Intracellular and extracellular microRNAs in breast cancer

Recent progress in Surface-Enhanced Raman Spectroscopy detection of biomarkers in liquid biopsy for breast cancer

Breast cancer is the most commonly diagnosed cancer in women globally and a leading cause of cancer-related mortality. However, current detection methods, such as X-rays, ultrasound, CT scans, MRI, and mammography, have their limitations. Recently, with the advancements in precision medicine and technologies like artificial intelligence, liquid biopsy, specifically utilizing Surface-Enhanced Raman Spectroscopy (SERS), has emerged as a promising approach to detect breast cancer. Liquid biopsy, as a minimally invasive technique, can provide a temporal reflection of breast cancer occurrence and progression, along with a spatial representation of overall tumor information. SERS has been extensively employed for biomarker detection, owing to its numerous advantages such as high sensitivity, minimal sample requirements, strong multi-detection ability, and controllable background interference. This paper presents a comprehensive review of the latest research on the application of SERS in the detection of breast cancer biomarkers, including exosomes, circulating tumor cells (CTCs), miRNA, proteins and others. The aim of this review is to provide valuable insights into the potential of SERS technology for early breast cancer diagnosis.

ER Negative Breast Cancer and miRNA: There Is More to Decipher Than What the Pathologist Can See!

Breast cancer (BC), the most prevalent cancer in women, is a heterogenous disease. Despite advancements in BC diagnosis, prognosis, and therapeutics, survival rates have drastically decreased in the metastatic setting. Therefore, BC still remains a medical challenge. The evolution of high-throughput technology has highlighted gaps in the classification system of BCs. Of particular interest is the notorious triple negative BC, which was recounted as being heterogenous itself and it overlaps with distinct subtypes, namely molecular apocrine (MA) and luminal androgen (LAR) BCs. These subtypes are, even today, still misdiagnosed and poorly treated. As such, researchers and clinicians have been looking for ways through which to refine BC classification in order to properly understand the initiation, development, progression, and the responses to the treatment of BCs. One tool is biomarkers and, specifically, microRNA (miRNA), which are highly reported as associated with BC carcinogenesis. In this review, the diverse roles of miRNA in estrogen receptor negative (ER-) and androgen receptor positive (AR+) BC are depicted. While highlighting their oncogenic and tumor suppressor functions in tumor progression, we will discuss their diagnostic, prognostic, and predictive biomarker potentials, as well as their drug sensitivity/resistance activity. The association of several miRNAs in the KEGG-reported pathways that are related to ER-BC carcinogenesis is presented. The identification and verification of accurate miRNA panels is a cornerstone for tackling BC classification setbacks, as is also the deciphering of the carcinogenesis regulators of ER - AR + BC.

The role of microRNA-21 (miR-21) in pathogenesis, diagnosis, and prognosis of gastrointestinal cancers: A review

MicroRNAs (miRNAs) are small non-coding RNAs regulating the expression of several target genes. miRNAs play a significant role in cancer biology, as they can downregulate their corresponding target genes by impeding the translation of mRNA (at the mRNA level) as well as degrading mRNAs by binding to the 3'-untranslated (UTR) regions (at the protein level). miRNAs may be employed as cancer biomarkers. Therefore, miRNAs are widely investigated for early detection of cancers which can lead to improved survival rates and quality of life. This is particularly important in the case of gastrointestinal cancers, where early detection of the disease could substantially impact patients' survival. MicroRNA-21 (miR-21 or miRNA-21) is one of the most frequently researched miRNAs, where it is involved in the pathophysiology of cancer and the downregulation of several tumor suppressor genes. In gastrointestinal cancers, miR-21 regulates phosphatase and tensin homolog (PTEN), programmed cell death 4 (PDCD4), mothers against decapentaplegic homolog 7 (SMAD7), phosphatidylinositol 3-kinase /protein kinase B (PI3K/AKT), matrix metalloproteinases (MMPs), β-catenin, tropomyosin 1, maspin, and ras homolog gene family member B (RHOB). In this review, we investigate the functions of miR-21 in pathogenesis and its applications as a diagnostic and prognostic cancer biomarker in four different gastrointestinal cancers, including colorectal cancer (CRC), pancreatic cancer (PC), gastric cancer (GC), and esophageal cancer (EC).

Potential roles of extracellular vesicles as a noninvasive tool for prenatal genetic diagnosis

The rate of infertility is increasing owing to genetic and environmental factors. Consequently, assisted reproductive technology has been introduced as an alternative. Bearing in mind the global trend toward the transfer of only one embryo, there is an increasing trend for assessing embryo quality before transfer through prenatal genetic diagnosis (PGD) tests. This ensures that the best-quality embryos are implanted into the uterus. In the in vitro fertilization cycle, PGD is not only used for diseases or quality checks before embryo freezing but also for evaluating unfortunate risks, such as aneuploidy, signs of early abortions, and preterm birth. However, traditional preimplantation genetic testing and screening approaches are invasive and harm the health of both the mother and embryo, raising the risk of miscarriage. In the last decade, embryonic extracellular vesicles (EVs) have been investigated and have emerged as a promising diagnostic tool. In this mini-review, we address the use of EVs as a noninvasive biomarker in PGD to test for biological hazards within the embryo without invading its cells. We summarize the state-of-the-art in the use of the embryo's EV content, genomic DNA, messenger RNA, and microRNA in the spent culture medium and their relationship with embryo quality, successful implantation, and pregnancy.

Combination of Small Extracellular Vesicle-Derived Annexin A2 Protein and mRNA as a Potential Predictive Biomarker for Chemotherapy Responsiveness in Aggressive Triple-Negative Breast Cancer

Small extracellular vesicles (sEVs), mainly exosomes, are nanovesicles that shed from the membrane as intraluminal vesicles of the multivesicular bodies, serve as vehicles that carry cargo influential in modulating the tumor microenvironment for the multi-step process of cancer metastasis. Annexin A2 (AnxA2), a calcium(Ca²⁺)-dependent phospholipid-binding protein, is among sEV cargoes. sEV-derived AnxA2 (sEV-AnxA2) protein is involved in the process of metastasis in triple-negative breast cancer (TNBC). The objective of the current study is to determine whether sEV-AnxA2 protein and/or mRNA could be a useful biomarkers to predict the responsiveness of chemotherapy in TNBC. Removal of Immunoglobulin G (IgG) from the serum as well as using the System Bioscience's ExoQuick Ultra kit resulted in efficient sEV isolation and detection of sEV-AnxA2 protein and mRNA compared to the ultracentrifugation method. The standardized method was applied to the twenty TNBC patient sera for sEV isolation. High levels of sEV-AnxA2 protein and/or mRNA were associated with stage 3 and above in TNBC. Four patients who responded to neoadjuvant chemotherapy had high expression of AnxA2 protein and/or mRNA in sEVs, while other four who did not respond to chemotherapy had low levels of AnxA2 protein and mRNA in sEVs. Our data suggest that the sEV-AnxA2 protein and mRNA could be a combined predictive biomarker for responsiveness to chemotherapy in aggressive TNBC.

Can Soluble Immune Checkpoint Molecules on Exosomes Mediate Inflammation?

