ABSTRACT
OBJECTIVE: To investigate the apoptosis of CD34+CD38--KG1a leukemia stem cells induced by Qinba selenium-mushroom extract(FA-2-b-ß), and its related mechanism. METHODS: CD34+CD38---KG1a cells were isolated from KG1a cell line by magnetic activated cell sorting. The proliferation ability of KG1a stem cells treatd by various concentration of FA-2-b-ß(1.2-2.4 mg/ml) in vitro for 24 and 48 hours were tested by cell counting Kit-8(CCK8). Flow cytometry was used to detect the apoptosis rate of KG1a stem cells in each group after treated by FA-2-b-ß in vitro. Expression of BAX,BCL-2,Casepase-3 and Cyclin D1 protein were detected by Western blot. RESULTS: The proportion of CD34+CD38---KG1a stem cells was (95.35±2.63ï¼% after immunomagnetic isolation. The proliferation of KG1a stem cells was inhibited significantly by FA-2-b-ß, which shows a time- and dose-dependent manner (24 h,r=0.943; 48 h,r=0.976). Flow cytometry shows that with the increasing of drug concentration, the apoptosis was also increased, when KG1a stem cells was treated by FA-2-b-ß for 24 h. Western blot indicated that the expression of apoptosis-related protein BAX and Casepase-3 were up-regulated, the expression of BCL-2 and Cyclin D1 were down-regulated. CONCLUSION: FA-2-b-ß can regulate proliferation and apoptosis KG1a stem cells, the involved mechanism may be related with the activation of mitochondrial-mediated apoptotic pathway.