The Dual-Response-Single-Amplification Fluorescent Nanomachine for Tumor Imaging and Gastric Cancer Diagnosis

Nanomaterials in the diagnosis and treatment of gastrointestinal tumors: New clinical choices and treatment strategies

Nanomaterials have emerged as a promising modality in the diagnosis and treatment of gastrointestinal (GI) tumors, offering significant advancements over conventional methods. In diagnostic applications, nanomaterials facilitate enhanced imaging techniques, including magnetic resonance imaging (MRI), computed tomography (CT), and fluorescence imaging, which provide improved resolution and more accurate detection of early-stage cancers. Nanoparticles (NPs), such as liposomes, dendrimers, and quantum dots, are increasingly employed for the targeted imaging of specific biomarkers associated with GI malignancies, thereby enhancing diagnostic sensitivity and specificity. Liposomes are primarily used for drug delivery due to their ability to encapsulate hydrophobic drugs, dendrimers are useful for both drug delivery and gene therapy due to their highly branched structure, and quantum dots are primarily used in imaging and diagnostics because of their fluorescent properties. We also discuss their respective advantages and limitations. In therapeutic contexts, nanomaterials play a pivotal role in the development of targeted drug delivery systems. These systems address the limitations of traditional chemotherapy by improving drug bioavailability, reducing systemic toxicity, and promoting selective accumulation at tumor sites via both passive and active targeting mechanisms. Nanomedicines, including NPs and nanocarriers, enable the precise delivery of chemotherapeutic agents, nucleic acid -based therapies, and immunomodulators directly to cancer cells, thereby optimizing therapeutic efficacy. Furthermore, nanotechnology offers the potential to modulate the tumor microenvironment (TME), a critical factor in overcoming challenges related to tumor resistance and metastasis. Despite these promising advancements, several challenges persist, including concerns regarding long-term toxicity, stability, and regulatory approval. Nonetheless, the integration of nanomaterials into clinical practice holds substantial potential for revolutionizing the management of GI cancers, paving the way for more precise, personalized, and effective therapeutic strategies.

Biomimetic Synthesis of Nanomachine Inspired from Neutrophil Extracellular Traps for Multimodal Antibacterial Application

Bacterial infections, especially drug-resistant bacterial infections, are causing increasing harm in clinical practice, and there is an urgent need to develop effective antimicrobial materials. Biomimetic DNA nanomachines have attracted much attention due to their flexible design, precise control, and high biocompatibility, but their use for bacterial inhibition has not been reported. Neutrophil extracellular traps (NETs), a network structure released by neutrophils with good bactericidal function, can be used as a superior biomimetic object for the construction of functional bacterial inhibition materials. In this study, Y-shaped DNA was polymerized using magnesium ions to develop reticulated DNA structures, which were used as templates to synthesize copper nanoclusters, leading to the construction of compositionally well-defined and simple reticulated DNA nanomachines. The nanomachine had a three-dimensional, reticular structure similar to that of NETs and especially had excellent antibacterial activity. More importantly, the NETs-imitated nanomachine had a multimodal bacterial inhibition mechanism. The nanomachine could target and localize around the bacteria and eliminate the biofilm, and then the DNA network structure effectively trapped and aggregated the bacteria and caused damage to the bacterial morphology and membrane structure; at the same time, the reticulated DNA nanomachine could also damage the bacterial membrane, causing the degradation and leakage of the proteins and the cellular contents and breakage of the DNA structure, ultimately causing irreversible inhibition of the bacteria. Importantly, the developed nanomachines with high biocompatibility could be used as antimicrobial biomaterials for the efficient treatment and healing of skin wounds infected with bacteria. This study develops a biomimetic DNA nanomachine that can be an excellent antibacterial biomaterial, which expands the application of DNA nanomachine in bacteriostatic and therapeutic fields; it is also an improved biomimetic NETs biomaterial, which brings distinctive design sources for biomimetic materials.