Immune checkpoints (ICPs) are major co-signaling pathways that trigger effector functions in immune cells, with isoforms that are either membrane bound, engaging in direct cell to cell activation locally, or soluble, acting at distant sites by circulating freely or potentially via extracellular vesicles (EVs). Exosomes are small EVs secreted by a variety of cells carrying various proteins and nucleic acids. They are distributed extensively through biological fluids and have major impacts on infectious diseases, cancer, and neuroinflammation. Similarly, ICPs play key roles in a variety of disease conditions and have been extensively utilized as a prognostic tool for various cancers. Herein, we explored if the association between exosomes and ICPs could be a significant contributor of inflammation, particularly in the setting of cancer, neuroinflammation and viral infections, wherein the up regulation in both exosomal proteins and ICPs correlate with immunosuppressive effects. The detailed literature review of existing data highlights the significance and complexity of these two important pathways in mediating cancer and potentiating neuroinflammation via modulating overall immune response. Cells increasingly secret exosomes in response to intracellular signals from invading pathogens or cancerous transformations. These exosomes can carry a variety of cargo including proteins, nucleic acids, cytokines, and receptors/ligands that have functional consequences on recipient cells. Illustration generated using BioRender software.

Overview of non-coding RNAs in breast cancers

Breast cancer in women is the second most common cancer and the fifth leading cause of cancer death worldwide. Although earlier diagnosis and detection of breast cancer has resulted in lower mortality rates, further advances in prevention, detection, and treatment are needed to improve outcomes and survival for women with breast cancer as well as to offer a personalized therapeutic approach. It is now well-established that non-coding RNAs (ncRNAs) represent 98% of the transcriptome but in-depth knowledge about their involvement in the regulation of gene expression is lacking. A growing body of research indicates that ncRNAs are essential for tumorigenesis by regulating the expression of tumour-related genes. In this review, we focus on their implication in breast cancer genesis but also report the latest knowledge of their theragnostic and therapeutic role. We highlight the need for accurate quantification of circulating ncRNAs which is determinant to develop reliable biomarkers. Further studies are mandatory to finally enter the era of personalized medicine for women with breast cancer.

The role of miRNAs as a big master regulator of signaling pathways involved in lymphoblastic leukemia

MicroRNAs (miRNAs) belong to small noncoding RNAs, which have long attracted researchers' attention because of their potency in acting either as oncogenes or tumor-suppressors in cancers. acute lymphocytic leukemia (ALL) and chronic lymphocytic leukemia (CLL) are two known types of leukemia with high mortality rates in adults and children. On a molecular basis, various signaling pathways are active in both types, making researchers consider the potential role of miRNAs in activating or suppressing these pathways to further hinder cancer development. In this review, we summarized the potential miRNAs, especially circulating ones, involved in essential signaling pathways in the ALL and CLL patients which serve as biomarkers and valuable targets in the treatment fields.

Pioneer Role of Extracellular Vesicles as Modulators of Cancer Initiation in Progression, Drug Therapy, and Vaccine Prospects

Cancer is one of the leading diseases, causing deaths worldwide. Nearly 10 million deaths were reported in 2020 due to cancer alone. Several factors are involved in cancer progressions, such as lifestyle and genetic characteristics. According to a recent report, extracellular vesicles (EVs) are involved in cancer initiation, progression, and therapy failure. EVs can play a major role in intracellular communication, the maintenance of tissue homeostasis, and pathogenesis in several types of diseases. In a healthy person, EVs carry different cargoes, such as miRNA, lncRNA etc., to help other body functions. On the other hand, the same EV in a tumor microenvironment carries cargoes such as miRNA, lncRNA, etc., to initiate or help cancer progression at various stages. These stages may include the proliferation of cells and escape from apoptosis, angiogenesis, cell invasion, and metastasis, reprogramming energy metabolism, evasion of the immune response, and transfer of mutations. Tumor-derived EVs manipulate by altering normal functions of the body and affect the epigenetics of normal cells by limiting the genetic makeup through transferring mutations, histone modifications, etc. Tumor-derived EVs also pose therapy resistance through transferring drug efflux pumps and posing multiple drug resistances. Such EVs can also help as biomarkers for different cancer types and stages, which ultimately help with cancer diagnosis at early stages. In this review, we will shed light on EVs' role in performing normal functions of the body and their position in different hallmarks of cancer, in altering the genetics of a normal cell in a tumor microenvironment, and their role in therapy resistance, as well as the importance of EVs as diagnostic tools.

Integrated view of molecular diagnosis and prognosis of dengue viral infection: future prospect of exosomes biomarkers

Dengue viruses (DENVs) are the viruses responsible for dengue infection which affects lungs, liver, heart and also other organs of individuals. DENVs consist of the group of four serotypically diverse dengue viruses transmitted in tropical and sub-tropical countries of world. Aedes mosquito is the principal vector which spread the infection from infected person to healthy humans. DENVs can cause different syndromes depending on serotype of virus which range from undifferentiated mild fever to dengue hemorrhagic fever resulting in vascular leakage due to release of cytokine and Dengue shock syndrome with fluid loss and hypotensive shock, or other severe manifestations such as bleeding and organ failure. Increase in dengue cases in pediatric population is a major concern. Transmission of dengue depends on various factors like temperature, rainfall, and distribution of Aedes aegypti mosquitoes. The present review describes a comprehensive overview of dengue, pathophysiology, diagnosis, treatment with an emphasis on potential of exosomes as biomarkers for early prediction of dengue in pediatrics.

Exosomes as potential diagnosis and treatment for liver cancer

BACKGROUND

Liver cancer is the fourth most significant cause of cancer-related death. Lack of early diagnosis strategy and a scarcity of efficient therapy constitute the main reasons for its lethality. Exosomes, which contain various bioactive molecules, are characterized by high biocompatibility, low immunogenicity, and high transport efficiency. As a result, exosomes have become a research hotspot and present significant potential for cancer diagnosis biomarkers, biotherapeutics, therapy targets, drug carriers and therapeutic agents.

AIM

To explore the potential of exosomes in the diagnosis and treatment of liver cancer.

METHODS

We conducted a systematic literature search via PubMed and Web of Science. The following keywords were used: "exosomal biomarkers", "exosomal therapy", "exosomal therapy", and "liver cancer" or "HCC". The duplicate data were deleted by EndNote software. Literature search focused on full-texts and references of each article were carefully checked. One author (Xiao-Cui Wei) screened the literature that met the following inclusion criteria: (1) Detection of exosomes or their contents in clinical samples (body fluid or tissue); or (2) Exosomes served as drug carriers or therapeutic factors. Two authors (Xiao-Cui Wei and Li-Juan Liu) independently reviewed all retained literature and analyzed the information.

RESULTS

A total of 1295 studies were identified using the systematic literature search. Of these, 835 duplicate studies were removed. A further 402 irrelevant studies were excluded due to being irrelevant, including other diseases, review articles, the literature containing neither clinical samples nor animal experiments, exosome-independent studies, methods for detecting exosomes, or articles in Chinese. Finally, 58 published papers were retained and analyzed in the study. It showed a list of potential exosomal biomarkers that were upregulated in the blood samples of patients with liver cancer. Those downregulated in exosomes might serve as possible biotherapeutics. Some exosomes derived from cells in vitro were used for cytology or animal experiments to explore the mechanism of these exosome contents in disease. These contents might serve as potential targets for liver cancer. Additionally, we also discussed that exosomes serve as drug carriers or therapeutic factors.

CONCLUSION

Exosomes might serve as potential biomarkers or therapeutic biotargets in liver cancer and have the potential to act as drug carriers and self-treatment factors for liver cancer patients.

Methodologies to Isolate and Purify Clinical Grade Extracellular Vesicles for Medical Applications

The use of extracellular vesicles (EV) in nano drug delivery has been demonstrated in many previous studies. In this study, we discuss the sources of extracellular vesicles, including plant, salivary and urinary sources which are easily available but less sought after compared with blood and tissue. Extensive research in the past decade has established that the breadth of EV applications is wide. However, the efforts on standardizing the isolation and purification methods have not brought us to a point that can match the potential of extracellular vesicles for clinical use. The standardization can open doors for many researchers and clinicians alike to experiment with the proposed clinical uses with lesser concerns regarding untraceable side effects. It can make it easier to identify the mechanism of therapeutic benefits and to track the mechanism of any unforeseen effects observed.

