New benzimidazole-oxadiazole derivatives as potent VEGFR-2 inhibitors: Synthesis, anticancer evaluation, and docking study.

We report herein, the design and synthesis of benzimidazole-oxadiazole derivatives as new inhibitors for vascular endothelial growth factor receptor-2 (VEGFR-2). The designed members were assessed for their in vitro anticancer activity against three cancer cell lines and two normal cell lines; A549, MCF-7, PANC-1, hTERT-HPNE and CCD-19Lu. Compounds 4c and 4d were found to be the most effective compounds against three cancer cell lines. Compounds 4c and 4d were then tested for their in vitro VEGFR-2 inhibitory activity, safety profiles, and selectivity indices using the normal hTERT-HPNE and CCD-19Lu cell lines. It was determined that compound 4c was the most effective and safe member of the produced chemical family. Vascular endothelial growth factor A (VEGFA) immunolocalizations of compounds 4c and 4d were evaluated relative to control by VEGFA immunofluorescence staining. Compounds 4c and 4d inhibited VEGFR-2 enzyme with half-maximal inhibitory concentration values of 0.475 ± 0.021 and 0.618 ± 0.028 µM, respectively. Molecular docking of the target compounds was carried out in the active site of VEGFR-2 (Protein Data Bank: 4ASD).

Discovery and Anticancer Screening of Novel Oxindole-Based Derivative Bearing Pyridyl Group as Potent and Selective Dual FLT3/CDK2 Kinase Inhibitor.

Protein kinases regulate cellular activities and make up over 60% of oncoproteins and proto-oncoproteins. Among these kinases, FLT3 is a member of class III receptor tyrosine kinase family which is abundantly expressed in individuals with acute leukemia. Our previous oxindole-based hit has a particular affinity toward FLT3 (IC50 = 2.49 µM) and has demonstrated selectivity towards FLT3 ITD-mutated MV4-11 AML cells, with an IC50 of 4.3 µM. By utilizing the scaffold of the previous hit, sixteen new compounds were synthesized and screened against NCI-60 human cancer cell lines. This leads to the discovery of a potent antiproliferative compound, namely 5l, with an average GI50 value against leukemia and colon cancer subpanels equalling 3.39 and 5.97 µM, respectively. Screening against a specific set of 10 kinases that are associated with carcinogenesis indicates that compound 5l has a potent FLT3 inhibition (IC50 = 36.21 ± 1.07 nM). Remarkably, compound 5l was three times more effective as a CDK2 inhibitor (IC50 = 8.17 ± 0.32 nM) compared to sunitinib (IC50 = 27.90 ± 1.80 nM). Compound 5l was further analyzed by means of docking and molecular dynamics simulation for CDK2 and FLT3 active sites which provided a rational for the observed strong inhibition of kinases. These results suggest a novel structural scaffold candidate that simultaneously inhibits CDK2 and FLT3 and gives encouragement for further development as a potential therapeutic for leukemia and colon cancer.

Synthesis of novel indol-3-acetamido analogues as potent anticancer agents, biological evaluation and molecular modeling studies.

Cannabinoids bind to cannabinoid receptors CB1 and CB2 and their antitumoral activity has been reported against some various cancer cell lines. Some synthetic cannabinoids possessing indole rings such as JWH-015 and JWH-133 particularly bind to the cannabinoid CB2 receptor and it was reported that they inhibit the proliferation and growth of various cancer cells without their psychoactive effects. However, the pharmacological action mechanisms of the cannabinoids are completely unknown. In this study, we report the synthesis of some new cannabinoidic novel indoles and evaluate their anticancer activity on various cancerous and normal cell lines (U87, RPMI 8226, HL60 and L929) using several cellular and molecular assays including MTT assay, real-time q-PCR, scratch assay, DAPI assay, Annexin V-PE/7AAD staining, caspase3/7 activity tests. Our findings indicated that compounds 7, 10, 13, 16, and 17 could reduce cell viability effectively. Compound 17 markedly increased proapoptotic genes (BAX, BAD, and BIM), tumor suppressor gene (p53) expression levels as well as the BAX/BCL-2 ratio in U87 cells. In addition, 17 inhibited cell migration. Based on these results, 17 was chosen for determining the mechanism of cell death in U87 cells. DAPI and Annexin V-7AAD staining results showed that 17 induced apoptosis, moreover activated caspase 3/7 significantly. Hence, compound 17, was selected as a lead compound for further pharmacomodulation. To rationalize the observed biological activities of 17, our study also included a comprehensive analysis using molecular docking and MD simulations. This integrative approach revealed that 17 fits tightly into the active site of the CB2 receptor and is involved in key interactions that may be responsible for its anti-proliferative effects.

