Research On The Regulation Of YAP To Lung Adenocarcinoma Stem Cells' Cisplatin Resisitance

Objective:1?To study and compare the expression of YAP m RNA and protein in A549 cells and A549 cell spheres.2?To study the influence of YAP on resistance to cisplatin of A549 cell spheres.Methods:1?Serum-free medium(SFM)was used to induce the formation of A549 cell spheres from A549 cells.2?With si RNA-YAP transfected into A549 cells and A549 cell spheres to reduce the m RNA and protein expressions of YAP.3?RT-PCR was use to measure the m RNA expressions of YAP in A549 cells and A549 cell spheres before and after transfection with si RNA.4?The protein levels of YAP1 of A549 cells and A549 cell spheres before and after transfection with si RNA were measured by Western Blot.5?Cells are treated with cisplatin for 24 h in 48 h after transfection with si RNA?6?CCK-8 was used to assesed the proliferation inhibition of A549 cells and A549 cell spheres.7? The apoptosis of A549 cells and A549 cell spheres was detected by flow cytometry.Results:1?(1) The m RNA and protein levels of YAP of A549 cells were lower than the A549 cell spheres(P<0.05).(2) Compared with the normal group, the m RNA and protein levels of YAP of A549 cells and A549 cell spheres were reduced after transfection with si RNA YAP(P<0.05).(3)The m RNA and protein levels of YAP between A549 cell and A549 cell spheres after transfection with si RNA YAP have no diffrerance(P>0.05).2?(1)The proliferation inhibition rate of A549 cells were higher than A549 cell spheres under the same si RNA transfection or cisplatin treatment(P<0.05).(2)The proliferation inhibition rate of both A549 cells and A549 cell spheres increased after downregulating the expression of YAP(P<0.05).(3)The proliferation inhibition rate induced by cisplatin both in A549 cells and A549 cell spheres increased significantly transfected with si RNA YAP compared with the corresponding cells transfected with si RNA NC(P<0.05).3?(1)The apoptosis rate of A549 cells were higher than A549 cell spheres under the same si RNA transfection or cisplatin treatment(P<0.05).(2)The apoptosis rate of both A549 cells and A549 cell spheres increased significantly after downregulating the expression of YAP(P<0.05).(3)The apoptosis rate induced by cisplatin both in A549 cells and A549 cell spheres increased significantly transfected with si RNA YAP compared with the corresponding cells transfected with si RNA NC(P<0.05).Conclusion:1?The m RNA and protein levels of YAP in A549 cell spheres were higher than A549 cells.2 ? Knockdown of YAP can reduce the resistance to cisplatin of A549 cell spheres.