The Pivotal Role of the Key Angiogenic Factors in the Development of Endometrioid Pathologies of the Uterus and Ovary.

A characteristic feature of uterine pathologies is a specific change in cell metabolism, which predominantly manifests as a shift in the need for nutrients, thereby directing cells to engage in different angiogenic marker activities. Angiogenesis is one of the main signals supporting the survival and development of cells and tissues not only under physiological conditions. Therefore, it is necessary that we understand pathological hyperactivation in all uterine diseases, from endometriosis through ovarian endometrioid adenocarcinoma to malignant transformed cells of the uterine epithelium and body. This work presents the gene expression results of selected angiogenesis targets (VEGF-A, TGF-ß1, ANG1/2, and HIF-1α), cell migration, and cell-cell interaction determined in vitro. Our results suggest that angiogenesis varies in the tested pathological conditions (ectopic endometriosis-12Z; ovarian endometrioid adenocarcinoma-A2780; tumors-SK-UT-1 and RL-95-2) compared to physiological angiogenesis (HME1). The differential expression of angiogenic factors may contribute (or is a contributing factor) to the observed differences to acknowledge an inherent variability in angiogenesis among cell lines. Determining the genomic phenomena responsible for processes associated with inadequate angiogenesis in the pelvic region could help us to develop individual treatment strategies and explain resistance to treatment.

Effects of Angiogenic Factors on the Epithelial-to-Mesenchymal Transition and Their Impact on the Onset and Progression of Oral Squamous Cell Carcinoma: An Overview.

High levels of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF)-2 and angiopoietin (ANG)-2 are found in tissues from oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs). As might be expected, VEGF, FGF-2, and ANG-2 overexpression parallels the development of new blood and lymphatic vessels that nourish the growing OPMDs or OSCCs and provide the latter with metastatic routes. Notably, VEGF, FGF-2, and ANG-2 are also linked to the epithelial-to-mesenchymal transition (EMT), a trans-differentiation process that respectively promotes or exasperates the invasiveness of normal and neoplastic oral epithelial cells. Here, we have summarized published work regarding the impact that the interplay among VEGF, FGF-2, ANG-2, vessel generation, and EMT has on oral carcinogenesis. Results from the reviewed studies indicate that VEGF, FGF-2, and ANG-2 spark either protein kinase B (AKT) or mitogen-activated protein kinases (MAPK), two signaling pathways that can promote both EMT and new vessels' formation in OPMDs and OSCCs. Since EMT and vessel generation are key to the onset and progression of OSCC, as well as to its radio- and chemo-resistance, these data encourage including AKT or MAPK inhibitors and/or antiangiogenic drugs in the treatment of this malignancy.

Angiopoietins as Predictor Indexes in COVID-19 Patients in Delta and Omicron Waves.

This study aimed to explore the correlation between Angiopoietin-1 (Ang-1) and Angiopoietin-2 (Ang-2) concentrations and the Angiopoietin-2/Angiopoietin-1 ratio (Ang-2/Ang-1) with clinical outcomes, potentially serving as disease severity and survival biomarkers. A study at AHEPA University Hospital involved 90 Coronavirus Disease 2019 (COVID-19) adult patients, 30 hospitalized intensive care units (ICU), 30 inward units (non-ICU), and 30 asymptomatic non-hospitalized individuals as controls. Estimated endothelial dysfunction markers related to angiogenesis were measured. There was a statistically significant difference only between outpatient and hospitalized patients (non-ICU-ICU groups) for the Ang-1 and Ang-2 indices. The Ang-2/Ang-1 ratio has differed significantly among the individual patient groups. An ROC analysis was conducted to find an optimal threshold for distinguishing between (outpatients-non-ICU) and (non-ICU-ICU) groups. It was based on Youden's index of 0.1122 and 0.3825, respectively. The Ang-1, Ang-2 levels, and Ang-2/Ang-1 ratio were analyzed as severity indicators in COVID-19 patients. The Ang-2/Ang-1 ratio demonstrated better prognostic and diagnostic utility than individual biomarker levels. Monitoring the Ang-2/Ang-1 ratio can identify COVID-19 patients at risk and assist clinicians in tailoring treatment strategies to improve outcomes.

Angiopoietin-2 and Angiopoietin-like Proteins with a Prospective Role in Predicting Diabetic Nephropathy.

