Therapeutics targeting angiogenesis: genetics and epigenetics, extracellular miRNAs and signaling networks (Review)

Extremely low frequency-pulsed electromagnetic fields affect proangiogenic-related gene expression in retinal pigment epithelial cells

OBJECTIVES

It is known that extremely low frequency-pulsed electromagnetic fields (ELF-PEMF) influence multiple cellular and molecular processes. Retinal pigment epithelial (RPE) cells have a significant part in the emergence and pathophysiology of several ocular disorders, such as neovascularization. This study assessed the impact of ELF-PEMF on the proangiogenic features of RPE cells.

MATERIALS AND METHODS

Primary cultured RPE cells were treated with ELF-PEMF (50 Hz) for three days. Using ELISA assay, we evaluated the effects of treatment on RPE cell proliferation and apoptosis. Also, RT-PCR was used to determine the gene expression of proangiogenic factors, such as matrix metalloproteinase-2 (MMP-2), MMP-9, vascular endothelial growth factors receptor 2 (VEGFR-2), hypoxia-inducible factor 1 (HIF-1α), VEGFA, cathepsin D, connective tissue growth factor (CTGF), E2F3, tissue inhibitors of metalloproteinases 1 (TIMP-1), and TIMP-2.

RESULTS

No noticeable changes were observed in cell proliferation and cell death of ELF-PEMF-exposed RPE cells, while transcript levels of proangiogenic genes (HIF-1α, VEGFA, VEGFR-2, CTGF, cathepsin D, TIMP-1, E2F3, MMP-2, and MMP-9) increased significantly.

CONCLUSION

RPE cells are important for homeostasis of the retina. ELF-PEMF increased the gene expression of proangiogenic factors in RPE cells, which highlights concerns about the impact of this treatment on human health.

MicroRNA-regulated pathways of flow-stimulated angiogenesis and vascular remodeling in vivo

BACKGROUND

Vascular shear stress promotes endothelial cell sprouting in vitro. The impact of hemodynamic forces on microRNA (miRNA) and gene expression within growing vascular networks in vivo, however, remain poorly investigated. Arteriovenous (AV) shunts are an established model for induction of neoangiogenesis in vivo and can serve as a tool for analysis of hemodynamic effects on miRNA and gene expression profiles over time.

METHODS

AV shunts were microsurgically created in rats and explanted on postoperative days 5, 10 and 15. Neoangiogenesis was confirmed by histologic analysis and micro-computed tomography. MiRNA and gene expression profiles were determined in tissue specimens from AV shunts by microarray analysis and quantitative real-time polymerase chain reaction and compared with sham-operated veins by bioinformatics analysis. Changes in protein expression within AV shunt endothelial cells were determined by immunohistochemistry.

RESULTS

Samples from AV shunts exhibited a strong overexpression of proangiogenic cytokines, oxygenation-associated genes (HIF1A, HMOX1), and angiopoetic growth factors. Significant inverse correlations of the expressions of miR-223-3p, miR-130b-3p, miR-19b-3p, miR-449a-5p, and miR-511-3p which were up-regulated in AV shunts, and miR-27b-3p, miR-10b-5p, let-7b-5p, and let-7c-5p, which were down-regulated in AV shunts, with their predicted interacting targets C-X-C chemokine receptor 2 (CXCR2), interleukin-1 alpha (IL1A), ephrin receptor kinase 2 (EPHA2), synaptojanin-2 binding protein (SYNJ2BP), forkhead box C1 (FOXC1) were present. CXCL2 and IL1A overexpression in AV shunt endothelium was confirmed at the protein level by immunohistochemistry.

CONCLUSIONS

Our data indicate that flow-stimulated angiogenesis is determined by an upregulation of cytokines, oxygenation associated genes and miRNA-dependent regulation of FOXC1, EPHA2 and SYNJ2BP.

Targeting the Tie2-αvβ3 integrin axis with bi-specific reagents for the inhibition of angiogenesis

BACKGROUND

Increased activity of the receptor tyrosine kinase Tie2 has been implicated in the promotion of pathological angiogenesis. This activity is mainly mediated through angiopoietin (Ang)1- and Ang2-dependent activation of integrins by Tie2, rendering the Ang/Tie2/integrin axis an attractive putative target for cancer therapeutics.

RESULTS

To target this axis, we developed single domain, non-immunoglobulin high-affinity bi-specific protein inhibitors against both Tie2 and αvβ3 integrin. We have previously engineered the Ang2-binding domain of Tie2 (Ang2-BD) as a Tie2 inhibitor. Here, we engineered an exposed loop in Ang2-BD to generate variants that include an integrin-binding Arg-Gly-Asp (RGD) motif and used flow cytometry screening of a yeast-displayed Ang2-BD RGD loop library to identify the integrin antagonists. The bi-specific antagonists targeting both Tie2 and αvβ3 integrin inhibited adhesion and proliferation of endothelial cells cultured together with the αvβ3 integrin ligand vitronectin, as well as endothelial cell invasion and tube formation. The bi-specific reagents inhibited downstream signaling by Tie2 intracellularly in response to its agonist Ang1 more effectively than the wild-type Ang2 BD that binds Tie2 alone.

CONCLUSIONS

Collectively, this study-the first to describe inhibitors targeting all the known functions resulting from Tie2/integrin αvβ3 cross-talk-has created new tools for studying Tie2- and integrin αvβ3-dependent molecular pathways and provides the basis for the rational and combinatorial engineering of ligand-Tie2 and ligand-integrin αvβ3 receptor interactions. Given the roles of these pathways in cancer angiogenesis and metastasis, this proof of principle study paves the route to create novel Tie2/integrin αvβ3-targeting proteins for clinical use as imaging and therapeutic agents.

miR‑1 inhibits the progression of colon cancer by regulating the expression of vascular endothelial growth factor

MicroRNA (miR)-1 is associated with various human malignancies through repressing tumor growth, migration and angiogenesis. Recently, high-throughput transcriptional profiling confirmed that miR-1 is markedly downregulated in metastatic colorectal cancer; however, its biological functions and the specific underlying mechanisms in colorectal cancer (CRC) require further investigation. In this study, the expression of miR-1 in 111 CRC and paired normal tissue samples was measured using quantitative polymerase chain reaction analysis, and the association between miR-1 expression and clinical characteristics was evaluated. miR-1 was found to be significantly downregulated in CRC tissues compared with paired normal tissues, and in CRC cell lines compared with non-cancer cells (P<0.001), and was negatively associated with tumor size (P=0.001), differentiation (P=0.011), lymph node metastasis (P=0.001) and TNM stage (P=0.001). Further experiments revealed that miR-1 inhibited the migration and invasion of HCT116 and ClonA1 cells, and inhibited cell proliferation by affecting the cell cycle. Vascular endothelial growth factor (VEGF) was found to be a potential target of miR-1 by biological prediction, and further investigation confirmed that miR-1 significantly inhibited the expression and paracrine function of VEGF. In CRC tissues, the expression of VEGF was negatively correlated with miR-1. The low expression of miR-1 in CRC may be one of the reasons for the abnormally high expression of VEGF; the upregulation of miR-1 expression may inhibit cancer progression by downregulating VEGF. These findings indicate that treatment with miR-1 may be a novel method of tumor suppression, and provide a theoretical and experimental basis for the further targeted treatment of CRC through the regulation of miR-1 and VEGF expression.

