title: Dual antitumoral potency of EG5 siRNA nanoplexes armed with cytotoxic bifunctional glutamyl-methotrexate targeting ligand.
abstract: Synthetic small interfering RNA (siRNA) is a class of therapeutic entities that allow for specific silencing of target genes via RNA interference (RNAi) and comprise an enormous clinical potential for a variety of diseases, including cancer. However, efficient tissue-specific delivery of siRNA remains the major limitation in the development of RNAi-based cancer therapeutics. To achieve this, we have synthesized a series of sequence-defined oligomers, which include a cationic (oligoethanamino)amide core (for nanoparticle formation with siRNA), cysteines (as bioreversible disulfide units), and a polyethylene glycol chain (for shielding of surface charges) coupled to a terminal targeting ligand. The antifolate drug methotrexate (MTX), a well-established chemotherapeutic agent, serves as both targeting ligand and anticancer agent. The oligomers form homogeneous spherical siRNA polyplexes with a hydrodynamic diameter of approximately 6 nm. These polyplexes access KB cells by binding to the folate receptor in a MTX-dependent manner and induce efficient gene silencing activity in vitro. Impressively, in the in vivo studies, MTX-conjugated polyplexes significantly increase the intratumoral retention (168 h) of the siRNA, as compared to alanine-substituted non-targeted control polyplexes (48 h). The combination of MTX-conjugated polyplexes and eglin 5 (EG5) siRNA provides enhanced antitumoral potency with 50% of recurrence-free survival of KB tumor-bearing mice. The design of such siRNA carrier systems with a dual-functional ligand for cellular delivery and augmented tumor suppression could be a valuable strategy for translating RNAi-based cancer therapeutics to the clinics.
authors.affiliation: Department of Pharmacy and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany; Nanosystems Initiative Munich, Germany.
authors.forename: Dian-Jang
authors.initials: DJ
authors.lastname: Lee
authors.affiliation: Department of Pharmacy and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany; Nanosystems Initiative Munich, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Kessel
authors.affiliation: Department of Pharmacy and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Edinger
authors.affiliation: Department of Pharmacy and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany; Nanosystems Initiative Munich, Germany.
authors.forename: Dongsheng
authors.initials: D
authors.lastname: He
authors.affiliation: Department of Pharmacy and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany.
authors.forename: Philipp M
authors.initials: PM
authors.lastname: Klein
authors.affiliation: Department of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany.
authors.forename: Lena
authors.initials: L
authors.lastname: Voith von Voithenberg
authors.affiliation: Department of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany; Nanosystems Initiative Munich, Germany.
authors.forename: Don C
authors.initials: DC
authors.lastname: Lamb
authors.affiliation: Department of Pharmacy and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany; Nanosystems Initiative Munich, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Lächelt
authors.affiliation: Department of Pharmacy and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany.
authors.forename: Taavi
authors.initials: T
authors.lastname: Lehto
authors.affiliation: Department of Pharmacy and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany; Nanosystems Initiative Munich, Germany. Electronic address: ernst.wagner@cup.uni-muenchen.de.
authors.forename: Ernst
authors.initials: E
authors.lastname: Wagner
mesh_terms: D000818:Animals; D002277:Carcinoma / Q000473:pathology; D002412:Cations; D045744:Cell Line, Tumor; D015536:Down-Regulation; D004337:Drug Carriers; D016503:Drug Delivery Systems; D005260:Female; D058973:Folate Receptors, GPI-Anchored / Q000378:metabolism; D017930:Genes, Reporter; D015316:Genetic Therapy; D006801:Humans; D007624:KB Cells; D016547:Kinesins / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D008727:Methotrexate / Q000008:administration & dosage* / Q000493:pharmacokinetics; D051379:Mice; D008819:Mice, Nude; D053769:Nanocapsules / Q000008:administration & dosage / Q000627:therapeutic use*; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics; D010455:Peptides / Q000008:administration & dosage* / Q000493:pharmacokinetics; D011092:Polyethylene Glycols / Q000008:administration & dosage; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000235:genetics / Q000627:therapeutic use*; D011897:Random Allocation; D014018:Tissue Distribution; D014162:Transfection; D002583:Uterine Cervical Neoplasms / Q000473:pathology; D023041:Xenograft Model Antitumor Assays
chemical_list: D002412:Cations; D004337:Drug Carriers; D058973:Folate Receptors, GPI-Anchored; C470243:KIF11 protein, human; D053769:Nanocapsules; D009363:Neoplasm Proteins; D010455:Peptides; D034741:RNA, Small Interfering; C097188:polyglutamine; D011092:Polyethylene Glycols; D016547:Kinesins; D008727:Methotrexate
keywords: Drug delivery; Methotrexate; Polyplexes; Tumor targeting; siRNA