GlycoSS: A DNA Glycosignal Sieve for Deciphering Spatially Resolved EpCAM-Specific Glycoforms

Malignant transformation of cancer is often accompanied by aberrant glycopatterns. Epithelial-mesenchymal transition (EMT) is a crucial biological process in cancer migration and invasion, accelerating cancer deterioration. High-precision analysis of protein-glycan spatial profiling in the EMT process is essential for elucidating glycosylation functions and cancer progression. However, the diversity of glycans in composition and conformation complicates their spatial analysis. Here, we develop a DNA glycosignal sieve (GlycoSS) visualization platform for screening glycoform expression with a protein spatial dimension. GlycoSS utilizes protein-anchored DNA nanoscanners of distinct lengths to control glycosignal readout, enabling protein-glycan distance modulations, and simultaneously orthogonally amplify glycoform output through signal amplification by an exchange reaction. Using GlycoSS, we screened EpCAM-specific hypoglycosylated glycoform signals in different breast cancer cell subtypes, especially characterizing the spatial distribution of glycans on the MCF-7 cell surface. Considering that the EpCAM-specific N-glycan dysregulation in EMT is pivotal, GlycoSS revealed dynamic glycan fluctuations during IGF-1-induced EMT, revealing that the N-glycans were positively associated with tumor malignancy and metastasis. GlycoSS is anticipated to accelerate the identification of aberrant N-glycosylation in tumor progression, advancing systemic glycobiology insights. Notably, GlycoSS is capable of analyzing diverse glycoprotein profiles, offering additional dimensions into the role of glycoprotein nanoenvironments in regulating membrane protein function.