Cancer-associated fibroblast exosomes regulate survival and proliferation of pancreatic cancer cells

The crosstalk within tumor microenvironment and exosomes in pancreatic cancer

Pancreatic cancer is one of the most malignant tumors with a grim prognosis. Patients develop chemoresistance that drastically decreases their survival. The chemoresistance is mainly attributed to deficient vascularization of the tumor, intratumoral heterogeneity and pathophysiological barrier due to the highly desmoplastic tumor microenvironment. The interactions of cells that constitute the tumor microenvironment change its architecture into a cancer-permissive environment and stimulate cancer development, metastasis and treatment response. The cell-cell communication in the tumor microenvironment is often mediated by exosomes that harbour a diverse repertoire of molecular cargo, such as proteins, lipids, and nucleic acid, including messenger RNAs, non-coding RNAs and DNA. Therefore, exosomes can serve as potential targets as biomarkers and improve the clinical management of pancreatic cancer to overcome chemoresistance. This review critically elucidates the role of exosomes in cell-cell communication within the tumor microenvironment and how these interactions can orchestrate chemoresistance.

The function of microRNA related to cancer-associated fibroblasts in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignant tumor characterized by a poor prognosis. A prominent feature of PDAC is the rich and dense stroma present in the tumor microenvironment (TME), which significantly hinders drug penetration. Cancer-associated fibroblasts (CAFs), activated fibroblasts originating from various cell sources, including pancreatic stellate cells (PSCs) and mesenchymal stem cells (MSCs), play a critical role in PDAC progression and TME formation. MicroRNAs (miRNAs) are small, single-stranded non-coding RNA molecules that are frequently involved in tumorigenesis and progression, exhibiting either oncolytic or oncogenic activity. Increasing evidence suggests that aberrant expression of miRNAs can mediate interactions between cancer cells and CAFs, thereby providing novel therapeutic targets for PDAC treatment. In this review, we will focus on the potential roles of miRNAs that target CAFs or CAFs-derived exosomes in PDAC progression, highlighting the feasibility of therapeutic strategies aimed at restoring aberrantly expressed miRNAs associated with CAFs, offering new pathways for the clinical management of PDAC.

Metabolic reprogramming of drug resistance in pancreatic cancer: mechanisms and effects

Pancreatic cancer is a highly aggressive gastrointestinal malignancy, often termed the "king of cancers" due to its notoriously high mortality rate. Its clinical characteristics, including late diagnosis, low surgical resectability, high recurrence rates, significant chemoresistance, and poor prognosis have collectively driven the persistent rise in incidence and mortality. Despite ongoing advancements in therapeutic strategies, the management of pancreatic cancer, particularly at advanced stages, remains challenging. Chemotherapy remains the mainstay of current treatment. However, the prevalent problem of chemotherapy resistance poses a significant obstacle to effective treatment. Metabolic reprogramming, characterized by alterations in glucose metabolism, lipid biosynthesis, and amino acid utilization, supports the high energy demands and rapid proliferation of cancer cells. Emerging evidence suggests that these metabolic changes, possibly mediated by epigenetic mechanisms, also contribute to tumorigenesis and metastasis. These findings highlight the critical role of metabolic alterations in pancreatic cancer pathogenesis. This review explores the relationship between metabolic reprogramming and chemotherapy resistance, discussing underlying mechanisms and summarizing preclinical studies and drug development targeting metabolism. The aim is to provide a comprehensive perspective on potential therapeutic strategies for pancreatic cancer.

Fibrotic Fortresses and Therapeutic Frontiers: Pancreatic Stellate Cells and the Extracellular Matrix in Pancreatic Cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a unique tumor microenvironment (TME) that plays pivotal roles in cancer progression, angiogenesis, metastasis, and drug resistance. This complex and dynamic ecosystem comprises cancer cells, stromal cells, and extracellular matrix (ECM) components, which interact synergistically to drive cancer aggressiveness. Among the stromal cells, cancer-associated fibroblasts (CAFs) and pancreatic stellate cells (PSCs), mainly accepted as a group of CAFs, are central players in shaping the desmoplastic, hypoxic, and immunosuppressive stroma of PDAC. PSCs, the most abundant stromal cells in PDAC, are resident pancreatic cells that undergo phenotypic changes upon activation, driving tumor progression through the secretion of cytokines, growth factors, ECM components (e.g., collagen, hyaluronic acid, fibronectin), and matrix metalloproteinases. In addition to cellular elements, ECM components significantly contribute to cancer aggressiveness by forming a physical barrier that hinders drug penetration, activating signaling pathways through specific receptor interactions, and generating peptides originating from the fragmentation of proteins to induce cancer migration. Regarding their critical roles in tumor progression, therapeutic approaches targeting PSCs and the ECM have garnered increasing interest in recent years. However, PSCs and stromal components may exhibit dual roles, with the potential to both promote and suppress tumor progression under different conditions. Therefore, targeting PSCs or stroma may lead to unintended outcomes, including exacerbation of cancer aggressiveness.

METHODS

This review focuses on the multifaceted roles of PSCs in PDAC, particularly their interactions with cancer cells and their contributions to therapy resistance. Additionally, we discuss current and emerging therapeutic strategies targeting PSCs and the ECM components, including both preclinical and clinical efforts.

CONCLUSION

By synthesizing insights from recent literature, this review provides a comprehensive understanding of the role of PSCs in PDAC pathobiology and highlights potential therapeutic approaches targeting PSCs or ECM components to improve patient outcomes.

Characterization of extracellular vesicle-associated DNA and proteins derived from organotropic metastatic breast cancer cells

BACKGROUND

While primary breast cancer (BC) is often effectively managed, metastasis remains the primary cause of BC-related fatalities. Gaps remain in our understanding of the mechanisms regulating cancer cell organotropism with predilection to specific organs. Unraveling mediators of site-specific metastasis could enhance early detection and enable more tailored interventions. Liquid biopsy represents an innovative approach in cancer involving the analysis of biological materials such as circulating tumor DNA and tumor-derived extracellular vesicles (EV) found in body fluids like blood or urine. This offers valuable insights for characterizing and monitoring tumor genomes to advance personalized medicine in metastatic cancers.

METHODS

We performed in-depth analyses of EV cargo associated with BC metastasis using eight murine cell line models with distinct metastatic potentials and organotropism to the lung, the bone, the liver, and the brain. We characterized the secretome of these cells to identify unique biomarkers specific to metastatic sites.

RESULTS

Small EVs isolated from all cell lines were quantified and validated for established EV markers. Tracking analysis and electron microscopy revealed EV secretion patterns that differed according to cell line. Cell-free (cf)DNA and EV-associated DNA (EV-DNA) were detected from all cell lines with varying concentrations. We detected a TP53 mutation in both EV-DNA and cfDNA. Mass spectrometry-based proteomics analyses identified 698 EV-associated proteins, which clustered according to metastatic site. This analysis highlighted both common EV signatures and proteins involved in cancer progression and organotropism unique to metastatic cell lines. Among these, 327 significantly differentially enriched proteins were quantified with high confidence levels across BC and metastatic BC cells. We found enrichment of specific integrin receptors in metastatic cancer EVs compared to EVs secreted from non-transformed epithelial cells and matched tumorigenic non-metastatic cells. Pathway analyses revealed that EVs derived from parental cancer cells display a cell adhesion signature and are enriched with proteins involved in cancer signaling pathways.

CONCLUSION

Taken together, the characterization of EV cargo in a unique model of BC organotropism demonstrated that EV-DNA and EV proteomes were informative of normal and cancer states. This work could help to identify BC biomarkers associated with site-specific metastasis and new therapeutic targets.

