Abnormal N-glycosylated CPXM1 promotes gastric cancer metastasis through ITGB2 / FAK pathway

Abstract Background: To explore the molecular mechanism of CPXM1 in gastric cancer (GC) metastasis.Methods: Based on the difference in expression of CPXM1 mRNA in GC tissues and normal gastric mucosa tissues in public databases, rt-PCR, WB and IHC staining experiments were performed to verify the expression of CPXM1 in fresh GC tissues. Bioinformatics analysis predicts the possible signal pathways of co-expression genes in CPXM1 overexpression group. The malignant phenotypes of GC cells was verified by in vivo and in vitro experiments. Using tunicamycin to inhibit the N-glycosylation of CPXM1 and constructing mutations. The plasmid further validated the specific N-glycosylation sites that affect the malignant phenotype of gastric cancer cells.Results: CPXM1 mRNA expression was significantly increased in GC tissues. The results of IHC staining and WB indicated that there was no difference in the expression of CPXM1 at the protein level. Knocking down CPXM1 expression in HGC-27 cells can significantly inhibit its migration and invasion ability. Increasing the expression of CPXM1 in MGC-803 and BGC-823 cell lines can significantly promote its migration and invasion capabilities. CPXM1 can also promote the adhesion of GC cells and change the cytoskeleton structure. The results of in-vivo experiments show that CPXM1 can promote the metastasis of GC cells in the abdominal cavity of nude mice. Bioinformatics analysis showed that the co-expressed genes of the CPXM1 high expression group were mainly enriched in cell adhesion function, and the experimental results verified that CPXM1 may promote the adhesion and metastasis of gastric cancer cells through the ITGB2/FAK signaling pathway. Through N-glycosylation site prediction and WB results, it was found that CPXM1 had abnormal N-glycosylation in GC tissues. Tunicamycin can reverse the ability of CPXM1 that promote the invasion of GC cells. After respectively mutating the N-glycosylation sites on CPXM1, it was found that N210 site is the key site for CPXM1 to promote the adhesion and invasion of GC cells.Conclusion: CPXM1 is upgraded in GC. CPXM1 can promote the adhesion, migration and invasion of GC cells and change cytoskeleton structure. The N210 site on CPXM1 is a key site affecting the malignant phenotype of GC.