Multiplexed RNA profiling by regenerative catalysis enables blood-based subtyping of brain tumors

A cubic DNA nanocage probe for in situ analysis of miRNA-10b in tumor-derived extracellular vesicles

A cubic DNA nanocage probe is able to enter EVs derived from MDA-MB-231 cells and react with miRNA-10b. The probe-loaded EVs were employed to monitor the process of entry of miRNA-10b into MCF-10A cells, allowing visualization of EV-mediated intercellular communication of miRNA-10b between the cancer cells.

Boosting Enzyme Activity in Enzyme Metal-Organic Framework Composites

Enzymes, as highly efficient biocatalysts, excel in catalyzing diverse reactions with exceptional activity and selective properties under mild conditions. Nonetheless, their broad applications are hindered by their inherent fragility, including low thermal stability, limited pH tolerance, and sensitivity to organic solvents and denaturants. Encapsulating enzymes within metal-organic frameworks (MOFs) can protect them from denaturation in these harsh environments. However, this often leads to a compromised enzyme activity. In recent years, extensive research efforts have been dedicated to enhancing enzymatic activity within MOFs, leading to the development of new enzyme-MOF composites that not only preserve their catalytic potential but also outperform their free counterparts. This Review provides a comprehensive review on recent developments in enzyme-MOF composites with a specific emphasis on their enhanced enzymatic activity compared to free enzymes.

Exosome-tuned MOF signal amplifier boosting tumor exosome phenotyping with high-affinity nanostars

The natural phospholipid structure imparts exosomes with not only cargo protection, but rich sites for coordination with metal-organic frameworks (MOFs) to assemble functional nanocomplexes, such as signal amplifiers. Here, we exploit exosomes to tune MOF signal amplifiers (Exo-MOF) for ultrasensitive phenotyping of tumor-derived exosomes (tExo) based on self-driven coordination assembly and high-affinity nanostars. Exo-MOF leverages the specific coordination interaction between exosome and MOF that cages abundant redox molecules to assemble a super-redox signal amplifier. Moreover, the dispersed immuno-magnetic nanostars, which are assembled with antibodies on the surface of Au nanostars-coated magnetic nanoparticles, allow for rapid capturing of target tExo, addressing the limited mass transfer on electrode surface. Both Exo-MOF and high-affinity nanostars orchestrate the ultrahigh sensitivity (1 particle per 100 μL, higher than that no Exo-MOF by at least 10-fold), specificity and speed of the sensor in tExo detection. Such a sensitive strategy allows profiling tExo across seven cancer types, and revealing the distinct exosomal surface expression patterns. Further, the Exo-MOF sensor accurately distinguishes cancer patients from healthy individuals in a clinical cohort, and provides new opportunities for functional materials assembly and precision diagnostics.

Recent progress in functional metal-organic frameworks for bio-medical application

Metal-organic frameworks (MOFs) have a high specific surface area, adjustable pores and can be used to obtain functional porous materials with diverse and well-ordered structures through coordination and self-assembly, which has intrigued wide interest in a broad range of disciplines. In the arena of biomedical engineering, the functionalized modification of MOFs has produced drug carriers with excellent dispersion and functionalities such as target delivery and response release, with promising applications in bio-detection, disease therapy, tissue healing, and other areas. This review summarizes the present state of research on the functionalization of MOFs by physical binding or chemical cross-linking of small molecules, polymers, biomacromolecules, and hydrogels and evaluates the role and approach of MOFs functionalization in boosting the reactivity of materials. On this basis, research on the application of functionalized MOFs composites in biomedical engineering fields such as drug delivery, tissue repair, disease treatment, bio-detection and imaging is surveyed, and the development trend and application prospects of functionalized MOFs as an important new class of biomedical materials in the biomedical field are anticipated, which may provide some inspiration and reference for further development of MOF for bio-medical applications.

