Search Results (387)

Sunitinib, a tyrosine kinase inhibitor (TKI) targeting vascular endothelial growth factor receptors (VEGFRs) and platelet-derived growth factor receptors (PDGFRs), is widely used in renal cell carcinoma. A broad spectrum of thyroid dysfunctions has been observed during TKI therapy, yet their mechanisms and clinical progression remain only partially explained. A longitudinal case analysis of a woman with metastatic clear-cell renal cell carcinoma treated with cyclical sunitinib therapy (4 weeks on, 2 weeks off) was performed. Thyroid function tests, clinical symptoms, and ultrasound imaging findings were evaluated over time and compared with treatment exposure and dose adjustments. Baseline thyroid function was normal. During the third cycle, thyroid-stimulating hormone (TSH) increased markedly (33.44–41.26 mIU/L), with free thyroid hormones initially remaining within reference limits. TSH fluctuations corresponded to treatment intervals before stabilising into persistent hypothyroidism requiring levothyroxine replacement. Thyroid ultrasound revealed progressive parenchymal destruction and a reduction in gland volume from 18 mL to approximately 2 mL over three years. Endocrine management enabled maintenance of biochemical euthyroidism, and systemic oncological treatment continued without interruption. Sunitinib treatment may lead to progressive destructive hypothyroidism. Routine surveillance of thyroid function is essential, and timely levothyroxine therapy facilitates continued anticancer treatment and symptom control. Full article

Vascular endothelial growth factor 165 (VEGF₁₆₅) stands out as a pivotal isoform of the VEGF-A protein and is critically involved in various angiogenesis-related diseases. Consequently, it has emerged as a promising target for diagnosing and treating such conditions. Structurally, VEGF₁₆₅ forms a homodimer, and each of its constituting monomers comprises a receptor-binding domain (RBD) and a heparin-binding domain (HBD). These two domains are linked by a flexible linker, and thus the overall structure of VEGF₁₆₅ remains incompletely understood. Aptamers are known as potent drugs that interact with VEGF₁₆₅, and dimeric aptamers that can simultaneously interact with two distant domains are frequently adopted to improve the potency. However, designing such aptamer dimers faces challenges in regard to determining the appropriate length of the linker connecting the two aptamer fragments. To gain insight into this distance information, we here employ biased molecular dynamics (MD) simulations with the umbrella sampling method, with the distance between the two HBDs serving as a reaction coordinate. Our simulations reveal an overall preference for compact conformations with HBD-HBD distances below 3 nm, with the minimum of the potential of mean force located at 1.1 nm. We find that VEGF₁₆₅ with the optimal HBD-HBD distance forms hydrogen bonds with its receptor VEGFR-2 that well match experimentally known key hydrogen bonds. We then try to computationally design aptamer homodimers consisting of two del5-1 aptamers connected by various linker lengths to target VEGF₁₆₅. Collectively, our findings may provide quantitative guidelines for rationally designing high-affinity aptamers for targeting VEGF₁₆₅. Full article

