Aptamer-based Targeted Delivery of a G-quadruplex Ligand in Cervical Cancer Cells

Sci Rep. 2019 May 28;9(1):7945. doi: 10.1038/s41598-019-44388-9.

Abstract

AS1411 is a G-rich DNA oligonucleotide that functions as an aptamer of the protein nucleolin, found at high levels on the surface of cancer cells but not on the surface of normal cells. Herein, we have studied AS1411 as a supramolecular carrier for the delivery of an acridine-based G-quadruplex ligand, C8, to HeLa cancer cells. Two AS1411 derivatives, LNA-AS1411 and U-AS1411, were also tested, in an attempt to compare AS1411 pharmacological properties. The results showed that AS1411-C8 complexation was made with great binding strength and that it lowered the ligand's cytotoxicity towards non-malignant cells. This effect was suggested to be due to a decreased internalization of the complexed versus free C8 as shown by flow cytometry. The AS1411 derivatives, despite forming a stable complex with C8, lacked the necessary tumour-selective behaviour. The binding of C8 to AS1411 G-quadruplex structure did not negatively affect the recognition of nucleolin by the aptamer. The AS1411-C8 repressed c-MYC expression at the transcriptional level, possibly due to C8 ability to stabilize the c-MYC promoter G-quadruplexes. Overall, this study demonstrates the usefulness of AS1411 as a supramolecular carrier of the G-quadruplex binder C8 and the potential of using its tumour-selective properties for the delivery of ligands for cancer therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • A549 Cells
  • Antineoplastic Agents / metabolism
  • Antineoplastic Agents / pharmacology*
  • Aptamers, Nucleotide / metabolism
  • Aptamers, Nucleotide / pharmacology*
  • Cell Line
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Fibroblasts / cytology
  • Fibroblasts / drug effects
  • Fibroblasts / metabolism
  • G-Quadruplexes*
  • Gene Expression Regulation, Neoplastic*
  • Gene Transfer Techniques
  • HeLa Cells
  • Humans
  • Ligands
  • Nucleolin
  • Oligodeoxyribonucleotides / metabolism
  • Oligodeoxyribonucleotides / pharmacology*
  • Organ Specificity
  • Phosphoproteins / antagonists & inhibitors
  • Phosphoproteins / genetics*
  • Phosphoproteins / metabolism
  • Promoter Regions, Genetic
  • Protein Binding
  • Proto-Oncogene Proteins c-myc / genetics*
  • Proto-Oncogene Proteins c-myc / metabolism
  • RNA-Binding Proteins / antagonists & inhibitors
  • RNA-Binding Proteins / genetics*
  • RNA-Binding Proteins / metabolism
  • Transcription, Genetic

Substances

  • AGRO 100
  • Antineoplastic Agents
  • Aptamers, Nucleotide
  • Ligands
  • Oligodeoxyribonucleotides
  • Phosphoproteins
  • Proto-Oncogene Proteins c-myc
  • RNA-Binding Proteins