Antiproliferative and antiinflammatory coxib-combretastatin hybrids suppress cell cycle progression and induce apoptosis of MCF7 breast cancer cells

Megastigmanes isolated from Boehmeria nivea leaves and their immunomodulatory effect on IL-1β and IL-10 production in RAW264.7 macrophages

With the aim of isolating immunomodulatory compounds from the n-butanol extract of Boehmeria nivea leaves, nine megastigmane compounds were identified. Among these, the structure of the new compound 1, namely, "boehmegaside A", was established using NMR and HR-ESI-MS, and its absolute configurations were established through ECD calculations and DP4+ analysis using DFT-NMR chemical shift calculations. Furthermore, eight of these compounds were discovered for the first time in the Boehmeria genus, marking this the first report on megastigmane compounds isolated from this genus. Regarding their immunomodulatory activity, the isolated megastigmane compounds 3, 2, and 6 exhibited pro-inflammatory cytokine IL-1β secretion inhibitory activity. Compounds 3 and 6 significantly increased anti-inflammatory cytokine IL-10 secretion in LPS-activated RAW264.7 cells. Furthermore, the study on the mechanism of the immunomodulatory and other biological activities of megastigmane compounds through molecular docking simulations revealed that the planar structures of 3, 2, and 6 were critical in their ability to directly suppress TLR4 signalling. Instead, they attached to a nearby smooth area in TLR4. This interference likely disrupted the ability of TLR4 and MD-2 to form their primary contact interface and recognize LPS. These findings highlight the significant role of TLR4 in inflammation and immunity, indicating that these megastigmane compounds may be beneficial in treating various inflammatory disorders associated with immunological issues.

Design, synthesis, anti-inflammatory evaluation, and molecular docking studies of novel quinazoline-4(3H)-one-2-carbothioamide derivatives

In this paper, a series of novel quinazoline-4(3H)-one-2-carbothioamide derivatives (8a-p) were designed and synthesized via the Wilgerodt-Kindler reaction between 2-methylquinazoline-4-one 10 and amines using S8/DMSO as the oxidizing system. Their characteristics were confirmed by IR, NMR, HRMS spectra, and their melting point. These novel derivatives (8a-p) were evaluated for their anti-inflammatory activity by inhibiting NO production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophage cells. Compounds 8d (IC50 = 2.99 μM), 8g (IC50 = 3.27 μM), and 8k (IC50 = 1.12 μM) exhibited potent inhibition of NO production compared to the standard drug dexamethasone (IC50 = 14.20 μM). Compound 8a (IC50 = 13.44 μM) exhibited NO inhibition comparable to dexamethasone. Structure-activity relationship (SAR) studies indicated that the presence of both the thioamide functional group (NH-C[double bond, length as m-dash]S) directly attached to the phenyl ring containing halogen substituents (4-Cl, 8d), (4-Br, 8g) and (4-CF3, 8k), is responsible for the potent anti-inflammatory activity of these novel quinazolinone derivatives. Computational modeling studies revealed that compounds 8d, 8g, and 8k are potent inhibitors of TLR4 signaling through the formation of hydrophobic interactions and are stabilized by hydrogen bonds. Replacing the thioamide (8k) with an amide (8q) resulted in an 83-fold decrease in NO inhibitory potency. This highlights the important role of H-bonding involving the thioamide group. The structural shape difference results in favorable interactions of quinazolinones containing thioamide linkers compared to amide linkers to the target receptor. Furthermore, the ADMET profiles and physicochemical properties of these three lead compounds were predicted to meet the criteria for drug-like properties. Therefore, these compounds may be potential candidates for the treatment of many inflammatory diseases associated with immune disorders.

A novel life for antitumor combretastatins: Recent developments of hybrids, prodrugs, combination therapies, and antibody-drug conjugates

Since their discovery from natural sources, the potent cytotoxic effects of combretastatins were widely studied for the application in antitumor therapy. However, major pharmacokinetic issues as low water solubility and chemical instability of the double bond configuration prevented their use in therapy. A lot of efforts have been directed towards the search of novel strategies, allowing a safer use of combretastatins as anticancer agents. This review analyses the recent landscape in combretastatin research, characterized by the identification of hybrids, prodrugs, and novel combination treatments. Interestingly, the potent cytotoxic agent combretastatin A4 (CA4) was recently proposed as payload in the construction of novel antibody-drug conjugates (ADCs), allowing an efficient targeting of the cytotoxic agent to specific tumors.