MicroRNAs Role in Breast Cancer: Theranostic Application in Saudi Arabia

Breast cancer is an aggressive silent disease, representing 11.7% of the diagnosed cancer worldwide, and it is also a leading cause of death in Saudi Arabia. Consequently, microRNAs have emerged recently as potential biomarkers to diagnose and monitor such cases at the molecular level, which tends to be problematic during diagnosis. MicroRNAs are highly conserved non- coding oligonucleotide RNA. Over the last two decades, studies have determined the functional significance of these small RNAs and their impact on cellular development and the interaction between microRNAs and messenger RNAs, which affect numerous molecular pathways and physiological functions. Moreover, many disorders, including breast cancer, are associated with the dysregulation of microRNA. Sparingly, many microRNAs can suppress cancer cell proliferation, apoptosis, angiogenesis, invasion, metastasis, and vice versa. Remarkably, microRNAs can be harvested from patients’ biofluids to predict disease progression that considered a non-invasive method. Nevertheless, MicroRNAs are currently utilized as anti- cancer therapies combined with other drug therapies or even as a single agents’ treatment. Therefore, this review will focus on microRNAs’ role in breast cancer as an indicator of disease progression. In addition, this review summarizes the current knowledge of drug sensitivity and methods in detecting microRNA and their application to improve patient care and identifies the current gaps in this field.

Human microRNA similarity in breast cancer

MicroRNAs (miRNAs) play important roles in a variety of human diseases, including breast cancer. A number of miRNAs are up- and down-regulated in breast cancer. However, little is known about miRNA similarity and similarity network in breast cancer. Here, a collection of 272 breast cancer-associated miRNA precursors (pre-miRNAs) were utilized to calculate similarities of sequences, target genes, pathways and functions and construct a combined similarity network. Well-characterized miRNAs and their similarity network were highlighted. Interestingly, miRNA sequence-dependent similarity networks were not identified in spite of sequence–target gene association. Similarity networks with minimum and maximum number of miRNAs originate from pathway and mature sequence, respectively. The breast cancer-associated miRNAs were divided into seven functional classes (classes I–VII) followed by disease enrichment analysis and novel miRNA-based disease similarities were found. The finding would provide insight into miRNA similarity, similarity network and disease heterogeneity in breast cancer.

Exosomes in Alzheimer's Disease: From Being Pathological Players to Potential Diagnostics and Therapeutics

Exosomes (EXOs) were given attention as an extracellular vesicle (EV) with a pivotal pathophysiological role in the development of certain neurodegenerative disorders (NDD), such as Parkinson's and Alzheimer's disease (AD). EXOs have shown the potential to carry pathological and therapeutic cargo; thus, researchers have harnessed EXOs in drug delivery applications. EXOs have shown low immunogenicity as natural drug delivery vehicles, thus ensuring efficient drug delivery without causing significant adverse reactions. Recently, EXOs provided potential drug delivery opportunities in AD and promising future clinical applications with the diagnosis of NDD and were studied for their usefulness in disease detection and prediction prior to the emergence of symptoms. In the future, the microfluidics technique will play an essential role in isolating and detecting EXOs to diagnose AD before the development of advanced symptoms. This review is not reiterative literature but will discuss why EXOs have strong potential in treating AD and how they can be used as a tool to predict and diagnose this disorder.

Cervical cancer development, chemoresistance, and therapy: a snapshot of involvement of microRNA

Cervical cancer (CC) is one of the leading causes of death in women due to cancer and a major concern in the developing world. Persistent human papilloma virus (HPV) infection is the major causative agent for CC. Besides HPV infection, genetic and epigenetic factors including microRNA (miRNA) also contribute to the malignant transformation. Earlier studies have revealed that miRNAs participate in cell proliferation, invasion and metastasis, angiogenesis, and chemoresistance processes by binding and inversely regulating the target oncogenes or tumor suppressor genes. Based on functions and mechanistic insights, miRNAs have been identified as cellular modulators that have an enormous role in diagnosis, prognosis, and cancer therapy. Signatures of miRNA could be used as diagnostic markers which are necessary for early diagnosis and management of CC. The therapeutic potential of miRNAs has been shown in CC; however, more comprehensive clinical trials are required for the clinical translation of miRNA-based diagnostics and therapeutics. Understanding the molecular mechanism of miRNAs and their target genes has been useful to develop miRNA-based therapeutic strategies for CC and overcome chemoresistance. In this review, we summarize the role of miRNAs in the development, progression, and metastasis of CC as well as chemoresistance. Further, we discuss the diagnostic and therapeutic potential of miRNAs to overcome chemoresistance and treatment of CC.

Myocardial Infarction-Associated Extracellular Vesicle-Delivered miR-208b Affects the Growth of Human Umbilical Vein Endothelial Cells via Regulating CDKN1A

This study was aimed at investigating the effects of myocardial infarction- (MI-) associated extracellular vesicle- (EV-) delivered miR-208b on human umbilical vein endothelial cells (HUVECs). EVs were isolated and subsequently stained with PHK67. A dual-luciferase reporter gene assay was used to determine the target of miR-208b. Afterwards, HUVECs were transfected with either MI-associated EVs or miR-208b mimics, and cell viability, migration, and apoptosis were subsequently measured. Real-time quantitative polymerase chain reaction (RT-qPCR) was applied to determine the expressions of the tested genes. NanoSight, transmission electron microscopy, and western blotting showed that EVs were successfully isolated. Among the potential microRNA biomarkers for MI, miR-208b was chosen for subsequent experiments. We found that MI-associated EVs could be taken up by HUVECs and confirmed that CDKN1A was a direct target of miR-208b. Additionally, miR-208b mimics and MI-associated EVs significantly inhibited the viability and migration of HUVECs (P < 0.05) and promoted cell apoptosis, as well as reduced S phase and increased G2/M phase cell distribution. RT-qPCR revealed that both miR-208b mimics and MI-associated EVs upregulated the expressions of CDKN1A, FAK, Raf-1, MAPK1, and Bax but downregulated the expression of Bcl2 and reduced the Bcl2/Bax ratio. Our study concludes that MI-associated EVs delivered miR-208b to HUVECs, and EV-delivered miR-208b could affect the growth of HUVECs by regulating the miR-208b/CDKN1A pathway; thus, miR-208b can be therefore served as important therapeutic targets for MI treatment.

Lifetime Impact of Cow's Milk on Overactivation of mTORC1: From Fetal to Childhood Overgrowth, Acne, Diabetes, Cancers, and Neurodegeneration

The consumption of cow's milk is a part of the basic nutritional habits of Western industrialized countries. Recent epidemiological studies associate the intake of cow's milk with an increased risk of diseases, which are associated with overactivated mechanistic target of rapamycin complex 1 (mTORC1) signaling. This review presents current epidemiological and translational evidence linking milk consumption to the regulation of mTORC1, the master-switch for eukaryotic cell growth. Epidemiological studies confirm a correlation between cow's milk consumption and birthweight, body mass index, onset of menarche, linear growth during childhood, acne vulgaris, type 2 diabetes mellitus, prostate cancer, breast cancer, hepatocellular carcinoma, diffuse large B-cell lymphoma, neurodegenerative diseases, and all-cause mortality. Thus, long-term persistent consumption of cow's milk increases the risk of mTORC1-driven diseases of civilization. Milk is a highly conserved, lactation genome-controlled signaling system that functions as a maternal-neonatal relay for optimized species-specific activation of mTORC1, the nexus for regulation of eukaryotic cell growth, and control of autophagy. A deeper understanding of milk´s impact on mTORC1 signaling is of critical importance for the prevention of common diseases of civilization.

