Empirical Study On Ursolic Acid Inducing Apoptosis In Human Nasopharyngeal Carcinoma Cell Line CNE-2Z

Objective: To investigate the mechanism of ursolic acid inducing the apoptosis of human nasopharyngeal carcinoma cell line CNE-2Z.Methods: CNE-2Z were treated by ursolic acid with different concentration. Cell proliferation was determined by MTT assay. Cell cycle and apoptosis rate were analysed by flow cytometry(FCM). The expressions of bax, bcl-2 and cox-2 were assessed by SP method of immunocytochemistry, while the expression of caspase 3 by Western blot.Result: 1,MTT:The 3 IC50 of CNE-2Z cells that were treated by ursolic acid for 24h,48h and 72h are 30.56μmol/L,31.94μmol/L and 33.06μmol/L.Ursolic acid inhibited the proliferation of CNE-2Z cells in dosage dependent manner(P<0.05). CNE-2Z cells that were treated by ursolic acid in 40-50μmol/L dosage almost ceased proliferating. 2,FCM: After treated by ursolic acid for 24 hours, the apoptosis rate of the CNE-2Z cells hightened with the increasing of the medicine density. It showed that the cell population reduced in S phase and cell cycle was arrested in G0/G1 phase. 3,Immunocytochemistry:The expression of bcl-2,bax and cox-2 can be shown in cell membrane and endochylema. With the increasing of the medicine density, the expression of bax was up-regulated in the apoptosis, while the expression of bcl-2 and cox-2 down-regulated. 4,Western blot:After treated by ursolic acid for 24 hours, With the increasing of the medicine density, the expression of caspase 3 was strengthened.Conclusion: Ursolic acid can induce apoptosis of CNE-2Z in vitro. Its molecular mechanism probably is through promoting activate-ion of caspase-3, up-regulating the expression of bax, and down-re-gulating the expressions of bcl-2 and cox-2.