Exosomes Derived From MicroRNA-148b-3p-Overexpressing Human Umbilical Cord Mesenchymal Stem Cells Restrain Breast Cancer Progression

Human umbilical cord mesenchymal stem cells-derived exosomal microRNA-181a retards nasopharyngeal carcinoma development by mediating KDM5C

OBJECTIVE

It has been studied that mesenchymal stem cells (MSCs)-derived exosomes could suppress tumor growth in nasopharyngeal carcinoma (NPC) and microRNA-181a (miR-181a) could mediate drug resistance in NPC. Focused on this work, the mechanism of human umbilical cord MSCs (hUC-MSCs)-derived exosomal miR-181a was explored in NPC cell progression.

METHODS

NPC tissues and normal tissues were obtained from patients, and miR-181a and KDM5C expression was examined. hUC-MSCs-derived exosomes were extracted, identified and co-cultured with NPC cells (C666-1 and SUNE1). C666-1 cell progression in vitro and/or tumor growth in vivo were examined after incubation with exosomes, miR-181a or lysine-specific demethylase 5C (KDM5C). miR-181a and KDM5C expression were examined in NPC.

RESULTS

miR-181a expression was reduced while KDM5C expression was elevated in NPC. hUC-MSCs-derived exosomes restrained NPC cell growth in vivo and in vitro. Depleting or restoring exosomal miR-181a promoted or delayed NPC cell progression. KDM5C silencing suppressed NPC cell progression.

CONCLUSION

This study concluded that hUC-MSCs-derived exosomal miR-181a retards NPC development via negatively modulating KDM5C, serving as a candidate reference for the therapy of NPC.

Vascular endothelial cell-derived exosomal miR-30a-5p inhibits lung adenocarcinoma malignant progression by targeting CCNE2

This study tried to explore the molecular mechanism underlying progression of lung adenocarcinoma (LUAD), and discuss the extracellular communication between cancer cells and vascular endothelial cells. Roughly, differential analysis was carried out to note that miR-30a-5p was lowly expressed in LUAD while CCNE2 was highly expressed. Cell functional experiments demonstrated that overexpressed miR-30a-5p led to suppressed cell abilities in proliferation, migration and invasion. Dual-luciferase reporter gene assay and RNA immunoprecipitation verified the binding of miR-30a-5p and CCNE2, as well as decreased mRNA and protein expression of CCNE2 with miR-30a-5p overexpression. Simultaneous upregulation of miR-30a-5p and CCNE2 reversed the promotion of CCNE2 on malignant behaviors of LUAD cells. In vivo mice experiments exhibited that high miR-30a-5p expression hindered tumor growth. Additionally, miR-30a-5p was localized on the Extracellular Vesicles miRNA (EVmiRNA) database.MiR-30a-5p was abundant in exosomes derived from vascular endothelial cells. To validate that miR-30a-5p could be delivered to LUAD cells via exosomes and then make an effect, exosomes from vascular endothelial cells were firstly extracted and identified by transmission electron microscopy and detection of exosomal marker proteins (Alix, CD63, TSG101). Sequentially, the extracted exosomes were labeled with PKH67 to note that exosomes could be internalized by cancer cells. Further experiments indicated that miR-30a-5p was increased in cancer cells co-cultured with exosomes, which in turn suppressed cell malignant behaviors and made cell cycle arrest. In all, our findings clarified that exosomes derived from vascular endothelial cells delivered miR-30a-5p to LUAD cells to affect tumor malignant progression via the miR-30a-5p/CCNE2 axis.

Importance of the origin of mesenchymal (stem) stromal cells in cancer biology: "alliance" or "war" in intercellular signals

Mesenchymal stem cells (MSCs) play a central role in the intercellular signaling within the tumor microenvironment (TME), exchanging signals with cancer cells and tumor stromal cells, such as cancer-associated fibroblasts and inflammatory mononuclear cells. Research attributes both pro-tumor and anti-tumor actions to MSCs; however, evidence indicates that MSCs specific effect on the tumor depends on the source of the MSCs and the type of tumor. There are consistent data proving that MSCs from reproductive tissues, such as the uterus, umbilical cord or placenta, have potent anti-tumor effects and tropism towards tumor tissues. More interestingly, products derived from MSCs, such as secretome or extracellular vesicles, seem to reproduce the effects of their parental cells, showing a potential advantage for clinical treatments by avoiding the drawbacks associated with cell therapy. Given these perspectives, it appears necessary new research to optimize the production, safety and antitumor potency of the products derived from the MSCs suitable for oncological therapies.

