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Thiazole and its derivatives have received a lot of attention from researchers due to its wide biological, pharmacological, and anticancer properties. A novel series of 2-[2-[4-Hydroxy-3-substituted benzylidene hydrazinyl]-thiazole-4[5H]-ones (4a–c) and acetoxy derivative (5) were synthesized via using thiosemicarbazones (2a–c). The structure of the thiazole derivatives (4a–c) and 5 in these compounds was confirmed by spectroscopic techniques (IR and NMR), as well as elemental investigations. The synthesized derivatives biological activity was assessed based on their capacity to suppress the growth of the cancer cell lines MCF-7 and HepG2, as well as to halt the cell cycle and trigger apoptosis. Among the synthesized thiazole derivatives, compound 4c was found the most active derivative, with inhibitory concentrations IC50 = 2.57 ± 0.16 and 7.26 ± 0.44 µM in MCF-7 and HepG2, respectively, compared to Staurosporine as the standard drug with IC50 6.77 ± 0.41 and 8.4 ± 0.51 µM, respectively. Additionally, compound 4c blocked vesicular endothelial growth factor receptor-2 (VEGFR-2), according to our results (IC50 = 0.15 µM), compared to Sorafenib (IC50 = 0.059 µM) as the standard drug. Moreover, compound 4c induced cell cycle arrest at the G1/S phase, increasing the percentage and accumulation of cancer cells (DNA content) in the pre-G1 phase by 37.36% in MCF-7 cancer cells compared to untreated MCF-7 cells at 2.02%. Also, compound 4c increased the percentage of early and late apoptosis from 0.51% and 0.29%, respectively, in the case of the MCF-7 untreated control sample to 22.39% and 9.51%, respectively, in the MCF-7 treated sample. Furthermore, molecular docking studies of compounds 4a–c and 5 were conducted with four key proteins (aromatase, epidermal growth factor receptor (EGFR), cyclin-dependent kinase 2 (CDK2), and B-cell lymphoma 2 (Bcl-2)) that stimulate the growth, proliferation, and development of cancer cells. Compound 4c exhibited good docking scores with a promising and potential binding affinity toward the active site of selected docked proteins. According to these results, compound 4c showed efficient cytotoxic activity against the tested cancer cells. [ABSTRACT FROM AUTHOR]

Haemangiomas (HAs) are prevalent vascular endothelial cell tumours. With respect to the possible involvement of HIF‐1α in HAs, we have explored its role in haemangioma endothelial cell (HemEC) proliferation and apoptosis. shRNA HIF‐1α and pcDNA3.1 HIF‐α were manipulated into HemECs. HIF‐α, VEGF, and VEGFR‐2 mRNA and protein levels were assessed by qRT‐PCR and Western blotting. Cell proliferation and viability, cell cycle and apoptosis, migration and invasion, and ability to form tubular structures were assessed by colony formation assay, CCK‐8, flow cytometry, Transwell assay, and tube formation assay. Cell cycle‐related protein levels, and VEGF and VEGFR‐2 protein interaction were detected by Western blot and immunoprecipitation assays. An Haemangioma nude mouse model was established by subcutaneous injection of HemECs. Ki67 expression was determined by immunohistochemical staining. HIF‐1α silencing suppressed HemEC neoplastic behaviour and promoted apoptosis. HIF‐1α facilitated VEGF/VEGFR‐2 expression and the VEGF had interacted with VEGFR‐2 at protein ‐ protein level. HIF‐1α silencing arrested HemECs at G0/G1 phase, diminished Cyclin D1 protein level, and elevated p53 protein level. VEGF overexpression partially abrogated the effects of HIF‐1α knockdown on inhibiting HemEC malignant behaviours. Inhibiting HIF‐1α in nude mice with HAs repressed tumour growth and Ki67‐positive cells. Briefly, HIF‐1α regulated HemEC cell cycle through VEGF/VEGFR‐2, thus promoting cell proliferation and inhibiting apoptosis. [ABSTRACT FROM AUTHOR]

A computer‐assisted drug design (CADD) approach was utilized to design a new acetamido‐N‐(para‐fluorophenyl)benzamide) derivative of the naturally occurring alkaloid, theobromine, (T‐1‐APFPB), following the pharmacophoric features of VEGFR‐2 inhibitors. The stability and reactivity of T‐1‐AFPB were assessed through density functional theory (DFT) calculations. Molecular docking assessments showed T‐1‐AFPB's potential to bind with and inhibit VEGFR‐2. The precise binding of T‐1‐AFPB against VEGFR‐2 with optimal energy was further confirmed through several molecular dynamics (MD) simulations, PLIP, MM‐GBSA, and PCA studies. Then, T‐1‐AFPB (4‐(2‐(3,7‐Dimethyl‐2,6‐dioxo‐2,3,6,7‐tetrahydro‐1H‐purin‐1‐yl)acetamido)‐N‐(4‐fluorophenyl)benzamide) was semi‐synthesized and the in vitro assays showed its potential to inhibit VEGFR‐2 with an IC50 value of 69 nM (sorafenib's IC50 was 56 nM) and to inhibit the growth of HepG2 and MCF‐7 cancer cell lines with IC50 values of 2.24±0.02 and 3.26±0.02 μM, respectively. Moreover, T‐1‐AFPB displayed very high selectivity indices against normal Vero cell lines. Furthermore, T‐1‐AFPB induced early (from 0.72 to 19.12) and late (from 0.13 to 6.37) apoptosis in HepG2 cell lines. In conclusion, the combined computational and experimental approaches demonstrated the efficacy and safety of T‐1‐APFPB providing it as a promising lead VEGFR‐2 inhibitor for further development aiming at cancer therapy. [ABSTRACT FROM AUTHOR]

Metastasis, the dissemination of tumor cells, stands as the second most prominent contributor to mortality arising from breast cancer. To counteract this phenomenon, the molecular markers associated with angiogenesis, particularly vascular endothelial growth factor (VEGF) and its receptor (VEGFR), have emerged as promising strategies for impeding the progression of tumor cells. Compounds like pyrimidines, coumarins, oxadiazoles, and triazoles have undergone comprehensive investigations due to their notable anticancer potential, highlighting their encouraging capacities in inhibiting VEGFR-2, an essential mediator of angiogenesis signaling. Herein, we have synthesized pyrimidine–triazoles and oxadiazole–triazoles using electrochemical and conventional methods. The newly synthesized compounds were evaluated for anticancer activity against MCF-7 breast cancer cells, and it was found that the compounds 8a and 8b showed IC50 values of 5.29 and 15.54 μM, respectively. Our in silico mode of action revealed that these compounds could target VEGFR-2, which was further evidenced by our in silico structure-based bioinformatic analysis. In conclusion, we reported an electrochemical method to prepare novel drug-like compounds, based on triazole and other heterocyclic hybrids, that could be used to design VGFR-targeting drugs. [ABSTRACT FROM AUTHOR]

Abstract Background The vascular endothelial growth factor receptor-2 (VEGFR-2) plays an important role in melanoma development and progression. Peptide vaccines have shown great potential in cancer immunotherapy by targeting VEGFR-2 as a tumor-associated antigen and boosting the immune response against both tumor cells and tumor endothelial cells. Despite this, the low efficiency of peptide vaccines has resulted in moderate therapeutic results in the majority of studies. Enhancing the delivery of peptide vaccines using nanoliposomes is an important strategy for improving the efficacy of peptide vaccines. In this regard, we designed VEGFR-2-derived peptides restricted to both mouse MHC I and human HLA-A*02:01 using immunoinformatic tools and selected three peptides representing the highest binding affinities. The peptides were encapsulated in nanoliposomal formulations using the film method plus bath sonication and characterized for their colloidal properties. Results The mean diameter of peptide-encapsulated liposomes was around 135 nm, zeta potential of − 17 mV, and encapsulation efficiency of approximately 70%. Then, vaccine formulations were injected subcutaneously in mice bearing B16F10-established melanoma tumors and their efficiency in triggering immunological, and anti-tumor responses was evaluated. Our results represented that one of our designed VEGFR-2 peptide nanoliposomal formulations (Lip-V1) substantially activated CD4+ (p

This retrospective case–control study examined the association between the rs2071559 (-604T/C) single nucleotide polymorphism (SNP) in the vascular endothelial growth factor receptor (VEGFR)-2 gene and the risk of diabetic retinopathy (DR) in Northern Han Chinese. This study included patients diagnosed with diabetes mellitus (DM) in Shijiazhuang between 07/2014 and 07/2016. The healthy controls were unrelated individuals who received routine physical examinations. The diabetic patients were grouped as DM (diabetes but no fundus examination abnormalities), proliferative DR (PDR), and non-proliferative DR (NPDR). Finally, 438 patients were included: 114 controls and 123, 105, and 96 patients in the DM, NPDR, and PDR groups, respectively. In the multivariable analyses and all genetic models, the VEGFR-2 rs2071559 SNP was not associated with DR (among all diabetic patients) or with PDR (among the patients with DR) after adjustment for age, sex, duration of DM, blood glucose, systolic blood pressure, diastolic blood pressure, and body mass index (all P > 0.05). In conclusion, the VEGFR-2- 604T/C rs2071559 SNP is not associated with DR or PDR in the Han Chinese population of Shijiazhuang (China).

