Vascular Endothelial Growth Factor Receptor Research Articles

TMVP1448, a novel peptide improves detection of primary tumors and metastases by specifically targeting VEGFR-3

Lymphangiogenesis at primary tumor and draining lymph nodes plays a pivotal role in tumor metastasis, which has been demonstrated to be regulated by the vascular endothelial growth factor receptor 3 (VEGFR-3) pathway. However, the effect of molecular imaging peptides, which specifically bind VEGFR-3, in tracing tumors remains unclear. We prepared a novel peptide, TMVP1448, with high-affinity to VEGFR-3. The dissociation constant (KD) of TMVP1448 with VEGFR-3 was 7.07 ×10‐7 M. In vitro cellular assay showed that TMVP1448 could bind specifically with VEGFR-3. Near infrared imaging results showed that Cy7-TMVP1448 was able to accurately trace primary and metastatic cancers, and PET/CT results showed that [68Ga]Ga-DOTA-TMVP1448 was superior to commonly used radiotracers 18F-FDG. Additionally, no significant negative effect of TMVP1448 was found in mice. Our results suggested that TMVP1448 had great potential for future clinical applications in fluorescence imaging and nuclear imaging of tumors.

Single-arm study of camrelizumab plus apatinib for patients with advanced mucosal melanoma

BackgroundPrevious studies have suggested the potential synergistic antitumor activity when combining immune checkpoint inhibitors with anti-angiogenic agents in various solid tumors. We aimed to assess the efficacy and safety of...

From Deep Learning to the Discovery of Promising VEGFR-2 Inhibitors.

Vascular endothelial growth factor receptor 2 (VEGFR-2) stands as a prominent therapeutic target in oncology, playing a critical role in angiogenesis, tumor growth, and metastasis. FDA-approved VEGFR-2 inhibitors are associated with diverse side effects. Thus, finding novel and more effective inhibitors is of utmost importance. In this study, a deep learning (DL) classification model was first developed and then employed to select putative active VEGFR-2 inhibitors from an in-house chemical library including 187 druglike compounds. A pool of 18 promising candidates was shortlisted and screened against VEGFR-2 by using molecular docking. Finally, two compounds, RHE-334 and EA-11, were prioritized as promising VEGFR-2 inhibitors by employing PLATO, our target fishing and bioactivity prediction platform. Based on this rationale, we prepared RHE-334 and EA-11 and successfully tested their anti-proliferative potential against MCF-7 human breast cancer cells with IC50 values of 26.78±4.02 and 38.73±3.84 μM, respectively. Their toxicities were instead challenged against the WI-38. Interestingly, expression studies indicated that, in the presence of RHE-334, VEGFR-2 was equal to 0.52±0.03, thus comparable to imatinib equal to 0.63±0.03. In conclusion, this workflow based on theoretical and experimental approaches demonstrates effective in identifying VEGFR-2 inhibitors and can be easily adapted to other medicinal chemistry goals.

Design, synthesis, in vitro, and in silico studies of new thiadiazol derivatives as promising VEGFR-2 inhibitors and apoptosis inducers

