CDH1 and gastric cancer: Overall, this study proposes a newly identified mechanism of E-cadherin (dys)regulation in cancer that is precisely coordinated through the interplay between O-mannosylation and N-glycosylation machinery that operates at the protein site-specific level Moreover, these differential patterns of E-cadherin glycosylation can constitute promising (glyco)biomarkers for improving gastric cancer patients' clinical management.