Exosomal miR-146a-5p and miR-155-5p promote CXCL12/CXCR7-induced metastasis of colorectal cancer by crosstalk with cancer-associated fibroblasts

Cancer associated fibroblasts and metabolic reprogramming: unraveling the intricate crosstalk in tumor evolution

Metabolic reprogramming provides tumors with an energy source and biofuel to support their survival in the malignant microenvironment. Extensive research into the intrinsic oncogenic mechanisms of the tumor microenvironment (TME) has established that cancer-associated fibroblast (CAFs) and metabolic reprogramming regulates tumor progression through numerous biological activities, including tumor immunosuppression, chronic inflammation, and ecological niche remodeling. Specifically, immunosuppressive TME formation is promoted and mediators released via CAFs and multiple immune cells that collectively support chronic inflammation, thereby inducing pre-metastatic ecological niche formation, and ultimately driving a vicious cycle of tumor proliferation and metastasis. This review comprehensively explores the process of CAFs and metabolic regulation of the dynamic evolution of tumor-adapted TME, with particular focus on the mechanisms by which CAFs promote the formation of an immunosuppressive microenvironment and support metastasis. Existing findings confirm that multiple components of the TME act cooperatively to accelerate the progression of tumor events. The potential applications and challenges of targeted therapies based on CAFs in the clinical setting are further discussed in the context of advancing research related to CAFs.

Exosomal miRNAs: the tumor's trojan horse in selective metastasis

Organs of future metastasis are not passive receivers of circulating tumor cells, but are instead selectively and actively modified by the primary tumor before metastatic spread has even occurred. Tumors orchestrate a pre-metastatic program by conditioning distant organs to create microenvironments that foster the survival and proliferation of tumor cells before their arrival, thereby establishing pre-metastatic niches. Primary tumor-derived exosomes modulate these pre-metastatic niches, generating a permissive environment that facilitates the homing and expansion of tumor cells. Moreover, microRNAs have emerged as a key component of exosomal cargo, serving not only to induce the formation of pre-metastatic niches but also to prime these sites for the arrival and colonization of specific secondary tumor populations. Against this backdrop, this review endeavors to elucidate the impact of tumor-derived exosomal microRNAs on the genesis of their individualized pre-metastatic niches, with a view towards identifying novel means of specifying cancer metastasis and exploiting this phenomenon for cancer immunotherapy.

Targeting the devil: Strategies against cancer-associated fibroblasts in colorectal cancer

Cancer-associated fibroblasts (CAFs), as significant constituents of the tumor microenvironment (TME), play a pivotal role in the progression of cancers, including colorectal cancer (CRC). In this comprehensive review, we presented the origins and activation mechanisms of CAFs in CRC, elaborating on how CAFs drive tumor progression through their interactions with CRC cells, immune cells, vascular endothelial cells, and the extracellular matrix within the TME. We systematically outline the intricate web of interactions among CAFs, tumor cells, and other TME components, and based on this complex interplay, we summarize various therapeutic strategies designed to target CAFs in CRC. It is also essential to recognize that CAFs represent a highly heterogeneous group, encompassing various subtypes such as myofibroblastic CAF (myCAF), inflammatory CAF (iCAF), antigen-presenting CAF (apCAF), vessel-associated CAF (vCAF). Herein, we provide a summary of studies investigating the heterogeneity of CAFs in CRC and the characteristic expression patterns of each subtype. While the majority of CAFs contribute to the exacerbation of CRC malignancy, recent findings have revealed specific subtypes that exert inhibitory effects on CRC progression. Nevertheless, the comprehensive landscape of CAF heterogeneity still awaits exploration. We also highlight pivotal unanswered questions that need to be addressed before CAFs can be recognized as feasible targets for cancer treatment. In conclusion, the aim of our review is to elucidate the significance and challenges of advancing in-depth research on CAFs, while outlining the pathway to uncover the complex roles of CAFs in CRC and underscore their significant potential as therapeutic targets.

Unraveling the MicroRNA tapestry: exploring the molecular dynamics of locoregional recurrent rectal cancer

Introduction

Colorectal cancer (CRC) ranks as the third most prevalent malignancy globally, with a concerning rise in incidence among young adults. Despite progress in understanding genetic predispositions and lifestyle risk factors, the intricate molecular mechanisms of CRC demand exploration. MicroRNAs (miRNAs) emerge as key regulators of gene expression and their deregulation in tumor cells play pivotal roles in cancer progression.

Methods

NanoString's nCounter technology was utilized to measure the expression of 827 cancer-related miRNAs in tumor tissue and adjacent non-involved normal colon tissue from five patients with locoregional CRC progression. These expression profiles were then compared to those from the primary colon adenocarcinoma (COAD) cohort in The Cancer Genome Atlas (TCGA).

Results and discussion

Intriguingly, 156 miRNAs showed a contrasting dysregulation pattern in reccurent tumor compared to their expression in the TCGA COAD cohort. This observation implies dynamic alterations in miRNA expression patterns throughout disease progression. Our exploratory study contributes to understanding the regulatory landscape of recurrent CRC, emphasizing the role of miRNAs in disease relapse. Notable findings include the prominence of let-7 miRNA family, dysregulation of key target genes, and dynamic changes in miRNA expression patterns during progression. Univariate Cox proportional hazard models highlighted miRNAs associated with adverse outcomes and potential protective factors. The study underscores the need for more extensive investigations into miRNA dynamics during tumor progression and the value of stage specific biomarkers for prognosis.

Cancer-associated fibroblasts-secreted exosomal miR-92a-3p promotes tumor growth and stemness in hepatocellular carcinoma through activation of Wnt/β-catenin signaling pathway by suppressing AXIN1

Cancer-associated fibroblasts (CAFs) are a major cellular component in the tumor microenvironment and have been shown to exhibit protumorigenic effects in hepatocellular carcinoma (HCC). This study aimed to delve into the mechanisms underlying the tumor-promoting effects of CAFs in HCC. Small RNA sequencing was conducted to screen differential expressed microRNAs in exosomes derived from CAFs and normal fibroblasts (NFs). The miR-92a-3p expression was then measured using reverse transcriptase quantitative real-time PCR in CAFs, NFs, CAFs-derived exosomes (CAFs-Exo), and NF-derived exosomes (NFs-Exo). Compared to NFs or NF-Exo, CAFs and CAFs-Exo significantly promoted HCC cell proliferation, migration, and stemness. Additionally, compared to NFs or NF-Exo, miR-92a-3p level was notably higher in CAFs and CAFs-Exo, respectively. Exosomal miR-92a-3p was found to enhance HCC cell proliferation, migration, and stemness. Meanwhile, AXIN1 was targeted by miR-92a-3p. Exosomal miR-92a-3p could activate β-catenin/CD44 signaling in HCC cells by inhibiting AXIN1 messenger RNA. Furthermore, in vivo studies verified that exosomal miR-92a-3p notably promoted tumor growth and stemness through targeting AXIN1/β-catenin axis. Collectively, CAFs secreted exosomal miR-92a-3p was capable of promoting growth and stemness in HCC through activation of Wnt/β-catenin signaling pathway by suppressing AXIN1. Therefore, targeting CAFs-derived miR-92a-3p may be a potential strategy for treating HCC.