Investigating Potential Cancer Therapeutics: Insight into Histone Deacetylases (HDACs) Inhibitions.

Histone deacetylases (HDACs) are enzymes that remove acetyl groups from ɛ-amino of histone, and their involvement in the development and progression of cancer disorders makes them an interesting therapeutic target. This study seeks to discover new inhibitors that selectively inhibit HDAC enzymes which are linked to deadly disorders like T-cell lymphoma, childhood neuroblastoma, and colon cancer. MOE was used to dock libraries of ZINC database molecules within the catalytic active pocket of target HDACs. The top three hits were submitted to MD simulations ranked on binding affinities and well-occupied interaction mechanisms determined from molecular docking studies. Inside the catalytic active site of HDACs, the two stable inhibitors LIG1 and LIG2 affect the protein flexibility, as evidenced by RMSD, RMSF, Rg, and PCA. MD simulations of HDACs complexes revealed an alteration from extended to bent motional changes within loop regions. The structural deviation following superimposition shows flexibility via a visual inspection of movable loops at different timeframes. According to PCA, the activity of HDACs inhibitors induces structural dynamics that might potentially be utilized to define the nature of protein inhibition. The findings suggest that this study offers solid proof to investigate LIG1 and LIG2 as potential HDAC inhibitors.

Synthesis, Anticancer Activity, and In Silico Modeling of Alkylsulfonyl Benzimidazole Derivatives: Unveiling Potent Bcl-2 Inhibitors for Breast Cancer.

A series of alkylsulfonyl 1H-benzo[d]imidazole derivatives were synthesized and evaluated for anticancer activity against human breast cancer cells, MCF-7 in vitro. The cytotoxic potential was determined using the xCELLigence real-time cell analysis, and expression levels of genes related to microtubule organization, tumor suppression, apoptosis, cell cycle, and proliferation were examined by quantitative real-time polymerase chain reaction. Molecular docking against Bcl-2 was carried out using AutoDock Vina, while ADME studies were performed to predict the physicochemical and drug-likeness properties of the synthesized compounds. The results revealed that compounds 23 and 27 were the most potent cytotoxic derivatives against MCF-7 cells. Gene expression analysis showed that BCL-2 was the most prominent gene studied. Treatment of MCF-7 cells with compounds 23 and 27 resulted in significant downregulation of the BCL-2 gene, with fold changes of 128 and 256, respectively. Docking analysis predicted a strong interaction between the compounds and the target protein. Interestingly, all of the compounds exhibit a higher binding affinity toward Bcl-2 than the standard drug (compound 27 vina score = -9.6 kcal/mol, vincristine = -6.7 kcal/mol). Molecular dynamics simulations of compounds 23 and 27 showed a permanent stabilization in the binding site of Bcl-2 for 200 ns. Based on Lipinski and Veber's filters, all synthesized compounds displayed drug-like characteristics. These findings suggest that compounds 23 and 27 were the most promising cytotoxic compounds and downregulated the expression of the BCL-2 gene. These derivatives could be further explored as potential candidates for the treatment of breast cancer.

New Benzimidazole-Triazole Derivatives as Topoisomerase I Inhibitors: Design, Synthesis, Anticancer Screening, and Molecular Modeling Studies.

