Artemisinin and its derivatives: a promising cancer therapy

Dihydroartemisinin induces ferroptosis in T cell acute lymphoblastic leukemia cells by downregulating SLC7A11 and activating the ATF4‑CHOP signaling pathway

The present study aimed to investigate the anti-leukemic effects of dihydroartemisinin (DHA) on T-cell acute lymphoblastic leukemia (T-ALL) cell lines, Jurkat and Molt-4, and the underlying mechanisms. Cell Counting Kit-8 was performed to measure cell viability. Cell apoptosis and cell cycle distribution were assessed by flow cytometry. The expression levels of ATF4 and CHOP mRNA were assessed by reverse transcription-quantitative PCR, while the protein abundance of SLC7A11, GPX4, ATF4 and CHOP was determined by western blotting. Moreover, malondialdehyde, glutathione (GSH) and reactive oxygen species (ROS) assays were used to detect the levels of ferroptosis. The results showed that DHA suppressed T-ALL cell viability in vitro, and induced cell cycle arrest at S or G2/M phase. DHA also induced ROS burst, activated endoplasmic reticulum (ER) stress, disrupted the system Xc--GSH-GSH peroxidase 4 antioxidant system, and increased lipid peroxide accumulation, resulting in cell death. By contrast, the pharmacological inhibition of ferroptosis alleviated DHA-induced cell death, confirming that DHA induces T-ALL cell death via ferroptosis. Mechanistically, the effect of DHA on ferroptosis was partly mediated by downregulating SLC7A11 and upregulating the ATF4-CHOP signaling pathway, which is associated with ER stress. These results indicated that DHA may induce ferroptosis in T-ALL cell lines and could represent a promising therapeutic agent for treating T-ALL.

Design, Synthesis, and Antitumor Activity of Isoliquiritigenin Amino Acid Ester Derivatives

Isoliquiritigenin (ISL) is a chalcone that has shown great potential in the treatment of cancer. However, its relatively weak activity and low water solubility limit its clinical application. In this study, we designed and synthesized 21 amino acid ester derivatives of ISL and characterized the compounds using 1H NMR and 13C NMR. Among them, compound 9 (IC50 = 14.36 μM) had a better inhibitory effect on human cervical cancer (Hela) than ISL (IC50 = 126.5 μM), and it was superior to the positive drug 5-FU (IC50 = 33.59 μM). The mechanism of the action experiment showed that compound 9 could induce Hela cell apoptosis and autophagy through the PI3K/Akt/mTOR pathway.

Co-delivery of artemisinin and metformin via PEGylated niosomal nanoparticles: potential anti-cancer effect in treatment of lung cancer cells

PURPOSE

Despite the advances in treatment, lung cancer is a global concern and necessitates the development of new treatments. Biguanides like metformin (MET) and artemisinin (ART) have recently been discovered to have anti-cancer properties. As a consequence, in the current study, the anti-cancer effect of MET and ART co-encapsulated in niosomal nanoparticles on lung cancer cells was examined to establish an innovative therapy technique.

METHODS

Niosomal nanoparticles (Nio-NPs) were synthesized by thin-film hydration method, and their physicochemical properties were assessed by FTIR. The morphology of Nio-NPs was evaluated with FE-SEM and AFM. The MTT assay was applied to evaluate the cytotoxic effects of free MET, free ART, their encapsulated form with Nio-NPs, as well as their combination, on A549 cells. Apoptosis assay was utilized to detect the biological processes involved with programmed cell death. The arrest of cell cycle in response to drugs was assessed using a cell cycle assay. Following a 48-h drug treatment, the expression level of hTERT, Cyclin D1, BAX, BCL-2, Caspase 3, and 7 genes were assessed using the qRT-PCR method.

RESULTS

Both MET and ART reduced the survival rate of lung cancer cells in the dose-dependent manner. The IC50 values of pure ART and MET were 195.2 μM and 14.6 mM, respectively while in nano formulated form their IC50 values decreased to 56.7 μM and 78.3 μM, respectively. The combination of MET and ART synergistically decreased the proliferation of lung cancer cells, compared to the single treatments. Importantly, the combination of MET and ART had a higher anti-proliferative impact against A549 lung cancer cells, with lower IC50 values. According to the result of Real-time PCR, hTERT, Cyclin D1, BAX, BCL-2, Caspase 3, and Caspase 7 genes expression were considerably altered in treated with combination of nano formulated MET and ART compared to single therapies.

CONCLUSION

The results of this study showed that the combination of MET and ART encapsulated in Nio-NPs could be useful for the treatment of lung cancer and can increase the efficiency of lung cancer treatment.

Artemisia argyi extracts overcome lapatinib resistance via enhancing TMPRSS2 activation in HER2-positive breast cancer

Breast cancer stands as the predominant malignancy and primary cause of cancer-related mortality among females globally. Approximately 25% of breast cancers exhibit HER2 overexpression, imparting a more aggressive tumor phenotype and correlating with poor prognoses. Patients with metastatic breast cancer receiving HER2 tyrosine kinase inhibitors (HER2 TKIs), such as Lapatinib, develop acquired resistance within a year, posing a critical challenge in managing this disease. Here, we explore the potential of Artemisia argyi, a Chinese herbal medicine known for its anti-cancer properties, in mitigating HER2 TKI resistance in breast cancer. Analysis of the Cancer Genome Atlas (TCGA) revealed diminished expression of transmembrane serine protease 2 (TMPRSS2), a subfamily of membrane proteolytic enzymes, in breast cancer patients, correlating with unfavorable outcomes. Intriguingly, lapatinib-responsive patients exhibited higher TMPRSS2 expression. Our study unveiled that the compounds from Artemisia argyi, eriodictyol, and umbelliferone could inhibit the growth of lapatinib-resistant HER2-positive breast cancer cells. Mechanistically, they suppressed HER2 kinase activation by enhancing TMPRSS2 activity. Our findings propose TMPRSS2 as a critical determinant in lapatinib sensitivity, and Artemisia argyi emerges as a potential agent to overcome lapatinib via activating TMPRSS2 in HER2-positive breast cancer. This study not only unravels the molecular mechanisms driving cell death in HER2-positive breast cancer cells induced by Artemisia argyi but also lays the groundwork for developing novel inhibitors to enhance therapy outcomes.

A Radical-Generating Probe to Release Free Fluorophores and Identify Artemisinin-Sensitive Cancer Cells

The smart light-up probes have been extensively developed to image various enzymes and other bioactive molecules. Upon activation, these probes result in light-up fluorophores that exist in a protein-bound or a free form. The difference between these two forms has not yet been reported. Here, we present a pair of smart light-up probes that generate a protein-bound fluorophore and a free fluorophore upon activation by heme. Probe 8 generated a radical-attached fluorophore that predominantly existed in the free form, while probe 10 generated an α,β-unsaturated ketone-attached fluorophore that showed extensive labeling of proteins. In live-cell imaging, probe 8 showed greater fluorescence intensity than probe 10 when low concentrations (0.1-5 μM) of the probes were used, but probe 8 was less fluorescent than probe 10 when the concentrations of the probes were high (10 μM). Finally, probe 8 was used to reflect the activation level of the endoperoxide bond in cancer cells and to effectively distinguish ART-sensitive cancer cells from ART-insensitive ones.

