Discovering the structure-activity relationships of different O-prenylated coumarin derivatives as effective anticancer agents in human cervical cancer cells

Cancer cell cycle heterogeneity as a critical determinant of therapeutic resistance

Intra-tumor heterogeneity is now arguably one of the most-studied topics in tumor biology, as it represents a major obstacle to effective cancer treatment. Since tumor cells are highly diverse at genetic, epigenetic, and phenotypic levels, intra-tumor heterogeneity can be assumed as an important contributing factor to the nullification of chemotherapeutic effects, and recurrence of the tumor. Based on the role of heterogeneous subpopulations of cancer cells with varying cell-cycle dynamics and behavior during cancer progression and treatment; herein, we aim to establish a comprehensive definition for adaptation of neoplastic cells against therapy. We discuss two parallel and yet distinct subpopulations of tumor cells that play pivotal roles in reducing the effects of chemotherapy: "resistant" and "tolerant" populations. Furthermore, this review also highlights the impact of the quiescent phase of the cell cycle as a survival mechanism for cancer cells. Beyond understanding the mechanisms underlying the quiescence, it provides an insightful perspective on cancer stem cells (CSCs) and their dual and intertwined functions based on their cell cycle state in response to treatment. Moreover, CSCs, epithelial-mesenchymal transformed cells, circulating tumor cells (CTCs), and disseminated tumor cells (DTCs), which are mostly in a quiescent state of the cell cycle are proved to have multiple biological links and can be implicated in our viewpoint of cell cycle heterogeneity in tumors. Overall, increasing our knowledge of cell cycle heterogeneity is a key to identifying new therapeutic solutions, and this emerging concept may provide us with new opportunities to prevent the dreadful cancer recurrence.

Comparative study of experimental and DFT calculations for 3-cinnamoyl 4-hydroxycoumarin derivatives

BACKGROUND

Computational research plays an important role in predicting the chemical and physical properties of biologically active compounds important in future structural modifications to improve or modify biological activity.

OBJECTIVE

This research focuses on quantum chemical and spectroscopic investigations properties of synthesized 4-hydroxycoumarin derivatives.

METHODS

Quantum chemical calculations were obtained using B3LYP, HF, and M06-2x level methods with the 6-31++G (d,p) basis set. Afterward, IR, 1H, 13C, UV-Visible experimentally parameters were compared with the results obtained using the B3LYP/6-31+G*(d) basis set of the molecules to be able to characterize the structures.

RESULTS

Based on the quantum chemical calculations compound with acetamido group on the phenyl ring is the most reactive, and compound with nitro substituent is the least reactive and the the strongest electrophile among tested compounds. With the exception of compounds with dimethylamino group, all other compounds have a pronounced tautomer between OH and C = O group. The calculated and experimental values are in agreement with each other.

CONCLUSION

The molecular structure in the ground state of six 3-cinnamoyl 4-hydroxycoumarin derivatives was optimized using density functional theory. The observed and computed values were compared and it can be concluded that the theoretical results were in good linear agreement with the experimental data.

Synthesis of Altissimacoumarin D and Other Prenylated Coumarins and Their Ability to Reverse the Multidrug Resistance Phenotype in Candida albicans

Azoles are the main antifungal agents employed in clinical practice to treat invasive candidiasis. Nonetheless, their efficacy is limited by fungal resistance mechanisms, mainly the overexpression of efflux pumps. Consequently, candidiasis has a worrisome death rate of 75%. One potential strategy to overcome efflux-mediated resistance is to inhibit this process. Ailanthus altissima is a Chinese tree that produces several active substances, including altissimacoumarin D. Due to the low yield of its extraction and the need to search for new drugs to treat candidiasis, this study aimed to synthesize altissimacoumarin D and its analogues, as well as evaluating their ability to reverse the resistance phenotype of Candida albicans. Coumarin isofraxidin was prepared via total synthesis through a solvent-free Knoevenagel condensation as the key step. Isofraxidin and other commercially available coumarins were alkylated with prenyl or geranyl groups to yield the natural product altissimacoumarin D and seven analogues. The antifungal activity of the coumarins and their ability to reverse the fungal resistance phenotype were assessed using microbroth methodologies. Toxicity was evaluated using erythrocytes and an in silico prediction. All compounds improved the antifungal activity of fluconazole by inhibiting efflux pumps, and ACS47 and ACS50 were the most active. None of the coumarins were toxic to erythrocytes. In silico predictions indicate that ACS47 and ACS50 may be safe for human use. ACS47 and ACS50 are promising candidates when used as adjuvants in the antifungal therapy against C. albicans-resistant strains.