In this study, we designed, synthesized, and evaluated a series of 1,2,4-triazole benzimidazoles for their cytotoxic effects against the A549, C6, and NIH3T3 cell lines. Additionally, these compounds were assessed for their inhibitory activity against DNA topoisomerase I, aiming to develop novel anticancer agents. The synthesized final compounds 4a-h were characterized using 1H NMR, 13C NMR, and HRMS. Among them, compounds 4b and 4h emerged as the most potent agents against the A549 cell line, exhibiting an IC50 value of 7.34 ± 0.21 µM and 4.56 ± 0.18 µM, respectively. These results were compared to standard drugs, doxorubicin (IC50 = 12.420 ± 0.5 µM) and Hoechst 33342 (IC50 = 0.422 ± 0.02 µM). Notably, all tested compounds displayed higher cytotoxicity toward A549 cells than C6 cells. Compounds 4b and 4h demonstrated significant inhibitory activity against topoisomerase I, highlighting their potential as lead compounds in anticancer therapy. Subsequent in silico molecular docking studies were conducted to elucidate the potential binding interactions of compounds 4b and 4h with the target enzyme topoisomerase I. Molecular dynamics studies also assessed and validated the binding affinity and stability. These studies confirmed the promising binding affinity of these compounds, reinforcing their status as lead candidates. According to DFT, compound 4b having the lower energy gap value (ΔE = 3.598 eV) is more chemically reactive than the others, which is consistent with significant inhibitory activity against topoisomerase I. Furthermore, in silico ADME profiles for compounds 4b and 4h were evaluated using SwissADME, providing insights into their pharmacokinetic properties.

Computational biology and in vitro studies for anticipating cancer-related molecular targets of sweet wormwood (Artemisia annua).

BACKGROUND: Cancer is one of the leading causes of death worldwide. Recently, it was shown that many natural extracts have positive effects against cancer, compared with chemotherapy or recent hormonal treatments. A. annua is an annual medicinal herb used in the traditional Chinese medicine. It has also been shown to inhibit the proliferation of various cancer cell lines. METHODS: Multi-level modes of action of A. annua constituents in cancer therapy were investigated using an integrated approach of network pharmacology, molecular docking, dynamic simulations and in-vitro cytotoxicity testing on both healthy and cancer cells. RESULTS: Network pharmacology-based analysis showed that the hit Artemisia annua constituents related to cancer targets were 3-(2-methylpropanoyl)-4-cadinene-3,11-diol, artemisinin G, O-(2-propenal) coniferaldehyde, (2-glyceryl)-O-coniferaldehyde and arteamisinin III, whereas the main cancer allied targets were NFKB1, MAP2K1 and AR. Sixty-eight significant signaling KEGG pathways with p < 0.01 were recognized, the most enriched of which were prostate cancer, breast cancer, melanoma and pancreatic cancer. Thirty-five biological processes were mainly regulated by cancer, involving cellular response to mechanical stimulus, positive regulation of gene expression and transcription. Molecular docking analysis of the top hit compounds against the most enriched target proteins showed that 3-(2-methylpropanoyl)-4-cadinene-3,11-diol and O-(2-propenal) coniferaldehyde exhibited the most stabilized interactions. Molecular dynamics simulations were performed to explain the stability of these two compounds in their protein-ligand complexes. Finally, confirmation of the potential anticancer activity was attained by in-vitro cytotoxicity testing of the extract on human prostate (PC-3), breast (MDA-MB-231), pancreatic (PANC-1) and melanoma (A375) cancerous cell lines. CONCLUSION: This study presents deeper insights into A. annua molecular mechanisms of action in cancer for the first time using an integrated approaches verifying the herb's value.

Phenotypic and Genetic Features that Differ Between Hereditary and Sporadic Melanoma: Results of a Preliminary Study from a Single Center from Turkey.

