Hydrogel-based hybridization chain reaction (HCR) for detection of urinary exosomal miRNAs as a diagnostic tool of prostate cancer

Current landscape of exosomal non-coding RNAs in prostate cancer: Modulators and biomarkers

Prostate cancer (PCa) has the highest frequency of diagnosis among solid tumors and ranks second as the primary cause of cancer-related deaths. Non-coding RNAs (ncRNAs), such as microRNAs, long non-coding RNAs and circular RNAs, frequently exhibit dysregulation and substantially impact the biological behavior of PCa. Compared with circulating ncRNAs, ncRNAs loaded into exosomes are more stable because of protection by the lipid bilayer. Furthermore, exosomal ncRNAs facilitate the intercellular transfer of molecules and information. Increasing evidence suggests that exosomal ncRNAs hold promising potential in the progression, diagnosis and prognosis of PCa. This review aims to discuss the functions of exosomal ncRNAs in PCa, evaluate their possible applications as clinical biomarkers and therapeutic targets, and provide a comprehensive overview of the ncRNAs regulatory network in PCa. We also identified ncRNAs that can be utilized as biomarkers for diagnosis, staging, grading and prognosis assessment in PCa. This review offers researchers a fresh perspective on the functions of exosomal ncRNAs in PCa and provides additional options for its diagnosis, progression monitoring, and prognostic prediction.

Nucleic Acid Amplification Circuit-Based Hydrogel (NACH) Assay for One-Step Detection of Metastatic Gastric Cancer-Derived Exosomal miRNA

Gastric cancer (GC) is recognized as the fifth most prevalent malignant tumor worldwide. It is characterized by diverse clinical symptoms, treatment responses, and prognoses. In GC prognosis, the promotion of epithelial-mesenchymal transition (EMT) fosters cancer cell invasion and metastasis, thereby triggering the dissemination of tumor cells. This study proposes a nucleic acid amplification circuit-based hydrogel (NACH) assay for identifying exosomal miRNA derived from metastatic GC. The NACH assay employs the rolling circle amplification method and targets miRNA-21, a tumor-related oncogene, and miRNA-99a, which promotes EMT. Specific amplification probes for each target are immobilized within the hydrogel, enabling a streamlined, one-step amplification reaction. The NACH assay exhibits a detection limit of 1 fm for miRNA-21 and miRNA-99a, thereby enabling rapid and highly sensitive on-site detection. Performance evaluation using exosomal miRNA extracted from cell culture media, mouse plasma, and human plasma revealed fluorescence intensity patterns similar to those obtained in qRT-PCR. Furthermore, deploying a custom-developed portable fluorometer for the NACH assay allows for diagnostic performance assessment and point-of-care testing using clinical samples from GC patients. These findings emphasize the potential of the NACH assay to be used as a robust tool for the genetic diagnosis of GC based on exosome detection.

Liquid biopsy: Comprehensive overview of circulating tumor DNA (Review)

Traditional tumor diagnosis methods rely on tissue biopsy, which can be invasive and unsuitable for long-term monitoring of tumor dynamics. The advent of liquid biopsy has notably improved the overall management of patients with cancer. Liquid biopsy techniques primarily involve detection of circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA). The present review focuses on ctDNA because of its significance in tumor diagnosis, monitoring and treatment. The use of ctDNA-based liquid biopsy offers several advantages, including non-invasive or minimally invasive collection methods, the ability to conduct repeated assessment and comprehensive insights into tumor biology. It serves crucial roles in disease management by facilitating screening of high-risk patients, dynamically monitoring therapeutic responses and diagnosis. Furthermore, ctDNA can be used to demonstrate pseudo-progression, monitor postoperative tumor status and guide adaptive treatment plans. The present study provides a comprehensive review of ctDNA, exploring its origins, metabolism, detection methods, clinical role and the current challenges associated with its application.

Fluorescein-switching-based lateral flow assay for the detection of microRNAs

Lateral flow assays (LFAs) are a cost-effective and rapid colorimetric technology that can be effectively used for nucleic acid tests (NATs) in various fields such as medical diagnostics and biotechnology. Given their importance, developing more diverse LFAs that operate through novel working mechanisms is essential for designing highly selective and sensitive NATs and providing insights for designing various practical point-of-care testing (POCT) systems. Herein we report a new type of lateral flow assay (LFA) based on fluorescein-switching, enabled by nucleic acid-templated photooxidation of reduced fluorescein by riboflavin tetraacetate (RFTA). The LFA design leverages the fact that a reduced form of fluorescein, which weakly binds to gold nanoparticle (GNP)-conjugated anti-fluorescein antibodies, is oxidized in the presence of target nucleic acids to yield its native state, which then strongly binds to the antibodies. The study involved designing and optimizing probe sequences to detect miR-6090 and miR-141, which are significant markers for prostate cancer. To minimize background signals of LFAs, sodium borohydride (NaBH4) was specifically introduced as a reducing agent, and detailed procedures were established. The developed LFA system accurately identified low fmol levels of target microRNAs with minimal false positives, all detectable with the naked eye, making the system a promising tool for point-of-care diagnostics.

Simultaneous Multi-miRNA Detection in Urinary Small Extracellular Vesicles Using Target-Triggered Locked Hairpin DNA-Functionalized Au Nanoprobes for Systemic Lupus Erythematosus Diagnosis

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by multiorgan involvement and complex clinical manifestations, leading to cumbersome diagnostic processes. MicroRNAs (miRNAs) in small extracellular vesicles (sEVs) have emerged as promising biomarkers for liquid biopsy. Herein, we constructed a simple multi-miRNA detection platform based on target-triggered locked hairpin DNA-functionalized Au nanoprobes (AuNP@LH) as a simple and noninvasive tool for the diagnosis and classification of SLE. The nanoprobes were prepared by modifying locked hairpin DNA designed for target miRNAs on gold nanoparticles. In the presence of target miRNAs, target-triggered hairpin assembly amplification was induced, and then fluorophore-labeled bolt DNA was released, resulting in a fluorescence signal responsive to miRNA concentration. Benefiting from the enzyme-free amplification strategy, the limits of detection (LOD) of three miRNA biomarkers for SLE were 19 pM for microRNA-146a, 66 pM for microRNA-29c, and 19 pM for microRNA-150. The proposed probes have been successfully applied to simultaneously detect multiple miRNAs in urinary sEVs from patients diagnosed with SLE and healthy controls, which exhibited good practicability in SLE diagnosis with the area under curve (AUC) of the receiver characteristic curve reaching 1.00. Furthermore, SLE patients with different disease severity can be differentiated with 81.2% accuracy. Predictably, with the advantages of low cost, rapidity, high sensitivity, and noninvasiveness, our multi-miRNA detection platform is a potential tool for multiple miRNA analysis and related clinical applications.

