Objective: To investigate the effects and mechanism of tetrandrine on proliferation and apoptosis in multiple myeloma stem cells. Method: Methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay was used to detect the survival of cancer cell. Flow cytometer was used to detect the cell circles and apoptotic induced by tetrandrine. Western blot were used to detect the activity of cleaved-Caspase-3

cleaved-Caspase-9. Result: Compared with blank group and solution group

10

20

30

40 μmol·L-1 tetrandrine treatment for 6

12

24 h could significantly inhibit the proliferation of CD138-B cells (P<0.01). Compared with blank group and solution group

the cells in G0/G1 phase increased significantly (P<0.01)

and the cells in S phase significantly decreased (P<0.05

P<0.01)

when being treated with 30

40 μmol·L-1 tetrandrine. The apoptotic rate increased significantly at concentrations of 10

20

30

40 μmol·L-1of tetrandrine (P<0.01). Compared with blank group and solution group

the expression of cleaved-Caspase-3

cleaved-Caspase-9 protein was significantly increased after being treated with 20

30

40 μmol·L-1 tetrandrine (P<0.01)

the expression of cleaved-Caspase-3 protein was significantly increased when being treated with 10 μmol·L-1 tetrandrine (P<0.05). Conclusion: Tetrandrine can arrest CD138-B cell line in the G0/G1 phase

inhibit the cell survival

and enhance CD138-B cell apoptosis by promoting the activity of cleaved-Caspase-3

cleaved-Caspase-9.