Angiopoietins are crucial growth factors for maintaining a healthy, functional endothelium. Patients with type 2 diabetes (T2D) exhibit significant levels of angiogenic markers, particularly Angiopoietin-2, which compromises endothelial integrity and is connected to symptoms of endothelial injury and failure. This report examines the levels of circulating angiopoietins in people with T2D and diabetic nephropathy (DN) and explores its link with ANGPTL proteins. We quantified circulating ANGPTL3, ANGPTL4, ANGPTL8, Ang1, and Ang2 in the fasting plasma of 117 Kuwaiti participants, of which 50 had T2D and 67 participants had DN. The Ang2 levels increased with DN (4.34 ± 0.32 ng/mL) compared with T2D (3.42 ± 0.29 ng/mL). This increase correlated with clinical parameters including the albumin-to-creatinine ratio (ACR) (r = 0.244, p = 0.047), eGFR (r = -0.282, p = 0.021), and SBP (r = -0.28, p = 0.024). Furthermore, Ang2 correlated positively to both ANGPTL4 (r = 0.541, p < 0.001) and ANGPTL8 (r = 0.41, p = 0.001). Multiple regression analysis presented elevated ANGPTL8 and ACRs as predictors for Ang2's increase in people with DN. In people with T2D, ANGPTL4 positively predicted an Ang2 increase. The area under the curve (AUC) in receiver operating characteristic (ROC) analysis of the combination of Ang2 and ANGPTL8 was 0.77 with 80.7% specificity. In conclusion, significantly elevated Ang2 in people with DN correlated with clinical markers such as the ACR, eGFR, and SBP, ANGPTL4, and ANGPTL8 levels. Collectively, this study highlights a close association between Ang2 and ANGPTL8 in a population with DN, suggesting them as DN risk predictors.

RVG29 Peptide-Modified Exosomes Loaded with Mir-133b Mediate the RhoA-ROCK Pathway to Improve Motor and Neurological Symptoms in Parkinson's Disease.

Parkinson's disease (PD) is the second most common neurodegenerative disorder worldwide. Drug delivery to the brain through the blood-brain barrier (BBB) is a significant challenge in PD treatment. Exosomes, which can efficiently traverse the BBB, which many drugs cannot penetrate, are ideal natural carriers for drug delivery. In this study, the BBB shuttle peptide was modified on the exosome surfaces. Three types of exosomes were constructed, each modified with a distinct peptide (RVG29, TAT, or Ang2) and loaded with miR-133b. The safety and brain-targeting capabilities of these peptide-modified exosomes were then evaluated. Finally, the mechanism by which RVG29-Exo-133b regulates the RhoA-ROCK signaling pathway was investigated. The findings indicate that the three peptide-modified exosomes were adequately tolerated, safe, and effectively assimilated in vivo and ex vivo, with RVG29 exhibiting superior targeting to the brain. Furthermore, RVG29-Exo-133b decreased the phosphorylation level of the Tau protein by targeting the RhoA-ROCK signaling pathway. It also enhanced the motor function in mice with PD, thereby reducing the degree of depression, improving dopaminergic neuron function, and attenuating 6-OHDA-induced nerve damage. In this study, we developed a stable drug delivery mechanism that targets the intracerebral region using exosomes. Furthermore, a novel strategy was developed to manage PD and can potentially serve as a preclinical basis for utilizing exosomes in the diagnosis and treatment of neurodegenerative conditions.

Short-term outcomes of intravitreal faricimab for refractory neovascular age-related macular degeneration.

PURPOSE: To assess the short-term outcomes of intravitreal faricimab (IVF) for previously treated refractory neovascular age-related macular degeneration (nAMD) in a real-world setting. METHODS: A retrospective monocentric study including 44 eyes treated with an upload of 4 × monthly intravitreal injections (IVI) of faricimab 6 mg/0.05 mL and followed for 4 weeks after last IVI (16 W). Patients were switched to IVF after treatment with at least three other anti-vascular endothelial growth factors (anti-VEGF). Main outcome measures included best-corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal choroidal thickness (SFCT) and retinal fluid distribution. RESULTS: 44 eyes of 44 patients with previously treated refractory nAMD (63% males) were included. Mean age was 79 ± 7 years. The total number of previous anti-VEGF before switching to IVF was 32 ± 15 IVIs/eye. BCVA (logMAR) improved significantly from 0.65 ± 0.26 to 0.50 ± 0.23 at 16 W (p < 0.01). CMT (µm) decreased significantly from 422 ± 68 to 362 ± 47 at 16 W (p < 0.01). SFCT did not change significantly at 16 W (p = 0.06). The number of eyes with subretinal fluid (SRF) decreased significantly from 29 (65%) to 13 (29%) at 16 W (p = 0.001). There were no significant changes regarding the distribution of intraretinal fluid or pigment epithelial detachment (p > 0.05). A complete fluid resolution was achieved in 8 eyes (18%). No adverse events were noticed. CONCLUSION: In the short term, IVF led to a significant decrease in CMT as well as a significant improvement of BCVA and thus appears to be an effective treatment option for previously treated refractory nAMD without relevant adverse effects.