Induction of ferroptosis by natural products in non-small cell lung cancer: a comprehensive systematic review

Lung cancer is one of the leading causes of cancer-related deaths worldwide that presents a substantial peril to human health. Non-Small Cell Lung Cancer (NSCLC) is a main subtype of lung cancer with heightened metastasis and invasion ability. The predominant treatment approaches currently comprise surgical interventions, chemotherapy regimens, and radiotherapeutic procedures. However, it poses significant clinical challenges due to its tumor heterogeneity and drug resistance, resulting in diminished patient survival rates. Therefore, the development of novel treatment strategies for NSCLC is necessary. Ferroptosis was characterized by iron-dependent lipid peroxidation and the accumulation of lipid reactive oxygen species (ROS), leading to oxidative damage of cells and eventually cell death. An increasing number of studies have found that exploiting the induction of ferroptosis may be a potential therapeutic approach in NSCLC. Recent investigations have underscored the remarkable potential of natural products in the cancer treatment, owing to their potent activity and high safety profiles. Notably, accumulating evidences have shown that targeting ferroptosis through natural compounds as a novel strategy for combating NSCLC holds considerable promise. Nevertheless, the existing literature on comprehensive reviews elucidating the role of natural products inducing the ferroptosis for NSCLC therapy remains relatively sparse. In order to furnish a valuable reference and support for the identification of natural products inducing ferroptosis in anti-NSCLC therapeutics, this article provided a comprehensive review explaining the mechanisms by which natural products selectively target ferroptosis and modulate the pathogenesis of NSCLC.

Artesunate-loaded solid lipid nanoparticles resist esophageal squamous cell carcinoma by inducing Ferroptosis through inhibiting the AKT/mTOR signaling

Esophageal squamous cell carcinoma (ESCC) is a severe malignancy with high incidence and mortality rate in China, while the application of standard chemotherapeutic drugs for ESCC meets the barriers of high toxicity and multiple drug resistance (MDR). In recent years, the anticancer effects of artesunate (ART), a Chinese medicine monomer have gained extensive attentions due to its characteristics of low toxicity, high potency, and reversal of MDR. In this study, we develop the artesunate-loaded solid lipid nanoparticles (SLNART) to overcome the poor water solubility and bioavailability of ART, further improving the efficiency of ART on ESCC treatment. Especially mentioned, SLNART is shown to present marked inhibitory effects on ESCC development based on the induction of ferroptosis by two pathways included upregulating TFR to increase Fe2+ ions and inhibiting the AKT/mTOR signaling to downregulate GPX4. Collectively, this study is the first to pave a promising approach for ESCC therapy based on a strategy of developing SLNART to induce ferroptosis by mediating Fe2+ ions and AKT/mTOR signaling.

AaGL3-like is jasmonate-induced bHLH transcription factor that positively regulates trichome density in Artemisia annua

The leaves of Artemisia annua contain GSTs (Glandular secretory trichomes) that can secrete and store artemisinin, the drug most effective for treating uncomplicated malaria. Therefore, increasing the density of GSTs in A. annua is an efficient way to enhance artemisinin content. However, our understanding of how GSTs develop still needs to be improved. Here, we isolated an A. annua homolog of AtGL3 (GLABRA3), known as AaGL3-like, that positively regulates trichome density in A. annua. AaGL3-like is nuclear-localized and transcriptionally active. It is least expressed in roots and most prominently in aerial components like leaves, stems, and inflorescence. Under JA and GA hormonal treatments, AaGL3-like expression is significantly increased. In transgenic over-expression AaGL3-like lines, trichome developmental genes such as AaHD1 and AaGSW2 showed much increased expression. The AaGL3RNAi line exhibited considerably lower levels of AaHD1 and AaGSW2 transcripts. As a result, the AaGL3-RNAi lines showed reduced levels of artemisinin content and trichome density compared to wild-type and overexpression lines. Additionally, we have found that when co-expressed with AaJAZ8, the induction of trichome developmental genes was reduced as compared to individual OEAaGL3-like lines. Further, AaJAZ8 directly binds to AaGL3-like in the Y2H assay. These findings suggest that AaGL3-like is a jasmonate-induced bHLH transcription factor that drastically increases the final accumulation of artemisinin content by regulating trichome density in A. annua.

Tumor iron homeostasis and immune regulation

Abnormal iron metabolism has long been regarded as a key metabolic hallmark of cancer. As a critical cofactor, iron contributes to tumor progression by participating in various processes such as mitochondrial electron transport, gene regulation, and DNA synthesis or repair. Although the role of iron in tumor cells has been widely studied, recent studies have uncovered the interplay of iron metabolism between tumor cells and immune cells, which may affect both innate and adaptive immune responses. In this review, we discuss the current understanding of the regulatory networks of iron metabolism between cancer cells and immune cells and how they contribute to antitumor immunity, and we analyze potential therapeutics targeting iron metabolism. Also, we highlight several key challenges and describe potential therapeutic approaches for future investigations.

Recent advances in the synthesis and antimalarial activity of 1,2,4-trioxanes

The increasing resistance of various malarial parasite strains to drugs has made the production of a new, rapid-acting, and efficient antimalarial drug more necessary, as the demand for such drugs is growing rapidly. As a major global health concern, various methods have been implemented to address the problem of drug resistance, including the hybrid drug concept, combination therapy, the development of analogues of existing medicines, and the use of drug resistance reversal agents. Artemisinin and its derivatives are currently used against multidrug- resistant P. falciparum species. However, due to its natural origin, its use has been limited by its scarcity in natural resources. As a result, finding a substitute becomes more crucial, and the peroxide group in artemisinin, responsible for the drugs biological action in the form of 1,2,4-trioxane, may hold the key to resolving this issue. The literature suggests that 1,2,4-trioxanes have the potential to become an alternative to current malaria drugs, as highlighted in this review. This is why 1,2,4-trioxanes and their derivatives have been synthesized on a large scale worldwide, as they have shown promising antimalarial activity in vivo and in vitro against Plasmodium species. Consequently, the search for a more convenient, environment friendly, sustainable, efficient, and effective synthetic pathway for the synthesis of 1,2,4-trioxanes continues. The aim of this work is to provide a comprehensive analysis of the synthesis and mechanism of action of 1,2,4-trioxanes. This systematic review highlights the most recent summaries of derivatives of 1,2,4-trioxane compounds and dimers with potential antimalarial activity from January 1988 to 2023.