Diabetes mellitus severely impairs skeletal muscle regeneration after injury, limiting satellite cell activation and angiogenesis and disrupting barrier integrity while increasing fibrosis. Hypobaric hypoxia has been proposed to improve the regenerative microenvironment through hypoxia-responsive signaling, but its temporal effects and the coordination between vascular and myogenic programs in diabetic muscle remain unclear. To clarify these processes, adult male mice were divided into five groups: diabetes mellitus control (DM), cardiotoxin-injured (CTX) diabetes assessed on days 7 and 14 (CTX7, CTX14), and hypobaric-hypoxia-treated diabetic injury assessed on days 7 and 14 (H+CTX7, H+CTX14). Animals in the hypoxia groups were exposed to a hypobaric hypoxia chamber for 8 h per day for 14 days. Fibrosis, angiogenic and myogenic markers, and endothelial junctional genes were examined using histology, immunofluorescence, immunoblotting, and qRT-PCR (Quantitative Real-Time PCR). Hypobaric hypoxia on day 7 enhanced HIF-1α (hypoxia-inducible factor 1 alpha), VEGF (vascular endothelial growth factor), eNOS (endothelial nitric oxide synthas), Kdr (kinase insert domain receptor, VEGFR-2), and Angpt2 (angiopoietin-2) expression, accompanied by simultaneous endothelial sprouting and early myogenic stimulation compared to CTX7. Improvements were observed in Angpt1 (angiopoietin-1), Cdh5 (cadherin-5, VE-cadherin), Emcn (endomucin), the Angpt1/Angpt2 ratio, and CD31 density. Myogenin and MyHC (myosin heavy chain) were induced with a reduction in eMyHC (embryonic myosin heavy chain) in accordance with stabilization of endothelium and maturation of fibers, which occurred by day 14. A decrease in fibrosis and an increase in the myofiber cross-sectional area occurred. These findings suggest that hypobaric hypoxia modulates HIF-1α signaling, which in turn induces the VEGF-Kdr-eNOS pathway and the angiopoietin–Tie2–VE-cadherin pathway. Together, these pathways coordinate vascular remodeling and myogenic regeneration, ultimately improving the structural and functional recovery of diabetic muscle. Full article

Vascular endothelial growth factor receptor 3 (VEGFR3) assumes a pivotal role in regulating the development and maintaining the structural integrity of the lymphatic system. Decreased activity of VEGFR3 can precipitate aplasia or hypoplasia of lymphatic system components, culminating in primary lymphedema. To date, numerous genetic variants have been identified within the FLT4 gene, which encodes VEGFR3; however, the majority of these remain uncharacterised and are classified as ‘variants of uncertain significance’. In preceding investigations involving FLT4 sequence analysis conducted on individuals presenting with primary lymphedema, we identified several rare genetic variants that possess the potential to modulate the functional activity of VEGFR3, including the heterozygous variant c.3175G>C (p.A1059P). Preliminary assessments encompassing clinical characteristics, family history, and predictive computational algorithms indicated that this variant was likely pathogenic. Consequently, this study presents the results of functional evaluation of the mutant VEGFR3 activity in cell models overexpressing the FLT4 variant c.3175G>C. VEGFC-dependent VEGFR3 phosphorylation and FLT4 expression were reduced in cells with c.3175G>C FLT4 variant compared to wild-type, confirming the pathogenic role of c.3175G>C in primary lymphedema. Full article

Background: Hypoxia-inducible factor-1α (HIF-1α) is a well-known transcriptional regulator that mediates a broad spectrum of cellular responses to hypoxia, including angiogenesis, extracellular matrix remodeling, and metabolic reprogramming. These activities can be achieved by upregulation of numerous genes, such as vascular endothelial growth factors, fibroblast growth factors, and platelet-derived growth factors, which are involved in the growth regulation of normal tissues and solid tumors. Notably, HIF-1α-mediated regulation of the solid tumor’s microenvironment effectively modulates tumor sensitivity to anticancer therapies and thereby can contribute to disease progression. Methods: The study was performed on breast, lung and prostate cancer cell lines. Protein expression was examined by western blotting. Antitumor activity of 2-ANPC was measured by syngeneic 4T1 breast cancer mouse model. Results: We show here that a 2-aminopyrrole derivative (2-amino-1-benzamido-5-(2-(naphthalene-2-yl)-2-oxoethylidene)-4-oxo-4,5-dihydro-1-H-pyrrole-3-carboxamide—2-ANPC), previously shown as a potent microtubule-targeting agent, effectively downregulates HIF-1α expression in a broad spectrum of cancer cell lines, including breast, lung, and prostate cancer. The downregulation of HIF-1α expression in 2-ANPC-treated cancer cells was due to enhanced proteasome-mediated degradation, whereas the proteasome inhibitor MG-132 effectively reversed this downregulation. 2-ANPC’s potency in downregulating HIF-1α was also shown in vivo by using the 4T1 breast cancer syngraft model. Importantly, this 2-aminopyrrole derivative also downregulated the expression of vascular endothelial growth factor receptors 1 and 3 (VEGFR1 and 3) in 4T1 tumors, which correlated with decreased tumor weight and size. As expected, an increase in apoptotic (i.e., cleaved caspase-3-positive) cells was detected in 4T1 tumors treated with 2-aminopyrrole derivative. Lastly, using various computational tools, we identified four potential binding sites for 2-ANPC to interact with HIF-1α, HIF-1β, and the p300 complex. Conclusions: Collectively, we show here, for the first time, that HIF-1α is a novel molecular target for the 2-aminopyrrole derivative (2-ANPC), thereby illustrating it as a potential scaffold for the development of potent chemotherapeutic agents with anti-angiogenic activity. Full article