The presented study reports the synthesis, in silico and in vitro evaluations of a series of novel thiadiazole derivatives designed with the pharmacophoric features of Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) inhibitors. A comprehensive assessment against MCF-7 and HepG2 cancer cell lines revealed promising inhibitors, particularly, N-(4-((E)-1-(((Z)-5-acetyl-3-(2-chlorophenyl)-1,3,4-thiadiazol-2(3H)-ylidene) hydrazono) ethyl) phenyl)-4-chlorobenzamide (compound 22) exhibited a significantly low half-maximal inhibitory concentration (IC50) value against both MCF-7 and HepG2 cells of 0.03 µM and 0.39 µM, respectively. The rest of compounds exhibited also significant IC50 values against MCF-7 and HepG2 cells of (0.07–4.7 µM) and (0.12–8.75 µM), respectively. Furthermore, compound 22 displayed a VEGFR-2 inhibitory activity (VEGFR-2 = 0.042 µM) comparable to the established inhibitor sorafenib (VEGFR-2 = 0.041 µM). Detailed cell cycle analysis demonstrated that compound 22 induced a G0-G1 phase arrest of the MCF-7 cells (71.33 %), indicative of its potential to modulate cell cycle progression. Notably, compound 22 also exhibited a substantial increase in apoptosis in the MCF-7 cells, particularly in early (22.04 %) and late stages (13.94 %), underscoring its remarkable pro-apoptotic effect. Additionally, Compound 22 demonstrated a notable decrease in the migratory ability and wound healing capacity of MCF-7 cells. Computational studies, including molecular docking, revealed high binding affinities. Over a 200 ns MD simulation, the VEGFR-2-compound 22 complex initially displayed a rapid increase in RMSD followed by stability around 3.5 Å due to ligand conformational change while maintaining stable protein binding. This was confirmed by RMSF, SASA, RoG, and hydrogen bonding analysis. MM-GBSA, ProLIF, PCAT and FEL studies confirmed VEGFR-2-compound 22 complex binding at both dynamic and energetic levels. The computational ADMET studies demonstrated favorable pharmacokinetic properties. Furthermore, Density Functional Theory (DFT) studies confirmed the reactivity and stability of compound 22. These comprehensive findings underscore the potential of compound 22 as a lead candidate for further investigation in the development of VEGFR-2-targeted anticancer agents.

Suppression of pathological neovascularization by anti-Flt1 peptide functionalized DNA tetrahedron

Angiogenesis is an important and necessary process in tissue regeneration and recovery, but suppressing such process is also a critical therapeutic consideration in some diseases including tumor and corneal neovascularization. Currently, pathological angiogenesis is mainly inhibited through the blockade of the interaction between vascular endothelial growth factor receptor (VEGFR) and its ligands. Compared to traditional anti-angiogenic agents such as monoclonal antibody and tyrosine kinase inhibitor, polypeptide has gained growing interests for high unit activity, few adverse reactions, and low costs. Among them, anti-Flt1 (AF) peptide could inhibit VEGFR1-induced endothelial cell migration and tube formation, showing excellent anti-angiogenic activity. Addressing the issues of low water solubility, instability, and poor bioavailability would significantly hinder the applications of AF. Herein, we prepared an AF functionalized tetrahedral framework nucleic acid (tFNA@AF) to overcome the abovementioned limitations of AF. The tFNA@AF presented enhanced structural stability and cellular uptake of AF, and exhibited superior bioavailability and satisfying anti-angiogenic effectiveness in vitro. Furthermore, tFNA@AF also demonstrated high-efficiency pathological angiogenesis inhibition on tumor-bearing mice of triple-negative breast cancer and corneal neovascularization of cornea cauterized rats, two typical models of tumor and traumatic cornea where angiogenesis is not anticipant. Our tFNA@AF as a novel polypeptide-nucleic acid conjugated nanomaterials showed superior bioavailability and high anti-angiogenic effectiveness, suggesting that with incremental improvements the nanomedicine may offer potentially useful treatment aid for anti-angiogenic therapy to prevent tumor growth and corneal neovascularization.

A senescence-mimicking (senomimetic) VEGFR TKI side-effect primes tumor immune responses via IFN/STING signaling.

Tyrosine kinase inhibitors (TKIs) that block the vascular endothelial growth factor receptors (VEGFRs) disrupt tumor angiogenesis but also have many unexpected side-effects that impact tumor cells directly. This includes the induction of molecular markers associated with senescence, a form of cellular aging that typically involves growth arrest. We have shown that VEGFR TKIs can hijack these aging programs by transiently inducting senescence-markers (SMs) in tumor cells to activate senescence-associated secretory programs that fuel drug resistance. Here we show that these same senescence-mimicking ('senomimetic') VEGFR TKI effects drive an enhanced immunogenic signaling that, in turn, can alter tumor response to immunotherapy. Using a live-cell sorting method to detect beta-galactosidase, a commonly used SM, we found that subpopulations of SM-expressing (SM+) tumor cells have heightened interferon (IFN) signaling and increased expression of IFN-stimulated genes (ISGs). These ISG increases were under the control of the STimulator of INterferon Gene (STING) signaling pathway, which we found could be directly activated by several VEGFR TKIs. TKI-induced SM+ cells could stimulate or suppress CD8 T-cell activation depending on host:tumor cell contact while tumors grown from SM+ cells were more sensitive to PD-L1 inhibition in vivo, suggesting that offsetting immune-suppressive functions of SM+ cells can improve TKI efficacy overall. Our findings may explain why some (but not all) VEGFR TKIs improve outcomes when combined with immunotherapy and suggest that exploiting senomimetic drug side-effects may help identify TKIs that uniquely 'prime' tumors for enhanced sensitivity to PD-L1 targeted agents.

