Anti-miR21-conjugated DNA nanohydrogel for enhanced cancer therapy.

MicroRNAs (miRNAs) are non-coding, endogenous small single-stranded RNA molecules involved in post-transcriptional regulation of gene expression. It has been demonstrated that dysregulation of miRNA plays a major role in tumor formation, proliferation, and metastasis. Therefore, the delivery of anti-miRNA oligonucleotides to block the activity of these oncogenic miRNAs is a high-potential anti-cancer therapy approach.

Recent Advances and Prospects of Nucleic Acid Therapeutics for Anti-Cancer Therapy.

Nucleic acid therapeutics are promising alternatives to conventional anti-cancer therapy, such as chemotherapy and radiation therapy. While conventional therapies have limitations, such as high side effects, low specificity, and drug resistance, nucleic acid therapeutics work at the gene level to eliminate the cause of the disease. Nucleic acid therapeutics treat diseases in various forms and using different mechanisms, including plasmid DNA (pDNA), small interfering RNA (siRNA), anti-microRNA (anti-miR), microRNA mimics (miRNA mimic), messenger RNA (mRNA), aptamer, catalytic nucleic acid (CNA), and CRISPR cas9 guide RNA (gRNA).

Nanosized DNA Hydrogel Functionalized with a DNAzyme Tetrahedron for Highly Efficient Gene Silencing.

DNAzymes are DNA oligonucleotides that have catalytic activity without the assistance of protein enzymes. In particular, RNA-cleaving DNAzymes were considered as ideal candidates for gene therapy due to their unique characteristics. Nevertheless, efforts to use DNAzyme as a gene therapeutic agent are limited by issues such as their low physiological stability in serum and intracellular delivery efficiency.

Systematic Selection of High-Affinity ssDNA Sequences to Carbon Nanotubes.

Single-walled carbon nanotubes (SWCNTs) have gained significant interest for their potential in biomedicine and nanoelectronics. The functionalization of SWCNTs with single-stranded DNA (ssDNA) enables the precise control of SWCNT alignment and the development of optical and electronic biosensors. This study addresses the current gaps in the field by employing high-throughput systematic selection, enriching high-affinity ssDNA sequences from a vast random library.

Recent Advances in Biological Applications of Aptamer-Based Fluorescent Biosensors.

Aptamers have been spotlighted as promising bio-recognition elements because they can be tailored to specific target molecules, bind to targets with a high affinity and specificity, and are easy to chemically synthesize and introduce functional groups to. In particular, fluorescent aptasensors are widely used in biological applications to diagnose diseases as well as prevent diseases by detecting cancer cells, viruses, and various biomarkers including nucleic acids and proteins as well as biotoxins and bacteria from food because they have the advantages of a high sensitivity, selectivity, rapidity, a simple detection process, and a low price. We introduce screening methods for isolating aptamers with q high specificity and summarize the sequences and affinities of the aptamers in a table.

Advances and Trends in miRNA Analysis Using DNAzyme-Based Biosensors.

miRNAs are endogenous small, non-coding RNA molecules that function in post-transcriptional regulation of gene expression. Because miRNA plays a pivotal role in maintaining the intracellular environment, and abnormal expression has been found in many cancer diseases, detection of miRNA as a biomarker is important for early diagnosis of disease and study of miRNA function. However, because miRNA is present in extremely low concentrations in cells and many types of miRNAs with similar sequences are mixed, traditional gene detection methods are not suitable for miRNA detection.

Investigation of artificial intelligence integrated fluorescence endoscopy image analysis with indocyanine green for interpretation of precancerous lesions in colon cancer.

Indocyanine green (ICG) has been used in clinical practice for more than 40 years and its safety and preferential accumulation in tumors has been reported for various tumor types, including colon cancer. However, reports on clinical assessments of ICG-based molecular endoscopy imaging for precancerous lesions are scarce. We determined visualization ability of ICG fluorescence endoscopy in colitis-associated colon cancer using 30 lesions from an azoxymethane/dextran sulfate sodium (AOM/DSS) mouse model and 16 colon cancer patient tissue-samples.

Zwitterion-Coated Colloidal Magnetic Nanoparticle Clusters for Reduced Nonspecific Adsorption of Biomolecules.

This paper demonstrates fabrication of silica-shell-coated magnetic nanoparticle clusters (SMNCs) and subsequent surface engineering of SMNCs to produce surface-modified SMNCs that have zwitterionic and primary amine ligands (SMNC-ZW/Am). SMNC-ZW/Am was passivated by zwitterionic ligands for improved colloidal stability and reduced nonspecific adsorption and by primary amine ligands for facilitated conjugation with biomolecules. Hydrodynamic (HD) size and zeta potential of SMNC-ZW/Am could be flexibly tuned by controlling the relative amounts of zwitterionic and primary amine ligands.

Controlled Photoinduced Electron Transfer from InP/ZnS Quantum Dots through Cu Doping: A New Prototype for the Visible-Light Photocatalytic Hydrogen Evolution Reaction.

Photoexcited electron extraction from semiconductors can be useful for converting solar energy into useful forms of energy. Although InP quantum dots (QDs) are considered alternative materials for solar energy conversion, the inherent instability of bare InP QDs demands the use of passivation layers such as ZnS for practical applications, which impedes carrier extraction from the QDs. Here, we demonstrate that Cu-doped InP/ZnS (InP/Cu:ZnS) QDs improve the electron transfer ability due to hole capture by Cu dopants.

Longitudinal shape evolution of AgS nanoparticles from nanospheres, rhombic dodecahedrons, nanorods, to nanocubes.

