Myc-associated zinc finger protein (MAZ) is regulated by miR-125b and mediates VEGF-induced angiogenesis in glioblastoma

Recent advances and future directions on small molecule VEGFR inhibitors in oncological conditions

"A journey of mixed emotions" is a quote that best describes the progress chart of vascular endothelial growth factor receptor (VEGFR) inhibitors as cancer therapeutics in the last decade. Exhilarated with the Food and Drug Administration (FDA) approvals of numerous VEGFR inhibitors coupled with the annoyance of encountering the complications associated with their use, drug discovery enthusiasts are on their toes with an unswerving determination to enhance the rate of translation of VEGFR inhibitors from preclinical to clinical stage. The recently crafted armory of VEGFR inhibitors is a testament to their growing dominance over other antiangiogenic therapies for cancer treatment. This review perspicuously underscores the earnest attempts of the researchers to extract the antiproliferative potential of VEGFR inhibitors through the design of mechanistically diverse structural assemblages. Moreover, this review encompasses sections on structural/molecular properties and physiological functions of VEGFR, FDA-approved VEGFR inhibitors, and hurdles restricting the activity range/clinical applicability of VEGFR targeting antitumor agents. In addition, tactics to overcome the limitations of VEGFR inhibitors are discussed. A clear-cut viewpoint transmitted through this compilation can provide practical directions to push the cart of VEGFR inhibitors to advanced-stage clinical investigations in diverse malignancies.

Insights into the roles of non-coding RNAs and angiogenesis in glioblastoma: An overview of current research and future perspectives

Glioblastoma (GBM) is a highly aggressive type of primary brain cancer with a poor prognosis, and despite intensive research, survival rates have not significantly improved. Non-coding RNAs (ncRNAs) are emerging as critical regulators of GBM pathogenesis, including angiogenesis, which is essential for tumor growth and invasion. MicroRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) have been identified as regulators of angiogenesis in GBM. miRNAs such as miR-21, miR-10b, and miR-26a promote angiogenesis by targeting anti-angiogenic factors, while lncRNAs such as H19 and MALAT1 inhibit angiogenesis by regulating pro-angiogenic factors. CircRNAs, such as circSMARCA5 and circBACH2, also regulate angiogenesis through various mechanisms. Similarly, signaling pathways such as the vascular endothelial growth factor (VEGF) pathway play critical roles in angiogenesis and have been targeted for GBM therapy. However, resistance to anti-angiogenic therapies is a significant obstacle in clinical practice. Developing novel therapeutic strategies targeting ncRNAs and angiogenesis is a promising approach for GBM. Potential targets include miRNAs, lncRNAs, circRNAs, and downstream signaling pathways that regulate angiogenesis. This review highlights the critical roles of ncRNAs and angiogenesis in GBM pathogenesis and the potential for new therapeutic strategies targeting these pathways to improve the prognosis and quality of life for GBM patients.

Engineered smart materials for RNA based molecular therapy to treat Glioblastoma

Glioblastoma (GBM) is an aggressive malignancy of the central nervous system (CNS) that remains incurable despite the multitude of improvements in cancer therapeutics. The conventional chemo and radiotherapy post-surgery have only been able to improve the prognosis slightly; however, the development of resistance and/or tumor recurrence is almost inevitable. There is a pressing need for adjuvant molecular therapies that can successfully and efficiently block tumor progression. During the last few decades, non-coding RNAs (ncRNAs) have emerged as key players in regulating various hallmarks of cancer including that of GBM. The levels of many ncRNAs are dysregulated in cancer, and ectopic modulation of their levels by delivering antagonists or overexpression constructs could serve as an attractive option for cancer therapy. The therapeutic potential of several types of ncRNAs, including miRNAs, lncRNAs, and circRNAs, has been validated in both in vitro and in vivo models of GBM. However, the delivery of these RNA-based therapeutics is highly challenging, especially to the tumors of the brain as the blood-brain barrier (BBB) poses as a major obstacle, among others. Also, since RNA is extremely fragile in nature, careful considerations must be met while designing a delivery agent. In this review we have shed light on how ncRNA therapy can overcome the limitations of its predecessor conventional therapy with an emphasis on smart nanomaterials that can aide in the safe and targeted delivery of nucleic acids to treat GBM. Additionally, critical gaps that currently exist for successful transition from viral to non-viral vector delivery systems have been identified. Finally, we have provided a perspective on the future directions, potential pathways, and target areas for achieving rapid clinical translation of, RNA-based macromolecular therapy to advance the effective treatment of GBM and other related diseases.

Genome-wide functional integration identified MAZ-controlled RPS14 dysregulation in hepatocellular carcinoma

Chronic infection with Hepatitis B virus (HBV) significantly increases the risk of hepatocellular carcinoma (HCC), particularly in Eastern Asia. However, only a subset of individuals with chronic HBV infection develop HCC, suggesting the role for genetic factors in HCC etiology. Despite genome-wide association studies (GWASs) identifying multiple single nucleotide polymorphisms (SNPs) associated with HBV-related HCC susceptibility, the underlying mechanisms and causal genetic polymorphisms remain largely unclear. To address this, we developed The Updated Integrative Functional Genomics Approach (TUIFGA), an methodology that combines data from transcription factor (TF) cistromics, ATAC-seq, DNAase-seq, and the 1000 Genomes Project to identify cancer susceptibility SNPs within TF-binding sites across human genome. Using TUIFGA, we discovered SNP rs13170300 which located in the TF MAZ binding motif of RPS14. The RPS14 rs13170300 was significantly associated with HCC risk in two case-control sets, with the T allele as the protective allele (Shandong discovery set: TT OR = 0.60, 95% CI = 0.49-0.74, P = 1.0 × 10-6; CT OR = 0.69, 95% CI = 0.55-0.86, P = 0.001; Jiangsu validation set: TT OR = 0.70, 95% CI = 0.56-0.87, P = 0.001; CT OR = 0.65, 95% CI = 0.53-0.82, P = 1.6 × 10-4). SNP rs13170300 affected MAZ binding in the RPS14 promoter, resulting in allele-specific changes in gene expression. RPS14 functions as a novel oncogene in HCC, specifically via activating the AKT signaling. Our findings present important insights into the functional genetics underlying HBV-related HCC development and may contribute to personalized approaches for cancer prevention and novel therapeutics.

Flavonoid Rutin Presented Anti-Glioblastoma Activity Related to the Modulation of Onco miRNA-125b Expression and STAT3 Signaling and Impact on Microglia Inflammatory Profile

Glioblastoma (GBM) is the most aggressive and treatment-resistant brain tumor. In the GBM microenvironment, interaction with microglia is associated with the dysregulation of cytokines, chemokines, and miRNAs, contributing to angiogenesis, proliferation, anti-apoptosis, and chemoresistance. The flavonoid rutin can inhibit glioma cell growth associated with microglial activation and production of pro-inflammatory mediators by mechanisms that are still poorly understood. The present study investigated the effect of rutin on viability, regulation of miRNA-125b, and the STAT3 expression in GBM cells, as well as the effects on the modulation of the inflammatory profile and STAT3 expression in microglia during indirect interaction with GBM cells. Human GL15-GBM cells and human C20 microglia were treated or not with rutin for 24 h. Rutin (30-50 μM) significantly reduced the viability of GL15 cells; however, it did not affect the viability of microglia. Rutin (30 μM) significantly reduced the expression of miRNA-125b in the cells and secretome and STAT3 expression. Microglia submitted to the conditioned medium from GBM cells treated with rutin showed reactive morphology associated with reduced expression of IL-6, TNF, and STAT3. These results reiterate the anti-glioma effects of the flavonoid, which may also modulate microglia towards a more responsive anti-tumor phenotype, constituting a promising molecule for adjuvant therapy to GBM.

