Cinnamic acid induces apoptotic cell death and cytoskeleton disruption in human melanoma cells

Study of Host-Guest Interaction and In Vitro Neuroprotective Potential of Cinnamic Acid/Randomly Methylated β-Cyclodextrin Inclusion Complex

Cinnamic acid (CA) has many beneficial effects on human health. However, its poor water solubility (0.23 g/L, at 25 °C) is responsible for its poor bioavailability. This drawback prevents its clinical use. To overcome the solubility limits of this extraordinary natural compound, in this study, we developed a highly water-soluble inclusion complex of CA with randomly methylated-β-cyclodextrin (RAMEB). The host-guest interaction was explored in liquid and solid states by UV-Vis titration, phase solubility analysis, FT-IR spectroscopy, and 1H-NMR. Additionally, molecular modeling studies were carried out. Both experimental and theoretical studies revealed a 1:1 CA/RAMEB inclusion complex, with a high apparent stability constant equal to 15,169.53 M-1. The inclusion complex increases the water solubility of CA by about 250-fold and dissolves within 5 min. Molecular modeling demonstrated that CA inserts its phenyl ring into the RAMEB cavity with its propyl-2-enoic acid tail leaning from the wide rim. Finally, a biological in vitro study of the inclusion complex, compared to the free components, was performed on the neuroblastoma SH-SY5Y cell line. None of them showed cytotoxic effects at the assayed concentrations. Of note, the pretreatment of SH-SY5Y cells with CA/RAMEB at 10, 30, and 125 µM doses significantly counteracted the effect of the neurotoxin MPP+, whilst CA and RAMEB alone did not show any neuroprotection. Overall, our data demonstrated that inclusion complexes overcome CA solubility problems, supporting their use for clinical applications.

Phytochemical profile and determination of cytotoxicity, acute oral toxicity, genotoxicity, and mutagenicity of aqueous and ethanolic extracts of Pseudobombax marginatum (A. St.-Hil.) A. Robyns

Pseudobombax marginatum, popularly known as "embiratanha," is widely used by traditional communities as anti-inflammatory and analgesic agent. This study aimed to determine the phytochemical profile as well as cytotoxicity, acute oral toxicity, genotoxicity, and mutagenicity attributed to exposure to aqueous (AqEx) and ethanolic (EtEx) extracts of embiratanha bark. Phytochemical screening was conducted using thin-layer chromatography (TLC). Cell viability was analyzed using MTT assay with human mammary gland adenocarcinoma (MDA-MB-231) and macrophage (J774A.1) cell lines, exposed to concentrations of 12.5, 25, 50, or 100 µg/ml of either extract. For acute oral toxicity, comet assay and micronucleus (MN) tests, a single dose of 2,000 mg/kg of either extract was administered orally to Wistar rats. TLC analysis identified classes of metabolites in the extracts, including cinnamic acid derivatives, flavonoids, hydrolyzable tannins, condensed tannins, coumarins, and terpenes/steroids. In the cytotoxicity assay, the varying concentrations of extracts derived from embiratanha induced no significant alterations in the viability of MDA-MB-231 cells. The lowest concentration of EtEx significantly increased macrophage J774A.1 viability. However, the higher concentrations of AqEx markedly lowered macrophage J774A.1 viability. Animals exhibited no toxicity in the parameters analyzed in acute oral toxicity, comet assay, and MN tests. Further, EtEx promoted a significant reduction in DNA damage index and DNA damage frequency utilizing the comet assay, while the group treated with AqEx exhibited no marked differences. Thus, data demonstrated that AqEx or EtEx of embiratanha may be considered safe at a dose of 2,000 mg/kg orgally under our experimental conditions tested.

Zinc oxide nanoparticles functionalized with cinnamic acid for targeting dental pathogens receptor and modulating apoptotic genes in human oral epidermal carcinoma KB cells

BACKGROUND

Oral diseases are often attributed to dental pathogens such as S. aureus, S. mutans, E. faecalis, and C. albicans. In this research work, a novel approach was employed to combat these pathogens by preparing zinc oxide nanoparticles (ZnO NPs) capped with cinnamic acid (CA) plant compounds.

METHODS

The synthesized ZnO-CA NPs were characterized using SEM, FTIR, and XRD to validate their composition and structural features. The antioxidant activity of ZnO-CA NPs was confirmed using DPPH and ABTS free radical scavenging assays. The antimicrobial effects of ZnO-CA NPs were validated using a zone of inhibition assay against dental pathogens. Autodock tool was used to identify the interaction of cinnamic acid with dental pathogen receptors.

RESULTS

ZnO-CA NPs exhibited potent antioxidant activity in both DPPH and ABTS assays, suggesting their potential as powerful antioxidants. The minimal inhibitory concentration of ZnO-CA NPs against dental pathogens was found 25 µg/mL, indicating their effective antimicrobial properties. Further, ZnO-CA NPs showed better binding affinity and amino acid interaction with dental pathogen receptors. Also, the ZnO-CA NPs exhibited dose-dependent (5 µg/mL, 15 µg/mL, 25 µg/mL, and 50 µg/mL) anticancer activity against Human Oral Epidermal Carcinoma KB cells. The mechanism of action of apoptotic activity of ZnO-CA NPs on the KB cells was identified through the upregulation of BCL-2, BAX, and P53 genes.

CONCLUSIONS

This research establishes the potential utility of ZnO-CA NPs as a promising candidate for dental applications. The potent antioxidant, anticancer, and effective antimicrobial properties of ZnO-CA NPs make them a valuable option for combating dental pathogens.

Effect of Petiveria alliacea Extracts on Metabolism of K562 Myeloid Leukemia Cells

Previously, studies have shown that leukemic cells exhibit elevated glycolytic metabolism and oxidative phosphorylation in comparison to hematopoietic stem cells. These metabolic processes play a crucial role in the growth and survival of leukemic cells. Due to the metabolic plasticity of tumor cells, the use of natural products has been proposed as a therapeutic alternative due to their ability to attack several targets in tumor cells, including those that could modulate metabolism. In this study, the potential of Petiveria alliacea to modulate the metabolism of K562 cell lysates was evaluated by non-targeted metabolomics. Initially, in vitro findings showed that P. alliacea reduces K562 cell proliferation; subsequently, alterations were observed in the endometabolome of cell lysates treated with the extract, mainly in glycolytic, phosphorylative, lipid, and amino acid metabolism. Finally, in vitro assays were performed, confirming that P. Alliacea extract decreased the oxygen consumption rate and intracellular ATP. These results suggest that the anti-tumor activity of the aqueous extract on the K562 cell line is attributed to the decrease in metabolites related to cell proliferation and/or growth, such as nucleotides and nucleosides, leading to cell cycle arrest. Our results provide a preliminary part of the mechanism for the anti-tumor and antiproliferative effects of P. alliacea on cancer.