Efficient isolation of encoded microparticles in a degassed micromold for highly sensitive and multiplex immunoassay with signal amplification

Multiplex detection of low-abundance protein biomarkers in biofluids can contribute to diverse biomedical fields such as early diagnosis and precision medicine. However, conventional techniques such as digital ELISA, microarray, and hydrogel-based assay still face limitations in terms of efficient protein detection due to issues with multiplexing capability, sensitivity, or complicated assay procedures. In this study, we present the degassed micromold-based particle isolation technique for highly sensitive and multiplex immunoassay with enzymatic signal amplification. Using degassing treatment of nanoporous polydimethylsiloxane (PDMS) micromold, the encoded particles are isolated in the mold within 5 min absorbing trapped air bubbles into the mold by air suction capability. Through 10 min of signal amplification in the isolated spaces by fluorogenic substrate and horseradish peroxidase labeled in the particle, the assay signal is amplified with one order of magnitude compared to that of the standard hydrogel-based assay. Using the signal amplification assay, vascular endothelial growth factor (VEGF) and chorionic gonadotropin beta (CG beta), the preeclampsia-related protein biomarkers, are quantitatively detected with a limit of detection (LoD) of 249 fg/mL and 476 fg/mL in phosphate buffer saline. The multiplex immunoassay is conducted to validate negligible non-specific detection signals and robust recovery rates in the multiplex assay. Finally, the VEGF and CG beta in real urine samples are simultaneously and quantitatively detected by the developed assay. Given the high sensitivity, multiplexing capability, and process simplicity, the presented particle isolation-based signal amplification assay holds significant potential in biomedical and proteomic fields.

Unignored intracellular journey and biomedical applications of extracellular vesicles

The intracellular journey of extracellular vesicles (EVs) cannot be ignored in various biological pathological processes. In this review, the biogenesis, biological functions, uptake pathways, intracellular trafficking routes, and biomedical applications of EVs were highlighted. Endosomal escape is a unique mode of EVs release. When vesicles escape from endosomes, they avoid the fate of fusing with lysosomes and being degraded, thus having the opportunity to directly enter the cytoplasm or other organelles. This escape mechanism is crucial for EVs to deliver specific signals or substances. The intracellular trafficking of EVs after endosomal escape is a complex and significant biological process that involves the coordinated work of various cellular structures and molecules. Through the in-depth study of this process, the function and regulatory mechanism of EVs are fully understood, providing new dimensions for future biomedical diagnosis and treatment.

In Situ Intracellular Autocatalytic Hairpin Assembly of the Y-Shaped DNA Nanostructure for miR-155 Sensing and Gene Silencing

miR-155 is a class of cancer markers closely related to cancer metastasis and invasion. Combining in situ detection with gene silencing not only helps to analyze the information on the abundance and spatial location of microRNA expression in the cell but also synergizes the therapy. In this work, we prepared HD@CM vesicles with three hairpin DNAs by using MCF-7 cell membranes. The hairpin DNAs can be triggered by endogenous miR-155, which opens the autocatalytic molecular circuit (ACHA) and obtains Y-shaped DNA nanostructures. This nanostructure not only detects endogenous miR-155 with high sensitivity for in situ imaging but also enables gene regulation of intracellular survivin mRNA. The levels of miR-155 in MDA-MB-231, MCF-7, Hela, and HEK-293T cells are found to be 7703, 3978, 1696, and 1229 copies/cell, respectively, as detected by HD@CMs. The fluorescence produced by HD@CM after coincubation with different cells is found to be proportional to the intracellular miR-155 content by confocal imaging. In addition, the gene regulatory function of the Y-shaped DNA structure resulted in significant inhibition of survivin protein expression and apoptosis rates of up to 83%. We look forward to the future application of our HD@CM platform for the precise diagnosis and programmable treatment of clinical cancers.

Visual Detection of LPS at the Femtomolar Level Based on Click Chemistry-Induced Gold Nanoparticles Electrokinetic Accumulation

Lipopolysaccharide (LPS) presents a significant threat to human health. Herein, a novel method for detecting LPS was developed by coupling hybridization chain reaction (HCR), gold nanoparticles (AuNPs) agglutination (AA) triggered by a Cu(I)-catalyzed azide-alkyne cycloaddition click chemistry (CuAAC), and electrokinetic accumulation (EA) in a microfluidic chip, termed the HCR-AA-EA method. Thereinto, the LPS-binding aptamer (LBA) was coupled with the AuNP-coated Fe3O4 nanoparticle, which was connected with the polymer of H1 capped on CuO (H1-CuO) and H2-CuO. Upon LPS recognition by LBA, the polymers of H1- and H2-CuO were released into the solution, creating a "one LPS-multiple CuO" effect. Under ascorbic acid reduction, CuAAC was initiated between the alkyne and azide groups on the AuNPs' surface; then, the product was observed visually in the microchannel by EA. Finally, LPS was quantified by the integrated density of AuNP aggregates. The limit of detections were 29.9 and 127.2 fM for water samples and serum samples, respectively. The levels of LPS in the injections and serum samples by our method had a good correlation with those from the limulus amebocyte lysate test (r = 0.99), indicating high accuracy. Remarkably, to popularize our method, a low-cost, wall-power-free portable device was developed, enabling point-of-care testing.

Exosomes as Powerful Biomarkers in Cancer: Recent Advances in Isolation and Detection Techniques

Exosomes, small extracellular vesicles derived from cells, are known to carry important bioactive molecules such as proteins, nucleic acids, and lipids. These bioactive components play crucial roles in cell signaling, immune response, and tumor metastasis, making exosomes potential diagnostic biomarkers for various diseases. However, current methods for detecting tumor exosomes face scientific challenges including low sensitivity, poor specificity, complicated procedures, and high costs. It is essential to surmount these obstacles to enhance the precision and dependability of diagnostics that rely on exosomes. Merging DNA signal amplification techniques with the signal boosting capabilities of nanomaterials presents an encouraging strategy to overcome these constraints and improve exosome detection. This article highlights the use of DNA signal amplification technology and nanomaterials' signal enhancement effect to improve the detection of exosomes. This review seeks to offer valuable perspectives for the enhancement of amplification methods applied in practical cancer diagnosis and prognosis by providing an overview of how these novel technologies are utilized in exosome-based diagnostic procedures.

