Potent VEGFR-2 Research Articles

Synthesis, Characterization, Pharmacogenomics, and Molecular Simulation of Pyridinium Type of Ionic Liquids and Their Applications.

Substituted pyridinium bromides are prepared by conventional and solvent-free greener methods. The solvent-free solid-phase (greener) method is superior to the conventional method because of its nontoxic nature, simple reaction setup procedure, and twenty times less time consumption. Column chromatography and toxic organic solvents are avoided. Substituted pyridinium salts 1-2(a-c) show excellent catalytic response in the preparation of β-amino carbonyl derivatives using the conventional approach. Pharmacokinetics is very important in target validation and in shifting a lead compound into a drug. The physicochemical properties discussed here can be used effectively in the drug designing candidate, which is a cumbersome process in clinical research. In addition, molecular simulations are demonstrated, and compounds 1-2(a-c) possess the most potent VEGFR-2 kinase protein inhibitory activities, and most interestingly, compound 2a strongly binds and regulates the VEGFR-2 kinase activity in therapeutic approaches and cancer prevention.

Identification of new theobromine-based derivatives as potent VEGFR-2 inhibitors: design, semi-synthesis, biological evaluation, and in silico studies.

This study aimed to design anticancer theobromine derivatives inhibiting VEGFR-2. The new compounds were tested in vitro to evaluate their effectiveness against MCF-7 and HepG2 cancer cell lines. Among these compounds, 15a showed the highest cytotoxicity against HepG2, with an IC50 value of 0.76 μM, and significant anti-proliferative effects on MCF-7, with an IC50 value of 1.08 μM. Notably, the selectivity index of 15a against the two cancer cells was 98.97 and 69.64, respectively. Moreover, 15a demonstrated potent VEGFR-2 inhibitory activity (IC50 = 0.239 μM). Further investigations revealed that 15a induced apoptosis in HepG2 cells, significantly increasing early-stage and late-stage apoptosis percentages from 3.06% and 0.71% to 29.49% and 9.63%, respectively. It also upregulated caspase-3 and caspase-9 levels by 3.45-fold and 2.37-fold, respectively compared to control HepG2 cells. Additionally, 15a inhibited the migration and wound healing ability of HepG2 cells. Molecular docking confirmed the binding affinities of the semi-synthesized compounds to VEGFR-2, consistent with in vitro results. Several computational analyses (DFT, MD simulations, MM-GBSA, PLIP, and essential dynamics) supported the stability of the 15a-VEGFR-2 complex. Overall, the biological and computational findings suggest that compound 15a could be a promising lead compound for the development of a novel apoptotic anticancer agent.

Discovery of new quinoline and isatine derivatives as potential VEGFR-2 inhibitors: design, synthesis, antiproliferative, docking and MD simulation studies

A new set of quinoline and isatine derivatives were synthesized as antiangiogenic VEGFR-2 inhibitors. On a biological level, the in vitro ability of the obtained candidates to inhibit VEGFR-2 was found to be strong with IC50 values in the range of 76.64–175.50 nM. To investigate the cytotoxicity and safety, all compounds were tested against a panel of four cancer cell lines (A549, Caco2, HepG2 and MDA) as well as two normal cell lines (Vero and WI-38). Interestingly, compound 12 exhibited noticeable cytotoxicity against A549, Caco2 and MDA with IC50 values of 5.40, 0.58 and 0.94 µM, respectively. These results were better and comparable to that of doxorubicin (0.70, 0.82 and 0.90 µM, respectively) with more than three folds higher selectivity index against the Caco2 cell lines. Compound 9 prevented the healing of the cancer cells at a low concentration. Also, the compound’s potential to induce programmed cell death in Caco-2 was proved through the significant down regulating of the expression of Bcl2, Bcl-xl and Survivin in addition to the slight upregulation of the TGF-β gene. The cell cycle analysis indicated that compound 9 arrested the Caco-2 cells in the G2/M phase. Interestingly, the molecular docking studies against VEGFR-2 revealed the correct binding of the targeted compounds similar to sorafenib. Furthermore, MD experiments validated the binding of compound 12 with VEGFR-2 over 100 ns, as well as MM-PBSA analysis that confirmed the precise binding with optimum energy. Finally, ADMET analysis showed the general drug-likeness and confirmed the safety of the tested compounds. Communicated by Ramaswamy H. Sarma

Design, Synthesis, Molecular Modeling, and Anticancer Evaluation of New VEGFR-2 Inhibitors Based on the Indolin-2-One Scaffold.

