Bone-marrow-derived cell-released extracellular vesicle miR-92a regulates hepatic pre-metastatic niche in lung cancer

mir-605-3p prevents liver premetastatic niche formation by inhibiting angiogenesis via decreasing exosomal nos3 release in gastric cancer

BACKGROUND

Cancer-induced pre-metastatic niches (PMNs) play a decisive role in promoting metastasis by facilitating angiogenesis in distant sites. Evidence accumulates suggesting that microRNAs (miRNAs) exert significant influence on angiogenesis during PMN formation, yet their specific roles and regulatory mechanisms in gastric cancer (GC) remain underexplored.

METHODS

miR-605-3p was identified through miRNA-seq and validated by qRT-PCR. Its correlation with the clinicopathological characteristics and prognosis was analyzed in GC. Functional assays were performed to examine angiogenesis both in vitro and in vivo. The related molecular mechanisms were elucidated using RNA-seq, immunofluorescence, transmission electron microscopy, nanoparticle tracking analysis, enzyme-linked immunosorbent assay, luciferase reporter assays and bioinformatics analysis.

RESULTS

miR-605-3p was screened as a candidate miRNA that may regulate angiogenesis in GC. Low expression of miR-605-3p is associated with shorter overall survival and disease-free survival in GC. miR-605-3p-mediated GC-secreted exosomes regulate angiogenesis by regulating exosomal nitric oxide synthase 3 (NOS3) derived from GC cells. Mechanistically, miR-605-3p reduced the secretion of exosomes by inhibiting vesicle-associated membrane protein 3 (VAMP3) expression and affects the transport of multivesicular bodies to the GC cell membrane. At the same time, miR-605-3p reduces NOS3 levels in exosomes by inhibiting the expression of intracellular NOS3. Upon uptake of GC cell-derived exosomal NOS3, human umbilical vein endothelial cells exhibited increased nitric oxide levels, which induced angiogenesis, established liver PMN and ultimately promoted the occurrence of liver metastasis. Furthermore, a high level of plasma exosomal NOS3 was clinically associated with metastasis in GC patients.

CONCLUSIONS

miR-605-3p may play a pivotal role in regulating VAMP3-mediated secretion of exosomal NOS3, thereby affecting the formation of GC PMN and thus inhibiting GC metastasis.

Evolving landscape of treatments targeting the microenvironment of liver metastases in non-small cell lung cancer

ABSTRACT

Liver metastases (LMs) are common in lung cancer. Despite substantial advances in diagnosis and treatment, the survival rate of patients with LM remains low as the immune-suppressive microenvironment of the liver allows tumor cells to evade the immune system. The impact of LMs on the outcomes of immune checkpoint inhibitors in patients with solid tumors has been the main focus of recent translational and clinical research. Growing evidence indicates that the hepatic microenvironment delivers paracrine and autocrine signals from non-parenchymal and parenchymal cells. Overall, these microenvironments create pre- and post-metastatic conditions for the progression of LMs. Herein, we reviewed the epidemiology, physiology, pathology and immunology, of LMs associated with non-small cell lung cancer and the role and potential targets of the liver microenvironment in LM in each phase of metastasis. Additionally, we reviewed the current treatment strategies and challenges that should be overcome in preclinical and clinical investigations. These approaches target liver elements as the basis for future clinical trials, including combinatorial interventions reported to resolve hepatic immune suppression, such as immunotherapy plus chemotherapy, immunotherapy plus radiotherapy, immunotherapy plus anti-angiogenesis therapy, and surgical resection.

Extracellular vesicles as tools and targets in therapy for diseases

Extracellular vesicles (EVs) are nano-sized, membranous structures secreted into the extracellular space. They exhibit diverse sizes, contents, and surface markers and are ubiquitously released from cells under normal and pathological conditions. Human serum is a rich source of these EVs, though their isolation from serum proteins and non-EV lipid particles poses challenges. These vesicles transport various cellular components such as proteins, mRNAs, miRNAs, DNA, and lipids across distances, influencing numerous physiological and pathological events, including those within the tumor microenvironment (TME). Their pivotal roles in cellular communication make EVs promising candidates for therapeutic agents, drug delivery systems, and disease biomarkers. Especially in cancer diagnostics, EV detection can pave the way for early identification and offers potential as diagnostic biomarkers. Moreover, various EV subtypes are emerging as targeted drug delivery tools, highlighting their potential clinical significance. The need for non-invasive biomarkers to monitor biological processes for diagnostic and therapeutic purposes remains unfulfilled. Tapping into the unique composition of EVs could unlock advanced diagnostic and therapeutic avenues in the future. In this review, we discuss in detail the roles of EVs across various conditions, including cancers (encompassing head and neck, lung, gastric, breast, and hepatocellular carcinoma), neurodegenerative disorders, diabetes, viral infections, autoimmune and renal diseases, emphasizing the potential advancements in molecular diagnostics and drug delivery.

The Role of Osteocytes in Pre-metastatic Niche Formation

PURPOSE OF REVIEW

The formation of a pre-metastatic niche (PMN), in which primary cancer cells prime the distant site to be favorable to their engraftment and survival, may help explain the strong osteotropism observed in multiple cancers, such as breast and prostate. PMN formation, which includes extracellular matrix remodeling, increased angiogenesis and vascular permeability, enhanced bone marrow-derived cell recruitment and immune suppression, has mostly been described in soft tissues. In this review, we summarize current literature of PMN formation in bone. We also present evidence of a potential role for osteocytes to be the primary mediators of PMN development.

RECENT FINDINGS

Osteocytes regulate the bone microenvironment in myriad ways beyond canonical bone tissue remodeling, including changes that contribute to PMN formation. Perilacunar tissue remodeling, which has been observed in both bone and non-bone metastatic cancers, is a potential mechanism by which osteocyte-cancer cell signaling stimulates changes to the bone microenvironment. Osteocytes also protect against endothelial permeability, including that induced by cancer cells, in a loading-mediated process. Finally, osteocytes are potent regulators of cells within the bone marrow, including progenitors and immune cells, and might be involved in this aspect of PMN formation. Osteocytes should be examined for their role in PMN formation.

