Trifunctional Graphene Quantum Dot@LDH Integrated Nanoprobes for Visualization Therapy of Gastric Cancer

Visualization of microRNA therapy in cancers delivered by small extracellular vesicles

MicroRNA (miRNA) delivery by extracellular vesicles (EVs) has recently inspired tremendous developments in cancer treatments. However, hybridization between miRNA and its target mRNA is still difficult to be imaged in vivo to assess the therapeutic effects in time. Herein we design a nano-scale fluorescent "off-on" complex encapsulated by small extracellular vesicles (sEVs) for real-time visualization and evaluation of gene therapy efficiency in human gastric cancer cells and murine xenograft tumor models. The complex is formed by π-π stacking between graphene quantum dots (GQDs) and tumor suppressor miR-193a-3p conjugated fluorescent tag whose signals remain off when binding to GQDs. Loaded into sEVs using tunable sonication techniques, the GQDs/Cy5-miR particles enter the tumor cells and promote miR-193a-3p escape from endosomes. The miR-193a-3p in GQDs/Cy5-miR is unleashed to pair the specific target oncogene cyclin D1 (CCND1), therefore turning on the fluorescence of miRNA tags. We find out that GQDs/Cy5-miR@sEVs can activate the "turn-on" fluorescent signal and exhibit the longest retention time in vivo, which suggests a minimized degradation of miR-193a-3p in dynamic processes of miRNA-mRNA binding. More importantly, GQDs/Cy5-miR@sEVs significantly promote cancer apoptosis in vitro and in vivo via the enhanced cellular uptake. Our study demonstrates that GQDs/Cy5-miR@sEVs represent an efficient and refined theranostic platform for gene therapy in cancers.

Long noncoding RNA NONHSAT160169.1 promotes resistance via hsa-let-7c-3p/SOX2 axis in gastric cancer

In clinical trials involving patients with HER2 (ERBB2 receptor tyrosine kinase 2) positive gastric cancer, the efficacy of the HER2-targeted drug lapatinib has proven to be disappointingly poor. Under the persistent pressure exerted by targeted drug therapy, a subset of tumor cells exhibit acquired drug resistance through the activation of novel survival signaling cascades, alongside the proliferation of tumor cells that previously harbored mutations conferring resistance to the drug. This study was undertaken with the aim of elucidating in comprehensive detail the intricate mechanisms behind adaptive resistance and identifying novel therapeutic targets that hold promise in the development of effective lapatinib-based therapies for the specific subset of patients afflicted with gastric cancer. We have successfully established a gastric cancer cell line with acquired lapatinib resistance, designated as HGC-27-LR cells. Utilizing comprehensive coding and noncoding transcriptome sequencing analysis, we have identified key factors that regulate lapatinib resistance in HGC-27 cells. We have compellingly validated that among all the lncRNAs identified in HGC-27-LR cells, a novel lncRNA (long noncoding RNA) named NONHSAT160169.1 was found to be most notably upregulated following exposure to lapatinib treatment. The upregulation of NONHSAT160169.1 significantly augmented the migratory, invasive, and stemness capabilities of HGC-27-LR cells. Furthermore, we have delved into the mechanism by which NONHSAT160169.1 regulates lapatinib resistance. The findings have revealed that NONHSAT160169.1, which is induced by the p-STAT3 (signal transducer and activator of transcription 3) nuclear transport pathway, functions as a decoy that competitively interacts with hsa-let-7c-3p and thereby abrogates the inhibitory effect of hsa-let-7c-3p on SOX2 (SRY-box transcription factor 2) expression. Hence, our study has unveiled the NONHSAT160169.1/hsa-let-7c-3p/SOX2 signaling pathway as a novel and pivotal axis for comprehending and surmounting lapatinib resistance in the treatment of HER2-positive gastric cancer.