Neurodegenerative diseases pose major clinical challenges partly due to the underappreciation of the brain’s vascular and clearance systems. Evidence suggests that neurovascular dysfunction and glymphatic impairment are early contributors to disease onset, preceding established markers such as protein aggregation. This review synthesizes recent advances in understanding how disruption of the neurovascular unit (NVU) and glymphatic pathways contributes to neurodegeneration. We analyzed published literature documenting the temporal relationship between vascular dysfunction, glymphatic clearance impairment, and subsequent neurodegenerative pathology, with a focus on identifying therapeutic targets within this axis. Current research demonstrates that blood-brain barrier BBB breakdown, pericyte dysfunction, and compromised cerebral perfusion precede protein aggregation in multiple neurodegenerative disorders. Glymphatic dysfunction, characterized by aquaporin-4 (AQP4) depolarization and abnormalities in meningeal lymphatic vessels, impairs the clearance of neurotoxic metabolites. Novel therapeutic opportunities include the preservation of pericyte function, restoration of AQP4 polarity, enhancement of meningeal lymphatic drainage via vascular endothelial growth factor-C (VEGF-C)/vascular endothelial growth factor receptor-3 VEGFR-3 signaling, and targeted modulation of microRNA and complement pathways that regulate neuroinflammation. By targeting the earliest vascular and glymphatic disruptions, emerging therapeutic strategies may halt or delay disease progression before irreversible neuronal loss occurs. This neurovascular-glymphatic approach represents an unexplored frontier that complements traditional protein-centric therapeutic paradigms, offering new possibilities for early intervention in neurodegenerative disorders. Full article

Kinases, which make up 20% of the druggable genome, are thought to be essential signaling enzymes. Protein phosphorylation is induced by protein kinases. Proliferation, the cell cycle, apoptosis, motility, growth, differentiation, and other biological processes are all regulated by kinases. Their dysregulation disrupts several cellular functions, leading to a variety of illnesses, the most important of which is cancer. As a result, kinases are thought to be crucial targets in a number of malignancies and other diseases. Researchers from all over the world are hard at work developing inhibitors using various chemical structures. The scaffolds of imidazole and benzimidazole provide a versatile structure for a variety of physiologically active substances. Moreover, they serve as specialized scaffolding for the creation of target-specific pharmaceuticals to address various diseases. This article seeks to illustrate the application of imidazole and benzimidazole frameworks in the formulation of inhibitors that target various tyrosine kinases, including fibroblast growth factor receptors (FGFRs), c-Met kinase, epidermal growth factor receptors (EGFRs), vascular endothelial growth factor receptors (VEGFRs), and FMS-like tyrosine kinase 3 (FLT3), from 2020 to the present. The major structure–activity correlations (SARs) of imidazole and benzimidazole derivatives were examined, and, also, a docking study highlighted the varied interactions occurring inside the active site of tyrosine protein kinases. The objective of this effort is to consolidate the fundamental structural information necessary for the synthesis of imidazole- or benzimidazole-based tyrosine kinase inhibitors with enhanced efficacy. Full article

