生存素在紫杉醇诱导肝癌细胞株SMMC-7721凋亡中的作用

Role of survivin in paclitaxel-induced apoptosis of hepatic carcinoma cell lines SMMC-7721

目的探讨凋亡抑制蛋白生存素在紫杉醇诱导肝癌细胞株SMMC-7721凋亡中的作用。方法用紫杉醇浓度为1、10、100、1000、10 000ng/ml(分别为A、B、C、D、E组)诱导肝癌细胞株SMMC-7721 24h后,采用MTT法检测细胞抑制率,台盼蓝染色观察细胞凋亡情况;另设空白对照(F)组。以紫杉醇0、0.375、3.75、37.5、375、3750ng/ml诱导肝癌细胞株SMMC-7721 24h,采用RT-PCR和Western blot检测生存素的mRNA和蛋白表达。结果 A、B、C、D、E组的细胞抑制率分别为10.2%、37.1%、65.5%、86.3%、92.7%。B、C、D、E组细胞凋亡率均高于F组[(18.2±3.0)%、(53.5±4.7)%、(73.6±3.4)%、(84.2±5.6)%vs.(3.3±1.6)%](P<0.05)。当诱导浓度≤3.75ng/ml时,生存素mRNA及蛋白水平随浓度增加而升高;而当诱导浓度≥37.5ng/ml时,生存素mRNA及蛋白水平随浓度增加而下降(P<0.05)。结论生存素表达的下调可能促进紫杉醇诱导肝癌细胞株SMMC-7721凋亡的作用。

Objective To explore the role of survivin in paclitaxel-induced apoptosis of hepatic carcinoma cell line SMMC-7721. Methods SMMC-7721 cells were assigned into six groups. Groups of A,B, C, D and E were treated with paclitaxel in the concentrations of 1, 10, 100, 1000 and 10 000 ng/ml,respectively,for 24 hours. Group F was taken as blank control. The cell inhibition rate was detected by MTT assay and apoptosis was observed by trypan blue staining. After SMMC-7721 was induced with paclitaxel in the concentrations of 0. 375,3.75,37.5,375,3750 ng/ml, respectively, for 24 hours, the expressions of survivin mRNA and protein were detected by RTPCR and Western blot, respectively. Results The apoptosis rate of groups of A, B, C, D and E was 10. 2%, 37.1%, 65.5% ,86.3% and 92.7 %, respectively. The apoptosis rate was higher in groups of B, C, D and E than that in group F [（18. 2±3.0）%, （53.5±4.7）%, （73.6±3.4）%, （84.2±5.6）% vs. （3.3± 1.6） %]（P〈0. 05）. The expressions of survivin mRNA and protein were increased with an increase of concentration when it was 43.75 ng/ml, which were decreased with an increase of concentration when it was ≥37. 5 ng/ml（P〈0. 05）. Conclusion Downregulation of survivin may promote paclitaxelinduced apoptosis of SMMC-7721.