Gene-Therapeutic Strategies Targeting Angiogenesis in Peripheral Artery Disease

The World Health Organization announced that cardiovascular disease is the number one cause of death globally, representing 31% of all global deaths. Coronary artery disease (CAD) affects approximately 5% of the US population aged 40 years and older. With an age-adjusted prevalence of approximately 12%, peripheral artery disease (PAD) affects at least 8 to 12 million Americans. Both CAD and PAD are caused by mainly atherosclerosis, the hardening and narrowing of arteries over the years by lipid deposition in the vascular bed. Despite the significant advances in interventions for revascularization and intensive medical care, patients with CAD or PAD who undergo percutaneous transluminal angioplasty have a persistent high rate of myocardial infarction, amputation, and death. Therefore, new therapeutic strategies are urgently needed for these patients. To overcome this unmet need, therapeutic angiogenesis using angiogenic growth factors has evolved in an attempt to stimulate the growth of new vasculature to compensate for tissue ischemia. After nearly 20 years of investigation, there is growing evidence of successful or unsuccessful gene therapy for ischemic heart and limb disease. This review will discuss basic and clinical data of therapeutic angiogenesis studies employing angiogenic growth factors for PAD patients and will draw conclusions on the basis of our current understanding of the biological processes of new vascularization.

Janus-Faced Myeloid-Derived Suppressor Cell Exosomes for the Good and the Bad in Cancer and Autoimmune Disease

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells originally described to hamper immune responses in chronic infections. Meanwhile, they are known to be a major obstacle in cancer immunotherapy. On the other hand, MDSC can interfere with allogeneic transplant rejection and may dampen autoreactive T cell activity. Whether MDSC-Exosomes (Exo) can cope with the dangerous and potentially therapeutic activities of MDSC is not yet fully explored. After introducing MDSC and Exo, it will be discussed, whether a blockade of MDSC-Exo could foster the efficacy of immunotherapy in cancer and mitigate tumor progression supporting activities of MDSC. It also will be outlined, whether application of native or tailored MDSC-Exo might prohibit autoimmune disease progression. These considerations are based on the steadily increasing knowledge on Exo composition, their capacity to distribute throughout the organism combined with selectivity of targeting, and the ease to tailor Exo and includes open questions that answers will facilitate optimizing protocols for a MDSC-Exo blockade in cancer as well as for strengthening their therapeutic efficacy in autoimmune disease.

Ponatinib exerts anti-angiogenic effects in the zebrafish and human umbilical vein endothelial cells via blocking VEGFR signaling pathway

Angiogenesis is a hallmark for cancer development because it is essential for cancer growth and provides the route for cancer cell migration (metastasis). Understanding the mechanism of angiogenesis and developing drugs that target the process has therefore been a major focus for research on cancer therapy. In this study, we screened 114 FDA-approved anti-cancer drugs for their effects on angiogenesis in the zebrafish. Among those with positive effects, we chose to focus on Ponatinib (AP24534; Iclusig^®) for further investigation. Ponatinib is an inhibitor of the tyrosine kinase BCR-ABL in chronic myeloid leukemia (CML), and its clinical trial has been approved by FDA for the treatment of the disease. In recent clinical trials, however, some side effects have been reported for Ponatinib, mostly on blood vessel disorders, raising the possibility that this drug may influence angiogenesis. In this study, we demonstrated that Ponatinib was able to suppress the formation of intersegmental vessels (ISV) and subintestinal vessels (SIV) in the zebrafish larvae. The anti-angiogenic effect of Ponatinib was further validated by other bioassays in human umbilical vein endothelial cells (HUVECs), including cell proliferation and migration, tube formation, and wound healing. Further experiments showed that Ponatinib inhibited VEGF-induced VEGFR2 phosphorylation and its downstream signaling pathways including Akt/eNOS/NO pathway and MAPK pathways (ERK and p38MAPK). Taken together, these results suggest that inhibition of VEGF signaling at its receptor level and downstream pathways may likely be responsible for the antiangiogenic activity of Ponatinib.

Scaffold-Based microRNA Therapies in Regenerative Medicine and Cancer

microRNA-based therapies are an advantageous strategy with applications in both regenerative medicine (RM) and cancer treatments. microRNAs (miRNAs) are an evolutionary conserved class of small RNA molecules that modulate up to one third of the human nonprotein coding genome. Thus, synthetic miRNA activators and inhibitors hold immense potential to finely balance gene expression and reestablish tissue health. Ongoing industry-sponsored clinical trials inspire a new miRNA therapeutics era, but progress largely relies on the development of safe and efficient delivery systems. The emerging application of biomaterial scaffolds for this purpose offers spatiotemporal control and circumvents biological and mechanical barriers that impede successful miRNA delivery. The nascent research in scaffold-mediated miRNA therapies translates know-how learnt from studies in antitumoral and genetic disorders as well as work on plasmid (p)DNA/siRNA delivery to expand the miRNA therapies arena. In this progress report, the state of the art methods of regulating miRNAs are reviewed. Relevant miRNA delivery vectors and scaffold systems applied to-date for RM and cancer treatment applications are discussed, as well as the challenges involved in their design. Overall, this progress report demonstrates the opportunity that exists for the application of miRNA-activated scaffolds in the future of RM and cancer treatments.

Molecular genetics and targeted therapy of WNT-related human diseases (Review)

Canonical WNT signaling through Frizzled and LRP5/6 receptors is transduced to the WNT/β-catenin and WNT/stabilization of proteins (STOP) signaling cascades to regulate cell fate and proliferation, whereas non-canonical WNT signaling through Frizzled or ROR receptors is transduced to the WNT/planar cell polarity (PCP), WNT/G protein-coupled receptor (GPCR) and WNT/receptor tyrosine kinase (RTK) signaling cascades to regulate cytoskeletal dynamics and directional cell movement. WNT/β-catenin signaling cascade crosstalks with RTK/SRK and GPCR-cAMP-PKA signaling cascades to regulate β-catenin phosphorylation and β-catenin-dependent transcription. Germline mutations in WNT signaling molecules cause hereditary colorectal cancer, bone diseases, exudative vitreoretinopathy, intellectual disability syndrome and PCP-related diseases. APC or CTNNB1 mutations in colorectal, endometrial and prostate cancers activate the WNT/β-catenin signaling cascade. RNF43, ZNRF3, RSPO2 or RSPO3 alterations in breast, colorectal, gastric, pancreatic and other cancers activate the WNT/β-catenin, WNT/STOP and other WNT signaling cascades. ROR1 upregulation in B-cell leukemia and solid tumors and ROR2 upregulation in melanoma induce invasion, metastasis and therapeutic resistance through Rho-ROCK, Rac-JNK, PI3K-AKT and YAP signaling activation. WNT signaling in cancer, stromal and immune cells dynamically orchestrate immune evasion and antitumor immunity in a cell context-dependent manner. Porcupine (PORCN), RSPO3, WNT2B, FZD5, FZD10, ROR1, tankyrase and β-catenin are targets of anti-WNT signaling therapy, and ETC-159, LGK974, OMP-18R5 (vantictumab), OMP-54F28 (ipafricept), OMP-131R10 (rosmantuzumab), PRI-724 and UC-961 (cirmtuzumab) are in clinical trials for cancer patients. Different classes of anti-WNT signaling therapeutics are necessary for the treatment of APC/CTNNB1-, RNF43/ZNRF3/RSPO2/RSPO3- and ROR1-types of human cancers. By contrast, Dickkopf-related protein 1 (DKK1), SOST and glycogen synthase kinase 3β (GSK3β) are targets of pro-WNT signaling therapy, and anti-DKK1 (BHQ880 and DKN-01) and anti-SOST (blosozumab, BPS804 and romosozumab) monoclonal antibodies are being tested in clinical trials for cancer patients and osteoporotic post-menopausal women. WNT-targeting therapeutics have also been applied as reagents for in vitro stem-cell processing in the field of regenerative medicine.