INTRODUCTION: Most melanoma patients under our supervision lack characteristic phenotypic features for melanoma. In contrast, history of cancers other than melanoma and early age at onset were common. This observation was in favor of hereditary melanoma. OBJECTIVES: To search for the phenotypic and genetic features that differ between sporadic and hereditary melanomas. METHODS: In order to reveal phenotypic features, detailed physical exam was conducted to all melanoma patients (N = 43) and for genetic features. CDKN2A and MC1R mutations were detected with Sanger sequencing method. Assignment to hereditary and sporadic groups was done according to the "melanoma cancer syndrome assessment tool". Patients who were diagnosed before the age of 50 were also assigned to the hereditary melanoma group. RESULTS: Thirty-one patients were assigned to the hereditary group and 12 to the sporadic group. Fair eye color was statistically significantly higher in the sporadic group (P = 0.000). CDKN2A was detected in only 1 patient in the hereditary group. MC1R mutations were found in 12 out of 13 (92.3%) in the hereditary group with a score =3 points, 13 out of 18 (72.2%) in the early age at onset group and 5 out of 12 (41.7%) in the sporadic group (P = 0.024). CONCLUSIONS: Incidence of CDKN2A mutations in our hereditary group is in accordance with the reported incidences from Mediterranean countries. The difference between the hereditary and sporadic groups in terms of MC1R mutations supports the idea that MC1R genetic testing might help to determine patients with higher risk for hereditary melanoma.

Epigallocatechin-3-Gallate Therapeutic Potential in Cancer: Mechanism of Action and Clinical Implications.

Cellular signaling pathways involved in the maintenance of the equilibrium between cell proliferation and apoptosis have emerged as rational targets that can be exploited in the prevention and treatment of cancer. Epigallocatechin-3-gallate (EGCG) is the most abundant phenolic compound found in green tea. It has been shown to regulate multiple crucial cellular signaling pathways, including those mediated by EGFR, JAK-STAT, MAPKs, NF-κB, PI3K-AKT-mTOR, and others. Deregulation of the abovementioned pathways is involved in the pathophysiology of cancer. It has been demonstrated that EGCG may exert anti-proliferative, anti-inflammatory, and apoptosis-inducing effects or induce epigenetic changes. Furthermore, preclinical and clinical studies suggest that EGCG may be used in the treatment of numerous disorders, including cancer. This review aims to summarize the existing knowledge regarding the biological properties of EGCG, especially in the context of cancer treatment and prophylaxis.

Pyrazolo[4,3-e]tetrazolo[1,5-b][1,2,4]triazine Sulfonamides as an Important Scaffold for Anticancer Drug Discovery-In Vitro and In Silico Evaluation.

Pyrazolo[4,3-e]tetrazolo[1,5-b][1,2,4]triazine sulfonamides (MM-compounds) are a relatively new class of heterocyclic compounds that exhibit a wide variety of biological actions, including anticancer properties. Here, we used caspase enzyme activity assays, flow cytometry analysis of propidium iodide (PI)-stained cells, and a DNA laddering assay to investigate the mechanisms of cell death triggered by the MM-compounds (MM134, -6, -7, and -9). Due to inconsistent results in caspase activity assays, we have performed a bromodeoxyuridine (BrdU) incorporation assay, colony formation assay, and gene expression profiling. The compounds' cytotoxic and pro-oxidative properties were also assessed. Additionally, computational studies were performed to demonstrate the potential of the scaffold for future drug discovery endeavors. MM-compounds exhibited strong micromolar (0.06-0.35 µM) anti-proliferative and pro-oxidative activity in two cancer cell lines (BxPC-3 and PC-3). Activation of caspase 3/7 was observed following a 24-h treatment of BxPC-3 cells with IC50 concentrations of MM134, -6, and -9 compounds. However, no DNA fragmentation characteristics for apoptosis were observed in the flow cytometry and DNA laddering analysis. Gene expression data indicated up-regulation of BCL10, GADD45A, RIPK2, TNF, TNFRSF10B, and TNFRSF1A (TNF-R1) following treatment of cells with the MM134 compound. Moreover, in silico studies indicated AKT2 kinase as the primary target of compounds. MM-compounds exhibit strong cytotoxic activity with pro-oxidative, pro-apoptotic, and possibly pro-necroptotic properties that could be employed for further drug discovery approaches.

Forecasting of potential anti-inflammatory targets of some immunomodulatory plants and their constituents using in vitro, molecular docking and network pharmacology-based analysis.

