Smooth Muscle Cell-targeted RNA Aptamer Inhibits Neointimal Formation

Mol Ther. 2016 Apr;24(4):779-87. doi: 10.1038/mt.2015.235. Epub 2016 Jan 6.

Abstract

Inhibition of vascular smooth muscle cell (VSMC) proliferation by drug eluting stents has markedly reduced intimal hyperplasia and subsequent in-stent restenosis. However, the effects of antiproliferative drugs on endothelial cells (EC) contribute to delayed re-endothelialization and late stent thrombosis. Cell-targeted therapies to inhibit VSMC remodeling while maintaining EC health are necessary to allow vascular healing while preventing restenosis. We describe an RNA aptamer (Apt 14) that functions as a smart drug by preferentially targeting VSMCs as compared to ECs and other myocytes. Furthermore, Apt 14 inhibits phosphatidylinositol 3-kinase/protein kinase-B (PI3K/Akt) and VSMC migration in response to multiple agonists by a mechanism that involves inhibition of platelet-derived growth factor receptor (PDGFR)-β phosphorylation. In a murine model of carotid injury, treatment of vessels with Apt 14 reduces neointimal formation to levels similar to those observed with paclitaxel. Importantly, we confirm that Apt 14 cross-reacts with rodent and human VSMCs, exhibits a half-life of ~300 hours in human serum, and does not elicit immune activation of human peripheral blood mononuclear cells. We describe a VSMC-targeted RNA aptamer that blocks cell migration and inhibits intimal formation. These findings provide the foundation for the translation of cell-targeted RNA therapeutics to vascular disease.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aptamers, Nucleotide / pharmacology*
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • Cells, Cultured
  • Gene Expression Regulation / drug effects
  • Half-Life
  • Humans
  • Mice
  • Muscle, Smooth, Vascular / cytology*
  • Muscle, Smooth, Vascular / drug effects
  • Myocytes, Smooth Muscle / cytology
  • Myocytes, Smooth Muscle / drug effects*
  • Neointima / metabolism
  • Neointima / therapy*
  • Phosphatidylinositol 3-Kinases / metabolism*
  • Phosphorylation
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Rats

Substances

  • Aptamers, Nucleotide
  • Phosphatidylinositol 3-Kinases
  • Proto-Oncogene Proteins c-akt