miRNA-1246 in extracellular vesicles secreted from metastatic tumor induces drug resistance in tumor endothelial cells

Extracellular vesicles from highly invasive melanoma subpopulations increase the invasive capacity of less invasive melanoma cells through mir-1246-mediated inhibition of CCNG2

Invasive growth is a critical process in tumor progression, requiring the activation of various molecular processes in tumor cells at the invasive front. Intercellular communication between heterogeneous tumor cells enhances cellular activation and adaptation to specific microenvironments. One mechanism of intercellular communication is the delivery of miRNAs through tumor cell-derived extracellular vesicles (EVs). In this context we have observed that conditioned media from a highly invasive cell subpopulation (BLM-HI) enhances the invasive capacity of the parental cell line (BLM). Therefore, we hypothesized that this complex change of cellular behavior is influenced by EV-transported miRNAs. The treatment of BLM cells with EVs derived from BLM-HI cells resulted in a significantly enhanced invasive capacity, as observed in Matrigel-embedded spheroids and in 2D Boyden chamber assays, with a dose-dependent effect. Conversely, the invasive capacity of BLM cells was reduced when secretion of EVs was inhibited by a sphingomyelinase inhibitor. To investigate the molecular mechanisms behind this effect, we performed next-generation sequencing and identified an enrichment of miR-1246 in these EVs. In functional analyses we demonstrated that both the EV mediated delivery of miR-1246 as well as overexpression contributes to the enhanced invasiveness of BLM cells. We identified a binding site of miR-1246 in the 3'UTR of cyclin G2 (CCNG2) and demonstrated direct binding by a luciferase reporter assay.Increased expression of CCNG2 has been associated with cancer metastasis and poor patient outcomes in other malignancies. Our study demonstrates that intercellular communication contributes to the transfer of properties, such as increased invasive capacity, between heterogeneous melanoma cells via EV-transported miRNAs.

Role of Non-Coding RNAs in Diagnosis, Prediction and Prognosis of Multiple Myeloma

Multiple myeloma (MM) is the second most common hematologic malignancy in the world and accounts for 15% of primary hemocytopathies, with an ever-increasing number of new cases. It is asymptomatic in 30% of instances; hence, the determination of highly sensitive and specific markers is necessary to make a proper diagnosis. In the last 20 years, miRNAs, involved in regulating the expression of genes responsible for cell proliferation and differentiation, including tumor cells, have been identified as potential diagnostic and prognostic markers. The main aim of the following review was to outline the role of miRNAs in the diagnosis and prognosis of MM, considering their role in the pathogenesis of the disease and identifying their target genes and pathways. For this purpose, publications dating from 2013-2023 have been reviewed. Based on the available data, it is concluded that non-coding RNAs including miRNAs could be potential markers in MM. Furthermore, they may serve as therapeutic targets for certain drugs.

Oral bacterium Streptococcus mutans promotes tumor metastasis through thrombosis formation

Thrombosis is a well-known cardiovascular disease (CVD) complication that has caused death in many patients with cancer. Oral bacteria have been reported to contribute to systemic diseases, including CVDs, and tumor metastasis. However, whether oral bacteria-induced thrombosis induces tumor metastasis remains poorly understood. In this study, the cariogenic oral bacterium Streptococcus mutans was used to examine thrombosis in vitro and in vivo. Investigation of tumor metastasis to the lungs was undertaken by intravenous S. mutans implantation using a murine breast cancer metastasis model. The results indicated that platelet activation, aggregation, and coagulation were significantly altered in S. mutans-stimulated endothelial cells (ECs), with elevated neutrophil migration, thereby inducing thrombosis formation. Streptococcus mutans stimulation significantly enhances platelet and tumor cell adhesion to the inflamed ECs. Furthermore, S. mutans-induced pulmonary thrombosis promotes breast cancer cell metastasis to the lungs in vivo, which can be reduced by using aspirin, an antiplatelet drug. Our findings indicate that oral bacteria promote tumor metastasis through thrombosis formation. Oral health management is important to prevent CVDs, tumor metastasis, and their associated death.

