Abstract
The epithelial-mesenchymal transition (EMT) is an essential step in the proliferation and metastasis of solid tumor cells, and glycosylation plays a crucial role in the EMT process. Certain aberrant glycans have been reported as biomarkers during bladder cancer progression, but global variation of N-glycans in this type of cancer has not been previously studied. We examined the profiles of N-glycan and glycogene expression in transforming growth factor-beta (TGFβ)-induced EMT using non-malignant bladder transitional epithelium HCV29 cells. These expression profiles were analyzed by mass spectrometry, lectin microarray analysis, and GlycoV4 oligonucleotide microarray analysis, and confirmed by lectin histochemistry and real-time RT-PCR. The expression of 5 N-glycan-related genes were notably altered in TGFβ-induced EMT. In particular, reduced expression of glycogene man2a1, which encodes α-mannosidase 2, contributed to the decreased proportions of bi-, tri- and tetra-antennary complex N-glycans, and increased expression of hybrid-type N-glycans. Decreased expression of fuca1 gene, which encodes Type 1 α-L-fucosidase, contributed to increased expression of fucosylated N-glycans in TGFβ-induced EMT. Taken together, these findings clearly demonstrate the involvement of aberrant N-glycan synthesis in EMT in these cells. Integrated glycomic techniques as described here will facilitate discovery of glycan markers and development of novel diagnostic and therapeutic approaches to bladder cancer.
Highlights
Glycans play important roles in protein folding, cell-cell adhesion, host-pathogen interactions, and cell signaling
HCV29 in normal medium had flattened epithelial morphology, while TGFβ-treated cells were converted to fibroblastic morphology (Figure 1A)
Treatment of HCV29 cells with TGFβ resulted in significantly increased expression of N-cadherin, vimentin, and fibronectin relative to control cells (Figure 1C)
Summary
Glycans play important roles in protein folding, cell-cell adhesion, host-pathogen interactions, and cell signaling. The study of glycans is inherently more complicated than that of nucleic acids and proteins, due to their more complicated structures [1]. Unlike the situation for nucleic acids and proteins, there is neither practical automatic synthesis nor high throughput sequencing techniques available for glycans, despite the great efforts and advances made in the synthetic/analytical chemistry of glycans. The sequencing of glycan structures has been focused on high resolution mass spectrometry (MS), which has produced an enormous amount of information on glycomics [2,3,4], the currently available structural information is often partial and detailed analysis requires significant instrumentation and expertise. A class of proteins found in plants, bacteria, fungi, and animals that are known to bind specific oligosaccharide moieties, were used for the structural elucidation of mammalian glycans on glycoproteins [5]. The applications of lectins, including affinity enrichment, microarrays, immunohistochemistry, blotting, electrophoresis, and ELISA have been developed and used widely in the last decade [6,7,8,9,10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