Immune-Enhancing Effect of Heat-Treated Levilactobacillus brevis KU15159 in RAW 264.7 Cells

Probiotics are alive microbes that present beneficial to the human's health. They influence immune responses through stimulating antibody production, activating T cells, and altering cytokine expression. The probiotic characteristics of Levilactobacillus brevis KU15159 were evaluated on the tolerance and adherence to gastrointestinal conditions. L. brevis KU15159 was safe in a view of producing various useful enzymes and antibiotic sensitivity. Heat-treated L. brevis KU15159 increased production of nitric oxide (NO) and phagocytic activity in RAW 264.7 cells. In addition, heat-treated L. brevis KU15159 upregulated the expression of inducible nitric oxide synthase (iNOS) and proinflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, at protein as well as mRNA levels. In addition, the mitogen-activated protein kinase (MAPK) pathway, which regulates the immune system, was activated by heat-treated L. brevis KU15159. Therefore, L. brevis KU15159 exhibited an immune-enhancing effect by the MAPK pathway in macrophage.

Synthesis of 4-Hydroxycoumarin-Based Triazoles/Oxadiazoles as Novel Anticancer Agents

A series of novel 3-substituted-4-hydroxycoumarins 7 and 8 containing (5-aryl-1,3,4-oxadiazol-2-yl)thio or (4-amino-5-aryl-4H-1,2,4-triazol-3-yl)thio moieties have been synthesized and evaluated as anticancer agents. The in vitro MTT assay of compounds against hepatocellular carcinoma (HepG2), breast cancer (MCF7) cells, and a human colorectal adenocarcinoma cell line with epithelial morphology (HT29) indicated that the HepG2 cells had more susceptibility to the tested compounds. Indeed, all compounds (with the exception of 7b, 7c, 7g, and 8g) were more potent than the standard drug doxorubicin against HepG2 cells (IC₅₀ values=1.65-3.83 μM). Although, the better result was obtained with the oxadiazole analog 7h against HepG2 (IC₅₀ =1.65 μM), the N-amino-triazole derivatives 8c, 8e, 8f and, 8h with IC₅₀ values of 1.78-6.34 μM showed potent activity against all tested cell lines. The good drug-like properties and in vitro potency and selectivity of 4-hydroxycoumarins 8 make them as good leads for the development of new anticancer agents.

Angelol-A exerts anti-metastatic and anti-angiogenic effects on human cervical carcinoma cells by modulating the phosphorylated-ERK/miR-29a-3p that targets the MMP2/VEGFA axis

AIMS

Angelol-A (Ang-A), a kind of coumarins, is isolated from the roots of Angelica pubescens f. biserrata. However, AA exerts antitumor effects and molecular mechanism on cervical cancer cells is unknown.

MAIN METHODS

Cell viability was determined using the MTT assay, and the cell cycle phase was assessed by PI staining with flow cytometry. Ang-A-treated cells with/without Antago-miR-29a-3p (miR-29a-3p inhibitor) or U0126 (MEK inhibitor) were assessed for the expression of miR-29a-3p, in vitro migration/invasion, and angiogenesis using qRT-PCR, a chemotaxis assay, and tube formation assay, respectively. The expression of mitogen-activated protein kinases/MMP2/MMP9/VEGFA was determined by western blot analysis with applicable antibodies.