Multiple microRNAs as biomarkers for early breast cancer diagnosis

MicroRNA (miRNA or miR) is stably present in plasma. It has been reported that miRNA could be used for detecting cancer. Circulating miRNAs are being increasingly recognized as powerful biomarkers in a number of different pathologies, including in breast cancer. The aim of the current study was to establish and validate miRNA sets that are useful for the early diagnosis of breast cancer. Specifically, the current study intended to determine whether miRNA biomarkers were tumor-specific and to statistically verify whether circulating miRNA analysis could be used for breast cancer diagnosis. In the present study, a total of nine candidate miRNA biomarkers were selected by examining reference miRNAs associated with the generation and progression of breast cancer to identify novel miRNAs that could be used to detect early breast cancer. A total of 226 plasma samples from patients with breast cancer were used. In addition, 146 plasma healthy samples were used as non-cancer controls. These samples were divided into training and validation cohorts. The training cohort was used to identify a combination of miRNA that could detect breast cancer. The validation cohort was used to validate this combination of miRNA. Total RNAs were isolated from collected samples. A total of 9 miRNAs were quantified using reverse-transcription quantitative PCR. A total of nine candidate miRNA expression levels were compared between patients with breast cancer and healthy controls. It was indicated that combinations of two or more of the nine miRNAs could detect breast cancer with higher accuracy than the use of a single biomarker. As a representative example, combinations of four miRNAs (miR-1246+miR-206+miR-24+miR-373) of the nine miRNAs had a sensitivity of 98%, a specificity of 96% and an accuracy of 97% for breast cancer detection in the validation cohort. The results of the present study suggest that multiple miRNAs could be used as potential biomarkers for early diagnosis of breast cancer. These biomarkers are expected to overcome limitations of mammography when used as an auxiliary diagnosis of mammography.

MicroRNA-1297 downregulation inhibits breast cancer cell epithelial-mesenchymal transition and proliferation in a FA2H-dependent manner

Breast cancer (BC) is one of the most common malignant tumors among women worldwide. MicroRNAs (miRs) may be involved in several types of human cancer, including gastric, liver, lung and breast cancer. The aim of the present study was to investigate the effect of miR-1297 on MDA-MB-231 cell epithelial-mesenchymal transition (EMT) and proliferation, and the underlying molecular mechanisms. MDA-MB-231 cells were transfected with miR-1297 inhibitor or inhibitor control for 48 h. Subsequently, MTT and flow cytometry assays indicated that miR-1297 inhibitor significantly decreased cell proliferation and induced apoptosis compared with the inhibitor control group. In addition, reverse transcription-quantitative PCR and western blotting suggested that miR-1297 inhibitor suppressed EMT in MDA-MB-231 cells compared with the inhibitor control group. TargetScan bioinformatics analysis and a dual-luciferase reporter gene assay were performed, which predicted that miR-1297 directly targeted fatty acid 2-hydroxylase (FA2H). Furthermore, MDA-MB-231 cells were transfected with control-plasmid or FA2H-plasmid for 48 h. The results demonstrated that FA2H overexpression decreased MDA-MB-231 cell proliferation and increased apoptosis compared with the control-plasmid group. Additionally, FA2H-plasmid increased E-cadherin expression levels, and reduced N-cadherin and matrix metalloproteinase 9 expression levels at both the protein and mRNA level compared with control-plasmid. Finally, MDA-MB-231 cells were transfected with control-small interfering (si)RNA, FA2H-siRNA, inhibitor control, miR-1297 inhibitor, miR-1297 inhibitor + control siRNA or miR-1297 inhibitor + FA2H-siRNA, and the results suggested that the biological effects of miR-1297 inhibitor were reversed by co-transfection with FA2H siRNA. In conclusion, the present study indicated that miR-1297/FA2H might serve as a novel potential biomarker and therapeutic target for BC.

Measurement and standardization challenges for extracellular vesicle therapeutic delivery vectors

Extracellular vesicles (EVs), such as exosomes and microvesicles, are nonreplicating lipid bilayer particles shed by most cell types which have the potential to revolutionize the development and efficient delivery of clinical therapeutics. This article provides an introduction to the landscape of EV-based vectors under development for the delivery of protein- and nucleic acid-based therapeutics. We highlight some of the most pressing measurement and standardization challenges that limit the translation of EVs to the clinic. Current challenges limiting development of EVs for drug delivery are the lack of: standardized cell-based platforms for the production of EV-based therapeutics; EV reference materials that allow researchers/manufacturers to validate EV measurements and standardized measurement systems for determining the molecular composition of EVs.

Exosome: An Emerging Source of Biomarkers for Human Diseases

Exosomes are 30-120nm long endocytic membrane-derived vesicles, which are secreted by various types of cells and stably present in body fluids, such as plasma, urine, saliva and breast milk. Exosomes participate in intercellular communication. Recently accumulative studies have suggested that exosomes may serve as novel biomarkers for disease diagnosis and prognosis. Herein, we reviewed the biological features of exosomes, technologies for exosome isolation and identification, as well as progress in exosomal biomarker identification, highlighting the relevance of exosome to human diseases and significance and great potential in translational medicine.

Methods for the Determination of the Purity of Exosomes

BACKGROUND

Exosomes open exciting new opportunities for advanced drug transport and targeted release. Furthermore, exosomes may be used for vaccination, immunosuppression or wound healing. To fully utilize their potential as drug carriers or immune-modulatory agents, the optimal purity of exosome preparations is of crucial importance.

METHODS

Articles describing the isolation and purification of exosomes were retrieved from the PubMed database.

RESULTS

Exosomes are often separated from biological fluids containing high concentrations of proteins, lipids and other molecules that keep vesicle purification challenging. A great number of purification protocols have been published, however, their outcome is difficult to compare because the assessment of purity has not been standardized. In this review, we first give an overview of the generation and composition of exosomes, as well as their multifaceted biological functions that stimulated various medical applications. Finally, we describe various methods that have been used to purify small vesicles and to assess the purity of exosome preparations and critically compare the quality of these evaluation protocols.

CONCLUSION

Combinations of various techniques have to be applied to reach the required purity and quality control of exosome preparations.

MiR-519d-3p in Trophoblastic Cells: Effects, Targets and Transfer to Allogeneic Immune Cells via Extracellular Vesicles

Members of the placenta-specific miRNA cluster C19MC, including miR-519d, are secreted by fetal trophoblast cells within extracellular vesicles (EVs). Trophoblast-derived EVs can be internalized by the autologous trophoblast and surrounding maternal immune cells, resulting in coordination of cellular responses. The study of functions and targets of placental miRNAs in the donor and recipient cells may contribute to the understanding of the immune tolerance essential in pregnancy. Here, we report that miR-519d-3p levels correlate positively with cell proliferation and negatively with migration in trophoblastic cell lines. Inhibition of miR-519d-3p in JEG-3 cells increases caspase-3 activation and apoptosis. PDCD4 and PTEN are targeted by miR-519d-3p in a cell type-specific manner. Transfection of trophoblastic cell lines with miR-519d mimic results in secretion of EVs containing elevated levels of this miRNA (EV_miR-519d). Autologous cells enhance their proliferation and decrease their migration ability when treated with EV_miR-519d. NK92 cells incorporate EV-delivered miR-519d-3p at higher levels than Jurkat T cells. EV_miR-519d increases the proliferation of Jurkat T cells but decreases that of NK92 cells. Altogether, miR-519d-3p regulates pivotal trophoblast cell functions, can be transferred horizontally via EVs to maternal immune cells and exerts functions therein. Vesicular miRNA transfer from fetal trophoblasts to maternal immune cells may contribute to the immune tolerance in pregnancy.

