Vascular Endothelial Growth Factor Receptor 2 Active Site Research Articles

Coumarin derivatives with potential anticancer and antibacterial activity: Design, synthesis, VEGFR-2 and DNA gyrase inhibition, and in silico studies.

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.

New Oxazolo[5,4-d]pyrimidines as Potential Anticancer Agents: Their Design, Synthesis, and In Vitro Biological Activity Research.

Cancer is a large group of diseases in which the rapid proliferation of abnormal cells generally leads to metastasis to surrounding tissues or more distant ones through the lymphatic and blood vessels, making it the second leading cause of death worldwide. The main challenge in designing a modern anticancer therapy is to develop selective compounds that exploit specific molecular targets. In this work, novel oxazolo[5,4-d]pyrimidine derivatives were designed, synthesized, and evaluated in vitro for their cytotoxic activity against a panel of four human cancer cell lines (lung carcinoma: A549, breast adenocarcinoma: MCF7, metastatic colon adenocarcinoma: LoVo, primary colon adenocarcinoma: HT29), along with their P-glycoprotein-inhibitory ability and pro-apoptotic activity. These oxazolo[5,4-d]pyrimidine derivatives, which are structurally similar to nucleic purine bases in general, are characterized by the presence of a pharmacologically favorable isoxazole substituent at position 2 and aliphatic amino chains at position 7 of the condensed heterocyclic system. In silico analysis of the obtained compounds identified their potent inhibitory activity towards human vascular endothelial growth factor receptor-2 (VEGFR-2). Molecular docking was performed to assess the binding mode of new derivatives to the VEGFR-2 active site. Then, their physicochemical, pharmacokinetic, and pharmacological properties (i.e., ADME—administration, distribution, metabolism, and excretion) were also predicted to assess their druglikeness. In particular, compound 3g (with a 3-(N,N-dimethylamino)propyl substituent) was found to be the most potent against the HT29 cell line, with a 50% cytotoxic concentration (CC50) of 58.4 µM, exceeding the activity of fluorouracil (CC50 = 381.2 μM) and equaling the activity of cisplatin (CC50 = 47.2 µM), while being less toxic to healthy human cells (such as normal human dermal fibroblasts (NHDFs)) than these reference drugs. The results suggest that compound 3g is a potentially promising candidate for the treatment of primary colorectal cancer.

N-Substituted-4-phenylphthalazin-1-amine-derived VEGFR-2 inhibitors: Design, synthesis, molecular docking, and anticancer evaluation studies.

In accordance with the significant impetus of the discovery of potent vascular endothelial growth factor receptor 2 (VEGFR-2) inhibitors, herein, we report the design, synthesis, and anticancer evaluation of 12 new N-substituted-4-phenylphthalazin-1-amine derivatives against HepG2, HCT-116, and MCF-7 cells as VEGFR-2 inhibitors. The results of the cytotoxicity investigation indicated that HCT-116 and MCF-7 were the most sensitive cell lines to the influence of the newly synthesized derivatives. In particular, compound 7awas found to be the most potent derivative among all the tested compounds against the three cancer cell lines, HepG2, HCT116, and MCF-7, with IC50 = 13.67 ± 1.2, 5.48 ± 0.4, and 7.34 ± 0.6 µM, respectively, which is nearly equipotent to that of sorafenib (IC50 = 9.18 ± 0.6, 5.47 ± 0.3, and 7.26 ± 0.3 µM, respectively). All synthesized derivatives,4a,b-8a-c, were evaluated for their inhibitory activities against VEGFR-2. The tested compounds displayed high to low inhibitory activity, with IC50 values ranging from 0.14 ± 0.02 to 9.54 ± 0.85 µM. Among them, compound 7a was found to be the most potent derivative that inhibited VEGFR-2 at an IC50 value of 0.14 ± 0.02 µM, which is nearly 72% of that of the sorafenib IC50 value (0.10 ± 0.02 µM). Compounds 7b, 8c, 8b, and 8a exhibited very good activity with IC50 values of 0.18 ± 0.02, 0.21 ± 0.03, 0.24 ± 0.02, and 0.35 ± 0.04 µM, respectively. Molecular modeling studies were carried out for all compounds against the VEGFR-2 active site. The data obtained from biological testing highly correlated with that obtained from molecular modeling studies. However, these modifications led to new phthalazine derivatives with higher VEGFR-2 inhibitory activities than vatalanib and which are nearly equipotent to sorafenib.

Novel pyrazolopyrimidine urea derivatives: Synthesis, antiproliferative activity, VEGFR-2 inhibition, and effects on the cell cycle profile.