A new series of indoline-2-one derivatives was designed and synthesized based on the essential pharmacophoric features of VEGFR-2 inhibitors. Anti-proliferative activities were assessed for all derivatives against breast (MCF-7) and liver (HepG2) cancer cell lines, using sunitinib as a reference agent. The most potent anti-proliferative derivatives were evaluated for their VEGFR-2 inhibition activity. The effects of the most potent inhibitor, 17a, on cell cycle, apoptosis, and expression of apoptotic markers (caspase-3&-9, BAX, and Bcl-2) were studied. Molecular modeling studies, such as docking simulations, physicochemical properties prediction, and pharmacokinetic profiling were performed. The results revealed that derivatives 5b, 10e, 10g, 15a, and 17a exhibited potent anticancer activities with IC50 values from 0.74-4.62 µM against MCF-7 cell line (sunitinib IC50 = 4.77 µM) and from 1.13-8.81 µM against HepG2 cell line (sunitinib IC50 = 2.23 µM). Furthermore, these compounds displayed potent VEGFR-2 inhibitory activities with IC50 values of 0.160, 0.358, 0.087, 0.180, and 0.078 µM, respectively (sunitinib IC50 = 0.139 µM). Cell cycle analysis demonstrated the ability of 17a to induce a cell cycle arrest of the HepG2 cells at the S phase and increase the total apoptosis by 3.5-fold. Moreover, 17a upregulated the expression levels of apoptotic markers caspase-3 and -9 by 6.9-fold and 3.7-fold, respectively. In addition, 17a increased the expression level of BAX by 2.7-fold while decreasing the expression level of Bcl-2 by 1.9-fold. The molecular docking simulations displayed enhanced binding interactions and similar placement as sunitinib inside the active pocket of VEGFR-2. The molecular modeling calculations showed that all the test compounds were in accordance with Lipinski and Veber rules for oral bioavailability and had promising drug-likeness behavior.

The use of machine learning modeling, virtual screening, molecular docking, and molecular dynamics simulations to identify potential VEGFR2 kinase inhibitors

Targeting the signaling pathway of the Vascular endothelial growth factor receptor-2 is a promising approach that has drawn attention in the quest to develop novel anti-cancer drugs and cardiovascular disease treatments. We construct a screening pipeline using machine learning classification integrated with similarity checks of approved drugs to find new inhibitors. The statistical metrics reveal that the random forest approach has slightly better performance. By further similarity screening against several approved drugs, two candidates are selected. Analysis of absorption, distribution, metabolism, excretion, and toxicity, along with molecular docking and dynamics are performed for the two candidates with regorafenib as a reference. The binding energies of molecule1, molecule2, and regorafenib are − 89.1, − 95.3, and − 87.4 (kJ/mol), respectively which suggest candidate compounds have strong binding to the target. Meanwhile, the median lethal dose and maximum tolerated dose for regorafenib, molecule1, and molecule2 are predicted to be 800, 1600, and 393 mg/kg, and 0.257, 0.527, and 0.428 log mg/kg/day, respectively. Also, the inhibitory activity of these compounds is predicted to be 7.23 and 7.31, which is comparable with the activity of pazopanib and sorafenib drugs. In light of these findings, the two compounds could be further investigated as potential candidates for anti-angiogenesis therapy.

Design, synthesis and biological characteristicsof pyrazolo[3,4-d]pyrimidine derivatives as potential VEGFR-2 inhibitors.

Aim: Several VEGFR-2 inhibitors with the structure of [3,4-d]pyrimidine andbased on sorafenibwere designed and synthesized. Materials & methods: Cytotoxic activity was evaluated by MTT, wound healingand clone formation assays. Cell cycle and apoptosis were analyzed by flow cytometry. Molecular simulation and western blot were alsoapplied. Results: Among them, II-1 significantly inhibited tumor cellular activity (IC50=5.90±0.05μM on HepG2 cells)compared with sorafenib (IC50=9.05±0.54μM on HepG2 cells). Molecular docking demonstrated that II-1 and sorafenib have the same hydrogen binding. Finally, the protein expression of phosphorylated VEGFR-2 was substantially reduced after II-1 treatment. Conclusion: Compound II-1 can inhibit VEFGR-2 activation and is an effective antitumor agent in livercancer cells.