Acquisition of drug resistance in endothelial cells by tumor-derived extracellular vesicles and cancer progression

Angiogenesis by endothelial cells (ECs) is essential for tumor growth. Angiogenesis inhibitors are used in combination with anticancer drugs in many tumor types, but tumors eventually become resistant. Previously, the underlying mechanism for developing drug resistance was considered to be a change in the characteristics of tumor cells whereas ECs were thought to be genetically stable and do not contribute to drug resistance. However, tumor endothelial cells (TECs) have been shown to differ from normal endothelial cells (NECs) in that they exhibit chromosomal abnormalities, angiogenic potential, and drug resistance. Extracellular vesicles (EVs) secreted by tumor cells have recently attracted attention as a factor involved in the acquisition of such abnormalities. Various cells communicate with each other through EVs, and it has been reported that tumor-derived EVs act on other tumor cells or stromal cells to develop drug resistance. Drug-resistant tumor cells confer drug resistance to recipient cells by transporting mRNAs encoding ATP-binding cassette subfamily B member 1 (ABCB1) and ATP-binding cassette subfamily C member 1 (ABCC1) as well as miRNAs involved in signaling such as Akt, drug efflux transporters, and P-glycoprotein modulators via EVs. However, there are limited reports on the acquisition of drug resistance in ECs by tumor-derived EVs. Since drug resistance of ECs may induce tumor metastasis and support tumor cell proliferation, the mechanism underlying the development of resistance should be elucidated to find therapeutic application. This review provides insight into the acquisition of drug resistance in ECs via tumor EVs in the tumor microenvironment.

Crosstalk between Endothelial Cells and Tumor Cells: A New Era in Prostate Cancer Progression

Prostate cancer stands as one of the most prevalent malignancies afflicting men worldwide. The tumor microenvironment plays a pivotal role in tumor progression, comprising various cell types including endothelial cells, tumor-associated fibroblasts, and macrophages. Recent accumulating evidence underscores the indispensable contribution of endothelial cells to prostate cancer development. Both endothelial cells and tumor cells release a multitude of factors that instigate angiogenesis, metastasis, and even drug resistance in prostate cancer. These factors serve as regulators within the tumor microenvironment and represent potential therapeutic targets for managing prostate cancer. In this review, we provide an overview of the crucial functions of endothelial cells in angiogenesis, metastasis, and drug resistance, and their prospective therapeutic applications in combating this disease.

Stromal cells in the tumor microenvironment: accomplices of tumor progression?

The tumor microenvironment (TME) is made up of cells and extracellular matrix (non-cellular component), and cellular components include cancer cells and non-malignant cells such as immune cells and stromal cells. These three types of cells establish complex signals in the body and further influence tumor genesis, development, metastasis and participate in resistance to anti-tumor therapy. It has attracted scholars to study immune cells in TME due to the significant efficacy of immune checkpoint inhibitors (ICI) and chimeric antigen receptor T (CAR-T) in solid tumors and hematologic tumors. After more than 10 years of efforts, the role of immune cells in TME and the strategy of treating tumors based on immune cells have developed rapidly. Moreover, ICI have been recommended by guidelines as first- or second-line treatment strategies in a variety of tumors. At the same time, stromal cells is another major class of cellular components in TME, which also play a very important role in tumor metabolism, growth, metastasis, immune evasion and treatment resistance. Stromal cells can be recruited from neighboring non-cancerous host stromal cells and can also be formed by transdifferentiation from stromal cells to stromal cells or from tumor cells to stromal cells. Moreover, they participate in tumor genesis, development and drug resistance by secreting various factors and exosomes, participating in tumor angiogenesis and tumor metabolism, regulating the immune response in TME and extracellular matrix. However, with the deepening understanding of stromal cells, people found that stromal cells not only have the effect of promoting tumor but also can inhibit tumor in some cases. In this review, we will introduce the origin of stromal cells in TME as well as the role and specific mechanism of stromal cells in tumorigenesis and tumor development and strategies for treatment of tumors based on stromal cells. We will focus on tumor-associated fibroblasts (CAFs), mesenchymal stem cells (MSCs), tumor-associated adipocytes (CAAs), tumor endothelial cells (TECs) and pericytes (PCs) in stromal cells.

