Abstract: AIM: To explore whether the apoptosis was induced by matrine and its effect on the expression of Bcl-2 and proliferating cell nuclear antigen (PCNA) in human mutiple myeloma cell line RPMI8226 cells. METHODS: RPMI8226 cells were incubated with indicated concentrations of matrine. The growth of RPMI8226 cells was observed by CCK-8 colorimetric assay, and apoptosis rates were detected by flow cytometry using Annexin V-FITC PI staining. The cell cycles were analyzed by PI staining. Flow cytometry was used to detect the expression of Bcl-2 and PCNA. RESULTS: RPMI8226 cells viability in presence of matrine decreased markedly in a dose and time-dependent manner. The apoptosis could be induced by matrine and its level increased following the augmentation of the drug concentration. After treated by matrine for 48 h, a concentration-dependent increase of cells in G0 G1 phase and a decrease in S phase were detected, but there was no obvious change at G2 M phase. Treatment of RPMI8226 cells with matrine for 48 h provoked a decrease in the level of expression of Bcl-2 and PCNA. CONCLUSION: Matrine can significantly inhibit the growth of RPMI8226 cells, its function is performed by inducing apoptosis and arresting cell cycles. Bcl-2down-expression may probably function as an important regulator in the process of apoptosis induced by matrine.

Key words: matrine, RPMI8226 cell, apoptosis, cell cycle, Bcl-2