Aqueous Extract of Cinnamon (Cinnamomum spp.): Role in Cancer and Inflammation

Cinnamon (Cinnamomum spp.; family Lauraceae), a plant widely used as a spice and flavoring agent and in the perfume industry, has high therapeutic value. However, the components and chemical properties of cinnamon extracts vary depending on the part of the plant, the method, and the solvent used for extraction. Green extraction methods using safe and green solvents have gained increased interest in recent years. Water is an environmentally friendly and safe green solvent widely used for preparing cinnamon extracts. This review focuses on the various preparation techniques for the aqueous extract of cinnamon, its major bioactive components, and their beneficial roles in different pathological conditions, specifically cancer and inflammation. The aqueous extract of cinnamon contains several bioactive compounds, such as cinnamaldehyde, cinnamic acid, and polyphenols, and exerts anticancer and anti-inflammatory properties by altering key apoptotic and angiogenic factors. The whole extract is a better anticancer and anti-inflammatory agent than the purified fractions, indicating a synergistic effect between various components. Studies have indicated that aqueous cinnamon extract has immense therapeutic potential, and to better understand its synergistic effects, extensive characterization of the aqueous extract and its potential to be used with other therapies should be explored.

HPLC Analysis and Molecular Docking Study of Myoporum serratum Seeds Extract with Its Bioactivity against Pathogenic Microorganisms and Cancer Cell Lines

Natural constituents have been utilized to avoid humanity from various diseases, such as microbial infection and cancer, over several decades due to bioactive compounds. Myoporum serratum seeds extract (MSSE) was formulated via HPLC for flavonoid and phenolic analysis. Moreover, antimicrobial via well diffusion method, antioxidant via 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method, anticancer activities against HepG-2 cells (human hepatocellular cancer cell line), and MCF-7 cells (human breast cancer cell line), and molecular docking of the main detected flavonoid and phenolic compounds with the cancer cells were performed. The phenolic acids, including cinnamic acid (12.75 µg/mL), salicylic acid (7.14 µg/mL), and ferulic (0.97 µg/mL), while luteolin represents the main detected flavonoid with a concentration of 10.74 µg/mL, followed by apegenin 8.87 µg/mL were identified in MSSE. Staphylococcus aureus, Bacillus subtilis, Proteus vulgaris, and Candida albicans were inhibited by MSSE with 24.33, 26.33, 20.67, and 18.33 mm of inhibition zone, respectively. MSSE exhibited a low inhibition zone of 12.67 mm against Escherichia coli while showing no inhibitory activity against Aspergillus fumigatus. The values of MIC ranged from 26.58 to 136.33 µg/mL for all tested microorganisms. MBC/MIC index and cidal properties were attributed to MSSE for all tested microorganisms except E. coli. MSSE demonstrated anti-biofilm 81.25 and 50.45% of S. aureus and E. coli, respectively. IC₅₀ of the antioxidant activity of MSSE was 120.11 µg/mL. HepG-2 and MCF-7 cell proliferation were inhibited with IC₅₀ 140.77 ± 3.86 µg/mL and 184.04 µg/mL, respectively. Via Molecular docking study, luteolin and cinnamic acid have inhibitory action against HepG-2 and MCF-7 cells, supporting the tremendous anticancer of MSSE.

7-Geranyloxycinnamic Acid Isolated from Melicope lunu-ankenda Leaves Perturbs Colon Cancer and Breast Cancer Cell Lines' Growth via Induction of Apoptotic Pathway

Globally, breast cancer is the most prevalent form of cancer in women and there is a need for alternative therapies such as plant-derived compounds with low systemic toxicity and selective toxicity to cancer cells. The aim of this study is to assess the cytotoxicity effects of 7-geranyloxycinnamic acid isolated from leaves of Melicope lunu-ankenda, a traditional medicinal plant, on the human breast cancer cell lines. Dried leaf powder was used for the preparation of different crude extracts using different solvents of increasing order of polarity. The structure of the isolated compound from the petroleum ether extract was elucidated by ¹H and ¹³C NMR, LC-MS, and DIP-MS spectroscopy. The cytotoxic activity of the crude extract and 7-geranyloxycinnamic acid analyzed using MTT assay. Apoptotic analysis was evaluated using Annexin V-PI staining, AO/PI staining, intracellular ROS measurement, and measurement of activities of caspases 3/7, 8, and 9. Crude extracts and the isolated pure compound showed significant cytotoxicity against tested cancer cell lines. 7-geranyloxycinnamic acid was found to exert significant cytotoxic effects against breast cancer cell lines such as the MCF-7 and MDA-MB-231 cell lines. The cytotoxic effects are attributed to its ability to induce apoptosis via accumulation of ROS and activation of caspases in both breast cancer cell lines. The pure compound, 7-geranyloxycinnamic acid isolated from the leaves of M. lunu-ankenda, can exert significant cytotoxic effects against breast cancer cell lines without affecting the normal cells.

In Vitro Anti-Colorectal Cancer and Anti-Microbial Effects of Pinus roxburghii and Nauplius graveolens Extracts Modulated by Apoptotic Gene Expression

The use of phytochemicals is gaining increasing attention for treating cancer morbidity with minimal burden side effects. This study evaluated the cytotoxicity and antimicrobial activities of Pinus roxburghii branch (P. roxburghii) and Nauplius graveolens (N. graveolens) extracts in vitro. Cell viability was estimated using MTT assay. DNA fragmentation was determined to detect apoptotic pathway initiation. Mechanistically, the apoptotic pathway was tracked by estimating the relative mRNA expression levels of the Bcl-2, Bax, Cas3, NF-κB, and PI3k genes by qRT-PCR. P. roxburghii exhibited moderate antioxidant activity, while N. graveolens possessed highly significant (p < 0.05) scavenging activity against DPPH and ABTS assays. HPLC analysis demonstrated that catechin and chlorogenic acid were the predominant polyphenolic compounds in P. roxburghii and N. graveolens, respectively. The P. roxburghii and N. graveolens extracts inhibited the viability of HCT-116 cells with IC50 values of 30.6 µg mL−1 and 26.5 µg mL−1, respectively. DNA fragmentation analysis showed that the proposed extracts induced apoptosis in HCT-116 cells. Moreover, the IC50 doses of the selected extracts significantly (p < 0.05) upregulated Bax and cleaved Cas-3, and downregulated Bcl-2, NF-κB, and PI3k genes versus the GAPDH gene as a housekeeping gene in comparison to the control group. The Bax/Bcl-2 ratio was raised upon treatment. The mentioned extracts exhibited antimicrobial action against all tested bacteria and fungi. The highest antibacterial effect was recorded against E. coli, with inhibition zones of 12.0 and 11.2 mm for P. roxburghii and N. graveolens, respectively. On the other hand, the highest antifungal action was registered for Penicillium verrucosum and A. niger, with inhibition zones of 9.8 and 9.2 mm for the tested extracts, respectively. In conclusion, the outcomes of this study indicate that P. roxburghii and N. graveolens extracts could potentially be used as anticancer, antibacterial, and antifungal agents.