Single-cell RNA sequencing analysis identifies one subpopulation of endothelial cells that proliferates and another that undergoes the endothelial-mesenchymal transition in regenerating pig hearts

Background: In our previous work, we demonstrated that when newborn pigs undergo apical resection (AR) on postnatal day 1 (P1), the animals' hearts were completely recover from a myocardial infarction (MI) that occurs on postnatal day 28 (P28); single-nucleus RNA sequencing (snRNAseq) data suggested that this recovery was achieved by regeneration of pig cardiomyocyte subpopulations in response to MI. However, coronary vasculature also has a key role in promoting cardiac repair. Method: Thus, in this report, we used autoencoder algorithms to analyze snRNAseq data from endothelial cells (ECs) in the hearts of the same animals. Main results: Our results identified five EC clusters, three composed of vascular ECs (VEC1-3) and two containing lymphatic ECs (LEC1-2). Cells from VEC1 expressed elevated levels of each of five cell-cyclespecific markers (Aurora Kinase B [AURKB], Marker of Proliferation Ki-67 [MKI67], Inner Centromere Protein [INCENP], Survivin [BIRC5], and Borealin [CDCA8]), as well as a number of transcription factors that promote EC proliferation, while (VEC3 was enriched for genes that regulate intercellular junctions, participate in transforming growth factor β (TGFβ), bone morphogenic protein (BMP) signaling, and promote the endothelial mesenchymal transition (EndMT). The remaining VEC2 did not appear to participate directly in the angiogenic response to MI, but trajectory analyses indicated that it may serve as a reservoir for the generation of VEC1 and VEC3 ECs in response to MI. Notably, only the VEC3 cluster was more populous in regenerating (i.e., ARP1MIP28) than non-regenerating (i.e., MIP28) hearts during the 1-week period after MI induction, which suggests that further investigation of the VEC3 cluster could identify new targets for improving myocardial recovery after MI. Histological analysis of KI67 and EndMT marker PDGFRA demonstrated that while the expression of proliferation of endothelial cells was not significantly different, expression of EndMT markers was significantly higher among endothelial cells of ARP1MIP28 hearts compared to MIP28 hearts, which were consistent with snRNAseq analysis of clusters VEC1 and VEC3. Furthermore, upregulated secrete genes by VEC3 may promote cardiomyocyte proliferation via the Pi3k-Akt and ERBB signaling pathways, which directly contribute to cardiac muscle regeneration. Conclusion: In regenerative heart, endothelial cells may express EndMT markers, and this process could contribute to regeneration via a endothelial-cardiomyocyte crosstalk that supports cardiomyocyte proliferation.

Spatial multiomics of arterial regions from cardiac allograft vasculopathy rejected grafts reveal novel insights into the pathogenesis of chronic antibody-mediated rejection

Cardiac allograft vasculopathy (CAV) causes late graft failure and mortality after heart transplantation. Donor-specific antibodies (DSAs) lead to chronic endothelial cell injury, inflammation, and arterial intimal thickening. In this study, GeoMx digital spatial profiling was used to analyze arterial areas of interest (AOIs) from CAV+DSA+ rejected cardiac allografts (N = 3; 22 AOIs total). AOIs were categorized based on CAV neointimal thickening and underwent whole transcriptome and protein profiling. By comparing our transcriptomic data with that of healthy control vessels of rapid autopsy myocardial tissue, we pinpointed specific pathways and transcripts indicative of heightened inflammatory profiles in CAV lesions. Moreover, we identified protein and transcriptomic signatures distinguishing CAV lesions exhibiting low and high neointimal lesions. AOIs with low neointima showed increased markers for activated inflammatory infiltrates, endothelial cell activation transcripts, and gene modules involved in metalloproteinase activation and TP53 regulation of caspases. Inflammatory and apoptotic proteins correlated with inflammatory modules in low neointima AOIs. High neointima AOIs exhibited elevated TGFβ-regulated transcripts and modules enriched for platelet activation/aggregation. Proteins associated with growth factors/survival correlated with modules enriched for proliferation/repair in high neointima AOIs. Our findings reveal novel insight into immunological mechanisms mediating CAV pathogenesis.

The Significant Role of microRNAs in Gliomas Angiogenesis: A Particular Focus on Molecular Mechanisms and Opportunities for Clinical Application

MicroRNAs (miRNAs) are non-coding RNAs with only 20-22 nucleic acids that inhibit gene transcription and translation by binding to mRNA. MiRNAs have a diverse set of target genes and can alter most physiological processes, including cell cycle checkpoints, cell survival, and cell death mechanisms, affecting the growth, development, and invasion of various cancers, including gliomas. So optimum management of miRNA expression is essential for preserving a normal biological environment. Due to their small size, stability, and capability of specifically targeting oncogenes, miRNAs have emerged as a promising marker and new biopharmaceutical targeted therapy for glioma patients. This review focuses on the most common miRNAs associated with gliomagenesis and development by controlling glioma-determining markers such as angiogenesis. We also summarized the recent research about miRNA effects on signaling pathways, their mechanistic role and cellular targets in the development of gliomas angiogenesis. Strategies for miRNA-based therapeutic targets, as well as limitations in clinical applications, are also discussed.

The Prognostic Value of ASPHD1 and ZBTB12 in Colorectal Cancer: A Machine Learning-Based Integrated Bioinformatics Approach

Introduction: Colorectal cancer (CRC) is a common cancer associated with poor outcomes, underscoring a need for the identification of novel prognostic and therapeutic targets to improve outcomes. This study aimed to identify genetic variants and differentially expressed genes (DEGs) using genome-wide DNA and RNA sequencing followed by validation in a large cohort of patients with CRC. Methods: Whole genome and gene expression profiling were used to identify DEGs and genetic alterations in 146 patients with CRC. Gene Ontology, Reactom, GSEA, and Human Disease Ontology were employed to study the biological process and pathways involved in CRC. Survival analysis on dysregulated genes in patients with CRC was conducted using Cox regression and Kaplan-Meier analysis. The STRING database was used to construct a protein-protein interaction (PPI) network. Moreover, candidate genes were subjected to ML-based analysis and the Receiver operating characteristic (ROC) curve. Subsequently, the expression of the identified genes was evaluated by Real-time PCR (RT-PCR) in another cohort of 64 patients with CRC. Gene variants affecting the regulation of candidate gene expressions were further validated followed by Whole Exome Sequencing (WES) in 15 patients with CRC. Results: A total of 3576 DEGs in the early stages of CRC and 2985 DEGs in the advanced stages of CRC were identified. ASPHD1 and ZBTB12 genes were identified as potential prognostic markers. Moreover, the combination of ASPHD and ZBTB12 genes was sensitive, and the two were considered specific markers, with an area under the curve (AUC) of 0.934, 1.00, and 0.986, respectively. The expression levels of these two genes were higher in patients with CRC. Moreover, our data identified two novel genetic variants-the rs925939730 variant in ASPHD1 and the rs1428982750 variant in ZBTB1-as being potentially involved in the regulation of gene expression. Conclusions: Our findings provide a proof of concept for the prognostic values of two novel genes-ASPHD1 and ZBTB12-and their associated variants (rs925939730 and rs1428982750) in CRC, supporting further functional analyses to evaluate the value of emerging biomarkers in colorectal cancer.

MicroRNAs in Tumor Endothelial Cells: Regulation, Function and Therapeutic Applications

Tumor endothelial cells (TECs) are key stromal components of the tumor microenvironment, and are essential for tumor angiogenesis, growth and metastasis. Accumulating evidence has shown that small single-stranded non-coding microRNAs (miRNAs) act as powerful endogenous regulators of TEC function and blood vessel formation. This systematic review provides an up-to-date overview of these endothelial miRNAs. Their expression is mainly regulated by hypoxia, pro-angiogenic factors, gap junctions and extracellular vesicles, as well as long non-coding RNAs and circular RNAs. In preclinical studies, they have been shown to modulate diverse fundamental angiogenesis-related signaling pathways and proteins, including the vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) pathway; the rat sarcoma virus (Ras)/rapidly accelerated fibrosarcoma (Raf)/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway; the phosphoinositide 3-kinase (PI3K)/AKT pathway; and the transforming growth factor (TGF)-β/TGF-β receptor (TGFBR) pathway, as well as krüppel-like factors (KLFs), suppressor of cytokine signaling (SOCS) and metalloproteinases (MMPs). Accordingly, endothelial miRNAs represent promising targets for future anti-angiogenic cancer therapy. To achieve this, it will be necessary to further unravel the regulatory and functional networks of endothelial miRNAs and to develop safe and efficient TEC-specific miRNA delivery technologies.

16p11.2 haploinsufficiency reduces mitochondrial biogenesis in brain endothelial cells and alters brain metabolism in adult mice

Neurovascular abnormalities in mouse models of 16p11.2 deletion autism syndrome are reminiscent of alterations reported in murine models of glucose transporter deficiency, including reduced brain angiogenesis and behavioral alterations. Yet, whether cerebrovascular alterations in 16p11.2^df/+ mice affect brain metabolism is unknown. Here, we report that anesthetized 16p11.2^df/+ mice display elevated brain glucose uptake, a phenomenon recapitulated in mice with endothelial-specific 16p11.2 haplodeficiency. Awake 16p11.2^df/+ mice display attenuated relative fluctuations of extracellular brain glucose following systemic glucose administration. Targeted metabolomics on cerebral cortex extracts reveals enhanced metabolic responses to systemic glucose in 16p11.2^df/+ mice that also display reduced mitochondria number in brain endothelial cells. This is not associated with changes in mitochondria fusion or fission proteins, but 16p11.2^df/+ brain endothelial cells lack the splice variant NT-PGC-1α, suggesting defective mitochondrial biogenesis. We propose that altered brain metabolism in 16p11.2^df/+ mice is compensatory to endothelial dysfunction, shedding light on previously unknown adaptative responses.