Light-Triggered Signal Enhancement Strategy Integrated with a CRISPR/Cas13a-Based Assay for Ultrasensitive and Specific miRNA Detection

The development of facile, accurate, and affordable assays for microRNAs (miRNAs) in early cancer is greatly desirable but encounters an obstacle due to low cellular abundance in biofuids. In this study, we present a novel approach called a light-triggered exponential amplification strategy coupled with a CRISPR/Cas13a-based diagnostic system (LEXPA-CRISPR), which directly transduces rare miRNA targets into photocontrolled signal enhancement response. This innovative platform leverages trans-cleavage of CRISPR/Cas13a, activated by the miRNA target, to cleave specific RNA fragments within the MB@PC-NAC assembly, thus releasing free PC-single-stranded DNA (PC-ssDNA) that is modified by a photocleavable linker (PC linker). UV irradiation is further employed toward the photoresponsive PC-ssDNA, resulting in instantaneous generation of oligo with a new 5' phosphate group (Pho-ssDNA). The Pho-ssDNA serves as a trigger for rolling circle amplification (RCA) reaction, which generates thousands of long ssDNA repeats of diverse lengths with a strong fluorescence signal. Through optimization, we achieved a detection limit of 1 fM for miR21 without the need for target amplification. Moreover, the programmable versatility of LEXPA-CRISPR is also demonstrated for miR17 determination only with simple modification of CRISPR RNA (crRNA) sequences. This proposed biosensor successfully monitored the levels of miR21 and miR17 in tumor cells, showing a satisfactory consistency with the standard qRT-PCR method. Conclusively, LEXPA-CRISPR represents a promising strategy for ultrasensitive miRNA detection. It combines the advantages of light-triggered signal amplification and robust collateral cleavage activity of Cas13a, making it an attractive tool for practical CRISPR-based diagnostics.

Preclinical Models and Technologies in Glioblastoma Research: Evolution, Current State, and Future Avenues

Glioblastoma is the most common malignant primary central nervous system tumor and one of the most debilitating cancers. The prognosis of patients with glioblastoma remains poor, and the management of this tumor, both in its primary and recurrent forms, remains suboptimal. Despite the tremendous efforts that are being put forward by the research community to discover novel efficacious therapeutic agents and modalities, no major paradigm shifts have been established in the field in the last decade. However, this does not mirror the abundance of relevant findings and discoveries made in preclinical glioblastoma research. Hence, developing and utilizing appropriate preclinical models that faithfully recapitulate the characteristics and behavior of human glioblastoma is of utmost importance. Herein, we offer a holistic picture of the evolution of preclinical models of glioblastoma. We further elaborate on the commonly used in vitro and vivo models, delving into their development, favorable characteristics, shortcomings, and areas of potential improvement, which aids researchers in designing future experiments and utilizing the most suitable models. Additionally, this review explores progress in the fields of humanized and immunotolerant mouse models, genetically engineered animal models, 3D in vitro models, and microfluidics and highlights promising avenues for the future of preclinical glioblastoma research.

Multifunctional dumbbell probes-based logic circuits: microRNAs logic detection and tumor cells identification

BACKGROUND

The powerful logic processing capability of DNA logic circuits over multiple input signals perfectly meets the demands of multi-biomarker-based clinical diagnostics. As important biomarkers for cancer diagnosis and treatment, the orthogonal differential expression of microRNAs (miRNAs) in different diseases and different cancer cells makes the precise logical detection of multiple miRNAs particularly critical.

RESULTS

Therefore, we constructed two fundamental "AND" and "OR" logic gates and one "AND-OR" logic gate on the basis of our proposed multifunctional dumbbell probes. These logic gates allowed for the logical profiling of multiple cancer-associated miRNAs. In addition, by making simple adjustments to the functional modules of multifunctional dumbbell probes, the three logic gates we proposed could be easily transformed without the use of sophisticated probe design. Remarkably, these logic gates, in particular the "AND-OR" logic gate, were able to compute several miRNAs simultaneously, demonstrating excellent cell identification capabilities.

SIGNIFICANCE

Overall, this work provided a new idea for accurately distinguishing multiple cell types and showed great application prospects.