Extracellular Vesicles and Cancer Multidrug Resistance: Undesirable Intercellular Messengers?

Cancer multidrug resistance (MDR) is one of the main mechanisms contributing to therapy failure and mortality. Overexpression of drug transporters of the ABC family (ATP-binding cassette) is a major cause of MDR. Extracellular vesicles (EVs) are nanoparticles released by most cells of the organism involved in cell-cell communication. Their cargo mainly comprises, proteins, nucleic acids, and lipids, which are transferred from a donor cell to a target cell and lead to phenotypical changes. In this article, we review the scientific evidence addressing the regulation of ABC transporters by EV-mediated cell-cell communication. MDR transfer from drug-resistant to drug-sensitive cells has been identified in several tumor entities. This was attributed, in some cases, to the direct shuttle of transporter molecules or its coding mRNA between cells. Also, EV-mediated transport of regulatory proteins (e.g., transcription factors) and noncoding RNAs have been indicated to induce MDR. Conversely, the transfer of a drug-sensitive phenotype via EVs has also been reported. Additionally, interactions between non-tumor cells and the tumor cells with an impact on MDR are presented. Finally, we highlight uninvestigated aspects and possible approaches to exploiting this knowledge toward the identification of druggable processes and molecules and, ultimately, the development of novel therapeutic strategies.

Extracellular RNA in melanoma: Advances, challenges, and opportunities

Melanoma, a malignant mass lesion that originates in melanocytes and has a high rate of malignancy, metastasis, and mortality, is defined by these characteristics. Malignant melanoma is a kind of highly malignant tumor that produces melanin and has a high mortality rate. Its incidence accounts for 1%-3% of all malignant tumors and shows an obvious upward trend. The discovery of biomolecules for the diagnosis and treatment of malignant melanoma has important application value. So far, the exact molecular mechanism of melanoma development relevant signal pathway still remains unclear. According to previous studies, extracellular RNAs (exRNAs) have been implicated in tumorigenesis and spread of melanoma. They can influence the proliferation, invasion and metastasis of melanoma by controlling the expression of target genes and can also influence tumor progression by participating in signal transduction mechanisms. Therefore, understanding the relationship between exRNA and malignant melanoma and targeting therapy is of positive significance for its prevention and treatment. In this review, we did an analysis of extracellular vesicles of melanoma which focused on the role of exRNAs (lncRNAs, miRNAs, and mRNAs) and identifies several potential therapeutic targets. In addition, we discuss the typical signaling pathways involved in exRNAs, advances in exRNA detection and how they affect the tumor immune microenvironment in melanoma.

Dual-drug codelivery nanosystems: An emerging approach for overcoming cancer multidrug resistance

Multidrug resistance (MDR) promotes tumor recurrence and metastasis and heavily reduces anticancer efficiency, which has become a primary reason for the failure of clinical chemotherapy. The mechanisms of MDR are so complex that conventional chemotherapy usually fails to achieve an ideal therapeutic effect and even accelerates the occurrence of MDR. In contrast, the combination of chemotherapy with dual-drug has significant advantages in tumor therapy. A novel dual-drug codelivery nanosystem, which combines dual-drug administration with nanotechnology, can overcome the application limitation of free drugs. Both the characteristics of nanoparticles and the synergistic effect of dual drugs contribute to circumventing various drug-resistant mechanisms in tumor cells. Therefore, developing dual-drug codelivery nanosystems with different multidrug-resistant mechanisms has an important reference value for reversing MDR and enhancing the clinical antitumor effect. In this review, the advantages, principles, and common codelivery nanocarriers in the application of dual-drug codelivery systems are summarized. The molecular mechanisms of MDR and the dual-drug codelivery nanosystems designed based on different mechanisms are mainly introduced. Meanwhile, the development prospects and challenges of codelivery nanosystems are also discussed, which provide guidelines to exploit optimized combined chemotherapy strategies in the future.