A series of novel diaryl urea pyrazolopyrimidine derivatives was designed and synthesized. All the synthesized compounds were evaluated for cytotoxic activity by the National Cancer Institute. A significant antiproliferative activity at a 10-µM dose was shown by four compounds (5c, 5e, 5g, and 5h), and they were accordingly evaluated at five concentrations. They showed a potent and broad-spectrum antiproliferative activity, with GI50 values between 0.553 and 3.80 µM and TGI values in the range of 2.17-100 µM. These four compounds potently inhibited the vascular endothelial growth factor receptor-2 (VEGFR-2) with IC50 values in the nanomolar range. Molecular docking attributed their potent VEGFR-2 inhibitory activity to their interactions with key amino acids in the VEGFR-2 active site. Their flow cytometric analysis showed that they exerted their cytotoxic activity by reduction of the cellular proliferation and by induction of cell cycle arrest at the G2/M phase. Additionally, they induced DNA degradation or fragmentation, confirming the role of apoptosis in the cancer cell death and cytotoxicity induced by these compounds.

Design, synthesis, molecular docking, and anticancer activity of benzoxazole derivatives as VEGFR-2 inhibitors.

Novel series of benzoxazoles 4a-f -16 were designed, synthesized, and evaluated for anticancer activity against HepG2, HCT-116, and MCF-7 cells. HCT-116 was the most sensitive cell line to the influence of the new derivatives. In particular, compound 5e was found to be the most potent against HepG2, HCT-116, and MCF-7 with IC50 = 4.13 ± 0.2, 6.93 ± 0.3, and 8.67 ± 0.5 µM, respectively. Compounds 5c , 5f , 6b , 5d , and 6c showed the highest anticancer activities against HepG2 cells with IC50 of 5.93 ± 0.2, 6.58 ± 0.4, 8.10 ± 0.7, 8.75 ± 0.7, and 9.95 ± 0.9 µM, respectively; HCT-116 cells with IC50 of 7.14 ± 0.4, 9.10 ± 0.8, 7.91 ± 0.6, 9.52 ± 0.5, and 12.48 ± 1.1 µM, respectively; and MCF-7 cells with IC50 of 8.93 ± 0.6, 10.11 ± 0.9, 12.31 ± 1.0, 9.95 ± 0.8, and 15.70 ± 1.4 µM, respectively, compared with sorafenib as a reference drug with IC50 of 9.18 ± 0.6, 5.47 ± 0.3, and 7.26 ± 0.3 µM, respectively. The most active compounds 5c-f and 6b,c were further evaluated for their vascular endothelial growth factor receptor-2 (VEGFR-2) inhibition. Compounds 5e and 5c potently inhibited VEGFR-2 at lower IC50 values of 0.07 ± 0.01 and 0.08 ± 0.01 µM, respectively, compared with sorafenib (IC50 = 0.1 ± 0.02 µM). Compound 5f potently inhibited VEGFR-2 at low IC50 value (0.10 ± 0.02 µM) equipotent to sorafenib. Our design was based on the essential pharmacophoric features of the VEGFR-2 inhibitor sorafenib. Molecular docking was performed for all compounds to assess their binding pattern and affinity toward the VEGFR-2 active site.

Design and synthesis of 2-phenyl benzimidazole derivatives as VEGFR-2 inhibitors with anti-breast cancer activity.

Three new series of 2-phenyl benzimidazole-based derivatives were designed, synthesized, and evaluated for their in vitro cytotoxic activity against breast cancer (MCF-7) cell lines. Three compounds 8, 9, and 15 showed high cytotoxic activities, with IC50 values of 3.37, 6.30, and 5.84μM, respectively, while they showed comparable cytotoxicity to the standard drug doxorubicin against human normal cells, including nontumorigenic breast epithelial cell line (MCF-10F), skin fibroblast cell line (BJ), and lung fibroblast cell line (MRC-5). Six of the synthesized compounds were screened against vascular endothelial growth factor receptor 2 (VEGFR-2) where compounds 8, 9, 12, and 15 exhibited an outstanding potency in comparison with sorafenib, with IC50 values of 6.7-8.9nM. Molecular docking study assessed the good binding patterns of the most potent compounds with the reported conserved amino acids of VEGFR-2 active site.