Integrated network pharmacology and serum metabolomics approach deciphers the anti-colon cancer mechanisms of Huangqi Guizhi Wuwu Decoction

Huangqi Guizhi Wuwu Decoction (HGWD), as a classic Chinese herbal decoction, has been widely used in treating various diseases for hundreds of years. However, systematically elucidating its mechanisms of action remains a great challenge to the field. In this study, taking advantage of the network pharmacology approach, we discovered a potential new use of HGWD for patients with colon cancer (CC). Our in vivo result showed that orally administered HGWD markedly inhibited the growth of CC xenografts in mice. The subsequent enrichment analyses for the core therapeutic targets revealed that HGWD could affect multiple biological processes involving CC growth, such as metabolic reprogramming, apoptosis and immune regulation, through inhibiting multiple cell survival-related signalings, including MAPK and PI3K-AKT pathways. Notably, these in silico analysis results were most experimentally verified by a series of in vitro assays. Furthermore, our results based on serum metabolomics showed that the lipid metabolic pathways, including fatty acid biosynthesis and cholesterol metabolism, play key roles in delivery of the anti-CC effect of HGWD on tumor-bearing mice, and that cytochrome P450 family 2 subfamily E member 1 (CYP2E1) is a potential therapeutic target. Together, our integrated approach reveals a therapeutic effect of HGWD on CC, providing a valuable insight into developing strategies to predict and interpret the mechanisms of action for Chinese herbal decoctions.

Flavonoid and Phenolic Acid Profiles of Dehulled and Whole Vigna subterranea (L.) Verdc Seeds Commonly Consumed in South Africa

Bambara groundnut (BGN) is an underexploited crop with a rich nutrient content and is used in traditional medicine, but limited information is available on the quantitative characterization of its flavonoids and phenolic acids. We investigated the phenolic profile of whole seeds and cotyledons of five BGN varieties consumed in South Africa using UPLC-qTOF-MS and GC-MS. Twenty-six phenolic compounds were detected/quantified in whole seeds and twenty-four in cotyledon, with six unidentified compounds. Flavonoids include flavan-3-ol (catechin, catechin hexoside-A, catechin hexoside-B), flavonol (quercetin, quercetin-3-O-glucoside, rutin, myricetin, kaempherol), hydroxybenzoic acid (4-Hydroxybenzoic, 2,6 Dimethoxybenzoic, protocatechuic, vanillic, syringic, syringaldehyde, gallic acids), hydroxycinnamic acid (trans-cinnamic, p-coumaric, caffeic, ferulic acids) and lignan (medioresinol). The predominant flavonoids were catechin/derivatives, with the highest content (78.56 mg/g) found in brown BGN. Trans-cinnamic and ferulic acids were dominant phenolic acid. Cotyledons of brown and brown-eyed BGN (317.71 and 378.59 µg/g) had the highest trans-cinnamic acid content, while red seeds had the highest ferulic acid (314.76 µg/g) content. Colored BGN had a significantly (p < 0.05) higher content of these components. Whole BGN contained significantly (p < 0.05) higher amount of flavonoids and phenolic acids, except for the trans-cinnamic acid. The rich flavonoid and phenolic acid content of BGN seeds highlights the fact that it is a good source of dietary phenolics with potential health-promoting properties.

Nano- and Crystal Engineering Approaches in the Development of Therapeutic Agents for Neoplastic Diseases

Cancer is a leading cause of death worldwide. It is a global quandary that requires the administration of many different active pharmaceutical ingredients (APIs) with different characteristics. As is the case with many APIs, cancer treatments exhibit poor aqueous solubility which can lead to low drug absorption, increased doses, and subsequently poor bioavailability and the occurrence of more adverse events. Several strategies have been envisaged to overcome this drawback, specifically for the treatment of neoplastic diseases. These include crystal engineering, in which new crystal structures are formed to improve drug physicochemical properties, and/or nanoengineering in which the reduction in particle size of the pristine crystal results in much improved physicochemical properties. Co-crystals, which are supramolecular complexes that comprise of an API and a co-crystal former (CCF) held together by non-covalent interactions in crystal lattice, have been developed to improve the performance of some anti-cancer drugs. Similarly, nanosizing through the formation of nanocrystals and, in some cases, the use of both crystal and nanoengineering to obtain nano co-crystals (NCC) have been used to increase the solubility as well as overall performance of many anticancer drugs. The formulation process of both micron and sub-micron crystalline formulations for the treatment of cancers makes use of relatively simple techniques and minimal amounts of excipients aside from stabilizers and co-formers. The flexibility of these crystalline formulations with regards to routes of administration and ability to target neoplastic tissue makes them ideal strategies for effectiveness of cancer treatments. In this review, we describe the use of crystalline formulations for the treatment of various neoplastic diseases. In addition, this review attempts to highlight the gaps in the current translation of these potential treatments into authorized medicines for use in clinical practice.

Pathogenic Mechanisms of Secondary Organic Aerosols

Air pollution represents a major health problem and an economic burden. In recent years, advances in air pollution research has allowed particle fractionation and identification of secondary organic aerosol (SOA). SOA is formed from either biogenic or anthropogenic emissions, through a mass transfer from the gaseous mass to the particulate phase in the atmosphere. They can have deleterious impact on health and the mortality of individuals with chronic inflammatory diseases. The pleiotropic effects of SOA could involve different and interconnected pathogenic mechanisms ranging from oxidative stress, inflammation, and immune system dysfunction. The purpose of this review is to present recent findings about SOA pathogenic roles and potential underlying mechanisms focusing on the lungs; the latter being the primary exposed organ to atmospheric pollutants.

New Potential Agents for Malignant Melanoma Treatment-Most Recent Studies 2020-2022

Malignant melanoma (MM) is the most lethal skin cancer. Despite a 4% reduction in mortality over the past few years, an increasing number of new diagnosed cases appear each year. Long-term therapy and the development of resistance to the drugs used drive the search for more and more new agents with anti-melanoma activity. This review focuses on the most recent synthesized anti-melanoma agents from 2020-2022. For selected agents, apart from the analysis of biological activity, the structure-activity relationship (SAR) is also discussed. To the best of our knowledge, the following literature review delivers the latest achievements in the field of new anti-melanoma agents.

Ethacrynic acid and cinnamic acid combination exhibits selective anticancer effects on K562 chronic myeloid leukemia cells

BACKGROUND

Despite the recent advances in chemotherapy, the outcomes and the success of these treatments still remain insufficient. Novel combination treatments and treatment strategies need to be developed in order to achieve more effective treatment. This study was designed to investigate the combined effect of ethacrynic acid and cinnamic acid on cancer cell lines.

