Integration and long-term expression in xenografted human glioblastoma cells using a plasmid-based transposon system.
Gene therapy has the potential to become an effective component of cancer treatment by transferring genes that cause immunomodulation or tumor cell death or that inhibit angiogenesis into tumor cells or tumor-associated stroma. Viral vectors have been the primary gene transfer vehicles used for intratumoral gene transfer to date. Plasmid-based vectors may be safer and more scalable than viral vectors. However, attempts at plasmid-based intratumoral gene transfer have been met with transient expression and poor gene transfer efficiency. Here we report integration and long-term expression of reporter genes in human glial tumors, growing in nude mice, using the Sleeping Beauty (SB) transposon system. A two-plasmid system was used, in which linear polyethylenimine was complexed with a GFP, NEO, or luciferase transposon plasmid and a SB transposase-expressing plasmid. SB-mediated transposition led to chromosomal integration of the NEO transgene in roughly 8% of tumor cells. SB-mediated insertions were cloned from the genomes of glial tumor cells to provide molecular proof of transposase-mediated integration. Luciferase studies showed that SB facilitated long-term expression of the transgene in glial tumors. SB-mediated intratumoral gene transfer is a novel, nonviral technique that could be used to augment conventional therapy for glioblastoma or other cancers.
Department of Genetics, Cell Biology, and Development, University of Minnesota, and University of Minnesota Cancer Center, Arnold and Mabel Beckman Center for Transposon Research, Minneapolis, MN 55455, USA.
John R
JR
Ohlfest
Paul D
PD
Lobitz
Scott G
SG
Perkinson
David A
DA
Largaespada
D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D004251:DNA Transposable Elements / Q000235:genetics*; D005260:Female; D015870:Gene Expression / Q000235:genetics; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics; D005839:Gentamicins / Q000494:pharmacology; D005909:Glioblastoma / Q000737:chemistry / Q000378:metabolism* / Q000628:therapy; D049452:Green Fluorescent Proteins / Q000032:analysis / Q000235:genetics; D006801:Humans; D008156:Luciferases / Q000032:analysis / Q000235:genetics; D051379:Mice; D008819:Mice, Nude; D008969:Molecular Sequence Data; D010957:Plasmids / Q000737:chemistry / Q000235:genetics*; D011094:Polyethyleneimine / Q000737:chemistry; D019895:Transposases / Q000235:genetics / Q000378:metabolism*; D023041:Xenograft Model Antitumor Assays
D004251:DNA Transposable Elements; D005839:Gentamicins; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D011094:Polyethyleneimine; C010680:antibiotic G 418; D008156:Luciferases; D019895:Transposases; C494471:sleeping beauty transposase, human