ABSTRACT
Objective:To investigate the effect of Schisandra chinensis polysaccharide(SCP)on the growth of brain tumor stem cells(BTSCs),and to clarify the mechanism of inhibiting the growth of BTSCs of SCP. Methods:The primary human glioma cells were cultured,then the BTSCs were isolated by CD133 immunomagnetic sorting.The neural stem cell surface markers CD133 and Nestin were detected by immunofluorescence assay.The proliferation rate of BTSCs was examined by MTT assay.Annexin V-PI analysis was used to analyze the apoptotic rate of BTSCs.The expression levels of Bax,Bcl-2 and Caspase-3 proteins in BTSCs in various groups were detected by ELISA assay.Results:The results of immunofluorescence staining showed that the expressions of CD133 and Nestin were positive in BTSCs.Compared with control group,the proliferation rates of BTSCs in 200,400 and 800 mg·L-1SCP groups were decreased,especially in 400 and 800 mg·L-1SCP groups(P<0.05).The results of Annexin V-PI analysis showed that the apoptotic rate of BTSCs in 800 mg·L-1SCP group was increased compared with control group(P<0.05).The ELISA results showed that the expression levels of Bax in 200,400 and 800 mg·L-1SCP groups were significantly increased(P<0.05),and the values of Bax/Bcl-2 were significantly increased(P<0.05);compared with control group,the Bcl-2 expression level in the BTSCs in 800 mg·L-1SCP group was decreased(P<0.05).The expression level of Caspase-3 protein in 800 mg·L-1SCP group was also significantly increased compared with control group(P<0.01).Conclusion:SCP could inhibit the growth of BTSCs,and the induction of apoptosis may be one of mechanisms.
ABSTRACT
Objective: To investigate the effect of Schisandra chinensis polysaccharide (SCP) on the growth of brain tumor stem cells (BTSCs), and to clarify the mechanism of inhibiting the growth of BTSCs of SCP. Methods: The primary human glioma cells were cultured, then the BTSCs were isolated by CD133 immunomagnetic sorting. The neural stem cell surface markers CD133 and Nestin were detected by immunofluorescence assay. The proliferation rate of BTSCs was examined by MTT assay. Annexin V-PI analysis was used to analyze the apoptotic rate of BTSCs. The expression levels of Bax, Bcl-2 and Caspase-3 proteins in BTSCs in various groups were detected by ELISA assay. Results: The results of immunofluorescence staining showed that the expressions of CD133 and Nestin were positive in BTSCs. Compared with control group, the proliferation rates of BTSCs in 200, 400 and 800 mg · L-1 SCP groups were decreased, especially in 400 and 800 mg · L-1 SCP groups (P<0.05). The results of Annexin V-PI analysis showed that the apoptotic rate of BTSCs in 800 mg · L-1 SCP group was increased compared with control group (P<0.05). The ELISA results showed that the expression levels of Bax in 200, 400 and 800 mg · L-1 SCP groups were significantly increased (P<0.05), and the values of Bax/Bcl-2 were significantly increased (P<0.05); compared with control group, the Bcl-2 expression level in the BTSCs in 800 mg · L-1 SCP group was decreased (P<0.05). The expression level of Caspase-3 protein in 800 mg · L-1 SCP group was also significantly increased compared with control group (P<0.01). Conclusion: SCP could inhibit the growth of BTSCs, and the induction of apoptosis may be one of mechanisms.
ABSTRACT
OBJECTIVE:To study the effect of Elemene emulsion combined with ganciclovir on invasive ability and TIMP-1 mRNA expression in C6 brain tumor stem cells. METHODS:Cells with 3 generations were isolated and cultured from rats'C6 ma-lignant glioma cell lines,and immunocytochemistry was adopted to detect the protein expressions of stem cell markers CD133,Nes-tin. 20 rats were randomly divided into blank control group(normal saline),ganciclovir group(intragastrically administrated,216 mg/kg),Elemene emulsion injection group (intravenously injected in tail,36 mg/kg) and combination group (intragastrically ad-ministrated 216 mg/kg of ganciclovir+intravenously injected 36 mg/kg of Elemene emulsion injection in tail),5 in each group, once every day,for 10 d. After 2 h of last administration,the blood of rats in each group was collected,serum was isolated and co-cultured 24 h with C6 BTSCs in in vitro culture medium. Boyden invasion test was used to detect the invasive ability of C6 BTSCs,and real-time quantitative polymerase chain reaction(RT-PCR)method was used to determine the TIMP-1 mRNA expres-sion of C6 BTSCs. RESULTS:Cells with 3 generations had obvious protein expressions in CD133 and Nestin,indicating they were BTSCs. Compared with blank control group,the cell invasion rates of C6 BTSCs in ganciclovir group,Elemene emulsion in-jection group and combination group were obviously decreased,TIMP-1 mRNA expression was obviously enhanced,with statisti-cal significances(P<0.05). Compared with ganciclovir group and Elemene emulsion injection group,the cell invasion rate of C6 BTSCs in combination group was obviously decreased,TIMP-1 mRNA expression was obviously enhanced,with statistical signifi-cances(P<0.05). CONCLUSIONS:Elemene emulsion injection combined with ganciclovir can obviously inhibit the cell invasion of C6 BTSCs,the mechanism may be associated with promoting the TIMP-1 generation,and combination use shows better effect than single use.
ABSTRACT
OBJECTIVE: To detect the effect of TRAIL on the growth of brain tumor stem cells, study the role of Caspase-8 and Bcl-2 of TRAIL resistance. METHODS: Brain tumor stem cells were isolated by CD133 magnetic sorting, and the positive rates of CD133+ cells were detected by flow cytometry, the self-renewing capicity of brain tumor stem cells was examined by subneurosphere formation assay, and the percentage of cell death were examined by MTS assay, the expression of DR5, FADD, Caspase-8 and Bcl-2 proteins was detected by Western blot. RESULTS: The positive rates of CD133+ cells were 71% after CD133 magnetic sorting. Brain tumor stem cells grow as neurosheres and have the abilities to reform neuroshperes, the capacity of neurosphere formation was significant increased after TRAIL treatment or not. Brain tumor stem cells were dead after TRAIL treatments, Caspase-8 and Caspases inhibitor can block the cell death that induced by TRAIL (P < 0.05). The expression of Caspase-8 protein was decreased and Bcl-2 protein was increased in brain tumor stem cells (P < 0.05). CONCLUSION: Brain tumor stem cells may response to TRAIL resistance, the reason is the lower expression of Caspase-8 protein and over expression of Bcl-2 protein which is unable to activate Caspase-8.
ABSTRACT
The tumor stem cell theory supposed that tumor stem cells are the origin of tumor abnormal proliferation,invasion,metastasis,drug resistance and recurrence.As the theory is put forward,it redefines the functions of classic stem cells in tumorigenesis.It is a great event for recent studies on glioma initiating cells as brain tumor stem cells were identified and isolated successfully.A lot of evidence from experiments in vivo and in vitro demonstrates that brain tumor stem cells might play an important role in glioma tumorigenesis.In this review,we discuss the relationship between tumor stem cells and tumorigenesis,and the research on the correlation between brain tumor stem cells and glioma genesis.