Hybridization chain reaction assisted terahertz metamaterial biosensor for highly sensitive detection of microRNAs

MicroRNA (miRNA) is closely related to the occurrence and development of cancer. Accurate determination of the miRNA concentration is of great significance for early cancer diagnosis. However, due to the short sequence and low concentration of miRNA, it is still a challenge to achieve low-concentration detection. In this work, we proposed a method for the highly sensitive detection of miRNA-21 using a terahertz (THz) metamaterial sensor combined with a Hybridization chain reaction (HCR). First, a capture hairpin probe was combined with gold nanoparticles (AuNPs), which were then modified to the surface of the sensor for specific binding of miRNA-21. Then the signal amplification technique of HCR is used to amplify the trace amount of miRNA, and the super-long dendritic DNA macromolecules are formed on the surface of the sensor. This changes the dielectric environment of the sensor surface, and the resonance frequency of the sensor is shifted. The method has good specificity and sensitivity, and the concentration of miRNA-21 in the range of 100 aM to 10 nM shows excellent linear relationship with frequency shift. Most importantly, it paves the way for low-cost, easy-to-operate and marker-free miRNA detection.

Label-free and highly sensitive detection of microRNA from cancer cells via target-induced cascade amplification generation of lighting-up RNA aptamers

The abnormal expression levels of miRNAs have been proven to be highly related to the generation of various diseases and are also closely associated with the stages and types of disease development. The novel RNA aptamers-based homogenous fluorescent methods were simple, with low background signal and high signal-to-noise ratio, but lacked effective signal amplification technology to achieve sensitive detection of trace miRNA markers. There is an urgent need for combining effective nucleic acid amplification technology with RNA aptamer to achieve highly sensitive and accurate detection of miRNA. For this purpose, a new DNA multi-arm nanostructure-based dual rolling circle transcription machinery for the generation of lighting-up MG RNA aptamers is constructed for label-free and highly sensitive sensing of miRNA-21. In this system, the target miRNA-21 induces a structural transformation of the DNA multi-arm nanostructure probe to recycle miRNA-21 and trigger two independent rolling circle transcription reactions to generate two long RNAs, which can partially hybridize with each other to generate large amounts of complete MG RNA aptamers. These RNA aptamers can associate with organic MG dye to produce significantly enhanced fluorescence signals to accomplish ultrasensitive miRNA-21 detection down to 0.9 fM. In addition, this method exhibits high selectivity to distinguish miRNA-21 even with single nucleotide mismatch, and also has potential application capability to monitor different expression levels of miRNA-21 from different cancer cells. The effective collaboration between MG RNA aptamer and rolling circle transcription reaction makes this fluorescent method show the significant advantages of low background signal, high signal-to-noise ratio and high detection sensitivity. It has great potential to be a promising means to achieve label-free and highly sensitive monitoring of other trace biological markers via a simple change of target sequence.

Biomaterials for Drug Delivery and Human Applications

Biomaterials embody a groundbreaking paradigm shift in the field of drug delivery and human applications. Their versatility and adaptability have not only enriched therapeutic outcomes but also significantly reduced the burden of adverse effects. This work serves as a comprehensive overview of biomaterials, with a particular emphasis on their pivotal role in drug delivery, classifying them in terms of their biobased, biodegradable, and biocompatible nature, and highlighting their characteristics and advantages. The examination also delves into the extensive array of applications for biomaterials in drug delivery, encompassing diverse medical fields such as cancer therapy, cardiovascular diseases, neurological disorders, and vaccination. This work also explores the actual challenges within this domain, including potential toxicity and the complexity of manufacturing processes. These challenges emphasize the necessity for thorough research and the continuous development of regulatory frameworks. The second aim of this review is to navigate through the compelling terrain of recent advances and prospects in biomaterials, envisioning a healthcare landscape where they empower precise, targeted, and personalized drug delivery. The potential for biomaterials to transform healthcare is staggering, as they promise treatments tailored to individual patient needs, offering hope for improved therapeutic efficacy, fewer side effects, and a brighter future for medical practice.

Smartphone-Based Fluorescent Profiling of Quaternary MicroRNAs in Urine for Rapid Diagnosis of Urological Cancers Using a Multiplexed Isothermal Exponential Amplification Reaction

Urological cancers such as bladder or prostate cancer represent one of the most malignant tumors that accounts for an extremely high mortality. However, conventionally standard diagnostics for urological cancers are hardly available in low-resource settings. We developed herein a hand-held fluorescent imaging platform by integrating a multiplexed isothermal exponential amplification reaction (EXPAR) with a microgel-enriched methodology for sensitive profiling of quaternary microRNAs (miRNAs) in urine and quick diagnosis of urological cancers at the early stage. The target miRNA mixtures in the urine underwent four parallel EXPARs without cross-reactivity, followed by surface concentration and hybridization by the encoded polyacrylamide microgels. This mix-and-read strategy allowed for one-pot analysis of several key miRNAs simultaneously and provided 5-fold enhancement in fluorescent detection sensitivities compared to the individual EXPAR-based assays. Four urinary miRNAs (let-7a, miRNA-155, -223, and -143) could be quantitatively determined in a wide linear range from 50 fM to 30 nM, with the limits of detection at femtomolar levels. Using a smartphone-based imaging microreader, healthy and cancerous cohorts with prostate, bladder, and renal cell cancers could be discriminated in 30 min with the accuracy >83% using linear discriminant analysis. The developed detection platform has proven to be a portable, noninvasive, and useful complement to the toolbox for miRNA-based liquid biopsies, which holds immense potential and advantage for regular and large-scale applications in early cancer diagnosis.

Highly Flexible Deep-Learning-Based Automatic Analysis for Graphically Encoded Hydrogel Microparticles

Graphically encoded hydrogel microparticle (HMP)-based bioassay is a diagnostic tool characterized by exceptional multiplex detectability and robust sensitivity and specificity. Specifically, deep learning enables highly fast and accurate analyses of HMPs with diverse graphical codes. However, previous related studies have found the use of plain particles as data to be disadvantageous for accurate analyses of HMPs loaded with functional nanomaterials. Furthermore, the manual data annotation method used in existing approaches is highly labor-intensive and time-consuming. In this study, we present an efficient deep-learning-based analysis of encoded HMPs with diverse graphical codes and functional nanomaterials, utilizing the auto-annotation and synthetic data mixing methods for model training. The auto-annotation enhanced the throughput of dataset preparation up to 0.11 s/image. Using synthetic data mixing, a mean average precision of 0.88 was achieved in the analysis of encoded HMPs with magnetic nanoparticles, representing an approximately twofold improvement over the standard method. To evaluate the practical applicability of the proposed automatic analysis strategy, a single-image analysis was performed after the triplex immunoassay for the preeclampsia-related protein biomarkers. Finally, we accomplished a processing throughput of 0.353 s per sample for analyzing the result image.