MicroRNA-320a-containing exosomes from human umbilical cord mesenchymal stem cells curtail proliferation and metastasis in lung cancer by binding to SOX4

Exosomes from human umbilical cord mesenchymal stem cells (HUCMSCs) containing microRNAs (miRNAs) have been underscored as possible therapeutic options for cancers. Hence, our goal here was to investigate the relevance of miR-320a-containing exosomes from HUCMSCs to lung cancer. First, H1299 and H460 cells were co-cultured with the exosomes overexpressing miR-320a from HUCMSCs. The data displayed that HUCMSCs-secreted exosomes expressing miR-320a exerted anti-tumor effects in vitro and in vivo. Online analysis available at TargetScan database revealed that miR-320a bound to sex-determining region Y-box 4 (SOX4), and the luciferase reporter gene assay clarified this targeting relationship. Next, a β-catenin-specific agonist WAY-262611 was delivered into the H1299 and H460 cells to assess the effects of the Wnt/β-catenin pathway on lung cancer cellular processes. The results demonstrated that WAY-262611 potentiated lung cancer cell viability, invasion, and migration, but inhibited cell apoptosis. Altogether, exosomes carrying miR-320a from HUCMSCs might suppress lung cancer cell growth via the SOX4/Wnt/β-catenin axis, which highpoints the potency of exosomes expressing miR-320a as a possible therapeutic option for lung cancer treatment.

Biological Characteristics of Umbilical Cord Mesenchymal Stem Cells and Its Therapeutic Potential for Hematological Disorders

Umbilical cord mesenchymal stem cells (UC-MSCs) are a class of multifunctional stem cells isolated and cultured from umbilical cord. They possessed the characteristics of highly self-renewal, multi-directional differentiation potential and low immunogenicity. Its application in the field of tissue engineering and gene therapy has achieved a series of results. Recent studies have confirmed their characteristics of inhibiting tumor cell proliferation and migration to nest of cancer. The ability of UC-MSCs to support hematopoietic microenvironment and suppress immune system suggests that they can improve engraftment after hematopoietic stem cell transplantation, which shows great potential in treatment of hematologic diseases. This review will focus on the latest advances in biological characteristics and mechanism of UC-MSCs in treatment of hematological diseases.

Drug Resistance in Metastatic Breast Cancer: Tumor Targeted Nanomedicine to the Rescue

Breast cancer, specifically metastatic breast, is a leading cause of morbidity and mortality in women. This is mainly due to relapse and reoccurrence of tumor. The primary reason for cancer relapse is the development of multidrug resistance (MDR) hampering the treatment and prognosis. MDR can occur due to a multitude of molecular events, including increased expression of efflux transporters such as P-gp, BCRP, or MRP1; epithelial to mesenchymal transition; and resistance development in breast cancer stem cells. Excessive dose dumping in chemotherapy can cause intrinsic anti-cancer MDR to appear prior to chemotherapy and after the treatment. Hence, novel targeted nanomedicines encapsulating chemotherapeutics and gene therapy products may assist to overcome cancer drug resistance. Targeted nanomedicines offer innovative strategies to overcome the limitations of conventional chemotherapy while permitting enhanced selectivity to cancer cells. Targeted nanotheranostics permit targeted drug release, precise breast cancer diagnosis, and importantly, the ability to overcome MDR. The article discusses various nanomedicines designed to selectively target breast cancer, triple negative breast cancer, and breast cancer stem cells. In addition, the review discusses recent approaches, including combination nanoparticles (NPs), theranostic NPs, and stimuli sensitive or “smart” NPs. Recent innovations in microRNA NPs and personalized medicine NPs are also discussed. Future perspective research for complex targeted and multi-stage responsive nanomedicines for metastatic breast cancer is discussed.