METHODS

The anti-proliferative effect of ethacrynic acid and cinnamic acid was investigated by MTT cell viability assay in three different cancer cell lines. Combination indexes were calculated using CompuSyn software. Apoptosis was assessed by flow cytometric Annexin V-FITC/PI double-staining. The effect of the inhibitors on cell cycle distribution was measured by propidium iodide staining.

RESULTS

The combination treatment of ethacrynic acid and cinnamic acid decreased cell proliferation significantly, by 63%, 75% and 70% for K562, HepG2 and TFK-1 cells, respectively. A 5.5-fold increase in the apoptotic cell population was observed after combination treatment of K562 cells. The population of apoptotic cells increased by 9.3 and 0.4% in HepG2 and TFK-1 cells, respectively. Furthermore, cell cycle analysis shows significant cell cycle arrest in S and G2/M phase for K562 cells and non-significant accumulation in G0/G1 phase for TFK-1 and HepG2 cells.

CONCLUSIONS

Although there is a need for further investigation, our results suggest that the inhibitors used in this study cause a decrease in cellular proliferation, induce apoptosis and cause cell cycle arrest.

Advances and challenges in cancer treatment and nutraceutical prevention: the possible role of dietary phenols in BRCA regulation

Over the years, the attention towards the role of phytochemicals in dietary natural products in reducing the risk of developing cancer is rising. Cancer is the second primary cause of mortality worldwide. The current therapeutic options for cancer treatment are surgical excision, immunotherapy, chemotherapy, and radiotherapy. Unfortunately, in case of metastases or chemoresistance, the treatment options become very limited. Despite the advances in medical and pharmaceutical sciences, the impact of available treatments on survival is not satisfactory. Recently, natural products are a great deal of interest as potential anti-cancer agents. Among them, phenolic compounds have gained a great deal of interest, thanks to their anti-cancer activity. The present review focuses on the suppression of cancer by targeting BRCA gene expression using dietary polyphenols, as well as the clinical aspects of polyphenolic agents in cancer therapy. They regulate specific key processes involved in cancer progression and modulate the expression of oncogenic proteins, like p27, p21, and p53, which may lead to apoptosis, cell cycle arrest, inhibition of cell proliferation, and, consequently, cancer suppression. Thus, one of the mechanisms underlying the anti-cancer activity of phenolics involves the regulation of tumor suppressor genes. Among them, the BRCA genes, with the two forms (BRCA-1 and BRCA-2), play a pivotal role in cancer protection and prevention. BRCA germline mutations are associated with an increased risk of developing several types of cancers, including ovarian, breast, and prostate cancers. BRCA genes also play a key role in the sensitivity and response of cancer cells to specific pharmacological treatments. As the importance of BRCA-1 and BRCA-2 in reducing cancer invasiveness, repairing DNA damages, oncosoppression, and cell cycle checkpoint, their regulation by natural molecules has been examined.

Cinnamomi Ramulus inhibits the growth of colon cancer cells via Akt/ERK signaling pathways

Background

Colon cancer (CC) ranks the second highest mortality rate among malignant tumors worldwide, and the current mainstream treatment regimens are not very effective. The unique efficacy of Chinese herb medicine (CHM) for cancer has recently attracted increasing attention. Cinnamomi Ramulus (CR), as a classic CHM, has been widely used in the treatment of a variety of diseases for hundreds of years in China, but its specific pharmacological mechanism against CC needs to be fully evaluated.

Methods

TCMSP and China National Knowledge Infrastructure database were utilized to predict the candidate ingredients of CR, and TCMSP and SwissTargetPrediction database were also employed to predict the drug targets of the candidate ingredients from CR. We subsequently evaluated the therapeutic effect of CR by orally administrating it on CC-bearing mice. Next, we further identified the potential CC-related targets by using Gene Expression Omnibus (GEO) database. Based on these obtained targets, the drug/disease-target PPI networks were constructed using Bisogenet plugin of Cytoscape. The potential core therapeutic targets were then identified through topological analysis using CytoNCA plugin. GO and KEGG enrichment analyses were performed to predict the underlying mechanism of CR against CC. Furthermore, these in silico analysis results were validated by a series of cellular functional and molecular biological assays. UPLC–MS/MS method and molecular docking analysis were employed to identify the potential key components from CR.

Results

In this study, we firstly found that CR has potential therapeutic effect on cancer. Then, oral administration of CR could inhibit the growth of CC cells in C57BL/6 mice, while inhibiting the viability and motility of CC cells in vitro. We obtained 111 putative core therapeutic targets of CR. Subsequent enrichment analysis on these targets showed that CR could induce apoptosis and cell cycle arrest in CC cells by blocking Akt/ERK signaling pathways, which was further experimentally verified. We identified 5 key components from the crude extract of CR, among which taxifolin was found most likely to be the key active component against CC.

Conclusions

Our results show that CR as well as its active component taxifolin holds great potential in treatment of CC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-022-00588-6.

Chemical and Biological Characterization of the Anticancer Potency of Salvia fruticosa in a Model of Human Malignant Melanoma

Malignant melanoma is one of the most aggressive types of skin cancer with an increasing incidence worldwide. Thus, the development of innovative therapeutic approaches is of great importance. Salvia fruticosa (SF) is known for its anticancer properties and in this context, we aimed to investigate its potential anti-melanoma activity in an in vitro model of human malignant melanoma. Cytotoxicity was assessed through a colorimetric-based sulforhodamine-B (SRB) assay in primary malignant melanoma (A375), non-malignant melanoma epidermoid carcinoma (A431) and non-tumorigenic melanocyte neighbouring keratinocyte (HaCaT) cells. Among eight (8) different fractions of S. fruticosa extracts (SF1-SF8) tested, SF3 was found to possess significant cytotoxic activity against A375 cells, while A431 and HaCaT cells remained relatively resistant or exerted no cytotoxicity, respectively. In addition, the total phenolic (Folin-Ciocalteu assay) and total flavonoid content of SF extracts was estimated, whereas the antioxidant capacity was measured via the inhibition of tert-butyl hydroperoxide-induced lipid peroxidation and protein oxidation levels. Finally, apoptotic cell death was assessed by utilizing a commercially available kit for the activation of caspases - 3, - 8 and - 9. In conclusion, the anti-melanoma properties of SF3 involve the induction of both extrinsic and intrinsic apoptotic pathway(s), as evidenced by the increased activity levels of caspases - 8, and - 9, respectively.

