Angiopoietin 2 signal complexity in cardiovascular disease and cancer

Carbohydrate antigen 125 concentrations across the ejection fraction spectrum in chronic heart failure: The EMPEROR programme

AIM

Vascular congestion may lead to an increase of carbohydrate antigen 125 (CA-125). The role of CA-125 as a biomarker of congestion or for prognosis across the full ejection fraction (EF) spectrum of chronic heart failure (HF) remains unknown.

METHODS AND RESULTS

Serum CA-125 was measured in 1111 study participants from the EMPEROR-Reduced and EMPEROR-Preserved trials. Congestive signs and symptoms were evaluated across CA-125 tertiles. Cox regression was used to study the association with outcomes. The primary outcome was a composite of first HF hospitalization or cardiovascular (CV) death. No significant association was present between baseline CA-125 levels and congestive signs or symptoms. In the overall population, higher CA-125 levels were not associated with an increased risk of primary outcome (tertile 3 vs. tertile 1: hazard ratio [HR] 1.34; 95% confidence interval [CI] 0.91-1.96; p-trend = 0.11). However, higher CA-125 levels were associated with an increased risk of primary outcome in patients with HF and reduced EF (HFrEF; tertile 3 vs. tertile 1: HR 2.25 [95% CI 1.30-3.89]), but not among patients with preserved EF (HFpEF; tertile 3 vs. tertile 1: HR 0.68 [95% CI 0.38-1.21]); interaction-p = 0.02). Patients in the upper CA-125 tertile also showed the steepest estimated glomerular filtration rate decline over time (p-trend = 0.03). The effect of empagliflozin to reduce the risk of CV death or HF hospitalization appeared to be attenuated in those with lower baseline CA-125 levels (interaction-p-trend = 0.09).

CONCLUSION

Across the range of EF in patients with chronic HF enrolled in the EMPEROR trials, the majority of whom did not have clinical evidence of congestion, CA-125 concentrations were not significantly associated with congestive signs or symptoms. CA-125 concentrations may predict HF hospitalization/CV death in patients with HFrEF, but not those with HFpEF.

CLINICAL TRIAL REGISTRATION

EMPEROR-Reduced (NCT03057977), EMPEROR-Preserved (NCT03057951).

Associations of Angiopoietin 2 and Vascular Endothelial Growth Factor-A Concentrations with Clinical End Points

BACKGROUND

Angiopoietin 2 regulates endothelial function partially mediated by vascular endothelial growth factor-A (VEGF-A) and may play a role in diabetic kidney disease (DKD). We assessed the association of angiopoietin 2 and VEGF-A with cardiorenal outcomes and investigated the effect of canagliflozin on angiopoietin 2 and VEGF-A concentrations.

METHODS

Two thousand five hundred sixty-five study participants with DKD and available plasma samples treated with canagliflozin or placebo in the Canagliflozin and Kidney Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE) trial were included. Angiopoietin 2 and VEGF-A concentrations were measured at baseline, year 1, and year 3. The primary composite end point of the trial was a composite of kidney failure, doubling of the serum creatinine level, and kidney or cardiovascular death.

RESULTS

Patients with the highest baseline quartile of angiopoietin 2, but not VEGF-A, concentration had the highest risk clinical profile. Treatment with canagliflozin significantly lowered concentrations of angiopoietin 2 (adjusted geometric mean ratio: 0.94; 95% confidence interval, 0.92 to 0.95; P < 0.001), but not VEGF-A. In multivariable-adjusted modeling, each 50% increment in log baseline angiopoietin 2 concentrations was associated with a higher risk of primary composite outcome (hazard ratio, 1.27; 95% confidence interval, 1.13 to 1.43). Angiopoietin 2 change at year 1 compared with baseline explained 10% of the effect of canagliflozin on the primary composite outcome. VEGF-A concentrations were not associated with outcomes, alone or in combination with angiopoietin 2.

CONCLUSIONS

Higher angiopoietin 2 levels were associated with cardiorenal risk among individuals with DKD independent of VEGF-A. Canagliflozin lowered angiopoietin 2 concentrations.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Evaluation of the Effects of Canagliflozin on Renal and Cardiovascular Outcomes in Participants With Diabetic Nephropathy, NCT02065791 .

Investigating the pharmacological mechanism of Zhengyuan jiaonang for treating colorectal cancer via network pharmacology analysis and experimental verification

ETHNOPHARMACOLOGICAL RELEVANCE

Zhengyuan jiaonang (ZYJN) is a traditional Chinese patent medicine (CPM) used in China for adjuvant cancer therapy, which has been proved to have anti-fatigue effects.

AIM OF STUDY

The study aims to investigate the antitumor effects of ZYJN and its underlying mechanisms using subcutaneous transplant CT26 model.

MATERIALS AND METHODS

Fingerprint analysis of ZYJN was performed using high performance liquid chromatography. The potential targets of ZYJN were predicted using bioinformatic analysis, which were further validated by Western Blot assay. Subcutaneous transplant CT26 model was used to evaluate the antitumor effects of ZYJN. The effects of ZYJN on the tumor immune microenvironment were investigated by flow cytometry. Transparent imaging was used to investigate the effects of ZYJN on fibrosis and angiogenesis.