Extracellular matrix remodeling in the tumor immunity

The extracellular matrix (ECM) is a significant constituent of tumors, fulfilling various essential functions such as providing mechanical support, influencing the microenvironment, and serving as a reservoir for signaling molecules. The abundance and degree of cross-linking of ECM components are critical determinants of tissue stiffness. In the process of tumorigenesis, the interaction between ECM and immune cells within the tumor microenvironment (TME) frequently leads to ECM stiffness, thereby disrupting normal mechanotransduction and promoting malignant progression. Therefore, acquiring a thorough comprehension of the dysregulation of ECM within the TME would significantly aid in the identification of potential therapeutic targets for cancer treatment. In this regard, we have compiled a comprehensive summary encompassing the following aspects: (1) the principal components of ECM and their roles in malignant conditions; (2) the intricate interaction between ECM and immune cells within the TME; and (3) the pivotal regulators governing the onco-immune response in ECM.

The extracellular matrix as hallmark of cancer and metastasis: From biomechanics to therapeutic targets

The extracellular matrix (ECM) is essential for cell support during homeostasis and plays a critical role in cancer. Although research often concentrates on the tumor's cellular aspect, attention is growing for the importance of the cancer-associated ECM. Biochemical and physical ECM signals affect tumor formation, invasion, metastasis, and therapy resistance. Examining the tumor microenvironment uncovers intricate ECM dysregulation and interactions with cancer and stromal cells. Anticancer therapies targeting ECM sensors and remodelers, including integrins and matrix metalloproteinases, and ECM-remodeling cells, have seen limited success. This review explores the ECM's role in cancer and discusses potential therapeutic strategies for cell-ECM interactions.

Effects of extracellular vesicle-derived noncoding RNAs on pre-metastatic niche and tumor progression

A pre-metastatic niche (PMN) is a protective microenvironment that facilitates the colonization of disseminating tumor cells in future metastatic organs. Extracellular vesicles (EVs) play a role in intercellular communication by delivering cargoes, such as noncoding RNAs (ncRNAs). The pivotal role of extracellular vesicle-derived noncoding RNAs (EV-ncRNAs) in the PMN has attracted increasing attention. In this review, we summarized the effects of EV-ncRNAs on the PMN in terms of immunosuppression, vascular permeability and angiogenesis, inflammation, metabolic reprogramming, and fibroblast alterations. In particular, we provided a comprehensive overview of the effects of EV-ncRNAs on the PMN in different cancers. Finally, we discussed the promising clinical applications of EV-ncRNAs, including their potential as diagnostic and prognostic markers and therapeutic targets.

Tumour-derived exosomes in liver metastasis: A Pandora's box

The liver is a common secondary metastasis site of many malignant tumours, such as the colorectum, pancreas, stomach, breast, prostate, and lung cancer. The clinical management of liver metastases is challenging because of their strong heterogeneity, rapid progression, and poor prognosis. Now, exosomes, small membrane vesicles that are 40-160 nm in size, are released by tumour cells, namely, tumour-derived exosomes (TDEs), and are being increasingly studied because they can retain the original characteristics of tumour cells. Cell-cell communication via TDEs is pivotal for liver pre-metastatic niche (PMN) formation and liver metastasis; thus, TDEs can provide a theoretical basis to intensively study the potential mechanisms of liver metastasis and new insights into the diagnosis and treatment of liver metastasis. Here, we systematically review current research progress about the roles and possible regulatory mechanisms of TDE cargos in liver metastasis, focusing on the functions of TDEs in liver PMN formation. In addition, we discuss the clinical utility of TDEs in liver metastasis, including TDEs as potential biomarkers, and therapeutic approaches for future research reference in this field.

The role of extracellular vesicles in non-small-cell lung cancer, the unknowns, and how new approach methodologies can support new knowledge generation in the field

Extracellular vesicles (EVs) are nanosized particles released from most human cell types that contain a variety of cargos responsible for mediating cell-to-cell and organ-to-organ communications. Current knowledge demonstrates that EVs also play critical roles in many aspects of the progression of Non-Small-Cell Lung Cancer (NSCLC). Their roles range from increasing proliferative signalling to inhibiting apoptosis, promoting cancer metastasis, and modulating the tumour microenvironment to support cancer development. However, due to the limited availability of patient samples, intrinsic inter-species differences between human and animal EV biology, and the complex nature of EV interactions in vivo, where multiple cell types are present and several events occur simultaneously, the use of conventional preclinical and clinical models has significantly hindered reaching conclusive results. This review discusses the biological roles that EVs are currently known to play in NSCLC and identifies specific challenges in advancing today's knowledge. It also describes the NSCLC models that have been used to define currently-known EV functions, the limitations associated with their use in this field, and how New Approach Methodologies (NAMs), such as microfluidic platforms, organoids, and spheroids, can be used to overcome these limitations, effectively supporting future exciting discoveries in the NSCLC field and the potential clinical exploitation of EVs.

Cancer-associated fibroblasts: Key criminals of tumor pre-metastatic niche

Cancer-associated fibroblasts (CAFs) are abundant and important components of the tumour mesenchyme, and have been extensively studied for their role in primary tumours. CAFs provide biomechanical support for tumour cells and play key roles in immunosuppression and tumour metastasis. CAFs can promote epithelial-mesenchymal transition (EMT) of the primary tumour by secreting extracellular vesicles (EVs), increasing adhesion to tumour cells, remodelling the extracellular matrix (ECM) of the primary tumour, and changing its mechanical stiffness, which provides a pathway for tumour metastasis. Moreover, CAFs can form cell clusters with circulating tumour cells (CTCs) to help them resist blood shear forces and achieve colonisation of distant host organs. Recent studies have revealed their roles in pre-metastatic niche (PMN) formation and prevention. In this review, we discuss the role of CAFs in PMN formation and therapeutic interventions targeting PMN and CAFs to prevent metastasis.

Context-specific regulation of extracellular vesicle biogenesis and cargo selection

To coordinate, adapt and respond to biological signals, cells convey specific messages to other cells. An important aspect of cell-cell communication involves secretion of molecules into the extracellular space. How these molecules are selected for secretion has been a fundamental question in the membrane trafficking field for decades. Recently, extracellular vesicles (EVs) have been recognized as key players in intercellular communication, carrying not only membrane proteins and lipids but also RNAs, cytosolic proteins and other signalling molecules to recipient cells. To communicate the right message, it is essential to sort cargoes into EVs in a regulated and context-specific manner. In recent years, a wealth of lipidomic, proteomic and RNA sequencing studies have revealed that EV cargo composition differs depending upon the donor cell type, metabolic cues and disease states. Analyses of distinct cargo 'fingerprints' have uncovered mechanistic linkages between the activation of specific molecular pathways and cargo sorting. In addition, cell biology studies are beginning to reveal novel biogenesis mechanisms regulated by cellular context. Here, we review context-specific mechanisms of EV biogenesis and cargo sorting, focusing on how cell signalling and cell state influence which cellular components are ultimately targeted to EVs.