The Alzheimer's disease-linked protease BACE2 cleaves VEGFR3 and modulates its signaling.

The β-secretase β-site APP cleaving enzyme (BACE1) is a central drug target for Alzheimer's disease. Clinically tested, BACE1-directed inhibitors also block the homologous protease BACE2. Yet little is known about physiological BACE2 substrates and functions in vivo. Here, we identify BACE2 as the protease shedding the lymphangiogenic vascular endothelial growth factor receptor 3 (VEGFR3). Inactivation of BACE2, but not BACE1, inhibited shedding of VEGFR3 from primary human lymphatic endothelial cells (LECs) and reduced release of the shed, soluble VEGFR3 (sVEGFR3) ectodomain into the blood of mice, nonhuman primates, and humans. Functionally, BACE2 inactivation increased full-length VEGFR3 and enhanced VEGFR3 signaling in LECs and also in vivo in zebrafish, where enhanced migration of LECs was observed. Thus, this study identifies BACE2 as a modulator of lymphangiogenic VEGFR3 signaling and demonstrates the utility of sVEGFR3 as a pharmacodynamic plasma marker for BACE2 activity in vivo, a prerequisite for developing BACE1-selective inhibitors for safer prevention of Alzheimer's disease.

NFS-11. PHASE II STUDY OF AXITINIB IN PATIENTS WITH NEUROFIBROMATOSIS TYPE 2-RELATED SCHWANNOMATOSIS AND PROGRESSIVE VESTIBULAR SCHWANNOMAS

Abstract BACKGROUND Axitinib is an oral multi-receptor tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor (VEGFR), platelet derived growth factor receptor (PDGFR), and c-KIT. These represent a clinically and/or preclinically validated molecular targets in vestibular schwannoma (VS). METHODS Eligible participants were age >5 years with a clinical diagnosis of neurofibromatosis type 2-related schwannomatosis (NF2-SWN) and at least one volumetrically measurable, progressive VS. Axitinib was given continuously in 28-day cycles for up to of 12 cycles. Primary endpoint was objective volumetric response rate to axitinib, hearing response was a secondary endpoint, along with validated quality of life assessments (NFTI-QOL). RESULTS Twelve participants were enrolled and eight completed 12 cycles, including two pediatric patients. Two patients were non-evaluable due to coming off study prior to the first scheduled response evaluation: one withdrew from the study for personal reasons and one for non-compliance. Due to slowing accrual, the study closed prior to meeting planned enrollment of 17 evaluable patients. Ten patients were evaluable for the primary endpoint, defined as ≥20% decrease in VS volume, with two volumetric responses observed; both were reached after three cycles and sustained during treatment. Best volumetric response was −53.9% after nine cycles. Hearing response was evaluable in nine participants, with three hearing responses observed, one of which was sustained during treatment. All participants experienced drug-related toxicities, the most common were diarrhea, hematuria and skin toxicity, not exceeding grade 2, as well as hypertension, not exceeding grade 3. NFTI-QOL scores remained stable or improved during treatment in all participants. CONCLUSIONS Axitinib therapy targeting VEGFR, PDGFR and c-KIT is feasible in this population and associated with volumetric and hearing responses in a subset of patients. The convenience of oral administration appears to be offset, however, by increased toxicity and lower response rates compared to VEGF-A targeted therapy with bevacizumab.