Response to BRAF-targeted Therapy Is Enhanced by Cotargeting VEGFRs or WNT/β-Catenin Signaling in BRAF-mutant Colorectal Cancer Models.

The fact that 10% of colorectal cancer tumors harbor BRAF V600E mutations suggested targeting BRAF as a potential therapy. However, BRAF inhibitors have only limited single-agent efficacy in this context. The potential for combination therapy has been shown by the BEACON trial where targeting the EGF receptor with cetuximab greatly increased efficacy of BRAF inhibitors in BRAF-mutant colorectal cancer. Therefore, we explored whether efficacy of the mutant BRAF inhibitor vemurafenib could be enhanced by cotargeting of either oncogenic WNT/β-catenin signaling or VEGFR signaling. We find the WNT/β-catenin inhibitors pyrvinium, ICG-001 and PKF118-310 attenuate growth of colorectal cancer cell lines in vitro with BRAF-mutant lines being relatively more sensitive. Pyrvinium combined with vemurafenib additively or synergistically attenuated growth of colorectal cancer cell lines in vitro. The selective and potent VEGFR inhibitor axitinib was most effective against BRAF-mutant colorectal cancer cell lines in vitro, but the addition of vemurafenib did not significantly increase these effects. When tested in vivo in animal tumor models, both pyrvinium and axitinib were able to significantly increase the ability of vemurafenib to attenuate tumor growth in xenografts of BRAF-mutant colorectal cancer cells. The magnitude of these effects was comparable with that induced by a combination of vemurafenib and cetuximab. This was associated with additive effects on release from tumor cells and tumor microenvironment cell types of substances that would normally aid tumor progression. Taken together, these preclinical data indicate that the efficacy of BRAF inhibitor therapy in colorectal cancer could be increased by cotargeting either WNT/β-catenin or VEGFRs with small-molecule inhibitors.

Discovery of new fenamate-based derivatives as anticancer agents and potent VEGFR-2 inhibitors

VEGFR-2 is a critical target for the treatment of solid tumors. This work represents synthetic approaches to a new class of fenamate-based derivatives with essential pharmacophoric properties comparable to VEGFR-2 inhibitors. The reaction of tolfenamic acid hydrazide with substituted phenacyl bromide, and phenylisothiocynate derivatives produced novel tolfenamic acid (TA) derivatives (compounds 4 and 5). The target molecules were validated using spectroscopic techniques such as FT-IR and 1HNMR. Docking tests were performed to determine how the synthesized chemicals bind to the putative molecular target, VEGFR-2. The docking results demonstrated that the synthesized compounds could bind VEGFR-2 correctly. Finally, computational physicochemical analysis of the most active candidates revealed that they have favorable assets and reasonable drug-likeness reports.

247P Apatinib combined with chemotherapy versus single chemotherapy in advanced HER-2-negative breast cancer: A randomized, controlled, open-label phase II study

Apatinib is an oral, highly potent tyrosine-kinase inhibitor targeting VEGFR2. Phase II trial of apatinib in triple-negative breast cancer that have failed at least three chemotherapy regimens have demonstrated apatinib dose of 500 mg rather than 750 mg is the recommended starting dose for the heavily pretreated metastatic triple-negative breast cancer (mTNBC) patients with measurable rate of partial response and PFS. This phase II trial aimed to investigate the efficacy and safety of apatinib combined with chemotherapy in patients with HER2-negative advanced breast cancer.

Anti-cancer and immunomodulatory evaluation of new nicotinamide derivatives as potential VEGFR-2 inhibitors and apoptosis inducers: in vitro and in silico studies

New nicotinamide derivatives 6, 7, 10, and 11 were designed and synthesised based on the essential features of the VEGFR-2 inhibitors. Compound 10 revealed the highest anti-proliferative activities with IC50 values of 15.4 and 9.8 µM against HCT-116 and HepG2, respectively compared to sorafenib (IC50 = 9.30 and 7.40 µM). Compound 7 owned promising cytotoxic activities with IC50 values of 15.7 and 15.5 µM against the same cell lines, respectively. Subsequently, the VEGFR-2 inhibitory activities were assessed for the titled compounds to exhibit VEGFR-2 inhibition with sub-micromolar IC50 values. Moreover, compound 7 induced the cell cycle cessation at the cycle at %G2-M and G0-G1phases, and induced apoptosis in the HCT-116. Compounds 7 and 10 reduced the levels of TNF-α by 81.6 and 84.5% as well as IL-6 by 88.4 and 60.9%, respectively, compared to dexamethasone (82.4 and 93.1%). In silico docking, molecular dynamics simulations, ADMET, and toxicity studies were carried out.