RESULTS

ZYJN could inhibit colorectal cancer growth when administered alone or in combination with 5-FU. The combination of ZYJN and 5-FU could significantly increase the serum level of albumin (ALB) and decrease the serum level of aspartate aminotransferase (AST). In addition, the combination of ZYJN at 0.75 g/kg and 5-FU significantly decreased the serum level of vascular endothelial growth factors (VEGF) and inhibited the angiogenesis of CT26 cancer. The combination of ZYJN at 1.50 g/kg and 5-FU could promote the fibrosis process of CT26 cancer. Additionally, combination of ZYJN and 5-FU could significantly increase the percentage of tumor-infiltrating T cells and CD4+ T cells in the late stage of CT26 model, while ZYJN at 1.50 g/kg increased the percentage of NK cells as well as CD8+ T cells in the early stage of CT26 model. Western Blot analysis revealed that administration of ZYJN at 0.75 g/kg reduced the expression of PI3K-p110α, CDK1, CCNB1 and MMP-9, and inhibited the phosphorylation of Akt (Thr308).

CONCLUSIONS

ZYJN could inhibit the tumor growth of CT26 colorectal cancer by promoting tumor fibrosis, suppressing angiogenesis, migration, and invasion and modulating the tumor immune microenvironment. ZYJN enhanced the efficacy and reduced the toxicity of chemotherapy drugs in combination therapy. Our findings provide evidence for the clinical application of ZYJN in cancer treatment.

Emerging applications of anti-angiogenic nanomaterials in oncotherapy

Angiogenesis is the process of generating new blood vessels from pre-existing vasculature. Under normal conditions, this process is delicately controlled by pro-angiogenic and anti-angiogenic factors. Tumor cells can produce plentiful pro-angiogenic molecules promoting pathological angiogenesis for uncontrollable growth. Therefore, anti-angiogenic therapy, which aims to inhibit tumor angiogenesis, has become an attractive approach for oncotherapy. However, classic anti-angiogenic agents have several limitations in clinical use, such as lack of specific targeting, low bioavailability, and poor therapeutic outcomes. Hence, alternative angiogenic inhibitors are highly desired. With the emergence of nanotechnology, various nanomaterials have been designed for anti-angiogenesis purposes, offering promising features like excellent targeting capabilities, reduced side effects, and enhanced therapeutic efficacy. In this review, we describe tumor vascular features, discuss current dilemma of traditional anti-angiogenic medicines in oncotherapy, and underline the potential of nanomaterials in tumor anti-angiogenic therapy. Moreover, we discuss the current challenges of anti-angiogenic cancer treatment. We expect that this summary of anti-angiogenic nanomaterials in oncotherapy will offer valuable insights, facilitating their extensive applications in the future.

Ang-2 is a potential molecular marker for lymphatic metastasis and better response to bevacizumab therapy in ovarian cancer

PURPOSE

In ovarian cancer, there are two main routes of metastasis, namely intraperitoneal and retroperitoneal. Their biologic background is poorly understood. Identifying molecular markers involved might enable the development of tailored therapy regimens. Moreover, no reliable markers for response to anti-angiogenic treatment with bevacizumab are yet established. Angiopoietin-2 (Ang-2) is an angiogenic growth factor, involved in lymphatic activation and is associated with tumor progression. Here, we assessed the potential of Ang-2 as a molecular marker in metastasis and treatment of ovarian cancer.

METHODS

In our study, quantitative and qualitative protein Ang-2 expression in tumor tissue of ovarian cancer patients was analyzed by Western blot (n = 138) and immunohistochemistry (n = 58). Further, Ang-2 levels in blood samples were quantified in enzyme-linked immunosorbent assay (n = 38). Expression levels of different tumor spread patterns were evaluated, and survival analyses were made.

RESULTS

We observed that Ang-2 expression is significantly higher in tumors with retroperitoneal dissemination (pT1a-pT3b, pN1) compared to those showing intraperitoneal tumor growth (pT3c, pN0). In addition, patients with high Ang-2 expression have significantly longer overall survival compared to patients with low Ang-2 expression. Patients with high Ang-2 expression benefit significantly from therapy with bevacizumab.

CONCLUSION

All in all, Ang-2 may serve as a molecular marker for patients with tumors prone to spread to lymph nodes and for patients who might benefit from bevacizumab therapy.

Vascular normalization: reshaping the tumor microenvironment and augmenting antitumor immunity for ovarian cancer

Ovarian cancer remains a challenging disease with limited treatment options and poor prognosis. The tumor microenvironment (TME) plays a crucial role in tumor growth, progression, and therapy response. One characteristic feature of the TME is the abnormal tumor vasculature, which is associated with inadequate blood perfusion, hypoxia, and immune evasion. Vascular normalization, a therapeutic strategy aiming to rectify the abnormal tumor vasculature, has emerged as a promising approach to reshape the TME, enhance antitumor immunity, and synergize with immunotherapy in ovarian cancer. This review paper provides a comprehensive overview of vascular normalization and its potential implications in ovarian cancer. In this review, we summarize the intricate interplay between anti-angiogenesis and immune modulation, as well as ICI combined with anti-angiogenesis therapy in ovarian cancer. The compelling evidence discussed in this review contributes to the growing body of knowledge supporting the utilization of combination therapy as a promising treatment paradigm for ovarian cancer, paving the way for further clinical development and optimization of this therapeutic approach.

