title: Solid-phase synthesis, characterization and RNAi activity of branch and hyperbranch siRNAs.
abstract: Linear, branch and hyperbranch siRNAs were effectively prepared for down-regulating GRP78 expression and inducing cell death in HepG2 liver cancer cells. Branch and hyperbranch GRP78 siRNAs were synthesized by automated solid-phase synthesis in good yields (44-78%) and isolated in excellent purities (>99%) following HPLC purification. Moreover, siRNAs adopted stable intramolecular hybrids as discerned by native PAGE and thermal denaturation studies. These sequences also exhibited the pre-requisite A-type helical trajectory for triggering RNAi activity as determined by CD spectroscopy. Biological studies confirmed potent suppression of GRP78 expression (50-60%) while compromising cancer cell viability by ~20%. Thus, branch and hyperbranch siRNAs may serve as potent siRNA candidates in cancer gene therapy applications.
authors.affiliation: Department of Chemistry and Biochemistry, Seton Hall University, South Orange, NJ 07079, USA.
authors.forename: Anthony
authors.initials: A
authors.lastname: Maina
authors.forename: Brittany A
authors.initials: BA
authors.lastname: Blackman
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Parronchi
authors.forename: Eva
authors.initials: E
authors.lastname: Morozko
authors.forename: Maria E
authors.initials: ME
authors.lastname: Bender
authors.forename: Allan D
authors.initials: AD
authors.lastname: Blake
authors.forename: David
authors.initials: D
authors.lastname: Sabatino
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D000091342:Endoplasmic Reticulum Chaperone BiP; D056945:Hep G2 Cells; D006801:Humans; D018613:Microscopy, Confocal; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000138:chemical synthesis* / Q000235:genetics / Q000494:pharmacology; D060327:Solid-Phase Synthesis Techniques
chemical_list: D000970:Antineoplastic Agents; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D034741:RNA, Small Interfering
keywords: Branch siRNA; GRP78 silencing; Hyperbranch siRNA; Oncogene therapy; RNAi