Expression of vascular endothelial growth factor receptor in thymic epithelial tumors

Expression of vascular endothelial growth factor receptor in thymic epithelial tumors

Anti-angiogenic and antioxidant effects of axitinib in human retinal endothelial cells: implications in diabetic retinopathy.

Diabetic retinopathy is a secondary microvascular complication of diabetes mellitus. This disease progresses from two stages, non-proliferative and proliferative diabetic retinopathy, the latter characterized by retinal abnormal angiogenesis. Pharmacological management of retinal angiogenesis employs expensive and invasive intravitreal injections of biologic drugs (anti-vascular endothelial growth factor agents). To search small molecules able to act as anti-angiogenic agents, we focused our study on axitinib, which is a tyrosine kinase inhibitor and represents the second line treatment for renal cell carcinoma. Axitinib is an inhibitor of vascular endothelial growth factor receptors, and among the others tyrosine kinase inhibitors (sunitinib and sorafenib) is the most selective towards vascular endothelial growth factor receptors 1 and 2. Besides the well-known anti-angiogenic and immune-modulatory functions, we hereby explored the polypharmacological profile of axitinib, through a bioinformatic/molecular modeling approach and in vitro models of diabetic retinopathy. We showed the anti-angiogenic activity of axitinib in two different in vitro models of diabetic retinopathy, by challenging retinal endothelial cells with high glucose concentration (fluctuating and non-fluctuating). We found that axitinib, along with inhibition of vascular endothelial growth factor receptors 1 (1.82 ± 0.10; 0.54 ± 0.13, phosphorylated protein levels in fluctuating high glucose vs . axitinib 1 µM, respectively) and vascular endothelial growth factor receptors 2 (2.38 ± 0.21; 0.98 ± 0.20, phosphorylated protein levels in fluctuating high glucose vs . axitinib 1 µM, respectively), was able to significantly reduce (p < 0.05) the expression of Nrf2 (1.43 ± 0.04; 0.85 ± 0.01, protein levels in fluctuating high glucose vs . axitinib 1 µM, respectively) in retinal endothelial cells exposed to high glucose, through predicted Keap1 interaction and activation of melanocortin receptor 1. Furthermore, axitinib treatment significantly (p < 0.05) decreased reactive oxygen species production (0.90 ± 0.10; 0.44 ± 0.06, fluorescence units in high glucose vs . axitinib 1 µM, respectively) and inhibited ERK pathway (1.64 ± 0.09; 0.73 ± 0.06, phosphorylated protein levels in fluctuating high glucose vs . axitinib 1 µM, respectively) in HRECs exposed to high glucose. The obtained results about the emerging polypharmacological profile support the hypothesis that axitinib could be a valid candidate to handle diabetic retinopathy, with ancillary mechanisms of action.

The protective effects of Axitinib on blood-brain barrier dysfunction and ischemia-reperfusion injury in acute ischemic stroke

