title: In Silico, In Vitro, and In Vivo Studies Indicate the Potential Use of Bolaamphiphiles for Therapeutic siRNAs Delivery.
abstract: Specific small interfering RNAs (siRNAs) designed to silence different oncogenic pathways can be used for cancer therapy. However, non-modified naked siRNAs have short half-lives in blood serum and encounter difficulties in crossing biological membranes due to their negative charge. These obstacles can be overcome by using siRNAs complexed with bolaamphiphiles, consisting of two positively charged head groups that flank an internal hydrophobic chain. Bolaamphiphiles have relatively low toxicities, long persistence in the blood stream, and most importantly, in aqueous conditions can form poly-cationic micelles thus, becoming amenable to association with siRNAs. Herein, two different bolaamphiphiles with acetylcholine head groups attached to an alkyl chain in two distinct configurations are compared for their abilities to complex with siRNAs and deliver them into cells inducing gene silencing. Our explicit solvent molecular dynamics (MD) simulations showed that bolaamphiphiles associate with siRNAs due to electrostatic, hydrogen bonding, and hydrophobic interactions. These in silico studies are supported by various in vitro and in cell culture experimental techniques as well as by some in vivo studies. Results demonstrate that depending on the application, the extent of siRNA chemical protection, delivery efficiency, and further intracellular release can be varied by simply changing the type of bolaamphiphile used.Molecular Therapy-Nucleic Acids (2013) 2, e80; doi:10.1038/mtna.2013.5; published online 19 March 2013.
authors.affiliation: Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, Maryland, USA.
authors.forename: Taejin
authors.initials: T
authors.lastname: Kim
authors.forename: Kirill A
authors.initials: KA
authors.lastname: Afonin
authors.forename: Mathias
authors.initials: M
authors.lastname: Viard
authors.forename: Alexey Y
authors.initials: AY
authors.lastname: Koyfman
authors.forename: Selene
authors.initials: S
authors.lastname: Sparks
authors.forename: Eliahu
authors.initials: E
authors.lastname: Heldman
authors.forename: Sarina
authors.initials: S
authors.lastname: Grinberg
authors.forename: Charles
authors.initials: C
authors.lastname: Linder
authors.forename: Robert P
authors.initials: RP
authors.lastname: Blumenthal
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Shapiro