siRNA 靶向沉默 Lipocalin-2基因下调 MMP-9表达对降低人肺癌 A549细胞的侵袭、迁移能力的影响

目的：利用针对 Lipocalin-2的小干扰 RNA（siRNA），观察 Lipocalin-2基因沉默对人肺癌 A549细胞MMP-9表达及侵袭、迁移能力的影响。方法采用 Real-time PCR 和 Western blot 检测 Lipocalin-2在3种肺癌细胞株（A549、NCI-H661、NCI-H446）及正常人支气管上皮细胞（HBE）的表达情况。设计并构建靶向 Lipocalin-2的 siRNA 转染 A549细胞，采用 Real-time PCR 和 Western blot 检测转染效率及 Lipocalin-2基因沉默对 MMP-9 mRNA 和蛋白表达的影响。Transwell 小室检测细胞侵袭能力。细胞划痕实验检测细胞迁移能力。结果 Lipocalin-2 mRNA 和蛋白在肺癌A549、NCI-H661、NCI-H446细胞株中的表达水平均显著高于 HBE 细胞，差异有统计学意义（ P ＜0.05）。siRNA-Li-pocalin-2转染组 Lipocalin-2 mRNA 和蛋白表达水平与阴性对照组和空载体对照组比较，差异有统计学意义（ P ＜0.05）；siRNA-Lipocalin-2转染组 MMP-9 mRNA 和蛋白表达水平与阴性对照组和空载体对照组比较，差异有统计学意义（ P ＜0.05）；siRNA-Lipocalin-2转染组穿膜细胞数、平均迁移距离与阴性对照组和空载体对照组比较，差异有统计学意义（ P ＜0.05）。结论 Lipocalin-2基因沉默通过下调 MMP-9表达降低了人肺癌 A549细胞的侵袭和迁移能力。

Effects of Lipocalin-2 gene silen cing on the expression of MMP-9 and the metastasis and invasion abilities of human lung cancer A549 cells in vitro

Objective To investigate the effects of gene silencing of Lipocalin-2 on the expression of MMP-9 and metastasis and invasion abilities of human lung cancer A549 cells in vitro. Methods The expression levels of Lipocalin-2 mRNA and protein in 3 kinds of human lung cancer cell lines(A549,NCI-H661,NCI-H446)and healthy human bronchial epithelial cells(HBE)were detected by Real-time PCR and Western Blot,respectively. The targeting Lipocalin-2 siRNA was established and transfected into A549 cells via lentivirus. Transfection efficiency and the expression levels of MMP-9 mRNA and protein were detected by Real-time PCR and Western Blot. Moreover the invasive ability and migration ability of A549 cells were detected by Transwell assay and scratch test,respectively. Results The expression levels of Lipocalin-2 mRNA and protein in A549,NCI-H661,NCI-H446 cells were significantly higher than those in HBE cells( P < 0. 05),furthermore, there were significant differences in the expression levels of Lipocalin-2 mRNA and protein between siRNA-Lipocalin-2 transfection group and negative control group as well as empty vector control group( P < 0. 05). Besides there were significant differences in the cell number with membrane tresis and average migration distance between siRNA-Lipocalin-2 transfection group and negative control group as well as empty vector control group( P < 0. 05). Conclusion Lipocalin-2 gene silencing can decrease metastasis and invasion abilities of human lung cancer A549 cells in vitro through down-regulating the expression levels of MMP-9.