Longitudinal shape evolution of AgS nanoparticles is reported. Initially 9 nm nanospheres turn into faceted rhombic dodecahedrons and elongate to minimize surface energy. The elongated rhombic dodecahedrons show oriented attachments to 〈-104〉 directions sequentially yielding dimers, linear oligomers, and nanorods.

Colloidal Porous AuAg Alloyed Nanoparticles for Enhanced Photoacoustic Imaging.

Colloidal porous AuAg alloyed nanoparticles (pAuAgNPs) were synthesized by galvanic replacement reaction from Ag nanocubes. pAuAgNPs have a 50 nm exterior diameter and half of their inner space consists of voids that have a bimodal size distribution with peaks at 21 and 8.3 nm.

Evolution from unimolecular to colloidal-quantum-dot-like character in chlorine or zinc incorporated InP magic size clusters.

Magic-sized clusters (MSCs) can be isolated as intermediates in quantum dot (QD) synthesis, and they provide pivotal clues in understanding QD growth mechanisms. We report syntheses for two families of heterogeneous-atom-incorporated InP MSCs that have chlorine or zinc atoms. All the MSCs could be directly synthesized from conventional molecular precursors.

Reversibly pH-responsive gold nanoparticles and their applications for photothermal cancer therapy.

Microenvironment responsive nanomaterials are attractive for therapeutic applications with regional specificity. Here we report pH responsive gold nanoparticles which are designed to aggregate in acidic condition similar to cancer environment and returned to its original disassembled states in a physiological pH. The pH responsive behavior of the particles is derived by change of electrostatic interaction among the particles where attraction and repulsion play a major role in low and high pH of the environment, respectively.

Synthesis of far-red- and near-infrared-emitting Cu-doped InP/ZnS (core/shell) quantum dots with controlled doping steps and their surface functionalization for bioconjugation.

In this study, we designed and synthesized far-red- and near-infrared-emitting Cu-doped InP-based quantum dots (QDs), and we also demonstrated their highly specific and sensitive biological imaging ability. Cu-doped InP/ZnS (core/shell) QDs were prepared using the hot colloidal synthesis method in the organic phase. The ZnS shell passivates the surface and improves the photoluminescence (PL) intensity.

Tumor-Associated Macrophages Enhance Tumor Hypoxia and Aerobic Glycolysis.

Tumor hypoxia and aerobic glycolysis are well-known resistance factors for anticancer therapies. Here, we demonstrate that tumor-associated macrophages (TAM) enhance tumor hypoxia and aerobic glycolysis in mice subcutaneous tumors and in patients with non-small cell lung cancer (NSCLC). We found a strong correlation between CD68 TAM immunostaining and PET fluoro-deoxyglucose (FDG) uptake in 98 matched tumors of patients with NSCLC.

Synthesis of Ag/Mn Co-Doped CdS/ZnS (Core/Shell) Nanocrystals with Controlled Dopant Concentration and Spatial Distribution and the Dynamics of Excitons and Energy Transfer between Co-Dopants.

We report lightly Ag/Mn co-doped CdS/ZnS (core/shell) nanocrystals (NCs) as a model system for studying interactions between co-dopants and between NCs and dopants. The co-doped NCs were prepared with a varying average number of Ag dopant atoms per CdS core of the NC from zero to eight; at the same time, the depth profile of the Mn dopants in the ZnS shells was controlled to be either close to or far from the Ag dopants. The incorporation of an average of one to two Ag dopant atoms per NC increased the band-edge photoluminescence (PL); however, it was quenched at higher doping concentration.

Multiplexed In Vivo Imaging Using Size-Controlled Quantum Dots in the Second Near-Infrared Window.

PbS/CdS core/shell quantum dots (QDs) that emit at the second near-infrared (NIR-II, 1000-1700 nm) window are synthesized. The PbS seed size and CdS shell thicknesses are carefully controlled to produce bright and narrow fluorescence that are suitable for multiplexing. A polymer encapsulation yields polymer-encapsulated NIR-II QDs (PQDs), which provides the QDs with long-term fluorescence stability over a week in biological media.

Multi-Spectral Fluorescence Imaging of Colon Dysplasia InVivo Using a Multi-Spectral Endoscopy System.

Background And Study Aim: To develop a molecular imaging endoscopic system that eliminates tissue autofluorescence and distinguishes multiple fluorescent markers specifically on the cancerous lesions.

Methods: Newly developed multi-spectral fluorescence endoscope device has the potential to eliminate signal interference due to autofluorescence and multiplex fluorophores in fluorescent probes. The multiplexing capability of the multi-spectral endoscope device was demonstrated in the phantom studies and multi-spectral imaging with endoscopy and macroscopy was performed to analyze fluorescence signals after administration of fluorescent probe that targets cancer in the colon.

Heterojunction Area-Controlled Inorganic Nanocrystal Solar Cells Fabricated Using Supra-Quantum Dots.

A supra-quantum dot (SQD) is a three-dimensional structure formed by the attachment of quantum dots. The SQDs have sizes of tens of nanometer and they maintain the characteristics of the individual quantum dots fairly well. Moreover, their sizes and elemental compositions can be tuned precisely.

A RNA producing DNA hydrogel as a platform for a high performance RNA interference system.

RNA interference (RNAi) is a mechanism in which small interfering RNA (siRNA) silences a target gene. Herein, we describe a DNA hydrogel capable of producing siRNA and interfering with protein expression. This RNAi-exhibiting gel (termed I-gel for interfering gel) consists of a plasmid carrying the gene transcribing siRNA against the target mRNA as part of the gel scaffold.