Four Ounces Can Move a Thousand Pounds: The Enormous Value of Nanomaterials in Tumor Immunotherapy

The application of nanomaterials in healthcare has emerged as a promising strategy due to their unique structural diversity, surface properties, and compositional diversity. In particular, nanomaterials have found a significant role in improving drug delivery and inhibiting the growth and metastasis of tumor cells. Moreover, recent studies have highlighted their potential in modulating the tumor microenvironment (TME) and enhancing the activity of immune cells to improve tumor therapy efficacy. Various types of nanomaterials are currently utilized as drug carriers, immunosuppressants, immune activators, immunoassay reagents, and more for tumor immunotherapy. Necessarily, nanomaterials used for tumor immunotherapy can be grouped into two categories: organic and inorganic nanomaterials. Though both have shown the ability to achieve the purpose of tumor immunotherapy, their composition and structural properties result in differences in their mechanisms and modes of action. Organic nanomaterials can be further divided into organic polymers, cell membranes, nanoemulsion-modified, and hydrogel forms. At the same time, inorganic nanomaterials can be broadly classified as nonmetallic and metallic nanomaterials. The current work aims to explore the mechanisms of action of these different types of nanomaterials and their prospects for promoting tumor immunotherapy.

Zero-Dimensional Carbon Nanomaterials for Fluorescent Sensing and Imaging

Advances in nanotechnology and nanomaterials have attracted considerable interest and play key roles in scientific innovations in diverse fields. In particular, increased attention has been focused on carbon-based nanomaterials exhibiting diverse extended structures and unique properties. Among these materials, zero-dimensional structures, including fullerenes, carbon nano-onions, carbon nanodiamonds, and carbon dots, possess excellent bioaffinities and superior fluorescence properties that make these structures suitable for application to environmental and biological sensing, imaging, and therapeutics. This review provides a systematic overview of the classification and structural properties, design principles and preparation methods, and optical properties and sensing applications of zero-dimensional carbon nanomaterials. Recent interesting breakthroughs in the sensitive and selective sensing and imaging of heavy metal pollutants, hazardous substances, and bioactive molecules as well as applications in information encryption, super-resolution and photoacoustic imaging, and phototherapy and nanomedicine delivery are the main focus of this review. Finally, future challenges and prospects of these materials are highlighted and envisaged. This review presents a comprehensive basis and directions for designing, developing, and applying fascinating fluorescent sensors fabricated based on zero-dimensional carbon nanomaterials for specific requirements in numerous research fields.

Engineered Polymeric Nanovector for Intracellular Peptide Delivery in Antitumor Therapy

Objective

This study aimed to deliver a polypeptide from the Bax-BH3 domain (BHP) through the synthesis of self-assembled amphiphile nanovectors (NVs) and to assess their potential for cancer therapeutic applications and biological safety in vitro and in vivo. These findings provide valuable options for cancer intervention and a novel approach for the rational design of therapeutics.

Methods

We studied the antitumor activity of BHP by preparing RGDfK-PHPMA-b-Poly (MMA-alt-(Rhob-MA)) (RPPMMRA) and encapsulating it in BHP-NV. We also performed a series of characterizations and property analyses of RPPMMRA, including its size, stability, and drug-carrying capacity. The biocompatibility of RPPMMRA was evaluated in terms of cytotoxicity and hemolytic effects. The pro-apoptotic capacity of BHP was evaluated in vitro using mitochondrial membrane potential, flow cytometry, and apoptosis visualization techniques. The potential therapeutic effects of BHP on tumors were explored using reverse molecular docking. We also investigated the in vivo proapoptotic effect of BHP-NV in a nude mouse tumor model.

Results

NVs were successfully prepared with hydrated particle sizes ranging from 189.6 nm to 256.6 nm, spherical overall, and were able to remain stable in different media for 72 h with drug loading up to 15.2%. The NVs were be successfully internalized within 6 h with good biocompatibility. Neither BHP nor NV showed significant toxicity when administered alone, however, BHP-NV demonstrated significant side effects in vitro and in vivo. The apoptosis rate increased significantly from 14.13% to 66.34%. Experiments in vivo showed that BHP-NV exhibited significant apoptotic and tumor-suppressive effects.