[Cardiac biomarkers and their clinical relevance]

Cardiac biomarkers are an integral, guideline-recommended part of the diagnosis and follow-up of heart diseases. High sensitivity tests for troponin I or T allow for the early diagnosis of myocardial infarction. Rule-in and rule-out algorithms based on the dynamic of plasma concentrations in the first hour after admission improve safe, evidence-based decision making for patients with acute chest pain. Low concentrations of brain natriuretic peptides (BNP or NT-proBNP) reliably exclude heart failure. Elevated BNP/NT-proBNP concentrations are part of the definition of all types of heart failure but require additional tests to diagnose heart failure. Chronic elevations of troponins and BNP/NT-proBNP identify subpopulations at increased risk of cardiovascular events even in the absence of manifest cardiac disease. Whether and how this risk can be reduced requires further evaluation. Several novel biomarkers were recently discovered and characterised. Their place in cardiovascular medicine has yet to be defined.

JUND facilitates proliferation and angiogenesis of esophageal squamous cell carcinoma cell via MAPRE2 up-regulation

OBJECTIVE

Esophageal squamous cell carcinoma (ESCC) is a globally aggressive malignant tumor. This study aimed to investigate the mechanism of JUND in ESCC development via MAPRE2.

METHODS

ESCC cells (KYSE-450 and ECA109) were transfected with small interfering RNA (si)-JUND, si-MAPRE2, si-JUND, or pcDNA3.1-MAPRE2. JUND and MAPRE2 expression in ESCC cells was detected with quantitative real-time polymerase chain reaction and western blot. Cell counting kit-8 and 5-ethynyl-2'-deoxyuridine assays were used to determine ESCC cell proliferation. Dual-luciferase reporter gene and chromatin immunoprecipitation assays were performed to assess binding between JUND and MAPRE2. Human umbilical vein endothelial cells (HUVECs) were co-cultured with ESCC cell supernatants. Angiogenesis was assessed with an in vitro angiogenesis assay. Western blot was conducted to evaluate the expression of angiogenic proteins [vascular endothelial growth factor A (VEGFA), matrix metallopeptidase 9 (MMP-9), and angiopoietin-2 (ang2)].

RESULTS

The levels of expression of JUND and MAPRE2 were high in ESCC cells. Mechanistically, JUND bound to MAPRE2 promoter and increased MAPRE2 transcription. Downregulation of JUND or MAPRE2 inhibited KYSE-450 and ECA109 cell proliferation and reduced the levels of expression of VEGFA, MMP-9, and ang2 and tube formation in HUVECs co-cultured with ESCC cell supernatants. MAPRE2 upregulation counteracted the inhibitory effects of JUND silencing on cell proliferative and angiogenic capabilities in ESCC.

CONCLUSIONS

JUND promoted MAPRE2 transcription, thereby facilitating cell proliferative and angiogenic abilities in ESCC.

Endothelial progenitor cells in the host defense response

Extensive injury of endothelial cells in blood vasculature, especially in the microcirculatory system, frequently occurs in hosts suffering from sepsis and the accompanied systemic inflammation. Pathological factors, including toxic components derived from invading microbes, oxidative stress associated with tissue ischemia/reperfusion, and vessel active mediators generated during the inflammatory response, are known to play important roles in mediating endothelial injury. Collapse of microcirculation and tissue edema developed from the failure of endothelial barrier function in vital organ systems, including the lung, brain, and kidney, are detrimental, which often predict fatal outcomes. The host body possesses a substantial capacity for maintaining vascular homeostasis and repairing endothelial damage. Bone marrow and vascular wall niches house endothelial progenitor cells (EPCs). In response to septic challenges, EPCs in their niche environment are rapidly activated for proliferation and angiogenic differentiation. In the meantime, release of EPCs from their niches into the blood stream and homing of these vascular precursors to tissue sites of injury are markedly increased. The recruited EPCs actively participate in host defense against endothelial injury and repair of damage in blood vasculature via direct differentiation into endothelial cells for re-endothelialization as well as production of vessel active mediators to exert paracrine and autocrine effects on angiogenesis/vasculogenesis. In recent years, investigations on significance of EPCs in host defense and molecular signaling mechanisms underlying regulation of the EPC response have achieved substantial progress, which promotes exploration of vascular precursor cell-based approaches for effective prevention and treatment of sepsis-induced vascular injury as well as vital organ system failure.