Crosstalk between CXCL12/CXCR4/ACKR3 and the STAT3 Pathway

The reciprocal modulation between the CXCL12/CXCR4/ACKR3 axis and the STAT3 signaling pathway plays a crucial role in the progression of various diseases and neoplasms. Activation of the CXCL12/CXCR4/ACKR3 axis triggers the STAT3 pathway through multiple mechanisms, while the STAT3 pathway also regulates the expression of CXCL12. This review offers a thorough and systematic analysis of the reciprocal regulatory mechanisms between the CXCL12/CXCR4/ACKR3 signaling axis and the STAT3 signaling pathway in the context of diseases, particularly tumors. It explores the potential clinical applications in tumor treatment, highlighting possible therapeutic targets and novel strategies for targeted tumor therapy.

miRNA patterns in male LUSC patients - the 3-way mirror: Tissue, plasma and exosomes

Lung cancer remains one of the leading causes of cancer-related deaths worldwide. It is classified into two main histological groups: non-small cell lung cancer (NSCLC) and small cell lung cancer. Improving the outcome of cancer patients could be possible by enhancing the early diagnosis. In the current study, we evaluated the levels of three microRNAs - miR-21-5p, miR-155-5p, and miR-181a-5p in tumor (TT) vs adjacent normal tissue (NT), as well as their expression levels in plasma and extracellular vesicles (EVs) from plasma in lung squamous cell carcinoma (LUSC) male patients vs healthy individuals as means to identify a panel of miRNAs that could serve as novel biomarkers for the diagnosis of LUSC in male patients. Matched paired tissue samples from male LUSC (n=40) patients were used for miRNA expression analysis. MiR-21-5p and miR-155-5p in tumor tissue were overexpressed, while underexpression of miR-181a-5p was observed in LUSC TT vs NT. These results were further validated in the TCGA LUSC dataset, considering 279 male samples. These alterations of miR-21-5p, miR-181a-5p, and miR-155-5p in tumor tissue are also present in plasma and plasma extracellular vesicles in LUSC male patients. In addition, ROC curves were performed to assess the sensitivity and specificity of different combinations of these miRNAs, confirming a high diagnostic accuracy for LUSC of up to 88 % in male subjects. The expression levels in tissue samples and the abundance in plasma and plasma EVs of the three miRNAs combined - miR-21-5p, miR-155-5p and miR-181a-5p - could be considered for further studies on biomarkers for the early detection of LUSC in male subjects.

The multifaceted role of extracellular vesicles (EVs) in colorectal cancer: metastasis, immune suppression, therapy resistance, and autophagy crosstalk

Extracellular vesicles (EVs) are lipid bilayer structures released by all cells and widely distributed in all biological fluids. EVs are implicated in diverse physiopathological processes by orchestrating cell-cell communication. Colorectal cancer (CRC) is one of the most common cancers worldwide, with metastasis being the leading cause of mortality in CRC patients. EVs contribute significantly to the advancement and spread of CRC by transferring their cargo, which includes lipids, proteins, RNAs, and DNAs, to neighboring or distant cells. Besides, they can serve as non-invasive diagnostic and prognostic biomarkers for early detection of CRC or be harnessed as effective carriers for delivering therapeutic agents. Autophagy is an essential cellular process that serves to remove damaged proteins and organelles by lysosomal degradation to maintain cellular homeostasis. Autophagy and EV release are coordinately activated in tumor cells and share common factors and regulatory mechanisms. Although the significance of autophagy and EVs in cancer is well established, the exact mechanism of their interplay in tumor development is obscure. This review focuses on examining the specific functions of EVs in various aspects of CRC, including progression, metastasis, immune regulation, and therapy resistance. Further, we overview emerging discoveries relevant to autophagy and EVs crosstalk in CRC.

SAP deletion promotes malignant insulinoma progression by inducing CXCL12 secretion from CAFs via the CXCR4/p38/ERK signalling pathway

Malignant insulinoma is an extremely rare type of functioning pancreatic neuroendocrine tumour with a high degree of malignancy and a high incidence of metastasis. However, it is still unclear how malignant insulinomas develop and metastasize. Serum amyloid P component (SAP), a member of the pentraxin protein family, is an acute-phase protein secreted by liver cells. The role of SAP in insulinoma and the related mechanism are still unknown. To determine the effect of SAP on insulinoma, we crossed Rip1-Tag2 mice, which spontaneously develop insulinoma, and SAP knockout (KO) mice to generate Rip1-Tag2;SAP-/- mice. We found that SAP deletion significantly promoted the growth, invasion and metastasis of malignant insulinoma through C-X-C motif chemokine ligand 12 (CXCL12) secreted by cancer-associated fibroblasts (CAFs). Further study showed that SAP deletion promoted CXCL12 secretion by CAFs through the CXCR4/p38/ERK signalling pathway. These findings reveal a novel role and mechanism of SAP in malignant insulinoma and provide direct evidence that SAP may be a therapeutic agent for this disease.

Baicalin reduces inflammation to inhibit lung cancer via targeting SOCS1/NF-κB/STAT3 axis

Inflammation affects several aspects of lung cancer progression including cell proliferation, metastasis, apoptosis, angiogenesis, and drug resistance. Baicalin, an active component of Scutellaria baicalensis Georgi, exhibits anticancer activity in various cancers. However, the effects of baicalin on lung cancer and the underlying molecular mechanisms remain largely unknown. This study is to explore the effect and mechanism of baicalin on lung cancer cell A549 and urethane-induced mouse lung cancer. A cell viability assay, colony formation assay, wound healing assay, acridine orange/ethidium bromide (AO/EB) staining assay, Western blot assay, urethane-induced mouse lung cancer model, hematoxylin and eosin (HE) staining, immunohistochemistry (IHC), and ELISA assay were performed to investigate the effects of baicalin on lung cancer in vitro and in vivo. Network pharmacology analysis, molecular docking, gene silencing assays, and LPS-induced inflammation model were utilized to explore the molecular mechanisms underlying the effect of baicalin on lung cancer. Baicalin showed significant anti-proliferative, anti-migratory, anti-inflammatory and pro-apoptotic effects in vitro; it also inhibited the progression of urethane-induced mouse lung cancer in vivo. Mechanistically, suppressor of cytokine signaling 1 (SOCS1) was the key determinant for baicalin-induced inhibition of lung cancer. Baicalin increased SOCS1 expression to inactivate the NF-κB/STAT3 pathway to inhibit lung cancer in vitro and in vivo. Taken together, baicalin reduces inflammation to inhibit lung cancer via targeting SOCS1/NF-κB/STAT3 axis, providing a prospective compound and novel target for lung cancer treatment.

Function and mechanism of exosomes derived from different cells as communication mediators in colorectal cancer metastasis

Colorectal cancer (CRC) ranks as the second leading cause of cancer-related mortality, with metastasis being the primary determinant of poor prognosis in patients. Investigating the molecular mechanisms underlying CRC metastasis is currently a prominent and challenging area of research. Exosomes, as crucial intercellular communication mediators, facilitate the transfer of metabolic and genetic information from cells of origin to recipient cells. Their roles in mediating information exchange between CRC cells and immune cells, fibroblasts, and other cell types are pivotal in reshaping the tumor microenvironment, regulating key biological processes such as invasion, migration, and formation of pre-metastatic niche. This article comprehensively examines the communication function and mechanism of exosomes derived from different cells in cancer metastasis, while also presenting an outlook on current research advancements and future application prospects. The aim is to offer a distinctive perspective that contributes to accurate diagnosis and rational treatment strategies for CRC.

The rising roles of exosomes in the tumor microenvironment reprogramming and cancer immunotherapy

Exosomes are indispensable for intercellular communications. Tumor microenvironment (TME) is the living environment of tumor cells, which is composed of various components, including immune cells. Based on TME, immunotherapy has been recently developed for eradicating cancer cells by reactivating antitumor effect of immune cells. The communications between tumor cells and TME are crucial for tumor development, metastasis, and drug resistance. Exosomes play an important role in mediating these communications and regulating the reprogramming of TME, which affects the sensitivity of immunotherapy. Therefore, it is imperative to investigate the role of exosomes in TME reprogramming and the impact of exosomes on immunotherapy. Here, we review the communication role of exosomes in regulating TME remodeling and the efficacy of immunotherapy, as well as summarize the underlying mechanisms. Furthermore, we also introduce the potential application of the artificially modified exosomes as the delivery systems of antitumor drugs. Further efforts in this field will provide new insights on the roles of exosomes in intercellular communications of TME and cancer progression, thus helping us to uncover effective strategies for cancer treatment.

