Angiogenic Pathways Research Articles

Pan-Cancer Single-Cell Transcriptomic Analysis Reveals Divergent Expression of Embryonic Proangiogenesis Gene Modules in Tumorigenesis.

Angiogenesis is indispensable for the sustained survival and progression of both embryonic development and tumorigenesis. This intricate process is tightly regulated by a multitude of pro-angiogenic genes. The presence of gene modules facilitating angiogenesis has been substantiated in both embryonic development and the context of tumor proliferation. However, it remains unresolved whether the pro-angiogenic gene modules expressed during embryonic development also exist in tumors. This study performed a pan-cancer single-cell RNA sequencing (scRNA-seq) analysis on samples from 332 patients across seven cancer types: thyroid carcinoma, lung cancer, breast cancer, hepatocellular carcinoma, colorectal cancer, ovarian carcinoma, and prostate adenocarcinoma. Data processing was carried out using the Seurat R package, with rigorous quality control to filter high-quality cells and mitigate batch effects across datasets. We used principal component analysis (PCA), shared nearest neighbor graph-based clustering, and Uniform Manifold Approximation and Projection (UMAP) to visualize cell types and identify distinct cell clusters. Myeloid cell subpopulations were further analyzed for the expression of embryonic pro-angiogenic gene modules (EPGM) and tumor pro-angiogenic gene modules (TPGM). The analysis identified nine major cell types within the tumor microenvironment, with myeloid cells consistently exhibiting elevated expression of both tumor pro-angiogenic gene modules (TPGM) and EPGM across all tumor types. In particular, myeloid cells, including macrophages and monocytes, showed high EPGM expression, indicating an active role of embryonic pro-angiogenesis pathways in tumors. A subset analysis revealed 20 distinct myeloid subtypes with varying EPGM and TPGM expression across different cancers. Treatment and disease stage influenced these gene expressions, with certain subtypes, such as HSPAhi/STAT1+ macrophages in breast cancer, displaying reduced pro-angiogenic gene activity post-treatment. This study provides evidence that tumors may exploit EPGM to enhance vascularization and support sustained growth, as evidenced by the elevated EPGM expression in tumor-associated myeloid cells. The consistent presence of EPGM in TAMs across multiple cancer types suggests a conserved mechanism wherein tumors harness embryonic angiogenic pathways to facilitate their progression. Distinct EPGM expression patterns in specific myeloid cell subsets indicate potential therapeutic targets, particularly in cases where EPGM activation contributes to resistance against anti-angiogenic therapies. These findings shed new light on the molecular mechanisms underlying tumor angiogenesis and highlight the prognostic relevance of EPGM expression in cancer, underscoring its potential as a biomarker for clinical applications.

Proliferative Diabetic Retinopathy Microenvironment Drives Microglial Polarization and Promotes Angiogenesis and Fibrosis via Cyclooxygenase-2/Prostaglandin E2 Signaling

Diabetic retinopathy (DR) is the leading cause of visual impairment, particularly in the proliferative form (proliferative DR [PDR]). The impact of the PDR microenvironment on microglia, which are the resident immune cells in the central nervous system, and the specific pathological changes it may induce remain unclear. This study aimed to investigate the role of microglia in the progression of PDR under hypoxic and inflammatory conditions. We performed a comprehensive gene expression analysis using human-induced pluripotent stem cell-derived microglia under different stimuli (dimethyloxalylglycine (DMOG), lipopolysaccharide (LPS), and DMOG + LPS) to mimic the hypoxic inflammatory environment characteristic of PDR. Principal component analysis revealed distinct gene expression profiles, with 76 genes synergistically upregulated under combined stimulation. Notably, prostaglandin-endoperoxide synthase 2 (encoding cyclooxygenase (COX)-2) exhibited the most pronounced increase, leading to elevated prostaglandin E2 (PGE2) levels and driving pathological angiogenesis and inflammation via the COX-2/PGE2/PGE receptor 2 signaling axis. Additionally, the upregulation of the fibrogenic genes snail family transcriptional repressor 1 and collagen type I alpha 1 chain suggested a role for microglia in fibrosis. These findings underscore the critical involvement of microglia in PDR and suggest that targeting both the angiogenic and fibrotic pathways may present new therapeutic strategies for managing this condition.