Design, Synthesis, and Antitumor Activity Evaluation of Artemisinin Bivalent Ligands

Five artemisinin bivalent ligands molecules 4a-4e were designed, synthesized, and confirmed by 1H NMR, 13C NMR, and low-resolution mass spectrometry, and the bioactivities of the target compounds were investigated against four human tumor cell lines in vitro, including BGC-823, HepG-2, MCF-7, and HCT-116. The results showed 4a, 4d, and 4e exhibited significantly tumor cell inhibitory activity compared with the artemisinin and dihydroartemisinin; compound 4e has good biological activity inhibiting BGC-823 with an IC50 value of 8.30 μmol/L. Then, the good correlations with biological results were validated by molecular docking through the established bivalent ligands multi-target model, which showed that 4e could bind well with the antitumor protein MMP-9.

Novel Insights on Ferroptosis Modulation as Potential Strategy for Cancer Treatment: When Nature Kills

Significance: The multifactorial nature of the mechanisms implicated in cancer development still represents a major issue for the success of established antitumor therapies. The discovery of ferroptosis, a novel form of programmed cell death distinct from apoptosis, along with the identification of the molecular pathways activated during its execution, has led to the uncovering of novel molecules characterized by ferroptosis-inducing properties. Recent advances: As of today, the ferroptosis-inducing properties of compounds derived from natural sources have been investigated and interesting findings have been reported both in vitro and in vivo. Critical Issues: Despite the efforts made so far, only a limited number of synthetic compounds have been identified as ferroptosis inducers, and their utilization is still limited to basic research. In this review, we analyzed the most important biochemical pathways involved in ferroptosis execution, with particular attention to the newest literature findings on canonical and non-canonical hallmarks, together with mechanisms of action of natural compounds identified as novel ferroptosis inducers. Compounds have been classified based on their chemical structure, and modulation of ferroptosis-related biochemical pathways has been reported. Future Directions: The outcomes herein collected represent a fascinating starting point from which to take hints for future drug discovery studies aimed at identifying ferroptosis-inducing natural compounds for anticancer therapies. Antioxid. Redox Signal. 40, 40-85.

Prevention and treatment of osteoporosis with natural products: Regulatory mechanism based on cell ferroptosis

CONTEXT

With the development of society, the number of patients with osteoporosis is increasing. The prevention and control of osteoporosis has become a serious and urgent issue. With the continuous progress of biomedical research, ferroptosis has attracted increased attention. However, the pathophysiology and mechanisms of ferroptosis and osteoporosis still need further study. Natural products are widely used in East Asian countries for osteoporosis prevention and treatment.

OBJECTIVE

In this paper, we will discuss the basic mechanisms of ferroptosis, the relationship between ferroptosis and osteoclasts and osteoblasts, and in vitro and in vivo studies of natural products to prevent osteoporosis by interfering with ferroptosis.

METHODS

This article takes ferroptosis, natural products, osteoporosis, osteoblasts and osteoclast as key words. Retrieve literature from 2012 to 2023 indexed in databases such as PubMed Central, PubMed, Web of Science, Scopus and ISI.

RESULTS

Ferroptosis has many regulatory mechanisms, including the system XC -/GSH/GPX4, p62/Keap1/Nrf2, FSP1/NAD (P) H/CoQ10, P53/SAT1/ALOX15 axes etc. Interestingly, we found that natural products, such as Artemisinin, Biochanin A and Quercetin, can play a role in treating osteoporosis by promoting ferroptosis of osteoclast and inhibiting ferroptosis of osteoblasts.

CONCLUSIONS

Natural products have great potential to regulate OBs and OCs by mediating ferroptosis to prevent and treat osteoporosis, and it is worthwhile to explore and discover more natural products that can prevent and treat osteoporosis.

CLEC12A sensitizes differentially responsive breast cancer cells to the anti-cancer effects of artemisinin by repressing autophagy and inflammation

Background

Enhanced inflammatory responses promote tumor progression by activating toll-like receptors (TLRs), which in turn are inhibited by C-type lectin like receptors (CTLRs), like CLEC12A. Although the presence of CLEC12A in acute myeloid leukemia is well established, its role in non-hematopoietic tumors is still obscure. In hematopoietic tumors, CLEC12A mostly inhibits TLRs and modulates inflammatory responses via NF-κB signaling. In this study, the fate of tumor progression was determined by modulating CLEC12A using artemisinin (ART), a FDA-approved anti-malarial drug, known for its anti-cancer and immunomodulatory properties with minimal adverse effects on normal cells.

Method

Effects of ART were primarily determined on hematological factors and primary metastatic organs, such as lungs, kidney and liver in normal and tumor-bearing BALB/c mice. Tumor-bearing mice were treated with different concentrations of ART and expressions of CLEC12A and associated downstream components were determined. CLEC12A was overexpressed in MDA-MB-231 and 4T1 cells, and the effects of ART were analyzed in the overexpressed cells. Silencing TLR4 using vivo morpholino was performed to elucidate its role in tumor progression in response to ART. Finally, CLEC12A modulation by ART was evaluated in the resident cancer stem cell (CSC) population.

Results

ART did not alter physiology of normal mice, in contrast to tumor-bearing mice, where ART led to tumor regression. In addition, ART reduced expression of CLEC12A. Expectedly, TLR4 expression increased, but surprisingly, that of NF-κB (RelA) and JNK/pJNK decreased, along with reduced inflammation, reduced autophagy and increased apoptosis. All the above observations reverted on overexpression of CLEC12A in MDA-MB-231 and 4T1 cells. Inhibition of TLR4, however, indicated no change in the expressions of CLEC12A, NF-κB, or apoptotic markers. The effect of ART showed a similar trend in the CSC population as in cancer cells.

Conclusion

This study, for the first time, confirmed a differential role of CLEC12A in non-hematopoietic tumor and cancer stem cells in response to ART. Subsequent interaction and modulation of CLEC12A with ART induced tumor cell death and abrogation of CSCs, confirming a more comprehensive tumor therapy with reduced risk of recurrence. Therefore, ART may be repurposed as an effective drug for cancer treatment in future.

Artesunate reverses cytarabine resistance in acute myeloid leukemia by blocking the JAK/STAT3 signaling

OBJECTIVES

Although cytarabine (AraC) has greatly contributed to improving the prognosis of patients with acute myeloid leukemia (AML), many patients developed drug resistance and eventually succumbed to AML. Thus, resistance to AraC is a major obstacle to improve the efficacy of chemotherapy in AML. Hence, this study aimed to demonstrate that artesunate (ART) can reliably induce cell death in vitro and block AraC resistance.

METHODS

AML cell lines resistant to AraC were first constructed by repeated dosing for 5 months. Further, we analyzed whether ART intervention affected the sensitivity of AraC-resistant cells to AraC by cell function experiments, mainly including CCK-8 to assess cell viability, flow cytometry to examine apoptosis, and Western blotting to measure the Janus kinase (JAK)/signal transducers and activators of transcription 3 (STAT3) pathway protein expression. Furthermore, whether JAK/STAT3 pathway knockdown has a blocking effect on the efficacy of ART was also assessed.

RESULTS

Co-treatment of ART and AraC increased the sensitivity of AML cells to AraC. Also, it effectively reversed the resistance of AML cells to AraC that is shown by the significantly reduced proliferation and increased apoptosis rates. ART intervention suppressed the activation of the JAK/STAT3 signaling pathway in AraC-resistant AML cells, suggesting that the function of ART in reversing AraC resistance is indeed dependent on the JAK/STAT3 signaling pathway.