Most synthetic immunomodulatory medications are extremely expensive, have many disadvantages and suffer from a lot of side effects. So that, introducing immunomodulatory reagents from natural sources will have great impact on drug discovery. Therefore, this study aimed to comprehend the mechanism of the immunomodulatory activity of some natural plants via network pharmacology together with molecular docking and in vitro testing. Apigenin, luteolin, diallyl trisulfide, silibinin and allicin had the highest percentage of C-T interactions while, AKT1, CASP3, PTGS2, NOS3, TP53 and MMP9 were found to be the most enriched genes. Moreover, the most enriched pathways were pathways in cancer, fluid shear stress and atherosclerosis, relaxin signaling pathway, IL-17 signaling pathway and FoxO signaling pathway. Additionally, Curcuma longa, Allium sativum, Oleu europea, Salvia officinalis, Glycyrrhiza glabra and Silybum marianum had the highest number of P-C-T-P interactions. Furthermore, molecular docking analysis of the top hit compounds against the most enriched genes revealed that silibinin had the most stabilized interactions with AKT1, CASP3 and TP53, whereas luteolin and apigenin exhibited the most stabilized interactions with AKT1, PTGS2 and TP53. In vitro anti-inflammatory and cytotoxicity testing of the highest scoring plants exhibited equivalent outcomes to those of piroxicam.

Substances of Natural Origin in Medicine: Plants vs. Cancer.

Continuous monitoring of the population's health is the main method of learning about disease prevalence. National and international data draw attention to the persistently high rates of cancer incidence. This necessitates the intensification of efforts aimed at developing new, more effective chemotherapeutic and chemopreventive drugs. Plants represent an invaluable source of natural substances with versatile medicinal properties. Multidirectional activities exhibited by natural substances and their ability to modulate key signaling pathways, mainly related to cancer cell death, make these substances an important research direction. This review summarizes the information regarding plant-derived chemotherapeutic drugs, including their mechanisms of action, with a special focus on selected anti-cancer drugs (paclitaxel, irinotecan) approved in clinical practice. It also presents promising plant-based drug candidates currently being tested in clinical and preclinical trials (betulinic acid, resveratrol, and roburic acid).

PD-1/PD-L1 and DNA Damage Response in Cancer.

The application of immunotherapy for cancer treatment is rapidly becoming more widespread. Immunotherapeutic agents are frequently combined with various types of treatments to obtain a more durable antitumor clinical response in patients who have developed resistance to monotherapy. Chemotherapeutic drugs that induce DNA damage and trigger DNA damage response (DDR) frequently induce an increase in the expression of the programmed death ligand-1 (PD-L1) that can be employed by cancer cells to avoid immune surveillance. PD-L1 exposed on cancer cells can in turn be targeted to re-establish the immune-reactive tumor microenvironment, which ultimately increases the tumor's susceptibility to combined therapies. Here we review the recent advances in how the DDR regulates PD-L1 expression and point out the effect of etoposide, irinotecan, and platinum compounds on the anti-tumor immune response.

Doxorubicin-An Agent with Multiple Mechanisms of Anticancer Activity.

Doxorubicin (DOX) constitutes the major constituent of anti-cancer treatment regimens currently in clinical use. However, the precise mechanisms of DOX's action are not fully understood. Emerging evidence points to the pleiotropic anticancer activity of DOX, including its contribution to DNA damage, reactive oxygen species (ROS) production, apoptosis, senescence, autophagy, ferroptosis, and pyroptosis induction, as well as its immunomodulatory role. This review aims to collect information on the anticancer mechanisms of DOX as well as its influence on anti-tumor immune response, providing a rationale behind the importance of DOX in modern cancer therapy.

Vanillin-Based Indolin-2-one Derivative Bearing a Pyridyl Moiety as a Promising Anti-Breast Cancer Agent via Anti-Estrogenic Activity.