miR-1246 in tumor extracellular vesicles promotes metastasis via increased tumor cell adhesion and endothelial cell barrier destruction

Background

Tumor blood vessels play a key role in tumor metastasis. We have previously reported that tumor endothelial cells (TECs) exhibit abnormalities compared to normal endothelial cells. However, it is unclear how TECs acquire these abnormalities. Tumor cells secrete extracellular vesicles (EVs) to create a suitable environment for themselves. We have previously identified miR-1246 to be more abundant in high metastatic melanoma EVs than in low metastatic melanoma EVs. In the current study, we focused on miR-1246 as primarily responsible for acquiring abnormalities in TECs and examined whether the alteration of endothelial cell (EC) character by miR-1246 promotes cancer metastasis.

Methods

We analyzed the effect of miR-1246 in metastatic melanoma, A375SM-EVs, in vivo metastasis. The role of tumor EV-miR-1246 in the adhesion between ECs and tumor cells and the EC barrier was addressed. Changes in the expression of adhesion molecule and endothelial permeability were examined.

Results

Intravenous administration of A375SM-EVs induced tumor cell colonization in the lung resulting in lung metastasis. In contrast, miR-1246 knockdown in A375SM decreased lung metastasis in vivo. miR-1246 transfection in ECs increased the expression of adhesion molecule ICAM-1 via activation of STAT3, followed by increased tumor cell adhesion to ECs. Furthermore, the expression of VE-Cadherin was downregulated in miR-1246 overexpressed EC. A375SM-EV treatment enhanced endothelial permeability. VE-Cadherin was validated as the potential target gene of miR-1246 via the target gene prediction database and 3' UTR assay.

Conclusion

miR-1246 in high metastatic tumor EVs promotes lung metastasis by inducing the adhesion of tumor cells to ECs and destroying the EC barrier.

In silico and in vitro analysis of the impact of single substitutions within EXO-motifs on Hsa-MiR-1246 intercellular transfer in breast cancer cell

MiR-1246 has recently gained much attention and many studies have shown its oncogenic role in colorectal, breast, lung, and ovarian cancers. However, miR-1246 processing, stability, and mechanisms directing miR-1246 into neighbor cells remain still unclear. In this study, we aimed to determine the role of single-nucleotide substitutions within short exosome sorting motifs - so-called EXO-motifs: GGAG and GCAG present in miR-1246 sequence on its intracellular stability and extracellular transfer. We applied in silico methods such as 2D and 3D structure analysis and modeling of protein interactions. We also performed in vitro validation through the transfection of fluorescently labeled miRNA to MDA-MB-231 cells, which we analyzed by flow cytometry and fluorescent microscopy. Our results suggest that nucleotides alterations that disturbed miR-1246 EXO-motifs were able to modulate miRNA-1246 stability and its transfer level to the neighboring cells, suggesting that the molecular mechanism of RNA stability and intercellular transfer can be closely related.

Role of miRNA in Melanoma Development and Progression

Melanoma is one of the most aggressive and progressive skin cancers. It develops from normal pigment-producing cells known as melanocytes, so it is important to know the mechanism behind such transformations. The study of metastasis mechanisms is crucial for a better understanding the biology of neoplastic cells. Metastasis of melanoma, or any type of cancer, is a multi-stage process in which the neoplastic cells leave the primary tumour, travel through the blood and/or lymphatic vessels, settle in distant organs and create secondary tumours. MicroRNA (miRNA) can participate in several steps of the metastatic process. This review presents the role of miRNA molecules in the development and progression as well as the immune response to melanoma.

The diagnostic and prognostic values of circulating miRNA-1246 in multiple myeloma

BACKGROUND/OBJECTIVE

Bone marrow biopsy, the gold standard for the diagnosis of multiple myeloma (MM), has main limitation of the invasiveness. Here, we explored the diagnostic and prognostic values of circulating miR-1246 in patients with MM.

MATERIAL AND METHODS

Ninety MM patients and 30 healthy donors (control group) were recruited in this study. The expression of miR-1246 in the peripheral blood samples was detected using qPCR. The receiver operating characteristic (ROC) curve was used to assess the diagnostic value of miR-1246 in MM. The Kaplan-Meier survival analyze was performed to evaluate the prognostic value of miR-1246.

