Abstract:

Objective To discuss the effect of interleukin-17 receptor B （IL-17RB） gene silencing on the proliferation， apoptosis and invasion of lung adenocarcinoma A549 cells， and to clarify its role in the occurrence and development of lung adenocarcinoma. Methods The normal human bronchial epithelial BEAS-2B cells and human lung adenocarcinoma A549 cells were cultured； real-time fluorescence quantitative PCR（RT-qPCR） and Western blotting method were used to detect the expression levels of IL-17RB mRNA and protein in the two kinds of cells. Liposome method was used to transfect IL-17RB small interfering RNA （si-RNA） fragments into the A549 cells， and the cells were divided into si-NC group and si-IL-17RB group. RT-qPCR and Western blotting methods were used to detect the silencing effect of IL-17RB； CCK-8 method was used to detect the proliferation activities of A549 cells in two groups； 5-ethynyl-2'-deoxyuridine （EdU） staining was used to detect the EdU positive cell rates of A549 cells in two groups； flow cytometry was used to detect the apoptotic rates of A549 cells in two groups； Transwell chamber assay was used to detect the numbers of migration cells and invasion cells of A549 cells in two groups； Western blotting method was used to detect the expression levels of B-cell lymphoma 2 （Bcl-2）， Bcl-2-associated X protein （Bax）， matrix metalloproteinase 9 （MMP-9）， N-cadherin， Vimentin， E-cadherin， Snail homolog （Snail） and phosphorylated P65 （p-P65） proteins in A549 cells in two groups. Results The RT-PCR results showed that compared with BEAS-2B cells， the expression levels of IL-17RB mRNA and protein in A549 cells were significantly increased （P<0.01）； compared with si-NC group， the expression levels of IL-17RB mRNA and protein in A549 cells in si-IL-17RB group were significantly decreased （P<0.01）. The CCK-8 assay results showed that compared with si-NC group， the proliferation activity of A549 cells in si-IL-17RB group was significantly decreased （P<0.01）. The EdU staining results showed that compared with si-NC group， the EdU positive cell rate of A549 cells in si-IL-17RB group was significantly decreased （P<0.01）. The flow cytometry results showed that compared with si-NC group， the apoptotic rate of A549 cells in si-IL-17RB group was significantly increased （P<0.01）. The Transwell chamber assay results showed that compared with si-NC group， the numbers of migration cells and invasion cells of A549 cells in si-IL-17RB group were significantly decreased （P<0.01）. The Western blotting results showed that compared with si-NC group， the expression levels of Bcl-2， Vimentin， N-cadherin， MMP-9， Snail and p-P65 proteins in A549 cells in si-IL-17RB group were significantly decreased （P<0.01）， while the expression levels of Bax and E-cadherin proteins were significantly increased （P<0.01）. Conclusion Silencing IL-17RB gene can reduce the proliferation and invasion abilities of lung adenocarcinoma A549 cells， promote cell apoptosis， and inhibit the expression level of p-P65 protein in cells； its mechanism may be related kinhibiting the nuclear factor-kappa B （NF-κB） singal pathway.

Key words: Interleukin-17 receptor B, Lung adenocarcinoma, Cell proliferation, Cell apoptosis, Epithelial-mesenchymal transition