The involvement of exosomes in the diagnosis and treatment of pancreatic cancer

Advances of machine learning-assisted small extracellular vesicles detection strategy

Detection of extracellular vesicles (EVs), particularly small EVs (sEVs), is of great significance in exploring their physiological characteristics and clinical applications. The heterogeneity of sEVs plays a crucial role in distinguishing different types of cells and diseases. Machine learning, with its exceptional data processing capabilities, offers a solution to overcome the limitations of conventional detection methods for accurately classifying sEV subtypes and sources. Principal component analysis, linear discriminant analysis, partial least squares discriminant analysis, XGBoost, support vector machine, k-nearest neighbor, and deep learning, along with some combined methods such as principal component-linear discriminant analysis, have been successfully applied in the detection and identification of sEVs. This review focuses on machine learning-assisted detection strategies for cell identification and disease prediction via sEVs, and summarizes the integration of these strategies with surface-enhanced Raman scattering, electrochemistry, inductively coupled plasma mass spectrometry and fluorescence. The performance of different machine learning-based detection strategies is compared, and the advantages and limitations of various machine learning models are also evaluated. Finally, we discuss the merits and limitations of the current approaches and briefly outline the perspective of potential research directions in the field of sEV analysis based on machine learning.

Role of macrophages and their exosomes in orthopedic diseases

Exosomes are vesicles with a lipid bilayer structure that carry various active substances, such as proteins, DNA, non-coding RNA, and nucleic acids; these participate in the immune response, tissue formation, and cell communication. Owing to their low immunogenicity, exosomes play a key role in regulating the skeletal immune environment. Macrophages are important immune cells that swallow various cellular and tissue fragments. M1-like and M2-like macrophages differentiate to play pro-inflammatory, anti-inflammatory, and repair roles following stimulation. In recent years, the increase in the population base and the aging of the population have led to a gradual rise in orthopedic diseases, placing a heavy burden on the social medical system and making it urgent to find effective solutions. Macrophages and their exosomes have been demonstrated to be closely associated with the pathogenesis and prognosis of orthopedic diseases. An in-depth understanding of their mechanisms of action and the interaction between them will be helpful for the future clinical treatment of orthopedic diseases. This review focuses on the mechanisms of action, diagnosis, and treatment of orthopedic diseases involving macrophages and their exosomes, including fracture healing, diabetic bone damage, osteosarcoma, and rheumatoid arthritis. In addition, we discuss the prospects and major challenges faced by macrophages and their exosomes in clinical practice.

Research progress of exosomes in the angiogenesis of digestive system tumour

Malignant tumours of the digestive system cover a wide range of diseases that affect the health of people to a large extent. Angiogenesis is indispensable in the development, and metastasis of tumours, mainly in two ways: occupation or formation. Vessels can provide nutrients, oxygen, and growth factors for tumours to encourage growth and metastasis, so cancer progression depends on simultaneous angiogenesis. Recently, exosomes have been proven to participate in the angiogenesis of tumours. They influence angiogenesis by binding to tyrosine kinase receptors (VEGFR)-1, VEGFR-2, and VEGFR-3 with different affinities, regulating Yap-VEGF pathway, Akt pathway or other signaling pathway. Additionally, exosomes are potential therapeutic vectors that can deliver many types of cargoes to different cells. In this review, we summarize the roles of exosomes in the angiogenesis of digestive system tumours and highlight the clinical application prospects, directly used as targers or delivery vehicles, in antiangiogenic therapy.

Corosolic acid enhances oxidative stress-induced apoptosis and senescence in pancreatic cancer cells by inhibiting the JAK2/STAT3 pathway

BACKGROUND

Pancreatic cancer (PC) is a fatal human malignancy with a poor prognosis. Corosolic acid (CRA) is a triterpenoid, has been reported to have inhibitory effects on tumor growth. However, the role of CRA on PC has not been explored. Here, we aimed to uncover the molecular mechanisms of CRA in PC progression.

METHODS

Cell viability, lactate dehydrogenase (LDH) release, cell apoptosis and senescence were detected by cell counting kit-8 (CCK-8), LDH, flow cytometry and senescence associated-β-galactosidase (SA-β-gal) assay. Levels of relevant proteins and oxidative stress (OS) markers were evaluated by Western blot and enzyme-linked immunosorbent assay (ELISA). A xenograft tumor model was established to explore the in vivo effects of CRA on PC.

RESULTS

We found that CRA inhibited PC cell viability and promoted LDH release in a dose-dependent manner, but had no significant effect on human normal pancreatic ductal epithelial cells HPDE6C7. CRA increased OS-induced cell apoptosis and senescence in HAPC and SW1990 cells. And CRA decreased the levels of anti-apoptotic protein Bcl-2, and elevated the expression of pro-apoptotic protein Bax and senescence-associated proteins P21 and P53. Besides, CRA decreased tumor growth in xenograft models. Furthermore, CRA inactivated the Janus kinase-2 (JAK2)/Signal Transducer and Activator of Transcription 3 (STAT3) signaling pathway in HAPC and SW1990 cells. Functional experiments demonstrated that activation of the JAK2/STAT3 pathway by the JAK2 activator coumermycin A1 (C-A1) or the STAT3 activator colivelin (col) reduced the contribution effect of OS, apoptosis and senescence by CRA.

CONCLUSION

Taken together, our findings indicated that CRA exerted anti-cancer effects in PC by inhibiting the JAK2/STAT3 pathway.

Expression of miR-425-5p in Pancreatic Carcinoma and Its Correlation with Tumor Immune Microenvironment

Background: Pancreatic carcinoma (PC) is a global health threat with a high death rate. miRNAs are implicated in tumor initiation and progression. This study explored the expression of miR-425-5p in PC patients and its correlation with tumor immune microenvironment (TIME).Method: miR-425-5p expression in cancer tissues and adjacent non-tumor tissues of PC patients was examined by RT-qPCR. The levels of immune cells and cytokines were measured by flow cytometry and ELISA. The correlation of miR-425-5p with TNM stage and TIME was assessed by Spearman method. The death of PC patients was recorded through 36-month follow-ups. The prognosis of patients was assessed by Kaplan-Meier curves.Results: miR-425-5p expression was upregulated in PC tissues and elevated with increasing TNM stage. miR-425-5p expression was positively correlated with TNM stage. The PC tissues had decreased levels of CD3+, CD4+, CD8+, and natural killer (NK) cells, CD4+/CD8+ ratio, IL-2, and INF-γ, but increased levels of Tregs, IL-4, IL-10, and TGF-β. miR-425-5p level in cancer tissues was positively correlated with Tregs/IL-10/TGF-β, but negatively related to CD3+/CD4+/CD8+/NK cells and IL-2/INF-γ. Moreover, high miR-425-5p expression predicted a poor prognosis in PC patients.Conclusion: miR-425-5p is upregulated in PC patients and is prominently associated with the TIME, and high miR-425-5p predicts a poor prognosis in PC patients.

Diagnosis and prognosis of pancreatic cancer with immunoglobulin heavy constant delta blood marker

BACKGROUND

Pancreatic cancer (PC) is highly malignant and difficult to detect, while few blood markers are currently available for diagnosing PC.

METHODS

We obtained differential expression genes (DEGs) from GEO (gene expression omnibus) database and assessed by quantitative real-time polymerase chain reaction (qRT-PCR), receiver operating characteristic (ROC), univariate and multifactorial regression analysis, and survival analysis in our clinic center. Through the TCGA (the cancer genome atlas) database, we analyzed functional enrichment, different risk groups with survival analysis, immunological features, and the risk score established by the Cox regression model and constructed a nomogram.

RESULT

Immunoglobulin heavy constant delta (IGHD) was remarkably upregulated in peripheral blood from PC patients, and IGHD was a potential independent biomarker for PC diagnosis (ROC sensitivity, 76.0%; specificity, 74.2%; area under the curve (AUC) = 0.817; univariate logistic regression analysis: odds ratio (OR) 1.488; 95% confidence interval (CI) 1.182-1.872; P < 0.001; multiple logistic: OR 2.097; 95% CI 1.276-3.389, P = 0.003). In addition, the IGHD expression was remarkably reduced after resectioning the primary tumor. High IGHD expression indicated higher lymphocyte infiltration and increased activities of immunological pathways in PC patients. KRAS and SMAD were observed with a prominent difference among top mutated genes between the two groups. The risk score predicted reliable clinical prognosis and drug responses. Furthermore, a nomogram with the risk score and clinical characteristics was constructed, showing a better predictive performance.