Background and objectives: Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) inhibition results in an increase in apoptosis. It has been demonstrated that NF-κB subunit p65 phosphorylation at the IκB kinase phosphorylation site serine 536 (Ser536) is essential for the NF-κB nuclear translocation and activation. Therefore, NF-κB can be downregulated by suppressing its phosphorylation. The vascular endothelial growth factor receptor-2 (VEGFR-2) suppression could result in apoptosis induction. Therefore, targeting these pathways via VEGFR-2 inhibitors might have therapeutic potential for cancer treatment. It has been indicated that an antagonist peptide of VEGF, referred to as VGB3, could neutralize and recognize VEGFR2 in the tumoral and endothelial cells. This study aimed to induce apoptosis in human umbilical vein endothelial cells (HUVEC) cells through the inhibition of these signaling pathways. Methods: Effects of different concentrations of VGB3 (1-200 ng/ml) were evaluated on the viability of HUVEC cells using MTT assay. In addition, downstream signaling pathways in HUVE cells were evaluated through quantitative assessment of protein expression via western blotting. Results: The results demonstrated that VGB3 treatment inhibited the growth of HUVEC cells. Moreover, Bcl-2 was decreased in the cells treated with the VGB3 compared to the control. Furthermore, VGB3 significantly enhanced the cleaved-caspase7 levels, which is an indicator of apoptosis progression. Altogether, VGB3 enhanced apoptosis in HUVEC cells. Conclusion: Our results indicate that the peptide might be a potential candidate for antitumor therapy via inhibiting the NF-κB pathway.

More people are being diagnosed with resistant breast cancer, increasing the urgency of developing new effective treatments. Several lines of evidence suggest that blocking the kinase activity of VEGFR-2 reduces angiogenesis and slows tumor growth. In this study, we developed novel VEGFR-2 inhibitors based on the triazolopyrazine template by using comparative molecular field analysis (CoMFA) and molecular similarity indices (CoMSIA) models for 3D-QSAR analysis of 23 triazolopyrazine-based compounds against breast cancer cell lines (MCF -7). Both CoMFA (Q2 = 0.575; R2 = 0.936, Rpred2 = 0.956) and CoMSIA/SE (Q2 = 0.575; R2 = 0.936, Rpred2 = 0.847) results demonstrate the robustness and stability of the constructed model. Six novel compounds with potent inhibitory activity were carefully designed, and screening of ADMET properties revealed their good oral bioavailability and ability to diffuse through various biological barriers. When compared with the most active molecule in the data set and with Foretinib (breast cancer drug), molecular docking revealed that the six designed compounds had strengthened affinity (−8.9 to −10 kcal/mol) to VEGFR-2. Molecular Dynamics Simulations and MMPBSA calculations were applied to the selected compound T01 with the highest predicted inhibitory activity, confirming its stability in the active pocket of VEGFR-2 over 100 ns. The present results provided the basis for the chemical synthesis of new compounds with improved inhibitory properties against the breast cancer cell line (MCF -7).

A series of 1,3‐disubstituted‐2‐thioxoimidazolidin‐4‐one and diazine derivatives were synthesized and confirmed through IR, NMR, and mass spectrometry. The in vitro cytotoxic activity of synthesized compounds against HePG2 and MCF‐7 cells were assessed by MTT assay. Furthermore, Aromatase, VEGFR‐2, B‐Raf, cell cycle, Annexin V, caspase‐3 and sulphatase expression by PCR, and β‐catenin expression by western blot were estimated. The results revealed that the synthesized compounds possess cytotoxic activity against HePG2 and MCF‐7 cell lines. Compound 11 (2,2′‐(1E,1′E)‐1,1′‐(hydrazine‐1,2‐diylidene) bis (ethan‐1‐yl‐1‐ylidene) bis (4‐(phenyldiazenyl) phenol) had greater cytotoxic activity than staurosporine (6.24 μg/mL), with IC50 of 2.55 μg/mL against HepG2 cells and (4.21 μg/mL) against MCF‐7 cells. Moreover, the inhibitory activity against aromatase was (0.156 μg/mL), (0.23 μg/mL) against VEGFR2, and (0.25 μg/mL) against B‐Raf. Also, this compound decreased DNA content of HepG2 cells in the S phase and the G2/M phase, and increased the apoptosis in Annexin measurement. By real‐time PCR, This compound up‐regulated the expression of caspase‐3 in HepG2 cells, reduced the expression of sulphatase gene in HepG2 cells, and reduced β‐catenin expression in HepG2 by western blot analysis. Consequently, the synthesized derivatives could be a promising scaffold for the development of potent anti‐cancer agents due to their apoptotic and anti‐inflammatory activities. [ABSTRACT FROM AUTHOR]

New Zn(II), Cd(II), VO(IV), and UO2(VI) solvatochromic complexes derived from 6‐ethyl‐4‐hydroxy‐2,5‐dioxo‐5,6‐dihydro‐2H‐pyrano[3,2‐c]quinoline‐3‐carboxaldehyde‐semicarbazone ligand (H2L) were synthesized and established by elemental analyses, spectral (IR, UV, NMR, mass spectra), molar conductivity measurements, magnetic susceptibility, and thermal gravimetric analysis (TGA). The ligand coordinates with metal ions through ONO chelating sites, forming an octahedral geometry arrangement, except UO2(VI) that showed pentagonal bipyramidal geometry. Using Coats–Redfern methodology, the kinetic parameters (Ea, A, ΔH, ΔS, and ΔG) of the thermal decomposition steps were calculated and discussed. The complexes showed solvatochromic behavior that used to estimate the ground and excited state dipole moments. Optimization and structural parameters were carried out by density function theory (DFT) at B3LYP/GENECP method at 6‐311G(d,p) basis set for C, H, N, and O atoms and SDD (Stuttgart/Dresden) basis set for the metal atoms and interrelated with the experimental results. The complexes were tested for antimicrobial efficiency against Gram‐positive bacteria, Gram‐negative bacteria, yeast, and fungi. Also, antitumor activity was investigated against HepG‐2 cell line. Finally, the new synthesized complexes upon subjecting to molecular docking and distinguishable results showed outstanding inhibition results of VEGFR‐2 via achieving a high stabilization level inside the largest pocket of 1YWN protein. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factors (VEGFs) are specific cytokines involved in angiogenesis and do so via binding to vascular endothelial growth factor receptors (VEGFRs), a type of receptor tyrosine kinase. VEGFs are reported to facilitate angiogenesis in physiological (embryogenesis) and pathological (tumor) conditions. The overexpression of VEGFs and consequently VEGFRs is reported in tumorigenic conditions. Several VEGFR inhibitors currently used as anticancer drugs to prevent angiogenesis are sunitinib, sorafenib, etc. To identify new potential candidates as VEGFR inhibitors, a classification study using a large and diverse dataset of VEGFR inhibitors from the BindingDB database has been conducted. The KNIME platform was used to calculate molecular and fingerprint‐based descriptors and several classification algorithms viz. linear regression (LR), k‐nearest neighbor (kNN), decision tree (DT), random forest (RF), and gradient boosted tree (GBT) were employed to build the classification model. The model performance was evaluated by accuracy, precision, recall, and F1 score of the test set. The best LR, kNN, DT, RF, and GBT classifiers had the F1 score of 0.81, 0.87, 0.82, 0.87, and 0.87, respectively. The assorted 5120 VEGFR inhibitors were clustered into 10 subsets, and the structural features of each subset were assessed along with the identification of significant fragments in active and inactive compounds. The automated classifier model developed using the KNIME platform could serve as an important platform for screening and designing molecules as VEGFR inhibitors. [ABSTRACT FROM AUTHOR]

Based on quinazoline, quinoxaline, and nitrobenzene scaffolds and on pharmacophoric features of VEGFR-2 inhibitors, 17 novel compounds were designed and synthesised. VEGFR-2 IC50 values ranged from 60.00 to 123.85 nM for the new derivatives compared to 54.00 nM for sorafenib. Compounds 15a, 15b, and 15d showed IC50 from 17.39 to 47.10 µM against human cancer cell lines; hepatocellular carcinoma (HepG2), prostate cancer (PC3), and breast cancer (MCF-7). Meanwhile, the first in terms of VEGFR-2 inhibition was compound 15d which came second with regard to antitumor assay with IC50 = 24.10, 40.90, and 33.40 µM against aforementioned cell lines, respectively. Furthermore, Compound 15d increased apoptosis rate of HepG2 from 1.20 to 12.46% as it significantly increased levels of Caspase-3, BAX, and P53 from 49.6274, 40.62, and 42.84 to 561.427, 395.04, and 415.027 pg/mL, respectively. Moreover, 15d showed IC50 of 253 and 381 nM against HER2 and FGFR, respectively.