Catalytic probes based on aggregation-induced emission-active Au nanoclusters for visualizing MicroRNA in living cells and in vivo

Highly sensitive monitoring of cancer-related miRNAs is of great significance for tumor diagnosis. Herein, catalytic probes based on DNA-functionalized Au nanoclusters (AuNCs) were prepared in this work. The aggregation-induced emission-active Au nanoclusters showed an interesting phenomenon of aggregation induced emission (AIE) affected by the aggregation state. Leveraging this property, the AIE-active AuNCs were used to develop catalytic turn-on probes for detecting in vivo cancer-related miRNA based on a hybridization chain reaction (HCR). The target miRNA triggered the HCR and induced aggregation of AIE-active AuNCs, leading to a highly luminescent signal. The catalytic approach demonstrated a remarkable selectivity and a low detection limit in comparison to noncatalytic sensing signals. In addition, the excellent delivery the ability of MnO₂ carrier made it possible to use the probes for intracellular imaging and in vivo imaging. Effective in situ visualization of miR-21 was achieved not only in living cells but also in tumors in living animals. This approach potentially offers a novel method for obtaining information for tumor diagnosis via highly sensitive cancer-related miRNA imaging in vivo.

Bifunctional Y-shaped probe combined with dual amplification for colorimetric sensing and molecular logic operation of two miRNAs

The abnormal expression of miRNA is closely related to various human diseases. In particular, the sensitivity detection of miRNA expression level is of great significance for the early diagnosis and prognosis of cancer. In this paper, we designed a Y-shaped DNA probe, using miRNA-21 and miRNA-141 as the dual input signals of AND logic gate. By combining with EXO III assisted target recycle and DNA hybridization chain reaction (HCR), we have realized dual signal amplification for detection of two miRNAs. In short, the Y-shaped DNA probe consists of two parts: the miRNA target binding region and the HCR initiator. When the two miRNAs are present at the same time, the target binding region specifically recognizes the target to generate two circulators, and then the HCR initiator is released. The EXO III specific cleavage two circulator, and release the target again which achieves the first step of signal amplification. After that, HCR was started by the split initiator generated in the first stage of continuous cycle, and the second step of signal amplification was realized. Thanks to the sensitive color change of gold nanoparticles in response to salt, we achieved ultra-high sensitivity for visual detection of miRNA-21 and miRNA-141. Under optimal conditions, the detection limit of both miRNA is 3 pM and the linear range is 10 pM to 0.4 nM. The method we designed could be applied in early detection and diagnosis of cancer.

Enzymatic reaction modulated DNA assembly on graphitic carbon nitride nanosheets for sensitive fluorescence detection of acetylcholinesterase activity and inhibition

A novel fluorescent strategy has been developed by using an enzymatic reaction modulated DNA assembly on graphitic carbon nitride nanosheets (CNNS) for the detection of acetylcholinesterase (AChE) activity and its inhibitors. The two-dimensional and ultrathin-layer CNNS-material was successfully synthesized through a chemical oxidation and ultrasound exfoliation method. Because of its excellent adsorption selectivity to ssDNA over dsDNA and superior quenching ability toward the fluorophore labels, CNNS were employed to construct a sensitive fluorescence sensing platform for the detection of AChE activity and inhibition. The detection was based on enzymatic reaction modulated DNA assembly on CNNS, which involved the specific AChE-catalyzed reaction-mediated DNA/Hg²⁺ conformational change and subsequent signal transduction and amplification via hybridization chain reaction (HCR). Under the excitation at 485 nm, the fluorescence signal from 500 to 650 nm (λ_max = 518 nm) of the developed sensing system was gradually increased with increasing concentration of AChE. The quantitative determination range of AChE is from 0.02 to 1 mU/mL and the detection limit was 0.006 mU/mL. The developed strategy was successfully applied to the assay of AChE in human serum samples, and can also be used to effectively screen AChE inhibitors, showing great promise providing a robust and effective platform for AChE-related diagnosis, drug screening, and therapy.

Systematic Analysis of Tissue-Derived and Biofluid Extracellular Vesicle miRNAs Associated with Prostate Cancer

Extracellular vesicles (EVs) are emerging as biomarker candidates for early detection of prostate cancer. Studies compare EV-microRNA (miRNA) expression in individuals with prostate cancer (PCa) with cancer-free samples for diagnostic purposes. The aim of this study is to review miRNA signatures to investigate the overlap between miRNAs enriched in PCa tissue and miRNAs enriched in EVs isolated from subjects with PCa biofluids (i.e., urine, serum, and plasma). Signatures dysregulated in EVs from PCa biofluids and tissue are potentially associated with the primary tumor site and might be more indicative of PCa at an early stage. A systematic review of EV-derived miRNAs and a reanalysis of PCa tissue miRNA sequencing data for comparison is presented. Articles in the literature are screened for validated miRNA dysregulation in PCa and compared with TCGA primary PCa tumor data using DESeq2. This resulted in 190 dysregulated miRNAs being identified. Thirty-one eligible studies are identified, indicating 39 dysregulated EV-derived miRNAs. The top ten markers identified as significantly dysregulated in the PCa tissue dataset TCGA (e.g., miR-30b-3p, miR-210-3p, miR-126-3p, and miR-196a-5p) have a significant expression change in EVs with the same directionality in one or several statistically significant results. This analysis highlights several less frequently studied miRNAs in PCa literature.