New Cytotoxic Sesquiterpene Lactones from the Leaves of Tithonia Diversifolia and their Apoptosis Effect Evaluation in KB Cancer Cells

From the leaves of Tithonia diversifolia, nine sesquiterpenoids (1-9), including two new ones (tagitinin J (1) and tagitinin K (2)) were isolated and structurally determined. Their chemical structures were elucidated by extensive analyses of the HRESIMS and NMR spectral data, as well as comparison with the literature. All of the isolated compounds (except compounds 7-9) significantly exhibited cytotoxic activity against four human cancer cell lines (KB, HepG2, A549 and MCF7), with IC50 values ranging from 0.29-17.0 μM, which were in the same range as the positive control ellipticine or even lower. Further, the apoptosis induction effects of two new compounds 1 and 2 were also investigated and reported. While compound 2 did not induce the apoptosis in KB cells at test concentrations, compound 1 was found to possess anti-proliferative activity through concentration-dependently inducing cell cycle arrest at S phase, morphological changes, activation of caspase 3, and an increase in the early-stage apoptosis of KB cells at a concentration of 7.26 μM.

Current scenario of pyrazole hybrids with anti-breast cancer therapeutic applications

Breast cancer stands as the leading cause of cancer-related deaths among women globally, but current therapy is restricted to the serious adverse effects and multidrug resistance, necessitating the exploration of novel, safe, and efficient anti-breast cancer chemotherapeutic agents. Pyrazoles exhibit excellent potential for utilization as effective anti-breast cancer agents due to their ability to act on various biological targets. Particularly, pyrazole hybrids demonstrated the advantage of targeting multiple pathways, and some of them, which are exemplified by larotrectinib (pyrazolo[1,5-a]pyrimidine hybrid), can be applied for breast cancer therapy. Thus, pyrazole hybrids hold great promise as useful therapeutic interventions for breast cancer. The aim of this review is to summarize the current scenario of pyrazole hybrids with in vitro and/or in vivo anti-breast cancer potential, along with the modes of action and structure-activity relationships, covering articles published from 2020 to the present, to streamline the development of rational, effective and safe anti-breast cancer candidates.

Recent development of azole-sulfonamide hybrids with the anticancer potential

Cancer exhibits heterogeneity that enables adaptability and remains grand challenges for effective treatment. Chemotherapy is a validated and critically important strategy for the treatment of cancer, but the emergence of multidrug resistance which may lead to recurrence of disease or even death is a major hurdle for successful chemotherapy. Azoles and sulfonamides are important anticancer pharmacophores, and azole-sulfonamide hybrids have the potential to simultaneously act on dual/multiple targets in cancer cells, holding great promise to overcome drug resistance. This review outlines the current scenario of azole-sulfonamide hybrids with the anticancer potential, and the structure-activity relationships as well as mechanisms of action are also discussed, covering articles published from 2020 onward.

Recent Advancements in Refashioning of NSAIDs and their Derivatives as Anticancer Candidates

Inflammation is critical to the formation and development of tumors and is closely associated with cancer. Therefore, addressing inflammation and the mediators that contribute to the inflammatory process may be a useful strategy for both cancer prevention and treatment. Tumor predisposition can be attributed to inflammation. It has been demonstrated that NSAIDs can modify the tumor microenvironment by enhancing apoptosis and chemosensitivity and reducing cell migration. There has been a recent rise in interest in drug repositioning or repurposing because the development of innovative medications is expensive, timeconsuming, and presents a considerable obstacle to drug discovery. Repurposing drugs is crucial for the quicker and less expensive development of anticancer medicines, according to an increasing amount of research. This review summarizes the antiproliferative activity of derivatives of NSAIDs such as Diclofenac, Etodolac, Celecoxib, Ibuprofen, Tolmetin, and Sulindac, published between 2017 and 2023. Their mechanism of action and structural activity relationships (SARs) were also discussed to set the path for potential future repositioning of NSAIDs for clinical deployment in the treatment of cancer.

