ObjectiveTo explore the effect of small interference RNA (siRNA) on the metastasis and invasion of A549 cells after silence the E-cadherin gene (CDH1).MethodsThe CDH1 gene in A549 cells was silenced by siRNA technology, and RT-QPCR and Western blot were used to detect the gene expression and protein expression after silencing. The cells were divided into control group (Control), siRNA negative group (siRNA-NC) and siRNA gene silencing group (siRNA-CDH1). CCK-8 detected cell viability after the gene silencing in 12 h, 24 h, 48 h and 72 h, and cell scratch test to detect cell migration ability. Transwell chamber was used to detect cell invasiveness, and Western blot method was used to detect the expression level of key factors which involved in cell migration, invasion, such as vimentin, matrix metalloproteinases (MMP-2 and MMP-9), and N-cadherin. RT-QPCR was employed to detect the mRNA expression of vimentin, MMP-2, MMP-9, Slug and Snail.ResultsAfter CDH1 silencing, the activity of A549 cells increased significantly and was time-dependent, compared with Control group and siRNA-NC group (P<0.05). The cell scratch test and Transwell chamber test showed that the cell migration and invasion ability increased significantly after CDH1 silencing, compared with Control group and siRNA-NC group (P<0.05). The expression of vimentin, MMP-9, MMP-2 and N-cadherin in siRNA-CDH1 group increased significantly. The mRNA expression level of vimentin, MMP-9, MMP-2 and Slug and Snail also increased. Compared with Control group and siRNA-NC group, the difference was statistically significant (P<0.05).ConclusionCDH1 plays an important role in tumor proliferation and invasion, and its deletion can increase the proliferation and invasion ability of A549 cells.