Experimental study on the regulation of proliferation,apoptosis,and 5-FU sensitivity in gastric cancer cells by plumbagin through the PI3K/AKT/mTOR pathway

XU Mingxing; JIANG Hongmei

doi:10.3969/j.issn.1009-0460.2025.11.002

Abstract：Objective To explore the role of the phosphatidy linositol 3-kinase(PI3K)/protein kinase B(AKT)/mammalian target of rapamycin(mTOR)signaling pathway in the regulation of human gastric cell proliferation,apoptosis and 5-FU sensitivity by plumbagin(Plu).Methods Human gastric cancer cell line AGS was used as the research object.The cells were treated with low-dose Plu(2.5 μmol/L),high-dose Plu(5 μmol/L),and high-dose Plu combined with PI3K/AKT/mTOR pathway activator 740Y-P in vitro,with DMSO-treated cells serving as the control group.MTT assay,EdU staining and cell clone formation assay were used to detect cell proliferation ability.Annexin V-PI staining method was used to detect apoptosis in AGS cells.Western blotting was used to detect the protein expression and phosphorylation levels of key components in the PI3K/AKT/mTOR pathway in AGS cells.The 5-FU-resistant cell line AGS-R was induced and screened by the concentration-increasing method.After intervention with Plu and 740Y-P respectively,the changes in the resistance of AGS-R to 5-FU were detected to reflect the drug resistance of the cells.Results Compared with the control group,low and high doses of Plu treatment significantly reduced the colony formation rate,EdU positivity rate,p-PI3K/PI3K,p-AKT/AKT,and p-mTOR/mTOR levels of AGS cells,and significantly increased the apoptosis rate(P<0.05).High-dose Plu combined with 740Y-P treatment significantly increased the colony formation rate,EdU positivity rate,p-PI3K/PI3K,p-AKT/AKT,and p-mTOR/mTOR levels of AGS cells,and significantly decreased the apoptosis rate(P<0.05).The resistance index of 5-FU resistant AGS cells was 4.95,and the reversal fold was 2.05(>1.5).Plu intervention significantly reduced the EdU positive rate of AGS-R cells and significantly increased the apoptosis rate(P<0.05).However,co-administration of a high-dose Plu with 740Y-P significantly reversed these changes(P<0.05).Conclusion Plu inhibits the proliferation of human gastric cancer cells by down-regulating the activity of the PI3K/AKT/mTOR pathway,promotes cell apoptosis,and enhances the sensitivity to 5-FU.