New application of novel tetrazine derivatives as potent VEGFR-2 kinase inhibitors and anti-cancer agents.

Background: A novel series of s-tetrazine derivatives was designed as a new scaffold and synthesized efficiently as VEGFR-2 inhibitors for the first time. Methodology & results: The inhibitory activities of the new compounds were tested by MTT assay and enzyme assay, respectively. Western blot assay, cell apoptosis assay and cell migration assay were carried out to study the action mechanism of them. All the synthesized compounds showed evident VEGFR-2 inhibitory activities (IC50 in the range of 88.53-257.55nM). Compounds 23h, 25d, 26e and 27c showed excellent anti-proliferative activities against the four tested cell lines and were better than sorafenib basically. Conclusion: Compounds with good activities based on this novel scaffold can be screened successfully.

Benzoxazole derivatives as new VEGFR-2 inhibitors and apoptosis inducers: design, synthesis, in silico studies, and antiproliferative evaluation

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.

Design and synthesis of thiazolidine-2,4-diones hybrids with 1,2-dihydroquinolones and 2-oxindoles as potential VEGFR-2 inhibitors: in-vitro anticancer evaluation and in-silico studies

A thiazolidine-2,4-dione nucleus was molecularly hybridised with the effective antitumor moieties; 2-oxo-1,2-dihydroquinoline and 2-oxoindoline to obtain new hybrids with potential activity against VEGFR-2. The cytotoxic effects of the synthesised derivatives against Caco-2, HepG-2, and MDA-MB-231 cell lines were investigated. Compound 12a was found to be the most potent candidate against the investigated cell lines with IC50 values of 2, 10, and 40 µM, respectively. Furthermore, the synthesised derivatives were tested in vitro for their VEGFR-2 inhibitory activity showing strong inhibition. Moreover, an in vitro viability study against Vero non-cancerous cell line was investigated and the results reflected a high safety profile of all tested compounds. Compound 12a was further investigated for its apoptotic behaviour by assessing the gene expression of four genes (Bcl2, Bcl-xl, TGF, and Survivin). Molecular dynamic simulations authenticated the high affinity, accurate binding, and perfect dynamics of compound 12a against VEGFR-2.

Molecular Docking and In Vitro Anticancer Screening of Synthesized Arylthiazole linked 2H-indol-2-one Derivatives as VEGFR-2 Kinase Inhibitors.

Indoline-2,3-dione comprises a leading course group of heterocycles endowed with appealing biological actions, including anticancer activity. There are significant justifications for exploring the anticancer activity of Schiff base derivatives of isatin as a vast number of reports have documented remarkable antiproliferative action of isatin nucleus against various cancer cell lines. A series of arylthiazole linked 2H-indol-2-one derivatives (5a-t) was designed and synthesized as potential VEGFR-2 kinase inhibitors keeping the essential pharmacophoric features of standard drugs, like sunitinib, sorafenib, nintedanib, etc. They were evaluated for their in vitro anticancer activity. The aim of this study was to investigate and assess the anticancer potential of isatin-containing compounds along with their kinase inhibition activity. The title compounds were synthesized by reacting substituted isatins with para-substituted arylthiazoles using appropriate reaction conditions. Selected synthesized derivatives went under preliminary screening against a panel of 60 cancer cell lines at NCI, the USA, for single-dose and five dose assays. Molecular docking was performed to explore the binding and interactions with the active sites of the VEGFR-2 receptor (PDB Id: 3VHE). Derivatives 5a, 5b, 5c, 5d, 5g, 5h, and 5m were assessed for in vitro inhibition potency against Human VEGFR-2 using ELISA (Enzyme- Linked Immunosorbent Assay) kit. All the target compounds were determined against human colon cancer cell line SW480 (colorectal adenocarcinoma cells). Cellular apoptosis/necrosis was determined by flow cytometry using annexin V-FITC. DNA content of the cells was analyzed by flow cytometry and the cycle distribution was quantified. Compounds 5a and 5g exhibited noteworthy inhibition during a five-dose assay against a panel of 60 cell lines with MID GI50 values of 1.69 and 1.54 μM, respectively. Also, both the lead compounds 5a and 5g demonstrated promising VEGFR-2 inhibitory activity with IC50 values of 5.43±0.95 and 9.63±1.32 μM, respectively. The aforesaid potent compounds were found effective against SW480 (colorectal adenocarcinoma cells) with IC50 values of 31.44 μM and 106.91 μM, respectively. Compound 5a was found to arrest the cell cycle at the G2/M phase, increasing apoptotic cell death. The docking study also supported VEGFR-2 inhibitory activity as both compounds 5a and 5g displayed promising binding and interactions with the active sites of VEGFR-2 receptor (PDB: 3VHE) with docking scores - 9.355 and -7.758, respectively. All the compounds obeyed Lipinski's rule of five. Indoline-2,3-dione and thiazole have huge potential to be considered a steer combination approach for developing promising kinase inhibitors as cancer therapeutics.