New quinoline and isatin derivatives having the main characteristics of VEGFR-2 inhibitors was synthesised. The antiproliferative effects of these compounds were estimated against A549, Caco-2, HepG2, and MDA-MB-231. Compounds 13 and 14 showed comparable activities with doxorubicin against the Caco-2 cells. These compounds strongly inhibited VEGFR-2 kinase activity. The cytotoxic activities were evaluated against Vero cells. Compound 7 showed the highest value of safety and selectivity. Cell migration assay displayed the ability of compound 7 to prevent healing and migration abilities in the cancer cells. Furthermore, compound 7 induced apoptosis in Caco-2 through the expressive down-regulation of the apoptotic genes, Bcl2, Bcl-xl, and Survivin, and the upregulation of the TGF gene. Molecular docking against VEGFR-2 emerged the interactions of the synthesised compounds in a similar way to sorafenib. Additionally, seven molecular dynamics simulations studies were applied and confirmed the stability of compound 13 in the active pocket of VEGFR-2 over 100 ns.

In this study, a set of novel benzoxazole derivatives were designed, synthesised, and biologically evaluated as potential VEGFR-2 inhibitors. Five compounds (12d, 12f, 12i, 12l, and 13a) displayed high growth inhibitory activities against HepG2 and MCF-7 cell lines and were further investigated for their VEGFR-2 inhibitory activities. The most potent anti-proliferative member 12 l (IC50 = 10.50 μM and 15.21 μM against HepG2 and MCF-7, respectively) had the most promising VEGFR-2 inhibitory activity (IC50 = 97.38 nM). A further biological evaluation revealed that compound 12l could arrest the HepG2 cell growth mainly at the Pre-G1 and G1 phases. Furthermore, compound 12l could induce apoptosis in HepG2 cells by 35.13%. likely, compound 12l exhibited a significant elevation in caspase-3 level (2.98-fold) and BAX (3.40-fold), and a significant reduction in Bcl-2 level (2.12-fold). Finally, docking studies indicated that 12l exhibited interactions with the key amino acids in a similar way to sorafenib.

Background/purpose: Vascular endothelial growth factor receptor (VEGFR) expression in oral squamous cell carcinoma (OSCC) promotes tumor growth through both autocrine and paracrine signaling. VEGF-positive OSCC cases are associated with a high depth of invasion, increased metastasis, and poor prognosis. In this study we established and then molecularly and functionally analyzed an OSCC cell line that co-expresses VEGF-A, VEGFR-1, and VEGFR-2, termed HCM-SqCC010 cells. Materials and methods: VEGF-A, VEGFR-1, and VEGFR-2 expression in HCM-SqCC010 cells were examined by immunohistochemistry and immunoblotting. Expression and inhibition of VEGF-A, VEGFR-1, and VEGFR-2 in HCM-SqCC010 cells were verified by quantitative real-time PCR. Results: Our analysis of HCM-SqCC010 cells revealed that their proliferation depended on VEGF-A, and selective inhibition of VEGFR-1 or VEGFR-2 resulted in decreased cell growth. Conclusion: We established an OSCC cell line, HCM-SqCC010, that expresses VEGF-A, VEGFR-1, and VEGFR-2. This triple-positive cell line showed no effect from a molecular targeted drug toward VEGF-A, but it did show strong cell growth inhibition in response to a VEGFR inhibitor. Thus, new therapeutic strategies against OSCC should include a VEGFR inhibitor.

To investigate the effect of Apatinib (an inhibitor targeting VEGFR‐2) enhances chemosensitivity of ABT‐199 on diffuse large B‐cell lymphoma (DLBCL). Viability assay and flow cytometric assay for determining apoptosis, cell cycle, mitochondrial membrane potential, reactive oxygen species and immunoblotting were used to explore the combination effect in DLBCL cell lines, DLBCL patient samples, and DLBCL mouse models. RNA sequencing assay helped identify mechanisms of ABT‐199 plus Apatinib. The results show that ABT‐199 combined with Apatinib inhibited cell proliferation, reduced colony‐forming capacity, and induced apoptosis and cell cycle arrest in DLBCL cells. Mechanistically, the combination therapy inhibited tumour cell growth and promoted tumour cell death by regulating EDN1 and MAPK‐related pathways and activating the intrinsic apoptotic pathway. The effect of the combination therapy was also validated in primary DLBCL blasts and xenograft mouse models. Our findings indicate that Apatinib enhances the chemosensitivity of ABT‐199 and might serve as a promising therapeutic strategy for DLBCL.

Vascular endothelial growth factors (VEGFs) are important regulators of angiogenesis, neuroprotection, and neurogenesis. Studies have indicated the association of VEGF dysregulation with the development of neurodegenerative and cerebrovascular diseases. We studied the changes in serum levels of VEGF-A, VEGFR-1, and VEGFR-2 in patients at various phases of ischemic and hemorrhagic strokes. Quantitative assessment of VEGF-A, VEGFR-1, and VEGFR-2 in serum of patients with hemorrhagic or ischemic stroke was performed by enzyme immunoassay in the hyper-acute (1–24 h from the onset), acute (up to 1–7 days), and early subacute (7 days to 3 months) phases of stroke, and then compared with the control group and each other. Results of our retrospective study demonstrated different levels of VEGF-A and its receptors at various phases of ischemic and hemorrhagic strokes. In ischemic stroke, increased VEGFR-2 level was found in the hyper-acute (p = 0.045) and acute phases (p = 0.024), while elevated VEGF-A and reduced VEGFR-1 levels were revealed in the early subacute phase (p = 0.048 and p = 0.012, respectively). In hemorrhagic stroke, no significant changes in levels of VEGF-A and its receptors were identified in the hyper-acute phase. In the acute and early subacute phases there was an increase in levels of VEGF-A (p < 0.001 and p = 0.006, respectively) and VEGFR-2 (p < 0.001 and p = 0.012, respectively). Serum levels of VEGF-A and its receptors in patients with hemorrhagic and ischemic stroke indicate different pathogenic pathways depending on the phase of the disease.

Background: The vascular endothelial growth factor receptor-2 (VEGFR-2) plays an important role in melanoma development and progression. Peptide vaccines have shown great potential in cancer immunotherapy by targeting VEGFR-2 as a tumor-associated antigen and boosting the immune response against both tumor cells and tumor endothelial cells. Despite this, the low efficiency of peptide vaccines has resulted in moderate therapeutic results in the majority of studies. Enhancing the delivery of peptide vaccines using nanoliposomes is an important strategy for improving the efficacy of peptide vaccines. In this regard, we designed VEGFR-2-derived peptides restricted to both mouse MHC I and human HLA-A*02:01 using immunoinformatic tools and selected three peptides representing the highest binding affinities. The peptides were encapsulated in nanoliposomal formulations using the film method plus bath sonication and characterized for their colloidal properties. Results: The mean diameter of peptide-encapsulated liposomes was around 135 nm, zeta potential of − 17 mV, and encapsulation efficiency of approximately 70%. Then, vaccine formulations were injected subcutaneously in mice bearing B16F10-established melanoma tumors and their efficiency in triggering immunological, and anti-tumor responses was evaluated. Our results represented that one of our designed VEGFR-2 peptide nanoliposomal formulations (Lip-V1) substantially activated CD4+ (p < 0.0001) and CD8+ (P < 0.001) T cell responses and significantly boosted the production of IFN-γ (P < 0.0001) and IL-4 (P < 0.0001). Furthermore, this formulation led to a significant decrease in tumor volume (P < 0.0001) and enhanced survival (P < 0.05) in mice. Conclusion: Our findings suggest that the nanoliposomal formulation containing VEGFR-2 peptides could be a promising therapeutic vaccination approach capable of eliciting strong antigen-specific immunologic and anti-tumor responses. [ABSTRACT FROM AUTHOR]

This work focuses on the development of thirteen benzylethylenearyl ureas and one carbamate. After the synthesis and purification of the compounds, we studied their antiproliferative action on cell lines, such as HEK-293, and cancer ones, such as HT-29, MCF-7 or A-549, on the immune Jurkat T-cells and endothelial cells HMEC-1. Compounds C.1, C.3, C.12 and C.14 were selected for further biological studies to establish their potential as immunomodulating agents. Some of the derivatives exhibited significant inhibitory effects on both targets: PD-L1 and VEGFR-2 in the HT-29 cell line, showing that urea C.12 is active against both targets. Some compounds could inhibit more than 50% of cancer cell proliferation compared to non-treated ones when assessed in co-cultures using HT-29 and THP-1 cells. In addition, they significantly reduced CD11b expression, which is a promising target for immune modulation in anticancer immunotherapies. [ABSTRACT FROM AUTHOR]