Role of exosomal proteins in cancer diagnosis

Exosomes are emerging as a new type of cancer biomarkers. Exosome is a bilayered nano-sized vesicle secreted by various living cells in all body fluids. Based on the expanding albeit incomplete knowledge of their biogenesis, secretion by cells and cancer cell-specific molecular and genetic contents, exosomes are viewed as promising, clinically-relevant surrogates of cancer progression and response to therapy. Preliminary proteomic, genetic and functional profiling of cancer cell-derived or cancer plasma-derived exosomes confirms their unique characteristics. Alterations in protein or nucleic acid profiles of exosomes in plasma correlate with pathological processes of many diseases including cancer. However, previous studies on exosome application in cancer diagnosis and treatment mainly focussed on miRNAs. With the development of rapid large-scale production, purification, extraction and screening of exosomal contents, exosomal protein application can be explored for early stage cancer diagnosis, monitoring and prognosis evaluation. Here, we summarized the recent developments in application of exosomal proteins for cancer diagnosis.

Screening and validation of differentially expressed extracellular miRNAs in acute pancreatitis

The present study aimed to screen for differentially expressed extracellular microRNAs (miRNAs) during the development of acute pancreatitis (AP) and validate the miRNA expression in the plasma of patients with AP. The culture medium of taurolithocholic acid‑3 sulfate‑treated rat pancreatic acinar AR42J cells was collected to extract total RNA for miRNA microarray analysis. Compared with the miRNA test results of the AP rats in the GEO databases, the differentially expressed extracellular miRNAs were screened. The TargetScan, miRanda, and PicTar programs were used for target gene prediction of the identified miRNAs, and gene ontology‑biological processes (GO‑BP) functional annotation was performed. Finally, the results from the combined microarray analyses (in vitro cell line and in vivo rat samples) were validated using plasma samples from patients with mild and moderately severe AP by reverse transcription‑polymerase chain reaction. The results demonstrated that extracellular miR‑24 was differentially expressed by microarray and bioinformatics analysis in both the cell line and the animal model of AP. Bioinformatics prediction analysis revealed that downstream target genes of miR‑24 included Vav2, Syk, Lhcgr, Slc9a3r1, Cacnb1, Cacna1b, Bcl10, and Fgd3. Functional enrichment analysis revealed that the main GO‑BP predicted functional presentations were positive regulation of calcium‑mediated signaling, activation of c‑Jun N‑terminal kinase activity, calcium ion transport, regulation of Rho protein signal transduction, negative regulation of the protein kinase B signaling cascade, and the T cell receptor signaling pathway. Validation analysis for the plasma miR‑24 expression in humans revealed a significant upregulation of miR‑24 in the plasma samples of AP patients compared with the healthy controls, while no significant difference was observed in the miR‑24 expression between the mild and the moderately severe AP groups. The present study confirmed the high expression of miR‑24 in peripheral blood during AP, suggesting that miR‑24 might have an intercellular communication role contributing to the AP‑associated distant organ injury.

Endostar in combination with postoperative adjuvant chemotherapy prolongs the disease free survival of stage IIIA NSCLC patients with high VEGF expression

Purpose

The aim of this study is to compare the therapeutic effect between endostar plus adjuvant chemotherapy and adjuvant chemotherapy alone in the patients with completely resected non-small cell lung cancer (NSCLC) at stage IB to IIIA.

Experimental Design

This is an open, multicenter, randomized (1:1) study with 250 NSCLC patients. Completely resected NSCLC patients at stages IB to IIIA were randomized to receive adjuvant NP plus endostar (Vinorelbine 25 mg/m² on day 1 and day 8 plus Cisplatin 75 mg/m² on day 1, and plus endostar 7.5 mg/m² per day iv for consecutive 14 days) or NP regimen alone. Every 21 days were set as one cycle for 4 cycles. The primary endpoint was disease-free survival (DFS). Secondary endpoints included tumor response rate, overall survival and safety.

Results

The two groups had no significant difference in the incidence of toxicity reaction. Endostar plus NP prolonged the DFS of patients with completely resected NSCLC at stage IIIA (19.33±3.73 vs 17.10±9.68 months) but with no statistical difference compared to NP alone. In the endostar plus NP group, those cases with high expression of vascular endothelial growth factor (VEGF) showed a significantly better DFS than those with low VEGF expression (48.45±3.52 vs 40.18±4.54 months, P<0.05).

Conclusions

Vascular targeted therapy with endostar plus NP prolongs the DFS of patients with complete resectable NSCLC in stage IIIA and significantly extends the DFS of NSCLC patients with high VEGF expression, but does not show benefits in OS for stage IB-IIIA.

Circulating Plasma Extracellular Microvesicle MicroRNA Cargo and Endothelial Dysfunction in Children with Obstructive Sleep Apnea

RATIONALE

Obese children are at increased risk for developing obstructive sleep apnea (OSA), and both of these conditions are associated with an increased risk for endothelial dysfunction (ED) in children, an early risk factor for atherosclerosis and cardiovascular disease. Although weight loss and treatment of OSA by adenotonsillectomy improve endothelial function, not every obese child or child with OSA develops ED. Exosomes are circulating extracellular vesicles containing functional mRNA and microRNA (miRNA) that can be delivered to other cells, such as endothelial cells.

OBJECTIVES

To investigate whether circulating exosomal miRNAs of children with OSA differentiate based on endothelial functional status.

METHODS

Obese children (body mass index z score >1.65) and nonobese children were recruited and underwent polysomnographic testing (PSG), and fasting endothelial function measurements and blood draws in the morning after PSG. Plasma exosomes were isolated from all subjects. Isolated exosomes were then incubated with confluent endothelial cell monolayer cultures. Electric cell-substrate impedance sensing systems were used to determine the ability of exosomes to disrupt the intercellular barrier formed by confluent endothelial cells. In addition, immunofluorescent assessments of zonula occludens-1 tight junction protein cellular distribution were conducted to examine endothelial barrier dysfunction. miRNA and mRNA arrays were also applied to exosomes and endothelial cells, and miRNA inhibitors and mimics were transfected for mechanistic assays.

MEASUREMENTS AND MAIN RESULTS

Plasma exosomes isolated from either obese children or nonobese children with OSA were primarily derived from endothelial cell sources and recapitulated ED, or its absence, in naive human endothelial cells and also in vivo when injected into mice. Microarrays identified a restricted signature of exosomal miRNAs that readily distinguished ED from normal endothelial function. Among the miRNAs, expression of exosomal miRNA-630 was reduced in children with ED and normalized after therapy along with restoration of endothelial function. Conversely, transfection of exosomes from subjects without ED with an miRNA-630 inhibitor induces the ED functional phenotype. Gene target discovery experiments further revealed that miRNA-630 regulates 416 gene targets in endothelial cells that include the Nrf2, AMP kinase, and tight junction pathways.

