Ex-vivo gene therapy of human vascular bypass grafts with E2F decoy: the PREVENT single-centre, randomised, controlled trial.
BACKGROUND
Cell-cycle blockade by ex-vivo gene therapy of experimental vein grafts inhibits the neointimal hyperplasia and subsequent accelerated atherosclerosis that lead to human bypass-graft failure. In a prospective, randomised, controlled trial, we investigated the safety and biological efficacy of intraoperative gene therapy in patients receiving bypass vein grafts.


METHODS
We studied gene therapy that uses decoy oligodeoxynucleotide, which binds and inactivates the pivotal cell-cycle transcription factor E2F. 41 patients were randomly assigned untreated (16), E2F-decoy-treated (17), or scrambled-oligodeoxynucleotide-treated (eight) human infrainguinal vein grafts. Oligonucleotide was delivered to grafts intraoperatively by ex-vivo pressure-mediated transfection. The primary endpoints were safety and inhibition of target cell-cycle regulatory genes and of DNA synthesis in the grafts. Analysis was by intention to treat.


RESULTS
Mean transfection efficiency was 89.0% (SD 1.9). Proliferating-cell nuclear antigen and c-myc mRNA concentrations and bromodeoxyuridine incorporation were decreased in the EF2-decoy group by medians of 73% [IQR 53-84], 70% [50-79], and 74% [56-83], respectively) but not in the scrambled-oligodeoxynucleotide group (p<0.0001). Groups did not differ for postoperative complication rates. At 12 months, fewer graft occlusions, revisions, or critical stenoses were seen in the E2F-decoy group than in the untreated group (hazard ratio 0.34 [95% CI 0.12-0.99]).


CONCLUSIONS
Intraoperative transfection of human bypass vein grafts with E2F-decoy oligodeoxynucleotide is safe, feasible, and can achieve sequence-specific inhibition of cell-cycle gene expression and DNA replication. Application of this genetic-engineering strategy may lower failure rates of human primary bypass vein grafting.
Mann
M J
MJ
Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
Whittemore
A D
AD
Donaldson
M C
MC
Belkin
M
M
Conte
M S
MS
Polak
J F
JF
Orav
E J
EJ
Ehsan
A
A
Dell'Acqua
G
G
Dzau
V J
VJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019917:Blood Vessel Prosthesis Implantation / Q000379:methods*; D001973:Bromodeoxyuridine / Q000378:metabolism; D002352:Carrier Proteins; D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors*; D004268:DNA-Binding Proteins; D004311:Double-Blind Method; D050684:E2F Transcription Factors; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D006083:Graft Occlusion, Vascular / Q000517:prevention & control*; D006085:Graft Survival; D006801:Humans; D015993:Life Tables; D008297:Male; D008875:Middle Aged; D009841:Oligonucleotides / Q000627:therapeutic use*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D056465:Retinoblastoma-Binding Protein 1; D018709:Statistics, Nonparametric; D050680:Transcription Factor DP1; D014157:Transcription Factors / Q000037:antagonists & inhibitors*; D014162:Transfection
D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D009841:Oligonucleotides; D018809:Proliferating Cell Nuclear Antigen; D016271:Proto-Oncogene Proteins c-myc; D056465:Retinoblastoma-Binding Protein 1; D050680:Transcription Factor DP1; D014157:Transcription Factors; D001973:Bromodeoxyuridine