Comparative analyses of the N-glycoproteomes in HCT116 cancer cells and their non-tumorigenic DNMT1/3b double knockout (DKO1) cells and insight into the Mannose-6-phosphate pathway

Chen, M.; Assis, D. M.; Benet, M.; McClung, C. M.; Gordon, E.; Ghose, S.; Dupard, S. J.; Willetts, M.; Taron, C. H.; Samuelson, J. C.

doi:10.1101/2022.07.13.499654

bioRxiv · 10.1101/2022.07.13.499654

Comparative analyses of the N-glycoproteomes in HCT116 cancer cells and their non-tumorigenic DNMT1/3b double knockout (DKO1) cells and insight into the Mannose-6-phosphate pathway

Chen, M.·Assis, D. M.·Benet, M.·McClung, C. M.·Gordon, E.·Ghose, S.·Dupard, S. J.·Willetts, M.·Taron, C. H.·Samuelson, J. C.

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Abstract

N-glycoproteomic analyses provide valuable resources for investigation of cancer mechanisms, biomarkers, and therapeutic targets. Here, we mapped and compared the site-specific N-glycoproteomes of colon cancer HCT116 cells and isogenic non-tumorigenic DNMT1/3b double knockout (DKO1) cells using Fbs1-GYR N-glycopeptide enrichment technology and trapped ion mobility spectrometry. Many significant changes in site-specific N-glycosylation were revealed, providing a molecular basis for further elucidation of the role of N-glycosylation in protein function. HCT116 cells display hypersialylation especially in cell surface membrane proteins. Both HCT116 and DKO1 show an abundance of paucimannose and 80% of paucimannose-rich proteins are annotated to reside in exosomes. The most striking N-glycosylation alteration was the degree of mannose-6-phosphate (M6P) modification. N-glycoproteomic analyses revealed that HCT116 display hyper-M6P modification, which was orthogonally validated by M6P immunodetection. Significant observed differences in N-glycosylation patterns of the major M6P receptor, CI-MPR in HCT116 and DKO1 may contribute to the hyper-M6P phenotype of HCT116 cells.

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Chen, M., Assis, D. M., Benet, M., McClung, C. M., Gordon, E., Ghose, S., Dupard, S. J., Willetts, M., Taron, C. H., Samuelson, J. C.. 2022-07-13. Comparative analyses of the N-glycoproteomes in HCT116 cancer cells and their non-tumorigenic DNMT1/3b double knockout (DKO1) cells and insight into the Mannose-6-phosphate pathway. https://doi.org/10.1101/2022.07.13.499654

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