CONCLUSION

IGHD is a valuable PC diagnosis, prognosis, and therapeutic response marker.

Exosome and lipid metabolism-related genes in pancreatic adenocarcinoma: a prognosis analysis

OBJECTIVE

The purpose of the study was to investigate the role of exosome and lipid metabolism-related genes (EALMRGs) mRNA levels in the diagnosis and prognosis of Pancreatic Adenocarcinoma (PAAD).

METHODS

The mRNA expression pattern of PAAD and pan-cancers with prognostic data were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. EALMRGs were acquired from GeneCards and MSigDB database after merging and deduplication. Prognostic EALMRGs were screened through univariate COX regression analysis, and a prognostic model was constructed based on these genes by least absolute shrinkage and selection operator (LASSO) regression. The prognostic value of EALMRGs was then validated in pan-cancer data. The time characteristics ROC curve analysis was performed to evaluate the effectiveness of the prognostic genes.

RESULTS

We identified 5 hub genes (ABCB1, CAP1, EGFR, PPARG, SNCA) according to high and low-risk groups of prognoses. The risk formula was verified in three other cohort of pancreatic cancer patients and was explored in pan-cancer data. Additionally, T cell and dendritic cell infiltration was significantly increased in low-risk group. The expression of the 5 hub genes was also identified in single-cell sequencing data of pancreatic cancer with pivotal pathways. Additionally, functional enrichment analysis based on pancreatic cancer data in pancreatic cancer showed that protein serine/threonine kinase activity, focal adhesion, actin binding, cell-substrate junction, organic acid transport, and regulation of transporter activity were significant related to the expression of genes in EALMRGs.

CONCLUSIONS

Our risk formula shows potential prognostic value in multiple cancers and manifest pivotal alterations in immune infiltration and biological pathway in pancreatic cancer.

Engineered Exosomes as Theranostic Platforms for Cancer Treatment

Tremendous progress in nanotechnology and nanomedicine has made a significant positive effect on cancer treatment by integrating multicomponents into a single multifunctional nanosized delivery system for combinatorial therapies. Although numerous nanocarriers developed so far have achieved excellent therapeutic performance in mouse models via elegant integration of chemotherapy, photothermal therapy, photodynamic therapy, sonodynamic therapy, and immunotherapy, their synthetic origin may still cause systemic toxicity, immunogenicity, and preferential detection or elimination by the immune system. Exosomes, endogenous nanosized particles secreted by multiple biological cells, could be absorbed by recipient cells to facilitate intercellular communication and content delivery. Therefore, exosomes have emerged as novel cargo delivery tools and attracted considerable attention for cancer diagnosis and treatment due to their innate stability, biological compatibility, and biomembrane penetration capacity. Exosome-related properties and functions have been well-documented; however, there are few reviews, to our knowledge, with a focus on the combination of exosomes and nanotechnology for the development of exosome-based theranostic platforms. To make a timely review on this hot subject of research, we summarize the basic information, isolation and functionalization methodologies, diagnostic and therapeutic potential of exosomes in various cancers with an emphasis on the description of exosome-related nanomedicine for cancer theranostics. The existing appealing challenges and outlook in exosome clinical translation are finally introduced. Advanced biotechnology and nanotechnology will definitely not only promote the integration of intrinsic advantages of natural nanosized exosomes with traditional synthetic nanomaterials for modulated precise cancer treatment but also contribute to the clinical translations of exosome-based nanomedicine as theranostic nanoplatforms.

Analysis of MicroRNA Signature Differentially Expressed in Pancreatic Islet Cells Treated with Pancreatic Cancer-Derived Exosomes

Since the majority of patients with pancreatic cancer (PC) develop insulin resistance and/or diabetes mellitus (DM) prior to PC diagnosis, PC-induced diabetes mellitus (PC-DM) has been a focus for a potential platform for PC detection. In previous studies, the PC-derived exosomes were shown to contain the mediators of PC-DM. In the present study, the response of normal pancreatic islet cells to the PC-derived exosomes was investigated to determine the potential biomarkers for PC-DM, and consequently, for PC. Specifically, changes in microRNA (miRNA) expression were evaluated. The miRNA specimens were prepared from the untreated islet cells as well as the islet cells treated with the PC-derived exosomes (from 50 patients) and the healthy-derived exosomes (from 50 individuals). The specimens were subjected to next-generation sequencing and bioinformatic analysis to determine the differentially expressed miRNAs (DEmiRNAs) only in the specimens treated with the PC-derived exosomes. Consequently, 24 candidate miRNA markers, including IRS1-modulating miRNAs such as hsa-miR-144-5p, hsa-miR-3148, and hsa-miR-3133, were proposed. The proposed miRNAs showed relevance to DM and/or insulin resistance in a literature review and pathway analysis, indicating a potential association with PC-DM. Due to the novel approach used in this study, additional evidence from future studies could corroborate the value of the miRNA markers discovered.

Towards artificial intelligence-enabled extracellular vesicle precision drug delivery

Extracellular Vesicles (EVs), particularly exosomes, recently exploded into nanomedicine as an emerging drug delivery approach due to their superior biocompatibility, circulating stability, and bioavailability in vivo. However, EV heterogeneity makes molecular targeting precision a critical challenge. Deciphering key molecular drivers for controlling EV tissue targeting specificity is in great need. Artificial intelligence (AI) brings powerful prediction ability for guiding the rational design of engineered EVs in precision control for drug delivery. This review focuses on cutting-edge nano-delivery via integrating large-scale EV data with AI to develop AI-directed EV therapies and illuminate the clinical translation potential. We briefly review the current status of EVs in drug delivery, including the current frontier, limitations, and considerations to advance the field. Subsequently, we detail the future of AI in drug delivery and its impact on precision EV delivery. Our review discusses the current universal challenge of standardization and critical considerations when using AI combined with EVs for precision drug delivery. Finally, we will conclude this review with a perspective on future clinical translation led by a combined effort of AI and EV research.

Identification of a New m6A Regulator-Related Methylation Signature for Predicting the Prognosis and Immune Microenvironment of Patients with Pancreatic Cancer

Pancreatic cancer (PC) is a malignant tumor of the digestive system that has a bad prognosis. N6-methyladenosine (m6A) is involved in a wide variety of biological activities due to the fact that it is the most common form of mRNA modification in mammals. Numerous research has accumulated evidence suggesting that a malfunction in the regulation of m6A RNA modification is associated with various illnesses, including cancers. However, its implications in PC remain poorly characterized. The methylation data, level 3 RNA sequencing data, and clinical information of PC patients were all retrieved from the TCGA datasets. Genes associated with m6A RNA methylation were compiled from the existing body of research and made available for download from the m6Avar database. The LASSO Cox regression method was used to construct a 4-gene methylation signature, which was then used to classify all PC patients included in the TCGA dataset into either a low- or high-risk group. In this study, based on the set criteria of |cor| > 0.4 and p value < 0.05. A total of 3507 gene methylation were identified to be regulated by m6A regulators. Based on the univariate Cox regression analysis and identified 3507 gene methylation, 858 gene methylation was significantly associated with the patient's prognosis. The multivariate Cox regression analysis identified four gene methylation (PCSK6, HSP90AA1, TPM3, and TTLL6) to construct a prognosis model. Survival assays indicated that the patients in the high-risk group tend to have a worse prognosis. ROC curves showed that our prognosis signature had a good prediction ability on patient survival. Immune assays suggested a different immune infiltration pattern in patients with high- and low-risk scores. Moreover, we found that two immune-related genes, CTLA4 and TIGIT, were downregulated in high-risk patients. We generated a unique methylation signature that is related to m6A regulators and is capable of accurately predicting the prognosis for patients with PC. The findings might prove useful for therapeutic customization and the process of making medical decisions.

