title: Disposition and gene expression characteristics in solid tumors and skeletal muscle after direct injection of naked plasmid DNA in mice.
abstract: Previous studies have suggested that direct injection of naked plasmid DNA (pDNA) into solid tumors can be a useful method for in vivo gene transfer into tumor cells. To gain more insight into this approach, we studied the disposition and gene expression characteristics of naked pDNA after intratumoral injection by direct comparison with those after intramuscular injection in mice. pDNA encoding reporter genes were directly injected into subcutaneous solid tumor models and skeletal muscles. Biodistribution studies using radiolabeled pDNA showed that the elimination of pDNA from the injection site was relatively fast and a part of the pDNA was absorbed from the lymphatic system after both local injections. Confocal microscopic studies using fluorescein-labeled pDNA demonstrated that pDNA distributed efficiently throughout the muscle tissue whereas pDNA localization in the tumor tissue was restricted. Characterization of gene expression clarified the variation in expression level between tumor preparations and some factors affecting the expression level in the tumor. Reporter gene expression was significantly inhibited by simultaneous administration of some polyanions in both cases, suggesting that a specific mechanism may be involved in the naked pDNA uptake by muscle and tumor cells. These findings provide useful information for direct naked pDNA delivery into solid tumors.
authors.affiliation: Department of Biopharmaceutics and Drug Metabolism, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kawase
authors.forename: Takehiko
authors.initials: T
authors.lastname: Nomura
authors.forename: Kei
authors.initials: K
authors.lastname: Yasuda
authors.forename: Naoki
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Hashida
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Takakura
mesh_terms: D000818:Animals; D015500:Chloramphenicol O-Acetyltransferase / Q000096:biosynthesis / Q000235:genetics; D004247:DNA / Q000008:administration & dosage*; D015870:Gene Expression; D018014:Gene Transfer Techniques; D017930:Genes, Reporter; D015552:Injections, Intralesional; D007273:Injections, Intramuscular; D008156:Luciferases / Q000096:biosynthesis / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D018482:Muscle, Skeletal / Q000378:metabolism*; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000378:metabolism*; D010957:Plasmids; D000071228:Polyelectrolytes; D011108:Polymers / Q000494:pharmacology; D013997:Time Factors
chemical_list: D015500:Chloramphenicol O-Acetyltransferase; D004247:DNA; D008156:Luciferases; D000071228:Polyelectrolytes; D011108:Polymers