Downregulation of transforming growth factor-β2 enhances the chemosensitivity to gemcitabine with diminished metastasis in pancreatic cancers

Pancreatic cancer is characterized by high rates of metastasis, recurrence, and chemoresistance, contributing to its poor prognosis. Transforming growth factor-β2 (TGF-β2), a member of the TGF-β family, plays a pivotal role in promoting cancer cell metastasis and mediating chemoresistance, particularly in advanced stages of tumor progression. However, the precise role of TGF-β in chemoresistance and metastasis in pancreatic cancer has not been studied yet. In the current study, we investigated the potential of human TGF-β2 antisense oligonucleotides (TGF-β2i) to enhance the chemosensitivity to gemcitabine in pancreatic cancer, using human pancreatic cancer cell lines (hPCCs; PANC-1, MIA PaCa-2, and AsPC-1), a co-culture model with human pancreatic stellate cells (hPSCs), a cancer-associated fibroblast-integrated pancreatic cancer organoid model (CIPCO), and an orthotopic xenograft mouse model. TGF-β2i decreased cell proliferation, migration, and viability in hPCCs, and its combination with gemcitabine exhibited a synergistic effect in PANC-1 and MIA PaCa-2 cells. Flow cytometry demonstrated a decrease in CD44 +CD24 +EpCAMHigh cancer stem-like cell populations following TGF-β2i treatment. In co-culture models, hPSCs-induced enhancement of hPCCs migration was attenuated by TGF-β2i. In the CIPCOs, TGF-β2i suppressed the gemcitabine-induced expression of extracellular matrix components such as COL1A1 and VIM. Furthermore, in an orthotopic mouse model generated by co-inoculating hPCCs and hPSCs into the pancreatic wall, co-treatment of TGF-β2i with gemcitabine significantly delayed tumor growth and metastasis to the liver compared to vehicle control. These findings suggest that TGF-β2i enhances chemosensitivity and suppresses metastatic properties by regulating both tumor-intrinsic and -extrinsic factors, indicating that targeting TGF-β2 could be a promising strategy for managing pancreatic cancer.

The potential application of stroma modulation in targeting tumor cells: focus on pancreatic cancer and breast cancer models

The tumor microenvironment (TME) plays a crucial role in cancer development and spreading being considered as "the dark side of the tumor". Within this term tumor cells, immune components, supporting cells, extracellular matrix and a myriad of bioactive molecules that synergistically promote tumor development and therapeutic resistance, are included. Recent findings revealed the profound impacts of TME on cancer development, serving as physical support, critical mediator and biodynamic matrix in cancer evolution, immune modulation, and treatment outcomes. TME targeting strategies built on vasculature, immune checkpoints, and immuno-cell therapies, have paved the way for revolutionary clinical interventions. On this basis, the relevance of pre-clinical and clinical investigations has rapidly become fundamental for implementing novel therapeutical strategies breaking cell-cell and cell -mediators' interactions between TME components and tumor cells. This review summarizes the key players in the breast and pancreatic TME, elucidating the intricate interactions among cancer cells and their essential role for cancer progression and therapeutic resistance. Different tumors such breast and pancreatic cancer have both different and similar stroma features, that might affect therapeutic strategies. Therefore, this review aims to comprehensively evaluate recent findings for refining breast and pancreatic cancer therapies and improve patient prognoses by exploiting the TME's complexity in the next future.

Exosomes: their role and therapeutic potential in overcoming drug resistance of gastrointestinal cancers

Gastrointestinal cancers are prevalent malignant neoplasms in clinical medicine. The development of drug resistance in gastrointestinal cancers result in tumor recurrence and metastasis and greatly diminish the efficacy of treatment. Exosomes, as the shuttle of intercellular molecular cargoes in tumor micro-environment, secreted from tumor and stromal cells mediate drug resistance by regulating epithelial-mesenchymal transition, drug efflux, stem-like phenotype and cell metabolism. Meanwhile, exosomes have already received tremendous attention in biomedical study as potential drug resistant biomarkers as well as treatment strategy in gastrointestinal cancers. Primary challenge to implement this potential is the ability to obtain high-grade exosomes efficiently; however, exosomes lack standard protocols for their processing and characterization. Furthermore, this field suffers from insufficient standardized reference materials and workflow for purification, detection and analysis of exosomes with defined biological properties. This review summarize the unique biogenesis, composition and novel detection methods of exosomes and informed the underlying correlation between exosomes and drug resistance of gastrointestinal cancers. Moreover, the clinical applications of exosomes are also summarized, might providing novel therapy for the individual treatment of gastrointestinal cancers.

Comprehensive analysis of SQOR involvement in ferroptosis resistance of pancreatic ductal adenocarcinoma in hypoxic environments

Introduction

Pancreatic ductal adenocarcinoma (PDAC) exhibits higher hypoxia level than most solid tumors, and the presence of intratumoral hypoxia is associated with a poor prognosis. However, the identification of hypoxia levels based on pathological images, and the mechanisms regulating ferroptosis resistance, remain to be elucidated. The objective of this study was to construct a deep learning model to evaluate the hypoxia characteristics of PDAC and to explore the role of Sulfide quinone oxidoreductase (SQOR) in hypoxia-mediated ferroptosis resistance.

Methods

Multi-omics data were integrated to analyze the correlation between hypoxia score of PDAC, SQOR expression and prognosis, and ferroptosis resistance level. A deep learning model of Whole Slide Images (WSIs) were constructed to predict the hypoxia level of patients. In vitro hypoxia cell models, SQOR knockdown experiments and nude mouse xenograft models were used to verify the regulatory function of SQOR on ferroptosis.

Results

PDAC exhibited significantly higher hypoxia levels than normal tissues, correlating with reduced overall survival in patients. In slide level, our deep learning model can effectively identify PDAC hypoxia levels with good performance. SQOR was upregulated in tumor tissues and positively associated with both hypoxia score and ferroptosis resistance. SQOR promotes the malignant progression of PDAC in hypoxic environment by enhancing the resistance of tumor cells to ferroptosis. SQOR knockdown resulted in decreased cell viability, decreased migration ability and increased MDA level under hypoxic Ersatin induced conditions. Furthermore, SQOR inhibitor in combination with ferroptosis inducer has the potential to inhibit tumor growth in vivo in a synergistic manner.

Discussion

This study has established a hypoxia detection model of PDAC based on WSIs, providing a new tool for clinical evaluation. The study revealed a new mechanism of SQOR mediating ferroptosis resistance under hypoxia and provided a basis for targeted therapy.

The role of tumor-associated fibroblast-derived exosomes in chemotherapy resistance of colorectal cancer and its application prospect

Colorectal cancer (CRC) is the second most common malignant tumor in the world. With its increasing incidence and younger age trend, its impact on human health has been paid more and more attention. Currently, we have a variety of chemotherapy drugs that can be used to treat colorectal cancer. However, the drug resistance of colorectal cancer has become a significant factor affecting its cure rate. Some studies have reported that exosomes are related to the occurrence of drug resistance. However, the exact mechanism is not precise. Therefore, we focused on the role of cancer associated-fibroblast-derived (CAFs-derived) exosomes in colorectal progression. It was found that cancer cells transmit information through exosome interaction and induce chemotherapy resistance by promoting epithelial-mesenchymal transition (EMT), up-regulating the Wnt/β-catenin signaling pathway, transforming growth factor-β1 (TGF-β1) pathway, promoting angiogenesis and other possible molecular mechanisms. In addition, in terms of clinical significance and therapeutic strategies, we explore the clinical relevance of CAFs-derived exosomes in colorectal cancer patients and their potential as potential biomarkers for predicting chemotherapy response. We also provide a new possible direction for overcoming chemotherapy resistance in colorectal cancer by targeting CAFs-derived exosomes.

Small extracellular vesicles (sEVs) in pancreatic cancer progression and diagnosis

Pancreatic cancer is one of the most aggressive malignancies with poor prognostic outcomes, necessitating the exploration of novel biomarkers and therapeutic targets for early detection and effective treatment. Small extracellular vesicles (sEVs) secreted by cells, have gained considerable attention in cancer research due to their role in intercellular communication and their potential as non-invasive biomarkers. This review focuses on the role of sEVs in the progression of pancreatic cancer and their application as biomarkers. We delve into the biogenesis, composition, and functional implications of sEVs in pancreatic tumor biology, emphasizing their involvement in processes such as tumor growth, metastasis, immune modulation, and chemotherapy resistance. In addition, we discuss the challenges in isolating and characterizing sEVs. The review also highlights recent advances in the utilization of sEV-derived biomarkers for the early diagnosis, prognosis, and monitoring of pancreatic cancer. By synthesizing the latest findings, we aim to underscore the significance of sEVs in pancreatic cancer and their potential to revolutionize patient management through improved diagnostics and targeted therapies.

Risk factors and management of lung cancer in idiopathic pulmonary fibrosis: A comprehensive review

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease. Lung cancer (LC) is among the most crucial comorbidity factors in patients with IPF. IPF patients that are diagnosed with LC have a reduced mean survival time. Therapeutic strategies for LC in patients with IPF need to be adapted according to the individual treatment risk. Life-threatening acute exacerbation (AE) of IPF may occur in association with cancer treatment, thereby severely restricting the therapeutic options for IPF-associated LC. Because LC and anticancer treatments can worsen the prognosis of IPF, the prevention of LC is as critical as managing patients with IPF.

