Survivin shRNA增强人卵巢癌耐药细胞OVCAR3对泰素敏感性的研究

Effect of Survivin shRNA on Chemosensitivity of Human Ovarian Cancer Cell Line OVCAR3 to Paclitaxel

背景与目的:耐药是目前恶性肿瘤治疗急需解决的难题。最近研究显示,卵巢癌组织及细胞中均有Survivin高表达,可能与其抑癌耐药有关。本研究探讨Survivin的短发夹状RNA(shorthairpinRNA,shRNA)对人卵巢癌耐药细胞OVCAR3Survivin基因表达、凋亡及其对泰素、顺铂敏感性的影响。方法:脂质体介导SurvivinshRNA转染OVCAR3。转染空载体或脂质体的细胞及未转染细胞作为对照。逆转录聚合酶链反应(reversetranscription-polymerasechainreaction,RT-PCR)检测SurvivinmRNA的表达,流式细胞仪分析Survivin蛋白的表达及细胞凋亡率。四甲基偶氮唑蓝法(MTT法)测定SurvivinshRNA转染后OVCAR3细胞对泰素的敏感性。结果:与未转染组、空脂质体组、空载体组相比较,SurvivinshRNA处理24h后细胞SurvivinmRNA及蛋白表达水平均明显下调。SurvivinshRNA转染12、24、36、48h后的细胞凋亡率分别为20.7%、31.9%、39.0%、46.7%,呈时间依赖性。MTT结果显示,泰素对未转染组、空脂质体组、空载体组、转染组OVCAR3细胞的IC50分别为(0.305±0.032)μmol/L、(0.157±0.031)μmol/L、(0.175±0.010)μmol/L、(0.019±0.001)μmol/L;顺铂对4组OVCAR3细胞的IC50依次为(9.410±0.796)μmol/L、(6.675±1.739)μmol/L、(6.930±1.273)μmol/L、(7.862±0.081)μmol/L,SurvivinshRNA使OVCAR3对泰素的敏感性提高16倍(P<0.01),但是对顺铂的影响不大(P>0.05)。结论:靶向Survivin的序列特异性shRNA可有效抑制OVCAR3细胞中Survivin基因的表达,同时可以增强OVCAR3对泰素的敏感性,但不增加其对顺铂的敏感性。

BACKGROUND ＆ OBJECTIVE： Drug resistance is a major obstacle to the successful chemotherapy of ovarian cancer. Recent studies have shown overexpression of Survivin in ovarian cancer tissues and cell lines, which may play an important role in the drug resistance of ovarian cancer. This study was to explore the effects of Survivin short hairpin RNA （shRNA） on Survivin expression, apoptosis, and chemosensitivity of human ovarian cancer cell line OVCAR3. METHODS： OVCAR3 cells were transfected with Survivin shRNA. Untransfected, lip-transfected, and mU6-transfected cells were set as controls. Reverse transcription-polymerase chain reaction （RT-PCR） was used to detect the expression of Survivin mRNA. Flow cytometry was applied to examine the expression of Survivin protein and cell apoptosis. MTT assay was used to examine the effect of Survivin shRNA on chemosensitivity of OVCAR3 cells. RESULTS, The mRNA and protein levels of Survivin were obviously lower in Survivin shRNA-transfected OVCAR3 cells than in untransfected cells, lip-transfected cells, and mU6-transfected cells 24 h after transfection. The apoptotic rates of OVCAR3 ceiis 12 h, 24 h, 36 h, 48 h after Survivin shRNA transfection were 20.7%, 31.9%, 39.0%, and 46.7%, respectively, that showed a time-dependent manner. The 50% inhibitory concentrations （IC50） of paclitaxel were （0.305±0.032）μmol/L for untransfected cells, （0.157±0.031） μmol/L for lip-transfected cells, （0.175±0.010）μmol/L for mU6-transfected cells, and （0.019±0.001）μmol/L for Survivin shRNA-transfected cells; and the IC50 of cisplatin were （9.410±0.796） μmol/L, （6.675±1.739）μmol/L, （6.930±1.273）μmol/L, and （7.862± 0.081）μmol/L, respectively. Survivin shRNA increased the sensitivity of OVCAR3 cells to paclitaxel by 16 folds （P〈0.01）, but had no significant effect on the sensitivity to cisplatin （P〉0.05）. CONCLUSION, Sequence- specific shRNA targeting Survivin can suppress the expression of Survivin gene effectively in OVCAR3 cells, and sensitize OVCAR3 cells to paclitaxel, but has no significant effect on the sensitivity to cisplatin.