miR-145通过靶向AP4对非小细胞肺癌A549细胞迁移侵袭的影响

目的探讨miR-145对非小细胞肺癌迁移与侵袭能力的影响及其可能的作用机制。方法 qRTPCR法检测非小细胞肺癌组织中miR-145和激活增强子结合蛋白4(activatingenhancerbindingprotein4, AP4)mRNA的表达。A549细胞转染miR-145mimic或者AP4siRNA后,划痕实验与Transwell小室法分别检测A549细胞的迁移与侵袭能力,qRT-PCR法与免疫印迹法(Western blot)检测A549细胞中AP4mRNA与蛋白表达水平;双荧光素酶报告基因法检测AP4mRNA与miR-145的关系。结果与癌旁正常组织相比,非小细胞肺癌组织中miR-145表达明显降低(P<0.05),而AP4 mRNA和蛋白表达均明显升高(均P<0.05);与对照组相比,转染miR-145 mimic后,A549细胞中miR-145表达明显升高(P<0.05),AP4 mRNA和蛋白水平明显降低(P<0.05);A549细胞的迁移数与侵袭能力均显著下降(均P<0.05);双荧光素酶报告基因法验证AP4 mRNA是miR-145的靶基因。A549细胞转染AP4siRNA后,A549细胞的迁移数与侵袭数显著下降(均P<0.05)。结论上调miR-145能抑制A549细胞的迁移与侵袭能力,可能与其抑制靶基因AP4表达有关。

miR-145 Attenuates Migration and Invasion of Non-small Cell Lung Cancer A549 Cells by Targeting AP4

Objective To investigate the effect of miR-145 on the migration and invasion of non-small cell lung cancer (NSCLC) cells and possible mechanism. Methods The expression of miR-145 and activating enhancer binding protein 4 (AP4) mRNA in NSCLC tissues were detected by qRT-PCR. After the transfection with miR-145 mimic or AP4 siRNA, the migration and invasion of A549 cells were examined by wound healing and Transwell assay, respectively; The mRNA and protein expressions of AP4 were detected by qRT-PCR and Western blot, respectively. The relationship between AP4 mRNA and miR-145 was detected by double luciferase reporter gene method. Results Compared with adjacent normal tissues, the level of miR-145 was significantly decreased in NSCLC tissues (P<0.05), however, the mRNA and protein levels of AP4 were significantly increased (P<0.05). Compared with control group, the level of miR-145 was significantly increased (P<0.05), the mRNA and protein levels of AP4 were significantly decreased (P<0.05), and cells migration and invasion were significantly decreased (P<0.05) in A549 cells after the transfection with miR-145 mimic. Moreover, AP4 was a direct target of miR-145. After the transfection with AP4 siRNA, the migration and invasion of A549 cells were significantly decreased (P<0.05). Conclusion miR-145 upregulation could efficiently attenuate the migration and invasion of A549 cells via inhibiting target gene AP4 expression.