Clinical Impact of Exosome Chemistry in Cancer

As we progress into the 21st century, cancer stands as one of the most dreaded diseases. With approximately one in every four individuals facing a lifetime risk of developing cancer, cancer remains one of the most serious health challenges worldwide. Its multifaceted nature makes it an arduous and tricky problem to diagnose and treat. Over the years, researchers have explored plenty of approaches and avenues to improve cancer management. One notable strategy includes the study of extracellular vesicles (EVs) as potential biomarkers and therapeutics. Among these EVs, exosomes have emerged as particularly promising candidates due to their unique characteristic properties and functions. They are small membrane-bound vesicles secreted by cells carrying a cargo of biomolecules such as proteins, nucleic acids, and lipids. These vesicles play crucial roles in intercellular communication, facilitating the transfer of biological information between cell-to-cell communication. Exosomes transport cargoes such as DNA, RNA, proteins, and lipids involved in cellular reprogramming and promoting cancer. In this review, we explore the molecular composition of exosomes, significance of exosomes chemistry in cancer development, and its theranostic application as well as exosomes research complications and solutions.

Establishment and characterisation of a novel canine mast cell tumour cell line (C18)

BACKGROUND

Mast cell tumour (MCT) is a life-threatening neoplasm commonly found in dogs worldwide. The outcome of treatment for dogs with cutaneous MCT is currently poor, mainly because of the tumour's aggressiveness and the heterogeneity in tumour behaviour. This study established a novel canine MCT cell line and compared with three reference canine MCT cell lines (CMMC, VIMC and CoMS) in terms of their characteristics and tumour sensitivity to immune cell-mediated cytotoxicity.

RESULTS

Of 18 MCT samples, only one cell line derived from high grade cutaneous MCT was established and referred to as C18 cell line. The C18 cell line could be maintained for over 100 passages while they still exhibited c-kit, tryptase, FcεRIα and FcεRIβ expression. The C18 had the longest doubling time and smallest tumour spheroid size when compared to the other three reference cell lines. The C18 also had c-kit internal tandem duplication (ITD) in exon 11 and nine single nucleotide polymorphisms (SNPs) in five genes, namely c-kit, HYAL4, SEL1L, SPAM1 and TRAF3. For a comparison of tumour sensitivity to immune cell-mediated cytotoxicity, the percentages of early and total apoptotic cells were significantly increased in all four cell lines. However, the percentages of viable cells were significantly decreased only in C18.

CONCLUSION

In conclusion, a novel canine cutaneous MCT cell line was successfully established, in terms of its characteristics, growth behavior and interaction with PBMCs. The C18 cell line holds a potential promise for advancing studies and developing new therapeutic strategies.

The use of a multi-metric readout screen to identify EHMT2/G9a-inhibition as a modulator of cancer-associated fibroblast activation state

Cancer-associated fibroblasts (CAFs) play a pivotal role in cancer progression, including mediating tumour cell invasion via their pro-invasive secretory profile and ability to remodel the extracellular matrix (ECM). Given that reduced CAF abundance in tumours correlates with improved outcomes in various cancers, we set out to identify epigenetic targets involved in CAF activation in regions of tumour-stromal mixing with the goal of reducing tumour aggressiveness. Using the GLAnCE (Gels for Live Analysis of Compartmentalized Environments) platform, we performed an image-based, phenotypic screen that enabled us to identify modulators of CAF abundance and the capacity of CAFs to induce tumour cell invasion. We identified EHMT2 (also known as G9a), an enzyme that targets the methylation of histone 3 lysine 9 (H3K9), as a potent modulator of CAF abundance and CAF-mediated tumour cell invasion. Transcriptomic and functional analysis of EHMT2-inhibited CAFs revealed EHMT2 participated in driving CAFs towards a pro-invasive phenotype and mediated CAF hyperproliferation, a feature typically associated with activated fibroblasts in tumours. Our study suggests that EHMT2 regulates CAF state within the tumour microenvironment by impacting CAF activation, as well as by magnifying the pro-invasive effects of these activated CAFs on tumour cell invasion through promoting CAF hyperproliferation.

An innovative strategy harnessing self-activating CAR-NK cells to mitigate TGF-β1-driven immune suppression

The dysfunction of natural killer (NK) cells, mediated by transforming growth factor β1 (TGFβ1) within the tumor microenvironment, impedes antitumor therapy and contributes to poor clinical outcomes. Our study introduces self-activating chimeric antigen receptor (CAR)-NK cells that block TGFβ1 signaling by releasing a specifically designed peptide, P6, which targets mesothelin in pancreatic tumors. P6 originates from the interaction sites between TGFβ1 and TGFβ receptor 1 and effectively disrupts TGFβ1's inhibitory signaling in NK cells. Our analysis demonstrates that P6 treatment interrupts the SMAD2/3 pathway in NK cells, mitigating TGFβ1-mediated suppression of NK cell activity, thereby enhancing their metabolic function and cytotoxic response against pancreatic tumors. These CAR-NK cells exhibit potent antitumor capabilities, as evidenced in spheroid cultures with cancer-associated fibroblasts and in vivo mouse models. Our approach marks a substantial advancement in overcoming TGFβ1-mediated immune evasion, offering a promising avenue for revolutionizing cancer immunotherapy.

The uptake of extracellular vesicles: Research progress in cancer drug resistance and beyond

Extracellular vesicles (EVs) are heterogeneous vesicles released by donor cells that can be taken up by recipient cells, thus inducing cellular phenotype changes. Since their discovery decades ago, roles of EVs in modulating initiation, growth, survival and metastasis of cancer have been revealed. Recent studies from multifaceted perspectives have further detailed the contribution of EVs to cancer drug resistance; however, the role of EV uptake in conferring drug resistance seems to be overlooked. In this comprehensive review, we update the EV subtypes and approaches for determining EV uptake. The biological basis of EV uptake is systematically summarized. Moreover, we focus on the diverse uptake mechanisms by which EVs carry out the intracellular delivery of functional molecules and drug resistance signaling. Furthermore, we highlight how EV uptake confers drug resistance and identify potential strategies for targeting EV uptake to overcome drug resistance. Finally, we discuss the research gap on the role of EV uptake in promoting drug resistance. This updated knowledge provides a new avenue to overcome cancer drug resistance by targeting EV uptake.

Hypoxia-induced histone methylation and NF-κB activation in pancreas cancer fibroblasts promote EMT-supportive growth factor secretion

The pancreatic ductal adenocarcinoma (PDAC) tumor microenvironment contains hypoxic tissue subdomains and cancer-associated fibroblasts (CAFs) of multiple subtypes that play tumor-promoting and -restraining roles. Here, we demonstrate that hypoxia promotes an inflammatory-like CAF phenotype and that hypoxic CAFs selectively promote epithelial-mesenchymal transition (EMT) in PDAC cancer cells through growth factor-mediated cell crosstalk. By analyzing patient tumor single-cell transcriptomics and conducting an inhibitor screen, we identified IGF-2 and HGF as specific EMT-inducing growth factors produced by hypoxic CAFs. We further found that reactive oxygen species-activated NF-κB cooperates with hypoxia-dependent histone methylation to promote IGF-2 and HGF expression in hypoxic CAFs. In lineage-traced autochthonous PDAC mouse tumors, hypoxic CAFs resided preferentially near hypoxic, mesenchymal cancer cells. However, in subcutaneous tumors engineered with hypoxia fate-mapped CAFs, once-hypoxic re-oxygenated CAFs lacked a spatial correlation with mesenchymal cancer cells. Thus, hypoxia promotes reversible CAF-malignant cell interactions that drive EMT through druggable signaling pathways.

One-sentence summary

We show that hypoxic fibroblasts in pancreas cancer leverage histone methylation and ROS-mediated NF-κB activation to produce growth factors that drive epithelial-mesenchymal transition in malignant cells, demonstrating how tumor stromal features cooperate to initiate a signaling process for disease progression.