Bispecific VEGF-A and Angiopoietin-2 Antagonist RO-101 Preclinical Efficacy in Model of Neovascular Eye Disease.

Objective: To investigate preclinical data regarding the efficacy and biocompatibility of a bispecific protein, RO-101, with effects on VEGF-A and angiopoietin-2 (Ang-2) for use in retinal diseases. Design: Experimental study. Subjects: Brown Norway rats and New Zealand White Cross rabbits. Methods: Preclinical study data of RO-101 in terms of target-specific enzyme-linked immunosorbent assay binding affinity to VEGF-A and Ang-2, vitreous half-life, inhibition of target-receptor interaction, laser choroidal neovascular membrane animal model, human umbilical vein endothelial cell migration, and biocompatibility was obtained. Where applicable, study data were compared with other anti-VEGF agents. Main Outcome Measures: Binding affinity, half-life, biocompatibility, and efficacy of RO-101. Neovascularization prevention by RO-101. Results: RO-101 demonstrated a strong binding affinity for VEGF-A and Ang-2 and in vitro was able to inhibit binding to the receptor with higher affinity than faricimab. The half-life of RO-101 is comparable to or longer than current VEGF inhibitors used in retinal disease. RO-101 was found to be biocompatible with retinal tissue in Brown Norway rats. RO-101 was as effective or more effective than current anti-VEGF therapeutics in causing regression of neovascular growth in vivo. Conclusions: RO-101 is a promising candidate for use in retinal diseases. In preclinical models, RO-101 demonstrated similar or higher regression of neovascular growth to current anti-VEGF therapeutics with comparable or longer half-life. It also demonstrates a strong binding affinity for VEGF-A and Ang-2. It also was shown to be biocompatible with retinal tissue in animal studies, indicating potential compatibility for use in humans. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

First-Year Real-Life Experience with Intravitreal Faricimab for Refractory Neovascular Age-Related Macular Degeneration.

Background: To evaluate the outcomes of intravitreal faricimab (IVF) for refractory neovascular age-related macular degeneration (nAMD) and investigate the impact of baseline optical coherence tomography, biomarkers for total IVF injections are needed. Methods: A retrospective analysis of 33 eyes of patients who completed one year (52 W) of treatment with IVF. The eyes received four IVF injections (6 mg/0.05 mL) as the upload phase. Thereafter, the treatment interval was extended to 8 or 12 weeks if disease activity was not recorded. The outcome measures included best-corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal choroidal thickness (SFCT), and retinal fluid distribution. Results: A total of 33 eyes were included. CMT decreased significantly at 52 W (p < 0.01). BCVA and SFCT did not change significantly at 52 W (p > 0.05). The number of eyes with subretinal fluid decreased significantly at 52 W (p < 0.01). Complete fluid resolution was achieved in 20 eyes (60%). The total number of injections was significantly negatively correlated with the presence of hyperreflective dots at baseline (HRDs, p < 0.01) and SFCT at baseline (p < 0.01). Conclusions: IVF led to a significant reduction in CMT with stabilization of BCVA. The total number of injections was lower in eyes with HRDs and increased SFCT at baseline. This might provide clues regarding response to IVF for future studies.

Global experience of faricimab in clinical settings - a review.

INTRODUCTION: Faricimab is a bispecific antibody that acts to reduce neoangiogenesis in exudative retinal vascular disorders. It is approved for use in neovascular age-related macular degeneration and diabetic macular edema. We review the published efficacy and safety of faricimab in clinical settings. AREAS COVERED: A comprehensive literature review was conducted. Based on the 14 published real-world studies, 1127 patients (1204 eyes) were treated with faricimab. The majority of studies (14) included pre-treated patients. Most studies (13) showed central macular thickness improvement. However visual acuity improved in only half of the studies analyzed. Four studies demonstrated an extension of the treatment. Only 4 eyes (0.33%) reported intraocular inflammation and 3 eyes (0.24%) reported retinal pigment epithelial tear. EXPERT OPINION: The clinical experience with faricimab to date has the potential to provide a stable visual outcome with reduced treatment burden in cases that are resistant to other approved anti-VEGF agents. There are no major safety concerns based on this data analysis.