Tumor-suppressive miR-29c binds to MAPK1 inhibiting the ERK/MAPK pathway in pancreatic cancer

INTRODUCTION

GEO- and TCGA-based data analysis suggested the differential expression of miR-29c in pancreatic cancer. However, limited data are available on the downstream mechanistic actions of miR-29c, which may fuel the in vitro and in vivo studies of pancreatic cancer.

METHODS

The downstream target gene of miR-29c and the downstream ERK/MAPK pathway involved in pancreatic cancer were predicted by bioinformatics tools. Next, the expression of miR-29c and MAPK1 was determined in pancreatic cancer tissues and cells. After ectopic expression and depletion experiments in pancreatic cancer cells, oncogenic phenotypes of pancreatic cancer cells were tested by MTS assay, Transwell assay, and flow cytometry. Effects of miR-29c/MAPK1 on tumorigenic ability in vivo were evaluated in pancreatic cancer xenografts in nude mice.

RESULTS

Through differential analysis, five pancreatic cancer-related miRNAs (hsa-miR-29c, hsa-miR-107, hsa-miR-324-3p, hsa-miR-375, and hsa-miR-210) were screened out, among which miR-29c was selected as the key miRNA related to prognosis of pancreatic cancer patients. miR-29c could target and inhibit MAPK1 to suppress the activation of ERK/MAPK pathway. miR-29c was downregulated in pancreatic cancer, and its high expression was related to the good prognosis of pancreatic cancer patients. Both in vitro and in vivo experiments demonstrated that restoration of miR-29c inhibited oncogenic phenotypes of pancreatic cancer cells, as well as repressed tumorigenic ability of pancreatic cancer cells in nude mice.

CONCLUSIONS

Taken together, we unveil a novel miR-29c/MAPK1/ERK/MAPK axis that suppresses pancreatic cancer both in vitro and in vivo.

The hidden potential of glycomarkers: Glycosylation studies in the service of cancer diagnosis and treatment

Changes in the glycosylation process appear early in carcinogenesis and evolve with the growth and spread of cancer. The correlation of the characteristic glycosylation signature with the tumor stage and the appropriate therapy choice is an important issue in translational medicine. Oncologists also pay attention to extracellular vesicles as reservoirs of new cancer glycomarkers that can be potent for cancer diagnosis/prognosis. In this review, we recall glycomarkers used in oncology and show their new glycoforms of improved clinical relevance. We summarize current knowledge on the biological functions of glycoepitopes in cancer-derived extracellular vesicles and their potential use in clinical practice. Is glycomics a future of cancer diagnosis? It may be, but in combination with other omics analyses than alone.

Biochemistry of exosomes and their theranostic potential in human diseases

Exosomes are classified as special extracellular vesicles in the eukaryotic system having diameters ranging from 30 to 120 nm. These vesicles carry various endogenous molecules including DNA, mRNA, microRNA, circular RNA, and proteins, crucial for numerous metabolic reactions and can be proposed as therapeutic or diagnostic targets for several disorders. The donor exosomes release their content to recipient cells and further establish the significant intercellular communication showing biological effects by triggering environmental alterations. Exosomes derived from mesenchymal and dendritic cells have demonstrated their therapeutic potential against organ injury. Yet, various intricacies are involved in exosomal transport and its inclusion in cancer and other disease pathogenesis needs to be explored. The exosomes represent profound potential as diagnostic biomarkers and therapeutic carriers in various pathophysiological conditions such as neurodegenerative diseases, chronic cancers, infectious diseases, female reproductive diseases and cardiovascular diseases. In the current study, we demonstrate the advancements in the implication of exosomes as one of the irrefutable prognostic biological targets in human health and diseases.

The Detection of Exosomal PD-L1 in Peripheral Blood

Peripheral blood is a source for liquid biopsy, which can meet the requirements of pretreatment disease typing to determine precise targeted therapy and monitoring of posttreatment minimal residual disease monitoring. Compared with ctDNA and CTC, exosomes have a higher concentration, good biostability, biocompatibility, low immunogenicity, and low toxicity in peripheral blood. Tumors generally secrete a large amounts of exosomes, which have potential pathophysiological roles in tumor progression. With the continuous improvement of liquid biopsy technology, many researchers have found that exosomes are the key for tumor PD-L1 to exert its role, which may be the mechanism that leads to PD-L1 and/or PD-1 inhibitor therapy resistance. Namely, tumor-derived exosomes may mediate systemic immunosuppression against PD-1 or PD-L1 inhibitor therapy, endogenous tumor cell-derived exosomal PD-L1, and tumor microenvironment-derived exosomes. Induction of PD-L1 by exosomes may be a crucial mechanisms of exosome-mediated antitumor immune tolerance. This article reviews the relationship between the detection of peripheral blood exosomal PD-L1 and tumor progression and the mechanism of exosomal PD-L1 in tumor immunotherapy.

Status quo of Extracellular Vesicle isolation and detection methods for clinical utility

Extracellular vesicles (EVs) are nano-sized particles that hold tremendous potential in the clinical space, as their biomolecular profiles hold a key to non-invasive liquid biopsy for cancer diagnosis and prognosis. EVs are present in most bodily fluids, hence are easily obtainable from patients, advantageous to that of traditional, invasive tissue biopsies and imaging techniques. However, there are certain constraints that hinder clinical use of EVs. The translation of EV biomarkers from "bench-to-bedside" is encumbered by the methods of EV isolation and subsequent biomarker detection currently implemented in laboratories. Although current isolation and detection methods are effective, they lack practicality, with their requirement for high bodily fluid volumes, low equipment availability, slow turnaround times and high costs. The high demand for techniques that overcome these limitations has resulted in significant advancements in nanotechnological devices. These devices are designed to integrate EV isolation and biomarker detection into a one-step method of direct EV detection from bodily fluids. This provides promise for the acceleration of EVs into current clinical standards. This review highlights the importance of EVs as cancer biomarkers, the methodological obstacles currently faced in clinical studies and how novel nanodevices could advance clinical translation.

Exosomes and their roles in the chemoresistance of pancreatic cancer

Pancreatic cancer (PC) remains one of the most lethal human malignancies worldwide. Due to the insidious onset and the rapid progression, most patients with PC are diagnosed at an advanced stage rendering them inoperable. Despite the development of multiple promising chemotherapeutic agents as recommended first-line treatment for PC, the therapeutic efficacy is largely limited by unwanted drug resistance. Recent studies have identified exosomes as essential mediators of intercellular communications during the occurrence of drug resistance. Understanding the underlying molecular mechanisms and complex signaling pathways of exosome-mediated drug resistance will contribute to the improvement of the design of new oncologic therapy regimens. This review focuses on the intrinsic connections between the chemoresistance of PC cells and exosomes in the tumor microenvironment (TME).

A novel risk score model based on four angiogenesis long non-coding RNAs for prognosis evaluation of pancreatic adenocarcinoma

BACKGROUND

Long non-coding RNAs (lncRNAs) have been reported to play significant roles in tumour angiogenesis which prominently facilitates pancreatic adenocarcinoma (PAAD) progression.

METHODS

The clinical PAAD data were obtained from TCGA database and clinical specimens of 122 PAAD patients. The Molecular Signatures Database v4.0 was used to identify angiogenesis-related long non-coding RNAs (ARLNRs). Survival-related ARLNRs (sARLNRs) were further validated by univariate and multivariate COX regression analyses. The expressions of CASC8, AC015660.1, Z97832.2 and PAN3-AS1 in PAAD cell lines and tissues were examined by qPCR. The correlations between sARLNRs (CASC8 and AC015660.1) and clinicopathological characteristics of the 122 PAAD patients were analyzed by the chi-square test and Fisher's exact probability method.

RESULTS

590 lncRNAs were identified as ARLNRs, of which four sARLNRs were further used to establish an angiogenesis-related risk score model (ARRS), by which patients in the low-risk group have better survival probabilities than those in the high-risk group. The expression levels of CASC8 and AC015660.1 were significantly higher in PAAD cell lines and tumor tissues especially in patients with advanced grades and T-stages, while Z97832.2 and PAN3-AS1 were inverse. In addition, the higher expression of CASC8 and AC015660.1 prominently associated with the larger tumour size, and the more advanced grade and T-stage. However, the relevance between the sARLNRs (CASC8 and AC015660.1) expression and lymph node metastasis status was not significant.