Flavonoid-Mediated Suppression of Tumor Angiogenesis: Roles of Ang-Tie/PI3K/AKT.

Angiogenesis is a process involved in the formation of new blood capillaries from pre-existing ones. It is regulated by several anti-angiogenic molecules involved in tumor growth and metastasis. The endothelial angiopoietin Ang-Tie/PI3K/AKT growth receptor pathway is necessary for healthy vascular development. The activation of AKT is controlled by a multistep process involving phosphoinositide 3-kinase (PI3K). This article aims to provide an overview of the role and mechanism of the Ang-Tie/PI3K/AKT signaling pathways and the potential of flavonoids as anti-angiogenic drugs. Flavonoids have shown great potential in preventing angiogenesis by targeting signaling pathways and exhibit additional anti-cancer properties. Research studies have revealed that the currently available anti-angiogenic drugs do not meet the safety and efficacy standards for treating tumor growth. Phytocompounds have long been a valuable resource for the development of novel therapeutic drugs. This article explores recent findings explaining the role and mechanism of the Ang-Tie/PI3K/AKT signaling pathways, as well as the interaction of flavonoids with angiogenic signaling pathways as a novel therapeutic approach. Several investigations have shown that synergistic studies of natural phytocompounds have great potential to target these pathways to inhibit tumor growth. Therefore, flavonoid-based medications may offer a more effective synergistic strategy to treat cancer.

Phlebotomy-induced anemia reduces oxygen-induced retinopathy severity and dampens retinal developmental transcriptomic pathways in rats.

Phlebotomy-induced-anemia (PIA), which induces tissue hypoxia and angiogenesis, occurs universally among infants at risk for severe retinopathy of prematurity (ROP). We hypothesized that PIA exacerbates pathologic retinal neovascularization in ROP. We induced PIA to a hematocrit of 18% among rats undergoing the established 50/10 oxygen-induced retinopathy (OIR) model. Rats were euthanized at P15 and P20, during the avascular and neovascular phases of OIR, respectively. Retinal vascular morphometry, cytokine/chemokine concentrations, transcriptomes, and mRNA expression of angiogenic and iron-deficiency markers were compared to non-PIA controls. In OIR, PIA decreased percent avascular area at P15 by 35%, percent neovascular area at P20 by 42%, and select pro-inflammatory cytokine/chemokine concentrations at both time points. At P20, PIA increased mRNA expression of angiopoietin 2/ vascular endothelial growth factor-A 2-fold and transferrin and transferrin receptor 5-fold. RNA sequencing showed dampened pathways of angiogenesis, inflammation, and neural development in anemic OIR females. Contrary to our hypothesis, PIA decreased OIR severity and retinal cytokine and chemokine levels and dampened transcriptomic pathways central to retinal vascular and neural development in neonatal rats. These data suggest PIA provides a protective effect from OIR. Further investigation into the functional effect of these molecular changes is warranted. This is the first preclinical study to investigate the impact of neonatal anemia on oxygen-induced retinopathy (OIR) outcomes. This study adds to the literature that anemia decreases neovascularization, decreases cytokine and chemokine levels, and dampens angiogenic and neural transcriptomic pathways in the rat 50/10 OIR model. The study identifies a sex-specific transcriptomic response to anemia in the 50/10 OIR model, with females primarily impacted.

S1701, A Randomized Phase 2 Trial of Carboplatin-Paclitaxel With and Without Ramucirumab in Patients With Locally Advanced, Recurrent, or Metastatic Thymic Carcinoma