PCGF6/MAX/KDM5D facilitates MAZ/CDK4 axis expression and pRCC progression by hypomethylation of the DNA promoter

Polycomb group RING finger protein 6 (PCGF6) plays an important role as a regulator of transcription in a variety of cellular processes, including tumorigenesis. However, the function and expression of PCGF6 in papillary RCC (pRCC) remain unclear. In the present study, we found that PCGF6 expression was significantly elevated in pRCC tissues, and high expression of PCGF6 was associated with poor survival of patients with pRCC. The overexpression of PCGF6 promoted while depletion of PCGF6 depressed the proliferation of pRCC cells in vitro. Interestingly, myc-related zinc finger protein (MAZ), a downstream molecular of PCGF6, was upregulated in pRCC with hypomethylation promoter. Mechanically, PCGF6 promoted MAZ expression by interacting with MAX and KDM5D to form a complex, and MAX recruited PCGF6 and KDM5D to the CpG island of the MAZ promoter and facilitated H3K4 histone demethylation. Furthermore, CDK4 was a downstream molecule of MAZ that participated in PCGF6/MAZ-regulated progression of pRCC. These results indicated that the upregulation of PCGF6 facilitated MAZ/CDK4 axis expression and pRCC progression by hypomethylation of the MAZ promoter. The PCGF6/MAZ/CDK4 regulatory axis may be a potential target for the treatment of ccRCC.

Target c-Myc to treat pancreatic cancer

C-Myc overexpression is a common finding in pancreatic cancer and predicts the aggressive behavior of cancer cells. It binds to the promoter of different genes, thereby regulating their transcription. C-Myc is downstream of KRAS and interacts with several oncogenic and proliferative pathways in pancreatic cancer. C-Myc enhances aerobic glycolysis in cancer cells and regulates glutamate biosynthesis from glutamine. It provides enough energy for cancer cells' metabolism and sufficient substrate for the synthesis of organic molecules. C-Myc overexpression is associated with chemoresistance, intra-tumor angiogenesis, epithelial-mesenchymal transition (EMT), and metastasis in pancreatic cancer. Despite its title, c-Myc is not "undruggable" and recent studies unveiled that it can be targeted, directly or indirectly. Small molecules that accelerate c-Myc ubiquitination and degradation have been effective in preclinical studies. Small molecules that hinder c-Myc-MAX heterodimerization or c-Myc/MAX/DNA complex formation can functionally inhibit c-Myc. In addition, c-Myc can be targeted through transcriptional, post-transcriptional, and translational modifications.

TUG1/MAZ/FTH1 Axis Attenuates the Antiglioma Effect of Dihydroartemisinin by Inhibiting Ferroptosis

Glioma is the most common primary intracranial malignant tumor in the brain. Currently, due to the limited treatment methods, the clinical outcome of patients with standard surgery combined with radiotherapy and chemotherapy is not satisfactory. Therefore, we urgently need to develop effective drugs to solve this problem. As a semisynthetic derivative of artemisinin, dihydroartemisinin (DHA) has been proved to have antitumor activity in glioma, which can induce apoptosis and inhibit the proliferation, migration, and invasion of glioma cells. In recent years, ferroptosis has been identified as another antitumor mechanism of DHA. Researchers have shown that DHA could promote ferroptosis in glioma cells. However, the specific molecular mechanisms of ferroptosis induced by DHA need more exploration. In this study, we found DHA could induce ferroptosis with ROS production and lipid peroxidation in glioma cells. Low expression of GPX4 and high expression of HMOX1 were identified in DHA treated glioma cells. Surprisingly, we found FTH1, a negative regulator of ferroptosis, upregulated in DHA treated glioma cells. It indicated that there should be some mechanisms that may cause ferroptosis attenuation in DHA treated glioma cells. For the first time, we confirmed that MYC-associated zinc finger protein (MAZ) could actively regulate FTH1 by binding to FTH1 promoter by CHIP assay. MAZ was further identified as the direct target of long noncoding RNA (lncRNA) TUG1 through luciferase assay. Downregulated expression of TUG1 and upregulated expression of MAZ were identified in DHA treated glioma cells. TUG1 overexpression or inhibition of FTH1 expression could enhance the antiglioma effect of DHA in vitro and in vivo, providing a promising strategy to enhance the antitumor effect of DHA in glioma.

A Cuproptosis Activation Scoring model predicts neoplasm-immunity interactions and personalized treatments in glioma

Gliomas are malignant tumors in the central nervous system. Cuproptosis is a newly discovered cell death mechanism targeting lipoylated tricarboxylic acid cycle proteins. Previous studies have found that cuproptosis participates in tumor progression, but its role in gliomas is still elusive. Here, we systematically explored the bulk-tumor and single-cell transcriptome data to reveal its role in gliomas. The cuproptosis activity score (CuAS) was constructed based on cuproptosis-related genes, and machine learning techniques validated the score stability. High CuAS gliomas were more likely to have a poor prognosis and an aggressive mesenchymal (MES) subtype. Subsequently, the SCENIC algorithm predicted 20 CuAS-related transcription factors (TFs) in gliomas. Function enrichment and microenvironment analyses found that CuAS was associated with tumor immune infiltration. Accordingly, intercellular communications between neoplasm and immunity were explored by the R package "Cellchat". Five signaling pathways and 8 ligand-receptor pairs including ICAM1, ITGAX, ITGB2, ANXA1-FRR1, and the like, were identified to suggest how cuproptosis activity connected neoplastic and immune cells. Critically, 13 potential drugs targeting high CuAs gliomas were predicted according to the CTRP and PRISM databases, including oligomycin A, dihydroartemisinin, and others. Taken together, cuproptosis is involved in glioma aggressiveness, neoplasm-immune interactions, and may be used to assist in drug selection.

Recent insights into the microRNA-dependent modulation of gliomas from pathogenesis to diagnosis and treatment

Gliomas are the most lethal primary brain tumors in adults. These highly invasive tumors have poor 5-year survival for patients. Gliomas are principally characterized by rapid diffusion as well as high levels of cellular heterogeneity. However, to date, the exact pathogenic mechanisms, contributing to gliomas remain ambiguous. MicroRNAs (miRNAs), as small noncoding RNAs of about 20 nucleotides in length, are known as chief modulators of different biological processes at both transcriptional and posttranscriptional levels. More recently, it has been revealed that these noncoding RNA molecules have essential roles in tumorigenesis and progression of multiple cancers, including gliomas. Interestingly, miRNAs are able to modulate diverse cancer-related processes such as cell proliferation and apoptosis, invasion and migration, differentiation and stemness, angiogenesis, and drug resistance; thus, impaired miRNAs may result in deterioration of gliomas. Additionally, miRNAs can be secreted into cerebrospinal fluid (CSF), as well as the bloodstream, and transported between normal and tumor cells freely or by exosomes, converting them into potential diagnostic and/or prognostic biomarkers for gliomas. They would also be great therapeutic agents, especially if they could cross the blood–brain barrier (BBB). Accordingly, in the current review, the contribution of miRNAs to glioma pathogenesis is first discussed, then their glioma-related diagnostic/prognostic and therapeutic potential is highlighted briefly.

Tumor-targeted miRNA nanomedicine for overcoming challenges in immunity and therapeutic resistance

miRNA are critical messengers in the tumor microenvironment (TME) that influence various processes leading to immune suppression, tumor progression, metastasis and resistance. Strategies to modulate miRNAs in the TME have important implications in overcoming these challenges. However, miR delivery to specific cells in the TME has been challenging. This review discusses nanomedicine strategies to achieve cell-specific delivery of miRNAs. The key goal of delivery is to activate the tumor immune landscape as well as to prevent chemotherapy resistance. Specifically, the use of hyaluronic acid-based nanoparticle miRNA delivery to the TME is discussed. The discussion is focused on miRNA-125b for reprogramming tumor-associated macrophages to overcome immunosuppression and miRNA-let-7b to overcome resistance to anticancer chemotherapeutics because both these miRNAs have been extensively evaluated for delivery with hyaluronic acid-based delivery systems.

AGO-RBP crosstalk on target mRNAs: Implications in miRNA-guided gene silencing and cancer

MicroRNAs (miRNAs) and RNA-binding proteins (RBPs) are important regulators of mRNA translation and stability in eukaryotes. While miRNAs can only bind their target mRNAs in association with Argonaute proteins (AGOs), RBPs directly bind their targets either as single entities or in complex with other RBPs to control mRNA metabolism. miRNA binding in 3' untranslated regions (3' UTRs) of mRNAs facilitates an intricate network of interactions between miRNA-AGO and RBPs, thus determining the fate of overlapping targets. Here, we review the current knowledge on the interplay between miRNA-AGO and multiple RBPs in different cellular contexts, the rules underlying their synergism and antagonism on target mRNAs, as well as highlight the implications of these regulatory modules in cancer initiation and progression.

