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Phosphorothioate-stimulated uptake of short interfering RNA by human cells.

ABSTRACT: The cellular delivery of short interfering RNA (siRNA) is a main hurdle in therapeutic drug development. Here, we describe that phosphorothioate (PTO)-derived oligonucleotides stimulate the physical cellular uptake of siRNA in trans in human cells. This is reflected by an apparent dose-dependent siRNA-mediated suppression of lamin A/C in primary human umbilical vein endothelial cells. The PTO-stimulated cellular uptake in trans is concentration dependent, length dependent, related to the phosphorothioate chemistry but not sequence specific. We provide experimental evidence to support a caveolin-mediated uptake mechanism. In sum, this work strongly suggests the exploration of PTOs as facilitators in the delivery of biologically active siRNA to mammalian cells.

SUBMITTER: Overhoff M

PROVIDER: S-EPMC1369202 | biostudies-literature | 2005 Dec

REPOSITORIES: biostudies-literature

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Phosphorothioate-stimulated uptake of short interfering RNA by human cells.

Overhoff Marita M Sczakiel Georg G

EMBO reports 20051201 12

The cellular delivery of short interfering RNA (siRNA) is a main hurdle in therapeutic drug development. Here, we describe that phosphorothioate (PTO)-derived oligonucleotides stimulate the physical cellular uptake of siRNA in trans in human cells. This is reflected by an apparent dose-dependent siRNA-mediated suppression of lamin A/C in primary human umbilical vein endothelial cells. The PTO-stimulated cellular uptake in trans is concentration dependent, length dependent, related to the phospho ...[more]

PMID: 16170302

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