PLK1基因沉默增强K562/A02细胞对阿霉素敏感性的实验研究

Enhancive Effect of PLK1 Gene Silencing on Sensitivity of K562/A02 Cells to Adriamycin

背景与目的:Polo样激酶1(polo-likekinase1,PLK1)是一种重要的细胞周期调节分子,在多种肿瘤细胞中高表达且与肿瘤发病、治疗和预后密切相关。本研究探讨PLK1基因沉默增强K562/A02细胞对阿霉素敏感性的作用。方法:构建针对PLK1mRNA的siRNA真核质粒,将其导入经阿霉素诱导的K562/A02细胞中,通过RT-PCR和Westernblot分析PLK1基因在转染前后的表达差异;MTT法检测阿霉素对K562/A02细胞的半数抑制浓度;流式细胞术检测细胞内阿霉素积累量和阿霉素诱导后的细胞凋亡。结果:与对照组相比,转染pEGFP-PLK1质粒的K562/A02细胞PLK1mRNA和蛋白水平分别下降(61.9±2.5)%和(65.3±2.4)%,对阿霉素敏感性的相对逆转率为67.8%。经阿霉素诱导96h后,空白对照组的细胞凋亡率为11.33%,转染pEGFP-PLK1质粒组凋亡率达到54.39%。结论:PLK1基因沉默能明显增加K562/A02细胞内阿霉素的累积量,增强细胞对阿霉素的敏感性并诱导凋亡,从而逆转K562/A02细胞对阿霉素的耐药性。

BACKGROUND ＆ OBJECTIVE： Polo-like kinase 1 （PLK1）, an important cell cycle regulator, is highly expressed in many types of cancer, and is associated with oncogenesis, treatment effectiveness and prognosis. This study was to investigate the enhancive effect of small interference RNA （siRNA） targeting PLK1 gene on the sensitivity of K562/A02 cells to adriamycin （ADM）. METHODS： siRNA plasmid vector specifically targeting PLK1 gene with enhanced green fluorescent protein （EGFP） was constructed and transfected into K562/A02 cells. The expression of PLK1 was detected by reverse transcription-polymerase chain reaction （RT-PCR） and Western blot. The 50% inhibitory concentration （IC50） of ADM on K562/A02 cells was measured by MTT assay. Intracellular ADM accumulation and ADM-induced apoptosis of K562/A02 cells were detected by flow cytometry. RESULTS： After treatment with PLK1 siRNA, the mRNA and protein levels of PLK1 in K562/A02 cells were decreased by （61.9±2.5）% and （65.3±2.4）% of control. The relative reverse rate of sensitivity of K562/A02 cells to ADM was 67.8%. The intracellular accumulation of ADM was greatly increased, and ADM-induced apoptosis of K562/A02 cells was elevated from 11.33% to 54.39%. CONCLUSION： PLK1 gene silencing could enhance intracellular ADM accumulation in K562/A02 cells, improve sensitivity of K562/A02 cells to ADM, and induce cell apoptosis, therefore, reverse cell resistant to ADM.