Identification and Somatic Characterization of the Germline PTEN Promoter Variant rs34149102 in a Family with Gastrointestinal and Breast Tumors

Genetic variants located in non-coding regions can affect processes that regulate protein expression, functionally contributing to human disease. Germline heterozygous mutations in the non-coding region of the PTEN gene have been previously identified in patients with PTEN hamartoma tumor syndrome (PHTS) diagnosed with breast, thyroid, and/or endometrial cancer. In this study, we report a PTEN promoter variant (rs34149102 A allele) that was identified by direct sequencing in an Italian family with a history of gastroesophageal junction (GEJ) adenocarcinoma and breast cancer. In order to investigate the putative functional role of the rs34149102 A allele variant, we evaluated the status of PTEN alterations at the somatic level. We found that PTEN protein expression was absent in the GEJ adenocarcinoma tissue of the index case. Moreover, we detected the occurrence of copy number loss involving the PTEN rs34149102 major C allele in tumor tissue, revealing that the second allele was somatically inactivated. This variant is located within an active regulatory region of the PTEN core promoter, and in silico analysis suggests that it may affect the binding of the nuclear transcription factor MAZ and hence PTEN expression. Overall, these results reveal the functional role of the PTEN promoter rs34149102 A allele variant in the modulation of PTEN protein expression and highlight its contribution to hereditary cancer risk.

Angioregulatory role of miRNAs and exosomal miRNAs in glioblastoma pathogenesis

Glioblastoma (GB) is a highly aggressive cancer of the central nervous system, occurring in the brain or spinal cord. Many factors such as angiogenesis are associated with GB development. Angiogenesis is a procedure by which the pre-existing blood vessels create new vessels that play an essential role in health and disease, including tumors. Also, angiogenesis is one of the significant factors thought to be responsible for treatment resistance in many tumors, including GB. Hence, an improved understanding of the molecular processes underlying GB angiogenesis will pave the way for developing potential new treatments. Recently, it has been found that microRNAs (miRNAs) and exosomal miRNAs have a crucial role in inducing or inhibiting the angiogenesis process in GB development. A better knowledge of the miRNA's regulation pathway in the angiogenesis process in cancer offers unique mechanistic insight into the mechanism of tumor-associated neovascularization. Because of advancements in miRNA characterization and delivery methods, miRNAs can also be employed in clinical settings as potential biomarkers for anti-angiogenic treatment response as well as therapies targeting tumor angiogenesis. The recent finding and insights about miRNAs' angioregulatory role and exosomal miRNAs in GB are provided throughout the review. Also, we discuss the new concept of miRNAs-based therapies for GB in the future.

Roles of Myc-associated zinc finger protein in malignant tumors

As an important transcription factor that is widely expressed in most tissues of the human body, Myc-associated zinc finger protein (MAZ) has been reported highly expressed in many malignant tumors and thought to be a promising therapeutic target for cancer treatment. In this review, we aim to offer a comprehensive understanding of MAZ regulation in malignant tumors. The carboxy terminal of MAZ protein contains six C2H2 zinc fingers, and its regulation of transcription is based on the interaction between the GC-rich DNA binding sites of target genes and its carboxy-terminal zinc finger motifs. MAZ protein has been found to activate or inhibit the transcriptional initiation process of many target genes, as well as play an important role in the transcriptional termination process of some target genes, so MAZ poses dual regulatory functions in the initiation and termination process of gene transcription. Through the transcriptional regulation of c-myc and Ras gene family, MAZ poses an important role in the occurrence and development of breast cancer, pancreatic cancer, prostate cancer, glioblastoma, neuroblastoma, and other malignant tumors. Our review shows a vital role of MAZ in many malignant tumors and provides novel insight for cancer diagnosis and treatment.

The Role of MicroRNAs in Therapeutic Resistance of Malignant Primary Brain Tumors

Brain tumors in children and adults are challenging tumors to treat. Malignant primary brain tumors (MPBTs) such as glioblastoma have very poor outcomes, emphasizing the need to better understand their pathogenesis. Developing novel strategies to slow down or even stop the growth of brain tumors remains one of the major clinical challenges. Modern treatment strategies for MPBTs are based on open surgery, chemotherapy, and radiation therapy. However, none of these treatments, alone or in combination, are considered effective in controlling tumor progression. MicroRNAs (miRNAs) are 18-22 nucleotide long endogenous non-coding RNAs that regulate gene expression at the post-transcriptional level by interacting with 3'-untranslated regions (3'-UTR) of mRNA-targets. It has been proven that miRNAs play a significant role in various biological processes, including the cell cycle, apoptosis, proliferation, differentiation, etc. Over the last decade, there has been an emergence of a large number of studies devoted to the role of miRNAs in the oncogenesis of brain tumors and the development of resistance to radio- and chemotherapy. Wherein, among the variety of molecules secreted by tumor cells into the external environment, extracellular vesicles (EVs) (exosomes and microvesicles) play a special role. Various elements were found in the EVs, including miRNAs, which can be transported as part of these EVs both between neighboring cells and between remotely located cells of different tissues using biological fluids. Some of these miRNAs in EVs can contribute to the development of resistance to radio- and chemotherapy in MPBTs, including multidrug resistance (MDR). This comprehensive review examines the role of miRNAs in the resistance of MPBTs (e.g., high-grade meningiomas, medulloblastoma (MB), pituitary adenomas (PAs) with aggressive behavior, and glioblastoma) to chemoradiotherapy and pharmacological treatment. It is believed that miRNAs are future therapeutic targets in MPBTs and such the role of miRNAs needs to be critically evaluated to focus on solving the problems of resistance to therapy this kind of human tumors.

Roles of Non-coding RNAs and Angiogenesis in Glioblastoma

One of the significant hallmarks of cancer is angiogenesis. It has a crucial function in tumor development and metastasis. Thus, angiogenesis has become one of the most exciting targets for drug development in cancer treatment. Here we discuss the regulatory effects on angiogenesis in glioblastoma (GBM) of non-coding RNAs (ncRNAs), including long ncRNA (lncRNA), microRNA (miRNA), and circular RNA (circRNA). These ncRNAs may function in trans or cis forms and modify gene transcription by various mechanisms, including epigenetics. NcRNAs may also serve as crucial regulators of angiogenesis-inducing molecules. These molecules include, metalloproteinases, cytokines, several growth factors (platelet-derived growth factor, vascular endothelial growth factor, fibroblast growth factor, hypoxia-inducible factor-1, and epidermal growth factor), phosphoinositide 3-kinase, mitogen-activated protein kinase, and transforming growth factor signaling pathways.

Role of microRNAs in glioblastoma

Glioblastoma is the most common and aggressive primary human brain cancer. MicroRNAs (miRNAs) are a set of small endogenous non-coding RNA molecules which play critical roles in different biological processes including cancer. The realization of miRNA regulatory functions in GBM has demonstrated that these molecules play a critical role in its initiation, progression and response to therapy. In this review we discuss the studies related to miRNA discovery and function in glioblastoma. We first summarize the typical miRNAs and their roles in GBM. Then we debate the potential for miRNA-based therapy for glioblastoma, including various delivery strategies. We surmise that future directions identified by these studies will point towards the necessity for therapeutic development and optimization to improve the outcomes for patients with glioblastoma.

Noncoding RNAs in Glioblastoma: Emerging Biological Concepts and Potential Therapeutic Implications

Simple Summary

Since the completion of the Human Genome Project, noncoding RNAs (ncRNAs) have emerged as an important class of genetic regulators. Several classes of ncRNAs, which include microRNAs (miRNAs), long noncoding RNAs (lncRNAs), circular RNAs (circRNAs), and piwi-interacting RNAs (piRNAs), have been shown to play important roles in controlling developmental and disease processes. In this article, we discuss the potential roles of ncRNAs in regulating glioblastoma (GBM) formation and progression as well as potential strategies to exploit the diagnostic and therapeutic potential of ncRNAs in GBM.

Abstract

Noncoding RNAs (ncRNAs) have emerged as a novel class of genomic regulators, ushering in a new era in molecular biology. With the advent of advanced genetic sequencing technology, several different classes of ncRNAs have been uncovered, including microRNAs (miRNAs), long noncoding RNAs (lncRNAs), circular RNAs (circRNAs), and piwi-interacting RNAs (piRNAs), which have been linked to many important developmental and disease processes and are being pursued as clinical and therapeutic targets. Molecular phenotyping studies of glioblastoma (GBM), the most common and lethal cancer of the adult brain, revealed that several ncRNAs are frequently dysregulated in its pathogenesis. Additionally, ncRNAs regulate many important aspects of glioma biology including tumour cell proliferation, migration, invasion, apoptosis, angiogenesis, and self-renewal. Here, we present an overview of the biogenesis of the different classes of ncRNAs, discuss their biological roles, as well as their relevance to gliomagenesis. We conclude by discussing potential approaches to therapeutically target the ncRNAs in clinic.

