title: Quantitative measurement of delivery and gene silencing activities of siRNA polyplexes containing pyridylthiourea-grafted polyethylenimines.
abstract: The activity of synthetic interfering nucleic acids (siRNAs) relies on the capacity of delivery systems to efficiently transport nucleic acids into the cytosol of target cells. The pyridylthiourea-grafted 25KDa polyethylenimine (πPEI) is an excellent carrier for siRNA delivery into cells and it was extensively investigated in this report. Quantification of the siRNA-mediated gene silencing efficiency indicated that the πPEI specific delivery activity at the cell level may be measured and appears relatively constant in various cell lines. Delivery experiments assaying inhibitors of various entry pathways or concanamycin A, an inhibitor of the H(+)/ATPase vacuolar pump showed that the πPEI/siRNA polyplexes did not require any specific entry mode but strongly relied on vacuolar acidification for functional siRNA delivery. Next, πPEI polyplexes containing a siRNA targeting the transcription factor HIF-1α, known to be involved in tumor progression, were locally injected into mice xenografted with a human glioblastoma. A 55% reduction of the level of the target mRNA was observed at doses comparable to those used in vitro when the πPEI delivery activity was calculated per cell. Altogether, our study underscores the usefulness of "simple"/rough cationic polymers for siRNA delivery despite their intrinsic limitations. The study underscores as well as that bottom-up strategies make sense. The in vitro experiments can precede in vivo administration and be of high value for selection of the carrier with enhanced specific delivery activity and parallel other research aiming at improving synthetic delivery systems for resilience in the blood and for enhanced tissue-targeting capacity.
authors.affiliation: Université de Lorraine, CNRS, CRAN, UMR 7039, Campus Sciences, 54500 Vandoeuvre les Nancy, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Pinel
authors.affiliation: Laboratoire de Conception et Application de Molécules Bioactives, CNRS - Université de Strasbourg UMR 7199, Faculté de Pharmacie, 74, Route du Rhin, F-67400 Illkirch, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Aman
authors.affiliation: Laboratoire de Conception et Application de Molécules Bioactives, CNRS - Université de Strasbourg UMR 7199, Faculté de Pharmacie, 74, Route du Rhin, F-67400 Illkirch, France.
authors.forename: Felix
authors.initials: F
authors.lastname: Erblang
authors.affiliation: Laboratoire de Conception et Application de Molécules Bioactives, CNRS - Université de Strasbourg UMR 7199, Faculté de Pharmacie, 74, Route du Rhin, F-67400 Illkirch, France.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Dietrich
authors.affiliation: Laboratoire de Conception et Application de Molécules Bioactives, CNRS - Université de Strasbourg UMR 7199, Faculté de Pharmacie, 74, Route du Rhin, F-67400 Illkirch, France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Frisch
authors.affiliation: Laboratoire de Conception et Application de Molécules Bioactives, CNRS - Université de Strasbourg UMR 7199, Faculté de Pharmacie, 74, Route du Rhin, F-67400 Illkirch, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Sirman
authors.affiliation: Laboratoire de Conception et Application de Molécules Bioactives, CNRS - Université de Strasbourg UMR 7199, Faculté de Pharmacie, 74, Route du Rhin, F-67400 Illkirch, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Kichler
authors.affiliation: Ecole Supérieure de Biotechnologie de Strasbourg, CNRS - Université de Strasbourg UMR, Bld Sébastien Brant, F-67412 Illkirch, France.
authors.forename: Annie-Paule
authors.initials: AP
authors.lastname: Sibler
authors.affiliation: Laboratoire de Biophotonique et Pharmacologie, CNRS - Université de Strasbourg UMR 7213, Faculté de Pharmacie, 74, Route du Rhin, F-67400 Illkirch, France.
authors.forename: Monique
authors.initials: M
authors.lastname: Dontenwill
authors.affiliation: Laboratoire de Biophotonique et Pharmacologie, CNRS - Université de Strasbourg UMR 7213, Faculté de Pharmacie, 74, Route du Rhin, F-67400 Illkirch, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Schaffner
authors.affiliation: Laboratoire de Conception et Application de Molécules Bioactives, CNRS - Université de Strasbourg UMR 7199, Faculté de Pharmacie, 74, Route du Rhin, F-67400 Illkirch, France.. Electronic address: zuber@unistra.fr.
authors.forename: Guy
authors.initials: G
authors.lastname: Zuber
mesh_terms: D000818:Animals; D002460:Cell Line; D045744:Cell Line, Tumor; D006224:Cricetinae; D005260:Female; D020868:Gene Silencing; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics; D051379:Mice; D009369:Neoplasms / Q000235:genetics / Q000628:therapy; D011094:Polyethyleneimine / Q000008:administration & dosage* / Q000737:chemistry; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000737:chemistry; D013890:Thiourea / Q000008:administration & dosage* / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D011094:Polyethyleneimine; D013890:Thiourea
keywords: Glioblastoma; In vivo; Polyethylenimine; Polyplexes; siRNA delivery