KEY FINDINGS

Ang-A significantly inhibited MMP2 and VEGFA expression, cell migration, and invasive motility in human cervical cancer cells. Conditioned medium inhibited tube formation in HUVECs. Ang-A principally inhibited invasive motility and angiogenesis by upregulating the expression of miR-29a-3p that targets the VEGFA-3' UTR. The role of miR-29a-3p was confirmed using Antago-miR-29a-3p, which reversed the Ang-A-inhibited expression of MMP2 and VEGFA, invasive motility, and angiogenesis in human cervical cancer cells. The ERK pathway was implicated in mediating the metastatic and angiogenic action of Ang-A. Combined treatment with Ang-A treated and U0126 exerted a synergistic inhibitory effect on the expression of MMP2 and VEGFA and the metastatic and angiogenic properties of human cervical cancer cells.

SIGNIFICANCE

These findings are the first to indicate that in human cervical cancer cells, Ang-A exerts anti-metastatic and anti-angiogenic effects via targeting the miR-29a-3p/MMP2/VEGFA axis, mediated through the ERK pathway.

The Anti-Cancer Potential of Heat-Killed Lactobacillus brevis KU15176 upon AGS Cell Lines through Intrinsic Apoptosis Pathway

Recent research has focused on the anti-cancer properties of Lactobacillus strains isolated from fermented foods. Their anti-cancer effects are caused by the apoptosis induction in cancer cells. However, sepsis, which can occur when cancer patients consume living organisms, can cause serious conditions in patients with reduced immunity because of cancer. Therefore, this study was conducted using heat-killed Lactobacillus brevis KU15176 (KU15176). To determine the relationship between inflammation and cancer, the anti-inflammatory effect of KU15176 was evaluated using a nitric oxide (NO) assay. Then, 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay was conducted to select cancer cells that showed the anti-proliferative effect of KU15176. Next, reverse transcription-polymerase chain reaction (RT-PCR), 4′,6-diamidino-2-phenylindole (DAPI) staining, flow cytometry, and caspase colorimetric assay were performed. As a result, it was confirmed that KU15176 could cause the increasing expression of apoptosis-related genes (Bax, caspase-3, and caspase-9), DNA breakage, effective apoptosis rate, and increased caspase activity in the human stomach adenocarcinoma (AGS) gastric cancer cell line. In conclusion, these results suggest a potential prophylactic effect of KU15176 against cancer.

8-Geranyloxycarbostyril as a potent 15-LOX-1 inhibitor showed great anti-tumor effects against prostate cancer

Carbostyrils are quinolone derivatives, with possible growth inhibition properties on cancer cells. Unlike many tumors, 15-Lipoxygenase-1 (15-LOX-1) is highly expressed in prostate cancer (PCa) cells and has oncogenic properties. Here, with the hypothesis that 6-, 7- and 8-geranyloxycarbostyril (GQ) have inhibitory properties on 15-LOX-1, their effects were assessed on PCa cells. Their cytotoxic effects were evaluated by MTT assay and mechanism of cell death was investigated using annexin V/PI staining. Finally, the anti-tumor properties of 8-GQ were assessed in immunocompromised C57BL/6 mice bearing human PCa cells. Accordingly, these compounds could effectively inhibit 15-LOX activity in PCa cells. MTT and flow cytometry tests confirmed their toxic effects on PCa cells, with no significant toxicity on normal cells, and apoptosis was the main mechanism of cell death. In vivo results indicated that use of 8-GQ at 50 mg/kg had stronger anti-tumor effects than 5 mg/kg cisplatin, with fewer side effects on normal tissues. Therefore, 8-GQ can be introduced as a potential drug candidate with 15-LOX-1 inhibitory potency, which can be effective in treatment of prostate cancer, and should be considered for further drug screening investigations.