Pharmacological inhibition of the ACE/Ang-2/AT1 axis alleviates mechanical ventilation-induced pulmonary fibrosis.

Mechanical ventilation (MV) is an essential therapy for acute respiratory distress syndrome (ARDS) and pulmonary fibrosis. However, it can also induce mechanical ventilation-induced pulmonary fibrosis (MVPF) and the underlying mechanism remains unknown. Based on a mouse model of MVPF, the present study aimed to explore the role of the angiotensin-converting enzyme/angiotensin II/angiotensin type 1 receptor (ACE/Ang-2/AT1R) axis in the process of MVPF. In addition, recombinant angiotensin-converting enzyme 2(rACE2), AT1R inhibitor valsartan, AGTR1-directed shRNA and ACE inhibitor perindopril were applied to verify the effect of inhibiting ACE/Ang-2/AT1R axis in the treatment of MVPF. Our study found MV induced an inflammatory reaction and collagen deposition in mouse lung tissue accompanied by the activation of ACE in lung tissue, increased concentration of Ang-2 in bronchoalveolar lavage fluid (BALF), and upregulation of AT1R in alveolar epithelial cells. The process of pulmonary fibrosis could be alleviated by the application of the ACE inhibitor perindopril, ATIR inhibitor valsartan and AGTR1-directed shRNA. Meanwhile, rACE2 could also alleviate MVPF through the degradation of Ang-2. Our finding indicated the ACE/Ang-2/AT1R axis played an essential role in the pathogenesis of MVPF. Pharmacological inhibition of the ACE/Ang-2/AT1R axis might be a promising strategy for the treatment of MVPF.

Real-World Data on Faricimab Switching in Treatment-Refractory Neovascular Age-Related Macular Degeneration.

Faricimab is a newly approved bispecific antibody for neovascular age-related macular degeneration (nAMD). Our study aims to evaluate clinical outcomes of faricimab switching in patients with treatment-refractory nAMD; determine parameters that predict these outcomes; and obtain patient subjective experience on this new injection. This is a retrospective case review with clinical and imaging data from a tertiary referral unit (Birmingham and Midland Eye Centre, UK), involving patients who were switched to faricimab between 1 January and 1 December 2023. In all, 63 eyes (54 patients) with a mean age of 79.2 ± 7.8 and mean of 41.5 ± 22.4 previous anti-VEGF injections were analysed. With a mean of 4.81 ± 1.16 faricimab injections over 6.98 ± 1.75 months, post-treatment visual acuity was logMAR 0.49 ± 0.36 and central macular thickness (CMT) was 320.3 ± 97.9 µm. After first dose, 39.1% achieved complete dryness and 89.1% had anatomical improvement. Presence of subretinal fluid was a predictor of better functional outcomes (p = 0.001, ß = -0.182), while initial CMT predicted better anatomical outcomes (p = 0.001, ß = 0.688). Compared to their experiences of previous anti-VEGF injections, 89% of patients reported no more discomfort and 87.0% experienced no more floaters, photopsia, or bubbles post-injection. Faricimab switching has anatomical efficacy but limited functional improvement in treatment-refractory AMD. Patient experiences of faricimab compared to previous injections were overall positive.

MiR-221-5p regulates blood-brain barrier dysfunction through the angiopoietin-1/-2/Tie-2 signaling axis after subarachnoid hemorrhage.