Emerging diversity in extracellular vesicles and their roles in cancer

Extracellular vesicles have undergone a paradigm shift from being considered as 'waste bags' to being central mediators of cell-to-cell signaling in homeostasis and several pathologies including cancer. Their ubiquitous nature, ability to cross biological barriers, and dynamic regulation during changes in pathophysiological state of an individual not only makes them excellent biomarkers but also critical mediators of cancer progression. This review highlights the heterogeneity in extracellular vesicles by discussing emerging subtypes, such as migrasomes, mitovesicles, and exophers, as well as evolving components of extracellular vesicles such as the surface protein corona. The review provides a comprehensive overview of our current understanding of the role of extracellular vesicles during different stages of cancer including cancer initiation, metabolic reprogramming, extracellular matrix remodeling, angiogenesis, immune modulation, therapy resistance, and metastasis, and highlights gaps in our current knowledge of extracellular vesicle biology in cancer. We further provide a perspective on extracellular vesicle-based cancer therapeutics and challenges associated with bringing them to the clinic.

Involvement of ACACA (acetyl-CoA carboxylase α) in the lung pre-metastatic niche formation in breast cancer by senescence phenotypic conversion in fibroblasts

BACKGROUND

Reprogramming of metabolism is strongly associated with the development of cancer. However, the role of metabolic reprogramming in the remodeling of pre-metastatic niche (PMN), a key step in metastasis, is still unknown. We aimed to investigate the metabolic alternation during lung PMN formation in breast cancer.

METHODS

We assessed the transcriptomes and lipidomics of lung of MMTV-PyVT mice by microarray and liquid chromatography-tandem mass mass spectrometry before lung metastasis. The validation of gene or protein expressions was performed by quantitative real-time polymerase chain reaction or immunoblot and immunohistochemistry respectively. The lung fibroblasts were isolated from mice and then co-cultured with breast cancer to identify the influence of cancer on the change of lung fibroblasts in PMN.

RESULTS

We demonstrated changes in the lipid profile and several lipid metabolism genes in the lungs of breast cancer-bearing MMTV-PyVT mice before cancer spreading. The expression of ACACA (acetyl-CoA carboxylase α) was downregulated in the lung fibroblasts, which contributed to changes in acetylation of protein's lysine residues and the synthesis of fatty acid. The downregulation of ACACA in lung fibroblasts triggered a senescent and inflammatory phenotypic shift of lung fibroblasts in both in vivo and in vitro models. The senescence-associated secretory phenotype of lung fibroblasts enabled the recruitment of immunosuppressive granulocytic myeloid-derived suppressor cells into the lungs through the production of CXCL1 in the lungs. Knock-in of ACACA prevented lung metastasis in the MMTV-PyVT mouse model, further supporting that ACACA was involved in the remodeling of the lung PMN.

CONCLUSIONS

Taken together, these data revealed a mechanism by which ACACA downregulation directed the formation of an immunosuppressive lung PMN in breast cancer.

Non-Coding RNAs Derived from Extracellular Vesicles Promote Pre-Metastatic Niche Formation and Tumor Distant Metastasis

Metastasis is a critical stage of tumor progression, a crucial challenge of clinical therapy, and a major cause of tumor patient death. Numerous studies have confirmed that distant tumor metastasis is dependent on the formation of pre-metastatic niche (PMN). Recent studies have shown that extracellular vesicles (EVs) play an important role in PMN formation. The non-coding RNAs (ncRNAs) derived from EVs mediate PMN formation and tumor-distant metastasis by promoting an inflammatory environment, inhibiting anti-tumor immune response, inducing angiogenesis and permeability, and by microenvironmental reprogramming. Given the stability and high abundance of ncRNAs carried by EVs in body fluids, they have great potential for application in tumor diagnosis as well as targeted interventions. This review focuses on the mechanism of ncRNAs derived from EVs promoting tumor PMN formation and distant metastasis to provide a theoretical reference for strategies to control tumor metastasis.

Extracellular matrix remodeling in tumor progression and immune escape: from mechanisms to treatments

The malignant tumor is a multi-etiological, systemic and complex disease characterized by uncontrolled cell proliferation and distant metastasis. Anticancer treatments including adjuvant therapies and targeted therapies are effective in eliminating cancer cells but in a limited number of patients. Increasing evidence suggests that the extracellular matrix (ECM) plays an important role in tumor development through changes in macromolecule components, degradation enzymes and stiffness. These variations are under the control of cellular components in tumor tissue via the aberrant activation of signaling pathways, the interaction of the ECM components to multiple surface receptors, and mechanical impact. Additionally, the ECM shaped by cancer regulates immune cells which results in an immune suppressive microenvironment and hinders the efficacy of immunotherapies. Thus, the ECM acts as a barrier to protect cancer from treatments and supports tumor progression. Nevertheless, the profound regulatory network of the ECM remodeling hampers the design of individualized antitumor treatment. Here, we elaborate on the composition of the malignant ECM, and discuss the specific mechanisms of the ECM remodeling. Precisely, we highlight the impact of the ECM remodeling on tumor development, including proliferation, anoikis, metastasis, angiogenesis, lymphangiogenesis, and immune escape. Finally, we emphasize ECM "normalization" as a potential strategy for anti-malignant treatment.

The role of microRNAs in the modulation of cancer-associated fibroblasts activity during pancreatic cancer pathogenesis

Pancreatic ductal adenocarcinoma (PDAC) is the deadliest of the common cancers. A major hallmark of PDAC is an abundant and dense fibrotic stroma, the result of a disproportionate deposition of extracellular matrix (ECM) proteins. Cancer-associated fibroblasts (CAFs) are the main mediators of PDAC desmoplasia. CAFs represent a heterogenous group of activated fibroblasts with different origins and activation mechanisms. microRNAs (miRNAs) are small non-coding RNAs with critical activity during tumour development and resistance to chemotherapy. Increasing evidence has revealed that miRNAs play a relevant role in the differentiation of normal fibroblasts into CAFs in PDAC. In this review, we discuss recent findings on the role of miRNAs in the activation of CAFs during the progression of PDAC and its response to therapy, as well as the potential role that PDAC-derived exosomal miRNAs may play in the activation of hepatic stellate cells (HSCs) and formation of liver metastasis. Since targeting of CAF activation may be a viable strategy for PDAC therapy, and miRNAs have emerged as potential therapeutic targets, understanding the biology underpinning miRNA-mediated tumour cell-CAF interactions is an important component in guiding rational approaches to treating this deadly disease.