Cancer-derived exosomes as novel biomarkers in metastatic gastrointestinal cancer

Gastrointestinal cancer (GIC) is the most prevalent and highly metastatic malignant tumor and has a significant impact on mortality rates. Nevertheless, the swift advancement of contemporary technology has not seamlessly aligned with the evolution of detection methodologies, resulting in a deficit of innovative and efficient clinical assays for GIC. Given that exosomes are preferentially released by a myriad of cellular entities, predominantly originating from neoplastic cells, this confers exosomes with a composition enriched in cancer-specific constituents. Furthermore, exosomes exhibit ubiquitous presence across diverse biological fluids, endowing them with the inherent advantages of non-invasiveness, real-time monitoring, and tumor specificity. The unparalleled advantages inherent in exosomes render them as an ideal liquid biopsy biomarker for early diagnosis, prognosticating the potential development of GIC metastasis.In this review, we summarized the latest research progress and possible potential targets on cancer-derived exosomes (CDEs) in GIC with an emphasis on the mechanisms of exosome promoting cancer metastasis, highlighting the potential roles of CDEs as the biomarker and treatment in metastatic GIC.

Unveiling the oncogenic role of CLDN11-secreting fibroblasts in gastric cancer peritoneal metastasis through single-cell sequencing and experimental approaches

BACKGROUND

Fibroblasts are necessary to the progression of cancer. However, the role of fibroblasts in peritoneal metastasis (PM) of gastric cancer (GC) remains elusive. In this study, we would explore the role of fibroblasts mediated cell interaction in PM of GC.

METHODS

Single-cell sequencing data from public database GSE183904 was used to explore the specific fibroblast cluster. Fibroblasts were extracted from PM and GC tissues. The expression level of CXCR7 was verified by western blot, immunohistochemistry. The role of CLDN11 was investigate through in vitro and in vivo study. Multiple immunohistochemistry was used to characterize the tumor microenvironment.

RESULTS

CXCR7-positive fibroblasts were significantly enriched in PM of GC. CXCR7 could promote the expression of CLDN11 through activation of the AKT pathway in fibroblasts. Fibroblasts promote the GC proliferation and peritoneal metastasis by secreting CLDN11 in vitro and in vivo. Furthermore, it was revealed that CXCR7-positive fibroblasts were significantly associated with M2-type macrophages infiltration in tissues.

CONCLUSION

CXCR7-positive fibroblasts play an essential role in PM of GC via CLDN11. Therapy targeting CXCR7-positive fibroblasts or CLDN11 may be helpful in the treatment of GC with PM.

Intercellular crosstalk between cancer cells and cancer-associated fibroblasts via exosomes in gastrointestinal tumors

Gastrointestinal (GI) tumors are a significant global health threat, with high rates of morbidity and mortality. Exosomes contain various biologically active molecules like nucleic acids, proteins, and lipids and can serve as messengers for intercellular communication. They play critical roles in the exchange of information between tumor cells and the tumor microenvironment (TME). The TME consists of mesenchymal cells and components of the extracellular matrix (ECM), with fibroblasts being the most abundant cell type in the tumor mesenchyme. Cancer-associated fibroblasts (CAFs) are derived from normal fibroblasts and mesenchymal stem cells that are activated in the TME. CAFs can secrete exosomes to modulate cell proliferation, invasion, migration, drug resistance, and other biological processes in tumors. Additionally, tumor cells can manipulate the function and behavior of fibroblasts through direct cell-cell interactions. This review provides a summary of the intercellular crosstalk between GI tumor cells and CAFs through exosomes, along with potential underlying mechanisms.

METTL14 enhances the m6A modification level of lncRNA MSTRG.292666.16 to promote the progression of non-small cell lung cancer

BACKGROUND

m6A modification has close connection with the occurrence, development, and prognosis of tumors. This study aimed to explore the roles of m6A modification and its related mechanisms in non-small cell lung cancer (NSCLC).

METHODS

NSCLC tissues and their corresponding para-cancerous tissues were collected to determine the m6A levels of total RNA/lncRNAs and the expression of m6A modification-related genes/lncRNAs. Then, A549 cells were transfected with si-METTL14 or oe-METTL14, and the cell transfection efficiency was assessed. Subsequently, the viability, apoptosis, cell colony formation, migration and invasion of the different cells were determined. Finally, the nude mouse tumorigenicity experiments were performed to observe the effects of METTL14 in vivo.

RESULTS

Compared to the para-NSCLC tissues, the m6A level and METTL14 expression were both significantly increased in the NSCLC tissues (P < 0.05). Based on the expression of METTL14 in the different cell lines, A549 cells were chosen for further experiments. Then, the A549 cells with METTL14 knockdown and overexpression were successfully established, as well as it was found that METTL14 knockdown could inhibit the viability, colony formation, migration, and invasion of A549 cells, while facilitate their apoptosis. In vivo experiments also showed that METTL14 knockdown could inhibit tumor formation and growth. Additionally, the m6A level of MSTRG.292666.16 was higher in the NSCLC tissues; and after METTL14 knockdown, the expression and m6A level of MSTRG.292666.16 were both significantly reduced in A549 cells, and vice versa.

CONCLUSION

METTL14 may promote the progression of NSCLC through up-regulating MSTRG.292666.16 and enhance its m6A modification level.

Perineural invasion in colorectal cancer: mechanisms of action and clinical relevance

BACKGROUND

In recent years, the significance of the nervous system in the tumor microenvironment has gained increasing attention. The bidirectional communication between nerves and cancer cells plays a critical role in tumor initiation and progression. Perineural invasion (PNI) occurs when tumor cells invade the nerve sheath and/or encircle more than 33% of the nerve circumference. PNI is a common feature in various malignancies and is associated with tumor invasion, metastasis, cancer-related pain, and unfavorable clinical outcomes. The colon and rectum are highly innervated organs, and accumulating studies support PNI as a histopathologic feature of colorectal cancer (CRC). Therefore, it is essential to investigate the role of nerves in CRC and comprehend the mechanisms of PNI to impede tumor progression and improve patient survival.

CONCLUSION

This review elucidates the clinical significance of PNI, summarizes the underlying cellular and molecular mechanisms, introduces various experimental models suitable for studying PNI, and discusses the therapeutic potential of targeting this phenomenon. By delving into the intricate interactions between nerves and tumor cells, we hope this review can provide valuable insights for the future development of CRC treatments.

Extracellular vesicles associated microRNAs: Their biology and clinical significance as biomarkers in gastrointestinal cancers

Gastrointestinal (GI) cancers, including colorectal, gastric, esophageal, pancreatic, and liver, are associated with high mortality and morbidity rates worldwide. One of the underlying reasons for the poor survival outcomes in patients with these malignancies is late disease detection, typically when the tumor has already advanced and potentially spread to distant organs. Increasing evidence indicates that earlier detection of these cancers is associated with improved survival outcomes and, in some cases, allows curative treatments. Consequently, there is a growing interest in the development of molecular biomarkers that offer promise for screening, diagnosis, treatment selection, response assessment, and predicting the prognosis of these cancers. Extracellular vesicles (EVs) are membranous vesicles released from cells containing a repertoire of biological molecules, including nucleic acids, proteins, lipids, and carbohydrates. MicroRNAs (miRNAs) are the most extensively studied non-coding RNAs, and the deregulation of miRNA levels is a feature of cancer cells. EVs miRNAs can serve as messengers for facilitating interactions between tumor cells and the cellular milieu, including immune cells, endothelial cells, and other tumor cells. Furthermore, recent years have witnessed considerable technological advances that have permitted in-depth sequence profiling of these small non-coding RNAs within EVs for their development as promising cancer biomarkers -particularly non-invasive, liquid biopsy markers in various cancers, including GI cancers. Herein, we summarize and discuss the roles of EV-associated miRNAs as they play a seminal role in GI cancer progression, as well as their promising translational and clinical potential as cancer biomarkers as we usher into the area of precision oncology.

Predictive values of circulating miR-146a and miR-155 for disease activity and clinical response to TNF-α blocking therapy in patients with ankylosing spondylitis

OBJECTIVE

Ankylosing spondylitis is an insidiously progressive and debilitating form of arthritis involving the axial skeleton. MicroRNAs have been reported to act as candidate biomarkers for ankylosing spondylitis diagnosis and progression. The study aimed to assess the roles of circulating miR-146a and miR-155 in ankylosing spondylitis and their prediction to clinical response to TNF-α blocking therapy.