CONCLUSIONS

In summary, ART enhanced the sensitivity of AML/AraC-resistant cells to AraC by modulating the JAK/STAT3 pathway.

Molecular and clinical significance of FLT3, NPM1, DNMT3A and TP53 mutations in acute myeloid leukemia patients

BACKGROUND

Acute myeloid leukemia (AML) is a type of blood cancer that affects the bone marrow and blood cells. AML is characterized by the rapid growth and accumulation of abnormal white blood cells, known as myeloblasts, which interfere with the production of normal blood cells.

AIMS

The main aim was to determine the relationship between these genetic alterations and the clinico-haematological parameters and prognostic factors with therapy for Iraqi patients with AML.

METHODS

We used Sanger Sequencing to detect the mutations in 76 AML patients. Clinical data of AML patients were retrospectively analysed to compare the prognosis of each gene mutation group.

RESULTS

Somatic mutations were identified in 47.4% of the enrolled patients in a core set of pathogenic genes, including FLT3 (18 patients, 23.7%), DNMT3A (14, 18.4%), NPM1 (11, 14.5%) and TP53 (5, 6.8%). As multiple mutations frequently coexisted in the same patient, we classified patients into 10 further groups. Two novel mutations were detected in FLT3-ITD, with new accession numbers deposited into NCBI GenBank (OP807465 and OP807466). These two novel mutations were computationally analysed and predicted as disease-causing mutations. We found significant differences between patients with and without the detected mutations in disease progression after induction therapy (remission, failure and death; pv = < 0.001) and statistically significant differences were reported in total leukocyte count (pv = < 0.0001).

CONCLUSION

These genes are among the most frequently mutated genes in AML patients. Understanding the molecular and clinical significance of these mutations is important for guiding treatment decisions and predicting patient outcomes.

Novel Bis-Artemisinin-Phloroglucinol hybrid molecules with dual anticancer and immunomodulatory Activities: Synthesis and evaluation

Bis-(10-deoxydihydroartemisinin)-phloroglucinol (9), has been synthesized in a one-step reaction and has demonstrated strong inhibition to cancer cell proliferation and immunosuppressive activity. The structure modification of the compound reduced its cytotoxicity, and among the analogs, bis-(10-deoxydihydroartemisinin)-phloroglucinol phenyl decanoate (16) showed significant reduction of ear swelling in a mouse model for DNFB-induced delayed-type hypersensitivity without observable toxicity in a dose-dependent manner.

Five Different Artemisia L. Species Ethanol Extracts' Phytochemical Composition and Their Antimicrobial and Nematocide Activity

Among the plants that exhibit significant or established pharmacological activity, the genus Artemisia L. deserves special attention. This genus comprises over 500 species belonging to the largest Asteraceae family. Our study aimed at providing a comprehensive evaluation of the phytochemical composition of the ethanol extracts of five different Artemisia L. species (collected from the southwest of the Russian Federation) and their antimicrobial and nematocide activity as follows: A. annua cv. Novichok., A. dracunculus cv. Smaragd, A. santonica cv. Citral, A. abrotanum cv. Euxin, and A. scoparia cv. Tavrida. The study of the ethanol extracts of the five different Artemisia L. species using the methods of gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-MS/MS) allowed establishing their phytochemical profile. The obtained data on the of five different Artemisia L. species ethanol extracts' phytochemical composition were used to predict the antibacterial and antifungal activity against phytopathogenic microorganisms and nematocidal activity against the free-living soil nematode Caenorhabditis elegans. The major compounds found in the composition of the Artemisia L. ethanol extracts were monoterpenes, sesquiterpenes, flavonoids, flavonoid glycosides, coumarins, and phenolic acids. The antibacterial and antifungal activity of the extracts began to manifest at a concentration of 150 µg/mL. The A. dracunculus cv. Smaragd extract had a selective effect against Gram-positive R. iranicus and B. subtilis bacteria, whereas the A. scoparia cv. Tavrida extract had a selective effect against Gram-negative A. tumefaciens and X. arboricola bacteria and A. solani, R. solani and F. graminearum fungi. The A. annua cv. Novichok, A. dracunculus cv. Smaragd, and A. santonica cv. Citral extracts in the concentration range of 31.3-1000 µg/mL caused the death of nematodes. It was established that A. annua cv. Novichok affects the UNC-63 protein, the molecular target of which is the nicotine receptor of the N-subtype.

Novel ester tethered dihydroartemisinin-3-(oxime/thiosemicarbazide)isatin hybrids as potential anti-breast cancer agents: Synthesis, in vitro cytotoxicity and structure-activity relationship

A series of ester tethered dihydroartemisinin-3-(oxime/thiosemicarbazide)isatin hybrids 7a-p were designed, synthesized, and assessed for their antiproliferative activity against MCF-7, MDA-MB-231, MCF-7/ADR, and MDA-MB-231/ADR breast cancer cell lines. Among them, hybrids 7a,f (IC50 : 1.33-3.84 µM) showed potent activity against triple-negative (MDA-MB-231 and MDA-MB-231/ADR) breast cancer cell lines, and hybrid 7f (IC50 : 3.90 and 10.18 µM) also demonstrated promising activity against estrogen receptor-positive breast cancer cells (MCF-7 and MCF-7/ADR), and the activity was superior to these of artemisinin, dihydroartemisinin, and ADR, revealing their potential to fight against both drug-sensitive and drug-resistant breast cancers. The enriched structure-activity relationships may facilitate further design of more active candidates.

Unveiling the therapeutic potential of natural-based anticancer compounds inducing non-canonical cell death mechanisms

In the Mid-19th century, Rudolf Virchow considered necrosis to be a prominent form of cell death; since then, pathologists have recognized necrosis as both a cause and a consequence of disease. About a century later, the mechanism of apoptosis, another form of cell death, was discovered, and we now know that this process is regulated by several molecular mechanisms that "programme" the cell to die. However, discoveries on cell death mechanisms are not limited to these, and recent studies have allowed the identification of novel cell death pathways that can be molecularly distinguished from necrotic and apoptotic cell death mechanisms. Moreover, the main goal of current cancer therapy is to discover and develop drugs that target apoptosis. However, resistance to chemotherapeutic agents targeting apoptosis is mainly responsible for the failure of clinical therapy and adverse side effects of the chemotherapeutic agents currently in use pose a major threat to the well-being and lives of patients. Therefore, the development of natural-based anticancer drugs with low cellular and organismal side effects is of great interest. In this comprehensive review, we thoroughly examine and discuss natural anticancer compounds that specifically target non-canonical cell death mechanisms.