Background and purposeThe pathophysiological features of acute ischemic stroke (AIS) often involve dysfunction of the blood-brain barrier (BBB), characterized by the degradation of tight junction proteins (Tjs) leading to increased permeability. This dysfunction can exacerbate cerebral injury and contribute to severe complications. The permeability of the BBB fluctuates during different stages of AIS and is influenced by various factors. Developing effective therapies to restore BBB function remains a significant challenge in AIS treatment. High levels of vascular endothelial growth factor (VEGF) in the early stages of AIS have been shown to worsen BBB breakdown and stroke progression. Our study aimed to investigate the protective effects of the VEGF receptor inhibitor Axitinib on BBB dysfunction and cerebral ischemia/reperfusion-induced injury. MethodsBEnd3 cell exposed to oxygen–glucose deprivation (OGD) model was constructed to estimate pharmacological activity of Axitinib (400 ng/ml) on anti-apoptosis and pathological barrier function recovery. In vivo, rats were subjected to a 1 h transient middle cerebral artery occlusion and 23 h reperfusion (tMCAO/R) to investigate the permeability of BBB and cerebral tissue damage. Axitinib was administered through the tail vein at the beginning of reperfusion. BBB integrity was assessed by Evans blue leakage and the expression levels of Tjs claudin-5 and occludin. ResultsOur research revealed that co-incubation with Axitinib enhanced the cell viability of OGD-insulted bEnd3 cells, decreased LDH leakage rate, and suppressed the expression of apoptosis-related proteins cytochrome C and Bax. Axitinib also mitigated the damage to Tjs and facilitated the restoration of transepithelial electrical resistance in OGD-insulted bEnd.3 cells. In vivo, Axitinib administration reduced intracerebral Evans blue leakage and up-regulated the expression of Tjs in the penumbra brain tissue in tMCAO/R rats. Notably, 10 mg/kg Axitinib exerted a significant anti-ischemic effect by decreasing cerebral infarct volume and brain edema volume, improving neurological function, and reducing pro-inflammatory cytokines IL-6 and TNF-α in the brain. ConclusionsOur study highlights Axitinib as a potent protectant of blood-brain barrier function, capable of promoting pathological blood-brain barrier recovery through VEGF inhibition and increased expression of tight junction proteins in AIS. This suggests that VEGF antagonism within the first 24 h post-stroke could be a novel therapeutic approach to enhance blood-brain barrier function and mitigate ischemia-reperfusion injury.

Disease-Modifying Effects of Lenvatinib, a Multiple Receptor Tyrosine Kinase Inhibitor, on Posttraumatic Osteoarthritis of the Knee.

Angiogenesis and vascular endothelial growth factor (VEGF) are involved in osteoarthritis (OA). We previously reported the inhibitory effect of bevacizumab in a rabbit model of OA. In the current study, we investigated the effects of lenvatinib, an angiogenesis inhibitor targeting the VEGF and fibroblast growth factor receptors, on synovitis, osteophyte formation, and cartilage degeneration in a rabbit OA model. Posttraumatic OA was induced by anterior cruciate ligament transection (ACLT) on one knee of each rabbit. Rabbits were placed into four groups according to the following lenvatinib doses: untreated control (n = 12), L0.3: 0.3 mg/kg/day (n = 15), L1.0: 1.0 mg/kg/day (n = 14), and L3.0: 3.0 mg/kg/day (n = 13) groups. We evaluated limb pain using the weight distribution ratio measured with an incapacitance tester, macroscopic osteophyte formation, and femoral condyle synovium and cartilage histology. For cartilage evaluation, the following distal sites of the femur were evaluated separately: femoral-tibial (FT), femoral-patellar (FP), and femoral corner (between FP and FT). The weight distribution ratio at 12 weeks after surgery was higher in the L0.3 and L1.0 groups than in the control group. Osteophyte formation and synovitis scores were significantly lower in the L0.3, L1.0, and L3.0 groups than in the control group. The Osteoarthritis Research Society International scores of the FT, corner, and FP sites in the L0.3 group were lower than in the control group. The cartilage thickness ratio at the FT and corner sites was significantly lower in the L0.3 group than in the control group. Krenn's grading system of cartilage synovitis showed that all lenvatinib-administered groups had significantly lower scores than the control group. MMP3 expression level in cartilage tissue was significantly lower in the L3.0 group compared with the other three groups. ADAMTS5 expression was lower in the L3.0 group compared with the control and L0.3 groups. Oral administration of lenvatinib inhibited synovitis, osteophyte formation, and cartilage degeneration and reduced pain in a rabbit ACLT model. Lenvatinib is an oral VEGF inhibitor that is easier to administer than other VEGF inhibitors and may have potential as a treatment of posttraumatic OA.

The incidence of drug-induced interstitial lung disease caused by epidermal growth factor receptor tyrosine kinase inhibitors or immune checkpoint inhibitors in patients with non-small cell lung cancer in presence and absence of vascular endothelial growth factor inhibitors: a systematic review.

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=409534, identifier CRD42023409534.

Characteristics of Retinal Vascular Degeneration and the Expression of Vessel-Related Claudin Proteins in Retinal Degeneration Mouse.

