Effect of N-acetyl-galactosaminotransferase 7 on proliferation and migration of prostate cancer cells and mechanism
Objective To investigate the effect of N-acetyl-galactosaminotransferase 7(GALNT7)on the proliferation and migration of prostate cancer cells and its molecular mechanism.Methods The cancer tissues of 30 patients with prostate cancer who underwent prostate surgery in the Department of Urology of Tianjin Fifth Central Hospital and the Affiliated Hospital of Yanbian University from January 2019 to January 2022 were selected as the research objects.Immunohistochemical staining,Western blot-ting and quantitative real-time polymerase chain reaction(qRT-PCR)were used to detect the expression level of GALNT7 in prostate cancer tissues.Cell counting kit-8(CCK-8)assay,BrdU incorporation assay and wound healing assay were used to detect cell migration,invasion and proliferation.VVA lectin pull-down assay and Western blotting were used to detect the effect of GALNT7 on the phosphorylation and O-GlcNAc modification of epidermal growth factor receptor(EGFR),and the expression level of EGFR/phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)signaling pathway.The differences between groups were analyzed by paired t-test or analysis of variance(ANOVA).Results The expression levels of GALNT7 protein and RNA in prostate cancer tissues(7.86±1.64,9.49±2.34)were significantly higher than those in adjacent tissues(0.98±0.25,0.99±0.33,t=13.080,11.390,P<0.05).CCK-8 assay showed that the proliferation ability of Ad-GALNT7 group was significantly higher than that of Ad-GFP group(1.14±0.35 vs.0.76±0.19,t=8.287,P<0.05).The BrdU positive rate in Ad-GALNT7 group was significantly higher than that in Ad-GFP group(42.36±5.19 vs.14.68±3.12,t=6.091,P<0.05).Scratch test showed that the migration and invasion ability of prostate cancer cells in the Ad-GALNT7 group was significantly higher than that in the Ad-GFP group(84.80±3.96 vs.58.34±2.19,t=11.860,P<0.05).Western blotting results showed that the phosphorylation of EGFR in the si-GALNT7 group was significantly lower than that in the si-GFP group(1.03±0.26 vs.2.68±0.57,t=3.693,P<0.05).VVA lectin pull-down assay showed that the level of EGFR O-GlcNAc glycosylation in si-GALNT7 group was significantly lower than that in si-GFP group(0.55±0.13 vs.1.00±0.27,t=4.570,P<0.05).Conclusion The expression of GALNT7 is significantly increased in prostate cancer,and it can modify EGFR through O-GlcNAc glycosylation,activate EGFR/PI3K/Akt signaling pathway,and promote the migration,invasion and proliferation of prostate cancer cells.