CONCLUSIONS

These observations elucidate a novel role of exosomal miRNA-360 as a putative key mediator of vascular function and cardiovascular disease risk in children with underlying OSA and/or obesity, and identify therapeutic targets.

ESM-1 siRNA Knockdown Decreased Migration and Expression of CXCL3 in Prostate Cancer Cells

Endothelial cell-specific molecule-1 (ESM-1), also known as endocan, is a soluble proteoglycan expressed by the vascular endothelium, which also circulates in the bloodstream. Inflammatory cytokines and proangiogenic growth factors increase its expression, and increased serum levels have been reported in several cancer types and immunocompetent patients with sepsis. The aim of this study was to analyze the expression profile of CXC-chemokines and the effects of ESM-1 gene knockdown in proliferation, migration and CXC-chemokine expression in highly metastatic human prostate PC-3 cells. Expression profiles of CXC-chemokines were analyzed in metastatic PC-3 and non-tumorigenic PWR-1E cells. siRNA-mediated knockdown of ESM-1 was performed into PC-3 cells, which were subsequently tested for cell migration and proliferation. Effect of siRNA transfection on CXC-chemokine expression was further quantified at the transcript and protein level. RT-qPCR analysis and sandwich ELISA assay revealed higher levels of ESM-1 and several CXC-chemokines in metastatic PC-3 cells compared to non-tumorigenic PWR-1E. Transfection of PC-3 cells with ESM-1-siRNA decreased cell migration with no effect on proliferation, and it was accompanied by decrease in the transcript and protein levels of the angiogenic chemokine CXCL3. We report here for the first time the ESM-1 targeting in PC-3 cells, which resulted in decreased migration, which may be related, at least in part, to decreased expression of the angiogenic CXCL3 chemokine, whose expression was found to be reduced in ESM-1-siRNA transfected cells. Additional studies are required to ascertain the biological role of ESM-1 in prostate cancer cells and the link with the expression of CXCL3.

Exosomes and their role in the micro-/macro-environment: a comprehensive review

The importance of extracellular vesicles (EVs) in cell-cell communication has long been recognized due to their ability to transfer important cellular cargoes such as DNA, mRNA, miRNAs, and proteins to target cells. Compelling evidence supports the role of EVs in the horizontal transfer of cellular material which has the potential to influence normal cellular physiology and promote various disease states. Of the different types of EVs, exosomes have garnered much attention in the past decade due to their abundance in various biological fluids and ability to affect multiple organ systems. The main focus of this review will be on cancer and how cancer-derived exosomes are important mediators of metastasis, angiogenesis, immune modulation, and the tumor macro-/microenvironment. We will also discuss exosomes as potential biomarkers for cancers due to their abundance in biological fluids, ease of uptake, and cellular content. Exosome use in diagnosis, prognosis, and in establishing treatment regimens has enormous potential to revolutionize patient care.

Angiomirs expression profiling in diffuse large B-Cell lymphoma

Despite advances in treatment, 30% of diffuse large B-cell lymphoma (DLBCL) cases are refractory or relapse after chemoimmunotherapy. Currently, the relationship between angiogenesis and angiomiRs in DLBCL is unknown. We classified 84 DLBCL cases according to stromal signatures and evaluated the expression of pro- and antiangiomiRs in paraffin embedded tissues of DLBCL and correlated them with microvascular density (MVD). 40% of cases were classified as stromal-1, 50% as stromal-2 and 10% were not classified. We observed increased expression of proangiomiRs Let-7f, miR-17, miR-18a, miR-19b, miR-126, miR-130a, miR-210, miR-296 and miR-378 in 14%, 57%, 30%, 45%, 12%, 12%, 56%, 58% and 48% of the cases, respectively. Among antiangiomiRs we found decreased expression of miR-16, miR-20b, miR-92a, miR-221 and miR-328 in, respectively, 27%, 71%, 2%, 44% and 11%. We found association between increased expression of proangiomiRs miR-126 and miR-130a and antiangiomiR miR-328 and the subtype non-GCB. We found higher levels of the antiangiomiRs miR-16, miR-221 and miR-328 in patients with low MVD and stromal-1 signature. IPI and CD34 confirmed independent impact on survival of the study group. None of the above angiomiRs showed significance as biomarker in an independent serum samples cohort of patients and controls. In conclusion, we confirmed association between antiangiomiRs miR-16, miR-221 and miR-328 and stromal-1 signature. Four angiomiRs emerged as potential therapeutic targets: proangiomiRs miR-17, miR-210 and miR-296 and antiangiomiR miR-20b. Although the four microRNAs seem to be important in DLBCL pathogenesis, they were not predictive of DLBCL onset or relapse in the serum independent cohort.

Exosomes in tumor microenvironment: novel transporters and biomarkers

Tumor microenvironment (TME) plays an integral part in the biology of cancer, participating in tumor initiation, progression, and response to therapy. Exosome is an important part of TME. Exosomes are small vesicles formed in vesicular bodies with a diameter of 30–100 nm and a classic “cup” or “dish” morphology. They can contain microRNAs, mRNAs, DNA fragments and proteins, which are shuttled from a donor cell to recipient cells. Exosomes secreted from tumor cells are called tumor-derived (TD) exosomes. There is emerging evidence that TD exosomes can construct a fertile environment to support tumor proliferation, angiogenesis, invasion and premetastatic niche preparation. TD exosomes also may facilitate tumor growth and metastasis by inhibiting immune surveillance and by increasing chemoresistance via removal of chemotherapeutic drugs. Therefore, TD-exosomes might be potential targets for therapeutic interventions via their modification or removal. For example, exosomes can serve as specific delivery vehicles to tumors of drugs, small molecules, or agents of prevention and gene therapy. Furthermore, the biomarkers detected in exosomes of biological fluids imply a potential for exosomes in the early detection and diagnosis, prediction of therapeutic efficacy, and determining prognosis of cancer. Although exosomes may serve as cancer biomarkers and aid in the treatment of cancer, we have a long way to go before we can further enhance the anti-tumor therapy of exosomes and develop exosome-based cancer diagnostic and therapeutic strategies.

Exosomes in Cancer Disease

Cancer diagnosis and therapy is steadily improving. Still, diagnosis is frequently late and diagnosis and follow-up procedures mostly are time-consuming and expensive. Searching for tumor-derived exosomes (TEX) in body fluids may provide an alternative, minimally invasive, yet highly reliable diagnostic tool. Beyond this, there is strong evidence that TEX could become a potent therapeutics. Exosomes, small vesicles delivered by many cells of the organism, are found in all body fluids. Exosomes are characterized by lipid composition, common and donor cell specific proteins, mRNA, small non-coding RNA including miRNA and DNA. Particularly the protein and miRNA markers received much attention as they may allow for highly specific diagnosis and can provide hints toward tumor aggressiveness and progression, where exosome-based diagnosis and follow-up is greatly facilitated by the recovery of exosomes in body fluids, particularly the peripheral blood. Beyond this, exosomes are the most important intercellular communicators that modulate, instruct, and reprogram their surrounding as well as distant organs. In concern about TEX this includes message transfer from tumor cells toward the tumor stroma, the premetastatic niche, the hematopoietic system and, last but not least, the instruction of non-cancer stem cells by cancer-initiating cells (CIC). Taking this into account, it becomes obvious that "tailored" exosomes offer themselves as potent therapeutic delivery system. In brief, during the last 4-5 years there is an ever-increasing, overwhelming interest in exosome research. This boom appears fully justified provided the content of the exosomes becomes most thoroughly analyzed and their mode of intercellular interaction can be unraveled in detail as this knowledge will open new doors toward cancer diagnosis and therapy including immunotherapy and CIC reprogramming.