Assessment of Angiopoietin-2 Single Nucleotide Polymorphism in Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease that destroys joint cartilage and causes disability. Synovial inflammation, with angiogenesis, is an early event in the progression of the disease. Angiopoietin 2 (ANGPT2) is a cytokine with both inflammatory and angiogenic effects. Many genes can influence RA susceptibility and disease activity. The aim is to assess the relationship between ANGPT2 gene polymorphism (rs3020221) and RA. The study was a case-control study that included 212 RA patients and 238 age-and gender-matched healthy volunteers. RA disease activity was assessed using the Disease Activity Score 28 index. Erythrocyte sedimentation rate, C-reactive protein, rheumatoid factor, and antibody to cyclic citrullinated peptide were measured. ANGPT2 rs3020221 C > T SNP genotyping was done using real-time polymerase chain reaction (PCR). The TT genotype was more frequently represented in RA patients than in healthy controls (18.9% and 7.1%, respectively, p < 0.001) and increased the chance of developing RA four-fold, as compared to other genotypes (OR = 4.00, 95% CI = 2.09-7.63) (p < 0.001). The CT genotype was associated with elevated levels of the inflammatory markers ESR and CRP in RA patients (p = 0.012 and 0.037, respectively) as well as the DAS28 ESR Score (p < 0.001). The presence of the T allele either under the dominant model (for genotypes CT and TT) or the recessive model (for the genotype TT) predicts RA disease. Assessment of ANGPT2 gene polymorphism is useful to predict the patients with susceptibility to RA. The presence of T allele increased the risk of developing RA disease by two folds.

MYBL1 induces transcriptional activation of ANGPT2 to promote tumor angiogenesis and confer sorafenib resistance in human hepatocellular carcinoma

Angiogenesis is considered as an important process in tumor growth, metastasis of hepatocellular carcinoma (HCC) and associated with cancer progression, suggesting that an important research and development field of clinical molecular targeted drugs for HCC. However, the molecular mechanisms underlying tumor angiogenesis in HCC remains elusive. In the current study, we demonstrate that upregulation of AMYB proto-oncogene-like 1 (MYBL1) was associated with high endothelial vessel (EV) density and contributed to poor prognosis of HCC patient. Functionally, MYBL1 overexpressing enhanced the capacity of HCC cells to induce tube formation, migration of HUVECs, neovascularization in CAMs, finally, enhanced HCC cells metastasis, while silencing MYBL1 had the converse effect. Furthermore, HCC cells with high MYBL1 expression were more resistance to sorafenib treatment. We observed that CD31 staining was significantly increased in tumors formed by MYBL1-overexpressing cells but decreased in MYBL1-silenced tumors. Mechanistically, MYBL1 binds to the ANGPT2 promoter and transcriptionally upregulate ANGPT2 mRNA expression. Strikingly, treatment with monoclonal antibody against ANGPT2 significantly inhibited the growth of MYBL1-overexpressing tumors and efficiently impaired angiogenesis. Furthermore, the histone post-translational factors: protein arginine methyltransferase 5 (PRMT5), MEP50, and WDR5 were required for MYBL1-mediated ANGPT2 upregulation. Importantly, we confirmed the correlation between MYBL1 and ANGPT2 expression in a large cohort of clinical HCC samples and several published datasets in pancreatic cancer, esophageal carcinoma, stomach adenocarcinoma, and colon cancer. Our results demonstrate that MYBL1 upregulated the ANGPT2 expression, then induced angiogenesis and confer sorafenib resistance to HCC cells, and MYBL1 may represent a novel prognostic biomarker and therapeutic target for patients with HCC.

SARS-CoV-2 infection- induced growth factors play differential roles in COVID-19 pathogenesis

Aims

Biologically active molecules cytokines and growth factors (GFs) are critical regulators of tissue injury/repair and emerge as key players in COVID-19 pathophysiology. However, specific disease stage of GFs dysregulation and, whether these GFs have associations with thromboembolism and tissue injury/repair in COVID-19 remain vague.

Main methods

GF profiling in hospitalized moderate (non-ICU) and critically ill (ICU) COVID-19 patients was performed through legendPlex assay.

Key findings

Investigation revealed profound elevation of VEGF, PDGFs, EGF, TGF-α, FGF-basic, and erythropoietin (EPO) in moderate cases and decline or trend of decline with disease advancement. We found strong positive correlations of plasma VEGF, PDGFs, and EPO with endothelial dysfunction markers P-selectin and sCD40L. Interestingly, the HGF and G-CSF were upregulated at the moderate stage and remained elevated at the severe stage of COVID-19. Moreover, strong negative correlations of PDGFs (r² = 0.238, P = 0.006), EPO (r² = 0.18, P = 0.01) and EGF (r² = 0.172, P = 0.02) and positive correlation of angiopoietin-2 (r² = 0.267, P = 0.003) with D-dimer, a marker of thromboembolism, was observed. Further, plasma PDGFs (r² = 0.199, P = 0.01), EPO (r² = 0.115, P = 0.02), and EGF (r² = 0.108, P = 0.07) exhibited negative correlations with tissue injury marker, myoglobin.

Significance

Taken together, unlike cytokines, most of the assessed GFs were upregulated at the moderate stage of COVID-19. The induction of GFs likely occurs due to endothelial dysfunction and may counter the adverse effects of cytokine storms which is reflected by inverse correlations of PDGFs, EPO, and EGF with thromboembolism and tissue injury markers. The findings suggest that the assessed GFs play differential roles in the pathogenesis of COVID-19.

