Radioresponsive tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene therapy for malignant brain tumors

Cancer Gene Ther. 2007 Aug;14(8):706-16. doi: 10.1038/sj.cgt.7701065. Epub 2007 Jun 1.

Abstract

Patients with malignant gliomas have a very poor prognosis. To explore a novel and more effective approach for the treatment of malignant gliomas, a strategy that combined tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene therapy and radiation treatment (RT) was designed in this study. Plasmid pE4-GFP was constructed by including the radioinducible early growth response gene 1 (Egr-1) promoter, and it yielded the best response with fractionated RT. Plasmid pE4-TRAIL was constructed by including the Egr-1 promoter and evaluated using U251 and U87 glioma cells. In the assay of apoptosis and killing activities, pE4-TRAIL exhibited radioresponse. pE4-TRAIL combined with RT is capable of inducing cell death synergistically. The expression of TRAIL death receptors was evaluated; which may be influenced by RT. Glioma cells with wild-type p53 showed upregulated expression of death receptors, and more synergistic effects on killing activities are expected. pE4-TRAIL was transfected into the subcutaneous U251 glioma cells in nude mice by the in vivo electroporation method. In the mice treated with pE4-TRAIL and RT, apoptotic cells were detected in pathological sections, and a significant difference of tumor volumes was observed when compared with the other groups (P<0.001). Our results indicate that radioresponsive gene therapy may have great potential as a novel therapy because this therapeutic system can be spatially or temporally controlled by exogenous RT and provides specificity and safety.

MeSH terms

  • Animals
  • Brain Neoplasms / pathology
  • Brain Neoplasms / radiotherapy*
  • Brain Neoplasms / therapy
  • Cell Line, Tumor
  • Electrochemotherapy
  • Genetic Therapy*
  • Humans
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • TNF-Related Apoptosis-Inducing Ligand / genetics*

Substances

  • TNF-Related Apoptosis-Inducing Ligand
  • TNFSF10 protein, human