METHODS

The study included 62 ankylosing spondylitis patients who were given originator TNFi with a 6-month period. Responders to anti-TNF treatment were defined as those reaching the Assessment of SpondyloArthritis international Society 40 (ASAS40) response at the 6-month interval, and nonresponders were defined those not (n = 24).

RESULTS

The ankylosing spondylitis patients at M0 (before beginning TNFi treatment) had higher serum levels of miR-146a and miR-155 than the healthy controls (p < .0001). Lower serum levels of miR-146a and miR-155 were noted in the responders (n = 38) compared with the nonresponders (n = 24) at different time points after anti-TNF treatment (p < .0001). The serum levels of miR-146a and miR-155 alone or in combination used to predict treatment outcomes produced AUCs of 0.884, 0.902, and 0.936, respectively. We submitted the following variables: miR-146a and miR-155 levels, BASDAI, ASDASCRP, ESR (mm/h), and CRP (mg/L) into multivariate logistic regression analysis, and results showed that higher levels of miR-146a (OR: 13.75, 95%CI: 1.32 to 143.57, p = .029), miR-155 (OR: 5.74, 95% CI: 1.63 to 20.20, p = .006), and ESR (OR: 1.08, 95% CI: 1.01 to 1.15, p = .022) were independent baseline predictors of ASAS40 response at 6-month anti-TNF-a treatment.

CONCLUSION

These findings obtained from the study suggest that high serum levels of miR-146a and miR-155 could aid in prediction of poor treatment outcomes after TNF-α blocking therapy.

From inflammation to metastasis: The central role of miR-155 in modulating NF-κB in cancer

Cancer is a multifaceted, complex disease characterized by unchecked cell growth, genetic mutations, and dysregulated signalling pathways. These factors eventually cause evasion of apoptosis, sustained angiogenesis, tissue invasion, and metastasis, which makes it difficult for targeted therapeutic interventions to be effective. MicroRNAs (miRNAs) are essential gene expression regulators linked to several biological processes, including cancer and inflammation. The NF-κB signalling pathway, a critical regulator of inflammatory reactions and oncogenesis, has identified miR-155 as a significant participant in its modulation. An intricate network of transcription factors known as the NF-κB pathway regulates the expression of genes related to inflammation, cell survival, and immunological responses. The NF-κB pathway's dysregulation contributes to many cancer types' development, progression, and therapeutic resistance. In numerous cancer models, the well-studied miRNA miR-155 has been identified as a crucial regulator of NF-κB signalling. The p65 subunit and regulatory molecules like IκB are among the primary targets that miR-155 directly targets to alter NF-κB activity. The molecular processes by which miR-155 affects the NF-κB pathway are discussed in this paper. It also emphasizes the miR-155's direct and indirect interactions with important NF-κB cascade elements to control the expression of NF-κB subunits. We also investigate how miR-155 affects NF-κB downstream effectors in cancer, including inflammatory cytokines and anti-apoptotic proteins.

The emerging role of medical foods and therapeutic potential of medical food-derived exosomes

Medical food is consumed for the purpose of improving specific nutritional requirements or disease conditions, such as inflammation, diabetes, and cancer. It involves partial or exclusive feeding for fulfilling unique nutritional requirements of patients and is different from medicine, consisting of basic nutrients, such as polyphenols, vitamins, sugars, proteins, lipids, and other functional ingredients to nourish the patients. Recently, studies on extracellular vesicles (exosomes) with therapeutic and drug carrier potential have been actively conducted. In addition, there have been attempts to utilize exosomes as medical food components. Consequently, the application of exosomes is expanding in different fields with increasing research being conducted on their stability and safety. Herein, we introduced the current trends of medical food and the potential utilization of exosomes in them. Moreover, we proposed Medi-Exo, a exosome-based medical food. Furthermore, we comprehensively elucidate various disease aspects between medical food-derived exosomes (Medi-Exo) and therapeutic natural bionanocomposites. This review highlights the therapeutic challenges regarding Medi-Exo and its potential health benefits.

Expression of long noncoding RNA MEG3 and microRNA-302b-3p in colon cancer: Correlation with clinical stage and value in predicing prognosis after surgical treatment

BACKGROUND

More and more long non-coding RNAs and microRNAs have been found to have significant changes in expression levels during the occurrence and development of tumors, which can affect the expression of tumor suppressor genes or oncogenes and play an important role in the proliferation and metastasis of cancer cells.

AIM

To investigate the correlation between the expression of long non-coding RNA maternal imprinted gene 3 (LncRNA MEG3) and microRNA (miR)-302b-3p in colon cancer and clinical stage and analyze their value in predicting the prognosis after surgical treatment.

METHODS

A total of 97 patients with colon cancer treated at Jinhua Hospital of TCM from January 2017 to March 2022 were selected to compare the expression of LncRNA MEG3 and miR-302b-3p in different tissues, analyze the correlation between the expression of LncRNA MEG3 and miR-302b-3p and clinical pathological characteristics, compare the recurrence in patients with different LncRNA MEG3 and miR-302b-3p expression, analyze the factors affecting the recurrence of colon cancer after surgery, and analyze the impact of the interaction between LncRNA MEG3 and miR-302b-3p on the recurrence of colon cancer. The predictive value of LncRNA MEG3 and miR-302b-3p expression for the recurrence of colon cancer after surgery was evaluated.

RESULTS

The expression of LncRNA MEG3 and miR-302b-3p in colon cancer tissues was lower than that in tumor-adjacent tissues (P < 0.05). The expression of LncRNA MEG3 and miR-302b-3p in colon cancer tissues was not correlated with sex, age, or tumor size (P > 0.05), but was correlated with tumor differentiation, clinical stage, and lymph node metastasis (P < 0.05). In colon cancer tissues, the recurrence rate in patients with high LncRNA MEG3 and miR-302b-3p expression was lower than that of patients with lower LncRNA MEG3 and miR-302b-3p expression (P < 0.05). Tumor differentiation degree, clinical stage, and lymph node metastasis were all identified to be risk factors for colon cancer recurrence, and LncRNA MEG3 and miR-302b-3p expression were protective factors for colon cancer recurrence (P < 0.05). The interaction analysis showed that the synergistic effect of simultaneous exposure to LncRNA MEG3 and miR-302b-3p was 15.888 times greater than the effect of exposure to either LncRNA MEG3 or miR-302b-3p alone, and when simultaneously exposing to both, 56.98% of the risk of colon cancer recurrence was attributed to their synergistic effect. The area under the curve (AUC) (95% confidence interval [CI]) of LncRNA MEG3 and miR-302b-3p in predicting the prognosis of colon cancer patients was 0.720 (0.620-0.807) and 0.767 (0.670-0.847), respectively, and that of the combined prediction was 0.892 (0.813-0.946), with a sensitivity and specificity of 92.31% and 83.33%, respectively, which were significantly higher than those of either LncRNA MEG3 or miR-302b-3p alone.

CONCLUSION

The down-regulated expression of LncRNA MEG3 and miR-302b-3p in colon cancer is related to clinical stage. Clinical detection of their expression can be used to determine the malignant degree of tumor and predict the prognosis of surgical treatment, thus providing reference for adjustment of clinical treatment plan.

Epigenetic and metabolic reprogramming in inflammatory bowel diseases: diagnostic and prognostic biomarkers in colorectal cancer

BACKGROUND AND AIM

"Inflammatory bowel disease" (IBD) is a chronic, relapsing inflammatory disease of the intestinal tract that typically begins at a young age and might transit to colorectal cancer (CRC). In this manuscript, we discussed the epigenetic and metabolic change to present a extensive view of IBDs transition to CRC. This study discusses the possible biomarkers for evaluating the condition of IBDs patients, especially before the transition to CRC.

RESEARCH APPROACH

We searched "PubMed" and "Google Scholar" using the keywords from 2000 to 2022.

