Related Experiment Video
Updated: Jun 5, 2026
In Vivo Nanovector Delivery of a Heart-specific MicroRNA-sponge
Published on: June 15, 2018
In vitro characterization of two novel biodegradable vectors for the delivery of radiolabeled antisense
Elisabeth von Guggenberg1, Soraya Shahhosseini, Ingrid Koslowsky
1Department of Nuclear Medicine, Innsbruck Medical University, Austria.
Abstract:
The development of antisense oligonucleotides suitable for tumor targeting applications is hindered by low stability and bioavailability of oligonucleotides in vivo and by the absence of efficient and safe vectors for oligonucleotide delivery. Stabilization in vivo has been achieved through chemical modification of oligonucleotides by various means, but effective approaches to enhance their intracellular delivery are lacking. This study reports on the characterization in vitro of a fully phosphorothioated 20-mer oligonucleotide, complementary to p21 mRNA, radiolabeled with fluorine-18 using a thiol reactive prosthetic group. The potential of two novel synthetic block copolymers containing grafted polyamines on their hydrophobic blocks for vector-assisted cell delivery was studied in vitro. Extensive cellular uptake studies were performed in human colon carcinoma cell lines with enhanced or deficient p21 expression to evaluate and compare the uptake mechanism of naked and vectorized radiolabeled formulations. Uptake studies with the two novel biodegradable vectors showed a moderate increase in cell uptake of the radiofluorinated antisense oligonucleotide. The two vectors show, however, promising advantages over conventional lipidic vectors regarding their biocompatibility and subcellular distribution.
Insights
Researchers developed novel biodegradable vectors to improve the delivery of antisense oligonucleotides for cancer therapy. These vectors showed enhanced cellular uptake and better biocompatibility compared to traditional lipid-based methods.
Area of Science:
- Biotechnology
- Molecular Biology
- Oncology
Background:
- Antisense oligonucleotides (ASOs) show promise for tumor targeting but face challenges in stability, bioavailability, and efficient intracellular delivery.
- Current methods for in vivo stabilization of ASOs exist, yet effective strategies for enhancing their delivery into cells are limited.
Purpose of the Study:
- To characterize a novel radiofluorinated antisense oligonucleotide targeting p21 mRNA in vitro.
- To evaluate the efficacy of two new synthetic block copolymers with grafted polyamines as vectors for ASO delivery.
- To compare the cellular uptake and intracellular distribution of naked versus vectorized ASO formulations in human colon carcinoma cell lines.
Main Methods:
- A 20-mer phosphorothioated oligonucleotide complementary to p21 mRNA was synthesized and radiolabeled with fluorine-18.
- Two novel biodegradable block copolymers with grafted polyamines were developed as potential delivery vectors.
- In vitro cellular uptake studies were conducted using human colon carcinoma cell lines with varying p21 expression levels.
Main Results:
- The radiofluorinated antisense oligonucleotide was successfully characterized in vitro.
- The novel biodegradable vectors demonstrated a moderate increase in the cellular uptake of the antisense oligonucleotide.
- These vectors exhibited improved biocompatibility and subcellular distribution compared to conventional lipidic vectors.
Conclusions:
- Novel biodegradable polyamine-grafted block copolymers show potential as safe and effective vectors for delivering antisense oligonucleotides.
- These vectors offer advantages over traditional lipidic vectors for enhancing ASO delivery in cancer therapy applications.
- Further research is warranted to optimize these vectors for in vivo tumor targeting and therapeutic efficacy.
