Inhibition of Sphk1 promotes the effect of oxaliplatin on colon cancer cells
- VernacularTitle:靶向阻断Sphk1促进奥沙利铂的抗结肠癌作用
- Author:
Zheng LI
1
;
Jiewei CAO
;
Bin LIU
Author Information
- Publication Type:Journal Article
- Keywords: Sphk1; colon cancer; oxaliplatin; drug resistance; sensitivity
- From: Journal of Xi'an Jiaotong University(Medical Sciences) 2025;46(3):435-441
- CountryChina
- Language:Chinese
- Abstract: Objective To detect the expression of sphingosine kinase 1(Sphk1)in colon cancer patients and colon cancer cells so as to explore the relationship between Sphk1 and oxaliplatin resistance in colon cancer.Methods The colon cancer RNA high-throughput sequencing data were downloaded from The Cancer Genome Atlas(TCGA),and the differences in Sphk1 expression in colon cancer tissues and normal tissues were analyzed.Human colon cancer SW48,HCT116,HT29 and LoVo cells were cultured,and the cells were randomly divided into blank control group,oxaliplatin group,transfected negative control siRNA group,transfected Sphk1 siRNA group,Sphk1 inhibitor dimethylsphingosine(DMS)group,and oxaliplatin and DMS combination group.Western blotting was used to detect the protein expressions of Sphk1 and phosphorylated Sphk1(p-Sphk1)in colon cancer cells.ELISA kits were used to detect Sphk1 activity and sphingosine-1-phosphate(S1P)content.MTT was used to detect the effect of oxaliplatin on cell viability.The nude mice planted tumor model of colon cancer cells was prepared and relevant interventions were performed.The tumor growth curve was drawn,and the expression of p-Sphk1 in the tumor was detected by Western blotting.Results The bioinformatics analysis of the colon cancer sequencing data in the TCGA database showed that the expression of Sphk1 in colon cancer tissues was significantly higher than that in normal tissues.Western blotting revealed that the expressions of Sphk1 and p-Sphk1 in HT29 and LoVo cells were higher than those in SW48 and HCT116 cells.ELISA detection found that the activity of Sphk1 in HT29 and LoVo cells was significantly higher than that in SW48 and HCT116 cells.MTT assay indicated that HT29 and LoVo cells showed drug resistance to oxaliplatin,and blocking the expression of Sphk1 with Sphk1 siRNA could restore the sensitivity of cells to oxaliplatin.Compared with the single application,the combined application of DMS and oxaliplatin could synergistically inhibit the viability of tumor cells,the activity of Sphk1 and the expression of S1P.In the nude mouse xenograft tumor models of colon cancer cells,the inhibitory effect of the combined administration of oxaliplatin and DMS on the growth of xenograft tumors was significantly stronger than the inhibitory effect of the single administration group,and it could synergistically reduce the expression of p-Sphk1 in the xenograft tumors and the concentration of S1P in the animal serum.Conclusion The expression and activation of Sphk1 are related to the sensitivity of colon cancer to oxaliplatin.Blocking Sphk1 can reverse the resistance of colon cancer cells to oxaliplatin and enhance the effects of oxaliplatin in vitro and in vivo.