Anticancer Evaluation and Docking Study of New Bifunctional Phthalazine Derivatives

Aims and Objective: A series of novel phthalazine derivatives was synthesized with versatile, readily accessible electrophilic and nucleophilic reagents. The newly synthesized compounds were confirmed by the results of spectroscopic measurements. Hence, their potential clinical application investigated in particular for cancer treatment. Materials and Methods: The newly synthesized compounds were characterized by spectroscopic measurements and were tested for their in vitro anticancer activity by MTT assay against human liver cancer cell line. Docking study of all the synthesized compounds was performed within the active site of the enzyme VEGFR-2 (Vascular Endothelial Growth Factor Receptor-2). Results: The quinazoline derivative 12 emerged as the most potent compound in this study with an IC50 value of 5.4 µM. Docking study showed that the synthesized compounds were fit in the VEGFR-2 active site almost at the same position of sorafenib and vatalanib with comparable docking scores (-15.20 to -8.92 was kcal/mol). Conclusion: we have synthesized a novel series of phthalazine derivatives and evaluated their potential anticancer activity against HEPG2 cell line. The quinazoline derivative 12 emerged as the most potent compound in this study with an IC50 value of 5.4 µM. The SAR and docking studies pointed out that rigidification of the structure resulted in better activity and better binding within the active site of VEGFR-2 as in compounds 3, 5, 6 and 12. These results introduced new phthalazine derivatives having promising activity which could lead to the development of more potent anticancer agents.

Synthesis and Biological Evaluation of Glycyrrhetic Acid Derivatives as Potential VEGFR2 Inhibitors.

Vascular endothelial growth factor receptor 2 (VEGFR2) has been proven to play a major role in the regulation of tumor angiogenesis. A series of novel glycyrrhetic acid derivatives were synthesized and evaluated for their VEGFR2 inhibitory activity as well as their antiproliferative properties against four cancer cell lines (MCF-7, HeLa, HepG2, and A549). In vitro biological evaluations against these human tumor cell lines indicate that most of the prepared compounds have antiproliferative activities; compound 3 a (3β-hydroxy-30-(4-phenyl-1-piperazinyl)olean-12-ene-11,30-dione) exhibited the best inhibitory activity against MCF-7 cells, with an IC50 value of 1.08 μm. Compound 3 a also showed the most potent inhibitory activity against VEGFR2 tyrosine kinase, with an IC50 value of 0.35 μm. Docking simulations were performed with the aim of discovering the binding mode of compound 3 a, and the results indicate that 3 a could bind at the VEGFR2 active site.

Design, synthesis, molecular docking and cytotoxic evaluation of novel 2-furybenzimidazoles as VEGFR-2 inhibitors

Inhibition of angiogenesis through inhibition of vascular endothelial growth factor receptor 2 (VEGFR-2) has been applied in cancer therapy because of its important role in promoting cancer growth and metastasis. In the presented study, a series of benzimidazol-furan hybrids was designed and synthesized through facile synthetic pathways. Evaluation of the synthesized compounds for their in vitro cytotoxic activity against breast (MCF-7) and hepatocellular (HepG2) carcinoma cell lines was performed. Two of the synthesized conjugates, 10b and 15, showed potent antiproliferative properties against MCF-7 cell line (IC50 = 21.25, 21.35 μM, respectively) in comparison to tamoxifen (IC50 = 21.57 μM). Additionally, compounds 10a, 10b, 15 and 17 showed promising potency (IC50 = 25.95, 22.58, 26.94 and 31.06 μM, respectively) against liver carcinoma cell line HepG2 in contrast to cisplatin (IC50 = 31.16 μM). Moreover, in vitro evaluation of the synthesized compounds for their effect on the level of VEGFR-2 in MCF-7 cell line showed their potent inhibitory activity relative to control untreated cells. Four compounds 10a, 10b, 14 and 15 showed 92–96% reduction in VEGFR-2 level, compared with tamoxifen and sorafenib which showed inhibition percentage of 98% and 95.75%, respectively. Compound 10a was found to have promising VEGFR-2 inhibitory activity (IC50 = 0.64 μM) in comparison to sorafenib (IC50 = 0.1 μM). Molecular docking was performed to study the binding pattern of the newly synthesized compounds with VEGFR-2 active site. Molecular docking attributed their good VEGFR-2 inhibitory activity to their hydrogen bonding interaction with the key amino acids in VEGFR-2 active site, Glu885 and Asp1046, and their hydrophobic interaction by their 2-furylbenzimidazole moiety with the allosteric hydrophobic back pocket in a type III inhibitors-like binding mode. The binding interaction is augmented by a ring substituent with long chain extension at position 1 of the benzimidazole due to its hydrophobic interaction with the hydrophobic side chains of the amino acids at the interface between the ATP binding site and the allosteric back pocket. Structure-activity relationship (SAR) was inferred for future optimization based on the performed biological and docking studies.

