title: Cellular delivery of shRNA using aptamer-conjugated PLL-alkyl-PEI nanoparticles.
abstract: Introduction of an efficient gene delivery vector is still the main challenge of gene therapy. Both polyethylenimine (PEI) and poly(l-lysine) (PLL) comprise disadvantages which limited their application. To explore whether their deficiencies could be compensated by preparing copolymers consisting of both PLL and PEI, we generated several combinations of PLL-alkyl-PEI copolymers conjugated to aptamer and evaluated their both gene delivery efficiency and down-regulation of Bcl-XL, an anti-apoptotic gene, in lung cancer cell line. PLL was conjugated to either 10% or 50% of PEI by grafting different percentages of PEI to alkylated-PLL as core. The properties of modified polymers including size, surface charge density, DNA condensation ability, buffering capacity and cytotoxicity were evaluated. According to transfection results, aptamer conjugated PLL-alkyl-10%-PEI (PLPE8%) was selected for further gene silencing study by plasmid shRNA. Decrease in Bcl-XL gene expression was estimated by both RT-PCR and western-blot experiments. The obtained results revealed that the new copolymers had appropriate nano-scale size (117-128 nm) even after aptamer conjugation (168-183 nm). Moreover, they exhibited increased transfection efficiencies by up to 1.8-5 folds and acceptable cytotoxicity. The apoptosis was induced in transfected cells by shRNA-aptamer-copolymer due to the down-regulation of mRNA and protein levels. This study suggested a new vector for targeted non-viral gene delivery with high transfection efficiency in lung cancer or pulmonary systems.
authors.affiliation: Department of Medical Biotechnology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: askarians891@mums.ac.ir.
authors.forename: Saeedeh
authors.initials: S
authors.lastname: Askarian
authors.affiliation: Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: abnouskh@mums.ac.ir.
authors.forename: Khalil
authors.initials: K
authors.lastname: Abnous
authors.affiliation: Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: taghaviS881@mums.ac.ir.
authors.forename: Sahar
authors.initials: S
authors.lastname: Taghavi
authors.affiliation: Department of Medical Biotechnology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: oskueekr@mums.ac.ir.
authors.forename: Reza Kazemi
authors.initials: RK
authors.lastname: Oskuee
authors.affiliation: Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran; Nanotechnology Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: ramezanim@mums.ac.ir.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ramezani
mesh_terms: D017209:Apoptosis; D052157:Aptamers, Nucleotide / Q000008:administration & dosage*; D045744:Cell Line, Tumor; D006801:Humans; D018625:Microscopy, Atomic Force; D053758:Nanoparticles; D011094:Polyethyleneimine / Q000737:chemistry*; D011107:Polylysine / Q000737:chemistry*; D034741:RNA, Small Interfering / Q000008:administration & dosage*
chemical_list: D052157:Aptamers, Nucleotide; D034741:RNA, Small Interfering; D011107:Polylysine; D011094:Polyethyleneimine
keywords: Aptamer; Bcl-XL shRNA; Gene delivery; Non-viral vector; Poly(l-lysine); Polyethylenimine