Colon cancer (CC) is a common malignancy characterized by poor prognostic outcomes and considerable mortality. Oxaliplatin (OXP) is commonly used in the treatment of CC; however, its efficacy may be limited by side effects and the development of resistance. β-sitosterol (β-Sit), a phytosterol derived from plants, has been documented to be effective in the treatment of tumors. This study aimed to investigate the potential of β-Sit to enhance the antitumor efficacy of OXP in COLO-205 cells, focusing on apoptosis induction and suppression of the vascular endothelial growth factor A (VEGF-A)/survival pathway. Molecular docking studies were performed to assess the binding affinity of β-Sit with the target proteins B-cell lymphoma 2 (Bcl-2), phosphoinositide 3-kinase (PI3K), and VEGF receptor-2 (VEGFR-2). COLO-205 cells were treated with OXP, β-Sit, or a combination of OXP + β-Sit for 48 h. The combination treatment substantially lowered the IC₅₀ achieved with 3.24 µM of OXP and 36.01 µM of β-Sit, compared to 25.64 µM for OXP alone and 275.9 µM for β-Sit alone, demonstrating a pronounced synergistic impact. The combined therapy altered the cell cycle distribution by decreasing the number of cells in the G0/G, S, and G2/M phases, coupled with an increase in the Sub-G1 population. Furthermore, apoptosis was augmented by a shift in cell death from necrosis to late apoptosis, as indicated by an increased BAX/BCL2 ratio relative to each treatment alone. Moreover, the inhibitory effect on angiogenesis was enhanced via the reduction of VEGF-A, and β-catenin and nuclear factor κB (NF-κB-p65) were suppressed, thereby preventing the growth and survival of resistant cancer cells. Additionally, molecular docking supported high binding affinities of β-Sit to Bcl-2, PI3K, and VEGFR-2. This study highlights the potential of β-Sit to enhance the anti-cancer efficacy of OXP in CC. Full article

Uveal melanoma (UM) is the most prevalent primary intraocular tumor in adults. Transcription factor ZEB1 is one of the potential master regulators of melanocytes plasticity, because it is recognized as a “driver” of epithelial-to-mesenchymal transitions (EMTs) in carcinomas. We studied the correlation of tumor invasiveness with ZEB1 status and vascular endothelial growth factor/its receptor (VEGF-A/VEGFR2) in UM cells, and also with melanocyte’s differentiation rate. Eight UM cell cultures were characterized by melanosomes content using an ETM. ZEB1, VEGF-A and VEGFR2 levels in UM cells were detected by RT-PCR, Western blot, ELISA and flow cytometry. Effects of siRNA-dependent ZEB1 knockdown on UM cell proliferation and their sensitivity to the VEGF-A inhibitor Eylea (aflibercept) were tested by MTT and in a real-time proliferation assay. UMs with an invasive growth type can maintain a high degree of melanocyte differentiation. All ZEB1^low cells were obtained from spindle cell tumors. The sensitivity of UM cells to Eylea inversely correlated with the level of the VEGFR2 receptor. ZEB1 knockdown completely blocked VEGF-A production while anti-VEGF treatment stimulated ZEB1 increase. In UM cell cultures, ZEB1 is a positive regulator of VEGF-A expression. In addition, there is probably a ZEB1 feedback loop that is sensitive to a drop in VEGF-A concentration. The data obtained allow us to consider ZEB1 silencing as an auxiliary link for a combined strategy of killing UM cells. Full article

Pericytes produce vascular endothelial growth factor-A (VEGF-A; hereafter referred to as VEGF). VEGF inhibits pericyte proliferation and migration through enhanced VEGFR2 and PDGFRβ heterodimerization. Heterodimerization of these receptors on perivascular supporting cells, mediated by VEGF in culture, mitigates signaling through these receptors and promotes a quiescent phenotype. However, the detailed cellular mechanisms and the significance of these interactions in vivo require further investigation. The cell-autonomous activities of pericyte VEGF expression during vascular development and neovascularization remain unknown. Here we utilized mice conditionally lacking Vegfa in pericytes (Vegfa^PC) to examine its impact on retinal vascular development and pathological ocular neovascularization. Vascular integrity was also assessed in older mice using fundus imaging and fluorescein angiography. The lack of Vegfa pericyte expression delayed the initial spreading of the superficial layer of the retinal vasculature. Mice lacking Vegfa pericyte expression had similar numbers of retinal endothelial cells and arteries to their wild-type littermates. However, the number of pericytes was significantly reduced in younger Vegfa^PC mice but increased in more mature mice. In addition, pericyte Vegfa deficiency did not impact responses during oxygen-induced ischemic retinopathy and laser-induced choroidal neovascularization. Thus, pericyte VEGF expression plays a role during early stages of retinal vascular development with limited influence on mature retinal vascularization, its integrity, and neovascularization. Full article

