Overexpression of ST6GalNAcV, a ganglioside-specific alpha2,6-sialyltransferase, inhibits glioma growth in vivo

Research output: Contribution to journalArticle

Abstract

Aberrant cell-surface glycosylation patterns are present on virtually all tumors and have been linked to tumor progression, metastasis, and invasivity. We have shown that expressing a normally quiescent, glycoprotein-specific alpha2,6-sialyltransferase (ST6Gal1) gene in gliomas inhibited invasivity in vitro and tumor formation in vivo. To identify other glycogene targets with therapeutic potential, we created a focused 45-mer oligonucleotide microarray platform representing all of the cloned human glycotranscriptome and examined the glycogene expression profiles of 10 normal human brain specimens, 10 malignant gliomas, and 7 human glioma cell lines. Among the many significant changes in glycogene expression observed, of particular interest was the observation that an additional alpha2,6-sialyltransferase, ST6 (alpha-N-acetyl-neuraminyl-2,3-beta-galactosyl-1,3)-N-acetylgalactosaminide alpha2,6-sialyltransferase 5 (ST6GalNAcV), was expressed at very low levels in all glioma and glioma cell lines examined compared with normal brain. ST6GalNAcV catalyzes the formation of the terminal alpha2,6-sialic acid linkages on gangliosides. Stable transfection of ST6GalNAcV into U373MG glioma cells produced (i) no change in alpha2,6-linked sialic acid-containing glycoproteins, (ii) increased expression of GM2alpha and GM3 gangliosides and decreased expression of GM1b, Gb3, and Gb4, (iii) marked inhibition of in vitro invasivity, (iv) modified cellular adhesion to fibronectin and laminin, (v) increased adhesion-mediated protein tyrosine phosphorylation of HSPA8, and (vi) inhibition of tumor growth in vivo. These results strongly suggest that modulation of the synthesis of specific glioma cell-surface glycosphingolipids alters invasivity in a manner that may have significant therapeutic potential.

Details

Authors
  • Roger A Kroes
  • Huan He
  • Mark R Emmett
  • Carol L Nilsson
  • Franklin E Leach
  • I Jonathan Amster
  • Alan G Marshall
  • Joseph R Moskal
External organisations
  • Pfizer Inc. US
Research areas and keywords

Keywords

  • Animals, Biochemical Phenomena, Brain, Cell Adhesion, Cell Line, Cell Membrane, Fibronectins, Gangliosides, Genes, Glioma, Glycoproteins, Glycosylation, Humans, Mice, Mice, SCID, N-Acetylneuraminic Acid, Oligonucleotide Array Sequence Analysis, Phosphorylation, Sialyltransferases, Transfection, Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.
Original languageEnglish
Pages (from-to)12646-51
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume107
Issue number28
Publication statusPublished - 2010 Jul 13
Publication categoryResearch
Peer-reviewedYes
Externally publishedYes