Size-Coded Hydrogel Microbeads for Extraction-Free Serum Multi-miRNAs Quantifications with Machine-Learning-Aided Lung Cancer Subtypes Classification

Classifying lung cancer subtypes, which are characterized by multi-microRNAs (miRNAs) upregulation, is important for therapy and prognosis evaluation. Liquid biopsy is a promising approach, but the pretreatment of RNA extraction is labor-intensive and impairs accuracy. Here we develop size-coded hydrogel microbeads for extraction-free quantification of miR-21, miR-205, and miR-375 directly from serum. The hydrogel microbead is immobilized with an miRNA capture probe, which well retains target miRNA and provides good nonfouling capability for nonspecific biomolecules in serum. The porous structure of microbeads allows efficient DNA cascade amplification reaction and generates a fluorescence signal. The microbeads are clustered into three groups according to size via flow cytometry sorting, and the group fluorescence is integrated for the corresponding miRNA quantification. With machine-learning-assisted data analysis, it achieves good lung cancer diagnosis accuracy and 80% accuracy for subtype classification for 108 serum samples, including lung cancer patients and healthy controls.

Machine learning-assisted pattern recognition and imaging of multiplexed cancer cells via a porphyrin-embedded dendrimer array

Early cancer detection plays a vital role in improving the survival rate of cancer patients, underscoring the importance of developing cancer detection methods. However, it is a great challenge to achieve simple, rapid, and accurate methods for simultaneously discerning various cancers. Herein we developed a 5-element porphyrin-embedded dendrimer-based sensor array, targeting the parallel discrimination of multiple cancers. The porphyrin-embedded dendrimers were modified with various functional groups to generate differentiated interactions with diverse cancer cells, which has been validated by fluorescence responses and laser confocal microscopy imaging. The dual-channel, five-element array, featuring ten signal outputs, achieved 100% accuracy in distinguishing between one human normal cell and six human cancerous cells, as well as in differentiating among mixed cells. Moreover, the screen 6-channel array can accurately distinguish 9 cells from mice and humans in minutes through optimization by multiple machine learning algorithms, including two normal cells and 7 cancerous cells with only 1000 cells, highlighting the significant potential of a porphyrin-embedded dendrimer-based parallel discriminating platform in early cancer diagnosis.

Potential Probes for Targeted Intraoperative Fluorescence Imaging in Gastric Cancer

Gastric cancer (GC) is a malignant tumor of the gastrointestinal tract associated with high mortality rates and accounting for approximately 1 million new cases diagnosed annually. Surgery, particularly radical gastrectomy, remains the primary treatment; however, there are currently no specific approaches to better distinguish malignant from healthy tissue or to differentiate between metastatic and non-metastatic lymph nodes. As a result, surgeons have to remove all lymph nodes indiscriminately, increasing intraoperative risks for patients and prolonging hospital stay. Near-infrared fluorescence imaging with indocyanine green (ICG) can provide real-time visualization of the surgical field using both conventional laparoscopy and robotic mini-invasive precision surgery platforms. However, its application shows some limits, as ICG is a non-targeted contrast agent. Several studies are now investigating the potential efficacy of fluorescent targeted agents that could selectively bind to the tumor tissue, offering a valuable tool for metastatic mapping during robotic gastrectomy. This review aims to summarize the key fluorescent agents that have been developed to recognize GC markers, as well as those targeting the tumor microenvironment (TME) and metabolic features. These agents hold great potential as valuable tools for enhancing precision surgery in robotic gastrectomy procedures improving the clinical recovery of GC patients.

Introduction to Special Issue "The Self-Assembly and Design of Polyfunctional Nanosystems 3.0"

Stimulus-responsive systems allowing for the controlled release of drugs [...].