The metastatic niche formation: focus on extracellular vesicle-mediated dialogue between lung cancer cells and the microenvironment

Lung cancer is the deadliest cancer in the world, with the majority of patients presenting with advanced or metastatic disease at first diagnosis. The lungs are also one of the most common sites of metastasis from lung cancer and other tumors. Understanding the mechanisms that regulate metastasis formation from primary lung cancer and in the lungs is therefore fundamental unmet clinical need. One of the first steps during the establishment of lung cancer metastases includes the formation of the pre-metastatic niche (PMN) at distant organs, which may occur even during the early phases of cancer development. The PMN is established through intricate cross-talk between primary tumor-secreted factors and stromal components at distant sites. Mechanisms controlling primary tumor escape and seeding of distant organs rely on specific properties of tumor cells but are also tightly regulated by interactions with stromal cells at the metastatic niche that finally dictate the success of metastasis establishment. Here, we summarize the mechanisms underlying pre-metastatic niche formation starting from how lung primary tumor cells modulate distant sites through the release of several factors, focusing on Extracellular Vesicles (EVs). In this context, we highlight the role of lung cancer-derived EVs in the modulation of tumor immune escape. Then, we illustrate the complexity of Circulating Tumor Cells (CTCs) that represent the seeds of metastasis and how interactions with stromal and immune cells can help their metastatic dissemination. Finally, we evaluate the contribution of EVs in dictating metastasis development at the PMN through stimulation of proliferation and control of disseminated tumor cell dormancy. Overall, we present an overview of different steps in the lung cancer metastatic cascade, focusing on the EV-mediated interactions between tumor cells and stromal/immune cells.

An Overview of Epithelial-to-Mesenchymal Transition and Mesenchymal-to-Epithelial Transition in Canine Tumors: How Far Have We Come?

Historically, pre-clinical and clinical studies in human medicine have provided new insights, pushing forward the contemporary knowledge. The new results represented a motivation for investigators in specific fields of veterinary medicine, who addressed the same research topics from different perspectives in studies based on experimental and spontaneous animal disease models. The study of different pheno-genotypic contexts contributes to the confirmation of translational models of pathologic mechanisms. This review provides an overview of EMT and MET processes in both human and canine species. While human medicine rapidly advances, having a large amount of information available, veterinary medicine is not at the same level. This situation should provide motivation for the veterinary medicine research field, to apply the knowledge on humans to research in pets. By merging the knowledge of these two disciplines, better and faster results can be achieved, thus improving human and canine health.

Role of the Hypoxic-Secretome in Seed and Soil Metastatic Preparation

During tumor growth, the delivery of oxygen to cells is impaired due to aberrant or absent vasculature. This causes an adaptative response that activates the expression of genes that control several essential processes, such as glycolysis, neovascularization, immune suppression, and the cancer stemness phenotype, leading to increased metastasis and resistance to therapy. Hypoxic tumor cells also respond to an altered hypoxic microenvironment by secreting vesicles, factors, cytokines and nucleic acids that modify not only the immediate microenvironment but also organs at distant sites, allowing or facilitating the attachment and growth of tumor cells and contributing to metastasis. Hypoxia induces the release of molecules of different biochemical natures, either secreted or inside extracellular vesicles, and both tumor cells and stromal cells are involved in this process. The mechanisms by which these signals that can modify the premetastatic niche are sent from the primary tumor site include changes in the extracellular matrix, recruitment and activation of different stromal cells and immune or nonimmune cells, metabolic reprogramming, and molecular signaling network rewiring. In this review, we will discuss how hypoxia might alter the premetastatic niche through different signaling molecules.

Extracellular vesicles and particles impact the systemic landscape of cancer

Intercellular cross talk between cancer cells and stromal and immune cells is essential for tumor progression and metastasis. Extracellular vesicles and particles (EVPs) are a heterogeneous class of secreted messengers that carry bioactive molecules and that have been shown to be crucial for this cell-cell communication. Here, we highlight the multifaceted roles of EVPs in cancer. Functionally, transfer of EVP cargo between cells influences tumor cell growth and invasion, alters immune cell composition and function, and contributes to stromal cell activation. These EVP-mediated changes impact local tumor progression, foster cultivation of pre-metastatic niches at distant organ-specific sites, and mediate systemic effects of cancer. Furthermore, we discuss how exploiting the highly selective enrichment of molecules within EVPs has profound implications for advancing diagnostic and prognostic biomarker development and for improving therapy delivery in cancer patients. Altogether, these investigations into the role of EVPs in cancer have led to discoveries that hold great promise for improving cancer patient care and outcome.

The Hepatic Pre-Metastatic Niche

Simple Summary

The pre-metastatic niche is a recently established concept that could lead to targeted therapies that prevent metastasis before ever occurring. Considering that 90% of cancer mortality results from metastasis, the PMN is thus a salient opportunity for intervention. The purpose of the current review is to cover what is known specifically about the hepatic pre-metastatic niche, a topic that has garnered increasing research focus within the last decade. We discuss the methods of communication between primary tumors and the liver, the involved cell populations, the key changes within liver tissue, and perspectives on the future of the field.

Abstract

Primary tumors can communicate with the liver to establish a microenvironment that favors metastatic colonization prior to dissemination, forming what is termed the “pre-metastatic niche” (PMN). Through diverse signaling mechanisms, distant malignancies can both influence hepatic cells directly as well as recruit immune cells into the PMN. The result is a set of changes within the hepatic tissue that increase susceptibility of tumor cell invasion and outgrowth upon dissemination. Thus, the PMN offers a novel step in the traditional metastatic cascade that could offer opportunities for clinical intervention. The involved signaling molecules also offer promise as biomarkers. Ultimately, while the existence of the hepatic PMN is well-established, continued research effort and use of innovative models are required to reach a functional knowledge of PMN mechanisms that can be further targeted.