IntroductionThymic carcinoma is a rare and aggressive malignancy with few treatment options. Preclinical studies suggested that targeting the angiogenic pathway may be beneficial in this disease. MethodsThis randomized phase 2 trial enrolled patients with unresectable, locally advanced, recurrent, or metastatic thymic carcinoma. Patients were randomized to receive carboplatin-paclitaxel with or without ramucirumab. The primary end point was progression-free survival (PFS) and secondary end points included response by Response Evaluation Criteria in Solid Tumors, disease control, toxicity, and overall survival. The primary analysis was done using a one-sided 10%-level log-rank test. Target sample size was 66 patients. ResultsBetween 2018 and 2022, 21 patients enrolled to ramucirumab plus carboplatin-paclitaxel (RCP, n = 8) and to the control arm (carboplatin-paclitaxel [CP], n = 13) with one patient on CP not meeting eligibility criteria. Owing to slow accrual, the study was terminated early by the Data and Safety Monitoring Board. Of the 20 eligible patients, eight on RCP and nine on CP received protocol treatment. PFS was not statistically different (hazard ratio = 0.51, 80% confidence interval [CI]: 0.24–1.09, p = 0.13). There were no grade 4 or higher treatment-related adverse events with RCP, although 50% experienced grade 3 adverse events, in which one patient had a grade 3 thromboembolic event. Among nine assessable patients for toxicity on CP, one patient (11%) encountered grade 4 neutropenia and one patient (11%) reported grade 3 thromboembolic events. Response rates favored the RCP arm, with an 88% (seven of eight, 80% CI: 59%–99%) response rate compared with 40% (four of 10, 80% CI: 19%–65%) on CP arm (p = 0.04). Disease control rate was higher in the RCP arm (100% versus 70%, p = 0.09). At the time of analysis, as only one death has been reported, overall survival remains immature. ConclusionsAccrual to this population is challenging, and the study was closed early because of feasibility. Although PFS was not statistically better with RCP, the hazard ratio was 0.51 and the lack of significance was likely due to small sample sizes. Notably, addition of ramucirumab to CP led to higher response rates than CP alone. Future research should consider exploring larger multicenter trials and other combinations to improve outcomes. Challenges in enrollment emphasize the need for innovative strategies and larger collaborations in rare malignancies such as thymic carcinoma.

Unveiling the antitumor synergy between pazopanib and metformin on lung cancer through suppressing p-Akt/ NF-κB/ STAT3/ PD-L1 signal pathway

Pazopanib, an inhibitor of the VEGF receptor tyrosine kinase, has demonstrated significant antitumor effects in lung cancer. However, its application as a standard treatment for this type of cancer is limited by its drug resistance and toxicity. Metformin has the potential to combat lung cancer by modifying the tumor’s immune microenvironment.In this study, we investigated the potential antitumor effects and the associated underlying molecular mechanisms of the combination of pazopanib and metformin in lung cancer. In vitro studies were conducted using the A549 and H460 lung cancer cell lines, whereas urethane-induced lung cancer-bearing mice were used for in vivo assessments. The urethane-induced mice received oral administration of pazopanib (50 mg/kg) and/or metformin (250 mg/kg) for a duration of 21 days.The results indicated that the MTT assay demonstrated a combined cytotoxic effect of the pazopanib/metformin combination in H460 and A549 cells, as evidenced by CI and DRI analyses. The observed increase in annexin V levels and the corresponding increase in Caspase-3 activity strongly suggest that this combination induced apoptosis.Furthermore, the pazopanib/metformin combination significantly inhibited the p-Akt/NF-κB/IL-6/STAT3, HIF1α/VEGF, and TLR2/TGF-β/PD-L1 pathways while also increasing CD8 expression in vivo. Immunohistochemical analysis revealed that these antitumor mechanisms were manifested by the suppression of the proliferation marker Ki67. In conclusion, these findings revealed that metformin augments the antitumor efficacy of pazopanib in lung cancer by simultaneously targeting proliferative, angiogenic, and immunogenic signaling pathways, metformin enhances the antitumor effectiveness of pazopanib in lung cancer, making it a promising therapeutic option for lung cancer.

Exploring angiogenic pathways in breast cancer: Clinicopathologic correlations and prognostic implications based on gene expression profiles from a large-scale genomic dataset

Exploring angiogenic pathways in breast cancer: Clinicopathologic correlations and prognostic implications based on gene expression profiles from a large-scale genomic dataset

Preventive effects of transcutaneous CO2 application on disuse osteoporosis and muscle atrophy in a rat hindlimb suspension model