CONCLUSIONS

In the study, we illuminate the clinical significance, angiogenesis relevance and prognosis-predictive value of four sARLNRs for PAAD. The results build a bridge between sARLNRs and tumour vascularization, and also establish a reliable and accurate risk scoring model for PAAD antiangiogenic strategy.

Exosomal DNAJB11 promotes the development of pancreatic cancer by modulating the EGFR/MAPK pathway

Pancreatic ductal adenocarcinoma (PDAC) is a malignant tumor with invasive and metastatic characteristics and poor prognosis. Intracellular protein homeostasis is associated with invasion and metastasis of pancreatic cancer, but the specific molecular mechanism remains unclear. Our previous studies have revealed that DNAJB11, a key protein in protein homeostasis, is secreted by exosomes in the supernatant of dissociated pancreatic cancer cells with high metastasis. The results from transcriptome sequencing and co-immunoprecipitation (Co-IP)-based liquid chromatography with tandem mass spectrometry (LC–MS/MS) showed that depletion of DNAJB11 levels could increase HSPA5 expression and induce endoplasmic reticulum stress through the PRKR-like endoplasmic reticulum kinase signaling pathway in pancreatic cancer cells. Furthermore, exosomal DNAJB11 promoted cell development of PC cells in vitro and in vivo. In addition, exosomal DNAJB11 could regulate the expression of EGFR and activate the downstream MAPK signaling pathway. Clinical blood samples were collected to evaluate the potential of exosome DNAJB11 as a diagnostic biomarker and therapeutic target for the treatment of pancreatic cancer. This study could provide a new theoretical basis and potential molecular targets for the treatment of pancreatic cancer.

Artificial intelligence in pancreatic cancer

Pancreatic cancer is the deadliest disease, with a five-year overall survival rate of just 11%. The pancreatic cancer patients diagnosed with early screening have a median overall survival of nearly ten years, compared with 1.5 years for those not diagnosed with early screening. Therefore, early diagnosis and early treatment of pancreatic cancer are particularly critical. However, as a rare disease, the general screening cost of pancreatic cancer is high, the accuracy of existing tumor markers is not enough, and the efficacy of treatment methods is not exact. In terms of early diagnosis, artificial intelligence technology can quickly locate high-risk groups through medical images, pathological examination, biomarkers, and other aspects, then screening pancreatic cancer lesions early. At the same time, the artificial intelligence algorithm can also be used to predict the survival time, recurrence risk, metastasis, and therapy response which could affect the prognosis. In addition, artificial intelligence is widely used in pancreatic cancer health records, estimating medical imaging parameters, developing computer-aided diagnosis systems, etc. Advances in AI applications for pancreatic cancer will require a concerted effort among clinicians, basic scientists, statisticians, and engineers. Although it has some limitations, it will play an essential role in overcoming pancreatic cancer in the foreseeable future due to its mighty computing power.

KRAS as a Key Oncogene in the Clinical Precision Diagnosis and Treatment of Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant tumors, with a 5-year survival rate of less than 10%. At present, the comprehensive treatment based on surgery, radiotherapy and chemotherapy has encountered a bottleneck, and targeted immunotherapy turns to be the direction of future development. About 90% of PDAC patients have KRAS mutations, and KRAS has been widely used in the diagnosis, treatment, and prognosis of PDAC in recent years. With the development of liquid biopsy and gene testing, KRAS is expected to become a new biomarker to assist the stratification and prognosis of PDAC patients. An increasing number of small molecule inhibitors acting on the KRAS pathway are being developed and put into the clinic, providing more options for PDAC patients.

Oxidative stress state inhibits exosome secretion of hPDLCs through a specific mechanism mediated by PRMT1

BACKGROUND AND OBJECTIVES

Periodontitis, the most common chronic inflammation characterized by persistent alveolar bone resorption in the periodontitis, affects almost half of the adult population worldwide. Oxidative stress is one of the pathophysiological mechanisms underlying periodontitis, which affects the occurrence and development of periodontitis. Exosomes are increasingly recognized as vehicles of intercellular communication and are closely related to periodontitis. However, the effects of oxidative stress on exosome secretion and the specific mechanisms remain elusive in human periodontal ligament cells (hPDLCs). The relationship between exosome secretion and the osteogenic differentiation of hPDLCs also needs to be investigated.

METHODS

Isolated PDLSCs were identified using flow cytometry. Osteogenesis was measured using alizarin red staining and ALP staining. Expression of exosomal markers and PRMT1 was analyzed using western blot. Immunofluorescence was used to measure exosome uptake and the expression of EEA1.

RESULTS

The secretion capacity of exosomes was markedly suppressed under oxidative stress. Protein arginine methyltransferase 1 (PRMT1) has been strongly associated with both oxidative stress and inflammation, and PRMT1 was significantly upregulated under oxidative stress conditions. Lentivirus-mediated overexpression of PRMT1 caused a significant reduction in the secretion of exosomes, but multivesicular bodies (MVBs) containing a large number of intraluminal vesicles (ILVs) were increased. Rab11a and Rab27a expression, which mediate MVBs fusion with cell membranes, decreased, although this phenomenon was restored after knocking down PRMT1 expression under oxidative stress.

CONCLUSIONS

These results indicated that PRMT1 mediated a decrease in exosome secretion of hPDLCs. The decrease in Rab11a and Rab27a leads to a large accumulation of MVBs in cells and is one of the main reasons for impaired exosome secretion. The decrease in osteogenic differentiation of hPDLCs caused by H₂ O₂ may originate in part from the inhibition of exosome secretion.

Alternating exosomes and their mimetics as an emergent strategy for targeted cancer therapy

Exosomes, a subtype of the class of extracellular vesicles and nano-sized particles, have a specific membrane structure that makes them an alternative proposition to combat with cancer through slight modification. As constituents of all most all the primary body fluids, exosomes establish the status of intercellular communication. Exosomes have specific proteins/mRNAs and miRNAs which serve as biomarkers, imparting a prognostic tool in clinical and disease pathologies. They have efficient intrinsic targeting potential and efficacy. Engineered exosomes are employed to deliver therapeutic cargos to the targeted tumor cell or the recipient. Exosomes from cancer cells bring about changes in fibroblast via TGFβ/Smad pathway, augmenting the tumor growth. These extracellular vesicles are multidimensional in terms of the functions that they perform. We herein discuss the uptake and biogenesis of exosomes, their role in various facets of cancer studies, cell-to-cell communication and modification for therapeutic and diagnostic use.

Pancreatic Incidentaloma

Pancreatic incidentalomas (PIs) represent a clinical entity increasingly recognized due to advances in and easier access to imaging techniques. By definition, PIs should be detected during abdominal imaging performed for indications other than a pancreatic disease. They range from small cysts to invasive cancer. The incidental diagnosis of pancreatic cancer can contribute to early diagnosis and treatment. On the other hand, inadequate management of PIs may result in overtreatment and unneeded morbidity. Therefore, there is a strong need to evaluate the nature and clinical features of individual PIs. In this review, we summarize the major characteristics related to PIs and present suggestions for their management.

Proteomes of Extracellular Vesicles From Pancreatic Cancer Cells and Cancer-Associated Fibroblasts

OBJECTIVES

Extracellular vesicles (EVs) are lipid bound vesicles secreted by cells into the extracellular environment. Studies have implicated EVs in cell proliferation, epithelial-mesenchymal transition, metastasis, angiogenesis, and mediating the interaction of tumor cells and microenvironment. A systematic characterization of EVs from pancreatic cancer cells and cancer-associated fibroblasts (CAFs) would be valuable for studying the roles of EV proteins in pancreatic tumorigenesis.

METHODS

Proteomic and functional analyses were applied to characterize the proteomes of EVs released from 5 pancreatic cancer lines, 2 CAF cell lines, and a normal pancreatic epithelial cell line (HPDE).