Bioguided isolation of a selective compound from Calea phyllolepis leaves against breast cancer cells

Plants of the Calea genus have been reported to contain lipophilic compounds, such as sesquiterpene lactones, with cytotoxic effect against different cancer cell lines. The aim of this manuscript was to investigate the chemical profile and cytotoxic activity of different fractions from Calea phylolepis leaves on different human cancer cell lines. The fractions were prepared using solvent extraction of increasing polarity, yielding hexane, ethyl acetate and methanolic fractions. All fractions were chemically analysed by thin layer chromatography (TLC), and their cytotoxic activity against HT-29 (colon adenocarcinoma), MCF-7 (breast cancer), U-251MG (malignant glioblastoma) and L929 (mouse fibroblast) cell lines was investigated. Among these, the hexane and ethyl acetate fractions showed higher cytotoxic effects, while the methanolic fraction did not show any cytotoxic effects. The major bioactive compound from the hexane fraction (12.15%) was isolated using chromatographic methods and was identified by nuclear magnetic resonance spectroscopy (NMR) and gas chromatography-mass spectrometry (GC-MS) analysis as 6-epi-β-verbesinol coumarate. This compound showed activity against breast cancer cells (IC₅₀  = 5.8 ± 1.0 μg/ml), similar to etoposide. Furthermore, 6-epi-β-verbesinol coumarate showed low cytotoxicity to normal fibroblast cells, suggesting a high selectivity index (SI = 7.39) against breast cancer cells.

Inhibition of α-glucosidase and α-amylase by herbal compounds for the treatment of type 2 diabetes: A validation of in silico reverse docking with in vitro enzyme assays

BACKGROUND

α-Amylase and α-glucosidase are important therapeutic targets for the management of type 2 diabetes mellitus. The inhibition of these enzymes decreases postprandial hyperglycemia. In the present study, compounds found in commercially available herbs and spices were tested for their ability to inhibit α-amylase and α-glucosidase. These compounds were acetyleugenol, apigenin, cinnamic acid, eriodictyol, myrcene, piperine, and rosmarinic acid.

METHODS

The enzyme inhibitory nature of the compounds was evaluated using in silico docking analysis with Maestro software and was further confirmed by in vitro α-amylase and α-glucosidase biochemical assays.

RESULTS

The relationships between the in silico and in vitro results were well correlated; a more negative docking score was associated with a higher in vitro inhibitory activity. There was no significant (P > .05) difference between the inhibition constant (K_i ) value of acarbose, a widely prescribed α-glucosidase and α-amylase inhibitor, and those of apigenin, eriodictyol, and piperine. For α-amylase, there was no significant (P > .05) difference between the K_i value of acarbose and those of apigenin, cinnamic acid, and rosmarinic acid. The effect of the herbal compounds on cell viability was assessed with the sulforhodamine B (SRB) assay in C2C12 and HepG2 cells. Acetyleugenol, cinnamic acid, myrcene, piperine, and rosmarinic acid had similar (P > .05) IC₅₀ values to acarbose.

CONCLUSIONS

Several of the herbal compounds studied could regulate postprandial hyperglycemia. Using herbal plants has several advantages including low cost, natural origin, and easy cultivation. These compounds can easily be consumed as teas or as herbs and spices to flavor food.

Recent Advances in Phenolic Metabolites and Skin Cancer

Skin cancer represents any tumor development from the cutaneous structures within the epidermis, dermis or subcutaneous tissue, and is considered to be the most prevalent type of cancer. Compared to other types of cancer, skin cancer is proven to have a positive growth rate of prevalence and mortality. There are available various treatments, including chemotherapy, immunotherapy, radiotherapy and targeted therapy, but because of the multidrug resistance development, a low success has been registered. By this, the importance of studying naturally occurring compounds that are both safe and effective in the chemoprevention of skin cancer is emphasized. This review focuses on melanoma because it is the deadliest form of skin cancer, with a significantly increasing incidence in the last decades. As chemopreventive agents, we present polyphenols and their antioxidant activity, anti-inflammatory effect, their ability to balance the cell cycle and to induce apoptosis and their various other effects on skin melanoma. Besides chemoprevention, studies suggest that polyphenols can have treating abilities in some conditions. The limitations of using polyphenols are also pointed out, which are related to their poor bioavailability and stability, but as the technology is well developed, it is possible to augment the efficacy of polyphenols in the case of melanoma.

Targeting the Achilles Heel of FtsZ: The Interdomain Cleft

Widespread antimicrobial resistance among bacterial pathogens is a serious threat to public health. Thus, identification of new targets and development of new antibacterial agents are urgently needed. Although cell division is a major driver of bacterial colonization and pathogenesis, its targeting with antibacterial compounds is still in its infancy. FtsZ, a bacterial cytoskeletal homolog of eukaryotic tubulin, plays a highly conserved and foundational role in cell division and has been the primary focus of research on small molecule cell division inhibitors. FtsZ contains two drug-binding pockets: the GTP binding site situated at the interface between polymeric subunits, and the inter-domain cleft (IDC), located between the N-terminal and C-terminal segments of the core globular domain of FtsZ. The majority of anti-FtsZ molecules bind to the IDC. Compounds that bind instead to the GTP binding site are much less useful as potential antimicrobial therapeutics because they are often cytotoxic to mammalian cells, due to the high sequence similarity between the GTP binding sites of FtsZ and tubulin. Fortunately, the IDC has much less sequence and structural similarity with tubulin, making it a better potential target for drugs that are less toxic to humans. Over the last decade, a large number of natural and synthetic IDC inhibitors have been identified. Here we outline the molecular structure of IDC in detail and discuss how it has become a crucial target for broad spectrum and species-specific antibacterial agents. We also outline the drugs that bind to the IDC and their modes of action.

ctc-[Pt(NH3)2(cinnamate)(valproate)Cl2] is a highly potent and low-toxic triple action anticancer prodrug

Pt(iv) prodrugs have gained tremendous attention due to their indisputable advantages compared to cisplatin. Herein, new Pt(iv) derivatives with cinnamic acid at the first axial position, and inhibitor of matrix metalloproteinases-2 and -9, histone deacetylase, cyclooxygenase or pyruvate dehydrogenase at the second axial position are constructed to develop multi-action prodrugs. We demonstrate that Pt(iv) prodrugs are reducible and have superior antiproliferative activity with IC50 values at submicromolar concentrations. Notably, Pt(iv) prodrugs exhibit highly potent anti-tumour activity in an in vivo breast cancer model. Our results support the view that a triple-action Pt(iv) prodrug acts via a synergistic mechanism, which involves the effects of CDDP and the effects of axial moieties, thus jointly leading to the death of tumour cells. These findings provide a practical strategy for the rational design of more effective Pt(iv) prodrugs to efficiently kill tumour cells by enhancing their cellular accumulation and tuning their canonical mechanism.