Wheel drive-based DNA sensing system for highly specific and rapid one-step detection of MiRNAs at the attomolar level

With the use of DNA as building blocks, a variety of microRNA amplification-based sensing systems have been developed. Nevertheless, ultrasensitive, selective and rapid detection of microRNAs with a high signal-to-background ratio and point mutation discrimination ability remains a challenge. Herein, we propose a novel wheel drive-based DNA sensing system (NWDS) based on a self-assembled, self-quenched nanoprobe (SQP) to conduct highly specific and ultrasensitive one-step measurement of microRNAs. In this work, a signalling recognition DNA hairpin (DH) sequence with a self-complementary stem domain of 14 base pairs was used, which contained three functional regions, namely a recognition region for the target miRNA-21, a sticky region with 9 complementary nucleotides to the 3'terminus of a DNA wheel (DW) and a region for the hybridization with a quenching DNA primer (DP). The SQP was ingeniously self-assembled at room temperature by the DH and DP, which was capable of eliminating unwanted background signals. MiRNA-21 was employed as a target model to specifically activate the SQP, leading to specific hybridization between the HP and DW. With the assistance of a polymerase, an SQP-based wheel driving took place to induce hybridization/polymerization displacement cycles, initiating target recycling and DP displacement. As a result, a large amount of the newly formed hybrid SQP/DW accumulated to generate a substantially enhanced fluorescence signal. In this way, the newly proposed NWDS exhibits ultrasensitivity with a detection limit of 5.62 aM across a wide linear dynamic response range up to 200 nM, excellent selectivity with the capability to discriminate homologous miRNAs and one-base, two-base and three-base mismatched sequences, and an outstanding analytical performance in complex systems. In addition, the significant simultaneous advantages of one-step operation, rapid detection within 15 min and a high signal-to-background ratio of 26 offer a unique opportunity to promote the early diagnosis of cancer-related diseases and molecular biological analysis.

Dynamic Role of Exosome microRNAs in Cancer Cell Signaling and Their Emerging Role as Noninvasive Biomarkers

Exosomes are extracellular vesicles that originate from endosomes and are released by all cells irrespective of their origin or type. They play an important role in cell communication and can act in an autocrine, endocrine, or paracrine fashion. They are 40-150 nm in diameter and have a similar composition to the cell of origin. An exosome released by a particular cell is unique since it carries information about the state of the cell in pathological conditions such as cancer. miRNAs carried by cancer-derived exosomes play a multifaceted role by taking part in cell proliferation, invasion, metastasis, epithelial-mesenchymal transition, angiogenesis, apoptosis, and immune evasion. Depending on the type of miRNA that it carries as its cargo, it can render cells chemo- or radiosensitive or resistant and can also act as a tumor suppressor. Since the composition of exosomes is affected by the cellular state, stress, and changes in the environment, they can be used as diagnostic or prognostic biomarkers. Their unique ability to cross biological barriers makes them an excellent choice as vehicles for drug delivery. Because of their easy availability and stability, they can be used to replace cancer biopsies, which are invasive and expensive. Exosomes can also be used to follow the progression of diseases and monitor treatment strategies. A better understanding of the roles and functions of exosomal miRNA can be used to develop noninvasive, innovative, and novel treatments for cancer.

Compute-and-Release Logic-Gated DNA Cascade Circuit for Accurate Cancer Cell Imaging

Accurate identification of cancer cells is an essential prerequisite for cancer diagnosis and subsequent effective curative interventions. The logic-gate-assisted cancer imaging system that allows a comparison of expression levels between biomarkers, rather than just reading biomarkers as inputs, returns a more comprehensive logical output, improving its accuracy for cell identification. To fulfill this key criterion, we develop a compute-and-release logic-gated double-amplified DNA cascade circuit. This novel system, CAR-CHA-HCR, consists of a compute-and-release (CAR) logic gate, a double-amplified DNA cascade circuit (termed CHA-HCR), and a MnO₂ nanocarrier. CAR-CHA-HCR, a novel adaptive logic system, is designed to logically output the fluorescence signals after computing the expression levels of intracellular miR-21 and miR-892b. Only when miR-21 is present and its expression level is above the threshold C_miR-21 > C_miR-892b, the CAR-CHA-HCR circuit performs a compute-and-release operation on free miR-21, thereby outputting enhanced fluorescence signals to accurately image positive cells. It is capable of comparing the relative concentrations of two biomarkers while sensing them, thus allowing accurate identification of positive cancer cells, even in mixed cell populations. Such an intelligent system provides an avenue for highly accurate cancer imaging and is potentially envisioned to perform more complex tasks in biomedical studies.

Ratiometric electrochemical OR gate assay for NSCLC-derived exosomes

Non-small cell lung cancer (NSCLC) is the most common pathological type of LC and ranks as the leading cause of cancer deaths. Circulating exosomes have emerged as a valuable biomarker for the diagnosis of NSCLC, while the performance of current electrochemical assays for exosome detection is constrained by unsatisfactory sensitivity and specificity. Here we integrated a ratiometric biosensor with an OR logic gate to form an assay for surface protein profiling of exosomes from clinical serum samples. By using the specific aptamers for recognition of clinically validated biomarkers (EpCAM and CEA), the assay enabled ultrasensitive detection of trace levels of NSCLC-derived exosomes in complex serum samples (15.1 particles μL^-1 within a linear range of 10²-10⁸ particles μL^-1). The assay outperformed the analysis of six serum biomarkers for the accurate diagnosis, staging, and prognosis of NSCLC, displaying a diagnostic sensitivity of 93.3% even at an early stage (Stage I). The assay provides an advanced tool for exosome quantification and facilitates exosome-based liquid biopsies for cancer management in clinics.

Colorimetric aptasensor based on spherical nucleic acid-induced hybridization chain reaction for sensitive detection of exosomes

Exosomes are one of the most promising biomarkers for tumor diagnosis and prognosis. Therefore, the development of convenient and sensitive exosome sensing strategies is of great significance. Herein, we integrated aptamer-based spherical nucleic acids (SNAs) and hybridization chain reaction (HCR) into a colorimetric aptasensor platform and applied it to the detection of exosomes. In this design, the CD63-specific aptamer pre-immobilized on the microplate was used to capture target exosomes, while the SNAs conjugated with nucleolin-specific aptamer and trigger probe H1 were designed for amplifying signal. In the presence of target exosomes, the SNAs can be attached to the microplate by the bridge effect of exosomes, resulting in the trigger of HCR. This process is accompanied by the formation of abundant G-quadruplex/hemin DNAzyme, enabling the visual quantitative analysis of exosomes. Featured with the dual amplification of SNAs and HCR, the proposed aptasensor achieved a considerable detection limit of 50 particles/μL. The practicability of this method was further verified by testing the different clinical samples. Given the ability of the aptasensor to visually detect exosomes in scenarios lacking instruments and resources, we believe that the aptasensor can be serve as a potential on-site test for liquid biopsy.

