Effect Of Tumor Necrosis Factor-related Apoptosis-inducing Ligand(TRAIL)combined With Schisandrin B(SchB)on The Growth Of Brain Tumor Stem Cells.

Brain malignant tumor is one of the most adult cancers with the highest mortality rate.Globally,the incidence of primary malignant brain tumors is increasing year by year and its prognosis is extremely poor.In recent years,it has been found that this is due to the existence of a small number of brain tumor stem cells(BTSCs)in brain tumors,which are the root of brain tumor occurrence and recurrence,but there is currently no effective treatment.Tumor necrosis factor related apoptosis-inducing ligand(TRAIL)can specifically recognize and bind to death receptors to induce programmed apoptosis,but has no obvious side effects on normal cells.Therefore TRAIL has become the focus of the anti-tumor field.Different types and different degrees of malignant glioma cells have different sensitivity to TRAIL.Previously,we found in the research that Schisandrin B(Sch B)can promote tumor cell apoptosis by activating mitochondrial pathway,and it can be confirmed that Schisandrin B can inhibit the growth of glioma in vivo and in vitro experiment.Whether TRAIL combined with Sch B has a synergistic inhibition or clearance effect on BTSCs is still unclear.BTSCs were obtained by CD133 immunomagnetic bead sorting after we cultured primary glioma cells.Thiazole blue(MTT)assay was used to detect the proliferation of BTSCs after treatment with TRAIL and Sch B alone or in combination.Both TRAIL and Sch B inhibited the proliferation of BTSCs in a concentration-dependent manner.Significant synergistic effects could occur when the two drugs were combined.Especially after the high concentration of TRAIL and Sch B work together with BTSCs,the proliferation of BTSCs can be inhibited by more than 50%.The apoptosis rate of BTSCs detected by Annexin V-PI double staining showed that TRAIL combined with Sch B could induce apoptosis of BTSCs.Western blotting detection of apoptosis-related proteins found that TRAIL combined with Sch B can increase the expression of Bax,Caspase-3?8 and activate the cleavage reaction by activating Caspase-3 and 8.These indicate that TRAIL and Sch B exert a good synergistic effect to induce apoptosis of BTSCs.