Exosomal miRNAs in hepatitis B virus related liver disease: a new hope for biomarker

The World Health Organisation, in its 2019 progress report on HIV, viral hepatitis and STDs indicates that 257 million people are afflicted with chronic HBV infections, of which, 1 million patients lose their lives every year due to HBV related chronic liver diseases including serious complications such as liver cirrhosis and hepatocellular carcinoma. The course of HBV infection and associated liver injury depend on several host factors, genetic variability of the virus, and the host viral interplay. The challenge of medical science is the early diagnosis/identification of the potential for development of fatal complications like liver cirrhosis and HCC so that timely medical intervention can improve the chances of survival. Currently, neither the vaccination regime nor the diagnostic methods are completely effective as reflected in the high number of annual deaths. It is evident from numerous publications that microRNAs (miRNAs) are the critical regulators of gene expression and various cellular processes like proliferation, development, differentiation, apoptosis and tumorigenesis. Expressions of these diminutive RNAs are significantly affected in cancerous tissues as a result of numerous genomic and epigenetic modifications. Exosomes are membrane-derived vesicles (30–100 nm) secreted by normal as well as malignant cells, and are present in all body fluids. They are recognized as critical molecules in intercellular communication between cells through horizontal transfer of information via their cargo, which includes selective proteins, mRNAs and miRNAs. Exosomal miRNAs are transferred to recipient cells where they can regulate target gene expression. This provides an insight into the elementary biology of cancer progression and therefore the development of therapeutic approaches. This concise review outlines various on-going research on miRNA mediated regulation of HBV pathogenesis with special emphasis on association of exosomal miRNA in advanced stage liver disease like hepatocellular carcinoma. This review also discusses the possible use of exosomal miRNAs as biomarkers in the early detection of HCC and liver cirrhosis.

Predictive role of single nucleotide polymorphism (rs11614913) in the development of breast cancer in Pakistani population

Aim: miRNAs play an important role in breast cancer (BC). Variations in miRNAs influence their maturation, expression and consequently regulation of their target genes. Materials & methods: In this study, single nucleotide polymorphism rs11614913 was genotyped in BC patients (n = 300) and 230 controls by employing tetra primer amplification refractory mutation system PCR and Sanger sequencing (Macrogen Korea). Results: A significant difference was observed in the genotypes through co-dominant (χ².#x00A0;= 42.03; p < 0.0001), additive (odds ratio [OR] = 0.6441 [0.4887-0.8490, 95% confidence interval]; p < 0.0019), dominant (OR = 0.3996 [0.2809-0.5686], p < 0.0001) and recessive (OR = 0.2993 [0.1220-0.7347], p < 0.009) statistical models showed decreased risk association of C allele with BC. Conclusion: Females having CT genotype are at higher risk of BC as compared with those having CC genotype.

The Microrna-143/145 Cluster in Tumors: A Matter of Where and When

The establishment and spreading of cancer involve the acquirement of many biological functions including resistance to apoptosis, enhanced proliferation and the ability to invade the surrounding tissue, extravasate from the primary site, survive in circulating blood, and finally extravasate and colonize distant organs giving origin to metastatic lesions, the major cause of cancer deaths. Dramatic changes in the expression of protein coding genes due to altered transcription factors activity or to epigenetic modifications orchestrate these events, intertwining with a microRNA regulatory network that is often disrupted in cancer cells. microRNAs-143 and -145 represent puzzling players of this game, with apparently contradictory functions. They were at first classified as tumor suppressive due to their frequently reduced levels in tumors, correlating with cell survival, proliferation, and migration. More recently, pro-oncogenic roles of these microRNAs have been described, challenging their simplistic definition as merely tumor-suppressive. Here we review their known activities in tumors, whether oncogenic or onco-suppressive, and highlight how their expression and functions are strongly dependent on their complex regulation downstream and upstream of cytokines and growth factors, on the cell type of expression and on the specific tumor stage.

The Promising Role of miR-21 as a Cancer Biomarker and Its Importance in RNA-Based Therapeutics

MicroRNAs are small noncoding transcripts that posttranscriptionally regulate gene expression via base-pairing complementarity. Their role in cancer can be related to tumor suppression or oncogenic function. Moreover, they have been linked to processes recognized as hallmarks of cancer, such as apoptosis, invasion, metastasis, and proliferation. Particularly, one of the first oncomiRs found upregulated in a variety of cancers, such as gliomas, breast cancer, and colorectal cancer, was microRNA-21 (miR-21). Some of its target genes associated with cancer are PTEN (phosphatase and tensin homolog), PDCD4 (programmed cell death protein 4), RECK (reversion-inducing cysteine-rich protein with Kazal motifs), and STAT3 (signal transducer activator of transcription 3). As a result, miR-21 has been proposed as a plausible diagnostic and prognostic biomarker, as well as a therapeutic target for several types of cancer. Currently, research and clinical trials to inhibit miR-21 through anti-miR-21 oligonucleotides and ADM-21 are being conducted. As all of the evidence suggests, miR-21 is involved in carcinogenic processes; therefore, inhibiting it could have effects on more than one type of cancer. However, whether miR-21 can be used as a tissue-specific biomarker should be analyzed with caution. Consequently, the purpose of this review is to outline the available information and recent advances regarding miR-21 as a potential biomarker in the clinical setting and as a therapeutic target in cancer to highlight its importance in the era of precision medicine.

Acid-Triggered Charge-Convertible Graphene-Based All-in-One Nanocomplex for Enhanced Genetic Phototherapy of Triple-Negative Breast Cancer

Highly efficient and stimulus-responsive nanomedicines for cancer treatment are currently receiving tremendous attention. In this study, an acid-triggered charge-reversible graphene-based all-in-one nanocomplex is appropriately designed by surface modification with multilayer polymers and simultaneous co-transportation of photosensitizer indocyanine green (ICG) and oligonucleotide inhibitor of miR-21 (miR-21i) to achieve highly efficient genetic phototherapy in a controlled manner. The nanocomplex (denoted as GPCP/miR-21i/ICG) effectively protects miR-21i from degradation and exhibits excellent photothermal/photochemical reactive oxygen species (ROS) generation as well as fluorescence imaging ability. The cargoes ICG and miR-21i can significantly be released at acidic pH compared with normal physiological medium and escaped from endosomes/lysosomes due to the acid-triggered charge reversal effect. Typically, the released miR-21i downregulate the endogenous miR-21 and result in the upregulation of the target proteins PTEN and Bax, thus increasing the phototherapeutic efficiency of ICG. High in vivo anticancer efficiency against the MDA-MB-231 triple-negative breast cancer (TNBC) model is obtained due to the combination of genetic regulation of miR-21i and the photokilling effect of ICG. This work highlights the great potential of this smart nanocomplex as an attractive modality of gene-photo combined treatment of cancer, especially for intractable TNBC.

Differentially expressed microRNAs in exosomes of patients with breast cancer revealed by next‑generation sequencing

MicroRNAs (miRNAs/miRs) in exosomes play crucial roles in the onset, progression and metastasis of cancer by regulating the stability of target mRNAs or by inhibiting translation. In the present study, differentially expressed miRNAs were identified in exosomes of 27 breast cancer patients and 3 healthy controls using RNA sequencing. The differentially expressed microRNAs were selected by bioinformatic analysis. Subjects were followed up for 2 years and exosomal miRNA profiles were compared between patients with and without recurrence of breast cancer. A total of 30 complementary DNA libraries were constructed and sequenced and 1,835 miRNAs were detected. There were no significant differences in the expression of miRNAs between the basal-like, human epidermal growth factor receptor-2⁺, luminal A, luminal B and healthy control (HC) groups. A total of 54 differentially expressed miRNAs were identified in triple-negative breast cancer (TNBC) patients vs. HCs, including 20 upregulated and 34 downregulated miRNAs. The results of the reverse transcription-quantitative PCR were consistent with this. Receiver operating characteristic curve analyses indicated that miR-150-5p [area under the curve (AUC)=0.705, upregulated], miR-576-3p (AUC=0.691, upregulated), miR-4665-5p (AUC=0.681, upregulated) were able to distinguish breast cancer patients with recurrence from those without recurrence. In conclusion, the present results indicated differences in miRNA expression profiles between patients with TNBC and healthy controls. Certain exosomal miRNAs were indicated to have promising predictive value as biomarkers for distinguishing breast cancer with recurrence from non-recurrence, which may be utilized for preventive strategies.