Design, Synthesis, In Silico and In Vitro Studies of New Immunomodulatory Anticancer Nicotinamide Derivatives Targeting VEGFR-2.

VEGFR-2, the subtype receptor tyrosine kinase (RTK) responsible for angiogenesis, is expressed in various cancer cells. Thus, VEGFER-2 inhibition is an efficient approach for the discovery of new anticancer agents. Accordingly, a new set of nicotinamide derivatives were designed and synthesized to be VEGFR-2 inhibitors. The chemical structures were confirmed using IR, 1H-NMR, and 13C-NMR spectroscopy. The obtained compounds were examined for their anti-proliferative activities against the human cancer cell lines (HCT-116 and HepG2). VEGFR-2 inhibitory activities were determined for the titled compounds. Compound 8 exhibited the strongest anti-proliferative activities with IC50 values of 5.4 and 7.1 µM against HCT-116 and HepG2, respectively. Interestingly, compound 8 was the most potent VEGFR-2 inhibitor with an IC50 value of 77.02 nM (compare to sorafenib: IC50 = 53.65 nM). Treatment of HCT-116 cells with compound 8 produced arrest of the cell cycle at the G0–G1 phase and a total apoptosis increase from 3.05 to 19.82%—6.5-fold in comparison to the negative control. In addition, compound 8 caused significant increases in the expression levels of caspase-8 (9.4-fold) and Bax (9.2-fold), and a significant decrease in the Bcl-2 expression level (3-fold). The effects of compound 8 on the levels of the immunomodulatory proteins (TNF-α and IL-6) were examined. There was a marked decrease in the level of TNF-α (92.37%) compared to the control (82.47%) and a non-significant reduction in the level of IL-6. In silico docking, molecular dynamics simulations, and MM-PBSA studies revealed the high affinity, the correct binding, and the optimum dynamics of compound 8 inside the active site of VEGFR-2. Finally, in silico ADMET and toxicity studies indicated acceptable values of drug-likeness. In conclusion, compound 8 has emerged as a promising anti-proliferative agent targeting VEGFR-2 with significant apoptotic and immunomodulatory effects.

Nanogel-mediated drug delivery system for anticancer agent: pH stimuli responsive poly(ethylene glycol/acrylic acid) nanogel prepared by gamma irradiation

The popularity of nanogel as nano drug carrier lies in its adjustable physical properties, and the ability to encapsulate drug particles with improved properties is being developed to meet the diverse pH-sensitive nanogel for anticancer agent. Monitoring pH has been identified as an important diagnostic element during the treatment process. A pH-sensitive nanogel consisting of (PEG/PMAc) in the ratio of (50:50%) hasbeen cross-linkedby γ-irradiation techniques at an irradiation dose of 5 kGy. Compound 4 and its nanogel 5 were synthesized and assessed for their anticancer effects against HepG2, A549, MCF-7 and HCT-116 as dual VEGFR-2 and EGFR tyrosine kinases inhibitors. The molecular design was performed to investigate the binding mode of compound 4 with VEGFR-2 and EGFR receptors. Our compound 5 in nanogel showed enhanced anticancer activities against the four tested cancer cell lines and also showed higher inhibition activities against VEGFR-2 and EGFRT790M kinases than the derivative 4. Finally, our derivative 4 showed good in silico calculated ADMET profile. It was expected to show good GIT absorption in human, lower CNS side effects, no hepatotoxic actions and higher acute and oral chronic toxic doses in comparing to sorafenib and erlotinib. The obtained results showed that, our compound could be useful as a template for future design, optimization, adaptation and investigation to produce more potent and selective dual VEGFR-2/EGFRT790M inhibitors with higher anticancer activity.