Objective: Angiogenesis is indeed a vital process in the progression of carcinomas, including that of larynx. Therefore, this study (AngLaC) aimed to identify candidate angiogenesis‐related biomarkers in laryngeal carcinoma patients. Study Design: Prospective controlled cohort study. Setting: Tertiary referral center. Methods: In silico analyses of angiogenesis‐related genes in laryngeal carcinoma were performed to determine candidate biomarkers. Serum levels of candidate biomarkers were determined via enzyme‐linked immunosorbent assay in laryngeal carcinoma patients as well as in an age and gender‐matched control group. The associations of the biomarkers with clinical parameters were investigated. Results: The study included 60 laryngeal carcinoma patients and 20 healthy controls. The serum levels of osteopontin, IGFBP‐3, VEGF, sVEGFR‐1, and VEGFR‐2 were significantly higher in the patient group (p <.001, p ≤.001, p <.001, p <.01, p <.01, respectively). High osteopontin and sVEGFR‐1 levels were associated with locoregional‐recurrence (p =.024, p =.016, respectively). IGFBP‐3 had the highest diagnostic sensitivity (81.4%) and specificity (80%) among the molecules that were investigated (p <.001). High sVEGFR‐1 and low VEGFR‐2 levels were associated with poor overall‐survival (p =.037, p =.027, respectively). High osteopontin and sVEGFR‐1 levels were associated with poor disease‐specific survival rates (p =.035, p =.018, respectively). Conclusion: High serum levels of sVEGFR‐1 and osteopontin as well as low serum levels of VEGFR‐2 proved to be poor prognostic in terms of survival in laryngeal carcinoma. VEGF, sVEGFR1, VEGFR2, IGFBP‐3, and osteopontin levels were found to be significantly increased in larynx cancer patients compared to the normal population. Further studies on osteopontin and sVEGFR‐1 are required in order to determine their associations with recurrence. [ABSTRACT FROM AUTHOR]

The high vascularization of glioma highlights the potential value of anti-angiogenic therapeutics for glioma treatment. Previously, we designed a novel vascular-targeting and blood–brain barrier (BBB)-penetrating peptide, TAT-AT7, by attaching the cell-penetrating peptide TAT to a vascular-targeting peptide AT7, and we demonstrated that TAT-AT7 could target binding to the vascular endothelial growth factor receptor 2 (VEGFR-2) and Neuropilin-1 (NRP-1), which are both highly expressed in endothelial cells. TAT-AT7 has been proven to be a good targeting peptide which could effectively deliver the secretory endostatin gene to treat glioma via the TAT-AT7-modified polyethyleneimine (PEI) nanocomplex. In the current study, we further explored the molecular binding mechanisms of TAT-AT7 to VEGFR-2 and NRP-1 and its anti-glioma effects. Accordingly, TAT-AT7 was proven to competitively bind to VEGFR-2 and NRP-1 and prevent VEGF-A165 binding to the receptors by the surface plasmon resonance (SPR) assay. TAT-AT7 inhibited endothelial cells' proliferation, migration, invasion, and tubule formation, as well as promoted endothelial cells' apoptosis in vitro. Further research revealed that TAT-AT7 inhibited the phosphorylation of VEGFR-2 and its downstream PLC-γ, ERK1/2, SRC, AKT, and FAK kinases. Additionally, TAT-AT7 significantly inhibited angiogenesis of zebrafish embryo. Moreover, TAT-AT7 had a better penetrating ability and could penetrate the BBB into glioma tissue and target glioma neovascularization in an orthotopic U87-glioma-bearing nude mice model, and exhibited the effect of inhibiting glioma growth and angiogenesis. Taken together, the binding and function mechanisms of TAT-AT7 were firstly revealed, and TAT-AT7 was proven to be an effective and promising peptide for the development of anti-angiogenic drugs for targeted treatment of glioma. [ABSTRACT FROM AUTHOR]

Thirteen benzylethoxyaryl ureas have been synthesized and biologically evaluated as multitarget inhibitors of VEGFR-2 and PD-L1 proteins to overcome resistance phenomena offered by cancer. The antiproliferative activity of these molecules on several tumor cell lines (HT-29 and A549), on the endothelial cell line HMEC-1, on immune cells (Jurkat T) and on the non-tumor cell line HEK-293 has been determined. Selective indexes (SI) have been also determined and compounds bearing p-substituted phenyl urea unit together with a diaryl carbamate exhibited high SI values. Further studies on these selected compounds to determine their potential as small molecule immune potentiators (SMIPs) and as antitumor agents have been performed. From these studies, we have concluded that the designed ureas have good tumor antiangiogenic properties, exhibit good inhibition of CD11b expression, and regulate pathways involved in CD8 T-cell activity. These properties suggest that these compounds could be potentially useful in the development of new cancer immune treatments. [ABSTRACT FROM AUTHOR]

A series of coumarin derivatives were designed, synthesized, and evaluated for their antiproliferative activity. Compound 3e exhibited significant antiproliferative activity and was further evaluated at five doses at the National Cancer Institute. It effectively inhibited vascular endothelial growth factor receptor‐2 (VEGFR‐2) with an IC50 value of 0.082 ± 0.004 µM compared with sorafenib. While compound 3e significantly downregulated total VEGFR‐2 and its phosphorylation, it markedly reduced the HUVEC's migratory potential, resulting in a significant disruption in wound healing. Furthermore, compound 3e caused a 22.51‐fold increment in total apoptotic level in leukemia cell line HL‐60(TB) and a 6.91‐fold increase in the caspase‐3 level. Compound 3e also caused cell cycle arrest, mostly at the G1/S phase. Antibacterial activity was evaluated against Gram‐positive and Gram‐negative bacterial strains. Compound 3b was the most active derivative, with the same minimum inhibitory concentration and minimum bactericidal concentration value of 128 μg/mL against K. pneumonia and high stability in mammalian plasma. Moreover, compounds 3b and 3f inhibited Gram‐negative DNA gyrase with IC50 = 0.73 ± 0.05 and 1.13 ± 0.07 µM, respectively, compared to novobiocin with an IC50 value of 0.17 ± 0.02 µM. The binding affinity and pattern of derivative 3e toward the VEGFR‐2 active site and compounds 3a–c and 3f in the DNA gyrase active site were evaluated using molecular modeling. Overall, ADME studies of the synthesized coumarin derivatives displayed promising pharmacokinetic properties. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor (VEGF) exerts neuroprotective or proinflammatory effects, depending on what VEGF forms (A–E), receptor types (VEGFR1–3), and intracellular signaling pathways are involved. Neonatal monosodium glutamate (MSG) treatment triggers neuronal death by excitotoxicity, which is commonly involved in different neurological disorders, including neurodegenerative diseases. This study was designed to evaluate the effects of VEGFR‐2 inhibition on neuronal damage triggered by excitotoxicity in the cerebral motor cortex (CMC) and hippocampus (Hp) after neonatal MSG treatment. MSG was administered at a dose of 4 g/kg of body weight (b.w.) subcutaneously on postnatal days (PD) 1, 3, 5, and 7, whereas the VEGFR‐2 inhibitor SU5416 was administered at a dose of 10 mg/kg b.w. subcutaneously on PD 5 and 7, 30 min before the MSG treatment. Neuronal damage was assessed using hematoxylin and eosin staining, fluoro‐Jade staining, and TUNEL assay. Additionally, western blot assays for some proteins of the VEGF‐A/VEGFR‐2 signaling pathway (VEGF‐A, VEGFR‐2, PI3K, Akt, and iNOS) were carried out. All assays were performed on PD 6, 8, 10, and 14. Inhibition of VEGFR‐2 signaling by SU5416 increases the neuronal damage induced by neonatal MSG treatment in both the CMC and Hp. Moreover, neonatal MSG treatment increased the expression levels of the studied VEGF‐A/VEGFR‐2 signaling pathway proteins, particularly in the CMC. We conclude that VEGF‐A/VEGFR‐2 signaling pathway activation could be part of the neuroprotective mechanisms that attempt to compensate for neuronal damage induced by neonatal MSG treatment and possibly also in other conditions involving excitotoxicity. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor receptor‐2 (VEGFR‐2) is crucial in promoting tumor angiogenesis and cancer metastasis. Thus, inhibition of VEGFR‐2 has appeared as a good tactic for cancer treatment. To find out novel VEGFR‐2 inhibitors, first, the PDB structure of VEGFR‐2, 6GQO, was selected based on atomic nonlocal environment assessment (ANOLEA) and PROCHECK assessment. 6GQO was then further used for structure‐based virtual screening (SBVS) of different molecular databases, including US‐FDA approved drugs, US‐FDA withdrawn drugs, may bridge, MDPI, and Specs databases using Glide. Based on SBVS, receptor fit, drug‐like filters, and absorption, distribution, metabolism, excretion, and toxicity (ADMET) analysis of 427877 compounds, the best 22 hits were selected. From the 22 hits, hit 5 complex with 6GQO was put through molecular mechanics/generalized born surface area (MM/GBSA) study and hERG binding. The MM/GBSA study revealed that hit 5 possesses lesser binding free energy with more inferior stability in the receptor pocket than the reference compound. The VEGFR‐2 inhibition assay of hit 5 disclosed an IC50 of 165.23 nM against VEGFR‐2, which can be possibly enhanced through structural modifications. [ABSTRACT FROM AUTHOR]