Circulating salivary and serum miRNA-182, 320a, 375 and 503 expression levels in type 2 diabetes

Aim

Early-stage diagnosis of diabetes through non-invasive and diagnostic biofluid-like saliva has become a very popular approach to facilitate future preventive interventions and improve patient care. Meanwhile, the alteration of small non-coding RNA in human fluids has been suggested as a probable precedent for the early stages of diabetes.

Methods

In the present study, we checked the expression of miR-320a, 182-5p, 503, and 375 by using quantitative PCR in both stimulated and unstimulated saliva and blood samples of 40 adult patients with type-2 diabetes compared to 40 healthy individuals. In addition, we have sought to understand the possibility that miRNAs could provide new information about the status of type 2 diabetes in salivary samples beyond what can now be identified from blood samples and link their expression to the presence of clinically relevant risk factors. For this purpose, we have used a set of multivariate models.

Results

The results showed that three miRNAs were more highly expressed in patients with type 2 diabetes, while miR-320-a was down-regulated in those patients compared to healthy subjects. Furthermore, the data showed that miR-320a was the most reliable predictor for distinguishing diabetic patients from healthy subjects, with AUCs of 0.997, 0.97, and 0.99 (97.4% sensitivity and 100% specificity, p = 0.001) for serum, unstimulated, and stimulated saliva samples, respectively.

Conclusions

Interestingly, the results of this study indicated that the amount of four miRNAs expressed in stimulated saliva was the same as in serum samples, which could conclude that specific miR-320a and 503 in stimulated saliva may introduce credible, non-invasive, and diagnostic biomarkers that can be used to monitor diabetic patients' status, while there is a need to design more research studies to confirm these findings.

Characterization of the Oncogenic Potential of Eukaryotic Initiation Factor 4A1 in Lung Adenocarcinoma via Cell Cycle Regulation and Immune Microenvironment Reprogramming

Lung adenocarcinoma (LUAD) is a common type of lung cancer. Although the diagnosis and treatment of LUAD have significantly improved in recent decades, the survival for advanced LUAD is still poor. It is necessary to identify more targets for developing potential agents against LUAD. This study explored the dysregulation of translation initiation factors, specifically eukaryotic initiation factors 4A1 (EIF4A1) and EIF4A2, in developing LUAD, as well as their underlying mechanisms. We found that the expression of EIF4A1, but not EIF4A2, was higher in tumor tissue and associated with poor clinical outcomes in LUAD patients. Elevated expression of EIF4H with poor prognosis may potentiate the oncogenic role of EIF4A1. Functional enrichment analysis revealed that upregulation of EIF4A1 was related to cell cycle regulation and DNA repair. The oncogenic effect of EIF4A1 was further elucidated by Gene Set Variation Analysis (GSVA). The GSVA score of the gene set positively correlated with EIF4A1 was higher in tumors and significantly associated with worse survival. In the meantime, gene set enrichment analysis (GSEA) also indicated that elevated EIF4A1 expression in LUAD patients was associated with a decreased infiltration score for immune cells by reducing anticancer immune cell types and recruiting immunosuppressive cells. Consistent with the results, the GSVA score of genes whose expression was negatively correlated with EIF4A1 was lower in the tumor tissue of LUAD cases with worse clinical outcomes and was strongly associated with the disequilibrium of anti-cancer immunity by recruiting anticancer immune cells. Based on the results from the present study, we hypothesize that the dysregulation of EIF4A1 might be involved in the pathophysiology of LUAD development by promoting cancer growth and changing the tumor immune microenvironment. This can be used to develop potential diagnostic biomarkers or therapeutic targets for LUAD.

Myc manipulates the miRNA content and biologic functions of small cell lung cancer cell-derived small extracellular vesicles

BACKGROUND

MYC genes are amplified/overexpressed in 20% of SCLCs, showing that Myc and Myc-dependent cellular mechanisms are strong candidates as therapeutic targets in SCLC. Small extracellular vesicles support the carcinogenesis process by acting as messengers delivering nucleic acids and proteins-moreover, no reports associate Myc and the functional effect of small extracellular vesicles in small cell lung cancer.

METHODS AND RESULTS

After the effects of small extracellular vesicles (sEVs) obtained from H82 and H209 cells on HUVEC and MRC-5 cells were observed, the Myc-dependent effect of the sEVs on oncogenic potentials was further evaluated by manipulating Myc expression via lentiviral vectors in H82 and H209 cells. Then, small extracellular vesicles of Myc-manipulated SCLC cells were isolated using sEVs isolation reagents. Finally, HUVEC and MRC5 cells were treated with SCLC-derived small extracellular vesicles. Cellular activity of recipient normal lung cells was investigated by cell growth assay, wound healing assay, and transwell assay. miRNA composition changes in small extracellular vesicles and SCLC cells were investigated using miRNA microarray and QRT-PCR assay. Our results indicated that normal lung cells treated with SCLC-derived small extracellular vesicles had higher proliferation, migration capability than non-treated counterparts. Additionally, after investigating the potential effects of small extracellular vesicles derived from Myc-dysregulated SCLC cell lines, we further evaluated the Myc-dependent miRNA composition in the small extracellular vesicles. The present study revealed that Myc regulates hsa-miR-7, hsa-miR-9, hsa-miR-125b, hsa-miR-181a_2, hsa-miR-455, hsa-miR-642, and hsa-miR-4417 expressions in SCLC cell lines, not only in cellular but also in exosomal content.

CONCLUSIONS

Small extracellular vesicles and MYC are essential targets for therapeutic strategy in SCLC. Our study revealed that the expression level of MYC can affect the function of sEVs and encapsulate the miRNA composition in SCLC. Besides, small extracellular vesicles derived from SCLC cells can modulate normal lung cells.

Extracellular Vesicles and Transforming Growth Factor β Signaling in Cancer

Complexity in mechanisms that drive cancer development and progression is exemplified by the transforming growth factor β (TGF-β) signaling pathway, which suppresses early-stage hyperplasia, yet assists aggressive tumors to achieve metastasis. Of note, several molecules, including mRNAs, non-coding RNAs, and proteins known to be associated with the TGF-β pathway have been reported as constituents in the cargo of extracellular vesicles (EVs). EVs are secreted vesicles delimited by a lipid bilayer and play critical functions in intercellular communication, including regulation of the tumor microenvironment and cancer development. Thus, this review aims at summarizing the impact of EVs on TGF-β signaling by focusing on mechanisms by which EV cargo can influence tumorigenesis, metastatic spread, immune evasion and response to anti-cancer treatment. Moreover, we emphasize the potential of TGF-β-related molecules present in circulating EVs as useful biomarkers of prognosis, diagnosis, and prediction of response to treatment in cancer patients.