A comprehensive overview of Artemisinin and its derivatives as anticancer agents

Artemisinin is the crucial ingredient of artemisia annua, a traditional Chinese medicine used for the therapy of malaria in China for hundreds of years. In recent years, the anticancer properties of artemisinin and its derivatives have also been reported. This review has summarized the research and development of artemisinin and its derivatives as anticancer agents, which included both natural and synthetic monomers as well as their dimers. In addition, it highlights the antitumor effects of artemisinin and its derivatives after site-modification or after transformation to a nano-delivery system. Moreover, we have further explored their potential mechanisms of action and also discussed the clinical trials of ARTs used to treat cancer, which will facilitate in further development of novel anticancer drugs based on the scaffold of artemisinin.

Zinc Protoporphyrin-9 Potentiates the Anticancer Activity of Dihydroartemisinin

Besides the clinically proven superior antimalarial activity, artemisinins (ARTs) are also associated with anticancer properties, albeit at much lower potency. Iron and heme have been proposed as possible activators of ARTs against cancer cells. Here we show that zinc protoporphyrin-9 (ZnPPIX), a heme homolog and a natural metabolite for heme synthesis during iron insufficiency, greatly enhanced the anticancer activity of dihydroartemisinin (DHA) in multiple cell lines. Using melanoma B16 and breast cancer 4T1 cells, we demonstrated ZnPPIX dramatically elevated intracellular free heme levels, accompanied by heightened reactive oxidative species (ROS) production. The tumor-suppression activity of ZnPPIX and DHA is mitigated by antioxidant vitamin E or membrane oxidation protectant ferrostatin. In vivo xenograft animal models confirmed that ZnPPIX significantly potentiated the tumor-inhibition capability of DHA while posing no apparent toxicity to the mice. The proliferating index and growth of tumors after the combinatory treatment of DHA and ZnPPIX were evidently reduced. Considering the clinical safety profiles of both DHA and ZnPPIX, their action synergy offers a promising strategy to improve the application of ARTs in our fight against cancer.

Assessment of Thermal and Hydrolytic Stabilities and Aqueous Solubility of Artesunate for Formulation Studies

For the purpose of establishing the optimum processing parameters and storage conditions associated with nanolipid formulations of the artemisinin derivative artesunate, it was necessary to evaluate the thermal stability and solubility profiles of artesunate in aqueous solutions at various temperatures and pH. The effect of increased temperature and humidity on artesunate was determined by storing samples of the raw material in a climate chamber for 3 months and analyzing these by an established HPLC method. Artesunate remained relatively stable during storage up to 40°C ± 0.5°C and 75% relative humidity for 3 months, wherein it undergoes approximately 9% decomposition. At higher temperatures, substantially greater decomposition supervenes, with formation of dihydroartemisinin (DHA) and other products. In solution, artesunate is relatively stable at 15°C with less than 10% degradation over 24 h. The aqueous solubility of artesunate at different pH values after 60 min are pH 1.2 (0.1 M HCl) 0.26 mg/mL, pH 4.5 (acetate buffer) 0.92 mg/mL, distilled water 1.40 mg/mL, and pH 6.8 (phosphate buffer) 6.59 mg/mL, thus relating to the amount of ionized drug present. Overall, for optimal preparation and storage of the designated formulations of artesunate, relatively low temperatures will have to be maintained throughout.

The Effective Treatment of Purpurin on Inflammation and Adjuvant-Induced Arthritis

Rubia cordifolia L. (Rubiaceae), one of the traditional anti-rheumatic herbal medicines in China, has been used to treat rheumatoid arthritis (RA) since ancient times. Purpurin, an active compound of Rubia cordifolia L., has been identified in previous studies and exerts antibacterial, antigenotoxic, anticancer, and antioxidant effects. However, the efficacy and the underlying mechanism of purpurin to alleviate RA are unclear. In this study, the effect of purpurin on inflammation was investigated using macrophage RAW264.7 inflammatory cells, induced by lipopolysaccharide (LPS), and adjuvant-induced arthritis (AIA) rat was established to explore the effect of purpurin on joint damage and immune disorders; the network pharmacology and molecular docking were integrated to dig out the prospective target. Purpurin showed significantly anti-inflammatory effect by reducing the content of IL-6, TNF-α, and IL-1β and increasing IL-10. Besides, purpurin obviously improved joint injury and hypotoxicity in the liver and spleen and regulated the level of FOXP3 and CD4+/CD8+. Furthermore, purpurin reduced the MMP3 content of AIA rats. Network pharmacology and molecular docking also suggested that MMP3 may be the key target of purpurin against RA. The results of this study strongly indicated that purpurin has a potential effect on anti-RA.

Artemisinin suppresses aerobic glycolysis in thyroid cancer cells by downregulating HIF-1a, which is increased by the XIST/miR-93/HIF-1a pathway

The incidence of thyroid cancer (TC) continues to increase worldwide. Aerobic glycolysis, the prominent feature of glucose metabolism in cancer progression, is associated with TC. We first demonstrated that HIF-1a is highly expressed in TC tissues and is positively correlated with the level of XIST in the serum of patients with TC. Then, we proved that XIST regulates the expression of HIF-1a through the XIST/miR-93/HIF-1a pathway, thereby regulating the level of glycolysis in TC cells. Knockdown of XIST inhibits glycolysis, proliferation, the cell cycle and metastasis of TC cells. Finally, we verified that artemisinin could target the degradation of HIF-1a and inhibit glycolysis in TC cells. Collectively, XIST levels in serum may be used as a tumor marker for TC promoted by HIF-1a, which could be treated using artemisinin.

Artemisinin‐isatin hybrids tethered via ethylene linker and their anti‐lung cancer activity

The synthesized 11 artemisinin-isatin hybrids 5a-c and 6a-h tethered via ethylene linker were assessed for their in vitro antiproliferative activity against A549 and H1299 nonsmall-cell lung cancer cell lines as well as their cytotoxicity towards BEAS-2B human normal lung epithelial cells. The preliminary results showed that hybrids 5a-c and 6a-h did not show any cytotoxicity (IC₅₀ : >100 µM) on BEAS-2B cells, and also possessed potential activity (IC₅₀ : 6.99-76.49 µM) against A549 and H1299 lung cancer cell lines. The representative hybrid 6c (IC₅₀ : 6.99 and 7.57 µM) was far more potent than artemisinin (IC₅₀ : >100 µM) and dihydroartemisinin (IC₅₀ : >100 µM), and was slightly less active than doxorubicin (IC₅₀ : 4.14 and 2.77 µM). Moreover, hybrid 6c also exhibited an excellent safety profile and good selectivity with SI values of >13.21. Therefore, hybrid 6c could serve as a promising candidate for further in vivo evaluations.

Identification of Novel Artemisinin Hybrids Induce Apoptosis and Ferroptosis in MCF-7 Cells

A series of novel 1,3,4-oxadiazole-artemisinin hybrids have been designed and synthesized. An MTT assay revealed that most of tested hybrids showed more enhanced anti-proliferative activities than artemisinin, among which A8 had the superior potency with IC₅₀ values ranging from 4.07 μM to 9.71 μM against five tested cancer cell lines. Cell colony formation assays showed that A8 could inhibit significantly more cell proliferation than artemisinin and 5-fluorouracil. Further mechanism studies reveal that A8 induces apoptosis and ferroptosis in MCF-7 cells in a dose-dependent manner, and CYPs inhibition assays reveal that A8 has a moderate inhibitory effect on CYP1A2 and CYP3A4 in the human body at 10 μM. The present work indicates that hybrid A8 may merit further investigation as a potential therapeutic agent.

