title: Radioresponsive tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene therapy for malignant brain tumors.
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.
authors.affiliation: Department of Biomedical Engineering, Medical School, Johns Hopkins University, Baltimore, MD, USA. hideo-tsurushima@aist.go.jp
authors.forename: H
authors.initials: H
authors.lastname: Tsurushima
authors.forename: X
authors.initials: X
authors.lastname: Yuan
authors.forename: L E
authors.initials: LE
authors.lastname: Dillehay
authors.forename: K W
authors.initials: KW
authors.lastname: Leong
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000628:therapy; D045744:Cell Line, Tumor; D053672:Electrochemotherapy; D015316:Genetic Therapy; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000235:genetics*
chemical_list: D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human