Cancer metabolism and tumor microenvironment: fostering each other?

The changes associated with malignancy are not only in cancer cells but also in environment in which cancer cells live. Metabolic reprogramming supports tumor cell high demand of biogenesis for their rapid proliferation, and helps tumor cell to survive under certain genetic or environmental stresses. Emerging evidence suggests that metabolic alteration is ultimately and tightly associated with genetic changes, in particular the dysregulation of key oncogenic and tumor suppressive signaling pathways. Cancer cells activate HIF signaling even in the presence of oxygen and in the absence of growth factor stimulation. This cancer metabolic phenotype, described firstly by German physiologist Otto Warburg, insures enhanced glycolytic metabolism for the biosynthesis of macromolecules. The conception of metabolite signaling, i.e., metabolites are regulators of cell signaling, provides novel insights into how reactive oxygen species (ROS) and other metabolites deregulation may regulate redox homeostasis, epigenetics, and proliferation of cancer cells. Moreover, the unveiling of noncanonical functions of metabolic enzymes, such as the moonlighting functions of phosphoglycerate kinase 1 (PGK1), reassures the importance of metabolism in cancer development. The metabolic, microRNAs, and ncRNAs alterations in cancer cells can be sorted and delivered either to intercellular matrix or to cancer adjacent cells to shape cancer microenvironment via media such as exosome. Among them, cancer microenvironmental cells are immune cells which exert profound effects on cancer cells. Understanding of all these processes is a prerequisite for the development of a more effective strategy to contain cancers.

Salivary microRNA-126 and 135a: a potentially non-invasive diagnostic biomarkers of type- 2 diabetes

Purpose

Emerging of miRNAs have illustrated the new mechanistic layer to regulate type 2 diabetes process and suggests a possible role of these RNAs in this defect. Thus, we designed this study to improve our understanding of salivary miRNA-126 and 135a expression utility as an easy of collection and non-invasive way in diabetic patients instead of blood sample.

Methods

This case-control study was done on T₂D (n = 40) and healthy individuals (n = 40). The level of biochemical parameters were determined by enzymatic methods as well as glycosylated hemoglobin (HbA1c) was measured by immunoturbidimetry. We used the pooled whole stimulated saliva sample from cases and controls to assess the differentiation expression of miRNA 126 and 135-a with quantitative RT-PCR method. Unpaired Student's t test, Pearson's correlation coefficient and Receiver Operating Characteristic (ROC) analysis were used.

Results

A correlation was observed between the level of HbA1c, glucose and lipid profiles (TG, TC, and LDL) in serum and whole stimulated saliva samples in T₂D patients compared to control (p < 0.001). miR-135a expression was considerably higher by 4.7-fold in T₂D compared to the control group (1.8-fold) (p < 0.001) while the miR126 expression was significantly decreased by 3.9-fold in T₂D compared to the controls (6.3-fold) (p < 0.001).

Conclusions

The results of this case and control study showed that miR-135a and miR126 expression in saliva fluid as a reliable biomarkers and non-invasive approach in combination by change of lipid profiles, glucose and HbA1c may be used to monitor diabetic and non-diabetic patients, while further research is needed to investigate the relationship of these salivary miRNAs (miR135a, miR126) levels change on shifting the levels of clinical laboratory outcomes.

miR-150-5p-Containing Extracellular Vesicles Are a New Immunoregulator That Favor the Progression of Lung Cancer in Hypoxic Microenvironments by Altering the Phenotype of NK Cells

Natural killer (NKs) cells are cytotoxic effector cells, which can modulate tumor metastasis according to their function; however, the role of NK cells in lung cancer has not been extensively investigated. In this study, we determined the functional profiles of NK cells in a hypoxic tumor microenvironment (TME) of lung cancer. We revealed CD226 downregulation and functional repression of NK cells after hypoxic lung cancer priming and we then investigated their interaction with extracellular vesicles (EVs) and miR-150-5p. We also found that NK cells from lung cancer patients had lower expression of CD226 on their surface and exhibited a pro-inflammatory, pro-angiogenic and tumorigenesis phenotype by expressing VEGF, CXCL1, CXCL8, S100A8 and MMPs. Moreover, inhibition of miR-150 improved tumor surveillance by reversing CD226 expression and subsequently reinstating cytotoxic NK cell activity in an animal model. Our study introduces a new scenario for the pro-inflammatory and pro-angiogenic activities of NK cells in the hypoxic TME in lung cancer.

Extracellular Vesicles in Lung Cancer Metastasis and Their Clinical Applications

Extracellular vesicles (EVs) are heterogenous membrane-encapsulated vesicles secreted by every cell into the extracellular environment. EVs carry bioactive molecules, including proteins, lipids, DNA, and different RNA forms, which can be internalized by recipient cells, thus altering their biological characteristics. Given that EVs are commonly found in most body fluids, they have been widely described as mediators of communication in several physiological and pathological processes, including cancer. Moreover, their easy detection in biofluids makes them potentially useful candidates as tumor biomarkers. In this manuscript, we review the current knowledge regarding EVs and non-coding RNAs and their role as drivers of the metastatic process in lung cancer. Furthermore, we present the most recent applications for EVs and non-coding RNAs as cancer therapeutics and their relevance as clinical biomarkers.