The Regulatory Role of MicroRNAs in Breast Cancer

MicroRNAs (miRNAs) are small non-coding RNA molecules which function as critical post-transcriptional gene regulators of various biological functions. Generally, miRNAs negatively regulate gene expression by binding to their selective messenger RNAs (mRNAs), thereby leading to either mRNA degradation or translational repression, depending on the degree of complementarity with target mRNA sequences. Aberrant expression of these miRNAs has been linked etiologically with various human diseases including breast cancer. Different cellular pathways of breast cancer development such as cell proliferation, apoptotic response, metastasis, cancer recurrence and chemoresistance are regulated by either the oncogenic miRNA (oncomiR) or tumor suppressor miRNA (tsmiR). In this review, we highlight the current state of research into miRNA involved in breast cancer, with particular attention to articles published between the years 2000 to 2019, using detailed searches of the databases PubMed, Google Scholar, and Scopus. The post-transcriptional gene regulatory roles of various dysregulated miRNAs in breast cancer and their potential as therapeutic targets are also discussed.

Role of tumor-derived exosomes in bone metastasis

Tight coupling between bone resorption and formation is essential for bone remodeling. Disruption of this equilibrium can lead to skeletal disorders. Osseous metastatic disease is a severe consequence of tumor cell dissemination from numerous primary cancer sites, including the prostate, lungs and breasts. Metastatic disease is one of the most common causes of mortality in patients with cancer. Rapid advances in the therapeutic options for bone disease, including the use of bisphosphonates, have achieved effective clinical effects. However, the overall survival time of patients with bone metastatic has not significantly improved. Exosomes, which originate from tumor tissue and preferentially the bone, provide a reasonable way to understand the mechanism of neoplastic bone metastasis. Recently, several studies have indicated that tumor-derived exosomes are involved in cancer progression. However, the potential role that exosomes serve in the pathological communication between tumor and bone cells within the skeletal microenvironment remains an emerging field. The present review reports some recent findings on the detrimental roles of exosomes in bone metastasis. In addition, since exosomes are involved in metabolic organ cross-talk, this review highlights the involvement of cancer-derived exosomes in the regulation of skeletal metastatic diseases. Lastly, the potential promising clinical applications and emerging therapeutic opportunities targeting exosomes are discussed as novel strategies for cancer therapy.

Personalized medicine: From diagnostic to adaptive

Personalized therapy has made great strides but suffers from the lack of companion diagnostics. With the dawn of extracellular vesicle (EV) based liquid biopsies fast approaching, this article proposes a novel approach to cancer treatment – adaptive therapy. Already being implemented in the field of radiation oncology, adaptive radiation therapy utilizes cutting-edge imaging techniques as a viable means to monitor a patient's tumor throughout the entire treatment cycle by adapting the dosage and alignment to match the dynamic tumor. Through an EV liquid biopsy, medical oncologists will also soon have the means to continuously monitor a patient's tumor as it changes over time. With this information, physicians will be able to “adapt” pre-planned therapies concurrently with the fluctuating tumor environment, thus creating a more precise personalized medicine. In this article, a theory for adaptive medicine and the current state of the field with an outlook on future challenges are discussed.

Probing direct interaction of oncomiR-21-3p with the tumor suppressor p53 by fluorescence, FRET and atomic force spectroscopy

miRNA-21-3p is overexpressed in a number of cancers and contributes to their development with a concomitant inhibition of the p53 onco-suppressive function. While a direct interaction of p53 with some miRNA precursors (namely pri-miRNAs and pre-miRNAs) was found, no interaction with mature micro RNA has been so far evidenced. It could therefore be very interesting to investigate if a direct interaction of miR-21-3p and p53 is occurring with possible impairment of the p53 onco-suppressive function. Fluorescence and Atomic Force Spectroscopy (AFS) were applied to study the interaction of p53 DNA Binding Domain (DBD) and miRNA-21-3p. Förster resonance energy transfer (FRET) was used to measure the distance between the DBD lone tryptophan (FRET donor) and a dye (FRET acceptor) bound to miRNA-21-3p. AFS and Fluorescence evidenced a direct interaction between miRNA-21-3p and DBD; with the formed complex being characterized by an affinity of 10⁵ M, with a lifetime in the order of seconds. FRET allowed to determine an average distance of 4.0 nm between the DBD lone Trp146 and miRNA-21-3p; consistently with the involvement of the DBD L3 loop and/or the H1 helix in the complex formation, directly involved in the oligomerization and DNA binding. This may suggest that a functional inhibition of p53 could arise from its interaction with the oncogenic miRNA. Evidence of DBD-miRNA-21-3p complex formation may deserve some interest for inspiring novel therapeutic strategies.

Exosomes: The Indispensable Messenger in Tumor Pathogenesis and the Rising Star in Antitumor Applications

As natural secreted nanovesicles through the endolysosomal pathway, exosomes have attracted increasing attention over the past decades. An overwhelming number of studies have provided evidence for the intriguing roles that exosomes play in intercellular communication. They are widely involved in the transmission of biomolecule cargos between original cells and neighboring/distant cells in normal physiological processes. In addition, it has also been demonstrated that exosomes play vital roles in multiple biological pathways in the development of numerous diseases including cancer. Moreover, both natural and modified exosomes showed promising potential in serving as a versatile nanoplatform for cancer diagnosis and cancer therapy. This review aims to present a comprehensive and critical overview on the recent advances in exosome nanoscience and nanotechnology, ranging from their biogenesis, secretion, isolation, and biological function in tumor pathogenesis to their extensive antitumor applications.

Exosomes of pasteurized milk: potential pathogens of Western diseases

Milk consumption is a hallmark of western diet. According to common believes, milk consumption has beneficial effects for human health. Pasteurization of cow's milk protects thermolabile vitamins and other organic compounds including bioactive and bioavailable exosomes and extracellular vesicles in the range of 40-120 nm, which are pivotal mediators of cell communication via systemic transfer of specific micro-ribonucleic acids, mRNAs and regulatory proteins such as transforming growth factor-β. There is compelling evidence that human and bovine milk exosomes play a crucial role for adequate metabolic and immunological programming of the newborn infant at the beginning of extrauterine life. Milk exosomes assist in executing an anabolic, growth-promoting and immunological program confined to the postnatal period in all mammals. However, epidemiological and translational evidence presented in this review indicates that continuous exposure of humans to exosomes of pasteurized milk may confer a substantial risk for the development of chronic diseases of civilization including obesity, type 2 diabetes mellitus, osteoporosis, common cancers (prostate, breast, liver, B-cells) as well as Parkinson's disease. Exosomes of pasteurized milk may represent new pathogens that should not reach the human food chain.

Exosomes: fighting cancer with cancer

Exosomes are nanovesicles secreted by many cells, including cancer cells. Extensive research has been carried out to validate potential applications of exosomes and to evaluate their efficiency in a wide range of diseases, including cancer. The current knowledge on the origin, biogenesis and composition of exosomes is described. This review then focuses on the use of exosomes in cancer diagnostics and therapeutics.