Docosahexaenoic acid reverses the promoting effects of breast tumor cell-derived exosomes on endothelial cell migration and angiogenesis

AIM

As a natural compound, docosahexaenoic acid (DHA) exerts anti-cancer and anti-angiogenesis functions through exosomes; however, little is known about the molecular mechanisms.

MAIN METHODS

Breast cancer (BC) cells were treated with DHA (50 μM) and then tumor cell-derived exosomes (TDEs) were collected and characterized by electron microscopy, dynamic light scattering, and western blot analyses. By the time the cells were treated with DHA, RT-qPCR was used to investigate the expression of vascular endothelial growth factor (VEGF) and the selected pro- and anti-angiogenic microRNAs (miRNAs). The quantification of secreted VEGF protein was measured by enzyme-linked immunosorbent assay (ELISA). The effects of TDEs on endothelial cell angiogenesis were explored by transwell cell migration and in vitro vascular tube formation assays.

KEY FINDINGS

DHA treatment caused a significant and time-dependent decrease in the expression and secretion of VEGF in/from BC cells. This also increased expression of anti-angiogenic miRNAs (i.e. miR-34a, miR-125b, miR-221, and miR-222) while decreased levels of pro-angiogenic miRNAs (i.e. miR-9, miR-17-5p, miR-19a, miR-126, miR-130a, miR-132, miR-296, and miR-378) in exosomes derived from DHA-treated BC cells, TDE (DHA+). While treatment with exosomes (100 μg/ml) obtained from untreated BC cells, TDE (DHA-), enhanced the expression of VEGF-A in human umbilical vein endothelial cells (HUVECs), incubation with DHA or TDE (DHA+) led to the significant decrease of VEGF-A transcript level in these cells. We indicated that the incubation with TDE (DHA+) could significantly decrease endothelial cell proliferation and migration and also the length and number of tubes made by HUVECs in comparison with endothelial cells incubated with exosomes obtained from untreated BC cells.

SIGNIFICANCE

DHA alters angiogenesis by shifting the up-regulation of exosomal miRNA contents from pro-angiogenic to anti-angiogenic, resulting in the inhibition of endothelial cell angiogenesis. These data can help to figure out DHA's anti-cancer function, maybe its use in cancer therapy.

Therapeutically Significant MicroRNAs in Primary and Metastatic Brain Malignancies

Simple Summary

The overall survival of brain cancer patients remains grim, with conventional therapies such as chemotherapy and radiotherapy only providing marginal benefits to patient survival. Cancers are complex, with multiple pathways being dysregulated simultaneously. Non-coding RNAs such as microRNA (miRNAs) are gaining importance due to their potential in regulating a variety of targets implicated in the pathology of cancers. This could be leveraged for the development of targeted and personalized therapies for cancers. Since miRNAs can upregulate and/or downregulate proteins, this review aims to understand the role of these miRNAs in primary and metastatic brain cancers. Here, we discuss the regulatory mechanisms of ten miRNAs that are highly dysregulated in glioblastoma and metastatic brain tumors. This will enable researchers to develop miRNA-based targeted cancer therapies and identify potential prognostic biomarkers.

Abstract

Brain cancer is one among the rare cancers with high mortality rate that affects both children and adults. The most aggressive form of primary brain tumor is glioblastoma. Secondary brain tumors most commonly metastasize from primary cancers of lung, breast, or melanoma. The five-year survival of primary and secondary brain tumors is 34% and 2.4%, respectively. Owing to poor prognosis, tumor heterogeneity, increased tumor relapse, and resistance to therapies, brain cancers have high mortality and poor survival rates compared to other cancers. Early diagnosis, effective targeted treatments, and improved prognosis have the potential to increase the survival rate of patients with primary and secondary brain malignancies. MicroRNAs (miRNAs) are short noncoding RNAs of approximately 18–22 nucleotides that play a significant role in the regulation of multiple genes. With growing interest in the development of miRNA-based therapeutics, it is crucial to understand the differential role of these miRNAs in the given cancer scenario. This review focuses on the differential expression of ten miRNAs (miR-145, miR-31, miR-451, miR-19a, miR-143, miR-125b, miR-328, miR-210, miR-146a, and miR-126) in glioblastoma and brain metastasis. These miRNAs are highly dysregulated in both primary and metastatic brain tumors, which necessitates a better understanding of their role in these cancers. In the context of the tumor microenvironment and the expression of different genes, these miRNAs possess both oncogenic and/or tumor-suppressive roles within the same cancer.

Recent Trends of microRNA Significance in Pediatric Population Glioblastoma and Current Knowledge of Micro RNA Function in Glioblastoma Multiforme

Central nervous system tumors are a significant problem for modern medicine because of their location. The explanation of the importance of microRNA (miRNA) in the development of cancerous changes plays an important role in this respect. The first papers describing the presence of miRNA were published in the 1990s. The role of miRNA has been pointed out in many medical conditions such as kidney disease, diabetes, neurodegenerative disorder, arthritis and cancer. There are several miRNAs responsible for invasiveness, apoptosis, resistance to treatment, angiogenesis, proliferation and immunology, and many others. The research conducted in recent years analyzing this group of tumors has shown the important role of miRNA in the course of gliomagenesis. These particles seem to participate in many stages of the development of cancer processes, such as proliferation, angiogenesis, regulation of apoptosis or cell resistance to cytostatics.

miR-524-5p inhibits angiogenesis through targeting WNK1 in colon cancer cells

There is increasing evidence that microRNA (miRNA) abnormity is involved in the occurrence and the development of various malignancies, including colon cancer. MiRNA-524-5p has been reported to possess anticancer activity in various tumors, which function is seldom investigated in colon cancer cells. The aim of this study was to explore the effect of the miRNA-524-5p/with-no-lysine kinase 1 (WNK1) system on angiogenesis in a colon cancer cell line (HT-29 and COLO205 cells) and further investigate the potential mechanisms. We found miRNA-524-5p expression was relatively high in COLO205 cells and relatively low in HT-29 cells. Elevating miRNA-524-5p expression inhibited proliferation, induced cycle arrest, diminished vascular endothelial growth factor production, and thereby suppressed angiogenesis in HT-29 cells. WNK1 silencing exerted the ability of antiangiogenesis in HT-29 cells. Besides, miRNA-524-5p deficiency-induced angiogenesis was impeded by WNK1 silence in COLO205 cells. In a murine tumor model, miRNA-524-5p agomir treatment significantly suppressed colon cancer tumorigenicity with the downregulation of WNK1 expression. In summary, our results indicated that miRNA-524-5p inhibited angiogenesis in colon cancer cells via targeting WNK1.NEW & NOTEWORTHY MiRNA-524-5p inhibited angiogenesis in colon cancer cells via targeting with-no-lysine kinase 1.

The Roles of miRNA in Glioblastoma Tumor Cell Communication: Diplomatic and Aggressive Negotiations

Glioblastoma (GBM) consists of a heterogeneous collection of competing cellular clones which communicate with each other and with the tumor microenvironment (TME). MicroRNAs (miRNAs) present various exchange mechanisms: free miRNA, extracellular vesicles (EVs), or gap junctions (GJs). GBM cells transfer miR-4519 and miR-5096 to astrocytes through GJs. Oligodendrocytes located in the invasion front present high levels of miR-219-5p, miR-219-2-3p, and miR-338-3p, all related to their differentiation. There is a reciprocal exchange between GBM cells and endothelial cells (ECs) as miR-5096 promotes angiogenesis after being transferred into ECs, whereas miR-145-5p acts as a tumor suppressor. In glioma stem cells (GSCs), miR-1587 and miR-3620-5p increase the proliferation and miR-1587 inhibits the hormone receptor co-repressor-1 (NCOR1) after EVs transfers. GBM-derived EVs carry miR-21 and miR-451 that are up-taken by microglia and monocytes/macrophages, promoting their proliferation. Macrophages release EVs enriched in miR-21 that are transferred to glioma cells. This bidirectional miR-21 exchange increases STAT3 activity in GBM cells and macrophages, promoting invasion, proliferation, angiogenesis, and resistance to treatment. miR-1238 is upregulated in resistant GBM clones and their EVs, conferring resistance to adjacent cells via the CAV1/EGFR signaling pathway. Decrypting these mechanisms could lead to a better patient stratification and the development of novel target therapies.

Role of microRNAs in remodeling the tumor microenvironment (Review)

MicroRNAs (miRNAs) are short non-coding RNAs that are known to regulate gene expression at the post-transcriptional level. miRNA expression is often deregulated in several human cancers, affecting the communication between tumor stroma and tumor cells, among other functions. Understanding the role of miRNAs in the tumor microenvironment is crucial for fully elucidating the molecular mechanisms underlying tumor progression and exploring novel diagnostic biomarkers and therapeutic targets. The present review focused on the role of miRNAs in remodeling the tumor microenvironment, with an emphasis on their impact on tumor growth, metastasis and resistance to treatment, as well as their potential clinical applications.