The role of exosomes contents on genetic and epigenetic alterations of recipient cancer cells

Exosomes, as a mediator of cell-to-cell transfer of genetic information, act an important role in intercommunication between tumor cells and their niche including fibroblasts, endothelial cells, adipocytes and monocytes. Several studies have shown that tumor cells can influence their neighboring cells by releasing exosomes. These exosomes provide signaling cues for stimulation, activation, proliferation and differentiation of cells. Exosomes contain mRNAs, microRNAs (miRNA), and proteins that could be transferred to target cells inducing genetic and epigenetic changes. By facilitating the horizontal transfer of bioactive molecules such as proteins, RNAs and microRNAs, they are now thought to have vital roles in tumor invasion and metastases, inflammation, coagulation, and stem cell renewal and expansion. The aim of this review article is to discuss the significance of exosome-mediated intercellular communication within the tumor biology.

Insulin-like growth factors and their potential role in cardiac epigenetics

Cardiovascular disease (CVD) constitutes a major public health threat worldwide, accounting for 17.3 million deaths annually. Heart disease and stroke account for the majority of healthcare costs in the developed world. While much has been accomplished in understanding the pathophysiology, molecular biology and genetics underlying the diagnosis and treatment of CVD, we know less about the role of epigenetics and their molecular determinants. The impact of environmental changes and epigenetics in CVD is now emerging as critically important in understanding the origin of disease and the development of new therapeutic approaches to prevention and treatment. This review focuses on the emerging role of epigenetics mediated by insulin like-growth factors-I and -II in major CVDs such as heart failure, cardiac hypertrophy and diabetes.

miR-22-5p revealed as a potential biomarker involved in the acute phase of myocardial infarction via profiling of circulating microRNAs

Acute myocardial infarction (AMI) is a life-threatening episode of coronary artery disease. Recently, circulating myocardial-derived microRNAs (miRNAs) have been reported as potential biomarkers of infarction. The present study aimed to identify differentially expressed miRNAs in patients with ST-segment elevation myocardial infarction that could be potentially dysregulated in response to early myocardial damage. miRNA expression profile analysis was performed using the Serum/Plasma Focus miRNA Polymerase Chain Reaction (PCR) panel of Exiqon A/S (Vedbaek, Denmark) on plasma samples of patients on the first day of AMI (admission) and on samples from the identical patients collected six months following AMI. Selected miRNAs were validated by reverse transcription‑quantitative PCR (RT‑qPCR) using independent patients with AMI and a control group of patients with a stable coronary artery disease. Thirty‑two species of plasma miRNA were differentially expressed (P<0.05) on admission compared with six months following AMI. Subsequent validation in an independent patient group confirmed that miR‑133b and miR‑22‑5p were significantly up‑regulated in the serum of patients with AMI. The receiver operating characteristic (ROC) curve analysis demonstrated a diagnostic utility for miR-22-5p, which has not previously been reported to be associated with AMI. Among the selected miRNAs, miR‑22‑5p represents a novel promising biomarker for the diagnosis of AMI.

Pancreatic cancer stem cell markers and exosomes - the incentive push

Pancreatic cancer (PaCa) has the highest death rate and incidence is increasing. Poor prognosis is due to late diagnosis and early metastatic spread, which is ascribed to a minor population of so called cancer stem cells (CSC) within the mass of the primary tumor. CSC are defined by biological features, which they share with adult stem cells like longevity, rare cell division, the capacity for self renewal, differentiation, drug resistance and the requirement for a niche. CSC can also be identified by sets of markers, which for pancreatic CSC (Pa-CSC) include CD44v6, c-Met, Tspan8, alpha6beta4, CXCR4, CD133, EpCAM and claudin7. The functional relevance of CSC markers is still disputed. We hypothesize that Pa-CSC markers play a decisive role in tumor progression. This is fostered by the location in glycolipid-enriched membrane domains, which function as signaling platform and support connectivity of the individual Pa-CSC markers. Outside-in signaling supports apoptosis resistance, stem cell gene expression and tumor suppressor gene repression as well as miRNA transcription and silencing. Pa-CSC markers also contribute to motility and invasiveness. By ligand binding host cells are triggered towards creating a milieu supporting Pa-CSC maintenance. Furthermore, CSC markers contribute to the generation, loading and delivery of exosomes, whereby CSC gain the capacity for a cell-cell contact independent crosstalk with the host and neighboring non-CSC. This allows Pa-CSC exosomes (TEX) to reprogram neighboring non-CSC towards epithelial mesenchymal transition and to stimulate host cells towards preparing a niche for metastasizing tumor cells. Finally, TEX communicate with the matrix to support tumor cell motility, invasion and homing. We will discuss the possibility that CSC markers are the initial trigger for these processes and what is the special contribution of CSC-TEX.

Peptide-coated gold nanoparticles for modulation of angiogenesis in vivo

In this work, peptides designed to selectively interact with cellular receptors involved in the regulation of angiogenesis were anchored to oligo-ethylene glycol-capped gold nanoparticles (AuNPs) and used to evaluate the modulation of vascular development using an ex ovo chick chorioallantoic membrane assay. These nanoparticles alter the balance between naturally secreted pro- and antiangiogenic factors, under various biological conditions, without causing toxicity. Exposure of chorioallantoic membranes to AuNP–peptide activators of angiogenesis accelerated the formation of new arterioles when compared to scrambled peptide-coated nanoparticles. On the other hand, antiangiogenic AuNP–peptide conjugates were able to selectively inhibit angiogenesis in vivo. We demonstrated that AuNP vectorization is crucial for enhancing the effect of active peptides. Our data showed for the first time the effective control of activation or inhibition of blood vessel formation in chick embryo via AuNP-based formulations suitable for the selective modulation of angiogenesis, which is of paramount importance in applications where promotion of vascular growth is desirable (eg, wound healing) or ought to be contravened, as in cancer development.

Progress and potential of exosome analysis for early pancreatic cancer detection

INTRODUCTION

Pancreatic cancer (PaCa) is the most deadly malignancy, due to late diagnosis prohibiting surgery. Thus, strong efforts are taken improving early diagnosis via biomarkers recovered in the serum of PaCa patients.

AREAS COVERED

One promising option are PaCa-derived exosomes in patients' sera. Exosomes, small vesicles delivered by live cells and recovered in all body fluids, are a powerful diagnostic tool due to relative stability and composition covering the whole range of cancer-related biomarkers including proteins, metabolites, DNA, DNA modifications, coding and noncoding RNA. We discuss the mechanisms accounting for the condensed packaging of biomarkers, refer to studies using PaCa serum-exosomes for diagnosis. Based on an extensive literature search, we outline questions that answers may help establishing a serum-exosome-based screening for early PaCa detection. Expert commentary: Improved proteomic and genomic characterization and progress in the biogenesis of exosomes will allow for optimized and unified screening panels for PaCa diagnosis via TEX in body fluids.

