Aptamer-Mediated Targeted Delivery of Therapeutics: An Update

Abstract

The selective delivery of drugs in a cell- or tissue-specific manner represents the main challenge for medical research; in order to reduce the occurrence of unwanted off-target effects. In this regard, nucleic acid aptamers have emerged as an attractive class of carrier molecules due to their ability to bind with high affinity to specific ligands; their high chemical flexibility; as well as tissue penetration capability. To date, different aptamer-drug systems and aptamer–nanoparticles systems, in which nanoparticles function together with aptamers for the targeted delivery, have been successfully developed for a wide range of therapeutics, including toxins; peptides; chemotherapeutics and oligonucleotides. Therefore, aptamer-mediated drug delivery represents a powerful tool for the safe and effective treatment of different human pathologies, including cancer; neurological diseases; immunological diseases and so on. In this review, we will summarize recent progress in the field of aptamer-mediated drug delivery and we will discuss the advantages, the achieved objectives and the challenges to be still addressed in the near future, in order to improve the effectiveness of therapies.

Aptamer Grafting onto (on) and into (in) Pegylated Gold Nanoparticles: Physicochemical Characterization and In vitro Cytotoxicity Investigation in Renal Cells

“…Some bands are specific to the APT as the peak at 1058 cm -1 typical of phosphate group (PO 4 3-) [46] or the intense peak at 1371 cm -1 which corresponds to thymine base. Its high intensity is due to the good alignment of the aptamer with the Au surface of nanoparticles [49], in contrast to the lower signal recorded for the case of the free thymine DNA in water [50].…”

Evolution of Complex Target SELEX to Identify Aptamers against Mammalian Cell-Surface Antigens

“…These properties are unique to aptamers, and they have been successfully utilized in designing new versatile molecules aimed at a multitude of applications [ 15 , 16 , 17 , 18 , 19 ]. Most importantly, recent advances in oligonucleotide-based therapeutics, such as antisense technology and microRNA therapeutics, have spurred a renewed demand for the development of novel aptamer-based targeting molecules [ 20 , 21 , 22 ]. Utilization of NAAs as carriers of siRNA or microRNA can eliminate tedious conjugation methods, thus allowing one molecule to serve as both the drug and targeting agent.…”

Aptamers, the Nucleic Acid Antibodies, in Cancer Therapy

“…Not only can aptamers be selected to target and inhibit cancer-specific molecules, but they can also be selected to recognize the surface structures of specific cell types and some of them can be endocytosed or taken in by the cells. The latter properties can be employed to deliver therapeutic agents such as cytotoxic drugs and therapeutic RNAs selectively into cancer cells to exert their activities while avoiding damaging normal cells [114][115][116][117]. Aptamers used for drug delivery mostly target cell membrane receptors that can internalize upon ligand binding, and successful deliveries of a variety of cargoes targeting different receptors have been reported to date [118] (see Figure 2).…”