RESULTS

More than 1400 nonredundant proteins were identified in each EV derived from the cell lines. The majority of the proteins identified in the EVs from the cancer cells, CAFs, and HPDE were detected in all 3 groups, highly enriched in the biological processes of vesicle-mediated transport and exocytosis. Protein networks relevant to pancreatic tumorigenesis, including epithelial-mesenchymal transition, complement, and coagulation components, were significantly enriched in the EVs from cancer cells or CAFs.

CONCLUSIONS

These findings support the roles of EVs as a potential mediator in transmitting epithelial-mesenchymal transition signals and complement response in the tumor microenvironment and possibly contributing to coagulation defects related to cancer development.

Construction of simple and sensitive pancreatitis related microRNA detection strategy via self-priming triggered cascade signal amplification

Pancreatic diseases, such as pancreatitis and pancreatic cancer, remain the most threatening gastrointestinal diseases with a high mortality due to atypical symptoms. MicroRNA plays crucial roles in regulating metastasis and cell proliferation of pancreatic cancer, constituting important biomarkers for the early diagnosis of pancreatic cancers. Herein, we develop a sensitive and simple exosomal miRNA detection method with only a dual-hairpin-probe. In detail, the dual-hairpin-probe is constructed through combination of two functional sections for both target miRNA identification and signal amplification. With only one probe, the method possesses the capability to avoid interferences from concentration changes of other probes, and exhibits a higher stability which is demonstrated through the obtained low coefficients of variation (CV) of 6.73%. With let-7a as detection target, the LOD of the established method is determined to be 243 aM, while maintaining a high discriminating capability towards let-7a homogenous miRNAs.

Extracellular vesicle-derived microRNAs in pancreatic juice as biomarkers for detection of pancreatic ductal adenocarcinoma

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is usually diagnosed in an advanced stage, with minimal likelihood of long-term survival. Only a small subset of patients are diagnosed with early (T1) disease. Early detection is challenging due to the late onset of symptoms and limited visibility of sub-centimeter cancers on imaging. A novel approach is to support the clinical diagnosis with molecular markers. MicroRNA derived from extracellular vehicles (EVs) in blood has shown promise as a potential biomarker for pancreatic neoplasia, but microRNA derived from pancreatic juice (PJ) may be a more sensitive biomarker, given that is in close contact with ductal cells from which PDAC arises. This study aims to evaluate and compare the performance of PJ- and serum-derived EV-miRNA for the detection of PDAC.

METHODS

PJ was collected from the duodenum during EUS after secretin stimulation from 54 patients with PDAC and 118 non-malignant controls. Serum was available for a subset of these individuals. MiR-16, miR-21, miR-25, miR-155 and miR-210 derived from EVs isolated from PJ and serum were analyzed by qPCR, and serum CA19-9 levels were determined by electrochemiluminescence immunoassay. For statistical analysis, either a Mann-Whitney U test or a Wilcoxon Signed Rank test was performed. ROC curves and AUC were used to assess the sensitivity and specificity of miR expression for PDAC detection.

RESULTS

Expression of EV-miR-21, EV-miR-25 and EV-miR-16 were increased in cases vs controls in PJ, while only EV-miR-210 was increased in serum. The potential to detect PC was good for a combination of PJ EV-miR-21, EV-miR-25, EV-miR-16 and serum miR-210, CA-19-9, with an area under the curve of 0.91, a specificity of 84.2% and a sensitivity of 81.5%.

CONCLUSION

Detection of miRNA from EVs in PJ is feasible. A combined panel of PJ EV-miR-21, EV-miR-25, EV-miR-16, and serum EV-miR-210 and CA19-9 distinguishes cases with PDAC from controls undergoing surveillance with a specificity of 81.5% and sensitivity of 84.2%.

CD63-positive extracellular vesicles are potential diagnostic biomarkers of pancreatic ductal adenocarcinoma

Background

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest gastrointestinal cancers with a 5-year survival rate of less than 10%. Biomarkers for early PDAC detection are useful in treating patients with PDAC. Extracellular vesicles (EVs) are lipid-bound vesicles that are potential biomarkers of various diseases such as PDAC. In this study, we quantitatively measured the serum levels of EVs (CD63⁺-EVs) or platelet-derived EVs (CD41⁺- and CD61⁺-EVs) and evaluated their potential use as biomarkers of PDAC.

Methods

We measured the serum levels of CD63⁺-, CD41⁺-, CD61⁺-EVs using sandwich enzyme-linked immunosorbent assay based on Tim4 with specificity for phosphatidylserine on EVs in age- and sex-matched healthy controls (HCs, n = 39) and patients with PDAC (n = 39). We also examined the effect of tumor burden on the serum EV levels after surgical resection (n = 28). CA19-9, a clinical PDAC biomarker, was also measured for comparison.

Results

Serum levels of CD63⁺-EVs, CD41⁺-EVs, and CD61⁺-EVs were significantly increased in patients with PDAC compared to HCs. Receiver operating characteristic analysis revealed that CD63⁺-EVs exhibited the highest diagnostic performance to discriminate patients with PDAC from HCs (area under the curve (AUC): 0.846), which was comparable to CA19-9 (AUC: 0.842). CA19-9 showed lower AUC values in early stages (I–II, AUC: 0.814) than in late stages (III–IV, AUC: 0.883) PDAC. Conversely, CD63⁺-EVs, CD41⁺-EVs, and CD61⁺-EVs showed comparable AUCs between early- and late-stage PDAC. The combined use of CA19-9 and CD63⁺-EVs showed a higher diagnostic performance for early-stage PDAC (AUC: 0.903) than CA19-9. The serum levels of CD63⁺-EVs, CD41⁺-EVs, CD61⁺-EVs, and CA19-9 decreased significantly after surgical resection, demonstrating that EVs are increased in sera of patients depending on the tumor burden.

Conclusions

The serum levels of CD63⁺-EVs and platelet-derived EVs (CD41⁺-EVs, CD61⁺-EVs) are increased in patients with PDAC than HCs. Since CD63⁺-EVs showed a high AUC to discriminate patients with PDAC from HCs; they might be useful as potential biomarkers for PDAC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02228-7.

Terpinen-4-ol inhibits the proliferation and mobility of pancreatic cancer cells by downregulating Rho-associated coiled-coil containing protein kinase 2

Terpinen-4-ol (T4O), a compound isolated from the seeds of turmeric, has exhibited anti-malignancy, anti-aging, and anti-inflammatory properties in previous studies. However, the specific effects and molecular mechanisms of T4O on pancreatic cancer (PC) cells remain largely unknown. In this study, we demonstrated that T4O markedly suppressed PC cell proliferation and colony formation in vitro and induced apoptosis. Similarly, T4O significantly inhibited the migration and invasion of PC cells in vitro. Through RNA sequencing, 858 differentially expressed genes (DEGs) were identified, which were enriched in the Rhodopsin (RHO)/ Ras homolog family member A (RHOA) signaling pathway. Rho-associated coiled-coil containing protein kinase 2 (ROCK2), a DEG enriched in the RHO/RHOA signaling pathway, was considered as a key target of T4O in PC cells; it was significantly reduced after T4O treatment, highly expressed in PC tissues, and negatively associated with patient outcome. Overexpression of ROCK2 significantly reduced the inhibitory effects of T4O on PC cell proliferation and mobility. Moreover, T4O inhibited cell proliferation in vivo and decreased the Ki-67, cell nuclear antigen, EMT markers, and ROCK2 expression. In conclusion, we consider that T4O can suppress the malignant biological behavior of PC by reducing the expression of ROCK2, thus contributing to PC therapy.

