1-2-dielaidoylphosphatidylethanolamine and Colonic-Neoplasms

The cationic lipid mediated uptake of plasmid DNA by cells in monolayer culture was significantly enhanced with an aqueous solution of the block copolymer poly(p-dioxanone-co-L-lactide)-b-poly(ethylene glycol) (PPDO/PLLA-b-PEG). Plasmid uptake studies with DNA encoding the beta-galactosidase gene and cytotoxicity evaluations were performed on MCF-7, NIH 3T3 and CT-26 cell lines. Transfection yields and time courses for maximum release of FITC labeled DNA in MCF-7 cells were observed and quantified by beta-galactosidase assay and spectrofluorometry, respectively. The reported results suggest that the studied block copolymer might be useful for the enhancement of polycation mediated transfection and could find application in gene therapy.

Topics: 3T3 Cells; Animals; Biological Transport; Breast Neoplasms; Cell Line, Tumor; Colonic Neoplasms; DNA; Humans; Kinetics; Materials Testing; Mice; Phosphatidylethanolamines; Plasmids; Polyesters; Polyethylene Glycols; Transfection

A natural DNA oligomer (15-mer) was synthesized with a sequence complementary to the translation initiation codon region of the human TGF-alpha mRNA and mixed with Lipofectin to form unilamellar complexes. It was found that tumor cell growth was inhibited when HCT116 cells were treated with Lipofectin-DNA oligomer complexes or with Lipofectin alone. Uptake of 32P-labeled 15-mers into colon tumor cells was compared in the presence and absence of Lipofectin. The amount of labeled oligomer found in cells that received optimal ratios of Lipofectin to DNA was 4- to 10-fold higher than the amount found in cells that received 32P-labeled DNA alone. Although Lipofectin-antisense DNA oligomer treatment of HCT116 cells caused a dose-dependent inhibition of cell growth, there was a subsequent rise in target mRNA product. Because the mechanism of growth inhibition could not involve an inhibition of TGF-alpha expression, it was concluded that Lipofectin probably exerts a nonspecific, detergent-like effect upon the cell membrane, producing an enhancement of TGF-alpha processing and release.

Topics: Base Sequence; Biological Transport; Cell Division; Cell Line; Chloramphenicol O-Acetyltransferase; Colonic Neoplasms; DNA, Antisense; Epidermal Growth Factor; Humans; Insulin; Kinetics; Molecular Sequence Data; Oligonucleotides, Antisense; Phosphatidylethanolamines; Promoter Regions, Genetic; Transfection; Transforming Growth Factor alpha; Tumor Cells, Cultured