A sandwich-type photoelectrochemical biosensor based on anthocyanin-sensitized ZnO/P5FIn heterojunction for the sensitive detection of CYFRA21-1

. A sandwich-type photoelectrochemical (PEC) immunosensor based on a ZnO/poly(5-formylindole) (P5FIn)/anthocyanin heterostructure was developed to achieve sensitive background-free detection of the tumor marker CYFRA21-1. ZnO with good photovoltaic properties is combined with narrow bandgap P5FIn to form a p-n type heterojunction. This structure reduces the electron-hole pair recombination, thereby enhancing the photocurrent response of the composite. Anthocyanidins are environmentally friendly natural compounds with excellent antioxidant, redox properties, and remarkable electrochemical activity. After sensitization by anthocyanins, the absorption and utilization of visible light in the composites are enhanced, further improving the PEC luminescence efficiency of the materials. Additionally, boron nitride quantum dots (BN QDs) are combined with Ab2 via polydopamine (PDA) as a secondary antibody marker, enhancing its sensitivity. The biosensor exhibited a linear detection range of 0.001-100 ng mL-1 with a limit of detection (LOD) of 0.00033 ng mL-1. Furthermore, this biosensor demonstrates excellent selectivity, reproducibility, and stability, as well as successful results in analyzing actual human serum samples. This approach provides a feasible method for tumor marker detection.

Current advance of nanotechnology in diagnosis and treatment for malignant tumors

Cancer remains a significant risk to human health. Nanomedicine is a new multidisciplinary field that is garnering a lot of interest and investigation. Nanomedicine shows great potential for cancer diagnosis and treatment. Specifically engineered nanoparticles can be employed as contrast agents in cancer diagnostics to enable high sensitivity and high-resolution tumor detection by imaging examinations. Novel approaches for tumor labeling and detection are also made possible by the use of nanoprobes and nanobiosensors. The achievement of targeted medication delivery in cancer therapy can be accomplished through the rational design and manufacture of nanodrug carriers. Nanoparticles have the capability to effectively transport medications or gene fragments to tumor tissues via passive or active targeting processes, thus enhancing treatment outcomes while minimizing harm to healthy tissues. Simultaneously, nanoparticles can be employed in the context of radiation sensitization and photothermal therapy to enhance the therapeutic efficacy of malignant tumors. This review presents a literature overview and summary of how nanotechnology is used in the diagnosis and treatment of malignant tumors. According to oncological diseases originating from different systems of the body and combining the pathophysiological features of cancers at different sites, we review the most recent developments in nanotechnology applications. Finally, we briefly discuss the prospects and challenges of nanotechnology in cancer.

A Universal Strategy for Enhancing the Circulating miRNAs' Detection Performance of Rolling Circle Amplification by Using a Dual-Terminal Stem-Loop Padlock

Rolling circle amplification (RCA) is one of the most promising nucleic acid detection technologies and has been widely used in the molecular diagnosis of disease. Padlock probes are often used to form circular templates, which are the core of RCA. However, RCA often suffers from insufficient specificity and sensitivity. Here we report a reconstruction strategy for conventional padlock probes to promote their overall performance in nucleic acid detection while maintaining probe functions uncompromised. When two rationally designed stem-loops were strategically placed at the two terminals of linear padlock probes, the specificity of target recognition was enhanced and the negative signal was significantly delayed. Our design achieved the best single-base discrimination compared with other structures and over a 1000-fold higher sensitivity than that of the conventional padlock probe, validating the effectiveness of this reconstruction. In addition, the underlying mechanisms of our design were elucidated through molecular dynamics simulations, and the versatility was validated with longer and shorter padlocks targeting the same target, as well as five additional targets (four miRNAs and dengue virus - 2 RNA mimic (DENV-2)). Finally, clinical applicability in multiplex detection was demonstrated by testing real plasma samples. Our exploration of the structures of nucleic acids provided another perspective for developing high-performance detection systems, improving the efficacy of practical detection strategies, and advancing clinical diagnostic research.