Acetylsalicylic acid (ASA) is a well-established drug for heart attack and stroke prophylaxis. Furthermore, numerous studies have reported an anti-carcinogenic effect, but its exact mechanism is still unknown. Here, we applied VEGFR-2-targeted molecular ultrasound to explore a potential inhibitory effect of ASA on tumor angiogenesis in vivo. Daily ASA or placebo therapy was performed in a 4T1 tumor mouse model. During therapy, ultrasound scans were performed using nonspecific microbubbles (CEUS) to determine the relative intratumoral blood volume (rBV) and VEGFR-2-targeted microbubbles to assess angiogenesis. Finally, vessel density and VEGFR-2 expression were assessed histologically. CEUS indicated a decreasing rBV in both groups over time. VEGFR-2 expression increased in both groups up to Day 7. Towards Day 11, the binding of VEGFR-2-specific microbubbles further increased in controls, but significantly (p = 0.0015) decreased under ASA therapy (2.24 ± 0.46 au vs. 0.54 ± 0.55 au). Immunofluorescence showed a tendency towards lower vessel density under ASA and confirmed the result of molecular ultrasound. Molecular US demonstrated an inhibitory effect of ASA on VEGFR-2 expression accompanied by a tendency towards lower vessel density. Thus, this study suggests the inhibition of angiogenesis via VEGFR-2 downregulation as one of the anti-tumor effects of ASA. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma (RCC) is the most fatal tumor in the urinary system. Resistance development and unmet effective responses, request new anticancer agents with better therapeutic index. Ten new imino-thiazolo-quinoxaline derivatives (5a-j) were synthesized and preliminary evaluated for downregulation of Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) activity taking sorafenib as a reference drug. Compounds 5d & 5h showed potent inhibition to VEGFR-2 activity at IC50 89.35 nM & 60.64 nM, respectively, then they both were further evaluated in-vitro against urinary bladder cancer cell line T-24 taking sorafenib as a reference drug. Compound 5h displayed nearly anticancer activity to sorafenib against T-24 cell line in all concentrations tested except at concentration 10 µM where it highly suppressed cell viability to 6.71 % compared to 15.15% of sorafenib. Compound 5h was then evaluated for its ameliorative efect against radiation induced renal tissue injury. Assessment of pro-angiogenic (VEGFR-2), pro-fibrotic (transforming growth factor-beta 1 (TGF-β1)) and apoptotic (caspase-3) markers, as well as histopathological examinations were performed on kidney of irradiated mice. Results showed ability of compound 5h to downregulate VEGFR-2 activity and its cytotoxic effect against RCC, in addition to mitigation of radiation induced renal tissue injury. Ethyl imino-thiazoloquinoxaline carboxylate derivative 5h showed a potential cytotoxic activity against RCC and could be considered a promosing alleviative candidate when employed post radiotherapy regimen. [ABSTRACT FROM AUTHOR]

• A new series of vatalanib analogs based on quinoxaline has been designed, synthesized, and biologically evaluated as anticancer candidates. • Cytotoxic activities were evaluated against HepG2 and HCT116 cell lines. • In vitro VEGFR-2 inhibitory activity, cell cycle and apoptosis rate were evaluated for the most promising candidate. • Molecular docking and in silico ADMET study studies were carried out for the synthesized compounds. In our attempts to improve pharmacokinetics and pharmacodynamics characters of vatalanib, four strategies of the drug design were applied to design and synthesis new quinoxaline based vatalanib analogs. Antiproliferative activities of the synthesized compounds were investigated against two tumor cell lines (HepG2 and HCT‐116) using vatalanib as a positive control. The new candidates showed promising anticancer activity against two tested cancer cell lines with IC 50 values ranging from 6.04 ± 0.19 to 100.15 ± 3.26 µM, in particular compounds 11b and 11c which were more potent than vatalanib. The most potent was the 4-benzoylquinoxaline derivative 11b (IC 50 = 6.04 ± 0.19 µM and 15.58 ± 0.58 µM) compared to vatalanib (IC 50 of 25.27 ± 0.84 µM and 43.91 ± 1.64 µM) against HepG2 and HCT116, respectively. The selectivity indices of 11b were found to be approximately 14 and 5 towards HepG2 and HCT116, respectively. While vatalanib showed selectivity indices of about 5 and 3 towards HepG2 and HCT116, respectively. The most promising compound 11b was further investigated in HepG‐2 cells for its apoptotic effect, cell cycle arrest and in vitro VEGFR-2 inhibitory activity as the main mechanisms of cell death. It was found that 11b can induce apoptosis and arrest the cell cycle at the at G1 phase in addition to, compound 11b showed effective inhibition of VEGFR-2 with IC 50 of 0.918 ± 0.033 µM compared to vatalanib (IC 50 of 0.265 ± 0.009 µM). Deep computational studies were created for the designed compounds including molecular docking, physicochemical properties, profiling pharmacokinetics, ADMET studies, and toxicity predictions to evaluate the prospective drug candidates. The results of the docking study were consistent with biological testing, furthermore, in silico ADMET study revealed the superior pharmacokinetics characters of the new candidates over vatalanib. So, the current work suggests that the 4-benzoylquinoxaline-1-yl-acetamide derivatives, especially 11b, can serve as lead molecules for development of new effective anticancer drugs. [Display omitted] [ABSTRACT FROM AUTHOR]

The global prevalence of oral squamous cell carcinoma (OSCC) has been increasing. OSCC at the advanced stage tends to resist conventional treatment and causes local recurrence and distant metastasis, resulting in poor prognosis. Therefore, detecting this cancer at an early stage and performing early intervention are important. Promising biomarkers to detect OSCC have yet to be established; however, microRNAs (miRNAs/miRs) serve a crucial role in OSCC tumorigenesis and may be potential biomarkers. In the present case report, the availability of salivary miRNAs as a therapeutic and prognostic marker for patients with OSCC was assessed. The patient was a 33-year-old woman who was diagnosed with advanced OSCC of the tongue, and their miRNA profile isolated from a saliva sample at each clinical course was evaluated. Microarray analysis of the salivary samples revealed changes in the levels of four miRNAs (hsa-miR-6798-5p, miR-6803-5p, miR-6805-5p and miR-6845-5p) in accordance with the clinical course. Neoadjuvant chemotherapy and surgical procedure decreased the levels, whereas the levels increased when the patient was diagnosed with lung metastasis. Furthermore, tongue and lung metastatic lesion specimens exhibited expression of the vascular endothelial growth factor receptor-2, which is regulated by the four miRNAs. Accordingly, the present report proposed that salivary miRNAs could be a therapeutic and prognostic biomarker for OSCC. [ABSTRACT FROM AUTHOR]

Extracellular-signal-regulated kinase 5 (ERK5) is critical for normal cardiovascular development. Previous studies have defined a canonical pathway for ERK5 activation, showing that ligand stimulation leads to MEK5 activation resulting in dual phosphorylation of ERK5 on Thr218/Tyr220 residues within the activation loop. ERK5 then undergoes a conformational change, facilitating phosphorylation on residues in the C-terminal domain and translocation to the nucleus where it regulates MEF2 transcriptional activity. Our previous research into the importance of ERK5 in endothelial cells highlighted its role in VEGF-mediated tubular morphogenesis and cell survival, suggesting that ERK5 played a unique role in endothelial cells. Our current data show that in contrast to EGF-stimulated HeLa cells, VEGF-mediated ERK5 activation in human dermal microvascular endothelial cells (HDMECs) does not result in C-terminal phosphorylation of ERK5 and translocation to the nucleus, but instead to a more plasma membrane/cytoplasmic localisation. Furthermore, the use of small-molecule inhibitors to MEK5 and ERK5 shows that instead of regulating MEF2 activity, VEGF-mediated ERK5 is important for regulating AKT activity. Our data define a novel pathway for ERK5 activation in endothelial cells leading to cell survival. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the expression of several differentiation markers in the apical papilla (AP) and dental pulp (DP) of human permanent teeth. Twenty young human teeth were extracted and classified according to three Moorrees tooth development stages: initial root formation (Ri), root length ½ (R1/2), and root length complete (Rc). Immunohistochemical assays were performed using STRO-1, VEGF Receptor-2, Neurofilament heavy (NFH), and Nestin antibodies and analyzed under light microscopy. Decalcified, formalin fixed paraffin embedded tooth sections stained with hematoxylin and eosin showed an apical cell rich zone between the DP and AP. The AP revealed fewer vascular and cellular components than the DP. STRO-1 was expressed on vascular and neuronal elements beneath the odontoblast (OB) and in the sub-odontoblastic (SOB) zone, and VEGFR-2 positive cells were observed in the endothelium, arterioles, and blood vessels. Neuroepithelial stem cell protein (Nestin) was highly expressed in differentiated odontoblasts in the predentin odontotoblast and odontoblast cell processes. Neurofilament heavy (NFH) was expressed in mature axons throughout the DP. STRO-1 and VEGFR-2 microvascular expression was higher at the stages Ri and R1/2 while STRO-1 and NFH expression showed strong spatial distribution of Rc neuronal elements as compared to Ri and R1/2. Differentiated OB and SOB cells showed Nestin expression, indicating a reservoir of newly differentiated odontoblast-like cells. [ABSTRACT FROM AUTHOR]