FGFR inhibitors: Effects on cancer cells, tumor microenvironment and whole-body homeostasis (Review)

Fibroblast growth factor (FGF)2, FGF4, FGF7 and FGF20 are representative paracrine FGFs binding to heparan-sulfate proteoglycan and fibroblast growth factor receptors (FGFRs), whereas FGF19, FGF21 and FGF23 are endocrine FGFs binding to Klotho and FGFRs. FGFR1 is relatively frequently amplified and overexpressed in breast and lung cancer, and FGFR2 in gastric cancer. BCR-FGFR1, CNTRL-FGFR1, CUX1-FGFR1, FGFR1OP-FGFR1, MYO18A-FGFR1 and ZMYM2-FGFR1 fusions in myeloproliferative neoplasms are non-receptor-type FGFR kinases, whereas FGFR1-TACC1, FGFR2-AFF3, FGFR2-BICC1, FGFR2-PPHLN1, FGFR3-BAIAP2L1 and FGFR3-TACC3 fusions in solid tumors are transmembrane-type FGFRs with C-terminal alterations. AZD4547, BGJ398 (infigratinib), Debio-1347 and dovitinib are FGFR1/2/3 inhibitors; BLU9931 is a selective FGFR4 inhibitor; FIIN-2, JNJ-42756493, LY2874455 and ponatinib are pan-FGFR inhibitors. AZD4547, dovitinib and ponatinib are multi-kinase inhibitors targeting FGFRs, colony stimulating factor 1 receptor (CSF1R), vascular endothelial growth factor (VEGF)R2, and others. The tumor microenvironment consists of cancer cells and stromal/immune cells, such as cancer-associated fibroblasts (CAFs), endothelial cells, M2-type tumor-associating macrophages (M2-TAMs), myeloid-derived suppressor cells (MDSCs) and regulatory T cells. FGFR inhibitors elicit antitumor effects directly on cancer cells, as well as indirectly through the blockade of paracrine signaling. The dual inhibition of FGF and CSF1 or VEGF signaling is expected to enhance the antitumor effects through the targeting of immune evasion and angiogenesis in the tumor microenvironment. Combination therapy using tyrosine kinase inhibitors (FGFR or CSF1R inhibitors) and immune checkpoint blockers (anti-PD-1 or anti-CTLA-4 monoclonal antibodies) may be a promising choice for cancer patients. The inhibition of FGF19-FGFR4 signaling is associated with a risk of liver toxicity, whereas the activation of FGF23-FGFR4 signaling is associated with a risk of heart toxicity. Endocrine FGF signaling affects the pathophysiology of cancer patients who are prescribed FGFR inhibitors. Whole-genome sequencing is necessary for the detection of promoter/enhancer alterations of FGFR genes and rare alterations of other genes causing FGFR overexpression. To sustain the health care system in an aging society, a benefit-cost analysis should be performed with a focus on disease-free survival and the total medical cost before implementing genome-based precision medicine for cancer patients.

Oncological miR-182-3p, a Novel Smooth Muscle Cell Phenotype Modulator, Evidences From Model Rats and Patients

OBJECTIVE

Vascular smooth muscle cell (VSMC) phenotype change is a hallmark of vascular remodeling, which contributes to atherosclerotic diseases and can be regulated via microRNA-dependent mechanisms. We recently identified that asymmetrical dimethylarginine positively correlates to vascular remodeling-based diseases. We hypothesized that asymmetrical dimethylarginine induces smooth muscle cell (SMC) phenotypic change via a microRNA-dependent mechanism.

APPROACH AND RESULTS

Microarray analysis enabled the identification of downregulation of miR-182-3p in asymmetrical dimethylarginine-treated human aortic artery SMCs. The myeloid-associated differentiation marker (MYADM) was identified as the downstream target of miR-182-3p and implicated to contribute to miR-182-3p knockdown-mediated SMC phenotype change, which was evidenced by the increased proliferation and migration and reduced expression levels of phenotype-related genes in human aortic artery SMCs through the ERK/MAP (extracellular signal-regulated kinase/mitogen-activated protein) kinase-dependent mechanism. When inhibiting MYADM in the presence of miR-182-3p inhibitor or overexpressing MYADM in the presence of pre-miR-182-3p, human aortic artery SMCs were reversed to the differentiation phenotype. In vivo, adeno-miR-182-3p markedly suppressed carotid neointimal formation by using balloon-injured rat carotid artery model, specifically via decreased MYADM expression, whereas adeno-miR-182-3p inhibitor significantly promoted neointimal formation. Atherosclerotic lesions from patients with high asymmetrical dimethylarginine plasma levels exhibited decreased miR-182-3p expression levels and elevated MYADM expression levels.

CONCLUSIONS

miR-182-3p is a novel SMC phenotypic modulator by targeting MYADM.

Hedgehog Signaling Components Are Expressed in Choroidal Neovascularization in Laser-induced Retinal Lesion

Choroidal neovascularization is one of the major pathological changes in age-related macular degeneration, which causes devastating blindness in the elderly population. The molecular mechanism of choroidal neovascularization has been under extensive investigation, but is still an open question. We focused on sonic hedgehog signaling, which is implicated in angiogenesis in various organs. Laser-induced injuries to the mouse retina were made to cause choroidal neovascularization. We examined gene expression of sonic hedgehog, its receptors (patched1, smoothened, cell adhesion molecule down-regulated by oncogenes (Cdon) and biregional Cdon-binding protein (Boc)) and downstream transcription factors (Gli1-3) using real-time RT-PCR. At seven days after injury, mRNAs for Patched1 and Gli1 were upregulated in response to injury, but displayed no upregulation in control retinas. Immunohistochemistry revealed that Patched1 and Gli1 proteins were localized to CD31-positive endothelial cells that cluster between the wounded retina and the pigment epithelium layer. Treatment with the hedgehog signaling inhibitor cyclopamine did not significantly decrease the size of the neovascularization areas, but the hedgehog agonist purmorphamine made the areas significantly larger than those in untreated retina. These results suggest that the hedgehog-signaling cascade may be a therapeutic target for age-related macular degeneration.

Role of Alix in miRNA packaging during extracellular vesicle biogenesis

Evidence indicates that Alix, an accessory protein of the endosomal sorting complex required for transport (ESCRT), is involved in the biogenesis of extracellular vesicles (EVs). EVs contain selected patterns of microRNAs (miRNAs or miRs); however, little is known about the mechanisms of miRNA enrichment in EVs. The aim of the present study was to evaluate whether Alix is involved in the packaging of miRNAs within EVs released by human liver stem-like cells (HLSCs). EVs released from HLSCs were enriched with miRNAs and expressed Alix and several RNA-binding proteins, including Argonaute 2 (Ago2), a member of the Argonaute family known to be involved in the transport and the processing of miRNAs. Co-immunoprecipitation experiments revealed an association between Alix and Ago2. The results from RT-qPCR indicated that in the Alix/Ago2 immunoprecipitates, miRNAs were detectable. EVs were instrumental in transferring selected miRNAs from HLSCs to human endothelial cells absent in the latter cells. Alix knockdown did not influence the number of EVs released by HLSCs, but it significantly decreased miRNA expression levels in the EVs and consequently their transfer to the endothelium. Our findings indicate that Alix binds to Ago2 and miRNAs, suggesting that it plays a key role in miRNA enrichment during EV biogenesis. These results may represent a novel function of Alix, demonstrating its involvement in the EV-mediated transfer of miRNAs.