DISCUSSION

In this manuscript, interesting titles associated with IBD and CRC are discussed to present a broad view regarding the epigenetic and metabolic reprogramming and the biomarkers.

CONCLUSION

Epigenetics can be the main reason in IBD transition to CRC, and Hypermethylation of several genes, such as VIM, OSM4, SEPT9, GATA4 and GATA5, NDRG4, BMP3, ITGA4 and plus hypomethylation of LINE1 can be used in IBD and CRC management. Epigenetic, metabolisms and microbiome-derived biomarkers, such as Linoleic acid and 12 hydroxy 8,10-octadecadienoic acid, Serum M2-pyruvate kinase and Six metabolic genes (NAT2, XDH, GPX3, AKR1C4, SPHK and ADCY5) expression are valuable biomarkers for early detection and transition to CRC condition. Some miRs, such as miR-31, miR-139-5p, miR -155, miR-17, miR-223, miR-370-3p, miR-31, miR -106a, miR -135b and miR-320 can be used as biomarkers to estimate IBD transition to CRC condition.

MYL9 expressed in cancer-associated fibroblasts regulate the immune microenvironment of colorectal cancer and promotes tumor progression in an autocrine manner

BACKGROUND

The tumor microenvironment (TME) is an important factor that regulates the progression of colorectal cancer (CRC). Cancer-associated fibroblasts (CAFs) are the main mesenchymal cells in the TME and play a vital role in tumor progression; however, the specific underlying mechanisms require further study.

METHODS

Multiple single-cell and transcriptome data were analyzed and validated. Primary CAFs isolation, CCK8 assay, co-culture assay, western blotting, multiple immunofluorescence, qRT-PCR, ELISA, immunoprecipitation, ChIP, double luciferase, and animal experiments were used to explore the potential mechanism of MYL9 regulation in CRC.

RESULTS

Our findings revealed that MYL9 was predominantly localized and expressed in CAFs rather than in CRC cells, and bioinformatics analysis revealed that high MYL9 expression was strongly associated with poor overall and disease-free survival in various tumors. In addition, high MYL9 expression is closely associated with M2 macrophage infiltration, which can lead to an immunosuppressive microenvironment in CRC, making it insensitive to immunotherapy. Mechanically, MYL9 can regulate the secretion of CAFs on CCL2 and TGF-β1, thus affecting the immune microenvironment and progression of CRC. In addition, MYL9 bounded with IQGAP1 to regulate CCL2 and TGF-β1 secretion through the ERK 1/2 pathway, and CCL2 and TGF-β1 synergistically promoted CRC cells progression through the PI3K-AKT pathway. Furthermore, MYL9 promotes epithelial-mesenchymal transition (EMT) in CRC. During the upstream regulation of MYL9 in CAFs, we found that the EMT transcription factor ZEB1 could bind to the MYL9 promoter in CAFs, enhancing the activity and function of MYL9. Therefore, MYL9 is predominantly expressed in CAFs and can indirectly influence tumor biology and EMT by affecting CAFs protein expression in CRC.

CONCLUSIONS

MYL9 regulates the secretion of cytokines and chemokines in CAFs, which can affect the immune microenvironment of CRC and promote CRC progression. The relationship between MYL9 expression and CRC clinical staging and immunotherapy is closer in CAFs than in tumor cells; therefore, studies using CAFs as a model deserve more attention when exploring tumor molecular targets in clinical research.

Exosome-derived miR-372-5p promotes stemness and metastatic ability of CRC cells by inducing macrophage polarization

Colorectal cancer (CRC) is the most common malignancy in the digestive system, and tumor metastasis is the main cause of death in clinical patients with CRC. It has been shown that exosomes promote phenotypic changes in macrophages and tumor metastasis in the CRC tumor microenvironment. In this study, we used miRNA-seq technology to screen out the highly expressed miR-372-5p among the miRNAs differentially expressed in plasma exosomes of clinical CRC patients. It was found that miR-372-5p highly expressed in HCT116 exosomes could be phagocytosed by macrophages and promote their polarization into M2 macrophages by regulating the PTEN/AKT pathway. Meanwhile, co-culture of CRC cells with conditioned medium (CM) of macrophages enhanced the EMT, stemness and metastasis of CRC cells. Mechanistically, CRC cells exosome-derived miR-372-5p induced polarized M2 macrophages to secrete chemokine C-X-C-Motif Ligand 12 (CXCL12), which activated the WNT/β-catenin pathway to promote the EMT, stemness and metastatic ability of CRC cells. In summary, this study elucidated the molecular mechanism of exosomal miR-372-5p promoting metastasis and stemness in CRC, which may provide new therapeutic targets for CRC metastasis and prognosis assessment.

The Role of the Transforming Growth Factor-β Signaling Pathway in Gastrointestinal Cancers

Transforming growth factor-β (TGF-β) has attracted attention as a tumor suppressor because of its potent growth-suppressive effect on epithelial cells. Dysregulation of the TGF-β signaling pathway is considered to be one of the key factors in carcinogenesis, and genetic alterations affecting TGF-β signaling are extraordinarily common in cancers of the gastrointestinal system, such as hereditary nonpolyposis colon cancer and pancreatic cancer. Accumulating evidence suggests that TGF-β is produced from various types of cells in the tumor microenvironment and mediates extracellular matrix deposition, tumor angiogenesis, the formation of CAFs, and suppression of the anti-tumor immune reaction. It is also being considered as a factor that promotes the malignant transformation of cancer, particularly the invasion and metastasis of cancer cells, including epithelial-mesenchymal transition. Therefore, elucidating the role of TGF-β signaling in carcinogenesis, cancer invasion, and metastasis will provide novel basic insight for diagnosis and prognosis and the development of new molecularly targeted therapies for gastrointestinal cancers. In this review, we outline an overview of the complex mechanisms and functions of TGF-β signaling. Furthermore, we discuss the therapeutic potentials of targeting the TGF-β signaling pathway for gastrointestinal cancer treatment and discuss the remaining challenges and future perspectives on targeting this pathway.

Exosomal microRNA/miRNA Dysregulation in Respiratory Diseases: From Mycoplasma-Induced Respiratory Disease to COVID-19 and Beyond

Respiratory diseases represent a significant economic and health burden worldwide, affecting millions of individuals each year in both human and animal populations. MicroRNAs (miRNAs) play crucial roles in gene expression regulation and are involved in various physiological and pathological processes. Exosomal miRNAs and cellular miRNAs have been identified as key regulators of several immune respiratory diseases, such as chronic respiratory diseases (CRD) caused by Mycoplasma gallisepticum (MG), Mycoplasma pneumoniae pneumonia (MMP) caused by the bacterium Mycoplasma pneumoniae, coronavirus disease 2019 (COVID-19), chronic obstructive pulmonary disease (COPD), asthma, and acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Consequently, miRNAs seem to have the potential to serve as diagnostic biomarkers and therapeutic targets in respiratory diseases. In this review, we summarize the current understanding of the functional roles of miRNAs in the above several respiratory diseases and discuss the potential use of miRNAs as stable diagnostic biomarkers and therapeutic targets for several immune respiratory diseases, focusing on the identification of differentially expressed miRNAs and their targeting of various signaling pathways implicated in disease pathogenesis. Despite the progress made, unanswered questions and future research directions are discussed to facilitate personalized and targeted therapies for patients with these debilitating conditions.

Define cancer-associated fibroblasts (CAFs) in the tumor microenvironment: new opportunities in cancer immunotherapy and advances in clinical trials

Despite centuries since the discovery and study of cancer, cancer is still a lethal and intractable health issue worldwide. Cancer-associated fibroblasts (CAFs) have gained much attention as a pivotal component of the tumor microenvironment. The versatility and sophisticated mechanisms of CAFs in facilitating cancer progression have been elucidated extensively, including promoting cancer angiogenesis and metastasis, inducing drug resistance, reshaping the extracellular matrix, and developing an immunosuppressive microenvironment. Owing to their robust tumor-promoting function, CAFs are considered a promising target for oncotherapy. However, CAFs are a highly heterogeneous group of cells. Some subpopulations exert an inhibitory role in tumor growth, which implies that CAF-targeting approaches must be more precise and individualized. This review comprehensively summarize the origin, phenotypical, and functional heterogeneity of CAFs. More importantly, we underscore advances in strategies and clinical trials to target CAF in various cancers, and we also summarize progressions of CAF in cancer immunotherapy.