This study aimed to investigate the characteristics of retinal vascular degeneration and the expression of vessel-related claudin (CLD) proteins in retinal degeneration mouse (Pde6βrd1/rd1 rd1 mouse). Retinas from wild-type (WT) mice and rd1 mice at postnatal day 3 (P3), P5, P8, P11, P13, P15, P18, and P21 were collected. Immunofluorescence staining was used to assess the retinal vascular plexus, cell proliferation, CLD expression, and retinal ganglion cells (RGCs). The distribution of retinal superficial and deep vessels was determined by isolectin B4 fluorescence staining of retinal flat mounts and frozen sections. Hematoxylin and eosin staining and terminal deoxynucleotidyl transferase-mediated dNTP nick-end labeling were used to investigate retinal histological degeneration and apoptosis in rd1 mice, respectively. Quantitative real-time PCR and Western blot were used to measure the expression of vessel-related CLD-1, -2, -3, and -5, vascular endothelial growth factor A (VEGFA), and vascular endothelial growth factor receptor 2 (VEGFR2) in the retinas. Compared to the WT mice, the rd1 mice displayed delayed but completed progressive development in the retinal superficial vascular plexuses (SVPs) and deep vascular plexuses (DVPs). In the rd1 mice, the thickness of retinal layers gradually decreased and the retinas underwent progressive atrophy and degeneration. The deterioration got worse at the late developmental stage. The declined vessel density of SVP and DVP correlated with the decreased thickness of the full and inner parts of the retina and the reduced number of RGCs. DVP degeneration and the thinning of the outer nuclear layer exhibited an obvious reduction at P15. The expression levels of CLD-1, CLD-2, CLD-3, CLD-5, VEGFA, and VEGFR2 decreased and were consistently lower in the rd1 mice than in WT mice since P15. Rd1 mice exhibited progressive vascular degeneration of retinal SVP and DVP, the thinning and atrophy of retinal ONL and RGC, and the downregulation of vessel-related CLD proteins during the late developmental period. Thus, the rd1 mouse is a useful model of not only retinal neuro-degeneration but also retinal vascular degeneration.

Potential inhibitors of VEGFR1, VEGFR2, and VEGFR3 developed through Deep Learning for the treatment of Cervical Cancer

Cervical cancer stands as a prevalent gynaecologic malignancy affecting women globally, often linked to persistent human papillomavirus infection. Biomarkers associated with cervical cancer, including VEGF-A, VEGF-B, VEGF-C, VEGF-D, and VEGF-E, show upregulation and are linked to angiogenesis and lymphangiogenesis. This research aims to employ in-silico methods to target tyrosine kinase receptor proteins—VEGFR-1, VEGFR-2, and VEGFR-3, and identify novel inhibitors for Vascular Endothelial Growth Factors receptors (VEGFRs). A comprehensive literary study was conducted which identified 26 established inhibitors for VEGFR-1, VEGFR-2, and VEGFR-3 receptor proteins. Compounds with high-affinity scores, including PubChem ID—25102847, 369976, and 208908 were chosen from pre-existing compounds for creating Deep Learning-based models. RD-Kit, a Deep learning algorithm, was used to generate 43 million compounds for VEGFR-1, VEGFR-2, and VEGFR-3 targets. Molecular docking studies were conducted on the top 10 molecules for each target to validate the receptor-ligand binding affinity. The results of Molecular Docking indicated that PubChem IDs—71465,645 and 11152946 exhibited strong affinity, designating them as the most efficient molecules. To further investigate their potential, a Molecular Dynamics Simulation was performed to assess conformational stability, and a pharmacophore analysis was also conducted for indoctrinating interactions.