Exosomal signaling in gynecologic cancer development: The role of cancer-associated fibroblasts

Gynecologic cancer, a prevalent and debilitating disease affecting women worldwide, is characterized by the uncontrolled proliferation of cells in the reproductive organs. The complex etiology of gynecologic cancer encompasses multiple subtypes, including cervical, ovarian, uterine, vaginal, and vulvar cancers. Despite optimal treatment strategies, which typically involve cytoreductive surgery and platinum-based chemotherapy, gynecologic cancer frequently exhibits recalcitrant relapse and poor prognosis. Recent studies have underscored the significance of the tumor microenvironment in ovarian carcinogenesis, particularly with regards to the discovery of aberrant genomic, transcriptomic, and proteomic profiles. Within this context, cancer-associated fibroblasts (CAFs) emerge as a crucial component of the stromal cell population, playing a pivotal role in oncogenesis and cancer progression. CAF-derived exosomes, small extracellular vesicles capable of conveying biological information between cells, have been implicated in a range of tumor-related processes, including tumorigenesis, cell proliferation, metastasis, drug resistance, and immune responses. Furthermore, aberrant expression of CAF-derived exosomal noncoding RNAs and proteins has been found to strongly correlate with clinical and pathological characteristics of gynecologic cancer patients. Our review provides a novel perspective on the role of CAF-derived exosomes in gynecologic cancer, highlighting their potential as diagnostic biomarkers and therapeutic targets.

Neural Network-Enabled Multiparametric Impedance Signal Templating for High throughput Single-Cell Deformability Cytometry Under Viscoelastic Extensional Flows

Cellular biophysical metrics exhibit systematic alterations during processes, such as metastasis and immune cell activation, which can be used to identify and separate live cell subpopulations for targeting drug screening. Image-based biophysical cytometry under extensional flows can accurately quantify cell deformability based on cell shape alterations but needs extensive image reconstruction, which limits its inline utilization to activate cell sorting. Impedance cytometry can measure these cell shape alterations based on electric field screening, while its frequency response offers functional information on cell viability and interior structure, which are difficult to discern by imaging. Furthermore, 1-D temporal impedance signal trains exhibit characteristic shapes that can be rapidly templated in near real-time to extract single-cell biophysical metrics to activate sorting. We present a multilayer perceptron neural network signal templating approach that utilizes raw impedance signals from cells under extensional flow, alongside its training with image metrics from corresponding cells to derive net electrical anisotropy metrics that quantify cell deformability over wide anisotropy ranges and with minimal errors from cell size distributions. Deformability and electrical physiology metrics are applied in conjunction on the same cell for multiparametric classification of live pancreatic cancer cells versus cancer associated fibroblasts using the support vector machine model.

MicroRNAs in pancreatic cancer drug resistance: mechanisms and therapeutic potential

Pancreatic cancer (PC) remains one of the most lethal malignancies, primarily due to its intrinsic resistance to conventional therapies. MicroRNAs (miRNAs), key regulators of gene expression, have been identified as crucial modulators of drug resistance mechanisms in this cancer type. This review synthesizes recent advancements in our understanding of how miRNAs influence treatment efficacy in PC. We have thoroughly summarized and discussed the complex role of miRNA in mediating drug resistance in PC treatment. By highlighting specific miRNAs that are implicated in drug resistance pathways, we provide insights into their functional mechanisms and interactions with key molecular targets. We also explore the potential of miRNA-based strategies as novel therapeutic approaches and diagnostic tools to overcome resistance and improve patient outcomes. Despite promising developments, challenges such as specificity, stability, and effective delivery of miRNA-based therapeutics remain. This review aims to offer a critical perspective on current research and propose future directions for leveraging miRNA-based interventions in the fight against PC.

A stumbling block in pancreatic cancer treatment: drug resistance signaling networks

The primary node molecules in the cell signaling network in cancer tissues are maladjusted and mutated in comparison to normal tissues, which promotes the occurrence and progression of cancer. Pancreatic cancer (PC) is a highly fatal cancer with increasing incidence and low five-year survival rates. Currently, there are several therapies that target cell signaling networks in PC. However, PC is a "cold tumor" with a unique immunosuppressive tumor microenvironment (poor effector T cell infiltration, low antigen specificity), and targeting a single gene or pathway is basically ineffective in clinical practice. Targeted matrix therapy, targeted metabolic therapy, targeted mutant gene therapy, immunosuppressive therapy, cancer vaccines, and other emerging therapies have shown great therapeutic potential, but results have been disappointing. Therefore, we summarize the identified and potential drug-resistant cell signaling networks aimed at overcoming barriers to existing PC therapies.

Exosome applications for the diagnosis and treatment of pancreatic ductal adenocarcinoma: An update (Review)

Pancreatic ductal adenocarcinoma (PDAC) is a malignant neoplasm that typically manifests with subtle clinical manifestations in its early stages and frequently eludes diagnosis until the advanced phases of the disease. The limited therapeutic options available for PDAC significantly contribute to its high mortality rate, highlighting the urgent need for novel biomarkers capable of effectively identifying early clinical manifestations and facilitating precise diagnosis. The pivotal role of cellular exosomes in both the pathogenesis and therapeutic interventions for PDAC has been underscored. Furthermore, researchers have acknowledged the potential of exosomes as targeted drug carriers against regulatory cells in treating PDAC. The present article aims to provide a comprehensive review encompassing recent advancements in utilizing exosomes for elucidating mechanisms underlying disease development, patterns of metastasis, diagnostic techniques and treatment strategies associated with PDAC.

Cancer-Associated Fibroblast-Secreted Exosomes Regulate Macrophage Polarization in Pancreatic Cancer via the NOD1 Pathway

Metastasis is a major cause of poor prognosis of pancreatic cancer. Exosomes (Exos) regulate cancer progression by modulating macrophage polarization. This study aimed to investigate the effects of cancer-associated fibroblast (CAF)-released Exos on macrophage polarization in pancreatic cancer and the molecular mechanisms. THP-1 cells or xenografted tumor mice were treated with Exos from CAFs, and macrophage polarization was analyzed using quantitative real-time PCR (qPCR) and flow cytometry. THP-1 cells were cocultured with BXPC-3 cells, and metastasis was analyzed using Transwell assay and scratch test. Exosomal PTGS2 was detected using qPCR, and the NOD1 pathway was evaluated using western blot analysis. The results showed that Exos promoted M2-type polarization and inhibited M1-type polarization, and then facilitated pancreatic cancer cell migration, invasion, and epithelial-mesenchymal transition. PTGS2 expression was increased in Exo-treated macrophages, and its knockdown in CAFs facilitated M2 to M1 macrophage polarization. Moreover, Exos promoted the NOD1 pathway via PTGS2, and inhibition of NOD1 reversed the polarization caused by Exos. Additionally, NOD1 was required in M1/M2 polarization in vivo mediated by Exos. In conclusion, CAF-secreted Exos facilitated M2 macrophage polarization by carrying PTGS2 to activate the NOD1 pathway, thereby promoting pancreatic cancer metastasis, providing evidence that CAF-Exos accelerating pancreatic cancer progression.

Cancer-associated fibroblasts, tumor and radiotherapy: interactions in the tumor micro-environment

Cancer-associated fibroblasts (CAFs) represent a group of genotypically non-malignant stromal cells in the tumor micro-environment (TME) of solid tumors that encompasses up to 80% of the tumor volume. Even though the phenotypic diversity and plasticity of CAFs complicates research, it is well-established that CAFs can affect many aspects of tumor progression, including growth, invasion and therapy resistance. Although anti-tumorigenic properties of CAFs have been reported, the majority of research demonstrates a pro-tumorigenic role for CAFs via (in)direct signaling to cancer cells, immunomodulation and extracellular matrix (ECM) remodeling. Following harsh therapeutic approaches such as radio- and/or chemotherapy, CAFs do not die but rather become senescent. Upon conversion towards senescence, many pro-tumorigenic characteristics of CAFs are preserved or even amplified. Senescent CAFs continue to promote tumor cell therapy resistance, modulate the ECM, stimulate epithelial-to-mesenchymal transition (EMT) and induce immunosuppression. Consequently, CAFs play a significant role in tumor cell survival, relapse and potentially malignant transformation of surviving cancer cells following therapy. Modulating CAF functioning in the TME therefore is a critical area of research. Proposed strategies to enhance therapeutic efficacy include reverting senescent CAFs towards a quiescent phenotype or selectively targeting (non-)senescent CAFs. In this review, we discuss CAF functioning in the TME before and during therapy, with a strong focus on radiotherapy. In the future, CAF functioning in the therapeutic TME should be taken into account when designing treatment plans and new therapeutic approaches.