Design, synthesis, and structure-activity relationship study of O-prenylated 3-acetylcoumarins as potent inhibitors of soybean 15-lipoxygenase

In this work, the design, synthesis, and structure-activity relationships of a novel array of geranyloxy and farnesyloxy 3-acetylcoumarins were reported as potent soybean 15-lipoxygenase inhibitors. Among the prepared coumarins, 7-farnesyloxy-3-acetylcoumarin (12b) was found to be the most potent inhibitor by IC50  = 0.68 μM while O-geranyl substituents at positions 5 and 6 of 3-acetylcoumarin (10a and 11a) were not inhibitors. Using docking studies, the binding affinity and the preferred pose of synthetic compounds were considered. It was found that lipoxygenase inhibitory activity and prenyl length chain were directly related. The hydrophobic cavity of the enzyme was more effectively occupied by the farnesyl moiety of the potent inhibitor 12b rather than other derivatives. Also, with this pose of farnesyl chain in 7-farnesyloxy-3-acetylcoumarins, the acetyl group could be directed to the hydrophilic pocket in the active site.

The antithrombotic activity of natural and synthetic coumarins

Thrombosis, which seriously endangers human health and life, is the leading cause of morbidity and mortality globally. Antithrombotic drugs can interfere with the occurrence and development of thrombotic diseases and play an important role in the treatment of thrombotic diseases. However, unsatisfactory efficacy and serious adverse effects of existing antithrombotic drugs increase the research for new, efficient and safer drugs. Natural and synthetic coumarins have been shown to possess antithrombotic activity, namely, anticoagulation and antiplatelet aggregation. Especially, coumarin-based warfarin, phenprocoumon and cloricromen have long been used in clinical treatment of thrombosis. Coumarin with low toxicity is the privileged structure for developing novel antithrombotic drugs with multiple mechanisms of action. The present review aims to compile current research on the development of coumarins against thrombosis, emphasizing the relationship between their chemical structures and therapeutic effectiveness. It is intended to provide promising ideas for the discovery of novel coumarin derivatives with high antithrombotic activity.

A Review of Auraptene as an Anticancer Agent

Auraptene is a bioactive monoterpene coumarin isolated from Citrus aurantium and Aegle marmelos that belong to the Rutaceae family. Auraptene can modulate intracellular signaling pathways that control cell growth, inflammation and apoptosis and can exert pharmacological properties such as anti-bacterial, anti-fungal, antileishmania and anti-oxidant activity. Auraptene had inhibitory and chemo-preventive effects on the proliferation, tumorigenesis and growth of several cancer cell lines through increase in the activity of glutathione S-transferase, formation of DNA adducts and reduction of the number of aberrant crypt foci. Auraptene exhibits anticancer effects via targeting different cell signaling pathways such as cytokines, genes modulating cellular proliferation, growth factors, transcription factors and apoptosis. The present review is a detailed survey of scientific researches on the cytotoxicity and anticancer activity of Auraptene on cancer cells and tumor bearing animals.

Investigating the effects of two novel 4-MMPB analogs as potent lipoxygenase inhibitors for prostate cancer treatment

Background

Lipoxygenases are one of the critical signaling mediators which can be targeted for human prostate cancer (PC) therapy. In this study, 4-methyl-2-(4-methylpiperazinyl)pyrimido[4,5-b]benzothiazine (4-MMPB) and its two analogs, 4-propyl-2-(4-methylpiperazinyl)pyrimido[4,5-b]benzothiazine (4-PMPB) and 4-ethyl-2-(4-methylpiperazinyl)pyrimido[4,5-b]benzothiazine (4-EMPB), were proposed to have anti-tumor properties in prostate cancer.

Methods

After synthesizing the compounds, cytotoxic effects of 4-MMPB and its two analogs against PC-3 cancerous and HDF normal cells were investigated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and then mechanism of cell death was assessed by flow cytometry. Finally, the anti-tumor effects of the mentioned compounds were investigated in an immunocompromised C57BL/6 mouse model.

Results

4-PMPB and 4-EMPB had similar anti-cancer effects on PC-3 cells as compared with 4-MMPB, while they were not effective on normal cells. Moreover, apoptosis and ferroptosis were the main mechanisms of induced cell death in these cancerous cells. Furthermore, in vivo results indicated that both analogs had similar anti-cancer effects as 4-MMPB, leading to delayed tumor growth without any noticeable side effects in weight loss and histological investigations.

