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Updated: Aug 19, 2026

Metabolic Glycoengineering of Sialic Acid Using N-acyl-modified Mannosamines
12:06

Metabolic Glycoengineering of Sialic Acid Using N-acyl-modified Mannosamines

Published on: November 25, 2017

N-linked oligosaccharide processing and autocrine stimulation of tumor cell proliferation

I VanderElst1, J W Dennis

  • 1Samuel Lunenfeld Research Institute, Toronto, Ontario, Canada.

Experimental Cell Research
|February 1, 1991
PubMed

Insights

Branched N-linked oligosaccharides are crucial for cancer cell growth and metastasis. Inhibiting their processing slows tumor growth in vitro and in vivo, suggesting a therapeutic target for reducing cancer progression.

Area of Science:

  • Cancer Biology
  • Glycobiology
  • Tumorigenesis

Background:

  • Somatic mutations affecting N-linked oligosaccharide processing and chemical inhibitors can reduce tumor metastasis.
  • Complex N-linked oligosaccharides are common in malignant cells and may play a role in tumor progression.

Purpose of the Study:

  • To investigate the role of branched complex-type N-linked oligosaccharides in the growth and metastatic potential of MDAY-D2 tumor cells.
  • To determine if impaired oligosaccharide processing affects autocrine growth factor signaling and in vivo tumor growth.

Main Methods:

  • Generation and characterization of glycosylation mutants of the MDAY-D2 cell line.
  • Assessment of cell growth rates in serum-free medium (SFM) and serum-containing medium.
  • Treatment with the N-linked processing inhibitor swainsonine.
  • Analysis of autocrine growth factor activity in conditioned medium.
  • Correlation of in vitro growth rates with in vivo subcutaneous tumor growth.

Main Results:

  • Glycosylation mutants with truncated or less branched N-linked oligosaccharides exhibited slower growth in SFM but not in serum-containing medium.
  • Swainsonine treatment reduced cell growth in SFM, and both mutants and swainsonine-treated cells showed reduced responsiveness to autocrine growth factors.
  • In vivo tumor growth rates correlated with in vitro growth rates in SFM.

Conclusions:

  • Branched complex-type N-linked oligosaccharides are essential for optimal autocrine-dependent growth of MDAY-D2 cells in SFM.
  • These oligosaccharides are required for efficient response to autocrine growth factors.
  • The findings suggest that branched N-linked oligosaccharides are a significant factor in tumor progression in vivo.

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