?-bisabolol Inhibits Migration And Invasion Of Glioblastoma Cells By Blocking C-Met

Background and purposeGlioma accounts for about 32%of all primary tumors in the central nervous system and 81%of central nervous system malignancies.It is also the most common intracranial malignancy.Glioma originates from neuroepithelial tissue,it has the characteristics of high incidence,high recurrence rate,rapid growth and poor prognosis,especially glioblastoma,which invades the surrounding tissues and has high degree of malignancy,making it almost impossible to do complete resection.With the current plan of surgery combined with comprehensive radiotherapy and chemotherapy,the median survival time of the patients is only 1 year,which poses a serious threat to human health.The mechanism of c-Met molecules involved in the development of tumor and the mechanism of promoting tumor invasion and migration have been studied.In many malignancies,including glioblastoma,c-Met is overexpressed,which up-regulates the expression of matrix metalloproteinase(MMP)gene,reconstructs intercellular substance,and paves the way for tumor invasion.On the other hand,it participates in the epithelial-mesenchymal transition(EMT)through the positive feedback regulation of the transcription factor TWIST to provide a driving force for tumor invasion.a-Bisabolol is a bioactive substance derived from essential oils such as chamomile.It has good fat-soluble properties.Previous studies have shown that it has certain anti-oxidation,anti-inflammatory,anti-mutation,immune regulation and other effects.In recent years,some studies have found that it has anti-tumor activity and has a highly effective killing effect on glioblastoma cells.However,the effect of this molecule on the migration and invasion of glioblastoma cells has not been reported.This study is to investigate the effects of ?-bisabolol on the invasion and migration of glioblastoma cells and the role of c-Met pathway.Methods1.CCK8 colorimetric assay detects the inhibitory effect of a-bisabolol on U87 and U251 cells.2.Wound healing test to detect the effect of a-bisabolol on the migration of U87 and U251 cells.3.Transwell assay to detect the effect of a-bisabolol on the invasion of U87 and U251 cells.4.Western blotting was used to detect the expression of c-Met and its downstream molecules MMP-2 and MMP-9 in the inhibition of migration and invasion of U87 and U251 cells by a-bisabolol.5.U251 cells were transfected with c-Met overexpression plasmid and a-bisabolol was continued to treat the cells.The cell migration ability was determined by the wound healing test.The cell invasion ability was detected by transwell assay.The expression of c-Met and its downstream molecular MMP-2 and MMP-9 was detected by Western blotting.6.Statistical analysisThe measured results for homogeneity of normality and variance was tested using SPSS 23.0 statistical software.A two-sample t-test was used for comparison between the two groups(if the control group was a constant,the confidence interval method was used);multiple-group comparisons were performed using one-way analysis of variance.If the variances were homogeneous,the comparisons between groups were compared using LSD tests.If the variance was not homogeneous,selected Dunnett T3 test.The test level was ? = 0.05,if P<0.05,the difference was statistically significant.Results1.a-Bisabolol induces proliferation inhibition of glioblastoma cells.With the increasing concentration of a-bisabolol,the survival rate of U87 and U251 cells decreased gradually,and the difference between the groups was statistically significant(P<0.05).2.a-Bisabolol can inhibit the migration and invasion of glioblastoma cells.Through the wound healing test,we found that a-bisabolol can significantly inhibit the migration of glioma cells U87 and U251 to the wound,and has a significant concentration dependence.The difference was statistically significant(P<0.05).Through transwell experiments,we found that after 24 hours of administration of different concentrations of a-bisabolol to glioblastoma cells,the number of cells shuttled to the lower chamber in the dosing group was significantly decreased compared with the control group,in a concentration-dependent manner.The difference was statistically significant(P<0.05).3.?-Bisabolol can down-regulate the expression of c-Met and its downstream molecules MMP-2 and MMP-9 in a concentration-dependent manner.The difference was statistically significant(P<0.05).4.Overexpression of c-Met partially reversed the inhibitory effect of a-bisabolol on glioblastoma cells.1)The migration ability of U251 cells transfected with c-Met overexpression plasmid group was higher than that of transfected with empty plasmid group,and the wound healing rate was significantly higher than that of the control group(P<0.05)..2)Transwell assay showed that the invasive ability of c-Met overexpression cells was increased,and the number of cells shuttled to the lower chamber was significantly larger than that of the empty plasmid group(P<0.05).3)Western blotting analysis showed that the expression of c-Met,MMP-2 and MMP-9 in the c-Met overexpression group was significantly higher than that in the empty plasmid group(P<0.05).