The emerging role of miRNA in the perturbation of tumor immune microenvironment in chemoresistance: Therapeutic implications

Chemoresistance is a major hindrance in cancer chemotherapies, a leading cause of tumor recurrence and cancer-related deaths. Cancer cells develop numerous strategies to elude immune attacks and are regulated by immunological factors. Cancer cells can alter the expression of several immune modulators to upregulate the activities of immune checkpoint pathways. Targeting the immune checkpoint inhibitors is a part of the cancer immunotherapy altered during carcinogenesis. These immune modulators have the capability to reprogram the tumor microenvironment, thereby change the efficacy of chemotherapeutics. In general, the sensitivity of drugs is reduced in the immunosuppressive tumor microenvironment, resulting in chemoresistance and tumor relapse. The regulation of microRNAs (miRNAs) is well established in cancer initiation, progression, and therapy. Intriguingly, miRNA affects cancer immune surveillance and immune response by targeting immune checkpoint inhibitors in the tumor microenvironment. miRNAs alter the gene expression at the post-transcriptional level, which modulates both innate and adaptive immune systems. Alteration of tumor immune microenvironment influences drug sensitivity towards cancer cells. Besides, the expression profile of immune-modulatory miRNAs can be used as a potential biomarker to predict the response and clinical outcomes in cancer immunotherapy and chemotherapy. Recent evidences have revealed that cancer-derived immune-modulatory miRNAs might be promising targets to counteract cancer immune escape, thereby increasing drug efficacy. In this review, we have compiled the role of miRNAs in overcoming the chemoresistance by modulating tumor microenvironment and discussed their preclinical and clinical implications.

Exosomal microRNAs: Pleiotropic Impacts on Breast Cancer Metastasis and Their Clinical Perspectives

As a major threat factor for female health, breast cancer (BC) has garnered a lot of attention for its malignancy and diverse molecules participating in its carcinogenesis process. Among these complex carcinogenesis processes, cell proliferation, epithelial-to-mesenchymal transition (EMT), mesenchymal-to-epithelial transition (MET), and angiogenesis are the major causes for the occurrence of metastasis and chemoresistance which account for cancer malignancy. MicroRNAs packaged and secreted in exosomes are termed "exosomal microRNAs (miRNAs)". Nowadays, more researches have uncovered the roles of exosomal miRNAs played in BC metastasis. In this review, we recapitulated the dual actions of exosomal miRNAs exerted in the aggressiveness of BC by influencing migration, invasion, and distant metastasis. Next, we presented how exosomal miRNAs modify angiogenesis and stemness maintenance. Clinically, several exosomal miRNAs can govern the transformation between drug sensitivity and chemoresistance. Since the balance of the number and type of exosomal miRNAs is disturbed in pathological conditions, they are able to serve as instructive biomarkers for BC diagnosis and prognosis. More efforts are needed to connect the theoretical studies and clinical traits together. This review provides an outline of the pleiotropic impacts of exosomal miRNAs on BC metastasis and their clinical implications, paving the way for future personalized drugs.

The Emerging Role of Exosomes in Oral Squamous Cell Carcinoma

Oral cancer constitutes approximately 2% of all cancers, while the most common type, oral squamous cell carcinoma (OSCC) represents 90% of oral cancers. Although the treatment of OSCC has improved recently, it still has a high rate of local recurrence and poor prognosis, with a 5-year survival rate of only 50%. Advanced stage OSCC tends to metastasize to lymph nodes. Thus, exploring new therapeutic strategies for OSCC is therefore an urgent priority. Exosomes, the small membrane vesicles derived from endosomes, have been detected in a wide array of bodily fluids. Exosomes contain a diversity of proteins, mRNAs, and non-coding RNAs, including microRNAs, long non-coding RNAs, piRNAs, circular RNAs, tsRNAs, and ribosomal RNAs, which are delivered to neighboring cells or even transported to distant sites. Exosomes have been associated with the tumorigenesis of OSCC, promote the proliferation, colonization, and metastasis of OSCC by transferring their contents to the target cells. Furthermore, exosomes are involved in the regulation of the tumor microenvironment to transform conditions favoring cancer progression in vivo. In this review, we summarize the crucial role of exosomes in the tumorigenesis and progression of OSCC and discuss the potential clinical application of exosomes in OSCC treatment.