Apatinib combined with chemotherapy versus single chemotherapy in HER-2 negative advanced breast cancer: A randomized, controlled, open-label phase II study.

1072 Background: Apatinib is an oral, highly potent tyrosine-kinase inhibitor targeting VEGFR2. A series of clinical studies have shown that anti-angiogenic drugs combined with chemotherapy enable to improve the efficacy of HER2-negative advanced/metastatic breast cancer(MBC). Methods: Patients with HER2-negative MBC with less than two lines of systemic therapy were enrolled in this open-label, controlled, phase II trial. Patients with measurable disease were randomly assigned, in a 1:1 ratio, to receive oral apatinib (250 mg once daily) combined with chemotherapy(A+CT) or chemotherapy(CT) alone (the physician’s choice) until disease progression or intolerable toxicity. The primary end point was progression-free survival(PFS), which was assessed by investigator and was analyzed on an intention-to-treat basis. Results: Between August 2017 and January 2021, of the 80 patients who underwent randomization, 40 were assigned to receive apatinib plus chemotherapy(A+CT) and 40 were assigned to receive standard therapy(CT). As of January 2022, 10 patient had not undergone response evaluation or dropout, 70 patients(36 patients in A+CT, 34 patients in CT were finally included with PFS events and 72 patients were included in safety set. Median PFS was significantly longer in A+CT than in CT (182 days vs 63 days; P = 0.043);The median PFS of TNBC subgroup (11 in A+CT group, 14 in CT) was longer in the aptinib group than in CT group (167 days vs 63 days; P = 0.637);The median PFS of HR+ subgroup(25 in apatinib group, 20 in chemotherapy group) was longer in the aptinib group than in CT group (259 days vs 56 days; P = 0.054);The median PFS of patients with liver metastases(19 in apatinib group, 17 in chemotherapy group) was longer in the aptinib group than in the CT group (151 days vs 54 days; P = 0.191); The severe adverse reactions (grade 3/4) were neutropenia(22.2% vs 13.9%), hypertension(11.1% vs 0.0%), leukopenia(8.3% vs 8,3%), hypokalemia(8.3% vs 2.8%), anemia(5.6% vs 11.1%), ALT(2.8% vs 8.3%), AST(0.0% vs 5.6%) in the apatinib group and the CT, respectively. Proteinuria did not occur in both groups. Treatment delay or dose reduction owing to adverse event was 16.7% and 11.1%, respectively. Treatment discontinuation owing to adverse event was 23.5% and 8.8%, respectively. Conclusions: Apatinib combined with chemotherapy showed a significant improvements in PFS and a manageable safety profile in HER2 negative MBC.

Infigratinib (BGJ 398), a Pan-FGFR Inhibitor, Targets P-Glycoprotein and Increases Chemotherapeutic-Induced Mortality of Multidrug-Resistant Tumor Cells.

