In vitro and in vivo evaluation of recombinant silk-elastinlike hydrogels for cancer gene therapy.
The objectives of this study were to evaluate: (i). the influences of hydrogel geometry, DNA molecular weight, and DNA conformation on DNA release from a silk-elastinlike protein polymer (SELP) hydrogel, (ii). the bioactivity and transfection efficiency of encapsulated DNA over time in vitro, (iii). the delivery and transfection of a reporter gene in a murine model of human breast cancer in vivo, and (iv). the in vitro release and bioactivity of adenovirus containing the green fluorescent protein (gfp) gene as a marker of gene transfer. Plasmid DNA was released from SELP hydrogels in a size-dependent manner, with the average effective diffusivity ranging from 1.70+/-0.52 x 10(-12) cm(2)/s for a larger plasmid (11 kbp) to 2.55+/-0.51 x 10(-10) cm(2)/s for a smaller plasmid (2.6 kbp). Plasmid conformation also influenced the rate of release, with the rank order linear>supercoiled>open-circular. DNA retained bioactivity in vitro, after encapsulation in a SELP hydrogel for up to 28 days. Delivery of pRL-CMV from a SELP hydrogel resulted in increased transfection in a murine model of human breast cancer by 1-3 orders of magnitude, as compared to naked DNA. The release of a bioactive adenoviral vector was related to the concentration of the polymer in the hydrogel. These studies indicate that genetically engineered SELP hydrogels have potential as matrices for controlled nonviral and viral gene delivery.
Megeed
Zaki
Z
Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 North Penn Street, Baltimore, MD 21201, USA.
Haider
Mohamed
M
Li
Daqing
D
O'Malley
Bert W
BW
Cappello
Joseph
J
Ghandehari
Hamidreza
H
D000595:Amino Acid Sequence; D000818:Animals; D004353:Drug Evaluation, Preclinical / Q000379:methods; D004549:Elastin / Q000008:administration & dosage* / Q000493:pharmacokinetics; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D020100:Hydrogels / Q000008:administration & dosage* / Q000493:pharmacokinetics; D019476:Insect Proteins / Q000008:administration & dosage* / Q000493:pharmacokinetics; D051379:Mice; D008819:Mice, Nude; D008969:Molecular Sequence Data; D009369:Neoplasms / Q000188:drug therapy* / Q000235:genetics; D010957:Plasmids / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000627:therapeutic use; D047011:Silk; D023041:Xenograft Model Antitumor Assays / Q000379:methods
D020100:Hydrogels; D019476:Insect Proteins; D011994:Recombinant Proteins; D047011:Silk; D004549:Elastin