Molecular Docking and Dynamic Simulation of Erythrina fusca Lour Chemical Compounds Targeting VEGFR-2 Receptor for Anti-Liver Cancer Activity

Liver cancer is a serious health concern characterized by abnormal cell growth, but currently, available treatment options are limited, suggesting the need for a new therapeutic method. Therefore, this research aimed to investigate the potential of chemical compounds obtained from the cangkring plant (Erythrina fusca) as anti-liver cancer agents targeting Vascular Endothelial Growth Factor Receptor 2 (VEGFR-2). The investigation was conducted in silico through molecular docking and dynamic method. Molecular docking was performed using AutoDock Tools, followed by visualization with Biovia Discovery Studio. Additionally, molecular dynamics simulation was conducted using GROMACS software and visualized with Grace. A total of 36 chemical compounds from E. fusca were used as ligands for molecular docking. The results showed that Isobavachalcone (ISB) was the most effective test compound with a binding energy of -11.45 kcal/mol, compared to the positive control Sorafenib with a value of - 11.51 kcal/mol. In this context, hydrogen bonding, as well as hydrophobic, electrostatic, and unfavorable molecular interactions were identified. Moreover, molecular dynamics simulation provided RMSD, RMSF, Radius of Gyration (Rg), and hydrogen bond parameters. Analysis of these parameters further confirmed the superior stability of ISB in binding to VEGFR-2, suggesting the potential to suppress angiogenesis by blocking the receptor.

IL-6 Polymorphism as a Predisposing Genetic Factor for Gestational Diabetes or Preeclampsia Development in Pregnancy with Obesity in Relation to VEGF and VEGFF Receptor Gene Expression Modalities.

The increased prevalence of obesity worldwide has been implicated in the alarming rise of the incidence of gestational diabetes and preeclampsia, which are both considered threatening conditions for both mother and fetus. We studied gene polymorphisms of the proinflammatory cytokine Interleukin 6 (IL-6) and the gene expression levels of VEGF (vascular endothelial growth factor) and VEGF-R (endothelial growth factor receptor), all known to be involved in pregnancy complications, aiming to identify possible predisposing risk factors in pregnancies with obesity. The G allele of IL-6 was found to correspond with an increased risk for gestational diabetes and preeclampsia occurrence. Furthermore, in obese pregnant mothers with either gestational diabetes or pre-existing type 2 diabetes and those who developed preeclampsia, it was confirmed that gene expression levels of VEGF were reduced while they were increased for VEGF receptors. We conclude that the genetic profile of an obese pregnant woman shares a common background with that of a patient with pre-existing type 2 diabetes mellitus, and therefore predisposes them to complications in pregnancy.

Enhancing guided bone regeneration with cross-linked collagen-conjugated xenogeneic bone blocks and membrane fixation: A preclinical invivo study.

To determine whether combining cross-linked (CL) collagen-integrated xenogeneic bone blocks stabilized with the fixation of resorbable collagen membranes (CM) can enhance guided bone regeneration (GBR) in the overaugmented calvarial defect model. Four circular defects with a diameter of 8 mm were prepared in the calvarium of 13 rabbits. Defects were randomly assigned to receive one of the following treatments: (i) non-cross-linked (NCL) porcine-derived collagen-embedded bone block covered by a CM without fixation (NCL + unfix group); (ii) NCL bone block covered by CM with fixation using bone-tack (NCL + fix group); (iii) cross-linked (CL) porcine-derived collagen-embedded bone block covered by CM without fixation (CL + unfix group); and (iv) CL bone block covered by CM with fixation using bone-tack fixation (CL + fix group). The efficacy of GBR was assessed through histological and molecular analyses after 2 and 8 weeks. At 2 weeks, there were no significant differences in histologically measured areas of newly formed bone among the groups. At 8 weeks, however, the CL + fix group exhibited a larger area of new bone (5.08 ± 1.09 mm2, mean ± standard deviation) compared to the NCL + unfix (1.62 ± 0.42 mm2; p < .0083), NCL + fix (3.97 ± 1.39 mm2) and CL + unfix (2.55 ± 1.04 mm2) groups. Additionally, the expression levels of tumour necrosis factor-alpha, fibroblast growth factor-2, vascular endothelial growth factor, osteocalcin and calcitonin receptor were significantly higher in the CL + fix group compared to the other three groups (p < .0083). Cross-linked bone blocks stabilized with collagen membrane fixation can significantly enhance GBR.