Development of a hybridization chain reaction-powered lab-on-fiber device for ultrafast point-of-care testing of circulating tuor DNA in whole blood

Circulating tumor DNA (ctDNA) demonstrates great promise in the guidance of prognostication, diagnosis, and surveillance of cancers, which highlights the need for rapid and sensitive point-of-care testing (POCT) technologies. Hybridization chain reaction (HCR)-based optical biosensors provide excellent solutions due to their prominent features. However, the requirement of a sophisticated and expensive optical readout device, relatively long detection time, and heating hold back their scalability and clinical applications. Here, an innovative HCR-powered lab-on-fiber device (HCR-LOFD) was developed for rapid on-site detection of ctDNA with high sensitivity, specificity, and reproducibility. A LOFD with a compact all-fiber optical structure was constructed for the fluorescence detection of the HCR system. Combining HCR, fluorescence energy resonant transfer, and the evanescent wave fluorescence principle, HCR-LOFD achieved the quantitative detection of KRAS G12D, the 12th amino acid from glycine (Gly) mutated aspartate (Asp) and the most common mutation of KARS, in 5 min at room temperature based on end-point detection mode or real-time fluorescence detection mode. This new assay platform was also successfully applied for the direct detection of KRAS G12D in whole blood with simple dilution. The application of HCR-LOFD not only greatly simplifies the complexity of optical readout devices and improves their scalability but also potentially serves as a sample-to-answer solution for the detection of biomarkers in limited medical resource regions.

Highly Effective Detection of Exosomal miRNAs in Plasma Using Liposome-Mediated Transfection CRISPR/Cas13a

Exosomal miRNAs play a critical role in cancer biology and could be potential biomarkers for cancer diagnosis. However, due to the low abundance of miRNAs in the exosomes, recognizing and detecting disease-associated exosomal miRNAs in an easy-to-operate way remain a challenge. Herein, we used a liposome-mediated membrane fusion strategy (MFS) to transfect CRISPR/Cas13a into exosomes, termed MFS-CRISPR, directly measuring exosomal miRNAs in plasma. Using the MFS-CRISPR platform for detection of the exosomal miR-21, we achieve a linear range spanning four orders of magnitude (10⁴-10⁸ particles/mL) and the method is able to detect the exosomal miR-21 in as low as 1.2 × 10³ particles/mL. The liposome-mediated MFS could confine fluorescent signals in fused vesicles, which can be used for exosome heterogeneity analysis. Moreover, MFS-CRISPR assay was evaluated by measuring clinical samples, and the difference of miR-21 expression of breast cancer patients and healthy donors was significant. Because of high sensitivity and simplicity, the proposed method could have promising clinical potential for cancer diagnosis and treatment monitoring.

Self-assembly of DNA-hyperbranched aggregates catalyzed by a dual-targets recognition probe for miRNAs SERS detection in single cells

MicroRNAs (miRNAs) are very important for the early diagnosis and prognosis of tumors. In this work, we achieved the simultaneous detection of microRNA-155 (miR-155) and microRNA-21 (miR-21) with a dual target recognition probe (DRP) based on the nonlinear hybridization chain reaction (HCR). The multi-branched DNA products, three-dimensional multi-hotspot DNA dendrimers (3DmhD) were used in the amplification of the target miRNAs signal. The DRP is constructed with a core of gold nanocages (AuNCs), modified by nucleic acid probes and labeled with Raman signaling molecules ROX and Cy3. Experiments demonstrated that DRP could activate the multi-branched DNA reaction and generate 3DmhD in the presence of miR-155 and miR-21, which can achieve effective amplification of miR-21 and miR-155. When Surface Enhanced Raman Scattering (SERS) analysis was performed on 3DmhD, the multi-hot spot effect of 3DmhD significantly enhanced the signals of ROX and Cy3, allowing ultra-sensitive detection of miR-21 and miR-155 in vitro. To our delight, DRP also exhibited sensitive specificity and significant signal amplification for intracellular miRNAs. These results revealed that DRP has the potential to screen tumor cells by analyzing the expression levels of intracellular miRNAs.

Recent strategies for electrochemical sensing detection of miRNAs in lung cancer

MicroRNAs (miRNAs) associated with lung cancer are diversifying. MiR-21, Let-7, and miR-141 are common diagnostic targets. Some new lung cancer miRNAs, such as miR-25, miR-145, and miR-126, have received increasing attention. Although various techniques are available for the analysis of lung cancer miRNAs, electrochemistry has been recognized for its high sensitivity, low cost, and rapid response. However, how to realize the signal amplification is one of the most important contents in the design of electrochemical biosensors. Herein, we mainly introduce the amplification strategy based on enzyme-free amplification and signal conversion, including non-linear HCR, catalytic hairpin assembly (CHA), electrochemiluminescence (ECL), and Faraday cage. Furthermore, new progress has emerged in the fields of nanomaterials, low oxidation potential, and simultaneous detection of multiple targets. Finally, we summarize some new challenges that electrochemical techniques may encounter in the future, such as improving single-base discrimination ability, shortening electrochemical detection time, and providing real body fluid samples assay.

The Role of Urinary miRNAs in the Diagnosis, Management and Follow- Up of Prostatic Cancer

Diagnosis and management of prostatic cancer (PCa) cases mainly rely on levels of prostatic- specific antigen (PSA) levels. In the majority of cases, rising of PCa is usually responsible for elevated PSA. However, a wide variety of prostatic abnormalities, such as benign prostatic hyperplasia and infection or inflammation of the prostatic glands, may also impact prostate levels. Due to the low specificity and sensitivity of the PSA test, elevated PSA levels can lead to unnecessary prostate biopsies or surgical interventions, constituting this diagnostic modality a controversial screening test. Therefore, the discovery of new non-invasive biomarkers, such as urinary miRNAs, could shed light on the optimal management and follow-up of patients with prostatic lesions. This study aims to evaluate the utility of urinary miRNAs as a new PCa prognostic biomarker, discovering its current limitations and proposing methods to overwhelm current challenges.

Recent Advances in Exosomal miRNA Biosensing for Liquid Biopsy

As a noninvasive detection technique, liquid biopsy plays a valuable role in cancer diagnosis, disease monitoring, and prognostic assessment. In liquid biopsies, exosomes are considered among the potential biomarkers because they are important bioinformation carriers for intercellular communication. Exosomes transport miRNAs and, thus, play an important role in the regulation of cell growth and function; therefore, detection of cancer cell-derived exosomal miRNAs (exo-miRNAs) gives effective information in liquid biopsy. The development of sensitive, convenient, and reliable exo-miRNA assays will provide new perspectives for medical diagnosis. This review presents different designs and detection strategies of recent exo-miRNA assays in terms of signal transduction and amplification, as well as signal detection. In addition, this review outlines the current attempts at bioassay methods in liquid biopsies. Lastly, the challenges and prospects of exosome bioassays are also considered.

