title: Cyclodextrin-containing polymer delivery system for light-directed siRNA gene silencing.
abstract: In this study, we have investigated the possibility of combining a cyclodextrin-containing polymer (CDP) with siRNA molecules to modulate gene expression in a light-directed manner through photochemical internalization (PCI) technology. We utilized S100A4 as a model gene to evaluate the efficacy of gene silencing. After optimization of carrier/cargo ratio and illumination dose, real-time reverse transcriptase-polymerase chain reaction data showed between 80% and 90% silencing in the siRNA samples treated with PCI compared with untreated control. In contrast, only a 0%-10% silencing effect was detected in the siRNA samples without PCI treatment, demonstrating the potency of light-specific delivery of siRNA molecules. Light-directed siRNA delivery was shown in 2 different cell lines with corresponding potency. Further, time-lapse results demonstrated maximum gene silencing only at 5 hours after endosomal release, implying, for example, rapid carrier decondensation when using the CDP. This work represents a first success in using a CDP delivery agent, without endosomolytic properties for siRNA gene silencing in a light-directed manner, opening the opportunity to use CDPs for light-directed siRNA gene silencing in vivo.
authors.affiliation: Department of Tumor Biology, Institute of Cancer Research, The Norwegian Radium Hospital, Montebello, Oslo, Norway. sigurdbo@rr-research.no
authors.forename: Sigurd Leinaes
authors.initials: SL
authors.lastname: Bøe
authors.forename: Ane Sager
authors.initials: AS
authors.lastname: Longva
authors.forename: Eivind
authors.initials: E
authors.lastname: Hovig
mesh_terms: D001483:Base Sequence; D045744:Cell Line, Tumor; D002470:Cell Survival; D002482:Cellulose / Q000737:chemistry; D003505:Cyclodextrins / Q000737:chemistry; D017931:DNA Primers / Q000235:genetics; D016503:Drug Delivery Systems; D011992:Endosomes / Q000378:metabolism; D020868:Gene Silencing; D006801:Humans; D008027:Light; D008247:Lysosomes / Q000378:metabolism; D055668:Photochemical Processes; D011108:Polymers / Q000737:chemistry; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000235:genetics*; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins / Q000037:antagonists & inhibitors / Q000235:genetics; D014162:Transfection
chemical_list: D003505:Cyclodextrins; D017931:DNA Primers; D011108:Polymers; D034741:RNA, Small Interfering; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins; C041953:cyclodextrin polymer; C077591:S100A4 protein, human; D002482:Cellulose