RESULTS

The expression level of serum miR-1246 from newly diagnosed MM patients was significantly higher than that of the control group. Circulating miR-1246 level was decreased after treatment in remission patients, but remained high levels in relapsed patients (P < 0.05). ROC analysis demonstrated that miR-1246 showed a high diagnostic value in MM with an area under the curve (AUC) of 0.952, the sensitivity of 87%, and the specificity of 95% [95% confidence interval (CI) 0.902-1.007; P < 0.001]. Kaplan-Meier analysis showed that the progression-free survival (PFS) (14.0 months vs. 26.5 months, P = 0.045) and overall survival (OS) (20.5 months vs. 55.5 months, P = 0.014) were significantly shorter in patients with high miR-1246 expression as compared with those in patients with miR-1246 low expression. Multiple Cox regression model analysis showed that circulating miR-1246 was an independent prognostic factor for PFS (HR 2.786, 95% CI: 1.420-5.467, P = 0.003) and OS (HR 2.995, 95% CI: 1.166-7.689, P = 0.023) in MM patients.

CONCLUSION

This study demonstrates that circulating miR-1246 level is elevated in MM patients, which shows high values in the diagnosis and prognosis prediction in patients with MM.

Non-small cell lung cancer-derived exosomes promote proliferation, phagocytosis, and secretion of microglia via exosomal microRNA in the metastatic microenvironment

Non-small cell lung cancer (NSCLC) is the most common tumor that metastasizes to the brain. It is now accepted that the successful colonization and growth of tumor cells are determined by the interaction between tumor cells and the tumor microenvironment (TME). Microglia, brain innate immune cells, have been reported to play a vital role in the establishment of brain metastases. As essential mediators of intercellular communications, tumor-derived exosomes have an important role in the pathogenesis and progression of cancer by transferring their cargos to specific recipient cells. The crosstalk between microglia and tumor-derived exosomes has been extensively described. However, it is still unclear whether metastatic NSCLC cells secret exosomes to microglia and regulate the microglial functions. Here, our results showed that microglia aggregated in the brain metastatic sites. Meanwhile, microglia could take up the exosomes derived from NSCLC cells, leading to alterations of microglial morphology and increased proliferation, phagocytosis, and release of inflammatory cytokines including interleukin-6, interleukin-8, and CXCL1. Further investigation indicated that miR1246 was the most enriched microRNA in NSCLC-derived exosomes and mediated the partial effects of exosomes on microglia. Notably, miR1246 was also upregulated in the plasmatic exosomes of NSCLC patients. These results offer a new insight into the impact of NSCLC-derived exosomes on microglia and provide a new potential biomarker for diagnosing NSCLC.

Neutrophil Extracellular Vesicles: A Delicate Balance between Pro-Inflammatory Responses and Anti-Inflammatory Therapies

Extracellular vesicles (EVs) are released in the extracellular environment during cell activation or apoptosis. Working as signal transducers, EVs are important mediators of intercellular communication through the convoying of proteins, nucleic acids, lipids, and metabolites. Neutrophil extracellular vesicles (nEVs) contain molecules acting as key modulators of inflammation and immune responses. Due to their potential as therapeutic tools, studies about nEVs have been increasing in recent years. However, our knowledge about nEVs is still in its infancy. In this review, we summarize the current understanding of the role of nEVs in the framework of neutrophil inflammation functions and disease development. The therapeutic potential of nEVs as clinical treatment strategies is deeply discussed. Moreover, the promising research landscape of nEVs in the near future is also examined.

