RNAi抑制存活素基因表达对前列腺癌细胞侵袭的影响

目的 探讨存活素(survivin)基因对前列腺癌细胞侵袭的影响和可能机制. 方法 采用survivin基因小干扰RNA(small interfering RNA,siRNA)转染处理人前列腺癌细胞系PC-3后,分别采用实时-定量RF PCR和Western blot检测survivin基因和基质金属蛋白酶家族-2、-9(matrixmetalloproteinases-2、-9)mRNA和蛋白水平,分别采用软琼脂集落培养试验和Boyden小室模型试验检测癌细胞的锚着不依赖性增殖和侵袭能力;其次,将转染48 h的细胞接种裸鼠,观察对癌细胞体内侵袭的影响. 结果 软琼脂集落形成试验显示,3.125、6.250 nmol/L和12.500 nmol/L siRNA组集落形成数分别为17.8±1.6、13.6±1.5、8.8±1.4,而对照组为22.65±1.8(P<0.05);Boyden小室模型试验显示,3.125、6.250 nmol/L和12.500/ nmol/L siRNA组穿过滤膜的细胞数分别为33.6±2.1、19.5±1.9、8.1±1.8,而对照组为49.4±2.3(P<0.05).体内试验显示,对照组裸鼠组织癌细胞侵袭横纹肌和血管,而转染组未见这些现象.同时发现,转染组细胞MMP-2、-9基因mRNA和蛋白水平明显下调,呈浓度和时间依赖性(P<0.01). 结论 采用survivin siRNA转染可抑制前列腺癌细胞侵袭转移,其机制可能与下调MMP-2和MMP-9表达有关.

Effects of RNA interference-mediated silencing expression of survivin gene on invasion of human prostate cancer cell

Objective To study the effects and mechanism of survivin gene on invasion of prostate cancer cell. Methods After PC-3 prostate cancer cell lines were transfected by survivin small interfering RNA (siRNA), the mRNA and protein of survivin and matrix metalloproteinase-2 and-9 were determined by real time RT-PCR and western blot assay, respectively. The anchorage-independent growth was examined by clon formation in soft agar, and invasion ability was evaluated by boyden chamber model. The invasion ability of cancer cells in vivo was determined by nude mice model. Results The results from clon formation in soft agar showed that the colonies numbers of group of 3.125,6.250 and 12.500 nmol/L of siRNA were 17.8±1.6,13.6±1.5 and 8.8±1.4, and the control group was 22.6±1.8(P<0.05). The results from boyden chamber model exhibited that the cells numbers crossing filter membrane in group of 3.125,6.25 and 12.5 nmol/L of siRNA were 33.6±2.1,19.5±1.9,8.1±1.83, and the control group was 49.4±2.3(all P<0.05). The results in vivo showed that cancer cells of control groups invaded into striped muscle and blood vessel, and there were no these phenomenons in transferred group with survivin siRNA. Survivin siRNA could reduce expression level of MMP-2 and MMP-9 in prostate cancer cells(P<0. 01). Conclusions Survivin-directed RNA interference can inhibit invasion of human prostate cancer cell through down-regualting MMP-2,-9 genes.