AIM: To explore the potential role of microRNA miR-221-5p on the angiopoietin-1 (Ang-1)/Ang-2/Tie-2 signaling axis after subarachnoid hemorrhage (SAH) in a rat model. METHODS: Aspects of the rat's behavior were measured using the Kaoutzanis scoring system to test neurological responses. This included feeding behavior, body contraction, motor, and eye-opening responses. Brain sections were studied using transmission electron microscopy and Evans blue extravasation. Levels of Ang-1, Ang-2, and Tie-2 were determined by Western blot, while miR-221-5p was quantified using stem-loop real-time quantitative PCR (RT-qPCR). RESULTS: The SAH group responded worse to the neurological response test than the sham-operated group. The intercellular space was widened in the SAH group, but not in the sham-operated group. Evans blue dye leaked significantly more into brain tissue cells of the SAH group. Stem-loop qRT-PCR showed elevated miR-221-5p levels. Additionally, Ang-1 and Tie-2 were reduced but Ang-2 expression was increased after SAH. This led to a significant reduction of the Ang-1/Ang-2 ratio in the brain tissue, which was associated with the destruction of the blood-brain barrier. CONCLUSION: The data indicate that miR-221-5p might regulate blood-brain barrier dysfunction through the Ang-1/Ang-2/Tie-2 signaling axis, suggesting that it should be further investigated as a potential novel biomarker.

Preoperative Serum Levels of PDGF-AB, PDGF-BB, TGF-α, EGF and ANG-2 in the Diagnosis of Endometrial Cancer.

(1) Background: It is relevant to find new diagnostic biomarkers for endometrial cancer. This study aimed to investigate whether PDGF-AB, PDGF-BB, TGF-α, EGF and ANG-2 could be considered new useful markers for diagnosis and survival of endometrial cancer. (2) Methods: A total of 93 women diagnosed with endometrial cancer (EC) and 66 patients with non-cancerous endometrial lesions (NCEL) were included in this study. (3) Results: Median serum levels of PDGF-AB, PDGF-BB, TGF-α, EGF and ANG-2 were significantly higher in the EC group compared to the NCEL group (for PDGF-AB, PDGF-BB, TGF-α and ANG-2, p = 0.0000; for EGF, p = 0.0186). The cut-off level of PDGF-AB was set at 127.69 pg/mL with a sensitivity of 87.1% and a specificity of 66.67% (AUC = 0.78, p < 0.000001). The cut-off level of PDGF-BB was set at 207.86 ng/L with a sensitivity of 82.8% and a specificity of 75.76% (AUC = 0.85, p < 0.000001). The cut-off level of TGF-α was set at 33.85 ng/L with a sensitivity of 82.8% and a specificity of 75.76% (AUC = 0.82, p < 0.000001). The cut-off level of EGF was set at 934.76 pg/mL with a sensitivity of 83.87% and a specificity of 28.79% (AUC = 0.61, p = 0.018472). The cut-off level of ANG-2 was set at 3120.68 pg/mL with a sensitivity of 72.04% and a specificity of 93.94% (AUC = 0.87, p < 0.000001). (4) Conlusion: It was concluded that all the proteins studied could be potential diagnostic markers in endometrial cancer.

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.

MDMB-FUBINACA Influences Brain Angiogenesis and the Expression of VEGF, ANG-1, and ANG-2.

AIM: This study aims to explore the impact of the synthetic cannabinoid methyl 2-(1-(4- fluorobenzyl)-1H-indazole-3-carboxamido)-3,3-dimethylbutanoate (MDMB-FUBINACA) on the angiogenesis process in human brain microvascular endothelial cells. BACKGROUND: Synthetic cannabinoids (SCs) are substances that mimic the natural components found in the cannabis plant. SCs are considered prohibited substances that have a clear impact on the central nervous system (CNS). OBJECTIVES: The purpose of this study is to explore how MDMB-FUBINACA influences angiogenesis in human brain microvascular endothelial cells and to clarify the pathways related to the cannabinoid receptors. METHODS: Human brain microvascular endothelial cells (hBMECs) were grown in the medium containing Dulbecco Modified Eagle Medium (DMEM/F12) using an endothelial cell growth kit. Endothelial cell viability was evaluated using the MTT test. Migration ability was measured using the Wound healing test. The angiogenic capability was measured using a Tube Formation assay. Real-time polymerase chain reaction (RT-PCR) was utilized to explore the mRNA concentrations following MDMBFUBINACA treatment. ELISA and Western blotting were also employed to measure the protein levels. RESULTS: MDMB-FUBINACA greatly increases tube formation, endothelial cell proliferation, and migration. Pro-angiogenic factors such as angiopoietins 1 and 2 (ANG-1 and 2) and vascular endothelial growth factor (VEGF) were shown to be increased at both the RNA and protein levels. CONCLUSION: MDMB-FUBINACA induces the progression of the angiogenesis process by inducing the expression of pro-angiogenic factors. These findings aim toward developing novel treatments for angiogenesis- related disorders.

miR-221-3p targets Ang-2 to inhibit the transformation of HCMECs to tip cells.