Background/Objectives: Type 2 diabetes mellitus (T2DM) is a chronic and multifactorial metabolic disorder associated with genetic and environmental factors. Vascular endothelial growth factor (VEGF) plays a crucial role in angiogenesis and vascular homeostasis, and genetic polymorphisms in the VEGF signaling pathway have been linked to the T2DM development, progression, and complications. This scoping review investigated the association between VEGF gene and VEGF receptors single-nucleotide polymorphisms (SNPs) and susceptibility to T2DM and vascular complications. Methods: A thorough systematic review was performed utilizing scientific databases (PubMed, Web of Science, and Scopus) in March 2025. From an initial pool of 796 records, 59 relevant articles were selected for inclusion in the analysis. Results: The most frequently studied SNPs were rs2010963 (31/59), rs699947 (16/59), rs3025039 (15/59), rs833061 (11/59), rs1570360 (7/59) in the VEGFA gene and rs2071559(6/59) in VEGFR2. The studies include a diverse range of ethnic groups, including Asian, European and Middle Eastern populations. The main complications associated with these SNPs were microvascular conditions such as diabetic retinopathy (DR) (49/59), diabetic neuropathy (DPN) (6/59), diabetic nephropathy (DNP) (2/59), and as well as macrovascular complications including diabetic foot ulcers (DFU) (10/59). The results revealed that these polymorphisms, particularly rs3025039 and rs2010963, were more consistently associated with microvascular complications such as DR rather than with T2DM itself. The C allele of rs2010963 was associated with increased risk of DR in Indian populations, while no such association was observed in European. Similarly, the T allele of rs3025039 conferred protection against DPN in a Chinese population but was associated with higher DR risk in an Indian study, suggesting that the same allele may play distinct roles depending on ethnic background and clinical phenotype. Conclusions: VEGF signaling pathway genetic polymorphisms demonstrate potential as biomarkers for diabetic complications, especially microvascular outcomes. The findings suggest a genetic basis for differences in complications of T2DM. Future studies should investigate relevant SNPs across diverse ethnic groups to better understand genetic risks associated with the disease and its vascular complications. Full article

Overexpression of growth factor receptors and immunosuppressive molecules is a hallmark of many tumour cells, distinguishing them from normal tissue. This co-expression enables tumours both to exploit proliferative signalling and to evade immune surveillance. Here, we propose a strategy that employs a combination of monoclonal antibodies (mAbs) targeting two distinct antigens (Ags) at sub-cytotoxic doses. This approach aims to achieve a threshold cytotoxic density of immune complexes selectively on malignant cells expressing both target Ags, while sparing normal cells that express only one. Typically, the first target Ag may be a growth factor receptor, such as epidermal growth factor receptor (EGFR and HER1), epidermal growth factor receptor 2 (HER2), or vascular endothelial growth factor receptor 2 (VEGFR2), and the second, an immunoinhibitory molecule, such as programmed death-ligand 1 (PD-L1). Selective mAb-mediated tumour destruction is expected to enhance neoantigen (NeoAg) presentation to the immune system, while the blockade of PD-1/PD-L1 interactions should further stimulate anti-tumour immune responses. Notably, this strategy can be implemented using clinically approved therapeutic mAbs, potentially enabling rapid translation into clinical practice without extensive regulatory hurdles. Full article