In Vitro Assays for Endothelial Cell Functions Required for Angiogenesis: Proliferation, Motility, Tubular Differentiation, and Matrix Proteolysis

This chapter deconstructs the process of angiogenesis into its component parts in order to provide simple assays to measure discrete endothelial cell functions. The techniques described will be suitable for studying stimulators and/or inhibitors of angiogenesis and determining which aspect of the process is modulated. The assays are designed to be robust and straightforward, using human umbilical vein endothelial cells, but with an option to use other sources such as microvascular endothelial cells from various tissues or lymphatic endothelial cells. It must be appreciated that such reductionist approaches cannot cover the complexity of the angiogenic process as a whole, incorporating as it does a myriad of positive and negative signals, three-dimensional interactions with host tissues and many accessory cells including fibroblasts, macrophages, pericytes and platelets. The extent to which in vitro assays predict physiological or pathological processes in vivo (e.g., wound healing, tumor angiogenesis) or surrogate techniques such as the use of Matrigel™ plugs, sponge implants, corneal assays etc remains to be determined.

Role of Growth Factors in Modulation of the Microvasculature in Adult Skeletal Muscle

Post-natal skeletal muscle is a highly plastic tissue that has the capacity to regenerate rapidly following injury, and to undergo significant modification in tissue mass (i.e. atrophy/hypertrophy) in response to global metabolic changes. These processes are reliant largely on soluble factors that directly modulate muscle regeneration and mass. However, skeletal muscle function also depends on an adequate blood supply. Thus muscle regeneration and changes in muscle mass, particularly hypertrophy, also demand rapid changes in the microvasculature. Recent evidence clearly demonstrates a critical role for soluble growth factors in the tight regulation of angiogenic expansion of the muscle microvasculature. Furthermore, exogenous modulation of these factors has the capacity to impact directly on angiogenesis and thus, indirectly, on muscle regeneration, growth and performance. This chapter reviews recent developments in understanding the role of growth factors in modulating the skeletal muscle microvasculature, and the potential therapeutic applications of exogenous angiogenic and anti-angiogenic mediators in promoting effective growth and regeneration, and ameliorating certain diseases, of skeletal muscle.

Mutation spectra of histone methyltransferases with canonical SET domains and EZH2-targeted therapy

Germline mutations in canonical SET-methyltransferases have been identified in autism and intellectual disability syndromes and gain-of-function somatic alterations in EZH2, MLL3, NSD1, WHSC1 (NSD2) and WHSC1L1 (NSD3) in cancer. EZH2 interacts with AR, ERα, β-catenin, FOXP3, NF-κB, PRC2, REST and SNAI2, resulting in context-dependent transcriptional activation and repression. Pharmacological EZH2 inhibitors are currently in clinical trials for the treatment of B-cell lymphomas and solid tumors. EZH2 inhibitors might also be applicable in the treatment of SWI/SNF-mutant cancers, reflecting the reciprocal expression of and functional overlap between EZH2 and SMARCA4. Because of the risks for autoimmune diseases, cognitive impairment, cardiomyopathy and myelodysplastic syndrome, EZH2 inhibitors should be utilized for cancer treatment in patients receiving long-term surveillance but not for cancer chemoprevention.

Dysregulated Inflammatory Signaling upon Charcot-Marie-Tooth Type 1C Mutation of SIMPLE Protein

Endosomal trafficking is a key mechanism to modulate signal propagation and cross talk. Ubiquitin adaptors, along with endosomal sorting complex required for transport (ESCRT) complexes, are also integrated to terminate ligand-receptor activation in late endosomes and multivesicular bodies (MVBs). Within these pathways, we recently demonstrated that the protein SIMPLE is a novel player in MVB regulation. SIMPLE is also clinically important and its mutation accounts for the Charcot-Marie-Tooth type 1C (CMT1C) disease. MVB defects of mutation and deletion of SIMPLE, however, are distinct. Here, we show that MVB defects found in mutation but not deletion of SIMPLE lead to impaired turnover and accumulation of ESCRT-0 protein Hrs punctain late endosomes. We further uncover increased colocalization of ubiquitin ligase TRAF6 and Hrs in late endosomes. Upon stimulation with interkeukin-1 or transforming growth factor , prolonged activation of p38 kinase/JNK is detected, while nuclear accumulation of NF-κB and phosphorylation of SMAD2 is reduced with CMT1C mutation. The aberrant kinetics we observed in inflammatory signaling may contribute to increased tumor susceptibility and changes in the levels of chemokines/cytokines that result from CMT1C mutation. We propose that altered endosomal trafficking due to malformations of MVBs and subsequent atypical signaling kinetic may account for a toxic gain of function in CMT1C pathogenesis.

Epigenetic: A missing paradigm in cellular and molecular pathways of sulfur mustard lung: a prospective and comparative study

Sulfur mustard (SM, bis- (2-chloroethyl) sulphide) is a chemical warfare agent that causes DNA alkylation, protein modification and membrane damage. SM can trigger several molecular pathways involved in inflammation and oxidative stress, which cause cell necrosis and apoptosis, and loss of cells integrity and function. Epigenetic regulation of gene expression is a growing research topic and is addressed by DNA methylation, histone modification, chromatin remodeling, and noncoding RNAs expression. It seems SM can induce the epigenetic modifications that are translated into change in gene expression. Classification of epigenetic modifications long after exposure to SM would clarify its mechanism and paves a better strategy for the treatment of SM-affected patients. In this study, we review the key aberrant epigenetic modifications that have important roles in chronic obstructive pulmonary disease (COPD) and compared with mustard lung.

Gastric cancer and gene copy number variation: emerging cancer drivers for targeted therapy

Gastric cancer (GC) is among the most common malignancy in the world with poor prognosis and limited treatment options. It has been established that gastric carcinogenesis is caused by a complex interaction between host and environmental factors. Copy number variation (CNV) refers to a form of genomic structural variation that results in abnormal gene copy numbers, including gene amplification, gain, loss and deletion. DNA CNV is an important influential factor for the expression of both protein-coding and non-coding genes, affecting the activity of various signaling pathways. CNV arises as a result of preferential selection that favors cancer development, and thus, targeting the amplified 'driver genes' in GC may provide novel opportunities for personalized therapy. The detection of CNVs in chromosomal or mitochondrial DNA from tissue or blood samples may assist the diagnosis, prognosis and targeted therapy of GC. In this review, we discuss the recent CNV discoveries that shed light on the molecular pathogenesis of GC, with a specific emphasis on CNVs that display diagnostic, prognostic or therapeutic significances in GC.

Correlation of high delta-like ligand 4 expression with peritumoral brain edema and its prediction of poor prognosis in patients with primary high-grade gliomas

OBJECT

Peritumoral brain edema (PTBE) is a common phenomenon associated with high-grade gliomas (HGGs). In this study, the authors investigated the expression of Notch delta-like ligand 4 (DLL4) and its correlation with PTBE and prognosis in patients with an HGG.