Postembryonic angiogenesis is mainly induced by various proangiogenic factors derived from the original vascular network. Previous studies have shown that the role of Ang-2 in angiogenesis is controversial. Tip cells play a vanguard role in angiogenesis and exhibit a transdifferentiated phenotype under the action of angiogenic factors. However, whether Ang-2 promotes the transformation of endothelial cells to tip cells remains unknown. Our study found that miR-221-3p was highly expressed in HCMECs cultured for 4 h under hypoxic conditions (1% O2 ). Moreover, miR-221-3p overexpression inhibited HCMECs proliferation and tube formation, which may play an important role in hypoxia-induced angiogenesis. By target gene prediction, we further demonstrated that Ang-2 was a downstream target of miR-221-3p and miR-221-3p overexpression inhibited Ang-2 expression in HCMECs under hypoxic conditions. Subsequently, qRT-PCR and western blotting methods were performed to analyse the role of miR-221-3p and Ang-2 on the regulation of tip cell marker genes. MiR-221-3p overexpression inhibited CD34, IGF1R, IGF-2 and VEGFR2 proteins expression while Ang-2 overexpression induced CD34, IGF1R, IGF-2 and VEGFR2 expression in HCMECs under hypoxic conditions. In addition, we further confirmed that Ang-2 played a dominant role in miR-221-3p inhibitors promoting the transformation of HCMECs to tip cells by using Ang-2 shRNA to interfere with miR-221-3p inhibitor-treated HCMECs under hypoxic conditions. Finally, we found that miR-221-3p expression was significantly elevated in both serum and myocardial tissue of AMI rats. Hence, our data showed that miR-221-3p may inhibit angiogenesis after acute myocardial infarction by targeting Ang-2 to inhibit the transformation of HCMECs to tip cells.

Preclinical evaluation of the VEGF/Ang2 bispecific nanobody BI 836880 in nasopharyngeal carcinoma models.

Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC) is endemic to parts of Asia and overexpression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α are common in NPC. Anti-vascular agents have known clinical activity in patients with recurrent/ metastatic NPC and in this study, we investigated the anti-tumor effect of BI 836880, a humanized bispecific nanobody against VEGF and angiopoietin-2 (Ang2), in preclinical models of EBV-positive and EBV-negative NPC. The efficacy of BI 836880 was also compared with bevacizumab, a recombinant humanized monoclonal antibody against VEGF. We found that BI 836880 could exert growth-inhibitory effect on endothelial cells (HUVEC-C) and the EBV-negative NPC cell line (HK1), but to a lesser extent in the EBV-positive NPC cell lines, C17C and C666-1. In patients-derived xenograft (PDX) models of NPC - Xeno-2117 and Xeno-666, BI 836880 could suppress tumor growth and Ki67, as well as induce tumor necrosis and reduce microvessel density. Moreover, treatment with BI 836880 increased the level of macrophage infiltration in both PDX tumor models of NPC, suggesting that BI 836880 may exert immunomodulatory effect on the NPC immune microenvironment. When compared with bevacizumab, BI 836880 appeared to show at least comparable activity as bevacizumab in terms of its anti-proliferative and anti-angiogenic effects. This study showed that BI 836880 has anti-proliferative, anti-angiogenic and possibly immunomodulatory effect in clinical models of NPC, therefore the dual targeting of VEGF and Ang2 signaling in NPC should be further investigated.

KRAS mutation-driven angiopoietin 2 bestows anti-VEGF resistance in epithelial carcinomas.

Defining reliable surrogate markers and overcoming drug resistance are the most challenging issues for improving therapeutic outcomes of antiangiogenic drugs (AADs) in cancer patients. At the time of this writing, no biomarkers are clinically available to predict AAD therapeutic benefits and drug resistance. Here, we uncovered a unique mechanism of AAD resistance in epithelial carcinomas with KRAS mutations that targeted angiopoietin 2 (ANG2) to circumvent antivascular endothelial growth factor (anti-VEGF) responses. Mechanistically, KRAS mutations up-regulated the FOXC2 transcription factor that directly elevated ANG2 expression at the transcriptional level. ANG2 bestowed anti-VEGF resistance as an alternative pathway to augment VEGF-independent tumor angiogenesis. Most colorectal and pancreatic cancers with KRAS mutations were intrinsically resistant to monotherapies of anti-VEGF or anti-ANG2 drugs. However, combination therapy with anti-VEGF and anti-ANG2 drugs produced synergistic and potent anticancer effects in KRAS-mutated cancers. Together, these data demonstrate that KRAS mutations in tumors serve as a predictive marker for anti-VEGF resistance and are susceptible to combination therapy with anti-VEGF and anti-ANG2 drugs.