MIRLET7BHG promotes hepatocellular carcinoma progression by activating hepatic stellate cells through exosomal SMO to trigger Hedgehog pathway

Hepatocellular carcinoma (HCC), commonly caused by liver fibrosis, is a global challenge with high morbidity. Activation of hepatic stellate cells (HSCs) contributes to hepatic fibrosis. Exosomes are small vesicles that play a significant role in cell-to-cell communication. Smoothened (SMO) is the key signal transducer for Hedgehog pathway. This study was designed to study the function and underlying mechanism of SMO in HSC activation. Functional assays including 5-Ethynyl-2´-deoxyuridine, colony formation, wound healing, transwell, and sphere formation assays disclosed the function of SMO. Western blot analysis of exosome biomarkers, immunofluorescence staining assay, electron microscope, and flow cytometry revealed the existence of exosomes. Bioinformatics analyses and mechanistic assays uncovered the interplays between RNAs. Nude mice xenograft model was established to evaluate HCC tumor growth. We uncovered that SMO was an oncogene in HCC cells and was low-expressed in quiescent HSCs. Then, SMO was upregulated in HSCs cultured with HCC cells-conditioned medium. Next, it was revealed that HCC cells-derived exosomes activated HSCs by transmitting SMO to HSCs. Subsequently, we recognized that microRNA let-7b host gene (MIRLET7BHG) served as the competing endogenous RNA against miR-330-5p to upregulate SMO. In turn, SMO induced hedgehog pathway to promote GLI family zinc finger 1 (Gli1), leading to transcriptional activation of MIRLET7BHG in activated HSCs. In summary, this study demonstrated that Gli1-induced MIRLET7BHG facilitated HCC by activating HSCs through exosomal SMO to stimulate hedgehog pathway, providing a new road for HCC treatment.

Engineered models of tumor metastasis with immune cell contributions

Most cancer deaths are due to tumor metastasis rather than the primary tumor. Metastasis is a highly complex and dynamic process that requires orchestration of signaling between the tumor, its local environment, distant tissue sites, and immune system. Animal models of cancer metastasis provide the necessary systemic environment but lack control over factors that regulate cancer progression and often do not recapitulate the properties of human cancers. Bioengineered "organs-on-a-chip" that incorporate the primary tumor, metastatic tissue targets, and microfluidic perfusion are now emerging as quantitative human models of tumor metastasis. The ability of these systems to model tumor metastasis in individualized, patient-specific settings makes them uniquely suitable for studies of cancer biology and developmental testing of new treatments. In this review, we focus on human multi-organ platforms that incorporate circulating and tissue-resident immune cells in studies of tumor metastasis.

Characteristics of pre-metastatic niche: the landscape of molecular and cellular pathways

Metastasis is a major contributor to cancer-associated deaths. It involves complex interactions between primary tumorigenic sites and future metastatic sites. Accumulation studies have revealed that tumour metastasis is not a disorderly spontaneous incident but the climax of a series of sequential and dynamic events including the development of a pre-metastatic niche (PMN) suitable for a subpopulation of tumour cells to colonize and develop into metastases. A deep understanding of the formation, characteristics and function of the PMN is required for developing new therapeutic strategies to treat tumour patients. It is rapidly becoming evident that therapies targeting PMN may be successful in averting tumour metastasis at an early stage. This review highlights the key components and main characteristics of the PMN and describes potential therapeutic strategies, providing a promising foundation for future studies.

The dynamic behavior of lipid droplets in the pre-metastatic niche

The pre-metastatic niche is a favorable microenvironment for the colonization of metastatic tumor cells in specific distant organs. Lipid droplets (LDs, also known as lipid bodies or adiposomes) have increasingly been recognized as lipid-rich, functionally dynamic organelles within tumor cells, immune cells, and other stromal cells that are linked to diverse biological functions and human diseases. Moreover, in recent years, several studies have described the indispensable role of LDs in the development of pre-metastatic niches. This review discusses current evidence related to the biogenesis, composition, and functions of LDs related to the following characteristics of the pre-metastatic niche: immunosuppression, inflammation, angiogenesis/vascular permeability, lymphangiogenesis, organotropism, reprogramming. We also address the function of LDs in mediating pre-metastatic niche formation. The potential of LDs as markers and targets for novel antimetastatic therapies will be discussed.

TGF-β signaling in liver metastasis

The presence of liver metastases drastically worsens the prognosis of cancer patients. The liver is the second most prevalent metastatic site in cancer patients, but systemic therapeutic opportunities that target liver metastases are still limited. To aid the discovery of novel treatment options for metastatic liver disease, we provide insight into the cellular and molecular steps required for liver colonization. For successful colonization in the liver, adaptation of tumor cells and surrounding stroma is essential. This includes the formation of a pre-metastatic niche, the creation of a fibrotic and immune suppressive environment, angiogenesis, and adaptation of tumor cells. We illustrate that transforming growth factor β (TGF-β) is a central cytokine in all these processes. At last, we devise that future research should focus on TGF-β inhibitory strategies, especially in combination with immunotherapy. This promising systemic treatment strategy has potential to eliminate distant metastases as the efficacy of immunotherapy will be enhanced.

Current perspectives on inhibitory SMAD7 in health and disease

Transforming growth factor β (TGF-β) family members play an extensive role in cellular communication that orchestrates both early development and adult tissue homeostasis. Aberrant TGF-β family signaling is associated with a pathological outcome in numerous diseases, and in-depth understanding of molecular and cellular processes could result in therapeutic benefit for patients. Canonical TGF-β signaling is mediated by receptor-regulated SMADs (R-SMADs), a single co-mediator SMAD (Co-SMAD), and inhibitory SMADs (I-SMADs). SMAD7, one of the I-SMADs, is an essential negative regulator of the pleiotropic TGF-β and bone morphogenetic protein (BMP) signaling pathways. In a negative feedback loop, SMAD7 inhibits TGF-β signaling by providing competition for TGF-β type-1 receptor (TβRI), blocking phosphorylation and activation of SMAD2. Moreover, SMAD7 recruits E3 ubiquitin SMURF ligases to the type I receptor to promote ubiquitin-mediated proteasomal degradation. In addition to its role in TGF-β and BMP signaling, SMAD7 is regulated by and implicated in a variety of other signaling pathways and functions as a mediator of crosstalk. This review is focused on SMAD7, its function in TGF-β and BMP signaling, and its role as a downstream integrator and crosstalk mediator. This crucial signaling molecule is tightly regulated by various mechanisms. We provide an overview of the ways by which SMAD7 is regulated, including noncoding RNAs (ncRNAs) and post-translational modifications (PTMs). Finally, we discuss its role in diseases, such as cancer, fibrosis, and inflammatory bowel disease (IBD).

