End-binding 1 protein overexpression correlates with glioblastoma progression and sensitizes to Vinca-alkaloids in vitro and in vivo

Oncotarget. 2014 Dec 30;5(24):12769-87. doi: 10.18632/oncotarget.2646.

Abstract

End-binding 1 protein (EB1) is a key player in the regulation of microtubule (MT) dynamics. Here, we investigated the role of EB1 in glioblastoma (GBM) tumor progression and its potential predictive role for response to Vinca-alkaloid chemotherapy. Immunohistological analysis of the 109 human GBM cases revealed that EB1 overexpression correlated with poor outcome including progression-free survival and overall survival. Downregulation of EB1 by shRNA inhibited cell migration and proliferation in vitro. Conversely, EB1 overexpression promoted them and accelerated tumor growth in orthotopically-transplanted nude mice. Furthermore, EB1 was largely overexpressed in stem-like GBM6 that display in vivo a higher tumorigenicity with a more infiltrative pattern of migration than stem-like GBM9. GBM6 showed strong and EB1-dependent migratory potential. The predictive role of EB1 in the response of GBM cells to chemotherapy was investigated. Vinflunine and vincristine increased survival of EB1-overexpressing U87 bearing mice and were more effective to inhibit cell migration and proliferation in EB1-overexpressing clones than in controls. Vinca inhibited the increase of MT growth rate and growth length induced by EB1 overexpression. Altogether, our results show that EB1 expression level has a prognostic value in GBM, and that Vinca-alkaloid chemotherapy could improve the treatment of GBM patients with EB1-overexpressing tumor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain Neoplasms / drug therapy*
  • Brain Neoplasms / metabolism*
  • Brain Neoplasms / pathology
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • Disease Progression
  • Disease-Free Survival
  • Female
  • Glioblastoma / drug therapy*
  • Glioblastoma / metabolism*
  • Glioblastoma / pathology
  • Humans
  • In Vitro Techniques
  • Mice
  • Mice, Nude
  • Microtubule-Associated Proteins / biosynthesis*
  • Microtubule-Associated Proteins / genetics
  • Vinblastine / analogs & derivatives
  • Vinblastine / pharmacology
  • Vinca Alkaloids / pharmacology*
  • Vincristine / pharmacology
  • Xenograft Model Antitumor Assays

Substances

  • MAPRE1 protein, human
  • Microtubule-Associated Proteins
  • Vinca Alkaloids
  • vinflunine
  • Vincristine
  • Vinblastine