Silencing microRNA-221/222 cluster suppresses glioblastoma angiogenesis by suppressor of cytokine signaling-3-dependent JAK/STAT pathway

Angiogenesis is a major pathologic characteristic of glioblastoma, which is one aggressive primary brain tumor. MicroRNA-221/222 (miR-221/222) cluster has been previously reported to function importantly in malignant glioma biological process. The current study aims at evaluating the effects of miR-221/222 cluster on angiogenesis of glioblastoma cells. Microarray data were analyzed to select glioblastoma-associated differentially expressed genes, and dual-luciferase reporter assay was performed to assess targeting correlation between miR-221/222 cluster and suppressor of cytokine signaling-3 (SOCS3). Subsequently, the expression patterns of miR-221 and miR-222 in glioblastoma cells were identified. miR-221 and miR-222 were overexpressed or silenced in glioblastoma cells to identify the effect of miR-221/222 cluster in cell invasion, migration, proliferation, and angiogenesis. To define downstream pathway of miR-221/222 cluster or SOCS3 in glioblastoma, levels of Janus kinase (JAK)/signal transducers and activators of transcription (STAT) pathway-related proteins were assessed. Additionally, the functions of miR-221/222 on glioblastoma cell angiogenesis were measured in vivo with microvessel density assayed. miR-221 and miR-222 were expressed at a high level and SOCS3 was at a low level in glioblastoma. Downregulation of the miR-221/222 cluster diminished the invasion, migration, proliferation, and angiogenesis with reduced protein levels of matrix metalloproteinase-2 (MMP-2), MMP-9, and vascular endothelial growth factor in glioblastoma cells. Also, silencing miR-221/222 cluster reduced p-JAK2/JAK2 and p-STAT3/STAT3. Consistently, the inhibitory role of silencing miR-221/222 cluster on tumorigenesis of glioblastoma cells was confirmed in vivo. Collectively, the inhibition of miR-221/222 cluster could attenuate the glioblastoma angiogenesis through inactivation of the JAK/STAT pathway by upregulating SOCS3.

Therapeutic targeting of circ-CUX1/EWSR1/MAZ axis inhibits glycolysis and neuroblastoma progression

Aerobic glycolysis is a hallmark of metabolic reprogramming in tumor progression. However, the mechanisms regulating glycolytic gene expression remain elusive in neuroblastoma (NB), the most common extracranial malignancy in childhood. Herein, we identify that CUT‐like homeobox 1 (CUX1) and CUX1‐generated circular RNA (circ‐CUX1) contribute to aerobic glycolysis and NB progression. Mechanistically, p110 CUX1, a transcription factor generated by proteolytic processing of p200 CUX1, promotes the expression of enolase 1, glucose‐6‐phosphate isomerase, and phosphoglycerate kinase 1, while circ‐CUX1 binds to EWS RNA‐binding protein 1 (EWSR1) to facilitate its interaction with MYC‐associated zinc finger protein (MAZ), resulting in transactivation of MAZ and transcriptional alteration of CUX1 and other genes associated with tumor progression. Administration of an inhibitory peptide blocking circ‐CUX1‐EWSR1 interaction or lentivirus mediating circ‐CUX1 knockdown suppresses aerobic glycolysis, growth, and aggressiveness of NB cells. In clinical NB cases, CUX1 is an independent prognostic factor for unfavorable outcome, and patients with high circ‐CUX1 expression have lower survival probability. These results indicate circ‐CUX1/EWSR1/MAZ axis as a therapeutic target for aerobic glycolysis and NB progression.

MAZ promotes prostate cancer bone metastasis through transcriptionally activating the KRas-dependent RalGEFs pathway

Background

Clinically, prostate cancer (PCa) exhibits a high avidity to metastasize to bone. Myc-associated zinc-finger protein (MAZ) is a well-documented oncogene involved in the progression and metastasis of multiple cancer types, even in PCa. However, the clinical significance and biological roles of MAZ in bone metastasis of PCa remain unclear.

Methods

MAZ expression was examined in PCa tissues with bone metastasis, PCa tissues without bone metastasis and metastatic bone tissues by real-time PCR and immunohistochemistry (IHC), respectively. Statistical analysis was performed to evaluate the clinical correlation between MAZ expression and clinicopathological features and bone metastasis-free survival in PCa patients. Biological roles of MAZ in bone metastasis of PCa were investigated both in vitro by transwell assay, and in vivo by a mouse model of left cardiac ventricle inoculation. The bioinformatics analysis, western blot, pull-down assays, chromatin immunoprecipitation (ChIP) and luciferase reporter assays were applied to demonstrate and examine the relationship between MAZ and its potential downstream signalling pathway. TaqMan copy number assay was performed to identify the underlying mechanism responsible for MAZ overexpression in PCa tissues.

Results

MAZ expression is elevated in PCa tissues with bone metastasis compared with that in PCa tissues without bone metastasis, and is further increased in metastatic bone tissues. High expression of MAZ positively correlates with poor overall and bone metastasis-free survival in PCa patients. Upregulating MAZ elevates, while silencing MAZ represses the invasion and migration abilities of PCa cells in vitro and bone metastasis ability in vivo. Our results further reveal that MAZ promotes bone metastasis of PCa dependent on KRas signalling, although MAZ transcriptionally upregulates KRas and HRas expression, where the Ral guanine nucleotide exchange factor (RalGEF) signaling is responsible for the different roles of KRas and HRas in mediating the pro-bone metastasis of MAZ in PCa. Finally, our results indicate that recurrent gains contribute to MAZ overexpression in a small portion of PCa tissues.

Conclusion

These results indicate that the MAZ/Kras/ RalGEF signalling axis plays a crucial role in promoting PCa cell bone metastasis, suggesting a potential therapeutic utility of MAZ in bone metastasis of PCa.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1374-x) contains supplementary material, which is available to authorized users.

MicroRNA-125b in vascular diseases: An updated systematic review of pathogenetic implications and clinical applications

Epigenetic changes, particularly non‐coding RNAs, have been implicated extensively in the pathogenesis of vascular diseases. Specific miRNAs are involved in the differentiation, phenotypic switch, proliferation, apoptosis, cytokine production and matrix deposition of endothelial cells and/or vascular smooth muscle cells. MicroRNA‐125b has been studied in depth for its role in carcinogenesis with a double‐edged role; that is, it can act as an oncogene in some cancer types and as a tumour suppressor gene in others. However, cumulative evidence from the use of advanced miRNA profiling techniques and bioinformatics analysis suggests that miR‐125b can be a potential mediator and useful marker of vascular diseases. Currently, the exact role of miR‐125b in vascular diseases is not known. In this systematic review, we intend to provide an updated compilation of all the recent findings of miR‐125b in vascular diseases, using a systematic approach of retrieving data from all available reports followed by data summarization. MiR‐125b serves as a pathogenic player in multiple vascular pathologies involving endothelia and vascular smooth muscle cells and also serves as a diagnostic marker for vascular diseases. We further provide a computational biologic presentation of the complex network of miR‐125b and its target genes within the scope of vascular diseases.

PinX1 represses renal cancer angiogenesis via the mir-125a-3p/VEGF signaling pathway

BACKGROUND

PIN2/TRF1-interacting telomerase inhibitor 1 (PinX1) is a tumor suppressor in various tumors. However, the molecular mechanism underlying PinX1's role in cancer development and progression remains unclear. In this study, we aimed to uncover the new molecular mechanism and role of PinX1 in renal cell carcinoma (RCC) progression.

METHODS

We used miRNA microarray to detect the different expressed miRNAs upon PinX1 knockdown. Chromatin immunoprecipitation and Luciferase reporter assays were taken to identify the molecular mechanism of PinX1 in regulating mir-125-3p. In situ hybridization was performed to analyze the expression of mir-125a-3p in RCC using tissue microarray. The correlations between the mir-125a-3p expression level and clinicopathological features were evaluated using the χ² test. The role and molecular mechanism of PinX1 in RCC angiogenesis were investigated through a series of in vitro and in vivo experiments.

RESULTS

In this study, we discovered a new molecular mechanism of PinX1, in which PinX1 transcriptionally activated mir-125a-3p expression, thereby inhibiting the expression of vascular endothelial growth factor (VEGF), which is the target gene of mir-125a-3p. PinX1 also repressed tumor angiogenesis by increasing the mir-125a-3p expression in renal cancer. Moreover, the loss of mir-125a-3p expression was manifested in patients with RCC, and low miR-125a-3p levels correlated with poor survival of these patients.

CONCLUSIONS

PinX1 represses renal cancer angiogenesis through mir-125a-3p/VEGF signal pathway. The miR-125a-3p may be a candidate clinical prognostic marker and a novel therapeutic target in RCC.