The structure-based design introduced indoles as an essential motif in designing new selective estrogen receptor modulators employed for treating breast cancer. Therefore, here, a series of synthesized vanillin-substituted indolin-2-ones were screened against the NCI-60 cancer cell panel followed by in vivo, in vitro, and in silico studies. Physicochemical parameters were evaluated with HPLC and SwissADME tools. The compounds demonstrated promising anti-cancer activity for the MCF-7 breast cancer cell line (GI = 6-63%). The compound with the highest activity (6j) was selective for the MCF-7 breast cancer cell line (IC50 = 17.01 µM) with no effect on the MCF-12A normal breast cell line supported by real-time cell analysis. A morphological examination of the used cell lines confirmed a cytostatic effect of compound 6j. It inhibited both in vivo and in vitro estrogenic activity, triggering a 38% reduction in uterine weight induced by estrogen in an immature rat model and hindering 62% of ER-α receptors in in vitro settings. In silico molecular docking and molecular dynamics simulation studies supported the stability of the ER-α and compound 6j protein-ligand complex. Herein, we report that indolin-2-one derivative 6j is a promising lead compound for further pharmaceutical formulations as a potential anti-breast cancer drug.

New2-((2-(2,4-dinitrophenyl)hydrazineeylidene) derivatives: design, synthesis, in silico, and in vitro anticancer studies.

A series of novel hydrazone compounds have been synthesized by the condensation of hydrazines and different substituted salicylaldehydes at a molar ratio of 1:1 in one step reaction and characterized by FT-IR, ESI-MS, 1H NMR, and single crystal x-ray diffraction. The crystal structure of the compound shows a trans configuration around the C = N bond and triclinic system with P -1/-p 1. Synthesized compounds were screened for cytotoxicity activities against A375 (melanoma), HT-29 (Colon), and A549 (lung) cancer cell lines. Among them, compound 2 exhibited the highest cytotoxic effect against the A375 cell line (IC50 = 0.30 µM) and HT-29 cell line (1.68 µM), compared to those of apatinib as a reference standard drug (0.28, 1.49 µM, respectively). The cytocompatibility assay on the L929 normal cell line and the hemolysis assay on human RBC were used to validate the non-toxic action. From DFT calculation, the various parameters such as HOMO-LUMO energies, Hirshfeld, and MEP have been studied. Furthermore, in silico molecular docking with three receptors was studied. Among four compounds, compound 2 has the lowest binding energy against cyclin dependent kinase (ΔGb = -9.3 kcal/mol). In addition to this, molecular dynamics (MD) simulation was also performed. Based on this study, these novel hydrazones can be considered a promising anticancer agent due to their potent cytotoxicity activities and computational analysis.Communicated by Ramaswamy H. Sarma.

Identification and in-vitro analysis of potential proteasome inhibitors targeting PSMß5 for multiple myeloma.

The proteasome subunit ß5 (PSMß5) is a chief target of proteasome inhibitors (PIs) for treatment of multiple myeloma (MM). The relevance of PSMß5 mutations and their functional impact on the development of resistance to PIs have been demonstrated recently. Therefore, this present study deals with an in-depth E-pharmacophore based screening and repurposing of FDA-approved drugs that could target PSMß5 for MM. Our molecular docking-based investigation revealed risedronate and zoledronate as potential alternative therapeutic molecules for targeting the PSMß5 gene. Risedronate and zoledronate displayed high binding affinity (-9.51 and -8.56 kcal/mol respectively) to PSMß5. Moreover, 100 ns molecular dynamics simulation analysis of docking complexes revealed risedronate and zoledronate with a superior binding free energies and stable interactions with PSMß5. The RMSD plot shows that the risedronate-PSMß5 (mean: 0.24 nm) and zoledronate-PSMß5 (mean: 0.25 nm) complexes are identical and stays stable until 100 ns. We further validated the activity of zoledronate in MM cell lines RPMI8226 and U266 where zoledronate showed significant anti-proliferative and apoptotic activity. Importantly, zoledronate showed an enhanced anti-proliferative activity when combined with bortezomib in MM cell lines. Thus, this study demonstrates that combining bortezomib with zoledronate could have a significant impact on reducing MM cell growth and can be an alternative strategy for treating MM.

Effect of isgin (Rheum ribes L.) on biochemical parameters, antioxidant activity and DNA damage in rats with obesity induced with high-calorie diet.

