNEL法检测凋亡细胞,并计算前列腺癌细胞增殖指数(proliferating in-dex,PI)和凋亡指数(apoptosis index,AI)。结果PESV在体外对DU-145细胞有中度增殖抑制效应;在PESV作用下,DU-145细胞出现显著的细胞凋亡征象,凋亡指数明显增高,增殖指数降低,AI/PI明显增高(P<0.05)。PESV处理DU-145细胞可明显提高凋亡相关基因bax表达水平,降低凋亡抑制蛋白Bcl-2表达水平,使Bcl-2/Bax比值明显减小(P<0.05)。结论PESV(40μg/mL)可以诱导细胞凋亡,而且至少是通过促进Bax、抑制Bcl-2基因表达的机制诱导细胞凋亡。

Objective To investigate the underlying mechanism of apoptosis-inducing effect of Polypeptide extract from scorpion venom （PESV） in prostatic cancer cells. Methods Apoptotic cells were screened by Gimesa and TdT-mediated dUTP-biotin nick-end labeling （TUNEL） method. Immunohistochemistry was used to measure proliferating antigen, Ki67 and apoptosis-related proteins,Bax,Bcl-2. The proliferating index（PI）and the apoptotic index（AI） of DU145 was calculated. Results The morphology of DU-145 cells were characterized by apoptosis feature such as nuclear chromatin condensation ang fragmentation. Treatment of prostatic cancer cells with PESV caused a significant elevation of the pro-apoptotic protein Bax and higher apoptosis index（M）, induced apoptosis. Conclusion PESV induces apoptosis in prostatic cancer cells at least partly through the up-regulation of Bax, and downregulation of Bcl-2.