Rad51 promoter-targeted gene therapy is effective for in vivo visualization and treatment of cancer.

Abstract

Rad51 protein is overexpressed in a wide range of human cancers. Our previous in vitro studies demonstrated that a construct comprised Rad51 promoter driving expression of the diphtheria toxin A gene (pRad51-diphtheria toxin A (DTA)) destroys a variety of human cancer cell lines, with minimal to no toxicity to normal human cells. Here we delivered Rad51 promoter-based constructs in vivo using linear polyethylenimine nanoparticles, in vivo jetPEI, to visualize and treat tumors in mice with HeLa xenografts. For tumor detection, we used pRad51-Luc, a construct containing the firefly luciferase under the Rad51 promoter, administered by intraperitoneal (IP) injection. Tumors were detected with an in vivo bioluminescent camera. All mice with cancer displayed strong bioluminescence, while mice without cancer displayed no detectable bioluminescence. Treatment with pRad51-DTA/jetPEI decreased tumor mass of subcutaneous (SC) and IP tumors by sixfold and fourfold, respectively, along with the strong reduction of malignant ascites. Fifty percent of the mice with SC tumors were cancer-free after six pRad51-DTA/jetPEI injections, and for the mice with IP tumors, mean survival time increased by 90% compared to control mice. This study demonstrates the clinical potential of pRad51-based constructs delivered by nanoparticles for the diagnostics and treatment of a wide range of cancers.

• Authors: Christopher M Hine, Andrei Seluanov, Vera Gorbunova
• Journal: Molecular therapy : the journal of the American Society of Gene Therapy (Mol Ther) Vol. 20 Issue 2 Pg. 347-55 (Feb 2012) ISSN: 1525-0024 [Electronic] United States
• PMID: 22008909 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• Diphtheria Toxin
• Luminescent Proteins
• Nanoconjugates
• Polyethyleneimine
• Rad51 Recombinase

Topics

• Animals
• Cell Line, Tumor
• Diphtheria Toxin (chemistry, genetics)
• Gene Order
• Gene Transfer Techniques
• Genetic Therapy
• Humans
• Luminescent Proteins (genetics, metabolism)
• Mice
• Molecular Imaging
• Nanoconjugates (administration & dosage, adverse effects, chemistry)
• Neoplasms (genetics, mortality, therapy)
• Plasmids (chemistry, genetics)
• Polyethyleneimine (chemistry)
• Promoter Regions, Genetic
• Rad51 Recombinase (genetics)
• Survival Analysis
• Tumor Burden
• Xenograft Model Antitumor Assays