The Research Of Apelin-13on Lung Adenocarcinoma A549Cell Proliferation,Autophagy And Apoptosis

Aim：APJ is an orphan G protein-coupled receptor and its endogenous ligand is apelin. Thepurpose of this work is to study the relationship between apelin/APJ system and cellproliferation, cell autophagy and cell apoptosis of lung adenocarcinoma cell line A549cells.And to study the possible signal pathway which is relative to ERK1/2.Methods:1. The effect of apelin-13on the proliferation of human lung adenocarcinoma cellline A549was detected by CCK-8assay.2. Flow cytometry detected the distribution of the cell cycle and apoptosis rate.3. Apoptosis of human lung adenocarcinoma cell line A549was observed byhoechst33258;4. The expression of pERK1/2, ERK1/2, CyclinD1, LC3A/B, beclin1andCaspase-3in human lung adenocarcinoma cell line A549by western blot.5. Scan cell morphology and ultra-structure by AFM.Results:1.Apelin-13promotes lung adenocarcinoma cancer cell lines A549proliferation inconcentration and time dependent manner. Pre-incubation with ERK inhibitorPD98059(10μM) can significantly inhibit A549cell line proliferation induced byapelin-13. When pre-incubated by autophagy inhibitor3-MA or inducerrapamycin,cell proliferation has no significant difference on the effect ofapelin-13-induced proliferation. But while stimulated by3-MA or rapamycin aloneand respectively,both it can cause A549cell line proliferation; 2.Apelin-13can promote the transformation of G1/S phase and induce theapoptosis of A549.Apelin-13increases the rate of apoptosis,and ERK1/2inhibitorPD98059do not inhibit the apoptosis induced by apelin-13;3. Hoechst33258showed that Apelin-13can induce the apoptosis of A549cells;4.The western blot show that:Compared with control group,apelin-13cansignificantly increase the expression of pERK1/2,CyclinD1,LC3A/B,Beclin1andCaspase-3;Pre-incubation with ERK inhibitor PD98059inhibits the phosphorylationof ERK1/2and the expression of CyclinD1, LC3A/B and Beclin1induced byapelin-13,but has no obvious inhibition to the expression of Caspase-3;5.AFM showed the surface of human lung adenocarcinoma cell line A549havehole sturcture and apelin-13can cause the holes decrease and cell surface smooth andform glossy.Conclusion:1.ERK1/2mediates apelin-13-induced human lung adenocarcinoma cell lineA549proliferation and autophagy.2.Caspase-3plays an role in the apoptosis of apelin-13-induced human lungadenocarcinoma cell line A549.