RNA干扰沉默促肝细胞再生磷酸酶-3基因对结直肠癌细胞基质金属蛋白酶2和9表达的影响

Effects of phosphatase of regenerating liver cell-3 gene silence by RNA interference on the expression of matrix metalloproteinases-2,-9 in human colon cancer cells

目的探讨促肝细胞再生磷酸酶-3（PRL-3）基因对结直肠癌细胞侵袭的影响和可能机制。方法应用PRL-3基因小干扰RNA（siRNA）转染处理结直肠癌细胞系HCT116后，分别采用实时定量PCR和Western印迹检测PRL-3基因和基质金属蛋白酶家族（MMP）-2、MMP-9的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48h的细胞接种裸鼠，观察其在体内生长情况。结果体外实验结果显示，PRL-3siRNA可有效抑制结直肠癌细胞集落生长和侵袭能力，且与浓度相关（P〈0．05，P〈0．01））；转染组细胞MMP-2、MMP-9mRNA和蛋白水平明显下调（P〈0．05）。体内实验结果显示，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。结论采用PRL-3siRNA转染可抑制结直肠癌细胞侵袭，其机制可能与下调MMP表达有关。

Objective To explore the effects and associated mechanism of phosphatase of regenerating liver cell-3 （PRL-3） on the invasion of human colon cancer cell. Methods After colon cancer cell line HCT116 was transfected with PRL-3 small interfering RNA （siRNA）, the mRNA and protein expression of PRL-3 and matrix metalloproteinase ：2 （MMP-2） and MMP-9 were determined by real time RT-PCR and Western blot respectively. The anchorage-independent growth was examined using clone formation assay in soft agar, and invasion ability was evaluated by boyden chamber model. Then the transfcted HCT116 cells were implanted into nude mice and the tumor growth was observed. Results PRL-3 siRNA could inhibit anchorage-independent growth of HCTI16 cells in a dosedependent manner in vitro. The mRNA and protein expression of MMP-2 and MMP-9 were down-regulated by PRL-3 siRNA. HCTll6 cells invaded striated muscle and vessels in control nude mice but such phenomena were not found in transfected HCT116-implanted nude mice in vivo. Conclusion PRL-3 siRNA inhibit the invasion of colon cancer cells possibly through the down-regulation of MMP-2 and MMP-9.