We previously demonstrated that transcutaneous CO2 application promotes muscle fiber-type switching, fracture healing, and osteogenesis by increasing blood flow and angiogenesis. Here, we aimed to investigate the preventive effects of transcutaneous CO2 application on disuse osteoporosis and muscle atrophy in a rat hindlimb suspension model. Eleven-week-old male Sprague-Dawley rats were divided into hindlimb suspension (HS), HS with transcutaneous CO2 application (HSCO2), and control groups. HSCO2 rats were administered transcutaneous 100 % CO2 gas in their bilateral hindlimbs, five times a week for 20 min. After 3 weeks, we harvested the gastrocnemius, femur, and tibia for assessment. Histological analysis revealed a significant decrease in the gastrocnemius myofiber cross-sectional area in HS rats compared to the control rats, whereas HSCO2 rats exhibited a significant increase compared to HS rats. Micro-computed tomography showed significant bone atrophy in the trabecular and cortical bones of the femur in HS rats compared to those of the control rats, whereas significant improvement was noted in HSCO2 rats. Histological analysis of the proximal tibia revealed more marrow adipose tissue in the HS rats than in the control rats. However, in the HSCO2 rats, fewer marrow adipose tissue and osteoclasts were observed. Moreover, HSCO2 rats had more osteoblasts and higher expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and vascular endothelial growth factor (VEGF) than the HS rats. The gastrocnemius and distal femur of HSCO2 rats also exhibited elevated PGC-1α and VEGF expression and upregulation of the myogenesis markers and osteogenesis markers compared to those of HS rats. This treatment effectively prevented disuse osteoporosis and muscle atrophy by promoting local angiogenesis and blood flow. PGC-1α is crucial for promoting this angiogenic pathway. Transcutaneous CO2 application may be a novel preventive procedure for disuse osteoporosis and muscle atrophy, complementing medication and rehabilitation.

Research Progress on Anti-angiogenesis Drugs in Hepatocellular Carcinoma

Primary liver cancer is the sixth most prevalent cancer worldwide and ranked in third for cancer-related mortality rate. Hepatocellular carcinoma (HCC) accounts for about 90% of all primary liver cancers. High vascularization of HCC implies the significance of angiogenesis in the development and pathogenesis of HCC. Several angiogenic pathways have been identified as being dysregulated in HCC, highlighting potential therapeutic targets for the treatment of HCC. In 2007, sorafenib was approved as the standard first-line treatment for advanced HCC, catapulting the therapeutic approach of HCC into the avenue of targeted therapy. In recent years, the approval of several novel targeted drugs and the progress in combination of immunotherapy and targeted therapies provide more alternatives for the treatment of HCC. The progress of anti-angiogenesis therapies in HCC over the past few decades is reviewed and the future prospect of anti-angiogenesis therapy for HCC is also discussed.

Exploring antithrombotic mechanisms and effective constituents of Lagopsis supina using an integrated strategy based on network pharmacology, molecular docking, metabolomics, and experimental verification in rats

Ethnopharmacological relevanceThrombosis is a common cause of morbidity and mortality worldwide. Lagopsis supina (Stephan ex Willd.) Ikonn.-Gal. ex Knorring is an ancient Chinese herbal medicine used for treating thrombotic diseases. Nevertheless, the antithrombotic mechanisms and effective constituents of this plant have not been clarified. Aim of the studyThis work aimed to elucidate the pharmacodynamics and mechanism of L. supina against thrombosis. Materials and methodsSystematic network pharmacology was used to explore candidate effective constituents and hub targets of L. supina against thrombosis. Subsequently, the binding affinities of major constituents with core targets were verified by molecular docking analysis. Afterward, the therapeutic effect and mechanism were evaluated in an arteriovenous bypass thrombosis rat model. In addition, the serum metabolomics analysis was conducted using ultra-high performance liquid chromatography coupled with Q-Exactive mass spectrometry. ResultsA total of 124 intersected targets of L. supina against thrombosis were predicted. Among them, 24 hub targets were obtained and their mainly associated with inflammation, angiogenesis, and thrombosis approaches. Furthermore, 9 candidate effective constituents, including (22E,24R)-5α,8α-epidioxyergosta-6,22-dien-3β-ol, aurantiamide, (22E,24R)-5α,8α-epidioxyergosta-6,9 (11),22-trien-3β-ol, lagopsinA, lagopsin C, 15-epi-lagopsin C, lagopsin D, 15-epi-lagopsin D, and lagopsin G in L. supina and 6 potential core targets (TLR-4, TNF-α, HIF-1α, VEGF-A, VEGFR-2, and CLEC1B) were acquired. Then, these 9 constituents demonstrated strong binding affinities with the 6 targets, with their lowest binding energies were all less than −5.0 kcal/mol. The antithrombotic effect and potential mechanisms of L. supina were verified, showing a positively associated with the inhibition of inflammation (TNF-α, IL-1β, IL-6, IL-8, and IL-10) and coagulation cascade (TT, APTT, PT, FIB, AT-III), promotion of angiogenesis (VEGF), suppression of platelet activation (TXB2, 6-keto-PGF1α, and TXB2/6-keto-PGF1α), and prevention of fibrinolysis (t-PA, u-PA, PAI-1, PAI-1/t-PA, PAI-1/u-PA, and PLG). Finally, 14 endogenous differential metabolites from serum samples of rats were intervened by L. supina based on untargeted metabolomics analysis, which were closely related to amino acid metabolism, inflammatory and angiogenic pathways. ConclusionOur integrated strategy based on network pharmacology, molecular docking, metabolomics, and in vivo experiments revealed for the first time that L. supina exerts a significant antithrombotic effect through the inhibition of inflammation and coagulation cascade, promotion of angiogenesis, and suppression of platelet activation. This paper provides novel insight into the potential of L. supina as a candidate agent to treat thrombosis.

