title: Nonviral gene therapy in vivo with PAM-RG4/apoptin as a potential brain tumor therapeutic.
abstract: BACKGROUND
  Glioma is still one of the most complicated forms of brain tumor to remove completely due to its location and the lack of an efficient means to specifically eliminate tumor cells. For these reasons, this study has examined the effectiveness of a nonviral gene therapy approach utilizing a tumor-selective killer gene on a brain tumor xenograft model.
  
  
  RESULTS
  The therapeutic apoptin gene was recombined into the JDK plasmid and delivered into human brain tumor cells (U87MG) by using a polyamidoamine dendrimer with an arginine surface (PAM-RG4). Studies in vitro showed that the PAM-RG4/apoptin plasmid polyplex exhibited a particularly high transfection activity of .40%. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, 4',6-Diamidino-2-phenylindole (DAPI) TUNEL assay, DAPI staining, and caspase-3 activity assay verified that the tumor cells had undergone apoptosis induced by apoptin. For in vivo studies, the polyplex was injected into tumors, which were induced by injecting U87MG cells intradermally into nude mice. Based on hematoxylin and eosin staining, epidermal growth factor receptor immunohistochemistry results and tumor volume measurement results, tumor growth was effectively inhibited and no specific edema, irritation, or other harm to the skin was observed after polyplex injection. The in vivo expression of apoptin and the induction of apoptosis were verified by reverse-transcription polymerase chain reaction analysis, TUNEL assay, and DAPI staining.
  
  
  CONCLUSIONS
  The PAM-RG4/apoptin gene polyplex is a strong candidate for brain tumor therapeutics because of the synergistic effect of the carrier's high transfection efficiency (35%-40%) in glioma cells and the selective apoptosis-inducing activity of apoptin in tumor cells.
authors.affiliation: Department of Chemistry, Seoul National University, Seoul, Republic of Korea.
authors.forename: Songhie
authors.initials: S
authors.lastname: An
authors.forename: Kihoon
authors.initials: K
authors.lastname: Nam
authors.forename: Sunghyun
authors.initials: S
authors.lastname: Choi
authors.forename: Cheng Z
authors.initials: CZ
authors.lastname: Bai
authors.forename: Yan
authors.initials: Y
authors.lastname: Lee
authors.forename: Jong-Sang
authors.initials: JS
authors.lastname: Park
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000737:chemistry; D017209:Apoptosis / Q000187:drug effects; D001120:Arginine / Q000008:administration & dosage* / Q000737:chemistry; D001932:Brain Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D036022:Capsid Proteins / Q000008:administration & dosage / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D050091:Dendrimers / Q000008:administration & dosage* / Q000737:chemistry; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D020287:In Situ Nick-End Labeling; D051379:Mice; D008819:Mice, Nude; D011897:Random Allocation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection / Q000379:methods; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; D036022:Capsid Proteins; D050091:Dendrimers; C104700:PAMAM Starburst; C091717:VP3 protein, Chicken anemia virus; D001120:Arginine
keywords: PAM-RG4; apoptin; apoptosis; malignant glioma; nonviral gene therapy