Down Expression Of Astrocyte Elevated Gene-1is Effect On Cell Proliferation And Chemosensitivity In Lung Adenocarcinoma A549Cells

BackgroundIn recent years, the incidence and mortality of lung cancer showed a rising trend.Lung cancer has become one of the major public health problems that threaten humanhealth. Since the clinical manifestations are poor specificity in early lung cancer,resulting in the majority of lung cancer patients have been too late at diagnosis. Theyhave lost surgery opportunity, and accepted conservative treatment. There arechemotherapy, radiotherapy and combined therapy in clinical, but these treatments arestiii unable to save the lives of patients with lung cancer. Most lung cancerpatients’conditions will continue to deteriorate during treatment, and lung cancerresistanting to chemotherapy drugs. However, the study found that the mechanism oftumor cells to chemotherapeutic drug resistance is very complex, including targetgene mutation, DNA damage repair system enhancements, abnormal expression ofmembrane protein drug pump, the cell membrane enzyme abnormalities, abnormalcell apoptosis, autophagy and so on. Therefore, exploring and researching themechanism of lung cancer resistant to chemotherapy treatment, and it will be great significance for the treatment of lung cancer. At present, the studies of lung cancerresistance mechanisms, including some related genes, proteins, signal transductionpathways, which makes research in the field of molecular biology to biologicalchanges in the level of the cell level. In recent years, the study of gene expressionassociated with lung cancer has become one of the hot field of molecular biology.With further progress of the study, more targeted gene therapy will be available in thefuture. This is undoubtedly important clinical significance for lung cancer treatment,and it also provides a new idea for the study of anti-cancer drugs.Astrocyte elevated gene-1(AEG-1) is a newly discovered gene since2002. It hascomplex molecular structures, and involving in tumor cell proliferation, invasion,metastasis, protective autophagy and many other aspects. It has been reported thatAEG-1gene expression is high in non-small cell lung cancer, its expression is higher,the survival of lung cancer patients is shorter, and the gene can activate PI3K/Akt、NF-κB signaling pathway, promoting invasion and metastasis of non-small cell lungcancer. However, over expression of AEG-1can if influence the proliferation ofcancer cells, and involved in non-small cell lung cancer resistance, current literaturerarely reported. In view of this, the project is mainly to study AEG-1gene innon-small cell lung cancer proliferation and chemosensitivity, and lay the foundationfor the study of specific molecular mechanism.ObjectiveChemically synthesized AEG-1shRNA was transfected into lungadenocarcinoma A549cells, and the intracellular AEG-1downregulation. Thendetecting cell proliferation and whether the drug sensitivity of the transfected lungadenocarcinoma A549cells to cisplatin have changed by MTT.Methods1. Divided into three groups: blank control group, AEG-1shRNA group, controlshRNA group. Firstly, cultured lung adenocarcinoma A549cells. Secondly,chemically synthesized AEG-1shRNA was transfected into lung adenocarcinomaA549cells by the reage Lipofectamine2000. After24hours and48hours, detectingfluorescence expression under a fluorescence microscopy. After48hours, collecting the cells to extract protein and Western-Blot test，compared the expression of AEG-1protein.2. Divided into three groups: control group, transfected group and untransfectedgroup. Detecting cell proliferation and whether the drug sensitivity of the transfectedlung adenocarcinoma A549cells to cisplatin have changed by MTT.Result1.Chemically synthesized AEG-1shRNA was transfected into lungadenocarcinoma A549cells. Under fluorescence microscope, the transfectionefficiency was up to80%, AEG-1expression was significantly decreased aftertransfection(t=1.89,P＜0.05).2. Using MTT assay, AEG-1downregulation inhibits the proliferation of lungadenocarcinoma A549cells. A549cells proliferation inhibition rate is respective54.5%and59.8%after transfection48h,72h. Compared with the control group, the pvalue is less that0.05. Using the same dose and concentration of drug, the cellproliferation of the transfected cells is lower than non-transfected cells. When thedrug concentration is0.20μg/ml，0.25μg/ml, the p value is less than0.05,significant difference between transfected and untransfected. MTT assay the IC50ofthe transfected group to cisplatin is0.16μg/ml and the untransfected group is0.21μg/ml. Compared to the untransfected group, the IC50of the transfected group islower25.1%.Conclusions1. AEG-1shRNA plasmid is transfected into human lung adenocarcinoma A549cells, inhibition of intracellular AEG-1gene expression.2. Down expression of AEG-1can inhibit the cell proliferation and enhancedsensitivity to cisplatin in lung adenocarcinoma A549cells.