Role of CD44H carbohydrate structure in neuroblastoma adhesive properties

Med Pediatr Oncol. 2001 Jan;36(1):139-41. doi: 10.1002/1096-911X(20010101)36:1<139::AID-MPO1033>3.0.CO;2-Y.

Abstract

Background: CD44 represents a heterogeneous group of surface glycoproteins involved in cell-cell and cell-matrix interactions. CD44H is the major receptor for hyaluronate, and most if not all CD44H known functions are attributed to its ability to recognize hyaluronate. We have previously demonstrated a lack of CD44 expression in high stages and NMYC-amplified tumors and further have shown that NMYC-amplified cell lines either did not express CD44 at all or expressed a nonfunctional receptor. On the other hand, nonamplified cells constitutively expressed an active receptor, suggesting that absence of CD44-mediated hy aluronate binding could be related to increased malignancy in human neuroblastoma.

Procedure: In the present study we have compared the glycosylated structure of CD44 expressed by NMYC amplified vs. nonamplified cell lines in relation to their adhesive properties for hyaluronate. These adhesive properties were measured after modifications of the carbohydrate structure with enzymes and inhibitors of N- or O-linked glycosylation.

Results and conclusions: Our results indicate that increased sialylation, defective N-linked glycosylation, and substitution of the CD44 glycoprotein with keratan sulfate glycosaminoglycan might include modifications observed on neuroblastoma cells that could account for the inability of the receptor to bind hyaluronate.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 1-Deoxynojirimycin / pharmacology
  • Acetylgalactosamine / analogs & derivatives
  • Acetylgalactosamine / pharmacology
  • Blotting, Western
  • Carbohydrate Conformation
  • Cell Adhesion
  • Colonic Neoplasms / chemistry
  • Colonic Neoplasms / pathology
  • Gene Amplification
  • Genes, myc
  • Glycosylation / drug effects
  • Humans
  • Hyaluronan Receptors / chemistry
  • Hyaluronan Receptors / genetics
  • Hyaluronan Receptors / physiology*
  • Hyaluronic Acid / metabolism*
  • Molecular Weight
  • Neoplasm Proteins / chemistry
  • Neoplasm Proteins / genetics
  • Neoplasm Proteins / physiology*
  • Neuraminidase / pharmacology
  • Neuroblastoma / genetics
  • Neuroblastoma / metabolism
  • Neuroblastoma / pathology*
  • Protein Binding
  • Protein Processing, Post-Translational* / drug effects
  • Recombinant Fusion Proteins / metabolism
  • Transfection
  • Tunicamycin / pharmacology

Substances

  • Hyaluronan Receptors
  • Neoplasm Proteins
  • Recombinant Fusion Proteins
  • Tunicamycin
  • phenyl alpha-N-acetylgalactosaminide
  • 1-Deoxynojirimycin
  • Hyaluronic Acid
  • Neuraminidase
  • Acetylgalactosamine