COL10A1 is a novel factor in the development of choroidal neovascularization

With the dramatic rise in the aging population, researching age-related macular degeneration (AMD), especially the severe form neovascular AMD (nAMD), has become more important than ever. In this study, we found that collagen type X was increased in retina-choroid tissue of mice with laser-induced choroidal neovascularization (CNV) based on immunohistofluorescence. RNA sequencing and bioinformatic analyses were performed to compare the retina-choroid tissue complex of the CNV mouse model to normal controls. Collagen type X alpha 1 chain (Col10a1) was among the most significantly upregulated genes, and the results were validated with an animal model at the mRNA and protein levels by quantitative real-time polymerase chain reaction (qPCR) and western blotting, respectively. COL10A1 was also upregulated in human retinal microvascular endothelial cells (HRMECs), human umbilical vein endothelial cells (HUVECs), RPE19 cells and RF/6A cells under hypoxic conditions. Next, in vitro and in vivo experiments were performed to study the effect of COL10A1 on neovascularization. siRNA knockdown of COL10A1 suppressed the proliferation and tube formation ability of HRMECs under hypoxic conditions. Snail family transcriptional repressor 1 (SNAIL1) and angiopoietin-2 (ANGPT2) were downregulated in COL10A1 knockdown HRMECs under hypoxic conditions and thus were potential downstream genes. Significant decreases in CNV leakage and CNV lesion area, as assessed by fundus fluorescein angiography (FFA) and immunofluorescence of choroidal flat mounts, respectively, were observed in a mouse model intravitreally injected with anti-collagen X monoclonal antibody (mAb) compared to the controls. In conclusion, COL10A1 promotes CNV formation and may represent a new candidate target for the treatment and diagnosis of nAMD and other neovascular diseases.

Longitudinal Dynamics of Coagulation and Angiogenesis Markers in Cancer Patients During and After Chemotherapy

Hemostatic parameters have been investigated as molecular determinants of tumor progression. To analyze the dynamics of microparticle-associated tissue factor activity (MPTF), tissue factor antigen (TF-Ag), and angiopоietin-2 (ANG-2) in cancer patients before, during, and after active treatment and to explore their potential as biomarkers for metastatic occurrence and death. Blood for the analysis of MPTF, TF-Ag, ANG-2, and conventional hemostatic tests was sampled in 111 patients with various cancers at 4 consecutive visits: before first chemotherapy cycle, after 3 courses, at the sixth course, and 3 months after chemotherapy cessation. Patients were followed up until metastatic progression/death or the end of the study. MPTF did not change during chemotherapy, but increased significantly after treatment cessation. Total TF-Ag and ANG-2 decreased throughout active treatment. Significant drop of their levels was observed 3 months post therapy cessation. Progressive disease was significantly associated with higher pre-chemotherapy TF-Ag and fibrinogen. Elevated baseline levels of fibrinogen were associated with increased risk of shortened progression free survival. Cessation of chemotherapy is associated with significant change of hemostatic parameters. Pre-chemotherapy levels of TF-Ag and fibrinogen may be informative of disease state and prognosis.

Targeting the Ang2/Tie2 Axis with Tanshinone IIA Elicits Vascular Normalization in Ischemic Injury and Colon Cancer

Pathological angiogenesis, as exhibited by aberrant vascular structure and function, has been well deemed to be a hallmark of cancer and various ischemic diseases. Therefore, strategies to normalize vasculature are of potential therapeutic interest in these diseases. Recently, identifying bioactive compounds from medicinal plant extracts to reverse abnormal vasculature has been gaining increasing attention. Tanshinone IIA (Tan IIA), an active component of Salvia miltiorrhiza, has been shown to play significant roles in improving blood circulation and delaying tumor progression. However, the underlying mechanisms responsible for the therapeutic effects of Tan IIA are not fully understood. Herein, we established animal models of HT-29 human colon cancer xenograft and hind limb ischemia to investigate the role of Tan IIA in regulating abnormal vasculature. Interestingly, our results demonstrated that Tan IIA could significantly promote the blood flow, alleviate the hypoxia, improve the muscle quality, and ameliorate the pathological damage after ischemic insult. Meanwhile, we also revealed that Tan IIA promoted the integrity of vascular structure, reduced vascular leakage, and attenuated the hypoxia in HT-29 tumors. Moreover, the circulating angiopoietin 2 (Ang2), which is extremely high in these two pathological states, was substantially depleted in the presence of Tan IIA. Also, the activation of Tie2 was potentiated by Tan IIA, resulting in decreased vascular permeability and elevated vascular integrity. Mechanistically, we uncovered that Tan IIA maintained vascular stability by targeting the Ang2-Tie2-AKT-MLCK cascade. Collectively, our data suggest that Tan IIA normalizes vessels in tumors and ischemic injury via regulating the Ang2/Tie2 signaling pathway.