Purpose: Hyperglycaemia-induced oxidative stress and inflammation contribute to vascular cell dysfunction and subsequent cardiovascular events in T2DM. Selective sodium-glucose co-transporter-2 (SGLT-2) inhibitor empagliflozin significantly improves cardiovascular mortality in T2DM patients (EMPA-REG trial). Since SGLT-2 is known to be expressed on cells other than the kidney cells, we investigated the potential ability of empagliflozin to regulate glucose transport and alleviate hyperglycaemia-induced dysfunction of these cells. Methods: Primary human monocytes were isolated from the peripheral blood of T2DM patients and healthy individuals. Primary human umbilical vein endothelial cells (HUVECs) and primary human coronary artery endothelial cells (HCAECs), and fetoplacental endothelial cells (HPECs) were used as the EC model cells. Cells were exposed to hyperglycaemic conditions in vitro in 40 ng/mL or 100 ng/mL empagliflozin. The expression levels of the relevant molecules were analysed by RT-qPCR and confirmed by FACS. Glucose uptake assays were carried out with a fluorescent derivative of glucose, 2-NBDG. Reactive oxygen species (ROS) accumulation was measured using the H2DFFDA method. Monocyte and endothelial cell chemotaxis were measured using modified Boyden chamber assays. Results: Both primary human monocytes and endothelial cells express SGLT-2. Hyperglycaemic conditions did not significantly alter the SGLT-2 levels in monocytes and ECs in vitro or in T2DM conditions. Glucose uptake assays carried out in the presence of GLUT inhibitors revealed that SGLT-2 inhibition very mildly, but not significantly, suppressed glucose uptake by monocytes and endothelial cells. However, we detected the significant suppression of hyperglycaemia-induced ROS accumulation in monocytes and ECs when empagliflozin was used to inhibit SGLT-2 function. Hyperglycaemic monocytes and endothelial cells readily exhibited impaired chemotaxis behaviour. The co-treatment with empagliflozin reversed the PlGF-1 resistance phenotype of hyperglycaemic monocytes. Similarly, the blunted VEGF-A responses of hyperglycaemic ECs were also restored by empagliflozin, which could be attributed to the restoration of the VEGFR-2 receptor levels on the EC surface. The induction of oxidative stress completely recapitulated most of the aberrant phenotypes exhibited by hyperglycaemic monocytes and endothelial cells, and a general antioxidant N-acetyl-L-cysteine (NAC) was able to mimic the effects of empagliflozin. Conclusions: This study provides data indicating the beneficial role of empagliflozin in reversing hyperglycaemia-induced vascular cell dysfunction. Even though both monocytes and endothelial cells express functional SGLT-2, SGLT-2 is not the primary glucose transporter in these cells. Therefore, it seems likely that empagliflozin does not directly prevent hyperglycaemia-mediated enhanced glucotoxicity in these cells by inhibiting glucose uptake. We identified the reduction of oxidative stress by empagliflozin as a primary reason for the improved function of monocytes and endothelial cells in hyperglycaemic conditions. In conclusion, empagliflozin reverses vascular cell dysfunction independent of glucose transport but could partially contribute to its beneficial cardiovascular effects. [ABSTRACT FROM AUTHOR]

One crucial strategy for the treatment of breast cancer involves focusing on the Vascular Endothelial Growth Factor Receptor (VEGFR-2) signaling system. Consequently, the development of new (VEGFR-2) inhibitors is of the utmost importance. In this study, novel 3-thiazolhydrazinylcoumarins were designed and synthesized via the reaction of phenylazoacetylcoumarin with various hydrazonoyl halides and α-bromoketones. By using elemental and spectral analysis data (IR, 1H-NMR, 13C-NMR, and Mass), the ascribed structures for all newly synthesized compounds were clarified, and the mechanisms underlying their formation were delineated. The molecular docking studies of the resulting 6-(phenyldiazenyl)-2H-chromen-2-one (3, 6a–e, 10a–c and 12a–c) derivatives were assessed against VEGFR-2 and demonstrated comparable activities to that of Sorafenib (approved medicine) with compounds 6d and 6b showing the highest binding scores (−9.900 and −9.819 kcal/mol, respectively). The cytotoxicity of the most active thiazole derivatives 6d, 6b, 6c, 10c and 10a were investigated for their human breast cancer (MCF-7) cell line and normal cell line LLC-Mk2 using MTT assay and Sorafenib as the reference drug. The results revealed that compounds 6d and 6b exhibited greater anticancer activities (IC50 = 10.5 ± 0.71 and 11.2 ± 0.80 μM, respectively) than the Sorafenib reference drug (IC50 = 5.10 ± 0.49 μM). Therefore, the present study demonstrated that thiazolyl coumarins are potential (VEGFR-2) inhibitors and pave the way for the synthesis of additional libraries based on the reported scaffold, which could eventually lead to the development of efficient treatment for breast cancer. [ABSTRACT FROM AUTHOR]

Background and objectives: Nuclear factor kappalight-chain-enhancer of activated B cells (NF-κB) inhibition results in an increase in apoptosis. It has been demonstrated that NF-κB subunit p65 phosphorylation at the IκB kinase phosphorylation site serine 536 (Ser536) is essential for the NF-κB nuclear translocation and activation. Therefore, NF-κB can be downregulated by suppressing its phosphorylation. The vascular endothelial growth factor receptor-2 (VEGFR-2) suppression could result in apoptosis induction. Therefore, targeting these pathways via VEGFR-2 inhibitors might have therapeutic potential for cancer treatment. It has been indicated that an antagonist peptide of VEGF, referred to as VGB3, could neutralize and recognize VEGFR2 in the tumoral and endothelial cells. This study aimed to induce apoptosis in human umbilical vein endothelial cells (HUVEC) cells through the inhibition of these signaling pathways. Methods: Effects of different concentrations of VGB3 (1-200 ng/ml) were evaluated on the viability of HUVEC cells using MTT assay. In addition, downstream signaling pathways in HUVE cells were evaluated through quantitative assessment of protein expression via western blotting. Results: The results demonstrated that VGB3 treatment inhibited the growth of HUVEC cells. Moreover, Bcl-2 was decreased in the cells treated with the VGB3 compared to the control. Furthermore, VGB3 significantly enhanced the cleavedcaspase7 levels, which is an indicator of apoptosis progression. Altogether, VGB3 enhanced apoptosis in HUVEC cells. Conclusion: Our results indicate that the peptide might be a potential candidate for antitumor therapy via inhibiting the NF-κB pathway. [ABSTRACT FROM AUTHOR]

Resent study suggests that c-kit+ cells in bone marrow-derived MSCs may differentiate toward cardiamyocytes. However, the properties of c-kit+ MSCs remain unclear. This study isolated c-kit+VEGFR-2+ cells from rat bone marrow-derived MSCs, and assessed potential of c-kit+VEGFR-2+ MSCs to differentiate towards cardiovascular cells and their efficiency of repairing the infarcted myocardium after transplantation. Gene expression profile of the cells was analyzed with RNA-sequencing. Potential of differentiation of the cells was determined after induction. Rat models of myocardial infarction were established by ligation of the left anterior descending coronary artery. The cells were treated with hypoxia and serum deprivation for four hours before transplantation. Improvement of cardiac function and repair of the infarcted myocardium were assessed at four weeks after transplantation. Gene expression profile revealed that c-kit+VEGFR-2+ MSCs expressed most smooth muscle-specific and myocardium-specific genes, while expression of endothelium-specific genes was upregulated significantly. After induction with VEGF or TGF-β for two weeks, the cells expressed CD31 and α-SMA respectively. At three weeks, BMP-2-induced cells expressed cTnT. After transplantation of the cells, cardiac function was improved, scar size of the infarcted myocardium was decreased, and angiogenesis and myocardial regeneration were enhanced significantly. Moreover, paracrine in the myocardium was increased after transplantation. These results suggest that c-kit+VEGFR-2+ MSCs have a potential of differentiation towards cardiovascular cells. Transplantation of c-kit+VEGFR-2+ MSCs is effective for repair of the infarcted myocardium. c-kit+VEGFR-2+ MSCs may be a reliable source for cell therapy of ischaemic diseases. [ABSTRACT FROM AUTHOR]

Background: Inhibition of vascular endothelial growth factor receptor 2 (VEGFR-2) tyrosine kinase by small molecules has become a promising target in the treatment of cancer. Objective: In this study, we approached pharmacophore modeling coupled with a structure-based virtual screening workflow to identify the potent inhibitors. Methods: The top selected hit compounds have been rescored using the MM/GBSA approach. To understand the molecular reactivity, electronic properties, and stability of those inhibitors, we have employed density functional theory and molecular dynamics. Following that, the best 21 hit compounds have been further post-processed with a Quantum ligand partial charge-based rescoring process and further validated by implementing molecular dynamics simulation. Results: The ten hit compounds have been hypothesized and considered as potent inhibitors of VEGFR-2 tyrosine kinase. This study also signifies the contribution of QM-based ligand partial charge, which is more accurate in predicting reliable free binding energy and filtering large ligand libraries to hit optimization, rather than assigning those of the force field-based method. From the binding pattern analysis of all the complexes, amino acids, such as Glu885, Cys919, Cys1045, Thr916, Thr919, and Asp1046, were found to have comprehensive interaction with the hit compounds. Conclusion: Hence, this could prove to be useful as a potential inhibition site of the VEGFR-2 tyrosine kinase domain for future researchers. Moreover, this study also emphasizes the conformational changes upon ATP binding, based on either the receptor's rigidity or flexibility. [ABSTRACT FROM AUTHOR]

The vascular endothelial growth factor (VEGF) and its cell surface receptor, as well as the human VEGFR-2 domain kinase, are some of the signaling pathways that have received the most attention in this field. This study aimed to identify novel molecules as VEGFR-2 inhibitors using 3D-QSAR modeling based on 1,2,3-triazole. Docking studies and dynamic simulations were performed to analyze novel interactions with the inhibitors and validate the molecular docking, dynamic simulations, and ADMET analyses. The optimized CoMSIA/SEH model showed good statistical results, and molecular docking and molecular dynamics simulations demonstrated stability of M3 ligand with the receptor and provided insight into ligand-receptor interactions. The newly developed compounds performed well in ADMET evaluations and showed promising results using Lipinski's rule of five, suggesting that the molecule M3 could be a useful anti-angiogenesis agent. In conclusion, this study provides insights into the structure-activity relationship of VEGFR-2 inhibitors and identifies M3 as a potential new anti-angiogenesis drug. The methodology used in this study can be applied to other similar drug targets to discover new and potent inhibitors.