Zebrafish are model organisms for drug screening owing to their transparent bodies, rapid embryonic development, and genetic similarities with humans. However, using standard polystyrene culture plates can limit the oxygen supply, potentially affecting embryo survival and the reliability of assays conducted in zebrafish. In this study, we evaluated the application of a novel, highly oxygen-permeable culture plate (InnoCell^TM) in zebrafish development and drug screening assays. Under both normal and oxygen-restricted conditions, zebrafish embryos cultured on InnoCell^TM plates exhibited significantly improved developmental parameters, including heart rate and body length, compared with those cultured on conventional polystyrene plates. The InnoCell^TM plate enabled a significant reduction in medium volume without compromising zebrafish embryo viability, thereby demonstrating its advantages, particularly in high-throughput 384-well formats. Drug screening tests using antiangiogenic receptor tyrosine kinase inhibitors (TKIs) revealed enhanced sensitivity and more pronounced biological effects in InnoCell^TM plates, as evidenced by the quantification of intersegmental blood vessels and gene expression analysis of the vascular endothelial growth factor receptor (vegfr, also known as kdrl). These results indicate that the InnoCell^TM highly oxygen-permeable plate markedly improves zebrafish-based drug screening efficiency and assay reliability, highlighting its potential for widespread application in biomedical research. Full article

Natural products, characterized by their structural novelty, multi-target capabilities, and favorable toxicity profiles, represent a prominent reservoir for the discovery of innovative anticancer therapeutics. In the current investigation, we identified ajuforrestin A, a diterpenoid compound extracted from Ajuga lupulina Maxim, as a potent agent against lung cancer. In vitro, this compound markedly curtailed the proliferation of A549 cells. Mechanistic explorations revealed that ajuforrestin A could arrest A549 cells in the G0/G1 phase of the cell cycle, provoke apoptosis in cancer cells, and impede their migration by modulating the STAT3 and FAK signaling cascades. Angiogenesis is indispensable for tumor formation, progression, and metastatic dissemination. Vascular endothelial growth factor (VEGF) and its receptor VEGFR-2 are established as crucial mediators in tumor neovascularization, a process fundamental to both the expansion of tumor cells and the development of new blood vessels within the tumor milieu. Through the combined application of a Tg(fli1:EGFP) zebrafish model and SPR experimentation, we furnished strong evidence for the ability of ajuforrestin A to obstruct tumor angiogenesis via selective engagement with VEGFR-2. Finally, a zebrafish xenograft tumor model demonstrated that ajuforrestin A could effectively restrain tumor growth and metastasis in vivo. Ajuforrestin A therefore shows considerable promise as a lead compound for the future development of therapies against non-small cell lung cancer (NSCLC). Full article

Background: Chronic wounds pose a significant public health challenge due to high treatment costs and the limited efficacy of current therapies. This study aims to evaluate the in vitro wound-healing activity and in silico interactions of two antimicrobial cationic peptides, derived from Galleria mellonella cecropin D, whose receptors are involved in tissue healing. Methods: Two peptides were tested: a long peptide (∆M2, 39 amino acids) and a short peptide (CAMP-CecD, 18 amino acids). Their cytotoxicity, as well as their effects on fibroblast proliferation and migration, were assessed using Detroit 551 cells. In parallel, molecular docking studies were conducted with AutoDock Vina to predict the binding affinities of these peptides to the key receptors involved in wound healing: the epidermal growth factor receptor (EGFR), the transforming growth factor beta receptor (TGFRβ2), and the vascular endothelial growth factor receptor (VEGFR). Results: In vitro assays showed that the short peptide exhibited lower cytotoxicity and significantly enhanced cell proliferation and migration, leading to a greater percentage of gap closure compared to the long peptide. A docking analysis revealed binding affinities of −6.7, −7.2, and −5.6 kcal/mol for VEGFR, EGFR, and TGFRβ2, respectively, with the RMSD values below 2 Å, indicating stable binding interactions. Conclusions: These findings suggest that the structure and cationic charge of the short peptide facilitate robust interactions with growth factor receptors, enhancing re-epithelialization and tissue regeneration. Consequently, this peptide is a promising candidate ligand for the treatment of chronic wounds and associated infections. Full article