Mechanism Of Astragalus Polysaccharide Inhibited The Invasion Of Human Glioma U251 Cells Targeting Src-Cortactin Pathway

Invasion and metastasis are the main characteristics of malignant tumors and one of the important causes of death of tumor patients.Malignant primary central nervous system tumor is a heterogeneous tumor formed by central nervous system cells.Due to the difficulty of cutting normal human brain tissue and the characteristics of largearea infiltration,growth and development of malignant tumor cells into the brain,it is very difficult to completely remove it through surgery.Therefore,it is considered the most difficult cancer to treat by medical practitioners all over the world.In adults,the most common malignant brain tumor is glioma,which accounts for about 40% to 45%of all intracranial malignant tumors.Glioma cannot be completely treated by surgery,coupled with its resistance to radiotherapy and chemotherapy,it is more and more urgent to find the latest treatment strategy.In addition,the clinical treatment burden of malignant glioma will also increase,which is related to its diffuse and invasive growth,high recurrence rate and poor prognosis.How to reduce the damage of brain tissue,inhibit intracranial invasive growth and eliminate tumor to the greatest extent is still the goal of brain tumor research.Astragalus membranaceus has a long medicinal history.Astragalus polysaccharide(APS)is one of the most important medicinal ingredients in astragalus.It has anti-aging,treatment of diabetes and chronic diseases,antiviral,anti fibrosis,blood lipid lowering,antibacterial and anti radiation effects.It has been reported that APS can inhibit tumor cell proliferation,participate in cell cycle regulation,induce tumor cell apoptosis,reverse chemoresistance,participate in immune regulation and inhibit tumor metastasis.Therefore,the role of APS in glioma is worth exploring and studying.Purpose:To explore the effect of APS on the invasion of human glioma U251 cells,clarify the mechanism of APS inhibiting the invasion of human glioma U251 cells,provide new ideas for the treatment of glioma,and provide practical and theoretical basis for the clinical application of Astragalus polysaccharide.Methods and results:In this study,human glioma U251 Cell line was used for experimental study.1 To detect the effect of Astragalus Polysaccharide on the invasion of glioma cell line U251CCK-8 experiment was used to detect the cell viability,draw the proliferation curve and study the effect of APS on the proliferation of glioma cell U251.The results showed that when the concentration of APS was 100ug/ml and the action time was24 h,there was no significant difference in the cell proliferation between the dosing group(U251+APS)and the control group(U251).It was determined that the dosage of APS was 100ug/ml and the action time was 24 h in the follow-up invasion experiment.Transwell experiment was used to detect the cell invasion and study the effect of Astragalus Polysaccharide on the invasion of glioma cell U251.The results showed that the cell invasion ability of the dosing group(U251+APS)was reduced by86.74% compared with the control group(U251),indicating that APS had a inhibitory effect on the invasion of glioma cell U251.2 Effect of Astragalus Polysaccharides on the expression and phosphorylation of invasion related kinases FAK,Src and AktWestern Blotting experiment was used to detect the effect of Astragalus Polysaccharides on the expression and phosphorylation of invasion related kinases FAK,Src and Akt,and to explore the mechanism of APS inhibiting glioma cell invasion.The results showed that the expression of invasion related kinase Src in the dosing group(U251 + APS)was not significantly changed compared with the control group(U251),but the phosphorylation of Src in the dosing group was inhibited.3.Effects of Astragalus Polysaccharides on the expression and phosphorylation of invasion related protein CortactinWestern Blotting experiment was used to detect the effect of Astragalus Polysaccharide on the expression and phosphorylation of invasion related protein Cortactin.The results showed that compared with the control group(U251),the expression of Cortactin in the dosing group(U251+APS)had no significant change,but the phosphorylation level was inhibited,indicating that APS may regulate the phosphorylation level of Cortactin,so as to inhibit the invasion of glioma cells.4 Astragalus polysaccharide regulates glioma cell U251 invasion through SrcCortactin signal axisThe results showed that the phosphorylation level of Cortactin in the dosing group(U251 + APS)was inhibited compared with that in the control group(U251);After treatment with Src activator(U251 + APS + SA),the phosphorylation level of Cortactin recovered,which was not significantly different from that in the control group(U251).Transwell experiment detected the cell invasion.The results showed that after treatment with Src activator(U251 + APS + SA),the cell invasion ability recovered to no significant difference from the control group(U251).The above results showed that Astragalus Polysaccharide inhibited the invasion of glioma cell U251 through Src Cortactin signal axis.5.Effect of Astragalus Polysaccharides on the sensitivity of glioma cell line U251 to temozolomideCCK-8 experiment was used to detect the cell viability of glioma cell U251 treated with APS under the action of different concentrations of TMZ(1600um,800 um,400um,200 um and 100 um,3-pore).The results showed that APS enhanced the sensitivity of U251 cells to TMZ.Conclusion:1.Astragalus polysaccharide inhibits the invasion of glioma cell U251 through Src-Cortactin signal axis.2.Astragalus polysaccharide enhances the sensitivity of glioma cell line U251 to temozolomide.