Artemisinin derivative SM934 in the treatment of autoimmune and inflammatory diseases: therapeutic effects and molecular mechanisms

Artemisinin and its derivatives are the well-known anti-malarial drugs derived from a traditional Chinese medicine. In addition to antimalarial, artemisinin and its derivatives possess distinguished anti-cancer, anti-oxidant, anti-inflammatory and anti-viral activities, but the poor solubility and low bioavailability hinder their clinical application. In the last decades a series of new water-soluble and oil-soluble derivatives were synthesized. Among them, we have found a water-soluble derivative β-aminoarteether maleate (SM934) that exhibits outstanding suppression on lymphocytes proliferation in immunosuppressive capacity and cytotoxicity screening assays with 35-fold higher potency than dihydroartemisinin. SM934 displays significant therapeutic effects on various autoimmune and inflammatory diseases, including systemic lupus erythematosus, antiphospholipid syndrome nephropathy, membranous nephropathy, rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease, and dry eye disease. Here, we summarize the immunomodulatory effects, anti-inflammatory, anti-oxidative and anti-fibrosis activities of SM934 in disease-relevant animal models and present the probable pharmacological mechanisms involved in its therapeutic efficacy. This review also delineates a typical example of natural product-based drug discovery, which might further vitalize natural product exploration and development in pharmacotherapy.

The Anti-Breast Cancer Activity of Dihydroartemisinin-5-methylisatin Hybrids Tethered via Different Carbon Spacers

Sixteen dihydroartemisinin-5-methylisatin hybrids 6a-c and 7a-m tethered via different carbon spacers were assessed for their antiproliferative activity against MCF-7, MDA-MB-231, MCF-7/ADR and MDA-MB-231/ADR breast cancer cell lines as well as cytotoxicity towards MCF-10A cells to investigate the influence of the length of carbon spacers on the activity. The preliminary results illustrated that the length of the carbon spacer was the main parameter which affected the activity, and hybrids tethered via the two-carbon linker showed the highest activity. Amongst the synthesized hybrids, the representative hybrid 7a (IC₅₀: 15.3-20.1 µM) not only demonstrated profound activity against both drug-sensitive and drug-resistant breast cancer cell lines, but also possessed excellent safety and selectivity profile. Collectivity, hybrid 7a was a promising candidate for the treatment of both drug-sensitive and drug-resistant breast cancers and worthy of further preclinical evaluations.

Antimalarial and antitumour activities of the steroidal quinone-methide celastrol and its combinations with artemiside, artemisone and methylene blue

Artemisinin, isolated from the traditional Chinese medicinal plant qīng hāo 青蒿 (Artemisia annua) and its derivatives are used for treatment of malaria. With treatment failures now being recorded for the derivatives and companion drugs used in artemisinin combination therapies new drug combinations are urgently required. The amino-artemisinins artemiside and artemisone display optimal efficacies in vitro against asexual and sexual blood stages of the malaria parasite Plasmodium falciparum and are active against tumour cell lines. In continuing the evolution of combinations of the amino-artemisinins with new drugs, we examine the triterpenoid quinone methide celastrol isolated from the traditional Chinese medicinal plant léi gōng téng 雷公藤 (Tripterygium wilfordii). This compound is redox active, and has attracted considerable attention because of potent biological activities against manifold targets. We report that celastrol displays good IC₅₀ activities ranging from 0.50–0.82 µM against drug-sensitive and resistant asexual blood stage Pf, and 1.16 and 0.28 µM respectively against immature and late stage Pf NF54 gametocytes. The combinations of celastrol with each of artemisone and methylene blue against asexual blood stage Pf are additive. Given that celastrol displays promising antitumour properties, we examined its activities alone and in combinations with amino-artemisinins against human liver HepG2 and other cell lines. IC₅₀ values of the amino-artemisinins and celastrol against HepG2 cancer cells ranged from 0.55–0.94 µM. Whereas the amino-artemisinins displayed notable selectivities (SI > 171) with respect to normal human hepatocytes, in contrast, celastrol displayed no selectivity (SI < 1). The combinations of celastrol with artemiside or artemisone against HepG2 cells are synergistic. Given the promise of celastrol, judiciously designed formulations or structural modifications are recommended for mitigating its toxicity.

Effects of Artemisinin on Escherichia coli–Induced Mastitis in Bovine Mammary Epithelial Cells and Mice

Simple Summary

Bovine mastitis is a persistent and inflammatory reaction of the udder tissue that is usually caused by microbial infection, which can result in substantial losses due to reduced milk yield. Escherichia coli is considered a causative environmental pathogen and has been reported as a common cause of bovine mastitis worldwide. Because of its pathogenicity, Escherichia coli is always an important problem to the dairy industry worldwide and also poses a threat to food safety and public health, and with the widespread use of antibiotics, the resistance of Escherichia coli is increasing. Despite considerable research on bovine mastitis, the disease still remains one of the most prevalent and costly diseases of the dairy industry. The need to control mastitis is driven by multiple considerations, including milk quality, reductions in antimicrobial use, and animal welfare. Artemisinin is an antimalarial drug that was developed from a Chinese traditional herb, Qinghao. In recent years, other effects of artemisinin (including antitumor, anti-inflammatory, antifungal, etc.) have been increasingly discovered and applied. In this study, we demonstrated that artemisinin possesses a protective effect toward Escherichia coli–induced mastitis, thus providing a practical approach for the clinical control of mastitis.

Abstract

Bovine mastitis is an important disease affecting dairy farming, and it causes large economic losses to the dairy industry. Escherichia coli (E. coli) is considered to be a causative environmental pathogen and frequently enters into mammary glands, causing inflammation. Artemisinin is a highly effective malaria remedy and is not easy to develop drug resistance to. In recent years, other effects of artemisinin (including antitumor, anti-inflammatory, antifungal, etc.) have been increasingly discovered and applied. The current study aimed to investigate whether artemisinin could attenuate E. coli–induced inflammation. Through the E. coli mastitis model in MAC-T cells and mice, the protective effects of artemisinin were analyzed by CCK-8 (Cell Counting Kit-8), Western blot, and RT-qPCR. The results showed that artemisinin reversed the decrease of cell viability and upregulated TLR4 (toll-like receptor 4)/NF-κB (nuclear factor κB) and MAPK (mitogen activated protein kinase)/p38 signaling pathways, as well as restrained the expression of TNF-α, IL-6, and IL-1β mRNA caused by E. coli. Meanwhile, artemisinin also alleviated mammary tissue damage, reduced inflammatory cells’ infiltration, and decreased the levels of inflammatory factors in a mice mastitis model. This study demonstrated that artemisinin alleviated the inflammatory response of mouse mastitis and MAC-T cells induced by E. coli, thus providing a practical approach for the clinical control of mastitis.