Vorolanib, sunitinib, and axitinib: A comparative study of vascular endothelial growth factor receptor inhibitors and their anti-angiogenic effects.

Pathological angiogenesis and vascular instability are observed in diabetic retinopathy (DR), diabetic macular edema (DME), and wet age-related macular degeneration (wAMD). Many receptor tyrosine kinases (RTKs) including vascular endothelial growth factor receptors (VEGFRs) contribute to angiogenesis, whereas the RTK TIE2 is important for vascular stability. Pan-VEGFR tyrosine kinase inhibitors (TKIs) such as vorolanib, sunitinib, and axitinib are of therapeutic interest over current antibody treatments that target only one or two ligands. This study compared the anti-angiogenic potential of these TKIs. A kinase HotSpot™ assay was conducted to identify TKIs inhibiting RTKs associated with angiogenesis and vascular stability. Half-maximal inhibitory concentration (IC50) for VEGFRs and TIE2 was determined for each TKI. In vitro angiogenesis inhibition was investigated using a human umbilical vein endothelial cell sprouting assay, and in vivo angiogenesis was studied using the chorioallantoic membrane assay. Melanin binding was assessed using a melanin-binding assay. Computer modeling was conducted to understand the TIE2-axitinib complex as well as interactions between vorolanib and VEGFRs. Vorolanib, sunitinib, and axitinib inhibited RTKs of interest in angiogenesis and exhibited pan-VEGFR inhibition. HotSpot™ assay and TIE2 IC50 values showed that only axitinib potently inhibited TIE2 (up to 89%). All three TKIs effectively inhibited angiogenesis in vitro. In vivo, TKIs were more effective at inhibiting VEGF-induced angiogenesis than the anti-VEGF antibody bevacizumab. Of the three TKIs, only sunitinib bound melanin. TKIs differ in their classification and binding to VEGFRs, which is important because type II inhibitors have greater selectivity than type I TKIs. Vorolanib, sunitinib, and axitinib exhibited pan-VEGFR inhibition and inhibited RTKs associated with pathological angiogenesis. Of the three TKIs, only axitinib potently inhibited TIE2 which is an undesired trait as TIE2 is essential for vascular stability. The findings support the use of vorolanib for therapeutic inhibition of angiogenesis observed in DR, DME, and wAMD.

Triple negative breast cancer cells exposed to aryl hydrocarbon receptor ligands hexachlorobenzene and chlorpyrifos activate endothelial cells

Breast cancer is currently one of the most prevalent cancers worldwide. The mechanisms by which pesticides can increase breast cancer risk are multiple and complex. We have previously observed that two aryl hydrocarbon receptor (AhR) agonists ‒pesticides hexachlorobenzene (HCB) and chlorpyrifos (CPF)‒ act on tumor progression, stimulating cell migration and invasion in vitro and tumor growth in animal models. Elevated levels of hypoxia inducible factor-1α (HIF-1α) are found in malignant breast tumors, and HIF-1α is known to induce proangiogenic factors such as vascular endothelial growth factor (VEGF), nitric oxide synthase-2 (NOS-2) and cyclooxygenase-2 (COX-2), which are fundamental in breast cancer progression. In this work, we studied HCB (0.005, 0.05, 0.5 and 5 μM) and CPF (0.05, 0.5, 5 and 50 μM) action on the expression of these proangiogenic factors in triple negative breast cancer cells MDA-MB-231, as well as the effect of their conditioned medium (CM) on endothelial cells. Exposure to pesticides increased HIF-1α and VEGF protein expression in an AhR-dependent manner. In addition, HCB and CPF boosted NOS-2 and COX-2 content and VEGF secretion in MDA-MB-231 cells. The treatment of endothelial cells with CM from tumor cells exposed to pesticides increased cell proliferation, migration, and tubule formation, enhancing both tubule length and branching points. Of note, these effects were VEGF-dependent, as they were blocked in the presence of a VEGF receptor-2 (VEGFR-2) inhibitor. In sum, our results highlight the harmful impact of HCB and CPF in modulating the interaction between breast cancer and endothelial cells and promoting angiogenesis.