title: Phosphonium Polymethacrylates for Short Interfering RNA Delivery: Effect of Polymer and RNA Structural Parameters on Polyplex Assembly and Gene Knockdown.
abstract: Synthetic polymers containing quaternary phosphonium salts are an emerging class of materials for the delivery of oligo/polynucleotides. In this work, cationic phosphonium salt-containing polymethacrylates and their corresponding ammonium analogues were synthesized by reversible addition-fragmentation chain transfer polymerization. Both the nature of the charged heteroatom (N vs P) and the length of the spacer separating the cationic units along the polymer backbone (oxyethylene vs trioxyethylene) were systematically varied. Polymers efficiently bound short interfering RNA (siRNA) at N(+)/P(-) or P(+)/P(-) ratios of 2 and above. At a 20:1 ratio, small polyplexes (Rh: 4-15 nm) suitable for cellular uptake were formed that displayed low cytotoxicity. While siRNA polyplexes from both ammonium and phosphonium polymers were efficiently internalized by green fluorescent protein (GFP)-expressing 3T3 cells, no knockdown of GFP expression was observed. However, 65% Survivin gene knockdown was observed when siRNA was replaced with novel, multimerized long interfering RNA in HeLa cells, demonstrating the importance of RNA macromolecular architecture on RNA-mediated gene silencing.
authors.affiliation: School of Pharmacy, University of Nottingham , Boots Science Building, University Park, Nottingham NG7 2RD, U.K.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Loczenski Rose
authors.affiliation: School of Pharmacy, University of Nottingham , Boots Science Building, University Park, Nottingham NG7 2RD, U.K.
authors.forename: Saif
authors.initials: S
authors.lastname: Shubber
authors.affiliation: Global Research Laboratory for RNAi Medicine, Department of Chemistry, Sungkyunkwan University , Suwon 440-746, Republic of Korea.
authors.forename: S
authors.initials: S
authors.lastname: Sajeesh
authors.affiliation: Department of Chemistry, University of Sheffield , Dainton Building, Sheffield S3 7HF, U.K.
authors.forename: Sebastian G
authors.initials: SG
authors.lastname: Spain
authors.affiliation: Pharmaceutical Development, Astrazeneca UK Ltd. , Alderley Park, Macclesfield SK10 2NA, U.K.
authors.forename: Sanyogitta
authors.initials: S
authors.lastname: Puri
authors.affiliation: School of Pharmacy, University of Nottingham , Boots Science Building, University Park, Nottingham NG7 2RD, U.K.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Allen
authors.affiliation: Global Research Laboratory for RNAi Medicine, Department of Chemistry, Sungkyunkwan University , Suwon 440-746, Republic of Korea.
authors.forename: Dong-Ki
authors.initials: DK
authors.lastname: Lee
authors.affiliation: School of Pharmacy, University of Nottingham , Boots Science Building, University Park, Nottingham NG7 2RD, U.K.
authors.forename: G Sebastiaan
authors.initials: GS
authors.lastname: Winkler
authors.affiliation: School of Pharmacy, University of Nottingham , Boots Science Building, University Park, Nottingham NG7 2RD, U.K.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Mantovani
mesh_terms: D016475:3T3 Cells; D000818:Animals; D002412:Cations / Q000737:chemistry; D002470:Cell Survival / Q000187:drug effects; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D020868:Gene Silencing; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D046911:Macromolecular Substances / Q000737:chemistry; D051379:Mice; D010316:Particle Size; D058105:Polymerization; D011109:Polymethacrylic Acids / Q000737:chemistry*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000737:chemistry / Q000235:genetics*
chemical_list: D002412:Cations; D046911:Macromolecular Substances; D011109:Polymethacrylic Acids; D034741:RNA, Small Interfering; D049452:Green Fluorescent Proteins; C030613:polymethacrylic acid