Antiparasitic Drugs against SARS-CoV-2: A Comprehensive Literature Survey

More than two years have passed since the viral outbreak that led to the novel infectious respiratory disease COVID-19, caused by the SARS-CoV-2 coronavirus. Since then, the urgency for effective treatments resulted in unprecedented efforts to develop new vaccines and to accelerate the drug discovery pipeline, mainly through the repurposing of well-known compounds with broad antiviral effects. In particular, antiparasitic drugs historically used against human infections due to protozoa or helminth parasites have entered the main stage as a miracle cure in the fight against SARS-CoV-2. Despite having demonstrated promising anti-SARS-CoV-2 activities in vitro, conflicting results have made their translation into clinical practice more difficult than expected. Since many studies involving antiparasitic drugs are currently under investigation, the window of opportunity might be not closed yet. Here, we will review the (controversial) journey of these old antiparasitic drugs to combat the human infection caused by the novel coronavirus SARS-CoV-2.

Synthesis of smart carriers based on tryptophan-functionalized magnetic nanoparticles and its application in 5- Fluorouracil delivery

Multifunctional nanocarriers, specifically for tumor targeting and traceable features, have been increasingly considered in cancer therapies. Herein, a novel targeting agent (TA), tryptophan(TRP), was proposed for the synthesis of functionalized APTES-iron oxide nanoparticles using two methods, creating a smart drug delivery system (DDS). In one method, two-step, glutaraldehyde (GA) as a linker, bonded TRP and amino-functionalized magnetite (AMFM), and in the second method, one step, TRP binding was carried out by (3-dimethyl aminopropyl)-N'-ethyl carbodiimide hydrochloride (EDC)/ N-hydroxysuccinimide ester (NHS). The synthesis yield of the second method was 7% higher than the first method. After synthesizing DDS, 5-Fluorouracil (5-FU) was loaded on nanocarriers and was observed that TRP functionalized nanoparticles by GA have better loading efficiency, which was 50% greater than the product from the one-step method. A pH-sensitive release profile was also studied for 5-FU/DDS with the release of almost 75% and 50% at pH 5.5 and 7.4, respectively. To analyze the biological aspects of nanocarriers, human breast cancer, MCF-7, and embryonic kidney, HEK293, cell lines were used for cellular uptake and MTT assays. In-vitro studies confirmed that TRP can act as a TA as its cellular uptake through cancerous cells was 40% greater than normal cells, and the MTT assay confirmed that using DDS can increase and decrease the cell viability of normal cells and cancerous cells, respectively, compared to free drug. Therefore, it was concluded that advanced nano-assembly is a great candidate for breast cancer cell-targeted delivery.

Artemisinin protects against cerebral ischemia and reperfusion injury via inhibiting the NF-κB pathway

This study investigated whether artemisinin (ART) exerts a neuroprotective effect against cerebral ischemia/reperfusion (I/R) injury. Hypoxia-glucose deprivation and reoxygenation (OGD/R) of SH-SY5Y cells were used as the I/R injury model in vitro. Cell viability was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and lactate dehydrogenase (LDH) release was measured. Cell apoptosis and apoptosis-associated protein expression were determined via flow cytometry and western blotting, respectively. The levels of glutathione peroxidase, superoxide dismutase, catalase, and malondialdehyde were determined. The secretion of tumor necrosis factor-α and interleukin-1β was measured using ELISA. The activation of the nuclear factor kappa B (NF-κB) pathway was also determined. The indicated ART concentrations (0, 25, 50, 75, and 100 μM) had no significant effect on SH-SY5Y cell viability and LDH activity. ART promoted cell viability, reduced cell apoptosis, repressed cellular inflammation, and inhibited cellular oxidative stress and NF-κB signaling pathway in OGD/R-induced SH-SY5Y cells. In addition, all the protective effects of ART on OGD/R-induced SH-SY5Y cell injury were significantly reversed by an NF-κB agonist. In conclusion, ART protects neurons from OGD/R-induced damage in vitro by inhibiting the NF-κB signaling pathway. These results suggest that ART may be a potential agent for the treatment of cerebral I/R injury.

Artemisinin Alleviates Intestinal Inflammation and Metabolic Disturbance in Ulcerative Colitis Rats Induced by DSS

Objective

This study is aimed to reveal the possible mechanisms of artemisinin in the treatment of ulcerative colitis (UC) through bioinformatics analysis and experimental verification in UC model rats.

Methods

Firstly, we searched two microarray data of the Gene Expression Omnibus (GEO) database to explore the differentially expressed genes (DEGs) between UC samples and normal samples. Then, we selected DEGs for gene ontology (GO) function enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. The acute UC model of rats was established by using 3.5% dextran sulfate sodium (DSS) for 10 days to verify the core pathway. Finally, we evaluated the therapeutic effect of artemisinin at the molecular level and used metabonomics to study the endogenous metabolites in the rat serum.

Results

We screened in the GEO database and selected two eligible microarray datasets, GSE36807 and GSE9452. We performed GO function and KEGG pathway enrichment analyses of DEGs and found that these DEGs were mainly enriched in the inflammatory response, immune response, and IL-17 and NF-κB signaling pathways. Finally, we verified the IL-17 signaling pathway and key cytokines, and ELISA and immunohistochemical results showed that artemisinin could downregulate the expression of proinflammatory cytokines such as IL-1β and IL-17 in the IL-17 signaling pathway and upregulate the expression of the anti-inflammatory cytokine PPAR-γ. Metabolomics analysis showed that 33 differential metabolites were identified in the artemisinin group (AG) compared to the model group (MG). Differential metabolites were mainly involved in alanine, aspartate, and glutamate metabolism and synthesis and degradation of ketone bodies.

Conclusion

In this study, we found that artemisinin can significantly inhibit the inflammatory response in UC rats and regulate metabolites and related metabolic pathways. This study provides a foundation for further research on the mechanism of artemisinin in the treatment of UC.

Cyclodextrin-Derived ROS-Generating Nanomedicine with pH-Modulated Degradability to Enhance Tumor Ferroptosis Therapy and Chemotherapy

Nowadays, destruction of redox homeostasis to induce cancer cell death is an emerging anti-cancer strategy. Here, the authors utilized pH-sensitive acetalated β-cyclodextrin (Ac-β-CD) to efficiently deliver dihydroartemisinin (DHA) for tumor ferroptosis therapy and chemodynamic therapy in a synergistic manner. The Ac-β-CD-DHA based nanoparticles are coated by an iron-containing polyphenol network. In response to the tumor microenvironment, Fe²⁺ /Fe³⁺ can consume glutathione (GSH) and trigger the Fenton reaction in the presence of hydrogen peroxide (H₂ O₂ ), leading to the generation of lethal reactive oxygen species (ROS). Meanwhile, the OO bridge bonds of DHA are also disintegrated to enable ferroptosis of cancer cells. Their results demonstrate that these nanoparticles acted as a ROS generator to break the redox balance of cancer cells, showing an effective anticancer efficacy, which is different from traditional approaches.

