title: Ethyl acetate extracts of Fructus Ligustri Lucide induce cell apoptosis in human neuroglioma cell.
abstract: OBJECTIVE
  Previous studies have shown that Fructus Ligustri Lucide (FLL) can be used to improve the tumor cells sensitivity to chemotherapeutics and promote cell death. However, the mechanism by which FLL mediate this effect is unclear. In the present study, ethyl acetate extracts of FLL induced cell apoptosis in human neuroglioma cell was investigated.
  
  
  METHODS
  The cell viability was detected by the CCK8 assay. The cell apoptosis was assessed by annexin V-PI double-labeling staining and hoechst 33342 staining. The protein expression of cell cycle regulators and tumor suppressors were analyzed by western blotting.
  
  
  RESULTS
  Treatment of human neuroglioma cell with FLL induced cell death in a dose-and time-dependent manner by using CCK8 assay. Consistent with the CCK8 assay, the flow cytometry results showed that the proportion of the early and terminal phase of apoptosis cells had gained after FLL treatment as compared to untreatment group. Moreover, human neuroglioma cells were exposed to the ethyl acetate extracts of FLL for 48 h, which resulted in an accumulation of cells in G2/Mphase. Apoptotic bodies were clearly observed in human neuroglioma cells that had been treated with FLL for 48 h and then stained with Hochest 33342. The expression of Cyclin B1, CDC2 and cdc25C were downregulated upon FLL treatment in human neuroglioma cells. The expression level of Cyclin B1, CDC2 and cdc25C was negatively correlated with the time of treatment by FLL. In contrast, p53, p21 and p16 were obviously upregulated by FLL treatment in a time-dependent manner.
  
  
  CONCLUSIONS
  These results confirmed that FLL could induce apoptosis in human neuroglioma cells, the underlying molecular mechanisms, at least partially, through activation p21/p53 and suppression CDC2/cdc25C signaling in vitro.
authors.affiliation: Department of Neurosurgery, First Hospital of Jilin University Changchun 130021, China.
authors.forename: Yun-Bao
authors.initials: YB
authors.lastname: Guo
authors.affiliation: Operating Room, Central Hospital of Changchun Changchun 130011, China.
authors.forename: Yi-Meng
authors.initials: YM
authors.lastname: Shao
authors.affiliation: Department of Orthopedics, China-Japan Union Hospital of Jilin University Changchun 130033, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Neurosurgery, First Hospital of Jilin University Changchun 130021, China.
authors.forename: Song-Bai
authors.initials: SB
authors.lastname: Xu
authors.affiliation: Department of Anatomy, College of Basic Medical Sciences, Jilin University Changchun 130021, China.
authors.forename: Xing-Dong
authors.initials: XD
authors.lastname: Zhang
authors.affiliation: Department of Anatomy, College of Basic Medical Sciences, Jilin University Changchun 130021, China.
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Liu
keywords: CDC2/cdc25C; Fructus Ligustri Lucide; neuroglioma; p53/p21