Conclusion

A targeted fluorescent NV with high drug delivery efficiency and sustained release protected the active center of BHP, constituting BHP-NV for targeted delivery. RPPMMRA demonstrated excellent biocompatibility, stability, and drug loading ability, whereas and BHP-NV demonstrated potent antitumor effects in vivo and in vitro.

Facile Synthesis of Basic Copper Carbonate Nanosheets for Photoacoustic Imaging-Guided Tumor Apoptosis and Ferroptosis and the Extension Exploration of the Synthesis Method

Elimination of tumor cells using carbonate nanomaterials with tumor microenvironment-responsive capacity has been explored as an effective strategy. However, their therapeutic outcomes are always compromised by the relatively low intratumoral accumulation and limited synthesis method. Herein, a novel kind of basic copper carbonate nanosheets was designed and prepared using a green synthesis method for photoacoustic imaging-guided tumor apoptosis and ferroptosis therapy. These nanosheets were synthesized with the assistance of dopamine and ammonium bicarbonate (NH4HCO3) and the loading of glucose oxidase (GOx). NH4HCO3 could not only provide an alkaline environment for the polymerization of dopamine but also supply carbonates for the growth of nanosheets. The formed nanosheets displayed good acid and near-infrared light responsiveness. After intercellular uptake, they could be degraded to release Cu2+ and GOx, generating hydroxyl radicals through a Cu+-mediated Fenton-like reaction, consuming glucose, up-regulating H2O2 levels, and down-regulating GSH levels. Tumor elimination could be achieved by hydroxyl radical-induced apoptosis and ferroptosis. More amusingly, this synthesis method can be extended to several kinds of mono-element and multi-element carbonate nanomaterials (e.g., Fe, Mn, and Co), showing great potential for further tumor theranostics.

Functional Materials for Subcellular Targeting Strategies in Cancer Therapy: Progress and Prospects

Neoadjuvant and adjuvant therapies have made significant progress in cancer treatment. However, tumor adjuvant therapy still faces challenges due to the intrinsic heterogeneity of cancer, genomic instability, and the formation of an immunosuppressive tumor microenvironment. Functional materials possess unique biological properties such as long circulation times, tumor-specific targeting, and immunomodulation. The combination of functional materials with natural substances and nanotechnology has led to the development of smart biomaterials with multiple functions, high biocompatibilities, and negligible immunogenicities, which can be used for precise cancer treatment. Recently, subcellular structure-targeting functional materials have received particular attention in various biomedical applications including the diagnosis, sensing, and imaging of tumors and drug delivery. Subcellular organelle-targeting materials can precisely accumulate therapeutic agents in organelles, considerably reduce the threshold dosages of therapeutic agents, and minimize drug-related side effects. This review provides a systematic and comprehensive overview of the research progress in subcellular organelle-targeted cancer therapy based on functional nanomaterials. Moreover, it explains the challenges and prospects of subcellular organelle-targeting functional materials in precision oncology. The review will serve as an excellent cutting-edge guide for researchers in the field of subcellular organelle-targeted cancer therapy.

Factors affecting the toxicity and oxidative stress of layered double hydroxide-based nanomaterials in freshwater algae

Layered double hydroxide (LDH) nanomaterials are utilized extensively in numerous fields because of their distinctive structural properties. It is critical to understand the environmental behavior and toxicological effects of LDHs to address potential concerns caused by their release into the environment. In this work, the toxicological effects of two typical LDHs (Mg-Al-LDH and Zn-Al-LDH) on freshwater green algae (Scenedesmus obliquus) and the main affecting factors were examined. The Zn-Al-LDH exhibited a stronger growth inhibition toxicity than the Mg-Al-LDH in terms of median effect concentration. This toxicity difference was connected to the stability of particle dispersion in water and the metallic composition of LDHs. The contribution of the dissolved metal ions to the overall toxicity of the LDHs was lower than that of their particulate forms. Moreover, the joint toxic action of different dissolved metal ions in each LDH belonged to additive effects. The Mg-Al-LDH induced a stronger oxidative stress effect in algal cells than the Zn-Al-LDH, and mitochondrion was the main site of LDH-induced production of reactive oxygen species. Scanning electron microscope observation indicated that both LDHs caused severe damage to the algal cell surface. At environmentally relevant concentrations, the LDHs exhibited joint toxic actions with two co-occurring contaminants (oxytetracycline and nano-titanium dioxide) on S. obliquus in an additive manner mainly. These findings emphasize the impacts of the intrinsic nature of LDHs, the aqueous stability of LDHs, and other environmental contaminants on their ecotoxicological effects.

