Journal of Jilin University Medicine Edition ›› 2015, Vol. 41 ›› Issue (02): 321-326.doi: 10.13481/j.1671-587x.20150223

Previous Articles     Next Articles

Elimination of temozolomide in combination with metformin on glioma stem cells and its mechanism

YU Zhiyun1, LI Yunqian1, CHEN Yong1, ZHAO Liyan2, LIU Huanbing1, WANG Nan1, WANG Bin1, CHEN Yunzhao1, ZHAO Gang1   

  1. 1. Department of Neurosurgery, First Hospital, Jilin University, Changchun 130021, China;
    2. Department of Clinical Laboratory, First Hospital, Jilin University, Changchun 130021, China
  • Received:2014-12-31 Online:2015-03-28 Published:2015-04-04

Abstract:

Objective To explore the effect of temozolomide (TMZ) in combination with metformin (MET) on the elimination of glioblastoma stem cells(GSCs) in vitro,and to clarify the mechanism.Methods The human glioma U87 cells were cultured in the neural stem cell medium,and the GSCs were identified by immunofluorescence methods;the GSCs were selected and were treated with control solution(control group), different concentrations of TMZ(TMZ group)and MET(MET group) or TMZ combined with MET(TMZ+MET group).The number of secondary neurospheres were counted under microscope, and the inhibitory rate of proliferation of GSCs was detected by CCK-8 assay;flow cytometry and Annexin Ⅴ and PI staining flow cytometry were used to detect the percentage of cell cycle and the apoptotic rate of GSCs,respectively.Results Compared with control group, the number of secondary neurospheres in TMZ+MET group was significantly decreased in a concentration-dependent manner;the number of secondary neurosphere in TMZ+MET group was significantly lower than those in TMZ group and MET group(P<0.01).Compared with control group, the inhibitory rates of the proliferation of GSCs in TMZ and MET groups were increased,the inhibitory rate of proliferation of GSCs in TMZ+MET group was higher than those in TMZ group and MET group(P<0.05),and the combination index(CI)<1.The flow cytometry results displayed that the percentage of the cells at G2/M phase in TMZ+MET group was significantly higher than those in TMZ group and MET group(P<0.05),and the apoptotic rate of GSCs in TMZ+MET group was significantly higher than those in TMZ group and MET group (P<0.05).Conclusion The combination of TMZ and MET can inhibit the serial self-renewal capability of GSCs as well as eliminate GSCs,and its mechanism may be related to the inhibition of the cell cycle progression of GSCs and induction of apoptosis.

Key words: temozolomide, metformin, glioblastoma stem cells, self-renewal

CLC Number: 

  • R730.264