Exosome-Derived LncRNAs in Lung Cancer

As extracellular vesicles, exosomes are released from most cells to perform cell–cell communication. Recent studies have shown that exosomes could be released into tumor microenvironment and blood to promote tumor progression through packaging and transmitting various bioactive molecules, such as cholesterol, proteins, lipids, miRNAs, mRNAs, and long non-coding RNAs (lncRNAs) to distant cells. LncRNAs have emerged as a major class of non-coding transcripts. A lot of LncRNAs have been discovered during the past few years of research on genomics. They have been proven to participate in various biological functions and disease processes through multiple mechanisms. In this review, we analyzed the role of exosome-derived lncRNAs in lung carcinogenesis and metastasis. We also highlight opportunities for the clinical potential of exosomes with specific lncRNAs as biomarkers and therapeutic intervention in lung cancer.

Inhibition Mir-92a Alleviates Oxidative Stress and Apoptosis of Alveolar Epithelial Cells Induced by Lipopolysaccharide Exposure through TLR2/AP-1 Pathway

OBJECTIVE

To probe into the role of miR-92a in alleviating oxidative stress and apoptosis of alveolar epithelial cell (AEC) injury induced by lipopolysaccharide (LPS) exposure through the Toll-like receptor (TLR) 2/activator protein-1 (AP-1) pathway.

METHODS

Acute lung injury (ALI) rat model and ALI alveolar epithelial cell model were constructed to inhibit the expression of miR-92a/TLR2/AP-1 in rat and alveolar epithelial cells (AECs), to detect the changes of oxidative stress, inflammatory response, and cell apoptosis in rat lung tissues and AECs, and to measure the changes of wet-dry weight (W/D) ratio in rat lung tissues.

RESULTS

Both inhibition of miR-92a expression and knockout of TLR2 and AP-1 gene could reduce LPS-induced rat ALI, alleviate pulmonary edema, inhibit oxidative stress and inflammatory response, and reduce apoptosis of lung tissue cells. In addition, the TLR2 and AP-1 levels in the lung tissues of ALI rats were noticed to be suppressed when inhibiting the expression of miR-92a, and the AP-1 level was also decreased after the knockout of TLR2 gene. Further, we verified this relationship in AECs and found that inhibition of miR-92a/TLR2/AP-1 also alleviated LPS-induced AEC injury, reduced cell apoptosis, and inhibited oxidative stress and inflammatory response. What is more, like that in rat lung tissue, the phenomenon also existed in AECs, that is, when the expression of miR-92a was inhibited, the expression of TLR2 and AP-1 was inhibited, and silencing TLR2 can reduce the expression level of AP-1.

CONCLUSION

MiR-92a/TLR2/AP-1 is highly expressed in ALI, and its inhibition can improve oxidative stress and inflammatory response and reduce apoptosis of AECs.

Critical steps to tumor metastasis: alterations of tumor microenvironment and extracellular matrix in the formation of pre-metastatic and metastatic niche

For decades, cancer metastasis has been a heated topic for its high mortality. Previous research has shown that pre-metastatic niche and metastatic niche are the 2 crucial steps in cancer metastasis, assisting cancerous cells' infiltration, survival, and colonization at target sites. More recent studies have unraveled details about the specific mechanisms related to the modification of pro-invasion environments. Here, we will review literatures on extracellular matrix (ECM) alterations, general cancer metastasis, organ specificity, pre-metastatic niche, metastatic niche, colony formation and impact on the course of metastasis. Respectively, the metastatic mechanisms like effect of hypoxia or inflammation on pre-metastatic niche construction, as well as the interaction between cancer cells and local milieu will be discussed. Based on the evidences of metastatic niches, we revisit and discussed the "Seed and Soil" hypothesis by Paget. This review will seek to provide insight into the mechanism of metastatic organ specificity which pre-metastatic niche and metastatic niche might suggest from an evolutionary aspect.

Comprehensive landscape of extracellular vesicle-derived RNAs in cancer initiation, progression, metastasis and cancer immunology

Extracellular vesicles (EVs), a class of heterogeneous membrane vesicles, are generally divided into exosomes and microvesicles on basis of their origination from the endosomal membrane or the plasma membrane, respectively. EV-mediated bidirectional communication among various cell types supports cancer cell growth and metastasis. EVs derived from different cell types and status have been shown to have distinct RNA profiles, comprising messenger RNAs and non-coding RNAs (ncRNAs). Recently, ncRNAs have attracted great interests in the field of EV-RNA research, and growing numbers of ncRNAs ranging from microRNAs to long ncRNAs have been investigated to reveal their specific functions and underlying mechanisms in the tumor microenvironment and premetastatic niches. Emerging evidence has indicated that EV-RNAs are essential functional cargoes in modulating hallmarks of cancers and in reciprocal crosstalk within tumor cells and between tumor and stromal cells over short and long distance, thereby regulating the initiation, development and progression of cancers. In this review, we discuss current findings regarding EV biogenesis, release and interaction with target cells as well as EV-RNA sorting, and highlight biological roles and molecular mechanisms of EV-ncRNAs in cancer biology.

Non-Small-Cell Lung Cancer Signaling Pathways, Metabolism, and PD-1/PD-L1 Antibodies

Treatment of advanced (metastatic) non-small-cell lung cancer (NSCLC) is currently mainly based on immunotherapy with antibodies against PD-1 or PD-L1, alone, or in combination with chemotherapy. In locally advanced NSCLC and in early resected stages, immunotherapy is also employed. Tumor PD-L1 expression by immunohistochemistry is considered the standard practice. Response rate is low, with median progression free survival very short in the vast majority of studies reported. Herein, numerous biological facets of NSCLC are described involving driver genetic lesions, mutations ad fusions, PD-L1 glycosylation, ferroptosis and metabolic rewiring in NSCLC and lung adenocarcinoma (LUAD). Novel concepts, such as immune-transmitters and the effect of neurotransmitters in immune evasion and tumor growth, the nascent relevance of necroptosis and pyroptosis, possible new biomarkers, such as gasdermin D and gasdermin E, the conundrum of K-Ras mutations in LUADs, with the growing recognition of liver kinase B1 (LKB1) and metabolic pathways, including others, are also commented. The review serves to charter diverse treatment solutions, depending on the main altered signaling pathways, in order to have effectual immunotherapy. Tumor PDCD1 gene (encoding PD-1) has been recently described, in equilibrium with tumor PD-L1 (encoded by PDCD1LG1). Such description explains tumor hyper-progression, which has been reported in several studies, and poises the fundamental criterion that IHC PD-L1 expression as a biomarker should be revisited.