The oral bacterium Streptococcus mutans promotes tumor metastasis by inducing vascular inflammation

Recent studies have demonstrated a relationship between oral bacteria and systemic inflammation. Endothelial cells (ECs), which line blood vessels, control the opening and closing of the vascular barrier and contribute to hematogenous metastasis; however, the role of oral bacteria-induced vascular inflammation in tumor metastasis remains unclear. In this study, we examined the phenotypic changes in vascular ECs following Streptococcus mutans (S. mutans) stimulation in vitro and in vivo. The expression of molecules associated with vascular inflammation and barrier-associated adhesion was analyzed. Tumor metastasis was evaluated after intravenous injection of S. mutans in murine breast cancer hematogenous metastasis model. The results indicated that S. mutans invaded the ECs accompanied by inflammation and NF-κB activation. S. mutans exposure potentially disrupts endothelial integrity by decreasing VE-cadherin expression. The migration and adhesion of tumor cells were enhanced in S. mutans-stimulated ECs. Furthermore, S. mutans-induced lung vascular inflammation promoted breast cancer cell metastasis to the lungs in vivo. The results indicate that oral bacteria promote tumor metastasis through vascular inflammation and disruption of vascular barrier function. Improving oral hygiene in patients with cancer is of great significance in preventing postoperative pneumonia and tumor metastasis.

Circulating miR-1246 and miR-485-3p as Promising Biomarkers of Clinical Response and Outcome in Melanoma Patients Treated with Targeted Therapy

Despite the significant improvements in advanced melanoma therapy, there is still a pressing need for biomarkers that can predict patient response and prognosis, and therefore support rational treatment decisions. Here, we investigated whether circulating miRNAs could be biomarkers of clinical outcomes in patients treated with targeted therapy. Using next-generation sequencing, we profiled plasma miRNAs at baseline and at progression in patients treated with BRAF inhibitors (BRAFi) or BRAFi + MEKi. Selected miRNAs associated with response to therapy were subjected to validation by real-time quantitative RT-PCR . Receiver Operating Characteristics (ROC), Kaplan–Meier and univariate and multivariate Cox regression analyses were performed on the validated miR-1246 and miR-485-3p baseline levels. The median baseline levels of miR-1246 and miR-485-3p were significantly higher and lower, respectively, in the group of patients not responding to therapy (NRs) as compared with the group of responding patients (Rs). In Rs, a trend toward an increase in miR-1246 and a decrease in miR-485-3p was observed at progression. Baseline miR-1246 level and the miR-1246/miR-485-3p ratio showed a good ability to discriminate between Rs and NRs. Poorer PFS and OS were observed in patients with unfavorable levels of at least one miRNA. In multivariate analysis, a low level of miR-485-3p and a high miR-1246/miR-485-3p ratio remained independent negative prognostic factors for PFS, while a high miR-1246/miR-485-3p ratio was associated with an increased risk of mortality, although statistical significance was not reached. Evaluation of miR-1246 and miR-485-3p baseline plasma levels might help clinicians to identify melanoma patients most likely to be unresponsive to targeted therapy or at higher risk for short-term PFS and mortality, thus improving their management.

Exosomal microRNAs synergistically trigger stromal fibroblasts in breast cancer

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype. TNBC progression is sustained by recruitment of a strong tumor microenvironment (TME) mainly composed of cancer-associated fibroblasts (CAFs) able to endorse tumor hallmarks. Increasing evidences demonstrate that exosomes mediate the crosstalk between cancer cells and the TME. We examined TNBC-derived exosomes and their microRNA (miRNA) cargo in activation of normal fibroblasts (NFs) toward CAFs. We demonstrated that TNBC cell-derived exosomes increased NF collagen contraction and migration alongside CAF molecular markers. Exosome-activated fibroblasts promoted the invasion potential of normal breast epithelial cells, as assessed by an organotypic co-culture assay that resembled the in vivo context. We also investigated TNBC cell-derived exosome cargo in activating NFs to CAFs by performing small RNA sequencing. We found that the synergistic action of miR-185-5p, miR-652-5p, and miR-1246 boosted fibroblast migration and contraction, promoting specific CAF subspecialization toward a pro-migratory functional state. These data highlight the role of breast cancer cells in re-education of the TME and their contribution to tumor evolution.