Clinical features and prognostic impact of asymptomatic pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is highly lethal, and early diagnosis is challenging. Because patients who present with symptoms generally have advanced-stage diseases, analysis of asymptomatic PDAC provides invaluable information for developing strategies for early diagnosis. Here, we reviewed 577 patients with PDAC (372 diagnosed with symptoms [symptomatic group] and 205 without symptoms [asymptomatic group]) diagnosed at our institute. Among the 205 asymptomatic PDAC patients, 109 were detected during follow-up/work-up for other diseases, 61 because of new-onset or exacerbation of diabetes mellitus, and 35 in a medical check-up. Asymptomatic PDAC is characterized by smaller tumor size, earlier disease stage, and higher resectability than those of symptomatic PDAC. In 22.7% of asymptomatic cases, indirect findings, e.g., dilatation of the main pancreatic duct, triggered PDAC detection. Although pancreatic tumors were less frequently detected, overall abnormality detection rates on imaging studies were nearly 100% in asymptomatic PDAC. Asymptomatic PDAC had a better prognosis (median survival time, 881 days) than symptomatic PDAC (342 days, P < 0.001). In conclusion, diagnosis of PDAC in the asymptomatic stage is associated with early diagnosis and a better prognosis. Incidental detection of abnormal findings during the follow-up/work-up for other diseases provides important opportunities for early diagnosis of asymptomatic PDAC.

Advances in the Application of Exosomes Identification Using Surface-Enhanced Raman Spectroscopy for the Early Detection of Cancers

Exosomes are small nanoscale vesicles with a double-layered lipid membrane structure secreted by cells, and almost all types of cells can secrete exosomes. Exosomes carry a variety of biologically active contents such as nucleic acids and proteins, and play an important role not only in intercellular information exchange and signal transduction, but also in various pathophysiological processes in the human body. Surface-enhanced Raman Spectroscopy (SERS) uses light to interact with nanostructured materials such as gold and silver to produce a strong surface plasmon resonance effect, which can significantly enhance the Raman signal of molecules adsorbed on the surface of nanostructures to obtain a rich fingerprint of the sample itself or Raman probe molecules with ultra-sensitivity. The unique advantages of SERS, such as non-invasive and high sensitivity, good selectivity, fast analysis speed, and low water interference, make it a promising technology for life science and clinical testing applications. In this paper, we briefly introduce exosomes and the current main detection methods. We also describe the basic principles of SERS and the progress of the application of unlabeled and labeled SERS in exosome detection. This paper also summarizes the value of SERS-based exosome assays for early tumor diagnosis.

Bone mesenchymal stem cell-derived exosomal microRNA-7-5p inhibits progression of acute myeloid leukemia by targeting OSBPL11

BACKGROUND

Acute myeloid leukemia (AML) is a malignant clonal disease of hematopoietic stem- and progenitor-cell origin. AML features massive proliferation of abnormal blasts and leukemia cells in the bone marrow and the inhibition of normal hematopoiesis at onset. Exosomes containing proteins or nucleic acids are secreted by cells; they participate in intercellular communication and serve as key modulators of hematopoiesis. The purpose of this study was to investigate the effects of exosomes derived from bone marrow mesenchymal stem cells (BMSCs) on the regulation of AML and the underlying mechanisms mediated by microRNA (miRNA).

METHODS

Dysregulated miR-7-5p in AML patients was identified using qRT-PCR and its clinical significance was explored. Bioinformatic analysis revealed the target gene OSBPL11 that could be regulated by miR-7-5p. The findings were validated using a dual-luciferase reporter assay and western blotting. The functional genes of the PI3K/AKT/mTOR signaling pathway were identified, and the functional significance of miR-7-5p in AML cells was determined using a functional recovery assay. AML cells were co-cultured with exosomes originating from BMSCs overexpressing miR-7-5p to determine cell-cell regulation by Exo-miR-7-5p, as well as in vitro and in vivo functional validation via gain- and loss-of-function methods.

RESULTS

Expression of miR-7-5p was decreased in AML patients and cells. Overexpression of miR-7-5p curbed cellular proliferation and promoted apoptosis. Overexpression of OSBPL11 reversed the tumorigenic properties of miR-7-5p in AML cells in vitro. Exo-miR-7-5p derived from BMSCs induced formation of AML cells prone to apoptosis and a low survival rate, with OSBPL11 expression inhibited through the PI3K/AKT/mTOR signaling pathway. Exo-miR-7-5p derived from BMSCs exhibited tumor homing effects in vitro and in vivo, and inhibited AML development.

CONCLUSIONS

Exo-miR-7-5p derived from BMSCs negatively regulates OSBPL11 by suppressing the phosphorylation of the PI3K/AKT/mTOR signaling pathway, thereby inhibiting AML proliferation and promoting apoptosis. The data will inform the development of AML therapies based on BMSC-derived exosomes.

Serum exosomal miR-451a acts as a candidate marker for pancreatic cancer

OBJECTIVES

The aim of this study was to explore the diagnostic efficiency of serum exosomal miR-451a as a novel biomarker for pancreatic cancer.

METHODS

Serum samples were collected prior to treatment. First, we analyzed microRNA (miRNA) profiles in serum exosomes from eight pancreatic cancer patients and eight healthy volunteers. We then validated the usefulness of the selected exosomal miRNAs as biomarkers in another 191 pancreatic cancer patients, 95 pancreatic benign disease (PB) patients, and 90 healthy controls.

RESULTS

The expression of miR-451a in serum-derived exosomes from pancreatic cancer patients was significantly upregulated compared with those from PB patients and healthy individuals. Serum exosomal miR-451a showed excellent diagnostic power in identifying pancreatic cancer patients. In addition, exosomal miR-451a showed a significant association with clinical stage and distant metastasis in pancreatic cancer, and the expression level of serum exosomal miR-451a was sensitive to therapy and relapse.

CONCLUSIONS

Serum exosomal miR-451a might serve as a novel diagnostic marker for pancreatic cancer.

Small extracellular vesicles: from mediating cancer cell metastasis to therapeutic value in pancreatic cancer

Pancreatic cancer is a highly malignant tumor and, is extremely difficult to diagnose and treat. Metastasis is one of the critical steps in the development of cancer and uses cell to cell communication to mediate changes in the microenvironment. Small extracellular vesicles (sEVs)-carry proteins, nucleic acids and other bioactive substances, and are important medium for communication between cells. There are two primary steps in sVEs-mediated metastasis: communication between pancreatic cancer cells and their surrounding microenvironment; and the communication between primary tumor cells and distant organ cells in distant organs that promotes angiogenesis, reshaping extracellular matrix, forming immunosuppressive environment and other ways to form appropriate pre-metastasis niche. Here, we explore the mechanism of localization and metastasis of pancreatic cancer and use sEVs as early biomarkers for the detection and treatment of pancreatic cancer. Video Abstract.

Exosomes derived from 3D-cultured MSCs improve therapeutic effects in periodontitis and experimental colitis and restore the Th17 cell/Treg balance in inflamed periodontium

Although mesenchymal stem cell-derived exosomes (MSC-exos) have been shown to have therapeutic effects in experimental periodontitis, their drawbacks, such as low yield and limited efficacy, have hampered their clinical application. These drawbacks can be largely reduced by replacing the traditional 2D culture system with a 3D system. However, the potential function of MSC-exos produced by 3D culture (3D-exos) in periodontitis remains elusive. This study showed that compared with MSC-exos generated via 2D culture (2D-exos), 3D-exos showed enhanced anti-inflammatory effects in a ligature-induced model of periodontitis by restoring the reactive T helper 17 (Th17) cell/Treg balance in inflamed periodontal tissues. Mechanistically, 3D-exos exhibited greater enrichment of miR-1246, which can suppress the expression of Nfat5, a key factor that mediates Th17 cell polarization in a sequence-dependent manner. Furthermore, we found that recovery of the Th17 cell/Treg balance in the inflamed periodontium by the local injection of 3D-exos attenuated experimental colitis. Our study not only showed that by restoring the Th17 cell/Treg balance through the miR-1246/Nfat5 axis, the 3D culture system improved the function of MSC-exos in the treatment of periodontitis, but also it provided a basis for treating inflammatory bowel disease (IBD) by restoring immune responses in the inflamed periodontium.