A spheroid whole mount drug testing pipeline with machine-learning based image analysis identifies cell-type specific differences in drug efficacy on a single-cell level

BACKGROUND

The growth and drug response of tumors are influenced by their stromal composition, both in vivo and 3D-cell culture models. Cell-type inherent features as well as mutual relationships between the different cell types in a tumor might affect drug susceptibility of the tumor as a whole and/or of its cell populations. However, a lack of single-cell procedures with sufficient detail has hampered the automated observation of cell-type-specific effects in three-dimensional stroma-tumor cell co-cultures.

METHODS

Here, we developed a high-content pipeline ranging from the setup of novel tumor-fibroblast spheroid co-cultures over optical tissue clearing, whole mount staining, and 3D confocal microscopy to optimized 3D-image segmentation and a 3D-deep-learning model to automate the analysis of a range of cell-type-specific processes, such as cell proliferation, apoptosis, necrosis, drug susceptibility, nuclear morphology, and cell density.

RESULTS

This demonstrated that co-cultures of KP-4 tumor cells with CCD-1137Sk fibroblasts exhibited a growth advantage compared to tumor cell mono-cultures, resulting in higher cell counts following cytostatic treatments with paclitaxel and doxorubicin. However, cell-type-specific single-cell analysis revealed that this apparent benefit of co-cultures was due to a higher resilience of fibroblasts against the drugs and did not indicate a higher drug resistance of the KP-4 cancer cells during co-culture. Conversely, cancer cells were partially even more susceptible in the presence of fibroblasts than in mono-cultures.

CONCLUSION

In summary, this underlines that a novel cell-type-specific single-cell analysis method can reveal critical insights regarding the mechanism of action of drug substances in three-dimensional cell culture models.

Exploring the dual role of endoplasmic reticulum stress in urological cancers: Implications for tumor progression and cell death interactions

The endoplasmic reticulum (ER) is crucial for maintaining calcium balance, lipid biosynthesis, and protein folding. Disruptions in ER homeostasis, often due to the accumulation of misfolded or unfolded proteins, lead to ER stress, which plays a significant role in various diseases, especially cancer. Urological cancers, which account for high male mortality worldwide, pose a persistent challenge due to their incurability and tendency to develop drug resistance. Among the numerous dysregulated biological mechanisms, ER stress is a key factor in the progression and treatment response of these cancers. This review highlights the dual role of aberrant ER stress activation in urologic cancers, affecting both tumor growth and therapeutic outcomes. While ER stress can support tumor growth through pro-survival autophagy, it primarily inhibits cancer progression via apoptosis and pro-death autophagy. Interestingly, ER stress can paradoxically aid cancer progression through mechanisms such as exosome-mediated immune evasion. Additionally, the review examines how pharmacological interventions, particularly with phytochemicals, can stimulate ER stress-mediated tumor suppression. Key regulators, including PERK, IRE1α, and ATF6, are discussed for their roles in upregulating CHOP levels and triggering apoptosis. In conclusion, a deeper understanding of ER stress in urological cancers not only clarifies the complex interactions between cellular stress and cancer progression but also provides new opportunities for innovative therapeutic strategies.

Extracellular vesicles in cancers: mechanisms, biomarkers, and therapeutic strategies

Extracellular vesicles (EVs) composed of various biologically active constituents, such as proteins, nucleic acids, lipids, and metabolites, have emerged as a noteworthy mode of intercellular communication. There are several categories of EVs, including exosomes, microvesicles, and apoptotic bodies, which largely differ in their mechanisms of formation and secretion. The amount of evidence indicated that changes in the EV quantity and composition play a role in multiple aspects of cancer development, such as the transfer of oncogenic signals, angiogenesis, metabolism remodeling, and immunosuppressive effects. As EV isolation technology and characteristics recognition improve, EVs are becoming more commonly used in the early diagnosis and evaluation of treatment effectiveness for cancers. Actually, EVs have sparked clinical interest in their potential use as delivery vehicles or vaccines for innovative antitumor techniques. This review will focus on the function of biological molecules contained in EVs linked to cancer progression and their participation in the intricate interrelationship within the tumor microenvironment. Furthermore, the potential efficacy of an EV-based liquid biopsy and delivery cargo for treatment will be explored. Finally, we explicitly delineate the limitations of EV-based anticancer therapies and provide an overview of the clinical trials aimed at improving EV development.

OSCC-derived EVs educate fibroblasts and remodel collagen landscape

Cancer-associated myofibroblasts (mCAFs) represent a significant component of the tumor microenvironment due to their contributions to extracellular matrix (ECM) remodeling. The pro-tumor mechanisms of extracellular vesicles (EVs) by regulating mCAFs and related collagens remain poorly understood in oral squamous cell carcinoma (OSCC). In this study, through analysis of single-cell sequencing data and immunofluorescence staining, we confirmed the increased presence of mCAFs and enrichment of specific collagen types in OSCC tissues. Furthermore, we demonstrated that OSCC-derived EVs promote the transformation of fibroblasts into mCAFs, leading to tumor invasion. Proteomic analysis identified the presence of TGF-β1 in EVs and revealed its role in inducing mCAFs via the TGF-β1/SMAD signaling pathway. Experiments in vivo confirmed that EVs, particularly those carrying TGF-β1, trigger COL18high COL5high matrix deposition, thereby forming the pro-tumor ECM in OSCC. In summary, our investigation unveils the significant involvement of OSCC-derived EVs in orchestrating the differentiation of fibroblasts into mCAFs and modulating specific collagen types within the ECM. Therefore, this study provides a theoretical basis for targeting the EV-mediated TGF-β1 signaling pathway as a potential therapeutic strategy for OSCC.

Mechanism of bone-marrow mesenchymal stem cell-derived exosomes mediating microRNA-139-5p to regulate β-catenin in the modulation of proliferation and apoptosis of acute myeloid leukemia cells

OBJECTIVE

Acute myeloid leukemia (AML) stands out as a malignancy of the stem cell precursors of the myeloid lineage. Bone-marrow mesenchymal stem cell-derived exosomes (BMSC-exos) affect AML progression. We explored the effects and mechanism of BMSC-exos on AML cell proliferation and apoptosis.

METHODS

Human AML cells (MOLM-16, MV-4-11) and normal human hematopoietic cells (GM12878) cultured in vitro were treated with exos extracted from BMSCs that transfected with microRNA (miR)-139-5p-mimics, ovβ-catenin, or miR-139-5p-inhibitor. BMSC morphology was observed by a microscopy, and its adipogenic and osteogenic differentiation abilities were assessed by oil red O staining and alizarin red S staining. BMSC-exos were extracted by ultracentrifugation, and their morphology was observed by a transmission electron microscopy. BMSC-exos were identified by nanoparticle tracking analysis and Western blot. The binding sites between miR-139-5p and β-catenin were predicted by TargetScan database, and then validated by dual-luciferase reporter assay. mRNA levels of miR-139-5p and β-catenin, cell proliferation, and apoptosis were evaluated by RT-qPCR, CCK-8, and flow cytometry. The expressions of CD63, CD81, TSG101, and GRP94 and the proteins of β-catenin, Bax, and Bcl-2 were determined by Western blot.

RESULTS

miR-139-5p was poorly expressed in AML cell lines. miR-139-5p overexpression reduced AML cell viability/proliferation/Bcl-2 level, and raised apoptosis/Bax level. BMSC-exos repressed AML cell proliferation and promoted apoptosis via miR-139-5p. miR-139-5p targeted to inhibit β-catenin expression. Subsequently, up-regulated β-catenin partially counteracted the effects of miR-139-5p in BMSC-exos on AML cell proliferation and apoptosis.

CONCLUSION

BMSC-exos targeted to repress β-catenin expression by miR-139-5p, limited AML cell proliferation and facilitated apoptosis.

