The effective transfection of a low dose of negatively charged drug-loaded DNA-nanocarriers into cancer cells via scavenger receptors

Abstract

DNA-nanotechnology-based nano-architecture scaffolds based on circular strands were designed in the form of DNA-nanowires (DNA-NWs) as a polymer of DNA-triangles. Circularizing a scaffold strand (84-NT) was the critical step followed by annealing with various staple strands to make stiff DNA-triangles. Atomic force microcopy (AFM), native polyacrylamide gel electrophoresis (PAGE), UV-analysis, MTT-assay, flow cytometry, and confocal imaging were performed to assess the formulated DNA-NWs and cisplatin (CPT) loading. The AFM and confocal microscopy images revealed a uniform shape and size distribution of the DNA-NWs, with lengths ranging from 2 to 4 μm and diameters ranging from 150 to 300 nm. One sharp band at the top of the lane (500 bp level) with the loss of electrophoretic mobility during the PAGE (native) gel analysis revealed the successful fabrication of DNA-NWs. The loading efficiency of CPT ranged from 66.85% to 97.35%. MTT and flow cytometry results showed biocompatibility of the blank DNA-NWs even at 95% concentration compared with the CPT-loaded DNA-NWs. The CPT-loaded DNA-NWs exhibited enhanced apoptosis (22%) compared to the apoptosis (7%) induced by the blank DNA-NWs. The release of CPT from the DNA-NWs was sustained at < 75% for 6 h in the presence of serum, demonstrating suitability for systemic applications. The IC 50 of CPT@DNA-NWs was reduced to 12.8 nM CPT, as compared with the free CPT solution exhibiting an IC 50 of 51.2 nM. Confocal imaging revealed the targetability, surface binding, and slow internalization of the DNA-NWs in the scavenger-receptor-rich cancer cell line (HepG2) compared with the control cell line.

DNA-Based Nanostructured Platforms as Drug Delivery Systems

“…CPT-DNA-NWs were biocompatible and exhibited strong cytotoxicity at lower concentrations compared to free CPT where the apoptosis increased to 22% compared to placebo DNA-NWs having only 7% apoptosis. 16 DNA nanostructures can improve the stability, transport, and permeation potential of encapsulated drug to desired site, subsiding the toxic and side effects on normal cells or organs in order to improve the safety and therapeutic efficacy of drug. Zhong constructed DNA nanostructures for cisplatin prodrug delivery.…”

“…CPT@DNA-NWs demonstrated efficient surface binding and internalization in scavengerreceptor-rich HepG2 cells. 16 Abbas et al used a DNA Nanothread to encapsulate Cisplatin and function as a polyanionic ligand to provide targeted cytotoxicity and improved anticancer treatment. CPT hydrogen-bonded to DNA-NT at certain GC-rich sites.…”

“…In tile-based assembly, the DNA triangular tile (multiarm junction) is formed by sticky end cohesion of circularizing DNA strands which self-assemble in 2D superstructures or lattices upon annealing with staple strands. Due to the obvious helical shape and curvature of the DNA, these 2D superstructures may fold and spin upon themselves, resulting in compact 3D DNA nanostructures such as hydrogels, crystals, dendrimer-like DNA nanostructure, etc. , The DNA origami technique utilizes scaffold DNA to design the nanostructure with predefined architecture and utilizes staple strands to hold the structure and subsequently endows functional properties necessary for loading therapeutics and diagnostic payloads . The scope of functional modification, controllable morphology, and precision in fabrications has made this technique an ideal approach for the development of compatible and efficient DNA-based nanostructures for drug delivery and theranostic applications .…”

Development and functionalization of DNA nanostructures for biomedical applications

“…DNA nanostructured self‐assembly and functional optimization open the horizon to biochemical and biomedical applications. DNA‐based targeted therapy is used to treat diseases, such as cancer and immune diseases by selectively targeting diseased cells both in vitro and systemically 95–97 . DNA nanomaterials by efficiently distinguishing host cells against diseased cells by interacting with the biomarkers also enable us to apply for the diagnostic purpose 97–100 .…”

Nucleic acid nanoassembly-enhanced RNA therapeutics and diagnosis

“…Nucleic acid nanoassemblies are usually fabricated by bottom-up construction, and the designer precisely controls each property and step along the way. Theoretically, the researchers assemble any desired structure by nucleic acid sequences 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 . The well-ordered structure and high stability also improved the recognition efficiency and reduced the nonspecific adsorption of RNAs on the biosensing platform 47 .…”