The role of mural cells in hemorrhage of brain arteriovenous malformation

Brain arteriovenous malformation (bAVM) is the most common cause of intracranial hemorrhage (ICH), particularly in young patients. However, the exact cause of bAVM bleeding and rupture is not yet fully understood. In bAVMs, blood bypasses the entire capillary bed and directly flows from arteries to veins. The vessel walls in bAVMs have structural defects, which impair vascular integrity. Mural cells are essential structural and functional components of blood vessels and play a critical role in maintaining vascular integrity. Changes in mural cell number and coverage have been implicated in bAVMs. In this review, we discussed the roles of mural cells in bAVM pathogenesis. We focused on 1) the recent advances in human and animal studies of bAVMs; 2) the importance of mural cells in vascular integrity; 3) the regulatory signaling pathways that regulate mural cell function. More specifically, the platelet-derived growth factor-B (PDGF-B)/PDGF receptor-β (PDGFR-β), EphrinB2/EphB4, and angiopoietins/tie2 signaling pathways that regulate mural cell-recruitment during vascular remodeling were discussed in detail.

A Review on Silver Nanoparticles: Classification, Various Methods of Synthesis, and Their Potential Roles in Biomedical Applications and Water Treatment

Recent developments in nanoscience have appreciably modified how diseases are prevented, diagnosed, and treated. Metal nanoparticles, specifically silver nanoparticles (AgNPs), are widely used in bioscience. From time to time, various synthetic methods for the synthesis of AgNPs are reported, i.e., physical, chemical, and photochemical ones. However, among these, most are expensive and not eco-friendly. The physicochemical parameters such as temperature, use of a dispersing agent, surfactant, and others greatly influence the quality and quantity of the synthesized NPs and ultimately affect the material’s properties. Scientists worldwide are trying to synthesize NPs and are devising methods that are easy to apply, eco-friendly, and economical. Among such strategies is the biogenic method, where plants are used as the source of reducing and capping agents. In this review, we intend to debate different strategies of AgNP synthesis. Although, different preparation strategies are in use to synthesize AgNPs such as electron irradiation, optical device ablation, chemical reduction, organic procedures, and photochemical methods. However, biogenic processes are preferably used, as they are environment-friendly and economical. The review covers a comprehensive discussion on the biological activities of AgNPs, such as antimicrobial, anticancer anti-inflammatory, and anti-angiogenic potentials of AgNPs. The use of AgNPs in water treatment and disinfection has also been discussed in detail.

A promising field: regulating imbalance of EndMT in cardiovascular diseases

Endothelial-mesenchymal transition (EndMT) is widely involved in the occurrence and development of cardiovascular diseases. Although there is no direct evidence, it is very promising as an effective target for the treatment of these diseases. Endothelial cells need to respond to the complex cardiovascular environment through EndMT, but sustained stimuli will cause the imbalance of EndMT. Blocking the signal transduction promoting EndMT is an effective method to control the imbalance of EndMT. In particular, we also discussed the potential role of endothelial cell apoptosis and autophagy in regulating the imbalance of EndMT. In addition, promoting mesenchymal-endothelial transformation (MEndT) is also a method to control the imbalance of EndMT. However, targeting EndMT to treat cardiovascular disease still faces many challenges. By reviewing the research progress of EndMT, we have put forward some insights and translated them into challenges and opportunities for new treatment strategies for cardiovascular diseases.

The role of angiopoietin-2 and surfactant protein-D levels in SARS-CoV-2-related lung injury: A prospective, observational, cohort study

Introduction

Coronavirus disease‐2019 (COVID‐19) is a respiratory disease whose clinical manifestation ranges from asymptomatic to severe respiratory failure. The purpose of this study was to investigate the place of serum surfactant‐D (SP‐D) and angiopoetin‐2 (Ang‐2) levels in predicting severity of disease in patients diagnosed with COVID‐19.

Methods

Sixty‐four patients diagnosed with COVID‐19 between September 2020 and February 2021, 50 patients diagnosed with community‐acquired pneumonia and a 50‐member healthy control group were included in the study. Plasma samples and clinical data were collected within 72 h after admission, during hospital stay. Serum SP‐D and Ang‐2 concentrations were measured using the enzyme‐linked immunosorbent assay.

Results

SP‐D and Ang‐2 levels were significantly higher in the mild–moderate pneumonia and severe/critical patient groups compared to the asymptomatic and noncomplicated COVID‐19 patients (p < 0.001 for all groups). Serum SP‐D and Ang‐2 levels of severe‐critical COVID‐19 patients were significantly higher than CAP patients (p < 0.001). Powerful correlation was present between clinical severity of COVID‐19 and SP‐D and Ang‐2 levels (r = 0.885 p < 0.001 and r = 0.913 p < 0.001, respectively). Cut‐off values of 37.7 ng/ml (AUC = 0.763, p < 0.001, 95% confidence interval [CI] = 0.667–0.860) for SP‐D and 4208.3 pg/ml (AUC = 0.659, p = 0.004, 95% CI = 0.554–0.763) for Ang‐2 were identified as predictors of COVID‐19 disease at receiver operating characteristic curve analysis.

Conclusion

SP‐D and Ang‐2 are predictive factors in differentiating COVID‐19 patients and determining severity of disease. These data may be important for the initiation of treatment in the early stage of the disease in patients with COVID‐19.