Conclusion

Thus, our results suggest that specific targeting of lipoxygenases via 4-MMPB analogs can be considered as a treatment of choice for PC therapy, although it requires further investigations.

Coumarin Sulfonamides and Amides Derivatives: Design, Synthesis, and Antitumor Activity In Vitro

Coumarins possesses immeasurable antitumor potential with minimum side effects depending on the substitutions on the basic nucleus, which exhibits great prospects for antitumor drug development. In an attempt to develop novel antitumor candidates, a series of coumarin sulfonamides and amides derivatives were designed and synthetized. The majority of these derivatives showed good cytotoxic activity against MDA-MB-231 and KB cell lines, among which compound 9c was the most potent against MDA-MB-231 cells, with IC₅₀ value of 9.33 μM, comparable to 5-fluorouracil. Further investigation revealed that compound 9c had versatile properties against tumors, including inhibition of cell migration and invasion as well as inducing apoptosis. Reactive oxygen species (ROS) assay and western blotting analysis suggested that compound 9c promoted cancer cell apoptosis by increasing ROS levels and upregulating the expression of caspase-3 in MDA-MB-231 cells. These results indicated that compound 9c could be promising lead compound for further antitumor drug research.

Novel thiazoline–coumarin hybrid compounds containing sugar moieties: synthesis, biological evaluation and molecular docking study as antiproliferative agents

1,3-Thiadiazoline–coumarin hybrid compounds containing d-glucose and d-galactose moieties have the cytotoxicity against MCF-7, HepG2, HeLa, SK-Mel-2, and LU-1 cells and also EGFR and HER2 kinases. Molecular docking showed key roles in enhancing potency against both enzymes.

Crystal structure, chemical reactivity, kinetic and thermodynamic studies of new ligand derived from 4-hydroxycoumarin: Interaction with SARS-CoV-2

Currently, Covid-19 pandemic infects staggering number of people around the globe and causes a high rate of mortality. In order to fight this disease, a new coumarin derivative ligand (4-[(pyridin-3-ylmethyl) amino]-2H-chromen-2-one) (LTA) has been synthesized and characterized by single-crystal X-ray diffraction, NMR, ATR, UV-Visible and cyclic voltammetry. Chemical reactivity, kinetic and thermodynamic studies were investigated using DFT method. The possible binding mode between LTA and Main protease (Mpro) of SARS-CoV-2 and their reactivity were studied using molecular docking simulation. Single crystal X-ray diffraction showed that LTA crystallizes in a monoclinic system with P2 1  space group. The reactivity descriptors such as nucleophilic index confirm that LTA is more nucleophile, inducing complexation with binding species like biomolecules. The kinetic and thermodynamic parameters showed that the mechanism of crystal formation is moderately exothermic. The binding energy of the SARS-CoV-2/Mpro-LTA complex and the calculated inhibition constant using docking simulation showed that the active LTA molecule has the ability to inhibit SARS-CoV-2.

An Overview of Coumarin as a Versatile and Readily Accessible Scaffold with Broad-Ranging Biological Activities

Privileged structures have been widely used as an effective template for the research and discovery of high value chemicals. Coumarin is a simple scaffold widespread in Nature and it can be found in a considerable number of plants as well as in some fungi and bacteria. In the last years, these natural compounds have been gaining an increasing attention from the scientific community for their wide range of biological activities, mainly due to their ability to interact with diverse enzymes and receptors in living organisms. In addition, coumarin nucleus has proved to be easily synthetized and decorated, giving the possibility of designing new coumarin-based compounds and investigating their potential in the treatment of various diseases. The versatility of coumarin scaffold finds applications not only in medicinal chemistry but also in the agrochemical field as well as in the cosmetic and fragrances industry. This review is intended to be a critical overview on coumarins, comprehensive of natural sources, metabolites, biological evaluations and synthetic approaches.