Hydrogel models of pancreatic adenocarcinoma to study cell mechanosensing

Pancreatic adenocarcinoma (PDAC) is the predominant form of pancreatic cancer and one of the leading causes of cancer-related death worldwide, with an extremely poor prognosis after diagnosis. High mortality from PDAC arises partly due to late diagnosis resulting from a lack of early-stage biomarkers and due to chemotherapeutic drug resistance, which arises from a highly fibrotic stromal response known as desmoplasia. Desmoplasia alters tissue mechanics, which triggers changes in cell mechanosensing and leads to dysregulated transcriptional activity and disease phenotypes. Hydrogels are effective in vitro models to mimic mechanical changes in tissue mechanics during PDAC progression and to study the influence of these changes on mechanosensitive cell responses. Despite the complex biophysical changes that occur within the PDAC microenvironment, carefully designed hydrogels can very closely recapitulate these properties during PDAC progression. Hydrogels are relatively inexpensive, highly reproducible and can be designed in a humanised manner to increase their relevance for human PDAC studies. In vivo models have some limitations, including species-species differences, high variability, expense and legal/ethical considerations, which make hydrogel models a promising alternative. Here, we comprehensively review recent advancements in hydrogel bioengineering for developing our fundamental understanding of mechanobiology in PDAC, which is critical for informing advanced therapeutics.

Cancer-associated fibroblasts maintain critical pancreatic cancer cell lipid homeostasis in the tumor microenvironment

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with abundant cancer-associated fibroblasts (CAFs) creating hallmark desmoplasia that limits oxygen and nutrient delivery. This study explores the importance of lipid homeostasis under stress. Exogenous unsaturated lipids, rather than de novo synthesis, sustain PDAC cell viability by relieving endoplasmic reticulum (ER) stress under nutrient scarcity. Furthermore, CAFs are less hypoxic than adjacent malignant cells in vivo, nominating them as a potential source of unsaturated lipids. CAF-conditioned medium promotes PDAC cell survival upon nutrient and oxygen deprivation, an effect reversed by delipidation. Lysophosphatidylcholines (LPCs) are particularly enriched in CAF-conditioned medium and preferentially taken up by PDAC cells, where they are converted to phosphatidylcholine (PC) to sustain membrane integrity. Blocking LPC-to-PC conversion inhibits PDAC cell survival and increases ER stress. These findings show a critical lipid "cross-feeding" mechanism that promotes PDAC cell survival, offering a potential metabolic target for treatment.

Exploring the role of antigen-presenting cancer-associated fibroblasts and CD74 on the pancreatic ductal adenocarcinoma tumor microenvironment

Pancreatic ductal adenocarcinoma (PDAC) has proven to be a formidable cancer primarily due to its tumor microenvironment (TME). This highly desmoplastic, hypoxic, and pro-inflammatory environment has not only been shown to facilitate the growth and metastasis of PDAC but has also displayed powerful immunosuppressive capabilities. A critical cell involved in the development of the PDAC TME is the fibroblast, specifically the antigen-presenting cancer-associated fibroblast (apCAF). The pro-inflammatory environment of PDAC induces the proliferation of apCAFs, promoting immunosuppression through immune cell inactivation, immune response regulation, and expression of CD74. In conjunction with apCAFs and tumor cells, CD74 serves as a versatile promoter of PDAC by preventing tumor antigen-expression on tumor cells, upregulating the expression of immunosuppressive chemical mediators, and activating proliferative pathways to induce PDAC malignancy. This review will highlight critical mediators and pathways that promote the PDAC stroma and TME with its hypoxic and immunosuppressive properties. Further, we will highlight the nature of apCAFs and CD74, their specific roles in the PDAC TME, and their potential as targets for immunotherapy.

Recent Advances of Small Extracellular Vesicles for the Regulation and Function of Cancer-Associated Fibroblasts

Cancer-associated fibroblasts (CAFs) are a heterogeneous cell population in the tumor microenvironment (TME) that critically affect cancer progression. Small extracellular vesicles (sEVs) act as information messengers by transmitting a wide spectrum of biological molecules, including proteins, nucleic acids, and metabolites, from donor cells to recipient cells. Previous studies have demonstrated that CAFs play important roles in tumor progression by regulating tumor cell proliferation, metastasis, therapeutic resistance, and metabolism via sEVs. In turn, tumor-derived sEVs can also regulate the activation and phenotype switch of CAFs. The dynamic crosstalk between CAFs and cancer cells via sEVs could ultimately determine cancer progression. In this review, we summarized the recent advance of the biological roles and underlying mechanisms of sEVs in mediating CAF-tumor cell interaction and its impact on cancer progression. We also reviewed the clinical applications of tumor- and CAF-derived sEVs, which could identify novel potential targets and biomarkers for cancer diagnosis, therapy, and prognosis.

The role and clinical applications of exosomes in cancer drug resistance

Tumor-secreted exosomes are heterogeneous multi-signal messengers that support cancer growth and dissemination by mediating intercellular crosstalk and activating signaling pathways. Distinct from previous reviews, we focus intently on exosome-therapeutic resistance dynamics and summarize the new findings about the regulation of cancer treatment resistance by exosomes, shedding light on the complex processes via which these nanovesicles facilitate therapeutic refractoriness across various malignancies. Future research in exosome biology can potentially transform diagnostic paradigms and therapeutic interventions for cancer management. This review synthesizes recent insights into the exosome-driven regulation of cancer drug resistance, illuminates the sophisticated mechanisms by which these nanovesicles facilitate therapeutic refractoriness across various malignancies, and summarizes some strategies to overcome drug resistance.

TGF-β Signaling Loop in Pancreatic Ductal Adenocarcinoma Activates Fibroblasts and Increases Tumor Cell Aggressiveness

BACKGROUND

The interaction between cancer cells and cancer-associated fibroblasts (CAFs) is a key determinant of the rapid progression, high invasiveness, and chemoresistance of aggressive desmoplastic cancers such as pancreatic ductal adenocarcinoma (PDAC). Tumor cells are known to reprogram fibroblasts into CAFs by secreting transforming growth factor beta (TGF-β), amongst other cytokines. In turn, CAFs produce soluble factors that promote tumor-cell invasiveness and chemoresistance, including TGF-β itself, which has a major role in myofibroblastic CAFs. Such a high level of complexity has hampered progress toward a clear view of the TGFβ signaling loop between stromal fibroblasts and PDAC cells.

METHODS

Here, we tackled this issue by using co-culture settings that allow paracrine signaling alone (transwell systems) or paracrine and contact-mediated signaling (3D spheroids).

RESULTS

We found that TGF-β is critically involved in the activation of normal human fibroblasts into alpha-smooth muscle actin (α-SMA)-positive CAFs. The TGF-β released by CAFs accounted for the enhanced proliferation and resistance to gemcitabine of PDAC cells. This was accompanied by a partial epithelial-to-mesenchymal transition in PDAC cells, with no increase in their migratory abilities. Nevertheless, 3D heterospheroids comprising PDAC cells and fibroblasts allowed monitoring the pro-invasive effects of CAFs on cancer cells, possibly due to combined paracrine and physical contact-mediated signals.

CONCLUSIONS

We conclude that TGF-β is only one of the players that mediates the communication between PDAC cells and fibroblasts and controls the acquisition of aggressive phenotypes. Hence, these advanced in vitro models may be exploited to further investigate these events and to design innovative anti-PDAC therapies.

The emerging role of extracellular vesicles and particles in prostate cancer diagnosis, and risk stratification

Current approaches for prostate cancer (PCa) diagnosis and risk stratification require greater accuracy. Extracellular vesicles and particles (EVPs) containing diverse cargos from parent cells are released into the extracellular microenvironment and play a critical role in intercellular communication. Accumulating evidence demonstrates that EVPs are emerging as a promising focus for the exploration of cancer biomarkers and therapeutic targets. However, the precise categorisation and nomenclature of EVP subpopulations remains challenging due to their compositional complexity, inherent heterogeneity in molecular composition, and structure. The recent identification of two novel non-vesicular extracellular particle subtypes, exomeres and supermeres, has altered our understanding of the distinct subpopulations of EVPs and their roles in biological and physiological processes. Here, we discuss recent advances in the field of EVPs, describe characteristics of EVP subpopulations, focus on the application and potential of EVPs in PCa diagnosis and risk stratification by liquid biopsy, and highlight the major challenges and prospects of EVP research in PCa area.

Interactions between cancer and stroma mediated by extracellular vesicles

Extracellular vehicles (EVs) are small membrane-bound particles that are released by both cancer and stromal cells. These vesicles have emerged as key mediators of intercellular communication within the tumor microenvironment. In particular, EVs have been shown to play a critical role in facilitating the interactions between cancer cells and the surrounding stroma. Through the transfer of various bioactive molecules, including proteins, lipids, and nucleic acids, EVs are able to modulate the behavior of recipient cells and promote tumorigenesis. Additionally, EVs can also contribute to the development of drug resistance and immune evasion, further highlighting their importance in cancer progression. This review will summarize the current knowledge regarding EV-mediated interactions between cancer and stromal cells, and discuss their implications for cancer diagnosis and therapy.