Extracellular vesicles: Emerging mediators of cell communication in gastrointestinal cancers exhibiting metabolic abnormalities

There is a complex interaction between pro-tumoural and anti-tumoural networks in the tumour microenvironment (TME). Throughout tumourigenesis, communication between malignant cells and various cells of the TME contributes to metabolic reprogramming. Tumour Dysregulation of metabolic pathways offer an evolutional advantage in the TME and enhance the tumour progression, invasiveness, and metastasis. Therefore, understanding these interactions within the TME is crucial for the development of innovative cancer treatments. Extracellular vesicles (EVs) serve as carriers of various materials that include microRNAs, proteins, and lipids that play a vital role in the communication between tumour cells and non-tumour cells. EVs are actively involved in the metabolic reprogramming process. This review summarized recent findings regarding the involvement of EVs in the metabolic reprogramming of various cells in the TME of gastrointestinal cancers. Additionally, we highlight identified microRNAs involved in the reprogramming process in this group of cancers and explained the abnormal tumour metabolism targeted by exosomal cargos as well as the novel potential therapeutic approaches.

Emerging functions and clinical applications of exosomal microRNAs in diseases

Exosomes are an important group of extracellular vesicles that transfer several kinds of biomolecules and facilitate cell-cell communication. The content of exosomes, particularly the amounts of microRNA (miRNAs) inside these vesicles, demonstrates a disease-specific pattern reflecting pathogenic processes and may be employed as a diagnostic and prognostic marker. miRNAs may enter recipient cells through exosomes and generate a RISC complex that can cause degradation of the target mRNAs or block translation of their corresponding proteins. Therefore, exosome-derived miRNAs constitute an important mechanism of gene regulation in recipient cells. The miRNA content of exosomes can be used as an important tool in the detection of diverse disorders, particularly cancers. This research field has an important situation in cancer diagnosis. In addition, exosomal microRNAs offer a great deal of promise in the treatment of human disorders. However, there are still certain challenges to be resolved. The most important challenges are as follow: the detection of exosomal miRNAs should be standardized, exosomal miRNAs-associated studies should be conducted in large number of clinical samples, and experiment settings and detection criteria should be consistent across different labs. The goal of this article is to present an overview of the effects of exosome-derived microRNAs on a variety of diseases, including gastrointestinal, pulmonary, neurological, and cardiovascular diseases, with a particular emphasis on malignancies.

Regulatory role of exosomes in colorectal cancer progression and potential as biomarkers

Colorectal cancer (CRC) remains an enormous challenge to human health worldwide. Unfortunately, the mechanism underlying CRC progression is not well understood. Mounting evidence has confirmed that exosomes play a vital role in CRC progression, which has attracted extensive attention among researchers. In addition to acting as messengers between CRC cells, exosomes also participate in the CRC immunomodulatory process and reshape immune function. As stable message carriers and liquid biopsy option under development, exosomes are promising biomarkers in the diagnosis or treatment of CRC. In this review we have described and analyzed the biogenesis and release of exosomes and current research on the role of exosomes in immune regulation and metastasis of CRC. Moreover, we have discussed candidate exosomal molecules as potential biomarkers to diagnose CRC, predict CRC progression, or determine CRC chemoresistance, and described the significance of exosomes in the immunotherapy of CRC. This review provides insight to further understand the role of exosomes in CRC progression and identify valuable biomarkers that facilitate the clinical management of CRC patients.

Extracellular vesicle-circEHD2 promotes the progression of renal cell carcinoma by activating cancer-associated fibroblasts

BACKGROUND

The encapsulation of circular RNAs (circRNAs) into extracellular vesicles (EVs) enables their involvement in intercellular communication and exerts an influence on the malignant advancement of various tumors. However, the regulatory role of EVs-circRNA in renal cell carcinoma (RCC) remains elusive.

METHODS

The in vitro and in vivo functional experiments were implemented to measure the effects of circEHD2 on the phenotype of RCC. The functional role of EVs-circEHD2 on the activation of fibroblasts was assessed by collagen contraction assay, western blotting, and enzyme-linked immunosorbent assay (ELISA). The mechanism was investigated by RNA pull-down assay, RNA immunoprecipitation, chromatin isolation by RNA purification, luciferase assay, and co-immunoprecipitation assay.

RESULTS

We demonstrated that circEHD2 was upregulated in RCC tissues and serum EVs of RCC patients with metastasis. Silencing circEHD2 inhibited tumor growth in vitro and in vivo. Mechanistic studies indicated that FUS RNA -binding protein (FUS) accelerated the cyclization of circEHD2, then circEHD2 interacts with tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein eta (YWHAH), which acts as a bridge to recruit circEHD2 and Yes1-associated transcriptional regulator (YAP) to the promoter of SRY-box transcription factor 9 (SOX9); this results in the sustained activation of SOX9. Heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2B1) regulates the package of circEHD2 into EVs, then EVs-circEHD2 transmits to fibroblasts, converting fibroblasts to cancer-associated fibroblasts (CAFs). Activated CAFs promote the metastasis of RCC by secreting pro-inflammatory cytokines such as IL-6. Furthermore, antisense oligonucleotides (ASOs) targeting circEHD2 exhibited a strong inhibition of tumor growth in vivo.

CONCLUSIONS

The circEHD2/YWHAH/YAP/SOX9 signaling pathway accelerates the growth of RCC. EVs-circEHD2 facilitates the metastasis of RCC by converting fibroblasts to CAFs. Our results suggest that EVs-circEHD2 may be a useful biomarker and therapeutic target for RCC.

Progress of regulatory RNA in small extracellular vesicles in colorectal cancer

Colorectal cancer (CRC) is the second most common malignant tumor of the gastrointestinal tract with the second highest mortality rate and the third highest incidence rate. Early diagnosis and treatment are important measures to reduce CRC mortality. Small extracellular vesicles (sEVs) have emerged as key mediators that facilitate communication between tumor cells and various other cells, playing a significant role in the growth, invasion, and metastasis of cancer cells. Regulatory RNAs have been identified as potential biomarkers for early diagnosis and prognosis of CRC, serving as crucial factors in promoting CRC cell proliferation, invasion and metastasis, angiogenesis, drug resistance, and immune cell differentiation. This review provides a comprehensive summary of the vital role of sEVs as biomarkers in CRC diagnosis and their potential application in CRC treatment, highlighting their importance as a promising avenue for further research and clinical translation.

Tumor Microenvironment Remodeling in Gastrointestinal Cancer: Role of miRNAs as Biomarkers of Tumor Invasion

Gastrointestinal (GI) cancers are the most frequent neoplasm, responsible for half of all cancer-related deaths. Metastasis is the leading cause of death from GI cancer; thus, studying the processes that regulate cancer cell migration is of paramount importance for the development of new therapeutic strategies. In this review, we summarize the mechanisms adopted by cancer cells to promote cell migration and the subsequent metastasis formation by highlighting the key role that tumor microenvironment components play in deregulating cellular pathways involved in these processes. We, therefore, provide an overview of the role of different microRNAs in promoting tumor metastasis and their role as potential biomarkers for the prognosis, monitoring, and diagnosis of GI cancer patients. Finally, we relate the possible use of nutraceuticals as a new strategy for targeting numerous microRNAs and different pathways involved in GI tumor invasiveness.