Exosomes as Drug Delivery Systems: Endogenous Nanovehicles for Treatment of Systemic Lupus Erythematosus

Exosomes, nanometer-sized lipid-bilayer-enclosed extracellular vesicles (EVs), have attracted increasing attention due to their inherent ability to shuttle proteins, lipids and genes between cells and their natural affinity to target cells. Their intrinsic features such as stability, biocompatibility, low immunogenicity and ability to overcome biological barriers, have prompted interest in using exosomes as drug delivery vehicles, especially for gene therapy. Evidence indicates that exosomes play roles in both immune stimulation and tolerance, regulating immune signaling and inflammation. To date, exosome-based nanocarriers delivering small molecule drugs have been developed to treat many prevalent autoimmune diseases. This review highlights the key features of exosomes as drug delivery vehicles, such as therapeutic cargo, use of targeting peptide, loading method and administration route with a broad focus. In addition, we outline the current state of evidence in the field of exosome-based drug delivery systems in systemic lupus erythematosus (SLE), evaluating exosomes derived from various cell types and engineered exosomes.

Exosomes from microRNA-126 overexpressing mesenchymal stem cells promote angiogenesis by targeting the PIK3R2-mediated PI3K/Akt signalling pathway

microRNA‐126 (miR‐126), an endothelial‐specific miRNA, is associated with vascular homeostasis and angiogenesis. However, the efficiency of miR‐126‐based treatment is partially compromised due to the low efficiency of miRNA delivery in vivo. Lately, exosomes have emerged as a natural tool for therapeutic molecule delivery. Herein, we investigated whether exosomes derived from bone marrow mesenchymal stem cells (BMMSCs) can be utilized to deliver miR‐126 to promote angiogenesis. Exosomes were isolated from BMMSCs overexpressed with miR‐126 (Exo‐miR‐126) by ultracentrifugation. In vitro study, Exo‐miR‐126 treatment promoted the proliferation, migration and angiogenesis of human umbilical vein endothelial cells (HUVECs). Furthermore, the gene/protein expression of angiogenesis‐related vascular endothelial growth factor (VEGF) and angiotensin‐1 (Ang‐1) were up‐regulated after incubation with Exo‐miR‐126. Additionally, the expression level of phosphoinositol‐3 kinase regulatory subunit 2 (PIK3R2) showed an inverse correlation with miR‐126 in HUVECs. Particularly, the Exo‐miR‐126 treatment contributed to enhanced angiogenesis of HUVECs by targeting PIK3R2 to activate the PI3K/Akt signalling pathway. Similarly, Exo‐miR‐126 administration profoundly increased the number of newly formed capillaries in wound sites and accelerated the wound healing in vivo. The results demonstrate that exosomes derived from BMMSCs combined with miR‐126 may be a promising strategy to promote angiogenesis.

Extracellular Vesicle-Based Nucleic Acid Delivery: Current Advances and Future Perspectives in Cancer Therapeutic Strategies

Extracellular vesicles (EVs) are sophisticated and sensitive messengers released by cells to communicate with and influence distant and neighboring cells via selective transfer of bioactive content, including protein lipids and nucleic acids. EVs have therefore attracted broad interest as new and refined potential therapeutic systems in many diseases, including cancer, due to their low immunogenicity, non-toxicity, and elevated bioavailability. They might serve as safe and effective vehicles for the transport of therapeutic molecules to specific tissues and cells. In this review, we focus on EVs as a vehicle for gene therapy in cancer. We describe recent developments in EV engineering to achieve efficient intracellular delivery of cancer therapeutics and avoid off-target effects, to provide an overview of the potential applications of EV-mediated gene therapy and the most promising biomedical advances.

Exosome vesicle as a nano-therapeutic carrier for breast cancer

Breast cancer (BC) is one of the most common lethal diseases found in women; in which shortcomings of currently used treatment procedures and efficiency to target disease contribute to the increment in mortality. Despite other factors, exosomes, a major class of EVs (extracellular vesicles) also play a regulatory role in normal physiological processes and have a major function in proliferation, metastases, and resistance in BC. Interestingly, despite their role in the progression of BC, exosomes also showed their importance as a drug carrier in the targeted drug delivery. The present review aims to shed light on the role of exosomes as a potential nano-therapeutic vehicle in the targeted drug delivery for BC. Information for this review was searched from PubMed and Google Scholar mostly during the year 2019-2020 by using appropriate keywords. The exosomes have been efficiently used in cancer therapeutics where these nano vehicles having specific markers help in efficient targeted delivery of therapeutics including proteins, nucleic acid, and anti-cancer drugs to BC cells. The properties of exosomes as an efficient delivery system can be explored in the future and holds the potential to be used in other forms of cancer as well.