Network pharmacology and RNA sequencing studies on triterpenoid saponins from Bupleurum chinense for the treatment of breast cancer

Breast cancer remains the most commonly diagnosed malignancy among women, which is frequently associated with adverse side-effects and high metastasis. Bupleurum chinense DC. has been empirically and extensively used as the core prescription for more than half of Chinese formulations for the adjuvant therapy of breast cancer, and its biological activity against breast cancer has been proven by both in vitro and in vivo experiments. Saikosaponin compounds are the characteristic constituent of B. chinense, which exhibit significant cytotoxicity toward several cancer cells. However, the specific mechanisms of these compounds in the treatment of breast cancer have not been comprehensively understood. Therefore, we aimed to determine more potentially therapeutic targets and investigate the biological mechanisms of B. chinense. In the present study, we adopted network pharmacology and bioinformatics analysis to facilitate this requirement. Consequently, the network analysis revealed that saikosaponin-f (39), saikosaponin-d (14), saikosaponin-c (26), saikosaponin-h (54), saikosaponin-g (41), 3′′,6′′-O-diacetylsaikosaponin-d (20), 11α-methoxy-saikosaponin-f (40), and 6′′-O-acetylsaikosaponin-b₁ (48) might play important roles in the treatment of breast cancer. In addition, the apoptosis regulator Bcl-2 (BCL-2), C-X-C chemokine receptor type 4 (CXCR4), probable ATP-dependent RNA helicase DDX5 (DDX5), protein kinase C alpha (PRKCA), and proto-oncogene tyrosine-protein kinase Src (SRC) were the potential therapeutic targets that exhibited intense interactions. Mechanistically, a gene enrichment analysis revealed that the action of B. chinense against breast cancer was achieved by the regulation of several biological signaling pathways, such as pathways in cancer, PI3K-Akt signaling pathway, EGFR tyrosine kinase inhibitor resistance, microRNAs in cancer, etc. More importantly, we verified that the predictions involving saikosaponin-d by the cytotoxicity assay, apoptosis analysis, and RNA sequencing methods were partly consistent with those obtained from the network pharmacology prediction.

The network pharmacology and RNA sequencing studies were used to explore potential therapeutic targets and biological mechanisms of B. chinense for the treatment of breast cancer.

Key microRNAs in the biology of breast cancer; emerging evidence in the last decade

microRNAs (miRNAs) are a family of small noncoding RNAs that play a pivotal role in the regulation of main biological and physiological processes, including cell cycle regulation, proliferation, differentiation, apoptosis, stem cell maintenance, and organ development. Dysregulation of these tiny molecules has been related to different human diseases, such as cancer. It has been estimated that more than 50% of these noncoding RNA sequences are placed on fragile sites or cancer-associated genomic regions. After the discovery of the first specific miRNA signatures in breast cancer, many studies focused on the involvement of these small RNAs in the pathophysiology of breast tumors and their possible clinical implications as reliable prognostic biomarkers or as a new therapeutic approach. Therefore, the present review will focus on the recent findings on the involvement of miRNAs in the biology of breast cancer associated with their clinical implications.

Serum exosomal hnRNPH1 mRNA as a novel marker for hepatocellular carcinoma

BACKGROUND

Distinctive exosomal contents could be useful for cancer diagnosis and prognosis. However, little is known about whether serum exosomal heterogeneous nuclear ribonucleoprotein H1 (hnRNPH1) mRNA is a satisfactory biomarker for hepatocellular carcinoma (HCC).

METHODS

Two hundred and ninety-one participants divided into four age- and gender-matched groups, including a HCC group (n=88), a liver cirrhosis (LC) group (n=67), a chronic hepatitis B (CHB) group (n=68) and a healthy control group (n=68), were enrolled. Serum exosomal hnRNPH1 mRNA and GAPDH mRNA were measured using TaqMan real-time PCR, and the relative expression levels were calculated. Receiver operating characteristic (ROC) curves were constructed to evaluate the effectiveness of hnRNPH1 mRNA alone and in combination with α-fetoprotein (AFP) in the diagnosis of HCC. The correlation between hnRNPH1 mRNA levels and clinicopathological characteristics and overall survival (OS) in HCC was determined.

RESULTS

The serum exosomal hnRNPH1 mRNA levels in HCC patients were remarkably higher than in the other groups (p<0.05). The hnRNPH1 mRNA discriminated HCC from CHB with an area under the ROC curve (AUC) of 0.865, with sensitivity of 85.2% and specificity of 76.5% at cut-off value of 0.670. The AUC for hnRNPH1 mRNA in combination with AFP was further improved. The exosomal hnRNPH1 mRNA levels in HCC patients were associated with the Child-Pugh classification, portal vein tumor emboli, lymph node metastasis, TNM stage and OS (p<0.05).

CONCLUSIONS

These findings suggested that serum exosomal hnRNPH1 mRNA could be an effective marker for HCC in high HBV prevalence areas.

Novel MicroRNA-Based Risk Score Identified by Integrated Analyses to Predict Metastasis and Poor Prognosis in Breast Cancer

BACKGROUND

The use of biomarkers that allow early therapeutic intervention or intensive follow-up evaluation is expected to be a powerful means for reducing breast cancer mortality. MicroRNAs (miRNAs) are known to play major roles in cancer biology including metastasis. This study aimed to develop a novel miRNA risk score to predict patient survival and metastasis in breast cancer.

METHODS

An integrated unbiased approach was applied to derive a composite risk score for prognosis based on miRNA expression in primary breast tumors in 1051 breast cancer patients from The Cancer Genome Atlas (TCGA). Further analysis of the risk score with metastasis/recurrence was performed using the TCGA data set and validated in a separate patient population using small RNA sequencing.

RESULTS

The three-miRNAs risk score (miR-19a, miR-93, and miR-106a) was developed using the TCGA cohort, which predicted poor prognosis (p = 0.0005) independently of known clinical risk factors. The prognostic value was validated in another three following independent cohorts: GSE19536 (p = 0.0009), GSE22220 (p = 0.0003), and the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) (p = 0.0023). The three-miRNAs risk score predicted bone recurrence in TCGA (p = 0.0052), and the findings were validated in another independent population of patients who experienced bone recurrence and age/stage-matched patients without any recurrence. The three-miRNAs risk score enriched multiple metastasis-related gene sets such as angiogenesis and epithelial mesenchymal transition in a gene-set-enrichment analysis.

CONCLUSIONS

The authors developed the novel miRNA-based risk score, which is a promising biomarker for prediction of worse survival and bone recurrence potential in breast cancer.

Nanoplasmonic pillars engineered for single exosome detection

Exosomes are secreted nanovesicles which incorporate proteins and nucleic acids, thereby enabling multifunctional pathways for intercellular communication. There is an increasing appreciation of the critical role they play in fundamental processes such as development, wound healing and disease progression, yet because of their heterogeneous molecular content and low concentrations in vivo, their detection and characterization remains a challenge. In this work we combine nano- and microfabrication techniques for the creation of nanosensing arrays tailored toward single exosome detection. Elliptically–shaped nanoplasmonic sensors are fabricated to accommodate at most one exosome and individually imaged in real time, enabling the label-free recording of digital responses in a highly multiplexed geometry. This approach results in a three orders of magnitude sensitivity improvement over previously reported real-time, multiplexed platforms. Each nanosensor is elevated atop a quartz nanopillar, minimizing unwanted nonspecific substrate binding contributions. The approach is validated with the detection of exosomes secreted by MCF7 breast adenocarcinoma cells. We demonstrate the increasingly digital and stochastic nature of the response as the number of subsampled nanosensors is reduced from four hundred to one.