Exploring the Molecular Mechanism of Cinnamic Acid-Mediated Cytotoxicity in Triple Negative MDA-MB-231 Breast Cancer Cells

BACKGROUND

Cinnamic Acid (CA), also known as 3-phenyl-2-propenoic acid, is a naturally occurring aromatic fatty acid found commonly in cinnamon, grapes, tea, cocoa, spinach and celery. Various studies have identified CA to have anti-proliferative action on glioblastoma, melanoma, prostate and lung carcinoma cells.

OBJECTIVE

Our objective was to investigate the molecular mechanism underlying the cytotoxic effect of CA in killing MDA-MB-231 triple negative breast cancer cells.

METHODS

We performed MTT assay and trypan blue assay to determine cell viability and cell death, respectively. Comet analysis was carried out to investigate DNA damage of individual cells. Furthermore, AO/EtBr assay and sub-G1 analysis using flow cytometry were used to study apoptosis. Protein isolation followed by immunoblotting was used to observe protein abundance in treated and untreated cancer cells.

RESULTS

Using MTT assay, we have determined CA to reduce cell viability in MDA-MB-231 breast cancer cells and tumorigenic HEK 293 cells but not in normal NIH3T3 fibroblast cells. Subsequently, trypan blue assay and comet assay showed CA to cause cell death and DNA damage, respectively, in the MDA-MB-231 cells. Using AO/EtBr staining and sub-G1 analysis, we further established CA to increase apoptosis. Additionally, immunoblotting showed the abundance of TNFA, TNF Receptor 1 (TNFR1) and cleaved caspase-8/-3 proapoptotic proteins to increase with CA treatment. Subsequently, blocking of TNFA-TNFR1 signalling by small molecule inhibitor, R-7050, reduced the expression of cleaved caspase-8 and caspase-3 at the protein level.

CONCLUSION

Thus, from the above observations, we can conclude that CA is an effective anticancer agent that can induce apoptosis in breast cancer cells via TNFA-TNFR1 mediated extrinsic apoptotic pathway.

Network pharmacology-guided mechanism study uncovers inhibitory effect of Mahuang Decoction on lung cancer growth by impeding Akt/ERK signaling pathways

Lung cancer (LC) ranks the leading cause of cancer-related death worldwide, due partially to the unsatisfactory therapeutic effect of the mainstream treatment. Alternatively, Chinese herb medicine (CHM) offers a bright perspective for treating complex diseases. Mahuang Decoction (MHD), a classic CHM formula, has been widely used in treating respiratory diseases in China for centuries, but its action mechanism has yet to be fully investigated. In this study, we first systemically explore the action mechanism of MHD by using network pharmacology and bioinformatic analysis tools, which uncovered a potential "new use of old drug" for MHD in cancer treatment. The therapeutic effect of MHD on LC was then validated by oral administration of MHD in the immunodeficient mice bearing xenografted LC tumors. To better understand the pharmacological activity of MHD against LC, we next constructed a drug/disease-target PPI network composed of 252 putative core therapeutic targets of MHD using Cytoscape. The subsequent enrichment analysis for these targets suggested that MHD could affect the apoptosis and cell cycle of LC cells via impeding Akt/ERK signaling pathways. Notably, these in silico analysis results were further validated by a series of cellular functional and molecular biological assays. Thus, our results show that MHD holds a great potential in LC treatment.

Integrated omics and bioinformatics analyses for the toxic mechanism and material basis of Sophorae Tonkinensis radix et rhizome-induced hepatotoxicity

In traditional Chinese medicine theory, Sophorae Tonkinensis radix et rhizome (ST) has the effects of treating tonsillitis, sore throats, and heat-evil-induced diseases. However, the utilization of ST is relatively restricted owing to its toxicity. The previous studies have made some progress on the mechanism and material basis of ST-induced hepatotoxicity, but there is still no significant breakthrough. In this study, integrated omics and bioinformatics analyses were used to investigate the mechanism and material basis of ST-induced hepatotoxicity. Integrated omics were used to analyze the differentially expressed proteins and metabolites, based on which the significantly dysregulated pathways were analyzed by using MetaboAnalyst. Bioinformatics was applied to screen the toxic targets and material basis. Integrated omics revealed that 254 proteins and 42 metabolites were differentially expressed after the treatment with ST, out of which 7 proteins were significantly enriched in 3 pathways. Bioinformatics showed that 20 compounds may interfere with the expression of 7 toxic targets of ST. Multiple toxic targets of ST-induced hepatotoxicity were found in the study, whose dysregulation may trigger hepatocyte necrosis/apoptosis, liver metastasis, and liver cirrhosis. Multiple compounds may be the toxic material basis in response to these effects.

Healthy Drinks with Lovely Colors: Phenolic Compounds as Constituents of Functional Beverages

Consumers increasingly prefer and seek food and beverages, which, due to their natural characteristics, bring health benefits, both in the prevention of diseases and in their curative power. In this way, the production of nutraceutical foods and beverages gains more and more importance in the market. On the other hand, and because the eyes also eat, producing attractive foods due to their color, texture, appearance, and sensory characteristics is a permanent challenge in the food industry. Being able to gather healthy and attractive items in a single food is an even greater challenge. The long list of benefits associated with phenolic compounds, such as antioxidant, anticancer, anti-inflammatory, and antiaging properties, among others, fully justifies their use in the enrichment of various food products. Thus, in this review, we propose to summarize the potential use of phenolic compounds used as ingredients of pleasant and functional beverages.

Exploring the Potential of Aromatherapy as an Adjuvant Therapy in Cancer and its Complications: A Comprehensive Update

BACKGROUND

Aromatherapy is a traditional practice of employing essential oils for the therapeutic purposes, currently headed under the category of complementary and adjuvant medicine.

OBJECTIVE

The aim of this review article is to summarize the potential health benefits of aromatic essential oil from traditional times till the present. It also proposed some mechanisms which can be utilized as basis for using aromatherapy in cancer and cancer linked complications.

METHODS

To find out the relevant and authentic data, several search engines like Science direct, Pubmed, research gate, etc. were thoroughly checked by inserting key words like aromatherapy, complementary, adjuvant therapy etc. to collect the relevant material in context of article. Also, the chemical components of essential oil were classified based on the presence of functional groups, which are further explored for their cytotoxic potential.

RESULTS

The result depicted the anti-cancer potential of chemical constituents of essential oil against different types of cancer. Moreover, the essential oils show promising anti-inflammatory, anti-microbial, anti-oxidant and anti-mutagenic potential in several studies, which collectively can form the basis for initiation of its anti-cancer utility.

CONCLUSION

Aromatherapy can serve as adjuvant economic therapy in cancer after the standardization of protocol.