Angiopoietin-2 expression and its relationship with lymphangiogenesis and clinicopathological characteristics in cutaneous malignant melanoma.

Objective: The aim of this study was to investigate angiopoietin-2 (Ang-2/ANGPT2) expression and its relationship with lymphangiogenesis and clinicopathological characteristics in cutaneous malignant melanoma (CMM). Methods: Gene expression differences between metastatic melanoma and melanoma in situ in 472 patients from the TCGA database were analyzed. The target gene Ang-2 was screened. A clinical study was conducted to analyze the correlation between Ang-2 expression in CMM and tumor-associated lymphangiogenesis. A total of 42 patients with primary CMM who underwent extended tumor resection procedures at the Affiliated Hospital of Jiangsu University were included in this study. Clinical data (gender, age, lymph node metastasis, Breslow thickness, and clinical stage) were collected. The expression levels of both Ang-2 and lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) proteins were detected by immunohistochemistry (IHC). Lymphatic vascular density (LVD) was counted by using LYVE-1 to label lymphatic endothelial cells (LECs) in peritumoral and intratumoral areas per high-magnification field of view. Statistical analysis was performed using the Pearson correlation test and Student's t-test. Results: Using the TCGA database, it was found that the gene expression level of Ang-2 in 368 cases of metastatic melanoma was significantly higher than that in 104 cases of melanoma in situ. Correlation analysis showed a significant relationship between Ang-2 and LYVE-1, and vascular endothelial growth factor receptor 3(VEGFR3) expression, respectively, in CMM. Moreover, the optimal cutoff value of survival analysis showed that high Ang-2 expression in CMM had a worse prognosis, based on data from the TCGA database. Our research showed that Ang-2 was more highly expressed in the group of patients with lymph node metastasis and in the group of stage 3C-4 patients than in the group of patients with no lymph node metastasis and in the group of stage 0-3B patients. Our research also showed that LVD in the group of patients with lymph node metastasis and in the group of stage 3C-4 patients was significantly higher than that in the group of no lymph node metastasis and in the group of stage 0-3B patients, respectively. Breslow thickness also correlated with Ang-2 expression and LVD. Ang-2 expression was not related to sex or age. Ang-2 expression was obviously correlated with LVD. Conclusion: An evaluation of Ang-2 expression and LVD can be used to predict the risk of tumor lymphatic metastasis and determine the prognosis of CMM. These results may also provide a new clinical treatment strategy for CMM.

Diagnostic and prognostic value of Ang-2 in ARDS: a systemic review and meta-analysis.

BACKGROUND: To investigate the diagnostic and prognostic value of angiopoietin-2 (Ang-2) for acute respiratory distress syndrome (ARDS). METHODS: Seven databases (4 English and 3 Chinese databases) were searched, the quality was evaluated by QUADAS-2 and GRADE profile. The bivariate model was employed to combine area under the curve (AUC), pooled sensitivity (pSEN) and pooled specificity (pSPE), the Fagan's nomogram was employed for evaluating clinical utility. This study was registered in PROSPERO (NO.CRD42022371488). RESULTS: 18 eligible studies comprising 27 datasets (12 diagnostic and 15 prognostic datasets) were included for meta-analysis. For diagnostic analysis, Ang-2 yielded an AUC of 0.82, with a pSEN of 0.78 and a pSPE of 0.74; in clinical utility analysis, a pretest probability of 50% regulated the post probability positive (PPP) of 75% and the post probability negative (PPN) of 23%. In prognostic analysis, Ang-2 yielded an AUC of 0.83, with a pSEN of 0.69, a pSPE of 0.81, and good clinical utility (a pretest probability of 50% regulated the PPP of 79% and the PPN of 28%). Heterogeneity existed in both diagnostic and prognostic analysis. CONCLUSIONS: Ang-2 demonstrates promising diagnostic and prognostic capabilities as a noninvasive circulating biomarker for ARDS, especially in the Chinese population. It is advisable to dynamically monitor Ang-2 in critically ill patients both suspected and with confirmed ARDS.