Exosomal microRNA‑146a derived from mesenchymal stem cells increases the sensitivity of ovarian cancer cells to docetaxel and taxane via a LAMC2‑mediated PI3K/Akt axis

The carrier role of exosomes from human umbilical cord mesenchymal stem cells (hUCMSCs) containing microRNAs (miRNAs) has been implicated in gene and drug therapy. The aim of the present study was to investigate the role of exosomal microRNA-146a (miR-146a) from hUCMSCs in ovarian cancer (OC). Following the generation of docetaxel (DTX)-resistant SKOV3 cells and taxane-resistant A2780 cells, exosomes were isolated from hUCMSCs and added to the chemoresistant cells. Microarray analysis revealed that miR-146a expression was upregulated in DTX/SKOV3 cells among 15 ectopically expressed miRNAs. Analysis using the StarBase and miRSearch databases demonstrated that miR-146a targeted laminin γ2 (LAMC2), which was further verified using dual-luciferase reporter assays. Subsequently, miR-146a inhibitor or LAMC2 overexpression vectors were transfected into hUCMSCs or OC cells, respectively, and their effects on growth and chemoresistance in OC cells were assessed. The hUCMSC-derived exosomes reduced cell growth and chemoresistance in OC. Furthermore, hUCMSC-derived exosomes with miR-146a expression knocked down increased OC cell growth and chemoresistance, which was mediated by the PI3K/Akt signaling pathway via LAMC2.

Adult Stem Cell-Derived Extracellular Vesicles in Cancer Treatment: Opportunities and Challenges

Adult stem cells (SCs) participate in tissue repair and homeostasis regulation. The relative ease of SC handling and their therapeutic effect has made of these cell popular candidates for cellular therapy. However, several problems interfere with their clinical application in cancer treatment, like safety issues, unpredictable pro-tumour effects, and tissue entrapment. Therefore cell-free therapies that exhibit SC properties are being investigated. It is now well known that adult SCs exhibit their therapeutic effect via paracrine mechanisms. In addition to secretory proteins, SCs also release extracellular vesicles (EV) that deliver their contents to the target cells. Cancer treatment is one of the most promising applications of SC-EVs. Moreover, SC-EVs could be modified to improve targeted drug delivery. The aim of the review is to summarise current knowledge of adult SC-EV application in cancer treatment and to emphasise future opportunities and challenges in cancer treatment.

The Emerging Roles of Exosomes as EMT Regulators in Cancer

Epithelial–mesenchymal transition (EMT) causes epithelial cells to lose their polarity and adhesion property, and endows them with migratory and invasive properties to enable them to become mesenchymal stem cells. EMT occurs throughout embryonic development, during wound healing, and in various pathological processes, including tumor progression. Considerable research in the last few decades has revealed that EMT is invariably related to tumor aggressiveness and metastasis. Apart from the interactions between numerous intracellular signaling pathways known to regulate EMT, extracellular modulators in the tumor microenvironment also influence tumor cells to undergo EMT, with extracellular vesicles (EVs) receiving increasing attention as EMT inducers. EVs comprise exosomes and microvesicles that carry proteins, nucleic acids, lipids, and other small molecules to stimulate EMT in cells. Among EVs, exosomes have been investigated in many studies, and their role has been found to be significant with respect to regulating intercellular communications. In this review, we summarize recent studies on exosomes and their cargoes that induce cancer-associated EMT. Furthermore, we describe the possible applications of exosomes as promising therapeutic strategies.

Gene Therapy in Cancer Treatment: Why Go Nano?

The proposal of gene therapy to tackle cancer development has been instrumental for the development of novel approaches and strategies to fight this disease, but the efficacy of the proposed strategies has still fallen short of delivering the full potential of gene therapy in the clinic. Despite the plethora of gene modulation approaches, e.g., gene silencing, antisense therapy, RNA interference, gene and genome editing, finding a way to efficiently deliver these effectors to the desired cell and tissue has been a challenge. Nanomedicine has put forward several innovative platforms to overcome this obstacle. Most of these platforms rely on the application of nanoscale structures, with particular focus on nanoparticles. Herein, we review the current trends on the use of nanoparticles designed for cancer gene therapy, including inorganic, organic, or biological (e.g., exosomes) variants, in clinical development and their progress towards clinical applications.