Chemical Profile and Biological Activities of Fungal Strains Isolated from Piper nigrum Roots: Experimental and Computational Approaches

The current report describes the chemical investigation and biological activity of extracts produced by three fungal strains Fusarium oxysporum, Penicillium simplicissimum, and Fusarium proliferatum isolated from the roots of Piper nigrum L. growing in Vietnam. These fungi were namely determined by morphological and DNA analyses. GC/MS identification revealed that the EtOAc extracts of these fungi were associated with the presence of saturated and unsaturated fatty acids. These EtOAc extracts showed cytotoxicity towards cancer cell lines HepG2, inhibited various microbacterial organisms, especially fungus Aspergillus niger and yeast Candida albicans (the MIC values of 50-100 μg/mL). In α-glucosidase inhibitory assay, they induced the IC₅₀ values of 1.00-2.53 μg/mL were better than positive control acarbose (169.80 μg/mL). The EtOAc extract of F. oxysporum also showed strong anti-inflammatory activity against NO production and PGE-2 level. Four major compounds linoleic acid (37.346 %), oleic acid (27.520 %), palmitic acid (25.547 %), and stearic acid (7.030 %) from the EtOAc extract of F. oxysporum were selective in molecular docking study, by which linoleic and oleic acids showed higher binding affinity towards α-glucosidase than palmitic and stearic acids. In subsequent docking assay with inducible nitric oxide synthase (iNOS), palmitic acid, oleic acid and linoleic acid could be moderate inhibitors.

Flavonoids as Modulators of Potassium Channels

Potassium channels are widely distributed integral proteins responsible for the effective and selective transport of K+ ions through the biological membranes. According to the existing structural and mechanistic differences, they are divided into several groups. All of them are considered important molecular drug targets due to their physiological roles, including the regulation of membrane potential or cell signaling. One of the recent trends in molecular pharmacology is the evaluation of the therapeutic potential of natural compounds and their derivatives, which can exhibit high specificity and effectiveness. Among the pharmaceuticals of plant origin, which are potassium channel modulators, flavonoids appear as a powerful group of biologically active substances. It is caused by their well-documented anti-oxidative, anti-inflammatory, anti-mutagenic, anti-carcinogenic, and antidiabetic effects on human health. Here, we focus on presenting the current state of knowledge about the possibilities of modulation of particular types of potassium channels by different flavonoids. Additionally, the biological meaning of the flavonoid-mediated changes in the activity of K+ channels will be outlined. Finally, novel promising directions for further research in this area will be proposed.

Target Design of Novel Histone Deacetylase 6 Selective Inhibitors with 2-Mercaptoquinazolinone as the Cap Moiety

Epigenetic alterations found in all human cancers are promising targets for anticancer therapy. In this sense, histone deacetylase inhibitors (HDACIs) are interesting anticancer agents that play an important role in the epigenetic regulation of cancer cells. Here, we report 15 novel hydroxamic acid-based histone deacetylase inhibitors with quinazolinone core structures. Five compounds exhibited antiproliferative activity with IC50 values of 3.4-37.8 µM. Compound 8 with a 2-mercaptoquinazolinone cap moiety displayed the highest antiproliferative efficacy against MCF-7 cells. For the HDAC6 target selectivity study, compound 8 displayed an IC50 value of 2.3 µM, which is 29.3 times higher than those of HDAC3, HDAC4, HDAC8, and HDAC11. Western blot assay proved that compound 8 strongly inhibited tubulin acetylation, a substrate of HDAC6. Compound 8 also displayed stronger inhibition activity against HDAC11 than the control drug Belinostat. The inhibitory mechanism of action of compound 8 on HDAC enzymes was then explored using molecular docking study. The data revealed a high binding affinity (-7.92 kcal/mol) of compound 8 toward HDAC6. In addition, dock pose analysis also proved that compound 8 might serve as a potent inhibitor of HDAC11.

Orientin, a Bio-Flavonoid from Trigonella hamosa L., Regulates COX-2/PGE-2 in A549 Cell Lines via miR-26b and miR-146a