Urinary microRNAs and Their Significance in Prostate Cancer Diagnosis: A 5-Year Update

Simple Summary

Current diagnostics of prostate cancer often show unsatisfactory results, leading to delayed detection or overtreatment. Urinary microRNAs are a class of promising non-invasive biomarkers. Although many studies have been conducted on this topic in the last five years, there is little agreement on the data obtained. This review aims to discuss new knowledge but also focuses on technical aspects affecting urinary miRNA analysis.

Abstract

Current routine screening methods for the diagnosis of prostate cancer (PCa) have significantly increased early detection of the disease but often show unsatisfactory analytical parameters. A class of promising markers represents urinary microRNAs (miRNAs). In the last five years, there has been an extensive increase in the number of studies on this topic. Thus, this review aims to update knowledge and point out technical aspects affecting urinary miRNA analysis. The review of relevant literature was carried out by searching the PubMed database for the keywords: microRNA, miRNA, urine, urinary, prostate cancer, and diagnosis. Papers discussed in this review were retrieved using PubMed, and the search strategy was as follows: (urine OR urinary) WITH (microRNA OR miRNA) AND prostate cancer. The search was limited to the last 5 years, January 2017 to December 2021. Based on the defined search strategy, 31 original publications corresponding to the research topic were identified, read and reviewed to present the latest findings and to assess possible translation of urinary miRNAs into clinical practice. Reviews or older publications were read and cited if they valuably extended the context and contributed to a better understanding. Urinary miRNAs are potentially valuable markers for the diagnosis of prostate cancer. Despite promising results, there is still a need for independent validation of exploratory data, which follows a strict widely accepted methodology taking into account the shortcomings and factors influencing the analysis.

Biological Features of Extracellular Vesicles and Challenges

Extracellular vesicles (EVs) are vesicles with a lipid bilayer membrane on the outside, which are widely found in various body fluids and contain biological macromolecules such as DNA, RNA, lipids and proteins on the inside. EVs were once thought to be vesicles for the removal of waste materials, but are now known to be involved in a variety of pathophysiological processes in many diseases. This study examines the advantage of EVs and the challenges associated with their application. A more rational use of the advantageous properties of EVs such as composition specificity, specific targeting, circulatory stability, active penetration of biological barriers, high efficient drug delivery vehicles and anticancer vaccines, oxidative phosphorylation activity and enzymatic activity, and the resolution of shortcomings such as isolation and purification methods, storage conditions and pharmacokinetics and biodistribution patterns during drug delivery will facilitate the clinical application of EVs.

Highly accelerated isothermal nucleic acid amplifications by butanol dehydration: simple, more efficient, and ultrasensitive

Enzyme-free isothermal amplification reactions for nucleic acid analysis usually take several hours to obtain sufficient detection sensitivity, which limits their practical applications. Herein, we report a butanol dehydration-based method to greatly improve both the efficiency and the sensitivity of nucleic acid detections by three types of enzyme-free isothermal amplification reactions. The reaction time has been shortened from 3 h to 5-20 min with higher sensitivities. Especially in the DNAzyme-based amplification, the detection limit can be lowered over 16 000-fold to 3 × 10^-17 mol L^-1 in 2 h compared to the normal 3 h-reaction. We demonstrate that the high amplification efficiencies are attributed to the greatly accelerated reaction rates in the extremely concentrated reaction solutions caused by the butanol dehydration. This approach enhances the potential of applications of isothermal amplification reactions in clinical rapid tests, nanostructure synthesis, etc. and is promising to expand to other types of chemical reactions.

Quantitative and Multiplex Detection of Extracellular Vesicle-Derived MicroRNA via Rolling Circle Amplification within Encoded Hydrogel Microparticles

Extracellular vesicle-derived microRNA (EV-miRNA) represent a promising cancer biomarker for disease diagnosis and monitoring. However, existing techniques to detect EV-miRNA rely on complex, bias-prone strategies, and preprocessing steps, making absolute quantification highly challenging. This work demonstrates the development and application of a method for quantitative and multiplex detection of EV-miRNA, via rolling circle amplification within encoded hydrogel particles. By a one-pot extracellular vesicle lysis and microRNA capture step, the bias and losses associated with standard RNA extraction techniques is avoided. The system offers a large dynamic range (3 orders of magnitude), ease of multiplexing, and a limit of detection down to 2.3 zmol (46 × 10-18 m), demonstrating its utility in clinical applications based on liquid biopsy tests. Furthermore, orthogonal measurements of EV concentrations coupled with the direct, absolute quantification of miRNA in biological samples results in quantitative measurements of miRNA copy numbers per volume sample, and per extracellular vesicle.

miRNA sensing hydrogels capable of self-signal amplification for early diagnosis of Alzheimer's disease

Alzheimer's disease (AD), one of the leading senile disorders in the world, causes severe memory loss and cognitive impairment. To date, there is no clear cure for AD. However, early diagnosis and monitoring can help mitigate the effects of this disease. In this study, we reported a platform for diagnosing early-stage AD using microRNAs (miRNAs) in the blood as biomarkers. First, we selected an appropriate target miRNA (miR-574-5p) using AD model mice (4-month-old 5XFAD mice) and developed a hydrogel-based sensor that enabled high-sensitivity detection of the target miRNA. This hydrogel contained catalytic hairpin assembly (CHA) reaction-based probes, leading to fluorescence signal amplification without enzymes and temperature changes, at room temperature. This sensor exhibited high sensitivity and selectivity, as evidenced by its picomolar-level detection limit (limit of detection: 1.29 pM). Additionally, this sensor was evaluated using the plasma of AD patients and non-AD control to validate its clinical applicability. Finally, to use this sensor as a point-of-care-testing (POCT) diagnostic system, a portable fluorometer was developed and verified for feasibility of application.