METHODS

Tumors from 99 patients with HGG were analyzed for DLL4 expression using immunohistochemistry. PTBE on preoperative MR images and the relationship between PTBE and DLL4 expression were evaluated. The effect of DLL4 on patient prognosis was assessed by using Kaplan-Meier survival and Cox proportional hazard models.

RESULTS

Immunohistochemistry results revealed that the expression of DLL4 was distributed primarily within the cytoplasm of tumor vascular endothelial cells and seldom detected in tumor cells. DLL4 expression was correlated positively with the degree of edema (r = 0.845 and p < 0.001, Spearman's test). In addition, DLL4 was an independent predictor of prognosis in patients with HGGs (p = 0.001).

CONCLUSIONS

DLL4 expression was correlated positively with the degree of PTBE and was an independent unfavorable prognostic indicator in patients with HGG.

Evaluation of Angiogenesis in Early Mycosis Fungoides Patients: Dermoscopic and Immunohistochemical Study

BACKGROUND

Angiogenesis is the production of new blood vessels from an existing vascular network; it plays a critical role in solid tumor development and metastasis.

OBJECTIVES

To assess angiogenesis in early cases of mycosis fungoides (MF) and to determine vascular patterns in MF dermoscopically.

METHODS

25 patients with MF and 20 healthy controls were included. The MF lesions were assessed dermoscopically. CD34 immunohistochemistry was performed to count dermal microvessel density (MVD).

RESULTS

The total dermal MVD was significantly higher in MF patients (19.77 ± 5.81) than in controls (4.44 ± 3.16; p = 0.013). Among them, there were 10.8 ± 4.1 sprouts of endothelial buds (clusters of cells per field) in patients and 2.4 ± 2 in controls (p = 0.000). The dotted pattern of blood vessels was the most frequently encountered pattern in the MF lesions by dermoscopy.

CONCLUSIONS

Our findings support that neoangiogenesis is significantly increased in early MF lesions and that the main dermoscopic feature of MF is dotted blood vessels.

The relevance of epigenetics to occlusive cerebral and peripheral arterial disease

Athero-thrombosis of the arteries supplying the brain and lower limb are the main causes of stroke and limb loss. New therapies are needed to improve the outcomes of athero-thrombosis. Recent evidence suggests a role for epigenetic changes in the development and progression of ischaemic injury due to atherosclerotic occlusion of peripheral arteries. DNA hypermethylation have been associated with cardiovascular diseases. Histone post-translational modifications have also been implicated in atherosclerosis. Oxidized low-density lipoprotein regulated pro-inflammatory gene expression within endothelial cells is controlled by phosphorylation/acetylation of histone H3 and acetylation of histone H4 for example. There are a number of challenges in translating the growing evidence implicating epigenetics in atherosclerosis to improved therapies for patients. These include the small therapeutic window in conditions such as acute stroke and critical limb ischaemia, since interventions introduced in such patients need to act rapidly and be safe in elderly patients with many co-morbidities. Pre-clinical animal experiments have also reported conflicting effects of some novel epigenetic drugs, which suggest that further in-depth studies are required to better understand their efficacy in resolving ischaemic injury. Effective ways of dealing with these challenges are needed before epigenetic approaches to therapy can be introduced into practice.

Buyang huanwu decoction promotes angiogenesis via vascular endothelial growth factor receptor-2 activation through the PI3K/Akt pathway in a mouse model of intracerebral hemorrhage

BACKGROUND

Intracerebral hemorrhage (ICH) is a fatal subtype of stroke that lacks effective treatments. Angiogenesis following ICH is an important response mediating brain recovery and repair. Phosphorylation of vascular endothelial growth factor receptor 2 (pVEGFR2) via PI3K/Akt signaling plays a key role in mediating cellular processes involved in repair, such as mitogenesis, angiogenesis, and vascular permeability. This study aimed to investigate the potential effects of Buyang Huanwu Decoction (BYHWD), a traditional Chinese medicine formula, on angiogenesis by VEGFR2 activation through the phosphatidylinositol 3 kinase (PI3K)/Akt signaling pathway in a mouse model of ICH.

METHODS

Adult male Kunming mice (n = 50) were randomly assigned into sham and ICH-operated groups and treated with one of the followings SU5416 (VEGFR2 inhibitor), BYHWT and BYHWT + SU5416. ICH was induced in mice by injecting collagenase (type VII) into the right globus pallidus of the mouse brain. BYHWD (4.36 g/kg) was administrated in mice by intragastric infusion. Neurological function was evaluated in mice by a modified Neurological Severity Scores (mNSS) as well as corner turn and foot-fault tests. Angiogenesis was examined by intraperitoneal injection of 5-bromodeoxyuridine (BrdU) in mice to quantify new brain vessel growth. SU5416 treatment and assessment of VEGFR2 phosphorylation as well as alterations in PI3K/Akt signaling were performed to determine whether the effect of BYHWD on angiogenesis was partly mediated by phosphorylation of VEGFR2 via the PI3K/Akt signaling pathway.

RESULTS

We show that BYHWD treated mice exhibited (i) significantly better recovery from neurological dysfunction, (ii) increased BrdU(+) nuclei in vWF(+) dilated brain vessels and (iii) higher VEGFR2 phosphorylation immunoreactivity in brain microvessels (P <0.05), (iv) higher expression of PI3K and pAkt at the protein level (P <0.05) when compared to untreated ICH mice. These beneficial effects were reversed by SU5416 (P <0.05).

CONCLUSIONS

BYHWD promoted neurological recovery and angiogenesis after ICH in mice by enhancing VEGFR2 phosphorylation through the PI3K/Akt signaling pathway.

Buyang Huanwu Decoction (BYHWD) Enhances Angiogenic Effect of Mesenchymal Stem Cell by Upregulating VEGF Expression After Focal Cerebral Ischemia

Buyang Huanwu decoction (BYHWD) has been used for centuries to treat paralysis and stroke. Previously, we have demonstrated that BYHWD combined with mesenchymal stem cell (MSC) transplantation attenuates ischemic injury partly by upregulating angiogenesis. However, the mechanisms of this drug for stroke treatment are not completely understood. Here, we aimed to clarify the mechanism of BYHWD on angiogenesis mediated by MSCs. Firstly, we verified microvessels with a size of 50-100 nm produced by either MSCs or MSCs treated by 500 μg/ml BYHWD. These exosomes were purified and found to be able to activate vascular endothelial growth factor (VEGF) expression in endothelial cells (ECs). Moreover, exosomes from MSCs and MSCs treated by BYHWD induced elevated microRNA (miRNA)-126 expression and reduced miR-221 and miR-222 expression. In MSCs, disruption of dicer, an enzyme responsible for miRNA maturation, by dicer small interfering RNA (siRNA), or RNase pretreatment abolished this ability of the exosomes. Additionally, exosomes from MSCs treated by BYHWD promoted VEGF and Ki-67 expression and augmented vascular density in rat brain after bilateral carotid artery ligation. In conclusion, our study revealed that BYHWD exposure augmented angiogenetic miRNA and VEGF expression in exosomes secreted by MSCs and elevated angiogenesis in rat brain.