Significance of liquid biopsy in glioblastoma - A review

Glioblastoma (GBM) is the most common and most aggressive primary malignant brain tumor with a 16-24 -months overall survival time (OS). Effective management is hindered by intratumoral heterogeneity, a characteristic trait of GBM which results in subpopulations of cells with altered therapeutic responsiveness, different invasiveness and growth potential. Correct initial molecular profiling of the tumor, as well as following its molecular biological changes are further impeded by the intracranial location of the tumors, hence the risks of surgical interventions. Radiological examination, the sole non-invasive method of obtaining information about the tumors, also has limitations. This review article aims to summarize the currently available information about the promising applicability of liquid biopsy, extracellular vesicles (EVs), and circulating cell-free nucleic acids (cf-NAs) in GBM patients. Liquid biopsy is a quick and inexpensive way of obtaining exceptionally relevant information about tumors, and can be performed multiple times during the clinical course of the disease. Furthermore, integrating analyses of EVs and related cf-NAs in clinical practice might also help to establish diagnosis in a non-invasive manner, and complex oncotherapy could be indicated in the future without high-risk neurosurgical interventions.

Circulating tumour DNA, microRNA and metabolites in cerebrospinal fluid as biomarkers for central nervous system malignancies

Central nervous system (CNS) malignancies can be difficult to diagnose and many do not respond satisfactorily to existing therapies. Monitoring patients with CNS malignancies for treatment response and tumour recurrence can be challenging because of the difficulty and risks of brain biopsies, and the low specificity and sensitivity of the less invasive methodologies that are currently available. Uncertainty about tumour diagnosis or whether a tumour has responded to treatment or has recurred can cause delays in therapeutic decisions that can impact patient outcome. Therefore, there is an urgent need to develop and validate reliable and minimally invasive biomarkers for CNS tumours that can be used alone or in combination with current clinical practices. Blood-based biomarkers can be informative in the diagnosis and monitoring of various types of cancer. However, blood-based biomarkers have proven suboptimal for analysis of CNS tumours. In contrast, circulating biomarkers in cerebrospinal fluid (CSF), including circulating tumour DNA, microRNAs and metabolites, hold promise for accurate and minimally invasive assessment of CNS tumours. This review summarises the current understanding of these three types of CSF biomarkers and their potential use in neuro-oncologic clinical practice.

Oxidative Stress in Mesenchymal Stem Cell Senescence: Regulation by Coding and Noncoding RNAs

SIGNIFICANCE

Mesenchymal stem cells (MSCs), adult stem cells with the potential of differentiation into mesodermal lineages, play an important role in tissue homeostasis and regeneration. In different organs, a subpopulation of MSCs is located near the vasculature and possibly represents the original source of lineage-committed mesenchymal progenitors. Recent Advances: The plasticity and immune characteristics of MSCs render them a preferential tool for regenerative cell therapy.

CRITICAL ISSUES

The culture expansion needed before MSC transplantation is associated with cellular senescence. Moreover, accelerated senescence of the total and perivascular MSC pool has been observed in humans and mouse models of premature aging disorders. MSC dysfunction is acknowledged as a culprit for the aging-associated degeneration of mesodermal tissues, but the underlying epigenetic pathways remain elusive. This article reviews current understanding of mechanisms impinging on MSC health, including oxidative stress, Nrf2-antioxidant responsive element activity, sirtuins, noncoding RNAs, and PKCs.

FUTURE DIRECTIONS

We provide evidence that epigenetic profiling of MSCs is utilitarian to the prediction of therapeutic outcomes. In addition, strategies that target oxidative stress-associated mechanisms represent promising approaches to counteract the detrimental effect of age and senescence in MSCs.-Antioxid. Redox Signal. 29, 864-879.

Aberrant miRNAs Regulate the Biological Hallmarks of Glioblastoma

GBM is the highest incidence in primary intracranial malignancy, and it remains poor prognosis even though the patient is gave standard treatment. Despite decades of intense research, the complex biology of GBM remains elusive. In view of eight hallmarks of cancer which were proposed in 2011, studies related to the eight biological capabilities in GBM have made great progress. From these studies, it can be inferred that miRs, as a mode of post-transcriptional regulation, are involved in regulating these malignant biological hallmarks of GBM. Herein, we discuss state-of-the-art research on how aberrant miRs modulate the eight hallmarks of GBM. The upregulation of 'oncomiRs' or the genetic loss of tumor suppressor miRs is associated with these eight biological capabilities acquired during GBM formation. Furthermore, we also discuss the applicable clinical potential of these research results. MiRs may aid in the diagnosis and prognosis of GBM. Moreover, miRs are also therapeutic targets of GBM. These studies will develop and improve precision medicine for GBM in the future.

MicroRNAs as biomarkers for human glioblastoma: progress and potential

Glioblastoma multiforme (GBM) is the most common malignant glioma. Despite innovative research efforts in tumor therapy, the outcome for most diagnosed patients remains poor; therefore, early diagnosis of GBM is the most effective method for achieving better patient outcomes. In recent years, combined research efforts including cellular, molecular, genetic, and bioinformatics methods have been used to investigate GBM, and the results show that variations in miRNA expression occur in GBM tissues and biological fluids. Some highly stable miRNAs circulate in the blood and cerebrospinal fluid (CSF) of both healthy individuals and diagnosed patients, thus raising the possibility that miRNAs may serve as novel diagnostic markers. In addition, increased understanding of the miRNA and mRNA interactions involved in GBM progression may lead to discovering predictive biomarkers, some of which are clinically relevant for targeted therapy and predicting prognosis. However, as this field is relatively new, some studies have yielded conflicting results. To progress in the field, different advanced techniques must be combined, including bioinformatics methods and molecular and cellular techniques. In addition, we must overcome the various challenges in non-invasive GBM biomarker detection. Here, we discuss the progress and potential of miRNAs as biomarkers for GBM and related signaling pathways. Studying the clinical relevance and applicability of these biomarkers may alter GBM patient diagnosis and treatment.

The MAZ transcription factor is a downstream target of the oncoprotein Cyr61/CCN1 and promotes pancreatic cancer cell invasion via CRAF-ERK signaling

Myc-associated zinc-finger protein (MAZ) is a transcription factor with dual roles in transcription initiation and termination. Deregulation of MAZ expression is associated with the progression of pancreatic ductal adenocarcinoma (PDAC). However, the mechanism of action of MAZ in PDAC progression is largely unknown. Here, we present evidence that MAZ mRNA expression and protein levels are increased in human PDAC cell lines, tissue samples, a subcutaneous tumor xenograft in a nude mouse model, and spontaneous cancer in the genetically engineered PDAC mouse model. We also found that MAZ is predominantly expressed in pancreatic cancer stem cells. Functional analysis indicated that MAZ depletion in PDAC cells inhibits invasive phenotypes such as the epithelial-to-mesenchymal transition, migration, invasion, and the sphere-forming ability of PDAC cells. Mechanistically, we detected no direct effects of MAZ on the expression of K-Ras mutants, but MAZ increased the activity of CRAF-ERK signaling, a downstream signaling target of K-Ras. The MAZ-induced activation of CRAF-ERK signaling was mediated via p21-activated protein kinase (PAK) and protein kinase B (AKT/PKB) signaling cascades and promoted PDAC cell invasiveness. Moreover, we found that the matricellular oncoprotein cysteine-rich angiogenic inducer 61 (Cyr61/CCN1) regulates MAZ expression via Notch-1-sonic hedgehog signaling in PDAC cells. We propose that Cyr61/CCN1-induced expression of MAZ promotes invasive phenotypes of PDAC cells not through direct K-Ras activation but instead through the activation of CRAF-ERK signaling. Collectively, these results highlight key molecular players in PDAC invasiveness and may help inform therapeutic strategies to improve clinical management and outcomes of PDAC.

MYC associated zinc finger protein promotes the invasion and metastasis of hepatocellular carcinoma by inducing epithelial mesenchymal transition

MYC associated zinc finger protein (MAZ) plays a key role in regulation of gene expression and tumor development. Studies have shown that deregulated expression of MAZ is closely related to the progression of tumors such as glioblastoma, breast cancer, prostate cancer and liposarcoma. However, the role of MAZ in hepatocellular carcinoma (HCC) has not been fully elucidated. Here, we found that expression of MAZ was increased in HCC and correlated to the distant metastasis of HCC. Moreover, we found that MAZ had a relationship with zinc finger E-box binding homeobox 1 and 2 (ZEB1 and ZEB2), two important mesenchymal markers in epithelial-mesenchymal transition (EMT) that were over-expressed in HCC. After knocking-down MAZ expression in HCC cell lines using RNA interruption, HCC cell proliferation, tumorigenesis, invasion and migration were significantly inhibited. In addition, we found that expression of other EMT markers was also changed besides ZEB1 and ZEB2 by decreasing MAZ expression, both detected in vivo and in vitro assays. Therefore, we conclude that MAZ can promote the invasion and metastasis of HCC by inducing EMT.