Emerging Trends in Gastrointestinal Cancer Targeted Therapies: Harnessing Tumor Microenvironment, Immune Factors, and Metabolomics Insights

Gastrointestinal (GI) cancers are the leading cause of new cancer cases and cancer-related deaths worldwide. The treatment strategies for patients with GI tumors have focused on oncogenic molecular profiles associated with tumor cells. Recent evidence has demonstrated that the tumor cell functions are modulated by its microenvironment, compromising fibroblasts, extracellular matrices, microbiome, immune cells, and the enteric nervous system. Along with the tumor microenvironment components, alterations in key metabolic pathways have emerged as a hallmark of tumor cells. From these perspectives, this review will highlight the functions of different cellular components of the GI tumor microenvironment and their implications for treatment. Furthermore, we discuss the major metabolic reprogramming in GI tumor cells and how understanding metabolic rewiring could lead to new therapeutic strategies. Finally, we briefly summarize the targeted agents currently being studied in GI cancers. Understanding the complex interplay between tumor cell-intrinsic and -extrinsic factors during tumor progression is critical for developing new therapeutic strategies.

Construction of a prognostic model with exosome biogenesis- and release-related genes and identification of RAB27B in immune infiltration of pancreatic cancer

Background

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive and fatal disease. Exosomes are extracellular vesicles that plays a vital rule in the progression and metastasis of PDAC. However, the specific mechanism of exosome biogenesis and release in the tumorigenesis and development of pancreatic cancer remains elusive. The aim of this study is to develop novel biomarkers and construct a reliable prognostic signature to accurately stratify patients and optimize clinical decision-making.

Methods

Gene expression and clinical data were acquired from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Univariate Cox regression analysis, random forest analysis, least absolute shrinkage and selection operator (LASSO) regression analysis, and multivariate Cox regression analysis were used to construct the risk signature. The effectiveness of the model was validated by survival point plot, Kaplan-Meier survival analysis, and receiver operating characteristic (ROC) curve in training, testing and entire cohorts. Meanwhile, single sample gene set enrichment analysis (ssGSEA), ESTIMATE and CIBERSORT algorithm were utilized to assess the association of the risk signature with the immune status in the PDAC tumor microenvironment. We also performed functional enrichment, tumor mutation analysis, and DNA methylation analyses based on the risk signature. The function of the core gene was further verified by polymerase chain reaction (PCR), western blot, bicinchoninic acid (BCA), immunohistochemistry (IHC) and in vitro experiments including cell proliferation, migration, and apoptosis experiments.

Results

We constructed an exosome biogenesis- and release-related risk model which could serve as an effective and independent prognosis predictor for PDAC patients. The immune infiltration analysis revealed that our signature was related to the PDAC immune microenvironment, mainly associated with a lower proportion of natural killer (NK) cells and CD8+ T cells. Tissue microarray IHC confirmed the association of RAB27B with poor prognosis in PDAC. Knockdown of RAB27B expression promoted PDAC cells' apoptosis, while decreased cellular proliferation and migration. Also, knockdown of RAB27B expression led to reduced exosome secretion, while RAB27B overexpression promoted exosome secretion.

Conclusions

The predictive signature can predict overall survival, help elucidate the mechanism of exosome biogenesis and release, and provide immunotherapy guidance for PDAC patients.

Cancer-associated fibroblast-derived exosome Leptin promotes malignant biological lineage in pancreatic ductal adenocarcinoma by regulating ABL2 via miR-224-3p

BACKGROUND

Cancer-associated fibroblasts, as a major component of the tumor microenvironment, have been shown to exhibit protumorigenic effects in pancreatic ductal adenocarcinoma. Moreover, cancer-associated fibroblasts-derived exosomes have been reported to promote tumor development, but exact mechanisms have not been elucidated. The purpose of this study was to investigate the processes by which exosomes generated from cancer-associated fibroblasts promote tumor growth.

METHODS

twenty-one patients with pancreatic ductal adenocarcinoma who evaluated preoperatively as potentially surgically resectable without distant metastasis and pathologically examined postoperatively as pancreatic ductal cell carcinoma were included. We determined the expression of Leptin as well as downstream proteins at the clinical and cellular levels. Cancer-associated fibroblast-derived exosomes were characterised by nanoparticle transmission electron microscopy and tracking analysis. To ascertain the mechanism mediating the action of exosomal Leptin in pancreatic ductal adenocarcinoma, we performed CCK-8 assay, colony formation assays, transwell and wound healing assays in PSN1 cells to evaluate cell proliferation, migration and invasion. Western blotting was used to detect the level of Leptin, ABL2 and exosome markers. qRT-PCR was employed to evaluate miR-224-3p. Cancer-associated fibroblasts markers and exosome uptake were verified by immunofluorescence.

RESULTS

Western blotting assays show that Leptin is present inside tissues and cancer-associated fibroblasts in pancreatic ductal adenocarcinoma. Cancer-associated fibroblasts stimulated PSN1 cells growth, migration and invasion in vitro by secreting the exosomal Leptin. Exosomal Leptin could regulate miR-224-3p, which targets negative regulation of ABL2. Inhibiting Leptin significantly limited PSN1 cells growth, migration and invasion. In vitro analyses revealed that miR-224-3p mimics mitigate the inhibitory effect of cancer-associated fibroblasts knockdown of Leptin on PSN1 cells development, but overexpression of ABL2 partly abolished the tumor-promoting phenotype of miR-224-3p mimics.

CONCLUSION

Our results revealed that cancer-associated fibroblasts mediate pancreatic ductal adenocarcinoma development by regulating the miR-224-3p/ABL2 molecular axis through the secretion of the exosomal Leptin.

SNAI2 as a Prognostic Biomarker Based on Cancer-Associated Fibroblasts in Patients With Lung Adenocarcinoma

Background

Lung adenocarcinoma (LUAD) is a common type of malignant tumor with therapeutic challenges. Cancer-associated fibroblasts (CAFs) promote LUAD growth and metastasis, regulate the tumor immune response, and influence tumor treatment responses and drug resistance. However, the molecular mechanisms through which CAFs control LUAD progression are largely unknown. In this study, we aimed to determine the correlations between CAF-related genes and overall survival (OS) in patients with LUAD.

Methods

We acquired the gene expression data and clinical information of 522 patients with LUAD patients from The Cancer Genome Atlas (TCGA) and 442 patients with LUAD from the Gene Expression Omnibus (GEO) databases. CAF infiltration levels were assessed using the Microenvironment Cell Population (MCP) counter, the Estimating the Proportions of Immune and Cancer cells (EPIC) algorithm, and Tumor Immune Dysfunction and Exclusion (TIDE) scores. A CAF-related gene network was constructed using the Weighted gene co-expression network analysis (WGCNA). Based on the CAF-related genes, univariate Cox regression and Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression analyses were performed to identify prognostic genes. Gene expression levels within the prognostic model were validated using the Cancer Cell Line Encyclopedia (CCLE) databases and Western blotting.

Results

Our results demonstrated that high CAF scores were associated with lower survival rates in patients with LUAD. Gene modules that were highly correlated with high CAF scores were closely associated with tissue characteristics and extracellular matrix structures in LUAD. In addition, correlations between CAF scores and responses to immunotherapy and chemotherapy were observed. Finally, we found that SNAI2 expression was higher in lung cancer tissues than in normal tissues.

Conclusion

Deepening our understanding of the influence of CAFs on tumor progression and treatment response at the molecular level can aid the development of more effective therapeutic strategies. This study provides important insights into the functional mechanisms of action of CAFs in LUAD and highlights their clinical implications.