Sensitive fluorescent detection of exosomal microRNA based on enzymes-assisted dual-signal amplification

The analysis of microRNAs (miRNAs) in exosomes offers significant information for a rapid and non-invasive diagnosis of cancer. However, the clinical utility of miRNAs as biomarkers is often hampered by their low abundance in exosomes. Herein, we develop a dual-signal amplification biosensor for the sensitive detection of exosomal miRNA-21 (miR-21). In the presence of a cognate target, it hybridizes with a biotin-modified capture probe (Cp) to form a DNA-RNA heteroduplex that serves as a substrate for duplex-specific nuclease (DSN). With the assistance of DSN, the Cps are enzymatically hydrolyzed and numerous DNA catalysts are released, leading to the first signal amplification. After magnetic isolation, the DNA catalyst remaining in the supernatant triggers a strand displacement reaction based on the nicking-assisted reactant recycling strategy, without depleting the reactants, to implement the second signal amplification. Using this dual-signal amplification concept, our biosensor achieves a limit of detection of miR-21 of 0.34 fM, with a linear range of 0.5-100 fM. The receiver operating characteristic curve generated during clinical sample analysis indicates that the exosomal miR-21 outperforms serum carcinoembryonic antigen in discriminating between patients with gastric cancer (GC) and patients with precancerous (PC) lesions (area under the curve: 0.89 versus 0.74, n = 40). Moreover, the proposed biosensor exhibits an 83.9% accuracy in classifying patients with GC or PC lesions and healthy donors using a confusion matrix. Furthermore, patients with GC with or without metastases are discriminated using the proposed biosensor. Our technology may expand the applications of DNA-based biosensor-enabled cancer diagnostic tools.

Single-Molecule Detection of Nucleic Acids via Liposome Signal Amplification in Mass Spectrometry

A single-molecule detection method was developed for nucleic acids based on mass spectrometry counting single liposome particles. Before the appearance of symptoms, a negligible amount of nucleic acids and biomarkers for the clinical diagnosis of the disease were already present. However, it is difficult to detect extremely low concentrations of nucleic acids using the current methods. Hence, the establishment of an ultra-sensitive nucleic acid detection technique is urgently needed. Herein, magnetic beads were used to capture target nucleic acids, and liposome particles were employed as mass tags for single-particle measurements. Liposomes were released from magnetic beads via photocatalytic cleavage. Hence, one DNA molecule corresponded to one liposome particle, which could be counted using mass spectrometric measurement. The ultrasensitive detection of DNA (10^-18 M) was achieved using this method.

Nanomaterials-Based Urinary Extracellular Vesicles Isolation and Detection for Non-invasive Auxiliary Diagnosis of Prostate Cancer

Extracellular vesicles (EVs) are natural nanoparticles secreted by cells in the body and released into the extracellular environment. They are associated with various physiological or pathological processes, and considered as carriers in intercellular information transmission, so that EVs can be used as an important marker of liquid biopsy for disease diagnosis and prognosis. EVs are widely present in various body fluids, among which, urine is easy to obtain in large amount through non-invasive methods and has a small dynamic range of proteins, so it is a good object for studying EVs. However, most of the current isolation and detection of EVs still use traditional methods, which are of low purity, time consuming, and poor efficiency; therefore, more efficient and highly selective techniques are urgently needed. Recently, inspired by the nanoscale of EVs, platforms based on nanomaterials have been innovatively explored for isolation and detection of EVs from body fluids. These newly developed nanotechnologies, with higher selectivity and sensitivity, greatly improve the precision of isolation target EVs from urine. This review focuses on the nanomaterials used in isolation and detection of urinary EVs, discusses the advantages and disadvantages between traditional methods and nanomaterials-based platforms, and presents urinary EV-derived biomarkers for prostate cancer (PCa) diagnosis. We aim to provide a reference for researchers who want to carry out studies about nanomaterial-based platforms to identify urinary EVs, and we hope to summarize the biomarkers in downstream analysis of urinary EVs for auxiliary diagnosis of PCa disease in detail.

A colorimetric aptasensor based on a hemin/EpCAM aptamer DNAzyme for sensitive exosome detection

Exosomes are considered as potential biomarkers that can reflect information from their parent cell-associated cancer microenvironment.

Recent Progress in Nanomaterials Modified Electrochemical Biosensors for the Detection of MicroRNA

MicroRNAs (miRNAs) are important non-coding, single-stranded RNAs possessing crucial regulating roles in human body. Therefore, miRNAs have received extensive attention from various disciplines as the aberrant expression of miRNAs are tightly related to different types of diseases. Furthermore, the exceptional stability of miRNAs has presented them as biomarker with high specificity and sensitivity. However, small size, high sequence similarity, low abundance of miRNAs impose difficulty in their detection. Hence, it is of utmost importance to develop accurate and sensitive method for miRNA biosensing. Electrochemical biosensors have been demonstrated as promising solution for miRNA detection as they are highly sensitive, facile, and low-cost with ease of miniaturization. The incorporation of nanomaterials to electrochemical biosensor offers excellent prospects for converting biological recognition events to electronic signal for the development of biosensing platform with desired sensing properties due to their unique properties. This review introduces the signal amplification strategies employed in miRNA electrochemical biosensor and presents the feasibility of different strategies. The recent advances in nanomaterial-based electrochemical biosensor for the detection of miRNA were also discussed and summarized based on different types of miRNAs, opening new approaches in biological analysis and early disease diagnosis. Lastly, the challenges and future prospects are discussed.

Exosomes as Intercellular Messengers in Hypertension

People living with hypertension have a higher risk of developing heart diseases, and hypertension remains a top cause of mortality. In hypertension, some detrimental changes occur in the arterial wall, which include physiological and biochemical changes. Furthermore, this disease is characterized by turbulent blood flow, increased fluid shear stress, remodeling of the blood vessels, and endothelial dysfunction. As a complex disease, hypertension is thought to be caused by an array of factors, its etiology consisting of both environmental and genetic factors. The Mosaic Theory of hypertension states that many factors, including genetics, environment, adaptive, neural, mechanical, and hormonal perturbations are intertwined, leading to increases in blood pressure. Long-term efforts by several investigators have provided invaluable insight into the physiological mechanisms responsible for the pathogenesis of hypertension, and these include increased activity of the sympathetic nervous system, overactivation of the renin-angiotensin-aldosterone system (RAAS), dysfunction of the vascular endothelium, impaired platelet function, thrombogenesis, vascular smooth muscle and cardiac hypertrophy, and altered angiogenesis. Exosomes are extracellular vesicles released by all cells and carry nucleic acids, proteins, lipids, and metabolites into the extracellular environment. They play a role in intercellular communication and are involved in the pathophysiology of diseases. Since the discovery of exosomes in the 1980s, numerous studies have been carried out to understand the biogenesis, composition, and function of exosomes. In this review, we will discuss the role of exosomes as intercellular messengers in hypertension.