Human brain tumors: multidrug-resistance P-glycoprotein expression in tumor cells and intratumoral capillary endothelial cells

Virchows Arch. 2007 Jul;451(1):81-7. doi: 10.1007/s00428-007-0401-z. Epub 2007 Jun 26.


Malignant brain tumor is a lethal disease with currently available treatment options having a limited impact on outcome. Nevertheless, novel therapeutic approaches combined with genetic prediction of chemosensitivity have, in the last decade, significantly improved clinical benefit for the treated patients. The fine characterization of the MDR1 gene encoding for P-glycoprotein (MDR1-Pgp) in brain tumors may be a crucial determinant for evaluating the long-term efficiency of specific anti-cancer compounds. By using a very high specific monoclonal antibody, the MDR1-Pgp was immunodetected in 34 out of 43 grade IV, 6 out of 10 grade III, 4 out of 7 grade II, and 1 out 3 grade I brain tumors. MDR1-Pgp resulted hyper-expressed, both in vessels and in neoplastic cells from the majority of tumors examined, compared to normal parenchyma. This study demonstrates that the MDR1 gene can be detected in all grade tumor brain malignancies and in endothelial cells of newly formed capillaries, thus, impairing drug access at the tumor cell level. Although the role of MDR1-Pgp in tumor blood vessels needs to be further examined and more clearly defined, drug resistance in malignant brain tumors may result from characteristics not only of tumor vasculature but also of neoplastic cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / analysis*
  • Adult
  • Aged
  • Aged, 80 and over
  • Brain Neoplasms / blood supply
  • Brain Neoplasms / chemistry
  • Brain Neoplasms / drug therapy*
  • Capillaries / chemistry
  • Drug Resistance, Neoplasm
  • Endothelial Cells / chemistry*
  • Female
  • Humans
  • Immunohistochemistry
  • Male
  • Middle Aged


  • ATP Binding Cassette Transporter, Subfamily B, Member 1