A study on the mechanism of Ginkgo biloba leaf extract EGb761 improving sensitivity of colorectal cancer cells to cisplatin
NING Qiting
CHEN Xingmei
HUANG Shanpei
ZHU Liye
QIU Xinze
LIU Shiquan
Abstract：Objective To explore the mechanism of Ginkgo biloba leaf extract EGb761 improving sensitivity of colorectal cancer(CRC)cells to cisplatin(DDP).Methods Human CRC cells RKO were selected for experiment,and control group,EGb761 group,DDP group and EGb761+DDP group were set up according to different intervention methods.The cholecystokinin-8(CCK-8)method was used to detect the effects of EGb761 and DDP on the viability of RKO cells.Real-time fluorescent quantitative polymerase chain reaction(RT-qPCR)and Western blot experiments were used to detect the expressions of sphingosine kinase 1(SphK1)and apoptosis-related factor cysteinyl aspartate-specific proteinase 3(Caspase 3),and B-cell lymphoma 2(BCL2).Flow cytometry experiment was used to detect the apoptosis level of RKO cells.The RKO cell lines with low expression of SphK1 were constructed through lentiviral transfection,and the effects of knocking down SphK1 and EGb761 intervention on the expression levels of apoptosis-related factors were analyzed.The main active ingredients of Ginkgo biloba leaves were searched from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP),and their abilities to bind to SphK1 were explored through molecular docking.Results The results of CCK-8 experiment showed that EGb761 could inhibit the proliferation of RKO cells and enhance the sensitivity of RKO cells to DDP.The results of RT-qPCR experiment and Western blot experiment showed that compared with those in the control group,the mRNA and protein expression levels of Caspase 3 in the EGb761 group,the DDP group and the EGb761+DDP group were significantly increased(P＜0.05),and the mRNA and protein expression levels of Caspase 3 in the EGb761+DDP group were higher than those in the EGb761 group and the DDP group(P＜0.05).Compared with those in the control group,the mRNA and protein expression levels of BCL2 in the EGb761 group,the DDP group and the EGb761+DDP group were significantly decreased(P＜0.05),and the mRNA and protein expression levels of BCL2 in the EGb761+DDP group were lower than those in the EGb761 group and the DDP group(P＜0.05).The results of flow cytometry experiment showed that compared with the control group,the apoptosis rates in the EGb761 group,the DDP group and the EGb761+DDP group were significantly increased(P＜0.05),and the apoptosis rates in the EGb761+DDP group were higher than those in the EGb761 group and the DDP group(P＜0.05).EGb761 could inhibit the expression of SphK1 protein in the RKO cells,and the inhibitory effect was dose-dependent(P＜0.05).The RKO cell lines with low expression of SphK1 were successfully constructed by lentiviral transfection method.The experimental results showed that knocking down SphK1 could significantly enhance the sensitivity of RKO cells to DDP,while the actions of EGb761 on enhancing the sensitivity of RKO cells to DDP and promoting apoptosis depended on the inhibition of SphK1.The results of molecular docking showed that the main active ingredients of bilobalide,ranunculin,sesamin,(+)-catechin,(-)-catechin and isorhamnetin in Ginkgo biloba leaves had strong abilities to bind to SphK1.Conclusion Ginkgo biloba leaf extract EGb761 promotes apoptosis by inhibiting SphK1 expression,thereby enhancing the sensitivity of CRC cells to DDP.
Keywords：Ginkgo biloba leaf extractColorectal cancer(CRC)Sphingosine kinases 1(SphK1)Cisplatin(DDP)Chemosensitivity
Publication Date：2025-04-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 389-395 )