‐

All clinicians should be aware of cutaneous lesions of COVID‐19

‐

Such manifestations could be the first presentation of the infection or an indicator of the deterioration of the patient s wellbeing.

‐

Also, such dermatologic symptoms could be because of anti‐SARS‐CoV‐2 medications, expressing the need to monitor patients cautiously.

What's new in pulmonary hypertension clinical research: lessons from the best abstracts at the 2020 American Thoracic Society International Conference

In this conference paper, we review the 2020 American Thoracic Society International Conference session titled, "What's New in Pulmonary Hypertension Clinical Research: Lessons from the Best Abstracts". This virtual mini-symposium took place on 21 October 2020, in lieu of the annual in-person ATS International Conference which was cancelled due to the COVID-19 pandemic. Seven clinical research abstracts were selected for presentation in the session, which encompassed five major themes: (1) standardizing diagnosis and management of pulmonary hypertension, (2) improving risk assessment in pulmonary arterial hypertension, (3) evaluating biomarkers of disease activity, (4) understanding metabolic dysregulation across the spectrum of pulmonary hypertension, and (5) advancing knowledge in chronic thromboembolic pulmonary hypertension. Focusing on these five thematic contexts, we review the current state of knowledge, summarize presented research abstracts, appraise their significance and limitations, and then discuss relevant future directions in pulmonary hypertension clinical research.

Epigallocatechin-3-gallate plays more predominant roles than caffeine for inducing actin-crosslinking, ubiquitin/proteasome activity and glycolysis, and suppressing angiogenesis features of human endothelial cells

A recent expression proteomics study has reported changes in cellular proteome (set of proteins) of human endothelial cells (ECs) induced by caffeine and epigallocatechin-3-gallate (EGCG), the most abundant bioactive compounds in coffee and green tea, respectively. Although both common and differential changes were highlighted by bioinformatics prediction, no experimental validation was performed. Herein, we reanalyzed these proteome datasets and performed protein-protein interactions network analysis followed by functional investigations using various assays to address the relevance of such proteome changes in human ECs functions. Protein-protein interactions network analysis revealed actin-crosslink formation, ubiquitin-proteasome activity and glycolysis as the three main networks among those significantly altered proteins induced by caffeine and EGCG. The experimental data showed predominant increases of actin-crosslink formation, ubiquitin-proteasome activity, and glycolysis (as reflected by increased F-actin and β-actin, declined ubiquitinated proteins and increased intracellular ATP, respectively) in the EGCG-treated cells. Investigations on angiogenesis features revealed that EGCG predominantly reduced ECs proliferation, migration/invasion, endothelial tube formation (as determined by numbers of nodes/junctions and meshes), barrier function (as determined by levels of VE-cadherin, zonula occludens-1 (ZO-1) and transendothelial resistance (TER)), and angiopoietin-2 secretion. However, both caffeine and EGCG had no effects on matrix metalloproteinase-2 (MMP-2) secretion. These data indicate that EGCG exhibits more potent effects on human ECs functions to induce actin-crosslink, ubiquitin-proteasome activity and glycolysis, and to suppress angiogenesis processes that commonly occur in various diseases, particularly cancers.

Use of Antiangiogenic Therapies in Pediatric Solid Tumors

Cancer is an important cause of death in childhood. In recent years, scientists have made an important effort to achieve greater precision and more personalized treatments against cancer. But since only a few pediatric patients have identifiable therapeutic targets, other ways to stop the neoplastic cell proliferation and dissemination are needed. Therefore, the inhibition of general processes involved in the growth and behavior of tumors can be a relevant strategy for the development of new cancer therapies. In the case of solid tumors, one of these processes is angiogenesis, essential for tumor growth and generation of metastases. This review summarizes the results obtained with the use of antiangiogenic drugs in the main pediatric malignant solid tumors and also an overview of clinical trials currently underway. It should be noted that due to the rarity and heterogeneity of the different types of pediatric cancer, most studies on antiangiogenic drugs include only a small number of patients or isolated clinical cases, so they are not conclusive and further studies are needed.

Angiogenesis after acute myocardial infarction

Acute myocardial infarction (MI) inflicts massive injury to the coronary microcirculation leading to vascular disintegration and capillary rarefication in the infarct region. Tissue repair after MI involves a robust angiogenic response that commences in the infarct border zone and extends into the necrotic infarct core. Technological advances in several areas have provided novel mechanistic understanding of postinfarction angiogenesis and how it may be targeted to improve heart function after MI. Cell lineage tracing studies indicate that new capillary structures arise by sprouting angiogenesis from pre-existing endothelial cells (ECs) in the infarct border zone with no meaningful contribution from non-EC sources. Single-cell RNA sequencing shows that ECs in infarcted hearts may be grouped into clusters with distinct gene expression signatures, likely reflecting functionally distinct cell populations. EC-specific multicolour lineage tracing reveals that EC subsets clonally expand after MI. Expanding EC clones may arise from tissue-resident ECs with stem cell characteristics that have been identified in multiple organs including the heart. Tissue repair after MI involves interactions among multiple cell types which occur, to a large extent, through secreted proteins and their cognate receptors. While we are only beginning to understand the full complexity of this intercellular communication, macrophage and fibroblast populations have emerged as major drivers of the angiogenic response after MI. Animal data support the view that the endogenous angiogenic response after MI can be boosted to reduce scarring and adverse left ventricular remodelling. The improved mechanistic understanding of infarct angiogenesis therefore creates multiple therapeutic opportunities. During preclinical development, all proangiogenic strategies should be tested in animal models that replicate both cardiovascular risk factor(s) and the pharmacotherapy typically prescribed to patients with acute MI. Considering that the majority of patients nowadays do well after MI, clinical translation will require careful selection of patients in need of proangiogenic therapies.