Cancer is a severe health condition and considered one of the major healthcare issues and is in need of innovative strategy for a cure. The current study aimed to investigate the chemical profile of Trigonella hamosa L. and a potential molecular approach to explain its regulation in cancer progression through an inflammatory mediator (COX-2) in A549 non-small lung cancer cell lines via in silico, mechanistic and molecular aspects. T. hamosa was extracted and then subjected to a CCK-8 cell viability assay in different cancer cell lines including MDA-MB-231, A549 and HCT-116. Total extract was subjected to several chromatographic techniques to yield orientin (OT); the structure was elucidated by inspection of NMR spectroscopic data. To achieve anticancer effects of OT, a cell viability assay using a CCK-8 kit, immunoprecipitation by Western blot, cell migration using a wound healing assay, cell invasion using a Matrigel-Transwell assay, apoptosis by AO/EB dual staining, flow cytometric analysis and DAPI staining, a silenced COX-2 model to determine PGE-2 production and real-time PCR and Western blot of BCL-2, CYP-1A1, iNOS and COX-2 markers were carried out. The results demonstrated that OT decreased the cell proliferation and controlled cell migration and invasive properties. OT destabilized the COX-2 mRNA and downregulated its expression in A549 cell lines. Virtual binding showed interaction (binding energy −10.43) between OT and COX-2 protein compared to the selective COX-2 inhibitor celecoxib (CLX) (binding energy −9.4). The OT-CLX combination showed a superior anticancer effect. The synergistic effect of OT-CLX combination was noticed in controlling the migration and invasion of A549 cell lines. OT-CLX downregulated the expression of BCL-2, iNOS and COX-2 and activated the proapoptotic gene CYP-1A1. OT mitigated the COX-2 expression via upregulation of miR-26b and miR-146a. Interestingly, COX-2-silenced transfected A549 cells exhibited reduced expression of miR-26b and miR-146a. The findings confirmed the direct interaction of OT with COX-2 protein. PGE-2 expression was quantified in both naïve and COX-2-silenced A549 cells. OT downregulated the release of PGE-2 in both tested conditions. These results confirmed the regulatory effect of OT on A549 cell growth in a COX-2-dependent manner. OT activated apoptosis via activation of CYP-1A1 expression in an independent manner. These results revealed that the OT-CLX combination could serve as a potential synergistic treatment for effective inflammatory-mediated anticancer strategies.

Bannaxanthone E Induced Cell-Cycle Arrest and Apoptosis in Human Lung Cancer Cell Line

The anti-cancer activity of bannaxanthone E isolated from Garcinia mckeaniana leaves was assessed through a flow cytometric method on human lung SK-LU-1 cancer cells, including cell cycle changes and induction of cell apoptosis. Treatment with bannaxanthone E led to the suppression of cell cycle progression at the G2/M phase to 19.6% at 4 µM, and induced apoptosis via cell morphological changes, increased the fluorescence signal in caspase-3/7 activation, and accumulation of apoptotic cells in the SK-LU-1 line at 4 µM to 25.7%.

Chemical Constituents of Eupatorium japonicum and Anti-Inflammatory, Cytotoxic, and Apoptotic Activities of Eupatoriopicrin on Cancer Stem Cells

Eupatorium japonicum Thunb. of the plant family Asteraceae is a popular traditional herb in Vietnam. However, its chemical constituents as well as bioactive principles have not been investigated yet. We investigated the phytochemistry of E. japonicum in Vietnam and isolated seventeen compounds (1–17) including phytosterols, terpenoids, phenolic acids, flavonoids, fatty alcohols, and fatty acids. They were structurally determined by MS and NMR analysis. Except for compounds 6 and 12, all the other compounds were identified for the first time from E. japonicum. Since many sesquiterpene lactones with α-methylene γ-lactone ring are reported as anti-inflammatory and anticancer agents, eupatoriopicrin (10), 1-hydroxy-8-(4,5-dihydroxytigloyloxy)eudesma-4(15),11(13)-dien-6,12-olide (11) were selected among the isolates for biological assays. Compound 10 was identified as the main bioactive sesquiterpene lactone of E. japonicum showing its potent anti-inflammatory and cytotoxic activity through inhibiting NO production and the growth of HepG2 and MCF-7 human cancer cell lines. For the first time, eupatoriopicrin (10) was demonstrated to strongly inhibit NTERA-2 human cancer stem cell (CSC) line in vitro. It is noticeable that the cytotoxicity of eupatoriopicrin against NTERA-2 cells is mediated by its apoptosis-inducing capability of 10 as demonstrated by the results of Hoechst 33342 staining, flow cytometry apoptosis analysis, and caspase-3 activity assays. The biological activities of the main bioactive constituents 1–7, 10, 12, and 15 supported the reported anti-inflammatory and anticancer properties of extracts from E. japonicum.