Potential c-myc antisense oligonucleotide carriers: PCl/PEG/PEI and PLL/PEG/PEI

Thermo-Responsive Complexes of c-Myc Antisense Oligonucleotide with Block Copolymer of Poly(OEGMA) and Quaternized Poly(4-Vinylpyridine)

Solution behavior of thermo-responsive polymers and their complexes with biological macromolecules may be affected by environmental conditions, such as the concentration of macromolecular components, pH, ion concentration, etc. Therefore, a thermo-responsive polymer and its complexes should be characterized in detail to observe their responses against possible environments under physiological conditions before biological applications. To briefly indicate this important issue, thermo-responsive block copolymer of quaternized poly(4-vinylpyridine) and poly(oligoethyleneglycol methyl ether methacrylate) as a potential nonviral vector has been synthesized. Polyelectrolyte complexes of this copolymer with the antisense oligonucleotide of c-Myc oncogene are also thermo-responsive but, have lower LCST (lower critical solution temperature) values compared to individual copolymer. LCST values of complexes decrease with molar ratio of macromolecular components and presence of salt. Dilution of solutions also affects solution behavior of complexes and causes a significant decrease in size and an increase in LCST, which indicates possible effects of severe dilutions in the blood stream.

Antisense oligonucleotide delivery to cancer cell lines for the treatment of different cancer types

Amphiphilic poly(3-hydroxylalkanoate) (PHA) copolymers find interesting applications in drug delivery. The aim of this study was to prepare nucleic acid adsorbed on (PHB-b-PEG-NH₂) nanoparticle platform for gene delivery. For this purpose, PHB-b-PEG-NH₂ block copolymers were synthesized via transesterification reactions. The copolymers obtained were characterized by Proton Nuclear Magnetic Resonance (¹H-NMR), Fourier Transform Infrared Spectrometer (FTIR), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) techniques. The cytotoxic, apoptotic and necrotic effects of these nanoparticles in the MDA 231 human breast cancer cell, the A549 human lung cancer cell and the L929 fibroblast cell lines were also investigated.