The effective transfection of a low dose of negatively charged drug-loaded DNA-nanocarriers into cancer cells via scavenger receptors
Authors: Ammara Saleem
Jahanzeb Mudassir
Chengfei Zhang
Mirza Muhammad Faran Ashraf Baig
Muhammad Furqan Akhtar
Journal: Journal of Pharmaceutical Analysis (2021)
Discipline: PHARMACOLOGY & TOXICOLOGY
Keywords: Cisplatin (CPT); DNA-nanowires (DNA-NWs); HepG2 resistant cancer cells; Scavenger receptors.
Affiliations: Laboratory of Biomedical & Pharmaceutical Engineering of Stem Cells Research, Restorative Dental Sciences, Faculty of Dentistry, The University of Hong Kong, 999077, Hong Kong, PR China., Riphah Institute of Pharmaceutical Sciences, Riphah International University, Lahore, Pakistan., Department of Pharmacology, Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan., Faculty of Pharmacy, Bahauddin Zakariya University, Multan, 60000, Pakistan.

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 &lt; 75% for 6 h in the presence of serum, demonstrating suitability for systemic applications. The IC50 of CPT@DNA-NWs was reduced to 12.8 nM CPT, as compared with the free CPT solution exhibiting an IC50 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. 

Retracted: No

PubPeer comments:
 In this paper, DNA nanowires loaded with Cisplatin are described, and Figure 4 B shows the confocal images. However, the images in Figure 4B appear to show the same specimens as published in at least 3 other papers by the same first author, where they represent different compounds. The other papers are: * Mirza Muhammad Faran Ashraf Baig and Xing-Hua Xia, Applied Nanoscience (2020), DOI: 10.1007 s13204-020-01293-2 - https: pubpeer.com publications 1019754110D74381242E47B7FA5572 - showing Carboplatin (CRPT)-based DNA-nanowires * Mirza Muhammad Faran Ashraf Baig et al. Drug Delivery and Translational Research (2020), DOI: 10.1007 s13346-020-00820-6 - https: pubpeer.com publications 01794C3A20849640AEC54C15A8B99E - showing Camptothecin (CMPT)-based DNA nanofibers * Mirza Muhammad Faran Ashraf Baig et al., Journal of Molecular Liquids (2020), DOI: 10.1016 j.molliq.2020.113785 - https: pubpeer.com publications 7BF60F063AAE7C5D021A1318B1FDDC - showing Bleomycin-loaded DNA-nanotubes Overlapping areas are shown with boxes of the same color. Here is Figure 4 of this paper and the figures 4 of the other papers: ![file] ![file] Can the author please clarify how these different compounds can show such similar images? , 
 Figure 6 raises some concerns too. I have marked several areas that look repetitive, without trying to be comprehensive. ![file] , 
 Figure 7 raises some concerns too. I have marked several areas that look repetitive, without trying to be comprehensive. ![file] , 
 ![file] ![file] 2017 nanoscope exported tiff images. could not attach. Screen shot is here , 
 In Figure 7A, there are some regions that appeared with square dark areas (indicated by yellow arrows) in the blue channel (left image). Surprisingly, the cell nuclei in the blue channel (left image, pointed by red arrows) did not appear in the merged image (right image). So, can the author explain why the cell nuclei in the blue image were **TOTALLY** different from the merged one? ![file] , 
 First of all thank you. As an explanation, The blue panel was at different location. But purpose was just to show how the nucleus look like. And how the cell membrane look like. And how the membrane and nucleus merged image look like. You have advanced softwares. Humans may have errors. , 
 Sorry, I had many many AFM images. But I thought all look similar. And after overall functionlization, also look similar. So it was my ignorennce to show the similar morphology again and again with some alterations. But it s reality that nanotubes (or nanowires and nanofiebrs etc) all look like similar. I have provided more AFM images to show. , 
 #2 Fig 6 again: ![] Possibly derived from Fig 5a of [Zhang et al (2021)] ,  Flow cytometric analysis of HepG 2 cells incubated with Lipo-VM (15 u03bcM) for 12 h and then stained with Annexin V-FITC and PI. Cells treated with PBS and empty liposomes respectively were given as negative controls . ![file] Here, for instance, the two Blank panels: ![file] , 
 The retraction request has been sent to the editor-in-chief. ,