西贝素通过调控Cyclin D1介导的CDK4/6-Rb-E2F1信号轴抑制人胃腺癌AGS细胞增殖OA

Objective:To investigate the anti-proliferative effect and molecular mechanism of sipeimine on human gastric adenocarcinoma cells(AGS)by modulating the Cyclin D1-mediated CDK4/6-Rb-E2F1 signaling axis.Methods:AGS and GES-1 cells were treated with different concentrations of sipeimine.The optimal inhibitory dose and duration were determined using CCK-8 and crystal violet assays.The effects of sipeimine on AGS cell migration and invasion were assessed via scratch and Transwell assays.Flow cytometry and Western blot analyses evaluated the impact of sipeimine on AGS cell cycle progression and expression of cell cycle-related proteins.Cyclin D1 was overexpressed by plasmid transfection to further elucidate the inhibitory mechanism of sipeimine via WB,crystal violet,scratch,and Transwell assays.An AGS xenograft nude mouse model was established to investigate the in vivo effects and mechanisms of sipeimine,and the expression of Cyclin D1,CDK4,CDK6,Rb,p-Rb,and E2F1 was assessed by immunofluorescence and immunohistochemistry.Results:Compared with the control group,sipeimine at a concentration of 100 μg/mL did not affect the proliferation of GES-1 cells(P>0.05),but significantly inhibited the proliferation,migration,and invasion capabilities of AGS cells(P<0.01).It also induced G0/G1 phase arrest in the AGS cell cycle and significantly suppressed the expression levels of the cycle-related proteins Cyclin D1,CDK4,CDK6,p-Rb,and E2F1(P<0.05 or P<0.01).Overexpression of Cyclin D1 significantly reduced the inhibitory effect of sipeimine on AGS cells(P<0.05 or P<0.01).In tumor-bearing mouse models,sipeimine inhibited AGS xenograft proliferation and affected the expression of Cyclin D1,CDK4,CDK6,p-Rb,and E2F1 in tumor tissues(P<0.01).Conclusion:Sipeimine may inhibit AGS proliferation by downregulating the Cyclin D1-mediated CDK4/6-Rb-E2F1 signaling pathway activation.