16p11.2 transcription factor MAZ is a dosage-sensitive regulator of genitourinary development

Genitourinary (GU) birth defects are among the most common yet least studied congenital malformations. Congenital anomalies of the kidney and urinary tract (CAKUTs) have high morbidity and mortality rates and account for ∼30% of structural birth defects. Copy number variation (CNV) mapping revealed that 16p11.2 is a hotspot for GU development. The only gene covered collectively by all of the mapped GU-patient CNVs was MYC-associated zinc finger transcription factor (MAZ), and MAZ CNV frequency is enriched in nonsyndromic GU-abnormal patients. Knockdown of MAZ in HEK293 cells results in differential expression of several WNT morphogens required for normal GU development, including Wnt11 and Wnt4. MAZ knockdown also prevents efficient transition into S phase, affects transcription of cell-cycle regulators, and abrogates growth of human embryonic kidney cells. Murine Maz is ubiquitously expressed, and a CRISPR-Cas9 mouse model of Maz deletion results in perinatal lethality with survival rates dependent on Maz copy number. Homozygous loss of Maz results in high penetrance of CAKUTs, and Maz is haploinsufficient for normal bladder development. MAZ, once thought to be a simple housekeeping gene, encodes a dosage-sensitive transcription factor that regulates urogenital development and contributes to both nonsyndromic congenital malformations of the GU tract as well as the 16p11.2 phenotype.

Engagement of circular RNA HECW2 in the nonautophagic role of ATG5 implicated in the endothelial-mesenchymal transition

Endothelial-mesenchymal transition (EndoMT) is associated with damage to blood-brain barrier (BBB) integrity. Circular RNAs (circRNAs) are highly expressed in the brain and are involved in brain diseases; however, whether circRNAs regulate the EndoMT in the brain remains unknown. Our study demonstrated that circHECW2 regulated the EndoMT by directly binding to MIR30D, a significantly downregulated miRNA from miRNA profiling, which subsequently caused an increased expression of ATG5. These findings shed new light on the understanding of the noncanonical role of ATG5 in the EndoMT induced by methamphetamine (Meth) or lipopolysaccharide (LPS). The in vivo relevance was confirmed as microinjection of circHecw2 siRNA lentivirus into the mouse hippocampus suppressed the EndoMT induced by LPS. These findings provide novel insights regarding the contribution of circHECW2 to the nonautophagic role of ATG5 in the EndoMT process in the context of drug abuse and the broad range of neuroinflammatory disorders.

The microRNA regulatory landscape of MSC-derived exosomes: a systems view

Mesenchymal stem cell (MSC)-derived exosomes mediate tissue regeneration in a variety of diseases including ischemic heart injury, liver fibrosis, and cerebrovascular disease. Despite an increasing number of studies reporting the therapeutic effects of MSC exosomes, the underlying molecular mechanisms and their miRNA complement are poorly characterized. Here we microRNA (miRNA)-profiled MSC exosomes and conducted a network analysis to identify the dominant biological processes and pathways modulated by exosomal miRNAs. At a system level, miRNA-targeted genes were enriched for (cardio)vascular and angiogenesis processes in line with observed cardiovascular regenerative effects. Targeted pathways were related to Wnt signaling, pro-fibrotic signaling via TGF-β and PDGF, proliferation, and apoptosis. When tested, MSC exosomes reduced collagen production by cardiac fibroblasts, protected cardiomyocytes from apoptosis, and increased angiogenesis in HUVECs. The intrinsic beneficial effects were further improved by virus-free enrichment of MSC exosomes with network-informed regenerative miRNAs capable of promoting angiogenesis and cardiomyocyte proliferation. The data presented here help define the miRNA landscape of MSC exosomes, establish their biological functions through network analyses at a system level, and provide a platform for modulating the overall phenotypic effects of exosomes.

MAT1 correlates with molecular subtypes and predicts poor survival in breast cancer

Objective

Menage a trois 1 (MAT1) is a targeting subunit of cyclin-dependent kinase-activating kinase and general transcription factor IIH kinase, which modulates cell cycle, transcription and DNA repair. Its dysregulation is responsible for diseases including cancers. To further explore the role of MAT1 in breast cancer, we investigated the pathways in which MAT1 might be involved, the association between MAT1 and molecular subtypes, and the role of MAT1 in clinical outcomes of breast cancer patients.

Methods

We conducted immunohistochemistry staining on tissue microarray and immunofluorescence staining on sections of MAT1 stable breast cancer cells. Also, we performed Kyoto Encyclopedia of Genes and Genomes pathway analysis, correlation analysis and prognosis analysis on public databases.

Results

MAT1 was involved in multiple pathways including normal physiology signaling and disease-related signaling. Furthermore, MAT1 positively correlated with the protein status of estrogen receptor and progesterone receptor, and was enriched in luminal-type and human epidermal growth factor receptor 2-enriched breast cancer in comparison with basal-like subtype at both mRNA and protein levels. Correlation analysis revealed significant association between MAT1 mRNA amount and epithelial markers, mesenchymal markers, cancer stem cell markers, apoptosis markers, transcription markers and oncogenes. Consistently, the results of immunofluorescence stain indicated that MAT1 overexpression enhanced the protein abundance of epidermal growth factor receptor, vimentin, sex determining region Y-box 2 and sine oculis homeobox homolog 1. Importantly, Kaplan-Meier Plotter analysis reflected that MAT1 could serve as a prognostic biomarker predicting worse relapse-free survival and metastasis-free survival.

Conclusions

MAT1 is correlated with molecular subtypes and is associated with unfavorable prognosis for breast cancer patients.

MicroRNAs in glioblastoma pathogenesis and therapy: A comprehensive review

Glioblastoma (GBM), also known as grade IV astrocytoma, is the most aggressive primary intracranial tumor of the adult brain. MicroRNAs (miRNAs), a class of small non-coding RNA species, have critical functions across various biological processes. A great deal of progress has been made recently in dissecting miRNA pathways associated with the pathogenesis of GBM. miRNA expression signatures called gene signatures also characterize and contribute to the phenotypic diversity of GBM subclasses through their ability to regulate developmental growth and differentiation. miRNA molecules have been identified as diagnostic and prognostic biomarkers for patient stratification and may also serve as therapeutic targets and agents. This review summarizes: (i) the current understanding of the roles of miRNAs in the pathogenesis of GBM, (ii) the potential use of miRNAs in GBM diagnosis and glioma grading, (iii) further prospects of developing miRNAs as novel biomarkers and therapeutic targets for GBM, and (iv) important practical considerations when considering miRNA therapy for GBM patients.

MicroRNA-30b controls endothelial cell capillary morphogenesis through regulation of transforming growth factor beta 2

The importance of microRNA (miRNA) to vascular biology is becoming increasingly evident; however, the function of a significant number of miRNA remains to be determined. In particular, the effect of growth factor regulation of miRNAs on endothelial cell morphogenesis is incomplete. Thus, we aimed to identify miRNAs regulated by pro-angiogenic vascular endothelial growth factor (VEGF) and determine the effects of VEGF-regulated miRNAs and their targets on processes important for angiogenesis. Human umbilical vein endothelial cells (HUVECs) were thus stimulated with VEGF and miRNA levels assessed using microarrays. We found that VEGF altered expression of many miRNA, and for this study focused on one of the most significantly down-regulated miRNA in HUVECs following VEGF treatment, miR-30b. Using specific miRNA mimics, we found that overexpression of miR-30b inhibited capillary morphogenesis in vitro, while depletion of endogenous miR-30b resulted in increased capillary morphogenesis indicating the potential significance of down-regulation of miR-30b as a pro-angiogenic response to VEGF stimulation. MiR-30b overexpression in HUVEC regulated transforming growth factor beta 2 (TGFβ2) production, which led to increased phosphorylation of Smad2, indicating activation of an autocrine TGFβ signaling pathway. Up-regulation of TGFβ2 by miR-30b overexpression was found to be dependent on ATF2 activation, a transcription factor known to regulate TGFβ2 expression, as miR-30b overexpressing cells exhibited increased levels of phosphorylated ATF2 and depletion of ATF2 inhibited miR-30b-induced TGFβ2 expression. However, miR-30b effects on ATF2 were indirect and found to be via targeting of the known ATF2 repressor protein JDP2 whose mRNA levels were indirectly correlated with miR-30b levels. Increased secretion of TGFβ2 from HUVEC was shown to mediate the inhibitory effects of miR-30b on capillary morphogenesis as treatment with a neutralizing antibody to TGFβ2 restored capillary morphogenesis to normal levels in miR-30b overexpressing cells. These results support that the regulation of miR-30b by VEGF in HUVEC is important for capillary morphogenesis, as increased miR-30b expression inhibits capillary morphogenesis through enhanced expression of TGFβ2.