Effects of Ursolic Acid on Proliferation and Apoptosis of Human Pancreatic Cancer Cell PANC-1
Objective To investigate the effects of ursolic acid on the proliferation and apoptosis of human pancreatic cancer cell PANC-1.Methods PANC-1 cells were cultured with 1.25,2.5,5,10,25 and 50 μmol/L ursolic acid for 24,48 and 72 h,and the cell viability was measured by the methyl thiazolyl tetrazolium(MTT)method.PANC-1 cells were divided into the control group one(equal volume of dimethyl sulfoxide)and the ursolic acid low-,medium-and high-dose groups(5,10 and 20 μmol/L ursolic acid),the cell morphology was observed by microscope,the expression levels of phosphatidylinositol 3-kinase(PI3K),phosphorylated-protein kinase B(p-Akt),phosphorylated-mammalian target of rapamycin(p-mTOR),Cleaved Caspase-3,B-cell lymphoma-2(Bcl-2),Bcl-2-associated X(Bax)proteins were detected by the Western blot,and the cell proliferation was observed by the colony formation assay.PANC-1 cells were divided into the control group two(equal volume of dimethyl sulfoxide)and the ursolic acid group(10 μmol/L ursolic acid),the cell migration was observed by the wound healing assay after 48 and 72 h of culture.The interaction of ursolic acid with PI3K and Akt2 proteins was simulated by the molecular docking.Results As the concentration of ursolic acid increased,the viability of PANC-1 cells gradually weakened,with the half-inhibitory concentrations(IC50)of 7.89,6.26 and 5.06 μmol/L at 24,48 and 72 h,respectively.Compared with those in the control group one,the cell morphology in the ursolic acid low-,medium-and high-dose groups was abnormal,with the increase of concentration,the number of deformed cells increased,and the cell boundaries became blurred;the number of cells also significantly decreased(P<0.05).Compared with those in the control group one,the expression levels of Cleaved Caspase-3 and Bax proteins in each dose group of ursolic acid significantly increased;the expression level of Bcl-2 protein in the ursolic acid medium-and high-dose groups significantly decreased;the expression levels of p-mTOR protein in the ursolic acid low-,medium-and high-dose groups,p-Akt protein in the ursolic acid medium-and high-dose groups,and PI3K protein in the ursolic acid high-dose group significantly decreased(P<0.05).Compared with that in the control group two,the migration distance in the ursolic acid group shortened after 48 and 72 h of culture.The ursane triterpenoid structure of ursolic acid can enter into a hydrophobic pocket of PI3K and Akt2 competitively binding with adenosine triphosphate(ATP)and occupy the ATP binding site,thereby interfering with the binding of PI3K and Akt2 to ATP and inhibiting their activation.Conclusion Ursolic acid can inhibit the proliferation of PANC-1 cells and promote their apoptosis by inhibiting the activation of the PI3K/Akt/mTOR signaling pathway.
ursolic acidhuman pancreatic cancer cell PANC-1PI3K/Akt/mTOR signaling pathwayapoptosis