The oxidized-LDL/LOX-1 axis in tumor endothelial cells enhances metastasis by recruiting neutrophils and cancer cells

Epidemiological relationships between cancer and cardiovascular diseases have been reported, but a molecular basis remains unclear. Some proteoglycans that strongly bind low-density-lipoprotein (LDL) are abundant both in atherosclerotic regions and in high metastatic-tumor tissue. LDL retention is crucial for the initiation of atherosclerosis, although its contribution to malignancy of cancer is not known. In this study, we show the importance of the accumulation of LDL in tumor metastasis. We demonstrated that high metastatic-tumor tissue contains high amounts of LDL and forms more oxidized LDL (ox-LDL). Interestingly, lectin-like ox-LDL receptor 1 (LOX-1), a receptor for ox-LDL and a recognized key molecule for cardiovascular diseases, was highly expressed in tumor endothelial cells (TECs). Neutrophils are important for ox-LDL formation. Since we observed the accumulation and activation of neutrophils in HM-tumors, we evaluated the involvement of LOX-1 in neutrophil migration and activation. LOX-1 induced neutrophil migration via CCL2 secretion from TECs, which was enhanced by ox-LDL. Finally, we show genetic manipulation of LOX-1 expression in TECs or tumor stroma tended to reduce lung metastasis. Thus, the LOX-1/ox-LDL axis in TECs may lead to the formation of a high metastatic-tumor microenvironment via attracting neutrophils. This article is protected by copyright. All rights reserved.

Identification of Two Exosomal miRNAs in Circulating Blood of Cancer Patients by Using Integrative Transcriptome and Network Analysis

Exosomes carry molecules of great biological and clinical interest, such as miRNAs. The contents of exosomes vary between healthy controls and cancer patients. Therefore, miRNAs and other molecules transported in exosomes are considered a potential source of diagnostic and prognostic biomarkers in cancer. Many miRNAs have been detected in recent years. Consequently, a substantial amount of miRNA-related data comparing patients and healthy individuals is available, which contributes to a better understanding of the initiation, development, malignancy, and metastasis of cancer using non-invasive sampling procedures. However, a re-analysis of available ncRNA data is rare. This study used available data about miRNAs in exosomes comparing healthy individuals and cancer patients to identify possible global changes related to the presence of cancer. A robust transcriptomic analysis identified two common miRNAs (miR-495-3p and miR-543) deregulated in five cancer datasets. They had already been implicated in different cancers but not reported in exosomes circulating in blood. The study also examined their target genes and the implications of these genes for functional processes.

A Review on the Role of miR-1246 in the Pathoetiology of Different Cancers

miR-1246 is a microRNA firstly recognized through application of a high throughput sequencing technique in human embryonic stem cells. Subsequent studies have shown the role of this microRNA in the carcinogenesis. miR-1246 has been found to exert oncogenic roles in colorectal, breast, renal, oral, laryngeal, pancreatic and ovarian cancers as well as melanoma and glioma. In lung, cervical and liver cancers, studies have reported contradictory results regarding the role of miR-1246. miR-1246 has been reported to regulate activity of RAF/MEK/ERK, GSK3β, Wnt/β-catenin, JAK/STAT, PI3K/AKT, THBS2/MMP and NOTCH2 pathways. In addition to affecting cell cycle progression and proliferation, miR-1246 can influence stemness and resistance of cancer cells to therapeutics. In the current review, we describe the summary of in vitro and in vivo studies about the influence of miR-1246 in carcinogenesis in addition to studies that measured expression levels of miR-1246 in clinical samples.

A New Antitumor Direction: Tumor-Specific Endothelial Cells

Targeting tumor blood vessels is an important strategy for tumor therapies. At present, antiangiogenic drugs are known to have significant clinical effects, but severe drug resistance and side effects also occur. Therefore, new specific targets for tumor and new treatment methods must be developed. Tumor-specific endothelial cells (TECs) are the main targets of antiangiogenic therapy. This review summarizes the differences between TECs and normal endothelial cells, assesses the heterogeneity of TECs, compares tumorigenesis and development between TECs and normal endothelial cells, and explains the interaction between TECs and the tumor microenvironment. A full and in-depth understanding of TECs may provide new insights for specific antitumor angiogenesis therapies.