Galectin-1 is implicated in the protein kinase C epsilon/vimentin-controlled trafficking of integrin-beta1 in glioblastoma cells

Brain Pathol. 2010 Jan;20(1):39-49. doi: 10.1111/j.1750-3639.2008.00227.x. Epub 2009 Oct 8.

Abstract

Cell motility and resistance to apoptosis characterize glioblastoma (GBM) growth and malignancy. In our current work we report that galectin-1, a homodimeric adhesion molecule and carbohydrate-binding protein with affinity for beta-galactosides, is linked with cell surface expression of integrin beta1 and the process of integrin trafficking. Using immunofluorescence, depletion of galectin-1 through both stable knockdown and transient-targeted small interfering RNA (siRNA) treatment induces an intracellular accumulation of integrin-beta1 coincident with a diminution of integrin-beta1 at points of cellular adhesion at the cell membrane. Galectin-1 depletion does not alter the gene expression level of integrin-beta1. Transient galectin-1 depletion effectuates as well the perinuclear accumulation of protein kinase C epsilon (PKCepsilon) and the intermediate filament vimentin, both of which have been shown to mediate integrin recycling in motile cells. Our results argue for the involvement of galectin-1 in the PKCepsilon/vimentin-controlled trafficking of integrin-beta1. The understanding of molecular mediators such as galectin-1 and the pathways through which they drive the cell invasion so descriptive of GBM is anticipated to reveal potential therapeutic targets that promote glioma malignancy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antisense Elements (Genetics)
  • Blotting, Western
  • Brain Neoplasms / metabolism*
  • Cell Line, Tumor
  • Endoplasmic Reticulum / metabolism
  • Galectin 1 / genetics*
  • Galectin 1 / physiology*
  • Gene Silencing
  • Genomics
  • Glioblastoma / metabolism*
  • Humans
  • Integrin alpha Chains / biosynthesis
  • Integrin beta1 / biosynthesis*
  • Integrin beta1 / genetics*
  • Neoplasm Proteins / analysis
  • Neoplasm Proteins / biosynthesis
  • Protein Kinase C-epsilon / physiology*
  • RNA, Small Interfering
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transfection
  • Vimentin / physiology*

Substances

  • Antisense Elements (Genetics)
  • Galectin 1
  • Integrin alpha Chains
  • Integrin beta1
  • Neoplasm Proteins
  • RNA, Small Interfering
  • Vimentin
  • integrin alpha9
  • Protein Kinase C-epsilon