Association of Genetic Variants in ANGPT/TEK and VEGF/VEGFR with Progression and Survival in Head and Neck Squamous Cell Carcinoma Treated with Radiotherapy or Radiochemotherapy

Angiogenesis is essential for growth, progression, and metastasis of solid tumors. Vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) and angiopoietin (ANGPT)/ tyrosine kinase endothelial (TEK) signaling plays an important role in regulating angiogenesis. Very little is known about the effects of single-nucleotide polymorphisms (SNPs) in angiogenesis-related genes on treatment outcome in head and neck squamous cell carcinoma (HNSCC). Therefore, we evaluated the association between SNPs in ANGPT1, ANGPT2, TEK, VEGF, VEGFR1, and VEGFR2 genes and five clinical endpoints in 422 HNSCC patients receiving radiotherapy alone or combined with chemotherapy. Multivariate analysis showed an association of ANGPT2 rs3739391, rs3020221 and TEK rs639225 with overall survival, and VEGF rs2010963 with overall and metastasis-free survival. VEGFR2 rs1870377 and VEGF rs699947 affected local recurrence-free survival in all patients. In the combination treatment subgroup, rs699947 predicted local, nodal, and loco-regional recurrence-free survival, whereas VEGFR2 rs2071559 showed an association with nodal recurrence-free survival. However, these associations were not statistically significant after multiple testing correction. Moreover, a strong cumulative effect of SNPs was observed that survived this adjustment. These SNPs and their combinations were independent risk factors for specific endpoints. Our data suggest that certain germline variants in ANGPT2/TEK and VEGF/VEGFR2 axes may have predictive and prognostic potential in HNSCC treated with radiation or chemoradiation.

Angiopoietin-2 as a marker of endothelial activation is a good predictor factor for intensive care unit admission of COVID-19 patients

Background

Coronavirus disease-2019 (COVID-19), a respiratory disease has been associated with ischemic complications, coagulation disorders, and an endotheliitis.

Objectives

To explore endothelial damage and activation-related biomarkers in COVID-19 patients with criteria of hospitalization for referral to intensive care unit (ICU) and/or respiratory worsening.

Methods

Analysis of endothelial and angiogenic soluble markers in plasma from patients at admission.

Results

Study enrolled 40 consecutive COVID-19 patients admitted to emergency department that fulfilled criteria for hospitalization. Half of them were admitted in conventional wards without any ICU transfer during hospitalization; whereas the 20 others were directly transferred to ICU. Patients transferred in ICU were more likely to have lymphopenia, decreased SpO2 and increased D-dimer, CRP and creatinine levels. In those patients, soluble E-selectin and angiopoietin-2 were significantly increased (p value at 0.009 and 0.003, respectively). Increase in SELE gene expression (gene coding for E-selectin protein) was confirmed in an independent cohort of 32 patients using a whole blood gene expression profile analysis. In plasma, we found a strong association between angiopoetin-2 and CRP, creatinine and D-dimers (with p value at 0.001, 0.001 and 0.003, respectively). ROC curve analysis identified an Angiopoietin-2 cut-off of 5000 pg/mL as the best predictor for ICU outcome (Se = 80.1%, Sp = 70%, PPV = 72.7%, NPV = 77%), further confirmed in multivariate analysis after adjustment for creatinine, CRP or D-dimers.

Conclusion

Angiopoietin-2 is a relevant predictive factor for ICU direct admission in COVID-19 patients. This result showing an endothelial activation reinforces the hypothesis of a COVID-19-associated microvascular dysfunction.

Role of angiopoietin-2 in inflammatory autoimmune diseases: A comprehensive review

Angiogenesis is defined as the growth of new capillaries sprouting from pre-existing vasculature. Pathological angiogenesis signals can lead to dysregulated development of new vessels. Inflammation is accompanied by pathological angiogenesis. During an inflammatory process, newly formed blood vessels provide oxygen and nutrients to the inflamed tissue, facilitating the transport of inflammatory cells. Therefore, angiogenesis is closely related to pathogenesis of inflammatory autoimmune diseases. As a member of the angiopoietin family, Angiopoietin-2 (Ang-2) plays an irreplaceable role in angiogenesis. This review will narrate the expression of Ang-2 and its role in inflammatory autoimmune diseases. Collecting this information may improve the acquaintance of Ang-2 and provide a theoretical foundation for clinical trials and drug development in the future.