A Splice Form of VEGF, a Potential Anti-Angiogenetic Form of Head and Neck Squamous Cell Cancer Inhibition.

Angiogenesis, primarily mediated by vascular endothelial growth factor (VEGF), is a fundamental step in the progression and metastasis of head and neck squamous cell carcinoma (HNSCC). Traditional anti-angiogenic therapies that target the VEGF pathway have shown promise but are often associated with significant side effects and variable efficacy due to the complexity of the angiogenic signaling pathway. This review highlights the potential of a specific VEGF splice form, VEGF165b, as an innovative therapeutic target for HNSCC. VEGF165b, unlike standard VEGF, is a natural inhibitor that binds to VEGF receptors without triggering pro-angiogenic signaling. Its distinct molecular structure and behavior suggest ways to modulate angiogenesis. This concept is particularly relevant when studying HNSCC, as introducing VEGF165b's anti-angiogenic properties offers a novel approach to understanding and potentially influencing the disease's dynamics. The review synthesizes experimental evidence suggesting the efficacy of VEGF165b in inhibiting tumor-induced angiogenesis and provides insight into a novel therapeutic strategy that could better manage HNSCC by selectively targeting aberrant vascular growth. This approach not only provides a potential pathway for more targeted and effective treatment options but also opens the door to a new paradigm in anti-angiogenic therapy with the possibility of reduced systemic toxicity. Our investigation is reshaping the future of HNSCC treatment by setting the stage for future research on VEGF splice variants as a tool for personalized medicine.

Epigenetics and Control of Tumor Angiogenesis in Melanoma: An Update with Therapeutic Implications.

Angiogenesis, the formation of new blood vessels from pre-existing ones, is a crucial process in the progression and metastasis of melanoma. Recent research has highlighted the significant role of epigenetic modifications in regulating angiogenesis. This review comprehensively examines the current understanding of how epigenetic mechanisms, including DNA methylation, histone modifications, and non-coding RNAs, influence angiogenic pathways in melanoma. DNA methylation, a key epigenetic modification, can silence angiogenesis inhibitors such as thrombospondin-1 and TIMP3 while promoting pro-angiogenic factors like vascular endothelial growth factor (VEGF). Histone modifications, including methylation and acetylation, also play a pivotal role in regulating the expression of angiogenesis-related genes. For instance, the acetylation of histones H3 and H4 is associated with the upregulation of pro-angiogenic genes, whereas histone methylation patterns can either enhance or repress angiogenic signals, depending on the specific histone mark and context. Non-coding RNAs, particularly microRNAs (miRNAs) further modulate angiogenesis. miRNAs, such as miR-210, have been identified as key regulators, with miR-9 promoting angiogenesis by targeting E-cadherin and enhancing the expression of VEGF. This review also discusses the therapeutic potential of targeting epigenetic modifications to inhibit angiogenesis in melanoma. Epigenetic drugs, such as DNA methyltransferase inhibitors (e.g., 5-azacytidine) and histone deacetylase inhibitors (e.g., Vorinostat), have shown promise in preclinical models by reactivating angiogenesis inhibitors and downregulating pro-angiogenic factors. Moreover, the modulation of miRNAs and lncRNAs presents a novel approach for anti-angiogenic therapy.