Long Non-Coding RNAs in Epithelial-Mesenchymal Transition of Pancreatic Cancer

Non-coding RNAs (ncRNAs), or RNA molecules that do not code for proteins, are generally categorized as either small or long ncRNA (lncRNA) and are involved in the pathogenesis of several diseases including many cancers. Identification of a large number of ncRNAs could help to elucidate previously unknown mechanisms in phenotype regulation. Some ncRNAs are encapsulated by extracellular vesicles (EVs) and transferred to recipient cells to regulate cellular processes, including epigenetic and post-transcriptional regulations. Recent studies have uncovered novel molecular mechanisms and functions of lncRNAs in pancreatic ductal adenocarcinoma (PDAC), one of the most intractable cancers that is highly invasive and metastatic. As the epithelial-mesenchymal transition (EMT) triggers tumor cell invasion and migration, clarification of the roles of lncRNA in EMT and tumor cell stemness would be critical for improving diagnostic and therapeutic approaches in metastatic cancers. This review provides an overview of relevant studies on lncRNA and its involvement with EMT in PDAC. Emerging knowledge offers evidence for the dysregulated expression of lncRNAs and essential insights into the potential contribution of both lncRNAs and EVs in the pathogenesis of PDAC. Future directions and new clinical applications for PDAC are also discussed.

Roles and mechanisms of exosomal non-coding RNAs in human health and diseases

Exosomes play a role as mediators of cell-to-cell communication, thus exhibiting pleiotropic activities to homeostasis regulation. Exosomal non-coding RNAs (ncRNAs), mainly microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), are closely related to a variety of biological and functional aspects of human health. When the exosomal ncRNAs undergo tissue-specific changes due to diverse internal or external disorders, they can cause tissue dysfunction, aging, and diseases. In this review, we comprehensively discuss the underlying regulatory mechanisms of exosomes in human diseases. In addition, we explore the current knowledge on the roles of exosomal miRNAs, lncRNAs, and circRNAs in human health and diseases, including cancers, metabolic diseases, neurodegenerative diseases, cardiovascular diseases, autoimmune diseases, and infectious diseases, to determine their potential implication in biomarker identification and therapeutic exploration.

The roles of exosomal immune checkpoint proteins in tumors

Targeting immune checkpoints has achieved great therapeutic effects in the treatment of early-stage tumors. However, most patients develop adaptive resistance to this therapy. The latest evidence demonstrates that tumor-derived exosomes may play a key role in systemic immune suppression and tumor progression. In this article, we highlight the role of exosomal immune checkpoint proteins in tumor immunity, with an emphasis on programmed death ligand 1 (PD-L1) and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), as well as emerging evidence on roles of T cell immunoglobulin-3 (TIM-3), arginase 1 (ARG1), and estrogen receptor binding fragment-associated antigen 9 (EBAG9) expressed by exosomes.

Evolving Landscape of Long Non-coding RNAs in Cerebrospinal Fluid: A Key Role From Diagnosis to Therapy in Brain Tumors

Long non-coding RNAs (lncRNAs) are a type of non-coding RNAs that act as molecular fingerprints and modulators of many pathophysiological processes, particularly in cancer. Specifically, lncRNAs can be involved in the pathogenesis and progression of brain tumors, affecting stemness/differentiation, replication, invasion, survival, DNA damage response, and chromatin dynamics. Furthermore, the aberrations in the expressions of these transcripts can promote treatment resistance, leading to tumor recurrence. The development of next-generation sequencing technologies and the creation of lncRNA-specific microarrays have boosted the study of lncRNA etiology. Cerebrospinal fluid (CSF) directly mirrors the biological fluid of biochemical processes in the brain. It can be enriched for small molecules, peptides, or proteins released by the neurons of the central nervous system (CNS) or immune cells. Therefore, strategies that identify and target CSF lncRNAs may be attractive as early diagnostic and therapeutic options. In this review, we have reviewed the studies on CSF lncRNAs in the context of brain tumor pathogenesis and progression and discuss their potential as biomarkers and therapeutic targets.

Plasma-Derived Exosome MiR-19b Acts as a Diagnostic Marker for Pancreatic Cancer

Background

Diagnosis of pancreatic cancer (Pca) is challenging. This study investigated the value of plasma-derived exosome miR-19b (Exo-miR-19b) in diagnosing patients with Pca.

Methods

Plasma was collected from 62 patients with Pca, 30 patients with other pancreatic tumor (OPT), 23 patients with chronic pancreatitis (CP), and 53 healthy volunteers. MiR-19b levels in plasma-derived exosomes were detected.

Results

Plasma-derived Exo-miR-19b levels normalized using miR-1228 were significantly lower in Pca patients than in patients with OPT, CP patients, and healthy volunteers. The diagnostic values of Exo-miR-19b normalized using miR-1228 were superior to those of serum cancer antigen 19-9 (CA19-9) in differentiating Pca patients from healthy volunteers (area under the curve (AUC): 0.942 vs. 0.813, p = 0.0054), potentially better than those of CA19-9 in differentiating Pca patients from CP patients (AUC: 0.898 vs. 0.792, p = 0.0720), and equivalent to those of CA19-9 in differentiating Pca patients from patients with OPT (AUC: 0.810 vs. 0.793, p = 0.8206). When normalized using Caenorhabditis elegans miR-39 (cel-miR-39), Exo-miR-19b levels in Pca patients were significantly higher than those in patients with OPT, CP patients, and healthy volunteers. The diagnostic values of Exo-miR-19b normalized using cel-miR-39 were equivalent to those of CA19-9 in differentiating Pca patients from healthy volunteers (AUC: 0.781 vs. 0.813, p = 0.6118) and CP patients (AUC: 0.672 vs. 0.792, p = 0.1235), while they were inferior to those of CA19-9 in differentiating Pca patients from patients with OPT (AUC: 0.631 vs. 0.793, p = 0.0353).

Conclusion

Plasma-derived Exo-miR-19b is a promising diagnostic marker for Pca. The diagnostic value of plasma-derived Exo-miR-19b normalized using miR-1228 is superior to that of serum CA19-9 in differentiating patients with Pca from healthy volunteers.

[Research progress of microRNA in laryngeal squamous cell carcinoma]

Laryngeal carcinoma is one of the most common malignant tumors in the area of head and neck, and the main pathological type is laryngeal squamous cell carcinoma. Due to the fact that the disease usually have no overt clinical symptoms at the early stage and easy to relapse, it has a poor prognosis and low five-year survival rate. microRNA is a class of endogenous, non-coding RNA with a length of 19-25 nucleotides. microRNAs, mainly regulate the expression of target genes at the post-transcriptional level after complementing and pairing with the 3'-UTR area of the target gene. Studies have shown that the abnormal expression of microRNA is closely related to the occurrence, development, metastasis and prognosis of various cancers including laryngeal carcinoma. In this article, the research progress of microRNA in laryngeal squamous cell carcinoma is reviewed.

Metastatic pancreatic cancer: Mechanisms and detection (Review)

Pancreatic cancer (PC) is a lethal malignancy. Its prevalence rate remains low but continues to grow each year. Among all stages of PC, metastatic PC is defined as late-stage (stage IV) PC and has an even higher fatality rate. Patients with PC do not have any specific clinical manifestations. Most cases are inoperable at the time-point of diagnosis. Prognosis is also poor even with curative-intent surgery. Complications during surgery, postoperative pancreatic fistula and recurrence with metastatic foci make the management of metastatic PC difficult. While extensive efforts were made to improve survival outcomes, further elucidation of the molecular mechanisms of metastasis poses a formidable challenge. The present review provided an overview of the mechanisms of metastatic PC, summarizing currently known signaling pathways (e.g. epithelial-mesenchymal transition, NF-κB and KRAS), imaging that may be utilized for early detection and biomarkers (e.g. carbohydrate antigen 19-9, prostate cancer-associated transcript-1, F-box/LRR-repeat protein 7 and tumor stroma), giving insight into promising therapeutic targets.