Herin, new nicotinamide candidates were designed and synthesized as VEGFR-2 inhibitors. In vitro antiproliferative activities were assessed against MCF-7, HepG-2 and HCT-116 cancer cell lines. The top cytotoxic members 15a , 15b , 16, 18a , and 18b were estimated against their selected target (VEGFR-2). Further mechanistic tests were studied for the most potent cytotoxic candidate 18a , these studies revealed the ability of compound 18a to hinder the progression of HCT-116 cells at S and Pre-G1phases besides boosting early and late apoptosis. Also compound 18a was found to significantly decrease the levels immunomodulatory proteins TNF-α and IL-6 while showing a four-fold rise in an apoptotic marker caspase-3 when compared to control cells. The therapeutic index of the designed derivatives was evaluated by computational ADMET and toxicity calculations as well as their potentiality to occupy the VEGFR-2 active site was signposted by molecular docking assessments. Finally, molecular dynamic simulation studies of compound 18a -VEGFR-2 complex indicated the high steadiness of compound 18a in the VEGFR-2 active site. This study presents compound 18a as a lead candidate that can be optimized to get a strong VEGFR-2 inhibitor.Communicated by Ramaswamy H. Sarma.

Aim: New phenyldiazene scaffold-linked heterocyclic pyrazole, pyrimidinone, pyrimidinthione, and/or triazine rings have been developed and synthesized., Methods & Results: Cytotoxicity of our derivatives was estimated on four cancer and VERO normal cell lines targeting EGFR T790M (epidermal growth factor receptor) and VEGFR-2 (vascular endothelial growth factor receptor-2) enzymes. Our new derivatives selectively inhibited both VEGFR-2 and EGFR as they have the essential structural requirements for inhibitors of both receptors. Derivative 14 was the most active on A549, HCT116, HepG2, and MCF-7 cancers with half-maximal inhibitory concentration (IC 50 ) = 5.50, 9.77, 7.12, and 7.85 µM respectively. The assessed derivatives 5 , 7 , 8, 9, 10, 12 and 14 showed IC 50  = 54.40-62.60 μM against normal VERO (normal kidney) cells with low toxicity. In addition, derivatives 14, 8, 10, 7 and 9 were discovered to be very good active inhibitors of VEGFR-2 at IC 50 values of 1.15, 1.35, 140, 1.78 and 1.90 µM, respectively. Furthermore, derivatives 14, 10, 8, and 9 strongly repressed EGFR T790M with IC 50  = 0.28, 0.33, 0.35, and 0.50 µM correspondingly. Additionally, the highly active compounds 8, 10, and 14 showed good ADMET profile., Conclusion: Our derivatives could be considered as anticancer agents with dual VEGFR-2 and EGFR T790M inhibition.

Yu Li,1,&ast; Mei-Ling Wang,1,&ast; Bo Zhang,1 Xiao-Xu Fan,1 Qin Tang,1 Xue Yu,2 Li-Na Li,2 Ang-Ran Fan,2 Hong-Sheng Chang,1 Lan-Zhen Zhang1 1School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 102488, People’s Republic of China; 2School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 102488, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Lan-Zhen Zhang; Hong-Sheng Chang, School of Chinese Materia Medica, Beijing University of Chinese Medicine, Northeast Corner of the Intersection of Sunshine South Street and Baiyang East Road, Fangshan District, Beijing, 102488, People’s Republic of China, Tel +86 10 5391 2122, Email zhanglanzhen01@126.com; chs1971@sina.comBackground: There is growing evidence to suggest that ginsenoside Rd (GRd) has a therapeutic effect on depression, but the specific mechanisms behind its activity require further study.Objective: This study is designed to investigate the antidepressant-like effect and underlying mechanisms of GRd.Methods: In this study, the behavioral despair mouse model of depression and chronic unpredictable mild stress (CUMS) rat model of depression were established to explore the effects of GRd on depression-like behavior and its underlying mechanisms. Behavioral tests were used to evaluate the replication of animal models and depression-like behaviors. The hypoxia-inducible factor-1α (HIF-1α) blocker 2-methoxyestradiol (2-ME) was injected to determine the role of HIF-1α in the antidepressant-like effect of GRd. In addition, molecular biology techniques were used to determine the mRNA and protein expression of HIF-1ɑ signaling pathway and synaptic plasticity-related regulators, that is synapsin 1 (SYN 1) and postsynaptic density protein 95 (PSD 95). In silico binding interaction studies of GRd with focused target proteins were performed using molecular docking to predict the affinity and optimal binding mode between ligands and receptors.Results: Our data show that GRd significantly reversed depression-like behavior and promoted mRNA and protein expression of HIF-1ɑ signaling pathway and synaptic plasticity-related regulators. However, the antidepressant-like effect of GRd disappeared upon inhibition of HIF-1α expression following administration of 2-ME. Furthermore, molecular docking results showed that GRd possessed significant binding affinity for HIF-1α, VEGF, and VEGFR-2.Conclusion: Our results show that GRd exhibits significant antidepressant-like effect and that HIF-1α signaling pathway is a promising target for the treatment of depression.Keywords: ginsenoside Rd, antidepressant effect, HIF-1α-VEGF signaling pathway, VEGFR-2, synaptic plasticity-related regulators, molecular docking

Thiazole and its derivatives have received a lot of attention from researchers due to its wide biological, pharmacological, and anticancer properties. A novel series of 2-[2-[4-Hydroxy-3-substituted benzylidene hydrazinyl]-thiazole-4[5H]-ones (4a–c) and acetoxy derivative (5) were synthesized via using thiosemicarbazones (2a–c). The structure of the thiazole derivatives (4a–c) and 5 in these compounds was confirmed by spectroscopic techniques (IR and NMR), as well as elemental investigations. The synthesized derivatives biological activity was assessed based on their capacity to suppress the growth of the cancer cell lines MCF-7 and HepG2, as well as to halt the cell cycle and trigger apoptosis. Among the synthesized thiazole derivatives, compound 4c was found the most active derivative, with inhibitory concentrations IC50 = 2.57 ± 0.16 and 7.26 ± 0.44 µM in MCF-7 and HepG2, respectively, compared to Staurosporine as the standard drug with IC50 6.77 ± 0.41 and 8.4 ± 0.51 µM, respectively. Additionally, compound 4c blocked vesicular endothelial growth factor receptor-2 (VEGFR-2), according to our results (IC50 = 0.15 µM), compared to Sorafenib (IC50 = 0.059 µM) as the standard drug. Moreover, compound 4c induced cell cycle arrest at the G1/S phase, increasing the percentage and accumulation of cancer cells (DNA content) in the pre-G1 phase by 37.36% in MCF-7 cancer cells compared to untreated MCF-7 cells at 2.02%. Also, compound 4c increased the percentage of early and late apoptosis from 0.51% and 0.29%, respectively, in the case of the MCF-7 untreated control sample to 22.39% and 9.51%, respectively, in the MCF-7 treated sample. Furthermore, molecular docking studies of compounds 4a–c and 5 were conducted with four key proteins (aromatase, epidermal growth factor receptor (EGFR), cyclin-dependent kinase 2 (CDK2), and B-cell lymphoma 2 (Bcl-2)) that stimulate the growth, proliferation, and development of cancer cells. Compound 4c exhibited good docking scores with a promising and potential binding affinity toward the active site of selected docked proteins. According to these results, compound 4c showed efficient cytotoxic activity against the tested cancer cells.

