Objective: To investigate the effects and mechanism of matrine modification X on inducing apoptosis of human nasopharyngeal carcinoma CNE1 cells in vitro. Method: MTT assay was used to measure the anti-proliferative effect of modification X on CNE1.The cell apoptosis rates and cell cycle were analyzed by flow cytometry. The protein expression of Bax

Bcl-2 and p53 was examined by Western blot. Result: After incubation of CNE1 cells with modification X for 48 h

the modification X could inhibit the proliferation of CNE1 cells with a dose dependent manner. Flow cytometry analysis revealed the apoptosis rate in 58

116 μmol·L-1 modification X group was higher than the matrine group by 70.02% and 75.73% respectively

which showed the significant difference compared with the control group (P<0.05

P<0.01). Compared with the control group

Modification X could significantly arrest the cell cycle at G1 stage (P<0.05

P<0.01). Western blot showed that the expression of Bax and p53 protein significantly increased by modification X in CNE1 cells

at the same time

the expression of Bcl-2 significantly decreased by modification X with a concentration dependent manner(P<0.05

P<0.01). Conclusion: Modification X could induce apoptosis of CNE1 cells in vitro

and the possible mechanism is related to arresting the cell cycle

increasing the Bax and p53 protein expression level and decreasing the Bcl-2 protein expression level.