MicroRNA-194 regulates cell viability and apoptosis by targeting CDH2 in prostatic cancer

Introduction

Prostate cancer (PCa) is one of the most common malignancies in men. However, a lack of understanding of the mechanism underlying PCa metastasis has strongly limited the effectiveness of therapy for this disease. Thus, investigating the mechanism of PCa may help improve the prognosis of PCa patients. The goal of this study was to investigate the role of microRNA-194 (miR-194) in PCa.

Materials and methods

The expression of miR-194 and cadherin 2 (CDH2) at the transcriptional level was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The MTT assay cell apoptosis assay and Western blotting were used to determine the role of miR-194 and CDH2 in the PC3 human PCa cell line. The dual luciferase reporter assay system was performed to clarify the relationship between miR-194 and CDH2. qRT-PCR results showed that miR-194 was downregulated and CDH2 was upregulated in PC3 cells.

Results

Transfection with miR-194 mimics decreased cell viability and increased the rate of apoptosis compared with the control group of PC3 cells. Bioinformatics and the luciferase reporter assay indicated that CDH2 was a target of miR-194, and Western blot analysis suggested that CDH2 was negatively regulated by miR-194. Further studies revealed that the downregulation of CDH2 suppressed cell viability and promoted the apoptosis of PC3 cells and that miR-194 directly targeted CDH2 in PC3 cells. Finally, the in vivo experiments showed that miR-194 mimics suppressed tumor growth and induced apoptosis in a greater proportion of cells by decreasing the expression of CDH2 compared with the control group.

Conclusion

The results of this study showed that miR-194 targeted CDH2 to regulate PCa cell survival in vitro and suppress tumor growth in vivo. These findings suggest that miR-194 may be a useful therapeutic target in PCa.

Tumor-derived exosomes in cancer metastasis risk diagnosis and metastasis therapy

Exosomes are endosomes secreted from the membrane by exocytosis as multivesicular bodies and are generally defined by their spherical, unilamellar morphology, size and the expression of specific biomarkers used for diagnosis or therapy targets. Recent research has reported a higher relationship between exosome enrichment and tumor disease development. In this review, we discuss exosome intercellular communication and functions in the pathology of disease, especially on the cancer metastasis related with exosome. We introduce how exosomes from cancer and stem cancer cells target different organs through transporting molecular proteins of exosome inclusions to improve or inhibit cancer metastasis as well as highlight exosome therapy strategies for tumor pathology involving microRNAs.

HIF-1α Promotes Breast Cancer Cell MCF-7 Proliferation and Invasion Through Regulating miR-210

OBJECTIVE

Many malignant tumors grow in hypoxic condition, which is associated with tumor growth, invasion, and metastasis. MicroRNAs are of great significance in the development of multiple malignant tumors. This study cultured breast cancer cell MCF-7 under the condition of different concentrations of oxygen, to test cell proliferation and invasion, and detect miR-210 expression, aiming to analyze the influence of hypoxia on breast cancer cell behaviors as well as miR-210 expressions.

MATERIALS AND METHODS

Breast cancer cell MCF-7 was cultured under normoxia, hypoxia, or anaerobic conditions for 12, 24, or 48 hours. Cell proliferation was detected by MTT assay. Cell invasion and migration were tested by transwell assay. HIF-1α mRNA and miR-210 expressions were determined by real-time polymerase chain reaction.

RESULTS

MCF-7 cell proliferation was gradually increased following time extension (p < 0.05). MCF-7 cell exhibited higher proliferation, invasion, and migration activities in hypoxic and anaerobic groups compared with those in normoxic group during the same time period. HIF-1α mRNA and miR-210 were significantly upregulated in anaerobic group compared with those in other groups (p < 0.05). HIF-1α mRNA and miR-210 were obviously elevated at 12, 24, and 48 hours (p < 0.05).

CONCLUSION

MCF-7 cell proliferation was increased, invasion and migration were enhanced, with upregulated expression of HIF-1α mRNA and miR-210 in the hypoxic and anaerobic group following time extension.

MicroRNA-223-3p regulates cell chemo-sensitivity by targeting FOXO3 in prostatic cancer

Prostate cancer (PCa) is one of the most common malignant cancers in male and docetaxel is commonly used as an effective chemotherapeutic drug for PCa patients. However, docetaxel resistance inhibits the therapeutic effect of this agent, thus investigating the mechanism of chemoresistance to docetaxel of PCa may help to improve the prognosis of PCa patients. In our present study, we found that miR-223-3p was up-regulated in PCa cell lines (C4-2, LNCap, PC3, DU-145). Transfection with miR-223-3p inhibitor increased chemo-sensitivity to docetaxel and cell apoptosis rate in PCa cells compared with docetaxel + miR-223-3p mock group, especially in DU-145 cells which were more resistant to docetaxel. Bioinformatics study and luciferase reporter assay indicated that FOXO3 was a target of miR-223-3p and the results from western blot suggested that FOXO3 was negatively regulated by miR-223-3p. Further study revealed that up-regulation of FOXO3 by transfection with pCMV-FOXO3 decreased the IC₅₀ values of docetaxel and increased cell apoptosis rate compared with docetaxel + pCMV-vector group, suggesting that overexpressed FOXO3 suppressed cell survival and sensitized PCa cells to docetaxel. Moreover, siRNA-mediated knockdown of FOXO3 abolished the effects of miR-223-3p inhibitor on chemo-sensitivity and apoptosis in PCa cells by increasing chemoresistance and decreasing cell apoptosis rate. Finally, the in vivo experiments showed that miR-223-3p inhibitor sensitized prostatic cancer mouse model to docetaxel by increasing the expression of FOXO3. In conclusion, our present study indicated that miR-223-3p regulated cell chemo-sensitivity by targeting FOXO3 in prostatic cancer both in vitro and in vivo, providing new potential therapeutic strategy for PCa treatment.

Tumor-promoting properties of miR-8084 in breast cancer through enhancing proliferation, suppressing apoptosis and inducing epithelial-mesenchymal transition

Background

Breast cancer is one of the most frequent malignancies and the second leading cause of cancer-related mortality in women. MicroRNAs play a key role in breast cancer development and progression. microRNA(miR)-8084 has been observed an aberrant expression in breast cancer. However, the functions and regulatory axes of miR-8084, particularly in breast cancer, were not entirely clear.

Methods

miR-8084 expression in breast cancer were investigated in a GEO dataset by in silico analysis and in 42 paired tumor tissues by qPCR. The effects of deregulation of miR-8084 on breast cancer cell proliferation, migration and invasion in vitro and tumorigenicity in vivo were examined by colony-formation assay, wound healing assay, transwell assay and nude mouse subcutaneous tumor formation model. The target gene of miR-8084 were predicted by TargetScan and miRDB, and confirmed by luciferase reporter system. The roles of miR-8084 in the breast cancer cell proliferation, apoptosis and epithelial–mesenchymal transition (EMT) were investigated by MTS, FACS and associated-marker detection by western blot.

Results

miR-8084 is significantly up-regulated in both serum and malignant tissues from the source of breast cancer patients. miR-8084 promotes the proliferation of breast cancer cells by activating ERK1/2 and AKT. Meanwhile miR-8084 inhibits apoptosis by decreasing p53-BAX related pathway. miR-8084 also enhances migration and invasion by inducing EMT. Moreover, the tumor suppressor ING2 is a potential target of miR-8084, and miR-8084 regulatory axes contribute to pro-tumor effect, at least partially through regulating ING2.

Conclusion

Our results strongly suggest that miR-8084 functions as an oncogene that promotes the development and progression of breast cancer, and miR-8084 is a potential new diagnostic marker and therapeutic target of breast cancer.