New quinoline and isatin derivatives having the main characteristics of VEGFR-2 inhibitors was synthesised. The antiproliferative effects of these compounds were estimated against A549, Caco-2, HepG2, and MDA-MB-231. Compounds 13 and 14 showed comparable activities with doxorubicin against the Caco-2 cells. These compounds strongly inhibited VEGFR-2 kinase activity. The cytotoxic activities were evaluated against Vero cells. Compound 7 showed the highest value of safety and selectivity. Cell migration assay displayed the ability of compound 7 to prevent healing and migration abilities in the cancer cells. Furthermore, compound 7 induced apoptosis in Caco-2 through the expressive down-regulation of the apoptotic genes, Bcl2, Bcl-xl, and Survivin, and the upregulation of the TGF gene. Molecular docking against VEGFR-2 emerged the interactions of the synthesised compounds in a similar way to sorafenib. Additionally, seven molecular dynamics simulations studies were applied and confirmed the stability of compound 13 in the active pocket of VEGFR-2 over 100 ns. [ABSTRACT FROM AUTHOR]

In this study, a set of novel benzoxazole derivatives were designed, synthesised, and biologically evaluated as potential VEGFR-2 inhibitors. Five compounds (12d, 12f, 12i, 12l, and 13a) displayed high growth inhibitory activities against HepG2 and MCF-7 cell lines and were further investigated for their VEGFR-2 inhibitory activities. The most potent anti-proliferative member 121 (IC50 = 10.50 µM and 15.21 µM against HepG2 and MCF-7, respectively) had the most promising VEGFR-2 inhibitory activity (IC50 = 97.38 nM). A further biological evaluation revealed that compound 12l could arrest the HepG2 cell growth mainly at the Pre-G1 and G1 phases. Furthermore, compound 12l could induce apoptosis in HepG2 cells by 35.13%. likely, compound 12l exhibited a significant elevation in caspase-3 level (2.98-fold) and BAX (3.40-fold), and a significant reduction in Bcl-2 level (2.12-fold). Finally, docking studies indicated that 12l exhibited interactions with the key amino acids in a similar way to sorafenib. [ABSTRACT FROM AUTHOR]

Background and purpose: The objective of this study was to investigate the pharmacokinetics, safety, and antitumor activity of apatinib, a vascular endothelial growth factor receptor 2 inhibitor, in advanced gastric adenocarcinoma or gastroesophageal junction adenocarcinoma and evaluate the effect of dose titration on dosage optimization for individual patients. Methods: Patient with advanced gastric adenocarcinoma progressed after at least one line of chemotherapy were enrolled. Apatinib was given orally once daily starting at 500 mg for 14 days, then up-titrated to 750 mg for 14 days, and then proceeded to a maximum dose of 850 mg. Dose up-titration determination was based on toxicity. The 28-day treatment cycles continued until disease progression, intolerable toxicities, withdrawal of consent, or investigator' decision. Results: A total of 60 patients were enrolled, with 17, 18, and 25 patients receiving a maximum dose of 500 mg, 750 mg, and 850 mg, respectively. The pharmacokinetic parameters varied considerably, with the interpatient coefficient of variation for steady state areas under the plasma concentration time curve (AUCss) and the mean maximum concentration of both > 50%. During 500 mg and 750 mg dosing stage, drug exposures in patients with a maximum dosage of 850 mg were lower than in those not titrated to 850 mg. Patients with total gastrectomy exhibited significantly lower AUCss than patients with partial or no gastrectomy (p = 0.004 and 0.032, respectively). Toxicities were tolerable, and disease control rate was 39.5% (95% CI 25.0%-55.6%). Conclusions: Apatinib dose titration based on toxicity could be used in clinical practice to provide optimal dosage for individual patients. [ABSTRACT FROM AUTHOR]

A series of benzimidazole-tethered pyrrolones and N-benzylpyrrolones were synthesized, charac-terized, and explored for their in vitro anti-proliferative activities. The cytotoxicity of the synthesized com-pounds was evaluated against three cancer cell lines, A549, MCF7, and DU145. (E)-5-(1H-Benzimidazol-2-yl)-3-(3,4,5-trimethoxbenzylidene)-1H-pyrrol-2(3H)-one having three methoxy groups at 3,4,5-positions exhibited excellent activity against A549, MCF7, and DU145 cancer cell lines with IC50 values of 8.3±0.53, 7.2±1.42, and 7.7±0.13 µM, respectively. Another pyrrolone derivative with one hydroxy and one methoxy substituents, (E)-5-(1H-benzimidazol-2-yl)-3-(4-hydroxy-3-methoxybenzylidene)-1H-pyrrol-2(3H)-one, also displayed very good activity against A549, MCF7, and DU145 cell lines with IC50 values of 9.6±0.12, 7.3±0.24, and 8.7± 0.24 µM, respectively. Molecular docking study revealed that all compounds fit into the pocket of VEGFR-2 within the key amino acid residues Glu885, Cys919, and Asp1046. The docking scores and binding energies were very consistent with the experimental anticancer activity. Pharmacokinetic (ADME) parameters of the potent derivatives were also found to be within an acceptable range. It could be concluded that benzimidazole-linked pyrrolones are more potent than their benzylpyrrolone analogs, and therefore this class of compounds could be explored further for the development of potent anticancer agents. [ABSTRACT FROM AUTHOR]

A new series of thiourea or thioacetamide linked quinazoline derivatives has been synthesized and tested for cytotoxicity against the HCT116 and MCF-7 cell lines. Compound 10b, demonstrates strong antiproliferative effect against both colon HCT-116 and MCF-7 cell lines. Compound 10b interrupts the HCT-116 cell cycle at the G2/M phase. According to DNA flow cytometry and annexin test, hybrid 10b is also capable of inducing cell cycle disruption and apoptosis in HCT-116 cells. It causes apoptosis by activating caspases-3, increasing proapoptotic Bax and p53 levels, and decreasing Bcl-2 protein levels. As a result, the novel derivative 10b may be regarded as a promising lead to antitumor agents development. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor receptor (VEGFR) expression in oral squamous cell carcinoma (OSCC) promotes tumor growth through both autocrine and paracrine signaling. VEGF-positive OSCC cases are associated with a high depth of invasion, increased metastasis, and poor prognosis. In this study we established and then molecularly and functionally analyzed an OSCC cell line that co-expresses VEGF-A, VEGFR-1, and VEGFR-2, termed HCM-SqCC010 cells. VEGF-A, VEGFR-1, and VEGFR-2 expression in HCM-SqCC010 cells were examined by immunohistochemistry and immunoblotting. Expression and inhibition of VEGF-A, VEGFR-1, and VEGFR-2 in HCM-SqCC010 cells were verified by quantitative real-time PCR. Our analysis of HCM-SqCC010 cells revealed that their proliferation depended on VEGF-A, and selective inhibition of VEGFR-1 or VEGFR-2 resulted in decreased cell growth. We established an OSCC cell line, HCM-SqCC010, that expresses VEGF-A, VEGFR-1, and VEGFR-2. This triple-positive cell line showed no effect from a molecular targeted drug toward VEGF-A, but it did show strong cell growth inhibition in response to a VEGFR inhibitor. Thus, new therapeutic strategies against OSCC should include a VEGFR inhibitor. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to obtain an insight into the role of the vascular endothelial growth factor (VEGF) in pregnancy-associated mammary epithelial development and angiogenesis. However, we examined the primary VEGF receptor (VEGFR-2) in the mouse mammary cycle. Materials and Methods: The virgin (1012 weeks), days 10 and 18 of pregnancy (P-10 and P-18), days 0, 5, 10, and 20 of lactation (L-0, L-5, L-10, and L-20), and days 5 and 10 of post-weaning (W-5 and W-10) stage were all used in this study. Immunohistochemistry and Western blotting were carried out on mammary tissues taken from three mice at each stage. Results: VEGFR-2 was detected immunohistochemically in the cytoplasm of mammary epithelial and endothelial cells. Immunostaining for VEGFR-2 was consistently positive in mammary endothelial cells across all stages, whereas staining intensity in epithelial cells varied across the mammary cycle. Additionally, immunoblot analysis indicated a 220 kDa unique band of VEGFR-2 protein at all stages of the mammary cycle, with the maximum expression reported toward the end of pregnancy and gradually decreasing toward the end of lactation. Conclusion: In conclusion, the presence of VEGFR-2 in the mammary epithelium in addition to the endothelium suggests that VEGF plays an autocrine and paracrine role in the development, proliferation, and differentiation of the mammary epithelium during pregnancy. [J Adv Vet Anim Res 2021; 8(4.000): 581-588]

There are no effective therapeutic options for locally advanced head and neck squamous cell carcinoma (HNSCC). Additionally, there is no standard therapy for patients subjected to multiple lines of treatment. Angiogenesis plays a key role in tumor growth and metastasis. Therefore, inhibition of tumor angiogenesis is an important strategy for tumor therapy. Apatinib is a novel tyrosine kinase inhibitor that inhibits angiogenesis by targeting vascular endothelial growth factor receptor-2 (VEGFR-2). The effect of apatinib on HNSCC has not been clearly established. In this study, we administered apatinib in combination with anti-epidermal growth factor receptor (EGFR) targeted and systemic chemotherapy for the treatment of oral cancer and to achieve better disease outcomes. To avoid fatal bleeding, after achieving good clinical outcomes, the follow-up treatment plan was adjusted. The efficacy of apatinib combined with anti-EGFR targeted and systemic chemotherapy for the treatment of oral cancer has not been previously reported. Our findings show the therapeutic potential of apatinib for advanced HNSCC patients with multiple lines of chemotherapy, especially for patients with large neck masses.