Abstract:

Abstract:Objective To investigate the  effect of C-erbB-2 shRNA on chemosensitivity of mouse lung adenocarcinoma cells and its mechanism,and to find new therapy method for non-small cell lung cancer,especial lung adenocarcinoma.Methods The mouse lung adenocarcinoma Lewis cells were cultured regularly and divided into non-transfected group,pGPU6/RFP/Neo-shNC group and pGPU6/RFP/Neo-erbB-2 group.The plasmids were synthesized and transfected into Lewis cells in each group by Lipofectamine 2000.The expression levels of C-erbB-2 mRNA and protein in the cel ls in various groups were tested by RT-PCR and Western blotting method,respectively.The Lewis cells were divided into non- transfected group,pGPU6/RFP/Neo-shNC group,carboplatin group,pGPU6/RFP/Neo-erbB-2 group,pGPU6/RFP/Neo-shNC+carboplatin group and pGPU6/RFP/Neo-erbB-2+carboplatin group.The apoptotic rates of the cells in each group were detected by flow cytometry;the expression levels  of Bcl-2 and Bax proteins in each group were determined by Western blotting method.Results The expression levels of C-erbB-2 mRNA and protein in pGPU6/RFP/Neo-erbB-2 group were lower than those in non- transfected group and pGPU6/RFP/Neo-shNC.The apoptotic rate of the cells in pGPU6/RFP/Neo-erbB-2+carboplatin group was the highest in all of the groups (P<0.01);compared with the others,the expression of Bax protein in pGPU6/RFP/Neo-erbB-2+carboplatin group was increased,while the expression level  of Bcl-2 protein was decreased.Conclusion C-erbB-2 shRNA can increase the Lewis cells’ sensitivity to carboplatin.The mechanism may be that it can enhance the Lewis cells’ apoptosis induced by carboplatin through increasing the expression of Bax protein and decreasing the expression of Bcl-2 protein.

Key words: CerbB-2, shRNA, lung adenocarcinoma cells, chemotherapy