The present study was designed to investigate the effects of Rheum ribes L. plant root extracts on DNA damage, biochemical and antioxidant parameters in rats with experimental obesity induced with a high-calorie diet. The study groups were divided as "normal control(NC)", "obese control(OC)", "obese + Rheum ribes(OR1)(200 mg/kg)" and "obese + Rheum ribes (OR2)(400 mg/kg)". At the end of the application, rats were sacrificed and blood and tissue samples were obtained. According to the results obtained, the marker of DNA damage in tissues of 8-OHdG was determined to be significantly reduced in brain tissue of the OR1 and OR2 groups compared to the NC group. However, fluctuations were identified in the MDA activity, antioxidant defense system elements and serum biomarkers in tissues. In conclusion, Rheum ribes plant root extract ensured improvements in DNA damage in brain tissues and MDA levels and showed positive effects on antioxidant parameter activities in different tissues.

Discovery of oxindole-based FLT3 inhibitors as a promising therapeutic lead for acute myeloid leukemia carrying the oncogenic ITD mutation.

FMS-like tyrosine kinase 3 (FLT3) mutations occur in approximately 30% of acute myeloid leukemia (AML) patients. In the current study, the oxindole chemotype is employed as a structural motif for the design of new FLT3 inhibitors as potential hits for AML irradiation. Cell-based screening was performed with 18 oxindole derivatives and 5a-c inhibited 68%-73% and 83%-91% of internal tandem duplication (ITD)-mutated MV4-11 cell growth for 48- and 72-h treatments while only 0%-2% and 27%-39% in wild-type THP-1 cells. The most potent compound 5a inhibited MV4-11 cells with IC50 of 4.3 µM at 72 h while it was 8.7 µM in THP-1 cells, thus showing two-fold selective inhibition against the oncogenic ITD mutation. The ability of 5a to modulate cell death was examined. High-throughput protein profiling revealed low levels of the growth factors IGFBP-2 and -4 with the blockage of various apoptotic inhibitors such as Survivin. p21 with cellular stress mechanisms was characterized by increased expression of HSP proteins along with TNF-ß. Mechanistically, compounds 5a and 5b inhibited FLT3 kinase with IC50 values of 2.49 and 1.45 µM, respectively. Theoretical docking studies supported the compounds' ability to bind to the FLT3 ATP binding site with the formation of highly stable complexes as evidenced by molecular dynamics simulations. The designed compounds also provide suitable drug candidates with no violation of drug likeability rules.

Design, synthesis, molecular modeling, DFT, ADME and biological evaluation studies of some new 1,3,4-oxadiazole linked benzimidazoles as anticancer agents and aromatase inhibitors.

Breast cancer is the most frequent female cancer and second cause of cancer-related deaths among women around the world. Two thirds of breast cancer patients have hormone-dependent tumors, which is very likely be treated with hormonal therapy. Aromatase is involved in the biosynthesis of estrogen thus a critical target for breast cancer. In this study, in order to identify new aromatase enzyme inhibitors, a series of benzimidazole-1,3,4-oxadiazole derivatives were synthesized and characterized by 1H NMR, 13C NMR, and MS spectra analyses. In the in vitro anticancer assay, all the compounds tested anticancer activities using MTT-based assay against five cancer cell lines (MCF-7, A549, HeLa, C6, and HepG2). Among them, compound 5a exhibited the most potent activity with IC50 values of 5.165 ± 0.211 µM and 5.995 ± 0.264 µM against MCF-7 and HepG2 cell lines. Compound 5a was included in the BrdU test to determine the DNA synthesis inhibition effects for both cell types. Furthermore, compound 5c was also found to be more effective than doxorubicin on the HeLa cell line. The selectivity of anticancer activity was evaluated in NIH3T3 cell line. In vitro, enzymatic inhibition assays of aromatase enzyme were performed for compound 5a acting on the MCF-7 cell line. For compound 5a, in silico molecular docking and dynamics simulations against aromatase enzyme was performed to determine possible protein-ligand interactions and stability. DFT study was performed to evaluate the quantum mechanical and electronic properties of compound 5a. Finally, the theoretical ADME properties of the potential aromatase inhibitor compound 5a were analyzed by calculations.Communicated by Ramaswamy H. Sarma.