An Insight into the Mechanism of Holamine- and Funtumine-Induced Cell Death in Cancer Cells

Holamine and funtumine, steroidal alkaloids with strong and diverse pharmacological activities are commonly found in the Apocynaceae family of Holarrhena. The selective anti-proliferative and cell cycle arrest effects of holamine and funtumine on cancer cells have been previously reported. The present study evaluated the anti-proliferative mechanism of action of these two steroidal alkaloids on cancer cell lines (HT-29, MCF-7 and HeLa) by exploring the mitochondrial depolarization effects, reactive oxygen species (ROS) induction, apoptosis, F-actin perturbation, and inhibition of topoisomerase-I. The apoptosis-inducing effects of the compounds were studied by flow cytometry using the APOPercentage^TM dye and Caspase-3/7 Glo assay kit. The two compounds showed a significantly greater cytotoxicity in cancer cells compared to non-cancer (normal) fibroblasts. The observed antiproliferative effects of the two alkaloids presumably are facilitated through the stimulation of apoptosis. The apoptotic effect was elicited through the modulation of mitochondrial function, elevated ROS production, and caspase-3/7 activation. Both compounds also induced F-actin disorganization and inhibited topoisomerase-I activity. Although holamine and funtumine appear to have translational potential for the development of novel anticancer agents, further mechanistic and molecular studies are recommended to fully understand their anticancer effects.

Monitoring of the Surface Charge Density Changes of Human Glioblastoma Cell Membranes upon Cinnamic and Ferulic Acids Treatment

Cinnamic acid (CA) and ferulic acid (FA) are naturally occurring phenolic acids claimed to exert beneficial effects against disorders related to oxidative stress, including cancer. One such malignancy that still remains a therapeutic challenge mainly due to its heterogeneity and inaccessibility to therapeutic agents is Glioblastoma multiforme (GBM). Here, the influence of CA and FA on the surface charge density of human GBM cell line LN-229 was studied using the electrophoretic light scattering technique. Also, the cytotoxicity of both phenolic acids was determined by metabolic activity-assessing tetrazolium test (MTT) analysis after exposure to CA and FA for 24 h and 48 h. Results showed that both compounds reduced cell viability of LN-229 cells, with more pronounced effect evoked by CA as reflected in IC₅₀ values. Further analyses demonstrated that, after treatment with both phenolic acids, the negative charge of membranes decreased at high pH values and the positive charge of the membranes increased at low pH values compared to the data obtained for untreated cells. Afterward, a four-equilibrium model was applied to estimate the total surface concentrations of both acidic and basic functional groups and their association constants with solution ions in order to calculate theoretical values of membrane surface charge densities. Then, the theoretical data were compared to the experimental data in order to verify the mathematical model. As such, our results indicate that application of electrochemical methods to determine specific drug-membrane interactions might be crucial for predicting their pharmacological activity and bioavailability.

A Multi-action PtIV Conjugate with Oleate and Cinnamate Ligands Targets Human Epithelial Growth Factor Receptor HER2 in Aggressive Breast Cancer Cells

HER2-positive breast cancer is an aggressive subtype that typically responds poorly to standard chemotherapy. To design an anticancer drug selective for HER2-expressing breast cancer, a Pt^IV prodrug with axial oleate and cinnamate ligands was synthesized. We demonstrate its superior antiproliferative activity in monolayer and 3D spheroid models; the antiproliferative efficiency increases gradually with increasing expression of HER2. The results also suggest that the released Pt^II compound inhibits the proliferation of cancer cells by a DNA-damage-mediated mechanism. Simultaneously, the released oleic and cinnamic acid can effectively inhibit HER2 expression. To our knowledge, this is the first platinum-based complex inhibiting HER2 expression that does not contain protein or peptide. Moreover, this Pt^IV prodrug is capable of overcoming the resistance of cancer stem cells (CSCs), inducing death in both CSCs and differentiated cancer cells. Thus, the results substantiate our design strategy and demonstrate the potential of this approach for the development of new, therapeutically relevant compounds.

Biological properties of functional flavoring produced by enzymatic esterification of citronellol and geraniol present in Cymbopogon winterianus essential oil

The chemical composition and biological properties of citronella essential oil were modified by enzymatic esterification reaction of the major monoterpenic alcohols with cinnamic acid. The almost complete conversion of geraniol and citronellol present in the citronella (Cymbopogon winterianus) essential oil, into geranyl (99%) and citronellyl (98%) cinnamates was obtained after 48 hours of reaction using a molar ratio of 3:1 (cinnamic acid/alcohol), lipase concentration (Novozym 435) of 15% (w/w) and 70 °C. The esterified oil showed higher antimicrobial activity against Staphylococcus aureus bacteria resistant to oxacillin and penicillin and also greater larvicidal activity against Aedes aegypti larvae compared to unesterified oil. The results concerning the evaluation of toxicity against Artemia salina and cytotoxicity against monkey kidney epithelial cells also showed the superiority of the esterified oil.

Plant Polyphenolic Compounds Potentiates Therapeutic Efficiency of Anticancer Chemotherapeutic Drugs: A Review

BACKGROUND

Scientific research continues to develop more efficacious drugs to treat and cure cancer, the dreadful disease threatening the human race. Chemotherapy is an essential means in cancer therapy, however, plant drugs having pharmacological safety, can be used alone or as additions to current chemotherapeutic agents to enhance therapeutic efficacy and minimize chemotherapyinduced adverse effects.

OBJECTIVE

A combination therapy where the synergistic effect on multiple targets is possible has gained significance because a one-drug one-target approach fails to yield the desired therapeutic effect. Therefore, a detailed description of important plant polyphenolic compounds with anticancer activity and their role in potentiating chemotherapeutic efficiency of existing anticancer drugs is provided in this review. Systematically screening combinations of active pharmaceutical ingredients for potential synergy with plant compounds may be especially valuable in cancer therapy.

METHODS

We extensively have gone through reviews and research articles available in the literature. We made use of databases such as Google Scholar, Research Gate, PubMed, Science Direct, etc. The following keywords were used in our literature search: "Chemotherapy, drug development, cancer drugs, plant-derived polyphenolics, synergistic studies, combination therapy, diagnosis and genetics."

CONCLUSION

Systematic research studies on screening combinations of plant phytochemicals with potential chemotherapeutic pharmaceuticals shed light on their synergistic effects, mechanisms of actions paving the way to develop more efficient anticancer therapeutics to treat and cure the cancer menace, to nullify chemotherapy-induced adverse effects and our review substantially contributes in this direction.