Ab-initio and Conformational Analysis of a Potent VEGFR-2 Inhibitor: A Case Study on Motesanib.

Vascular endothelial growth factor receptor-2 (VEGFR-2); a cell surface receptor for vascular endothelial growth factors, is a key pharmacological target involved in the cell proliferation/angiogenesis. It has been revealed that VEGFR-2 induces proliferation through activation of the extracellular signal-regulated kinases pathway. In this regard, targeting the VEGFR-2 has been considered as an efficient route to develop anti-tumor agents. Motesanib is a small-molecule antagonist of VEGFR-1, 2, and 3 (IC50s; 2 nM, 3 nM, 6 nM, respectively). It is an experimental drug candidate undergoing clinical trials against some types of cancer. In the present study, Motesanib (AMG 706) was evaluated in terms of its binding energies with individual amino acids of VEGFR-2 active site (amino acid decomposition analysis). For this purpose, functional B3LYP associated with split valence basis set using polarization functions (Def2-SVP) was used. Comparative conformational analysis of the ligand in optimized and crystallographic states revealed that Motesanib does not necessarily bind to the VEGFR-2 active site in its minimum energy conformer.

Synthesis, biological activity and docking study of some new isatin Schiff base derivatives

A set of novel Schiff bases of isatin were synthesized and characterized by reaction of isatin with various aromatic or heterocyclic primary amines. Cytotoxic activities for some of the synthesized compounds were evaluated by MTT assay in three human cancer cell lines (HeLa, LS180 and Raji). Half of the tested compounds showed good cytotoxicity in HeLa cells. 3-(2-(4-nitrophenyl) hydrazono) indolin-2-one was found to be the most potent molecule among the studied isatin derivatives. Docking studies of 3-substituted indolin-2-one scaffolds on vascular endothelial growth factor receptor 2 (VEGFR-2) involved in cell proliferation and angiogenesis was performed. 3-(naphthalen-1-ylimino) indolin-2-one and 3-(2-(4-nitrophenyl) hydrazono) indolin-2-one exhibited higher docking binding energies with receptor. For 3-(2-(4-nitrophenyl) hydrazono) indolin-2-one, H-bond interaction with Cys917 residue of target active site was in common with reported crystallographic benzoimidazole derivative (PDB code: 2OH4). New key H-bonds involving Glu915, Asn921, and Arg1049 residues in VEGFR-2 active site could be detected for 3-(2-(4-nitrophenyl) hydrazono) indolin-2-one. Extended lipophilic rings containing H-bond acceptors on the 3 position of indoline scaffold seemed to be important factors in developing potent VEGFR-2 inhibitors virtually. Based on the ligand efficiency indices, some isoxazole or thiazole substituted isatin derivatives may be regarded as efficient candidates for further molecular developments of anticancer agents.

Study of differences in the VEGFR2 inhibitory activities between semaxanib and SU5205 using 3D-QSAR, docking, and molecular dynamics simulations

Semaxanib (SU5416) and 3-[4′-fluorobenzylidene]indolin-2-one (SU5205) are structurally similar drugs that are able to inhibit vascular endothelial growth factor receptor-2 (VEGFR2), but the former is 87 times more effective than the latter. Previously, SU5205 was used as a radiolabelled inhibitor (as surrogate for SU5416) and a radiotracer for positron emission tomography (PET) imaging, but the compound exhibited poor stability and only a moderate IC 50 toward VEGFR2. In the current work, the relationship between the structure and activity of these drugs as VEGFR2 inhibitors was studied using 3D-QSAR, docking and molecular dynamics (MD) simulations. First, comparative molecular field analysis (CoMFA) was performed using 48 2-indolinone derivatives and their VEGFR2 inhibitory activities. The best CoMFA model was carried out over a training set including 40 compounds, and it included steric and electrostatic fields. In addition, this model gave satisfactory cross-validation results and adequately predicted 8 compounds contained in the test set. The plots of the CoMFA fields could explain the structural differences between semaxanib and SU5205. Docking and molecular dynamics simulations showed that both molecules have the same orientation and dynamics inside the VEGFR2 active site. However, the hydrophobic pocket of VEGFR2 was more exposed to the solvent media when it was complexed with SU5205. An energetic analysis, including Embrace and MM-GBSA calculations, revealed that the potency of ligand binding is governed by van der Waals contacts.