The significance of exosomal RNAs in the development, diagnosis, and treatment of pancreatic cancer

Exosomes are single-membrane, secreted organelles with a diameter of 30–200 nm, containing diverse bioactive constituents, including DNAs, RNAs, proteins, and lipids, with prominent molecular heterogeneity. Extensive studies indicate that exosomal RNAs (e.g., microRNAs, long non-coding RNAs, and circular RNAs) can interact with many types of cancers, associated with several hallmark features like tumor growth, metastasis, and resistance to therapy. Pancreatic cancer (PaCa) is among the most lethal cancers worldwide, emerging as the seventh foremost cause of cancer-related death in both sexes. Hence, revealing the specific pathogenesis and improving the clinical diagnosis and treatment process are urgently required. As the study of exosomes has become an active area of research, the functional connections between exosomes and PaCa have been deeply investigated. Among these, exosomal RNAs seem to play a significant role in the development, diagnosis, and treatment of PaCa. Exosomal RNAs delivery ultimately modulates the various features of PaCa, and many scholars have interpreted how exosomal RNAs contribute to the proliferation, angiogenesis, migration, invasion, metastasis, immune escape, and drug resistance in PaCa. Besides, recent studies emphasize that exosomal RNAs may serve as diagnostic and prognostic biomarkers or therapeutic targets for PaCa. In this review, we will introduce these recent insights focusing on the discoveries of the relationship between exosomal RNAs and PaCa, and the potentially diagnostic and therapeutic applications of exosomes in PaCa.

Serum Extracellular Vesicle-Derived miR-124-3p as a Diagnostic and Predictive Marker for Early-Stage Acute Ischemic Stroke

Background: A delay in the diagnosis of acute ischemic stroke (AIS) reduces the eligibility and outcome of patients for thrombolytic therapy. Therefore, early diagnosis and treatment of AIS are crucial. The present study evaluated the sensitivity and accuracy of serum extracellular vesicle (EV)-derived miR-124-3p in the diagnosis and prediction of AIS.

Methods: An miRNA expression profile was downloaded from Gene Expression Omnibus (GEO) database and analyzed by R software. EVs were harvested from the serum of AIS patients using a total exosome isolation kit and characterized by Western blotting, a transmission electron microscope, and the nanoparticle tracking analysis. BV2 microglia were pre-stimulated with lipopolysaccharide (LPS), followed by miR-124-3p treatment for 24 h and subsequent analysis of viability, apoptosis, and migration (scratch assay), and Western blotting. The relative expression of the selected genes was assessed by qRT-PCR. The phosphorylation of Erk1/2, PI3K/Akt, and p38MAPK in BV2 microglia cells was evaluated by Western blotting, while the luciferase reporter gene assay detected the correlation between key genes involved in the pro-inflammatory signaling pathways and miR-124-3p.

Results:hsa-miR-124-3p was downregulated in AIS serum compared to the non-AIS serum (p < 0.05), and the gene expression of has-miR-124-3p in EVs was negatively correlated with serum pro-inflammatory cytokines and the NIHSS (p < 0.05). In addition, miR-124-3p promoted the viability and inhibited the apoptosis of LPS-induced BV2 microglia. Furthermore, miR-124-3p reduced the phosphorylation of Erk1/2, PI3K/Akt, and p38MAPK, and promoted the migration in LPS-induced BV2 microglia (p < 0.05).

Conclusion: Serum EV-derived miR-124-3p serves as a diagnostic and predictive marker for early-stage AIS.

Exosomal microRNA in Pancreatic Cancer Diagnosis, Prognosis, and Treatment: From Bench to Bedside

Simple Summary

Pancreatic cancer is the fourth leading cause of cancer death in the United States and over 90% of the patients suffer from pancreatic ductal adenocarcinoma (PDAC). PDAC is the most lethal gastrointestinal malignancies and only 10% of the people survive more than 5 years, therefore, novel diagnostic, prognostic, and therapeutic strategies are an immediate necessity. Studies have demonstrated microRNAs in bodily fluids that are bound with membranes (exosomes) can act as stable biomarkers both for disease development and metastasis. The diagnostic, prognostic, as well as therapeutic roles of exosomal microRNAs in pancreatic cancer have been discussed in this review.

Abstract

Pancreatic cancer is the fourth leading cause of cancer death among men and women in the United States, and pancreatic ductal adenocarcinoma (PDAC) accounts for more than 90% of pancreatic cancer cases. PDAC is one of the most lethal gastrointestinal malignancies with an overall five-year survival rate of ~10%. Developing effective therapeutic strategies against pancreatic cancer is a great challenge. Novel diagnostic, prognostic, and therapeutic strategies are an immediate necessity to increase the survival of pancreatic cancer patients. So far, studies have demonstrated microRNAs (miRNAs) as sensitive biomarkers because of their significant correlation with disease development and metastasis. The miRNAs have been shown to be more stable inside membrane-bound vesicles in the extracellular environment called exosomes. Varieties of miRNAs are released into the body fluids via exosomes depending on the normal physiological or pathological conditions of the body. In this review, we discuss the recent findings on the diagnostic, prognostic, and therapeutic roles of exosomal miRNAs in pancreatic cancer.

Tumor-Stromal Interactions in a Co-Culture Model of Human Pancreatic Adenocarcinoma Cells and Fibroblasts and Their Connection with Tumor Spread

One key feature of pancreatic ductal adenocarcinoma (PDAC) is a dense desmoplastic reaction that has been recognized as playing important roles in metastasis and therapeutic resistance. We aim to study tumor-stromal interactions in an in vitro coculture model between human PDAC cells (Capan-1 or PL-45) and fibroblasts (LC5). Confocal immunofluorescence, Enzyme-Linked Immunosorbent Assay (ELISA), and Western blotting were used to evaluate the expressions of activation markers; cytokines arrays were performed to identify secretome profiles associated with migratory and invasive properties of tumor cells; extracellular vesicle production was examined by ELISA and transmission electron microscopy. Coculture conditions increased FGF-7 secretion and α-SMA expression, characterized by fibroblast activation and decreased epithelial marker E-cadherin in tumor cells. Interestingly, tumor cells and fibroblasts migrate together, with tumor cells in forming a center surrounded by fibroblasts, maximizing the contact between cells. We show a different mechanism for tumor spread through a cooperative migration between tumor cells and activated fibroblasts. Furthermore, IL-6 levels change significantly in coculture conditions, and this could affect the invasive and migratory capacities of cells. Targeting the interaction between tumor cells and the tumor microenvironment might represent a novel therapeutic approach to advanced PDAC.

Power and promise of exosomes as clinical biomarkers and therapeutic vectors for liquid biopsy and cancer control

Exosomes, microvesicles derived from the nuclear endosome and plasma membrane, can be released into the extracellular environment to act as mediators between the cell membrane and cytoplasmic proteins, lipids, or RNA. Exosomes are considered effective carriers of intercellular signals in prokaryotes and eukaryotes, because of their ability to efficiently transfer proteins, lipids, and nucleic acids between cellular compartments. Since the 2007 discovery that exosomes carry bioactive substances, exosomes have been intensively researched. In various physiological and pathological processes, exosomes play important biological roles by specifically combining with receptor cells and transmitting information. Their stable biological characteristics, diversity of contents, non-invasiveness path for introducing signaling molecules, and ability for rapid detection make exosomes a promising clinical diagnostic marker for potentially many pathological conditions, including cancers. Exosomes are not only considered biomarkers and prognostic disease factors, but also have potential as gene carriers and drug delivery vectors, and have important clinical significance and application potential in the fields of cancer diagnosis, prognosis, and treatment.

Virus-mimetic systems for cancer diagnosis and therapy

Over past decades, various strategies have been developed to enhance the delivery efficiency of therapeutics and imaging agents to tumor tissues. However, the therapeutic outcome of tumors to date have not been significantly improved, which can be partly attributed to the weak targeting ability, fast elimination, and low stability of conventional delivery systems. Viruses are the most efficient agents for gene transfer, serving as a valuable source of inspiration for designing nanoparticle-based delivery systems. Based on the properties of viruses, including well-defined geometry, precise composition, easy modification, stable construction, and specific infection, researchers attempt to design biocompatible delivery vectors by mimicking virus assembly and using the vector system to selectively concentrate drugs or imaging probes in tumors with mitigated toxicity and improved efficacy. In this review, we introduce common viruses features and provide an overview of various virus-mimetic strategies for cancer therapy and diagnosis. The challenges faced by virus-mimetic systems are also discussed. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.