The microtubule-targeting agents (MTAs) are well-known chemotherapeutic agents commonly used for therapy of a broad spectrum of human malignancies, exhibiting epithelial origin, including breast, lung, and prostate cancer. Despite the impressive response rates shortly after initiation of MTA-based therapy, the vast majority of human malignancies develop resistance to MTAs due to the different mechanisms. Here, we report that infigratinib (BGJ 398), a potent FGFR1-4 inhibitor, restores sensitivity of a broad spectrum of ABCB1-overexpressing cancer cells to certain chemotherapeutic agents, including paclitaxel (PTX) and doxorubicin (Dox). This was evidenced for the triple-negative breast cancer (TNBC), and gastrointestinal stromal tumor (GIST) cell lines, as well. Indeed, when MDR-overexpressing cancer cells were treated with a combination of BGJ 398 and PTX (or Dox), we observed a significant increase of apoptosis which was evidenced by an increased expression of cleaved forms of PARP, caspase-3, and increased numbers of Annexin V-positive cells, as well. Moreover, BGJ 398 used in combination with PTX significantly decreased the viability and proliferation of the resistant cancer cells. As expected, no apoptosis was found in ABCB1-overexpressing cancer cells treated with PTX, Dox, or BGJ 398 alone. Inhibition of FGFR-signaling by BGJ 398 was evidenced by the decreased expression of phosphorylated (i.e., activated) forms of FGFR and FRS-2, a well-known adaptor protein of FGFR signaling, and downstream signaling molecules (e.g., STAT-1, -3, and S6). In contrast, expression of MDR-related ABC-transporters did not change after BGJ 398 treatment, thereby suggesting an impaired function of MDR-related ABC-transporters. By using the fluorescent-labeled chemotherapeutic agent PTX-Alexa488 (Flutax-2) and doxorubicin, exhibiting an intrinsic fluorescence, we found that BGJ 398 substantially impairs their efflux from MDR-overexpressing TNBC cells. Moreover, the efflux of Calcein AM, a well-known substrate for ABCB1, was also significantly impaired in BGJ 398-treated cancer cells, thereby suggesting the ABCB1 as a novel molecular target for BGJ 398. Of note, PD 173074, a potent FGFR1 and VEGFR2 inhibitor failed to retain chemotherapeutic agents inside ABCB1-overexpressing cells. This was consistent with the inability of PD 173074 to sensitize Tx-R cancer cells to PTX and Dox. Collectively, we show here for the first time that BGJ 398 reverses the sensitivity of MDR-overexpressing cancer cells to certain chemotherapeutic agents due to inhibition of their efflux from cancer cells via ABCB1-mediated mechanism.

Design, synthesis, antitumor, and VEGFR-2 inhibition activities of novel 4-anilino-2-vinyl-quinazolines: Molecular modeling studies

The antitumor activity of newly synthesized 4-anilino-2-vinylquinazolines 8a-r was measured comparable to sorafenib as a standard drug. The 2-vinylquinazolines 8a-r were evaluated for their in vitro antitumor activity. The most active antitumor agents were subjected to in vitro VEGFR-2 inhibition and apoptotic inducing assay. Compounds 8 h, 8 l, and 8r showed potential antitumor activities with IC50 values of 4.92–14.37 μM relative to the reference drug, sorafenib (IC50 values of 5.47–9.18 μM). Compound 8 h possessed potential VEGFR-2 inhibitory activity (IC50 = 60.27 nM) compared to standard drug sorafenib (IC50 = 55.43 nM), whereas compound 8 l showed moderate inhibitory activity (IC50 = 93.50 nM). The most active compound, 8 h, exhibited total apoptosis with 36.24% on MCF-7 cells, more than the apoptotic effect provoked by sorafenib (32.46%) and the cell cycle arrested at a G1/S phase. Compound 8 h, a potent VEGFR-2 inhibitor, was docked into the VEGFR-2 binding pocket, where this compound showed binding interaction similar to co-crystallized inhibitor sorafenib.

Design and synthesis of new 2-oxoquinoxalinyl-1,2,4-triazoles as antitumor VEGFR-2 inhibitors

VEGFR-2 is a tyrosine kinase receptor for VEGFs that play a central role in tumor angiogenesis. The inhibition of the tyrosine kinase domain of VEGFR-2 has become an attractive therapeutic strategy in recent years for inhibiting tumor growth. In this study, a series of novel 2-oxoquinoxalinyl-1,2,4-triazoles were designed and synthesized as potential antitumor agents and VEGFR-2 inhibitors. Eight compounds in this series showed high growth inhibition against MCF-7 with GI50 ranging from 1.6 to 8.06 µM compared to staurosporine (GI50 = 8.39 µM) and sorafenib (GI50 = 11.20 µM). In addition, the results of the in vitro tyrosine kinase inhibition of VEGFR-2 revealed that most of the compounds possessed IC50 values in the sub-micromolar range. Compound 6g (IC50 = 0.037 µM) showed more potent VEGFR-2 inhibitory activity than sorafenib (IC50 = 0.045 µM). Furthermore, docking studies of the compounds with tyrosine kinase domain of VEGFR-2 (PDB ID: 4ASD) were performed. According to the results, 6g exhibited hydrogen bonding interactions with Glu885, Asp1046 and Cys919 amino acids in a similar way to sorafenib. Finally, physicochemical predictions of target compounds were examined in silico. The results revealed that all the compounds possessed promising drug-likeness profile.