Application of nanotechnology in the early diagnosis and comprehensive treatment of gastrointestinal cancer

Gastrointestinal cancer (GIC) is a common malignant tumour of the digestive system that seriously threatens human health. Due to the unique organ structure of the gastrointestinal tract, endoscopic and MRI diagnoses of GIC in the clinic share the problem of low sensitivity. The ineffectiveness of drugs and high recurrence rates in surgical and drug therapies are the main factors that impact the curative effect in GIC patients. Therefore, there is an urgent need to improve diagnostic accuracies and treatment efficiencies. Nanotechnology is widely used in the diagnosis and treatment of GIC by virtue of its unique size advantages and extensive modifiability. In the diagnosis and treatment of clinical GIC, surface-enhanced Raman scattering (SERS) nanoparticles, electrochemical nanobiosensors and magnetic nanoparticles, intraoperative imaging nanoparticles, drug delivery systems and other multifunctional nanoparticles have successfully improved the diagnosis and treatment of GIC. It is important to further improve the coordinated development of nanotechnology and GIC diagnosis and treatment. Herein, starting from the clinical diagnosis and treatment of GIC, this review summarizes which nanotechnologies have been applied in clinical diagnosis and treatment of GIC in recent years, and which cannot be applied in clinical practice. We also point out which challenges must be overcome by nanotechnology in the development of the clinical diagnosis and treatment of GIC and discuss how to quickly and safely combine the latest nanotechnology developed in the laboratory with clinical applications. Finally, we hope that this review can provide valuable reference information for researchers who are conducting cross-research on GIC and nanotechnology.

Mulberry-Leaves-Derived Red-Emissive Carbon Dots for Feeding Silkworms to Produce Brightly Fluorescent Silk

Fluorescent silk has promising applications in dazzling textiles, biological engineering, and medical products, but the natural Bombyx mori silk has almost no fluorescence. Here carbon dots (CDs) made from mulberry leaves are reported, which have a strong near-infrared fluorescence with absolute quantum yield of 73% and a full width at half maximum of 20 nm. After feeding with such CDs, silkworms exhibit bright red fluorescence, grow healthily, cocoon normally, and turn to moths finally. The cocoons are pink in daylight and show bright red fluorescence under ultraviolet light. After breaking out of such cocoons, the red-emissive moths can mate and lay fluorescent eggs which would hatch normally. The growth cycle of the second generation of the test silkworm is the same as that of the control group, which means such CDs have excellent biocompatiblility. Dissection and analyses on both the test silkworms and cocoons disclose the metabolic route of the CDs, that is, the fluorescent CDs are absorbed by silkworms from alimentary canals, then transferred to silk glands, and finally to cocoons, while those unabsorbed CDs are excreted with the feces. All experimental results confirm the excellent biocompatibility and fluorescence stability of such CDs.

Structural and spectroscopic characterization of pyrene derived carbon nano dots: a single-particle level analysis

The bottom-up approach has been widely used for large-scale synthesis of carbon nanodots (CNDs). However, the structure and origin of photoluminescence in CNDs synthesized by the bottom-up approach is still a subject of debate. Here, using a series of separation techniques like solvent extraction, column chromatography, gel electrophoresis and dialysis, we present three distinct fluorescent components in CNDs synthesized from pyrene, a well-known precursor molecule. The separated components have qualitative and quantitatively different absorption and emission spectral features including quantum yield (QY). Optical and vibrational spectroscopy techniques combined with electron microscopy indicate that a subtle balance between the extent of graphitization and the presence of molecular fluorophores determines the nature of fluorescence emission. A substantial difference in photons/cycle, single-particle fluorescence blinking, ON-OFF photoswitching strongly supports the distinct nature of the components.