Conjugation with receptor-targeted histidine-rich peptides enhances the pharmacological effectiveness of antisense oligonucleotides

Bioconjug Chem. 2014 Jan 15;25(1):165-70. doi: 10.1021/bc400500h. Epub 2013 Dec 19.

Abstract

Ineffective delivery to intracellular sites of action is one of the key limitations to the use of antisense and siRNA oligonucleotides as therapeutic agents. Here, we describe molecular scale antisense oligonucleotide conjugates that bind selectively to a cell surface receptor, are internalized, and then partially escape from nonproductive endosomal locations to reach their sites of action in the nucleus. Peptides that include bombesin sequences for receptor targeting and a run of histidine residues for endosomal disruption were covalently linked to a splice switching antisense oligonucleotide. The conjugates were tested for their ability to correct splicing and up-regulate expression of a luciferase reporter in prostate cancer cells that express the bombesin receptor. We found that trivalent conjugates that included both the targeting sequence and several histidine residues were substantially more effective than conjugates containing only the bombesin or histidine moieties. This demonstrates the potential of creating molecular scale oligonucleotide conjugates with both targeting and endosome escape capabilities.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Cell Line, Tumor
  • Dose-Response Relationship, Drug
  • Humans
  • Molecular Structure
  • Oligonucleotides, Antisense / chemistry
  • Oligonucleotides, Antisense / pharmacology*
  • Proteins / chemistry*
  • Proteins / metabolism
  • Receptors, Bombesin / antagonists & inhibitors*
  • Receptors, Bombesin / biosynthesis
  • Receptors, Bombesin / chemistry
  • Structure-Activity Relationship

Substances

  • Oligonucleotides, Antisense
  • Proteins
  • Receptors, Bombesin
  • histidine-rich proteins