Curcumin downregulates the PI3K-AKT-mTOR pathway and inhibits growth and progression in head and neck cancer cells

Curcumin, a polyphenol isolated from the rhizome of Curcuma longa, has been studied because of its antioxidant, antimicrobial, and antiinflammatory properties. This study aimed to evaluate the effects of curcumin on head and neck cancer (HNC) cell lines and how it modulates the PI3K-AKT-mTOR signaling pathway. Dose-response curves for curcumin were established for hypopharynx carcinoma (FaDu), tongue carcinoma (SCC-9), and keratinocytes (HaCaT) cell lines and IC₅₀ values were calculated. Cell cycle and cell death were investigated through flow cytometry. Cytoskeleton organization was assessed through phalloidin+FITC staining. qPCR array and western blot were performed to analyze gene and protein expression. Curcumin reduced cell viability in a dose-dependent and selective manner, induced cell death on SCC-9 cells (necrosis/late apoptosis: 44% curcumin vs. 16.4% vehicle), and arrested cell cycle at phase G₂ /M on SCC-9 and FaDu (G₂ : SCC-9-19.1% curcumin vs. 13.4% vehicle; FaDu-37.8% curcumin vs. 12.9% vehicle). Disorganized cytoskeleton and altered cell morphology were observed. Furthermore, curcumin downregulated the PI3K-AKT-mTOR signaling pathway by modifying the expression of key genes and proteins. These findings highlight the promising therapeutic potential of curcumin to inhibit HNC growth and progression and to modulate the PI3K-AKT-mTOR pathway.

p-Methoxycinnamic Acid Diesters Lower Dyslipidemia, Liver Oxidative Stress and Toxicity in High-Fat Diet Fed Mice and Human Peripheral Blood Lymphocytes

The pursuit of cholesterol lowering natural products with less side effects is needed for controlling dyslipidemia and reducing the increasing toll of cardiovascular diseases that are associated with morbidity and mortality worldwide. The present study aimed at the examining effects of p-methoxycinnamic acid diesters (PCO-C) from carnauba (Copernicia prunifera)-derived wax on cytotoxic, genotoxic responses in vitro and on dyslipidemia and liver oxidative stress in vivo, utilizing high-fat diet (HFD) chronically fed Swiss mice. In addition, we evaluated the effect of PCO-C on the expression of key cholesterol metabolism-related genes, as well as the structural interactions between PCO-C and lecithin-cholesterol acyl transferase (LCAT) in silico. Oral treatment with PCO-C was able to reduce total serum cholesterol and low-density lipoprotein (LDL) levels following HFD. In addition, PCO-C reduced excessive weight gain and lipid peroxidation, and increased the gene expression of LCAT following HFD. Furthermore, the high affinity of the studied compound (ΔG: −8.78 Kcal/mol) towards the active sites of mutant LCAT owing to hydrophobic and van der Waals interactions was confirmed using bioinformatics. PCO-C showed no evidence of renal and hepatic toxicity, unlike simvastatin, that elevated aspartate aminotransferase (AST) levels, a marker of liver dysfunction. Finally, PCO-C showed no cytotoxicity or genotoxicity towards human peripheral blood lymphocytes in vitro. Our results suggest that PCO-C exerts hypocholesterolemic effects. The safety of PCO-C in the toxicological tests performed and the reports of its beneficial biological effects render this a promising compound for the development of new cholesterol-lowering therapeutics to control dyslipidemia. More work is needed for further elucidating PCO-C role on lipid metabolism to support future clinical studies.

Platinum (IV) Derivatives with Cinnamate Axial Ligands as Potent Agents Against Both Differentiated and Tumorigenic Cancer Stem Rhabdomyosarcoma Cells

To design an anticancer drug capable of inhibiting not only the proliferation of the differentiated tumor cells but also reducing the tumorigenic capability of cancer stem cells (CSCs), the new Pt^IV prodrugs with axial cinnamate ligands were synthesized. We demonstrate their superior antiproliferative activity in monolayer and 3D spheroid antiproliferative activity tests using panel of cancer cell lines. An outstanding activity was found against rhabdomyosarcoma cells, one of the most problematic and poorly treatable pediatric tumors. The results also suggest that the released Pt^II compound inhibits antiproliferative activity of cancer cells by DNA-damage mediated mechanism; the released cinnamic acid can trigger processes leading to differentiation, making the CSCs more sensitive to killing by the platinum part of the complex. Pt^IV complex with axial cinnamate ligands is the first Pt^IV prodrug capable of overcoming CSCs resistance and induce death in both CSCs and bulk cancer.

Cinnamic Acid Conjugates in the Rescuing and Repurposing of Classical Antimalarial Drugs

Cinnamic acids are compounds of natural origin that can be found in many different parts of a wide panoply of plants, where they play the most diverse biological roles, often in a conjugated form. For a long time, this has been driving Medicinal Chemists towards the investigation of the therapeutic potential of natural, semi-synthetic, or fully synthetic cinnamic acid conjugates. These efforts have been steadily disclosing promising drug leads, but a wide chemical space remains that deserves to be further explored. Amongst different reported approaches, the combination or conjugation of cinnamic acids with known drugs has been addressed in an attempt to produce either synergistic or multi-target action. In this connection, the present review will focus on efforts of the past decade regarding conjugation with cinnamic acids as a tool for the rescuing or the repurposing of classical antimalarial drugs, and also on future perspectives in this particular field of research.

Recent advances of analogues of curcumin for treatment of cancer

Curcumin (CU), an edible natural pigment from Curcuma Longa, has demonstrated extensive anti-tumor effect in vivo and in vitro. With the property of reversing drug resistance and low toxicity, CU has been considered to develop a new adjuvant chemotherapy protocol of cancer. However, the poor stability, solubility, in vivo bioavailability and weak activity of CU greatly limit its clinical application. Therefore, CU analogues have been extensively studied. Starting from the study of natural CU analogues, multiple approaches are being sought to obtain more stable, soluble and effective analogues of CU. This review focuses on the progress of these approaches to more potent CU analogues.

A Subset of New Platinum Antitumor Agents Kills Cells by a Multimodal Mechanism of Action Also Involving Changes in the Organization of the Microtubule Cytoskeleton

The substitution inert platinum agent [Pt(1 S,2 S-diaminocyclohexane)(5,6-dimethyl-1,10-phenanthroline)]²⁺ (56MeSS, 5) is a potent cytotoxic metallodrug. In contrast to conventional cisplatin or oxaliplatin, the mechanism of action (MoA) of 5 is fundamentally different. However, details of the mechanism by which the 5,6-dimethyl-1,10-phenanthroline ligand contributes to the cytotoxicity of 5 and its derivatives have not been sufficiently clarified so far. Here, we show that 5 and its Pt(IV) derivatives exhibit an intriguing potency in the triple-negative breast cancer cells MDA-MB-231. Moreover, we show that the Pt(IV) derivatives of 5 act by multimodal MoA resulting in the global biological effects, that is, they damage nuclear DNA, reduce the mitochondrial membrane potential, induce the epigenetic processes, and last but not least, the data provide evidence that changes in the organization of cytoskeleton networks are functionally important for 5 and its derivatives, in contrast to clinically used platinum cytostatics, to kill cancer cells.