The role of miRNA in colorectal cancer diagnosis: A pilot study

Despite recent advances in diagnosis and treatment, colorectal cancer (CRC) remains the third most common cancer worldwide, and has both a poor prognosis and a high recurrence rate, thus indicating the need for new, sensitive and specific biomarkers. MicroRNAs (miRNAs/miRs) are important regulators of gene expression, which are involved in numerous biological processes implicated in tumorigenesis. The objective of the present study was to investigate the expression of miRNAs in plasma and tissue samples from patients with CRC, and to examine their potential as CRC biomarkers. Using reverse transcription-quantitative PCR, it was revealed that miR-29a, miR-101, miR-125b, miR-146a and miR-155 were dysregulated in the formalin-fixed paraffin-embedded tissues of patients with CRC, compared with the surrounding healthy tissue, and these miRNAs were associated with several pathological features of the tumor. Bioinformatics analysis of overlapping target genes identified AGE-RAGE signaling as a putative joint regulatory pathway. miR-146a was also upregulated in the plasma of patients with CRC, compared with the healthy control group, and had a fair discriminatory power (area under the curve, 0.7006), with 66.7% sensitivity and 77.8% specificity. To the best of our knowledge, this distinct five-miRNA deregulation pattern in tumor tissue, and upregulation of plasma miR-146a, were shown for the first time in patients with CRC; however, studies on larger patient cohorts are warranted to confirm their potential to be used as CRC diagnostic biomarkers.

Circ_0020256 induces fibroblast activation to drive cholangiocarcinoma development via recruitment of EIF4A3 protein to stabilize KLF4 mRNA

Cancer-associated fibroblasts (CAFs) are a kind of stromal cells in the cholangiocarcinoma (CCA) microenvironment, playing crucial roles in cancer development. However, the potential mechanisms of the interaction between CCA cells and CAFs remain obscure. This work investigated the role of circ_0020256 in CAFs activation. We proved circ_0020256 was up-regulated in CCA. High circ_0020256 expression facilitated TGF-β1 secretion from CCA cells, which activated CAFs via the phosphorylation of Smad2/3. Mechanistically, circ_0020256 recruited EIF4A3 protein to stabilize KLF4 mRNA and upregulate its expression, then KLF4 bound to TGF-β1 promoter and induced its transcription in CCA cells. KLF4 overexpression abrogated the inhibition of circ_0020256 silencing in TGF-β1/Smad2/3-induced CAFs activation. Furthermore, CCA cell growth, migration, and epithelial-mesenchymal transition were favored by CAFs-secreted IL-6 via autophagy inhibition. We also found circ_0020256 accelerated CCA tumor growth in vivo. In conclusion, circ_0020256 promoted fibroblast activation to facilitate CCA progression via EIF4A3/KLF4 pathway, providing a potential intervention for CCA progression.

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

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

Crosstalk between colorectal cancer cells and cancer-associated fibroblasts in the tumor microenvironment mediated by exosomal noncoding RNAs

Colorectal cancer (CRC) is a common malignant tumor of the digestive system, and its morbidity rates are increasing worldwide. Cancer-associated fibroblasts (CAFs), as part of the tumor microenvironment (TME), are not only closely linked to normal fibroblasts, but also can secrete a variety of substances (including exosomes) to participate in the regulation of the TME. Exosomes can play a key role in intercellular communication by delivering intracellular signaling substances (e.g., proteins, nucleic acids, non-coding RNAs), and an increasing number of studies have shown that non-coding RNAs of exosomal origin from CAFs are not only closely associated with the formation of the CRC microenvironment, but also increase the ability of CRC to grow in metastasis, mediate tumor immunosuppression, and are involved in the mechanism of drug resistance in CRC patients receiving. It is also involved in the mechanism of drug resistance after radiotherapy in CRC patients. In this paper, we review the current status and progress of research on CAFs-derived exosomal non-coding RNAs in CRC.

The application of extracellular vesicles in colorectal cancer metastasis and drug resistance: recent advances and trends

Colorectal cancer (CRC) has high incidence and mortality rates and is one of the most common cancers of the digestive tract worldwide. Metastasis and drug resistance are the main causes of cancer treatment failure. Studies have recently suggested extracellular vesicles (EVs) as a novel mechanism for intercellular communication. They are vesicular particles, which are secreted and released into biological fluids, such as blood, urine, milk, etc., by a variety of cells and carry numerous biologically active molecules, including proteins, nucleic acids, lipids, metabolites, etc. EVs play a crucial part in the metastasis and drug resistance of CRC by delivering cargo to recipient cells and modulating their behavior. An in-depth exploration of EVs might facilitate a comprehensive understanding of the biological behavior of CRC metastasis and drug resistance, which might provide a basis for developing therapeutic strategies. Therefore, considering the specific biological properties of EVs, researchers have attempted to explore their potential as next-generation delivery systems. On the other hand, EVs have also been demonstrated as biomarkers for the prediction, diagnosis, and presumed prognosis of CRC. This review focuses on the role of EVs in regulating the metastasis and chemoresistance of CRC. Moreover, the clinical applications of EVs are also discussed.

Paclitaxel and docetaxel resistance in prostate cancer: Molecular mechanisms and possible therapeutic strategies

Prostate cancer is among most malignant tumors around the world and this urological tumor can be developed as result of genomic mutations and their accumulation during progression towards advanced stage. Due to lack of specific symptoms in early stages of prostate cancer, most cancer patients are diagnosed in advanced stages that tumor cells display low response to chemotherapy. Furthermore, genomic mutations in prostate cancer enhance the aggressiveness of tumor cells. Docetaxel and paclitaxel are suggested as well-known compounds for chemotherapy of prostate tumor and they possess a similar function in cancer therapy that is based on inhibiting depolymerization of microtubules, impairing balance of microtubules and subsequent delay in cell cycle progression. The aim of current review is to highlight mechanisms of paclitaxel and docetaxel resistance in prostate cancer. When oncogenic factors such as CD133 display upregulation and PTEN as tumor-suppressor shows decrease in expression, malignancy of prostate tumor cells enhances and they can induce drug resistance. Furthermore, phytochemicals as anti-tumor compounds have been utilized in suppressing chemoresistance in prostate cancer. Naringenin and lovastatin are among the anti-tumor compounds that have been used for impairing progression of prostate tumor and enhancing drug sensitivity. Moreover, nanostructures such as polymeric micelles and nanobubbles have been utilized in delivery of anti-tumor compounds and decreasing risk of chemoresistance development. These subjects are highlighted in current review to provide new insight for reversing drug resistance in prostate cancer.

Extracellular Vesicles in Colorectal Cancer: From Tumor Growth and Metastasis to Biomarkers and Nanomedications

Colorectal cancer (CRC) is a leading public health concern due to its incidence and high mortality rates, highlighting the requirement of an early diagnosis. Evaluation of circulating extracellular vesicles (EVs) might constitute a noninvasive and reliable approach for CRC detection and for patient follow-up because EVs display the molecular features of the cells they originate. EVs are released by almost all cell types and are mainly categorized as exosomes originating from exocytosis of intraluminal vesicles from multivesicular bodies, ectosomes resulting from outward budding of the plasma membrane and apoptotic bodies' ensuing cell shrinkage. These vesicles play a critical role in intercellular communications during physiological and pathological processes. They facilitate CRC progression and premetastatic niche formation, and they enable transfer of chemotherapy resistance to sensitive cells through the local or remote delivery of their lipid, nucleic acid and protein content. On another note, their stability in the bloodstream, their permeation in tissues and their sheltering of packaged material make engineered EVs suitable vectors for efficient delivery of tracers and therapeutic agents for tumor imaging or treatment. Here, we focus on the physiopathological role of EVs in CRCs, their value in the diagnosis and prognosis and ongoing investigations into therapeutic approaches.