3D physiologically-informed deep learning for drug discovery of a novel vascular endothelial growth factor receptor-2 (VEGFR2)

Angiogenesis is an essential process in tumorigenesis, tumor invasion, and metastasis, and is an intriguing pathway for drug discovery. Targeting vascular endothelial growth factor receptor 2 (VEGFR2) to inhibit tumor angiogenic pathways has been widely explored and adopted in clinical practice. However, most drugs, such as the Food and Drug Administration –approved drug axitinib (ATC code: L01EK01), have considerable side effects and limited tolerability. Therefore, there is an urgent need for the development of novel VEGFR2 inhibitors. In this study, we propose a novel strategy to design potential candidates targeting VEGFR2 using three-dimensional (3D) deep learning and structural modeling methods. A geometric-enhanced molecular representation learning method (GEM) model employing a graph neural network (GNN) as its underlying predictive algorithm was used to predict the activity of the candidates. In the structural modeling method, flexible docking was performed to screen data with high affinity and explore the mechanism of the inhibitors. Small -molecule compounds with consistently improved properties were identified based on the intersection of the scores obtained from both methods. Candidates identified using the GEM-GNN model were selected for in silico modeling using molecular dynamics simulations to further validate their efficacy. The GEM-GNN model enabled the identification of candidate compounds with potentially more favorable properties than the existing drug, axitinib, while achieving higher efficacy.

Wolbachia Promotes an Anti-Angiogenic Response Using an In Vitro Model of Vascular Endothelial Cells in Relation to Heartworm Disease.

Heartworm disease caused by Dirofilaria immitis is a vector-borne zoonotic disease responsible for the infection of mainly domestic dogs and cats, or these are those for which the most data are known. Humans are an accidental host where a benign, asymptomatic pulmonary nodule may originate. Dirofilaria immitis also harbours the endosymbiont bacteria of the genus Wolbachia, which play a role in moulting, embryogenesis, inflammatory pathology, and immune response. When Wolbachia sp. is released into the bloodstream, endothelial and pulmonary damage is exacerbated, further encouraging thrombus formation and pulmonary hypertension, facilitating congestive heart failure and death of the animal. Previous studies have shown that parasite excretory/secretory products are able to activate the pro-angiogenic pathway (formation of new vessels) to facilitate parasite survival. The aim of this study was to analyse the role of Wolbachia sp. and its relationship with the cellular processes and the angiogenic pathway in a model of human endothelial cells in vitro. The use of recombinant Wolbachia Surface Protein (rWSP) showed that its stimulation exerted an anti-angiogenic effect by detecting an increase in the production of VEGFR-1/sFlt1 and sEndoglin and did not affect the production of VEGFR-2 and mEndoglin (pro-angiogenic molecules). Furthermore, it did not stimulate cell proliferation or migration, although it did negatively stimulate the formation of pseudocapillaries, slowing down this process. These cellular processes are directly related to the angiogenic pathway so, with these results, we can conclude that Wolbachia sp. is related to the stimulation of the anti-angiogenic pathway, not facilitating the survival of D. immitis in vascular endothelium.

Anticancer Potential of Flavonoids: Their Role in Cancer Prevention and Health Benefits.

The term "flavonoid" encompasses a group of plant compounds, predominantly flavonoids, present in fruits, vegetables, and other plant-based foods. These compounds deliver significant health benefits, including potent antioxidant properties that protect cells from free radicals, thereby mitigating aging and disease. We assessed study quality and bias using the Cochrane Risk of Bias tool and the Newcastle-Ottawa Scale. Inclusion criteria specified that the studies must examine a natural flavonoid from fruits, must involve animal or human trials, must be original studies, and must be English articles on the flavonoid's health and cancer-prevention effects, excluding conference abstracts and single-case studies. We conducted a comprehensive search of major databases including PubMed, Web of Science, Embase, SCOPUS, and Google Scholar, reviewing six clinical trials with total sample sizes of over 50 to 1500 participants. The results indicate that consuming flavonoid-rich fruits can aid in cancer prevention by targeting angiogenic and cancer-protective pathways. We specifically selected tomatoes, mulberries, Amazon grapes, apples, and citrus fruits due to their well-documented high levels of flavonoids and the robust clinical evidence supporting their physiological effects. In particular, citrus fruits contain additional beneficial phytochemicals that complement the action of flavonoids, enhancing their overall health effects. The anti-cancer mechanisms of flavonoids are not well-defined in the scientific literature, suggesting a gap that this study aims to address. Our study provides novel contributions by demonstrating how flavonoid supplementation induces anti-cancer effects through angiogenesis, anti-inflammatory actions, antioxidant-induced apoptosis, and modulation of pathways like PI3K/Akt and MAPK. These effects were particularly notable in the prevention and progression of breast, colon, liver, and lung cancers, with statistical significance (p < 0.05). By elucidating specific mechanisms and pathways, this study contributes to the understanding of flavonoids' role in cancer prevention and underscores the potential for developing natural anti-cancer therapeutics through the inclusion of flavonoid-rich fruits in the diet. Future research should focus on randomized controlled trials assessing long-term effects of flavonoid supplementation in diverse populations, exploring optimal dosages, and understanding interactions with conventional cancer therapies to provide comprehensive evidence for clinical applications.