Cancer therapy resistance mediated by cancer-associated fibroblast-derived extracellular vesicles: biological mechanisms to clinical significance and implications

Cancer-associated fibroblasts (CAFs) are a diverse stromal cell population within the tumour microenvironment, where they play fundamental roles in cancer progression and patient prognosis. Multiple lines of evidence have identified that CAFs are critically involved in shaping the structure and function of the tumour microenvironment with numerous functions in regulating tumour behaviours, such as metastasis, invasion, and epithelial-mesenchymal transition (EMT). CAFs can interact extensively with cancer cells by producing extracellular vesicles (EVs), multiple secreted factors, and metabolites. Notably, CAF-derived EVs have been identified as critical mediators of cancer therapy resistance, and constitute novel therapy targets and biomarkers in cancer management. This review aimed to summarize the biological roles and detailed molecular mechanisms of CAF-derived EVs in mediating cancer resistance to chemotherapy, targeted therapy agents, radiotherapy, and immunotherapy. We also discussed the therapeutic potential of CAF-derived EVs as novel targets and clinical biomarkers in cancer clinical management, thereby providing a novel therapeutic strategy for enhancing cancer therapy efficacy and improving patient prognosis.

Photo-responsive decellularized small intestine submucosa hydrogels

Decellularized small intestine submucosa (dSIS) is a promising biomaterial for promoting tissue regeneration. Isolated from the submucosal layer of animal jejunum, SIS is rich in extracellular matrix (ECM) proteins, including collagen, laminin, and fibronectin. Following mild decellularization, dSIS becomes an acellular matrix that supports cell adhesion, proliferation, and differentiation. Conventional dSIS matrix is usually obtained by thermal crosslinking, which yields a soft scaffold with low stability. To address these challenges, dSIS has been modified with methacrylate groups for photocrosslinking into stable hydrogels. However, dSIS has not been modified with clickable handles for orthogonal crosslinking. Here, we report the development of norbornene-modified dSIS, named dSIS-NB, via reacting amine groups of dSIS with carbic anhydride in acidic aqueous reaction conditions. Using triethylamine (TEA) as a mild base catalyst, we obtained high degrees of NB substitution on dSIS. In addition to describing the synthesis of dSIS-NB, we explored its adaptability in orthogonal hydrogel crosslinking and used dSIS-NB hydrogels for cancer and vascular tissue engineering. Impressively, compared with physically crosslinked dSIS and collagen matrices, orthogonally crosslinked dSIS-NB hydrogels supported rapid dissemination of cancer cells and superior vasculogenic and angiogenic properties. dSIS-NB was also exploited as a versatile bioink for 3D bioprinting applications.

Exosomes: Key Factors in Ovarian Cancer Peritoneal Metastasis and Drug Resistance

Ovarian cancer remains a leading cause of death among gynecological cancers, largely due to its propensity for peritoneal metastasis and the development of drug resistance. This review concentrates on the molecular underpinnings of these two critical challenges. We delve into the role of exosomes, the nano-sized vesicles integral to cellular communication, in orchestrating the complex interactions within the tumor microenvironment that facilitate metastatic spread and thwart therapeutic efforts. Specifically, we explore how exosomes drive peritoneal metastasis by promoting epithelial-mesenchymal transition in peritoneal mesothelial cells, altering the extracellular matrix, and supporting angiogenesis, which collectively enable the dissemination of cancer cells across the peritoneal cavity. Furthermore, we dissect the mechanisms by which exosomes contribute to the emergence of drug resistance, including the sequestration and expulsion of chemotherapeutic agents, the horizontal transfer of drug resistance genes, and the modulation of critical DNA repair and apoptotic pathways. By shedding light on these exosome-mediated processes, we underscore the potential of exosomal pathways as novel therapeutic targets, offering hope for more effective interventions against ovarian cancer's relentless progression.

Multibiomarker panels in liquid biopsy for early detection of pancreatic cancer - a comprehensive review

Pancreatic ductal adenocarcinoma (PDAC) is frequently detected in late stages, which leads to limited therapeutic options and a dismal overall survival rate. To date, no robust method for the detection of early-stage PDAC that can be used for targeted screening approaches is available. Liquid biopsy allows the minimally invasive collection of body fluids (typically peripheral blood) and the subsequent analysis of circulating tumor cells or tumor-associated molecules such as nucleic acids, proteins, or metabolites that may be useful for the early diagnosis of PDAC. Single biomarkers may lack sensitivity and/or specificity to reliably detect PDAC, while combinations of these circulating biomarkers in multimarker panels may improve the sensitivity and specificity of blood test-based diagnosis. In this narrative review, we present an overview of different liquid biopsy biomarkers for the early diagnosis of PDAC and discuss the validity of multimarker panels.

Exosomes That Have Different Cellular Origins Followed by the Impact They Have on Prostate Tumor Development in the Tumor Microenvironment

BACKGROUND

Prostate cancer (PCa) is the most common urinary tumor with the highest incidence rate and the second among the leading causes of death worldwide for adult males. In the worldwide cancer incidence rate, PCa is on the increase. The cancerous cells in the prostate and cells in the microenvironment surrounding the tumor communicate through signal transduction, which is crucial for the development and spread of PCa.

RECENT FINDINGS

Exosomes are nanoscale vesicles released into body fluids by various cells that can aid intercellular communication by releasing nucleic acids and proteins. Exosomes published by different types of cells in the tumor microenvironment can have varying impacts on the proliferation and growth of tumor cells via various signaling pathways, modes of action, and secreted cytokines.

CONCLUSION

The main purpose of this review is to describe the effects of different cell-derived exosomes in the tumor microenvironment of PCa on the progression of tumor cells, as well as to summarize and discuss the prospects for the application of exosomes in the treatment and diagnosis of PCa.

Cancer-Associated Fibroblast-Secreted Exosomes Promote Gastric Cancer Cell Migration and Invasion via the IL-32/ESR1 Axis

Exosomes secreted by cancer-associated fibroblasts (CAFs) play a critical part in cancer progression. This study aimed to explore the effects of CAF-exosomes on gastric cancer (GC) cell metastasis. AGS and HGC-27 cells were treated with exosomes and cell viability, migration, and invasion were evaluated using Cell-Counting Kit-8 and Transwell assays. Exosome-regulated mRNAs were explored using quantitative real-time PCR. The relationship between interleukin (IL)32 and estrogen receptor 1 (ESR1) was evaluated using co-immunoprecipitation and dual-luciferase reporter assays. The results of this study show that CAF-derived exosomes promote GC cell viability, migration, and invasion. Exosome treatment increased the levels of IL32, which interacted with ESR1 and negatively regulated ESR1 levels. Rescue experiments were conducted to demonstrate that CAF-exosomes promoted biological behaviors of GC cells by upregulating IL32 and downregulating ESR1 expression. In conclusion, CAF-derived exosomes promote GC cell viability, migration, and invasion by elevating the IL32/ESR1 axis, suggesting a novel strategy for metastatic GC treatment.

Engineering strategies for apoptotic bodies

Extracellular vesicles (EVs) are lipid bilayer vesicles containing proteins, lipids, nucleic acids, and metabolites secreted by cells under various physiological and pathological conditions that mediate intercellular communication. The main types of EVs include exosomes, microvesicles, and apoptotic bodies (ABs). ABs are vesicles released during the terminal stages of cellular apoptosis, enriched with diverse biological entities and characterized by distinct morphological features. As a result, ABs possess great potential in fields like disease diagnosis, immunotherapy, regenerative therapy, and drug delivery due to their specificity, targeting capacity, and biocompatibility. However, their therapeutic efficacy is notably heterogeneous, and an overdose can lead to side effects such as accumulation in the liver, spleen, lungs, and gastrointestinal system. Through bioengineering, the properties of ABs can be optimized to enhance drug-loading efficiency, targeting precision, and multifunctionality for clinical implementations. This review focuses on strategies such as transfection, sonication, electroporation, surface engineering, and integration with biomaterials to enable ABs to load cargoes and enhance targeting, providing insights into the engineering of ABs.

Structure, unique biological properties, and mechanisms of action of transforming growth factor β

Transforming growth factor β (TGF-β) is a ubiquitous molecule that is extremely conserved structurally and plays a systemic role in human organism. TGF-β is a homodimeric molecule consisting of two subunits joined through a disulphide bond. In mammals, three genes code for TGF-β1, TGF-β2, and TGF-β3 isoforms of this cytokine with a dominating expression of TGF-β1. Virtually, all normal cells contain TGF-β and its specific receptors. Considering the exceptional role of fine balance played by the TGF-β in anumber of physiological and pathological processes in human body, this cytokine may be proposed for use in medicine as an immunosuppressant in transplantology, wound healing and bone repair. TGFb itself is an important target in oncology. Strategies for blocking members of TGF-β signaling pathway as therapeutic targets have been considered. In this review, signalling mechanisms of TGF-β1 action are addressed, and their role in physiology and pathology with main focus on carcinogenesis are described.