Cancer-associated fibroblast-derived exosome miR-181b-3p promotes the occurrence and development of colorectal cancer by regulating SNX2 expression

Tumor microenvironment (TME) (e.g., stromal cells) has been closely related to the pathological process of colorectal cancer (CRC). In TME, tumor-associated fibroblasts (CAFs) are the main stromal cells. The studies have showed that CAFs promoted tumor growth and metastasis in CRC and led to poor prognosis. Mounting evidence indicates that CAFs-mediated exosomes regulate the pathological process of neighboring tumor cells through the transmission of miRNAs. In our study, we aimed to explore the function of CAFs-derived exosome miR-181b-3p in CRC. First, the expression of miR-181b-3p in CRC was found to be up-regulated and its expression was dramatically up-regulated in CRC cells after co-incubation of CAFs-mediated exosomes with CRC cells. Then, it was found that the CAFs-derived exosomes were markedly enhanced the proliferation and migration of the CRC cells, and substantially reduced apoptosis. To elucidate the influence of CAFs-derived exosome miR-181b-3p on CRC, we overexpressed and knocked down the miR-181b-3p expression in CAFs, respectively. It was found that miR-181b-3p significantly increased the proliferation and migration of CRC cells. Furthermore, we conducted in vivo experiments. Finally, we demonstrated that CAF-derived exosome miR-181b-3p regulated sorting nexin 2 (SNX2) expression in CRC cells by bioinformatics prediction combined with luciferase reporter assay. Further cellular and animal experiments jointly elucidated that miR-181b-3p promoted the pathological process of CRC by SNX2 expression. In brief, our results demonstrated that CAFs-derived exosome miR-181b-3p promoted the pathogenesis of CRC by regulating SNX2 expression, which provides a novel idea for CRC treatment.

Modulating Effects of Cancer-Derived Exosomal miRNAs and Exosomal Processing by Natural Products

Cancer-derived exosomes exhibit sophisticated functions, such as proliferation, apoptosis, migration, resistance, and tumor microenvironment changes. Several clinical drugs modulate these exosome functions, but the impacts of natural products are not well understood. Exosome functions are regulated by exosome processing, such as secretion and assembly. The modulation of these exosome-processing genes can exert the anticancer and precancer effects of cancer-derived exosomes. This review focuses on the cancer-derived exosomal miRNAs that regulate exosome processing, acting on the natural-product-modulating cell functions of cancer cells. However, the role of exosomal processing has been overlooked in several studies of exosomal miRNAs and natural products. In this study, utilizing the bioinformatics database (miRDB), the exosome-processing genes of natural-product-modulated exosomal miRNAs were predicted. Consequently, several natural drugs that modulate exosome processing and exosomal miRNAs and regulate cancer cell functions are described here. This review sheds light on and improves our understanding of the modulating effects of exosomal miRNAs and their potential exosomal processing targets on anticancer treatments based on the use of natural products.

The Role of Extracellular Vesicles in Colorectal Cancer

Extracellular vesicles (EVs) are a class of spherical vesicles that are produced by active secretion of cells and encapsulated by phospholipid bilayers. In recent years, numerous studies have shown that EVs play pivotal roles in the regulation of intercellular communication between colorectal cancer (CRC) cells and target cells, and can regulate the proliferation, metastasis, and infiltration of tumor cells by regulating the microenvironment of tumor cells. EVs carry specific molecular substances in source CRC cells and are expected to serve as new molecular markers for the detection of cancers. This review highlights the current state of research and progress of potentially incorporating EVs in the diagnosis and treatment of CRC.

The Biological Effect of Small Extracellular Vesicles on Colorectal Cancer Metastasis

Colorectal cancer (CRC) is a malignancy that seriously threatens human health, and metastasis from CRC is a major cause of death and poor prognosis for patients. Studying the potential mechanisms of small extracellular vesicles (sEVs) in tumor development may provide new options for early and effective diagnosis and treatment of CRC metastasis. In this review, we systematically describe how sEVs mediate epithelial mesenchymal transition (EMT), reconfigure the tumor microenvironment (TME), modulate the immune system, and alter vascular permeability and angiogenesis to promote CRC metastasis. We also discuss the current difficulties in studying sEVs and propose new ideas.

Research advances and challenges in tissue-derived extracellular vesicles

Extracellular vesicles (EV) are vesicular vesicles with phospholipid bilayer, which are present in biological fluids and extracellular microenvironment. Extracellular vesicles serve as pivotal mediators in intercellular communication by delivering lipids, proteins, and RNAs to the recipient cells. Different from extracellular vesicles derived from biofluids and that originate from cell culture, the tissue derived extracellular vesicles (Ti-EVs) send us more enriched and accurate information of tissue microenvironment. Notably, tissue derived extracellular vesicles directly participate in the crosstalk between numerous cell types within microenvironment. Current research mainly focused on the extracellular vesicles present in biological fluids and cell culture supernatant, yet the studies on tissue derived extracellular vesicles are increasing due to the tissue derived extracellular vesicles are promising agents to reflect the occurrence and development of human diseases more accurately. In this review, we aimed to clarify the characteristics of tissue derived extracellular vesicles, specify the isolation methods and the roles of tissue derived extracellular vesicles in various diseases, including tumors. Moreover, we summarized the advances and challenges of tissue derived extracellular vesicles research.

Effects of Long Non-Coding RNAs Induced by the Gut Microbiome on Regulating the Development of Colorectal Cancer

Although an imbalanced gut microbiome is closely associated with colorectal cancer (CRC), how the gut microbiome affects CRC is not known. Long non-coding RNAs (lncRNAs) can affect important cellular functions such as cell division, proliferation, and apoptosis. The abnormal expression of lncRNAs can promote CRC cell growth, proliferation, and metastasis, mediating the effects of the gut microbiome on CRC. Generally, the gut microbiome regulates the lncRNAs expression, which subsequently impacts the host transcriptome to change the expression of downstream target molecules, ultimately resulting in the development and progression of CRC. We focused on the important role of the microbiome in CRC and their effects on CRC-related lncRNAs. We also reviewed the impact of the two main pathogenic bacteria, Fusobacterium nucleatum and enterotoxigenic Bacteroides fragilis, and metabolites of the gut microbiome, butyrate, and lipopolysaccharide, on lncRNAs. Finally, available therapies that target the gut microbiome and lncRNAs to prevent and treat CRC were proposed.

Intercellular crosstalk between cancer cells and cancer-associated fibroblasts via extracellular vesicles

Intercellular communication plays an important role in cancer initiation and progression through direct contact and indirect interactions, such as via secretory molecules. Cancer-associated fibroblasts (CAFs) are one of the principal components of such communication with cancer cells, modulating cancer metastasis and tumour mechanics and influencing angiogenesis, the immune system, and therapeutic resistance. Over the past few years, there has been a significant increase in research on extracellular vesicles (EVs) as regulatory agents in intercellular communication. EVs enable the transfer of functional molecules, including proteins, mRNAs and microRNAs (miRNAs), to recipient cells. Cancer cells utilize EVs to dictate the specific characteristics of CAFs within the tumour microenvironment, thereby promoting cancer progression. In response to such "education" by cancer cells, CAFs contribute to cancer progression via EVs. In this review, we summarize experimental data indicating the pivotal roles of EVs in intercellular communication between cancer cells and CAFs.

TGF-β Signaling in Metastatic Colorectal Cancer (mCRC): From Underlying Mechanism to Potential Applications in Clinical Development

Colorectal cancer (CRC) is a serious public health issue, and it has the leading incidence and mortality among malignant tumors worldwide. CRC patients with metastasis in the liver, lung or other distant sites always have poor prognosis. Thus, there is an urgent need to discover the underlying mechanisms of metastatic colorectal cancer (mCRC) and to develop optimal therapy for mCRC. Transforming growth factor-β (TGF-β) signaling plays a significant role in various physiologic and pathologic processes, and aberrant TGF-β signal transduction contributes to mCRC progression. In this review, we summarize the alterations of the TGF-β signaling pathway in mCRC patients, the functional mechanisms of TGF-β signaling, its promotion of epithelial-mesenchymal transition, its facilitation of angiogenesis, its suppression of anti-tumor activity of immune cells in the microenvironment and its contribution to stemness of CRC cells. We also discuss the possible applications of TGF-β signaling in mCRC diagnosis, prognosis and targeted therapies in clinical trials. Hopefully, these research advances in TGF-β signaling in mCRC will improve the development of new strategies that can be combined with molecular targeted therapy, immunotherapy and traditional therapies to achieve better efficacy and benefit mCRC patients in the near future.