The BCR::ABL1 tyrosine kinase inhibitors ponatinib and nilotinib differentially affect endothelial angiogenesis and signalling.

BCR::ABL1 inhibitors, the treatment of choice for the majority of patients with chronic myeloid leukaemia (CML), can cause vascular side effects that vary between agents. The exact underlying mechanisms are still poorly understood, but the vascular endothelium has been proposed as a site of origin. The present study investigates the effects of three BCR::ABL1 inhibitors, ponatinib, nilotinib and imatinib, on angiogenesis and signalling in human endothelial cells in response to vascular endothelial growth factor (VEGF). The experiments were performed in endothelial cells isolated from human umbilical veins. After exposure to imatinib, ponatinib and nilotinib, the angiogenic capacity of endothelial cells was assessed in spheroid assays. VEGF-induced signalling pathways were examined in Western blotting experiments using different specific antibodies. RNAi technology was used to downregulate proteins of interest. Intracellular cGMP levels were measured by ELISA. Imatinib had no effect on endothelial function. Ponatinib inhibited VEGF-induced sprouting, while nilotinib increased spontaneous and VEGF-stimulated angiogenesis. These effects did not involve wild-type ABL1 or ABL2, as siRNA-mediated knockdown of these kinases did not affect angiogenesis and VEGF signalling. Consistent with their effects on sprouting, ponatinib and nilotinib affected angiogenic pathways in opposite directions. While ponatinib inhibited VEGF-induced signalling and cGMP formation, nilotinib activated angiogenic signalling, in particular phosphorylation of extracellular signal-regulated kinase 1/2 (Erk1/2). The latter occurred in an epidermal growth factor receptor (EGFR)-dependent manner possibly via suppressing Fyn-related kinase (FRK), a negative regulator of EGFR signalling. Both, pharmacological inhibition of Erk1/2 or EGFR suppressed nilotinib-induced angiogenic sprouting. These results support the notion that the vascular endothelium is a site of action of BCR::ABL1 inhibitors from which side effects may arise, and that the different vascular toxicity profiles of BCR::ABL1 inhibitors may be due to their different actions at the molecular level. In addition, the as yet unknown pro-angiogenic effect of nilotinib should be considered in the treatment of patients with comorbidities associated with pathological angiogenesis, such as ocular disease, arthritis or obesity.

Single-cell atlas of the human brain vasculature across development, adulthood and disease

A broad range of brain pathologies critically relies on the vasculature, and cerebrovascular disease is a leading cause of death worldwide. However, the cellular and molecular architecture of the human brain vasculature remains incompletely understood1. Here we performed single-cell RNA sequencing analysis of 606,380 freshly isolated endothelial cells, perivascular cells and other tissue-derived cells from 117 samples, from 68 human fetuses and adult patients to construct a molecular atlas of the developing fetal, adult control and diseased human brain vasculature. We identify extensive molecular heterogeneity of the vasculature of healthy fetal and adult human brains and across five vascular-dependent central nervous system (CNS) pathologies, including brain tumours and brain vascular malformations. We identify alteration of arteriovenous differentiation and reactivated fetal as well as conserved dysregulated genes and pathways in the diseased vasculature. Pathological endothelial cells display a loss of CNS-specific properties and reveal an upregulation of MHC class II molecules, indicating atypical features of CNS endothelial cells. Cell–cell interaction analyses predict substantial endothelial-to-perivascular cell ligand–receptor cross-talk, including immune-related and angiogenic pathways, thereby revealing a central role for the endothelium within brain neurovascular unit signalling networks. Our single-cell brain atlas provides insights into the molecular architecture and heterogeneity of the developing, adult/control and diseased human brain vasculature and serves as a powerful reference for future studies.

Role of Protein Phosphatases in Tumor Angiogenesis: Assessing PP1, PP2A, PP2B and PTPs Activity.

Tumor angiogenesis, the formation of new blood vessels to support tumor growth and metastasis, is a complex process regulated by a multitude of signaling pathways. Dysregulation of signaling pathways involving protein kinases has been extensively studied, but the role of protein phosphatases in angiogenesis within the tumor microenvironment remains less explored. However, among angiogenic pathways, protein phosphatases play critical roles in modulating signaling cascades. This review provides a comprehensive overview of the involvement of protein phosphatases in tumor angiogenesis, highlighting their diverse functions and mechanisms of action. Protein phosphatases are key regulators of cellular signaling pathways by catalyzing the dephosphorylation of proteins, thereby modulating their activity and function. This review aims to assess the activity of the protein tyrosine phosphatases and serine/threonine phosphatases. These phosphatases exert their effects on angiogenic signaling pathways through various mechanisms, including direct dephosphorylation of angiogenic receptors and downstream signaling molecules. Moreover, protein phosphatases also crosstalk with other signaling pathways involved in angiogenesis, further emphasizing their significance in regulating tumor vascularization, including endothelial cell survival, sprouting, and vessel maturation. In conclusion, this review underscores the pivotal role of protein phosphatases in tumor angiogenesis and accentuate their potential as therapeutic targets for anti-angiogenic therapy in cancer.

Aberrant angiogenic signaling pathways: Accomplices in ovarian cancer progression and treatment

Ovarian cancer is one of the most common malignant tumors in women, and treatment options are limited. Despite efforts to adjust cancer treatment models and develop new methods, including tumor microenvironment (TME) therapy, more theoretical support is needed. Increasing attention is being given to antiangiogenic measures for TME treatment. Another important concept in ovarian cancer TME is angiogenesis, where tumor cells obtain nutrients and oxygen from surrounding tissues through blood vessels to support further expansion and metastasis. Many neovascularization signaling pathways become imbalanced and hyperactive during this process. Inhibiting these abnormal pathways can yield ideal therapeutic effects in patients, even by reversing drug resistance. However, these deep TME signaling pathways often exhibit crosstalk and correlation. Understanding these interactions may be an important strategy for further treating ovarian cancer. This review summarizes the latest progress and therapeutic strategies for these angiogenic signaling pathways in ovarian cancer.

Landscape of Endometrial Cancer: Molecular Mechanisms, Biomarkers, and Target Therapy.

Endometrial cancer is one the most prevalent gynecological cancers and, unfortunately, has a poor prognosis due to low response rates to traditional treatments. However, the progress in molecular biology and understanding the genetic mechanisms involved in tumor processes offers valuable information that has led to the current classification that describes four molecular subtypes of endometrial cancer. This review focuses on the molecular mechanisms involved in the pathogenesis of endometrial cancers, such as genetic mutations, defects in the DNA mismatch repair pathway, epigenetic changes, or dysregulation in angiogenic or hormonal signaling pathways. The preclinical genomic and molecular investigations presented allowed for the identification of some molecules that could be used as biomarkers to diagnose, predict, and monitor the progression of endometrial cancer. Besides the therapies known in clinical practice, targeted therapy is described as a new cancer treatment that involves identifying specific molecular targets in tumor cells. By selectively inhibiting these targets, key signaling pathways involved in cancer progression can be disrupted while normal cells are protected. The connection between molecular biomarkers and targeted therapy is vital in the fight against cancer. Ongoing research and clinical trials are exploring the use of standard therapy agents in combination with other treatment strategies like immunotherapy and anti-angiogenesis therapy to improve outcomes and personalize treatment for patients with endometrial cancer. This approach has the potential to transform the management of cancer patients. In conclusion, enhancing molecular tools is essential for stratifying the risk and guiding surgery, adjuvant therapy, and cancer treatment for women with endometrial cancer. In addition, the information from this review may have an essential value in the personalized therapy approach for endometrial cancer to improve the patient's life.