The current scenario on anticancer activity of artemisinin metal complexes, hybrids, and dimers

Cancer, the most significant cause of morbidity and mortality, has already posed a heavy burden on health care systems globally. In recent years, cancer treatment has made a significant breakthrough, but cancer cells inevitably acquire resistance, and the efficacy of the treatment is greatly reduced as the tumor progresses. To overcome the above issues, novel chemotherapeutics are needed urgently. Artemisinin and its derivatives-sesquiterpene lactone compounds possessing a unique peroxy bridge moiety-exhibit excellent safety and tolerability profiles. Mechanistically, artemisinin derivatives can promote cancer cell apoptosis, induce cell cycle arrest and autophagy, and inhibit cancer cell invasion and migration. Accordingly, artemisinin derivatives demonstrate promising anticancer efficacy both in vitro and in vivo, and even in clinical Phase I/II trials. The purpose of the present review article is to provide an emphasis on the current scenario (January 2017-January 2022) of artemisinin derivatives with potential anticancer activity, inclusive of artemisinin metal complexes, hybrids, and dimers. The structure-activity relationships and mechanisms of action are also discussed to facilitate the further rational design of more effective candidates.

Targeting lactate metabolism and glycolytic pathways in the tumor microenvironment by natural products: A promising strategy in combating cancer

Anticancer drugs are not purely effective because of their toxicity, side effects, high cost, inaccessibility, and associated resistance. On the other hand, cancer is a complex public health problem that could intelligently adopt different signaling pathways and alter the body's metabolism to escape from the immune system. One of the cancer strategies to metastasize is modifying pH in the tumor microenvironment, ranging between 6.5 and 6.9. As a powerful determiner, lactate is responsible for this acidosis. It is involved in immune stimulation, including innate and adaptive immunity, apoptotic-related factors (Bax/Bcl-2, caspase), and glycolysis pathways (e.g., GLUT-1, PKM2, PFK, HK2, MCT-1, and LDH). Lactate metabolism, in turn, is interconnected with several dysregulated signaling mediators, including PI3K/Akt/mTOR, AMPK, NF-κB, Nrf2, JAK/STAT, and HIF-1α. Because of lactate's emerging and critical role, targeting lactate production and its transporters is important for preventing and managing tumorigenesis. Hence, exploring and developing novel promising anticancer agents to minimize human cancers is urgent. Based on numerous studies, natural secondary metabolites as multi-target alternative compounds with health-promoting properties possess more high effectiveness and low side effects than conventional agents. Besides, the mechanism of multi-targeted natural sources is related to lactate production and cancer-associated cross-talked factors. This review focuses on targeting the lactate metabolism/transporters, and lactate-associated mediators, including glycolytic pathways. Besides, interconnected mediators to lactate metabolism are also targeted by natural products. Accordingly, plant-derived secondary metabolites are introduced as alternative therapies in combating cancer through modulating lactate metabolism and glycolytic pathways.

Three-Carbon Linked Dihydroartemisinin-Isatin Hybrids: Design, Synthesis and Their Antiproliferative Anticancer Activity

Fifteen dihydroartemisinin-isatin hybrids (5a-e and 6a-j) linked with three-carbon were designed, synthesized. The antiproliferative activity against lung cancer cell lines including drug-sensitive A549, doxorubicin-resistant A549 (A549/DOX) and cisplatin-resistant A549 (A549/DDP) lung cancer cell lines was tested. The cytotocivity towards normal lung epithelial BEAS-2B cell line was also investigated. From the structure-activity relationship (SAR), it was found that hydrogen bond donors (especially hydroxime and thiosemicarbazide) at C-3 position and electron-withdrawing groups (fluoro and chloro) at C-5 position of isatin moiety were beneficial for the activity. A significant part of them (half maximal inhibitory concentration/IC₅₀: 5.72–55.52 μM) demonstrated considerable antiproliferative activity, and the activity was superior to that of dihydroartemisinin (IC₅₀: 69.42–88.03 μM) and artemisinin (IC₅₀: >100 μM). In particular, two hybrids 6a, e (IC₅₀: 5.72–9.84 μM) were not inferior to doxorubicin (IC₅₀: 4.06 μM) and cisplatin (IC₅₀: 9.38 μM) against drug-sensitive A549 cells and were more potent than doxorubicin (IC₅₀: 54.32 and 15.10 μM) and cisplatin (IC₅₀: 19.74 and 66.89 μM) against multidrug-resistant A549/DOX and A549/DDP lung cancer cell lines. In addition, hybrids 6a, e (IC₅₀: >100 μM) showed no toxicity towards BEAS-2B cells, proving their excellent selectivity profile. Furthermore, hybrid 6a also possessed good stability in mouse and human microsomes, as well as excellent pharmacokinetic properties. Accordingly, hybrid 6a could serve as a promising anti-lung cancer chemotherapeutic candidate for further preclinical evaluations.

Emerging Mechanisms and Disease Implications of Ferroptosis: Potential Applications of Natural Products

Ferroptosis, a newly discovered form of regulatory cell death (RCD), has been demonstrated to be distinct from other types of RCD, such as apoptosis, necroptosis, and autophagy. Ferroptosis is characterized by iron-dependent lipid peroxidation and oxidative perturbation, and is inhibited by iron chelators and lipophilic antioxidants. This process is regulated by specific pathways and is implicated in diverse biological contexts, mainly including iron homeostasis, lipid metabolism, and glutathione metabolism. A large body of evidence suggests that ferroptosis is interrelated with various physiological and pathological processes, including tumor progression (neuro)degenerative diseases, and hepatic and renal failure. There is an urgent need for the discovery of novel effective ferroptosis-modulating compounds, even though some experimental reagents and approved clinical drugs have been well documented to have anti- or pro-ferroptotic properties. This review outlines recent advances in molecular mechanisms of the ferroptotic death process and discusses its multiple roles in diverse pathophysiological contexts. Furthermore, we summarize chemical compounds and natural products, that act as inducers or inhibitors of ferroptosis in the prevention and treatment of various diseases. Herein, it is particularly highlighted that natural products show promising prospects in ferroptosis-associated (adjuvant) therapy with unique advantages of having multiple components, multiple biotargets and slight side effects.

Design, Synthesis and Anti-Lung Cancer Evaluation of 1, 2, 3-Triazole Tethered Dihydroartemisinin-Isatin Hybrids

A series of 1,2,3-triazole tethered dihydroartemisinin-isatin hybrids 8a-c and 9a-k were designed and synthesized. Their antiproliferative activity against A549, doxorubicin-resistant A549 (A549/DOX) as well as cisplatin-resistant A549 (A549/DDP) lung cancer cell lines was also investigated in this study. All hybrids (half maximal inhibitory concentration/IC₅₀: 7.54–73.8 μM) were more potent than the parent drug dihydroartemisinin (IC₅₀: 69.4–88.0 μM) and also non-cytotoxic towards mouse embryonic fibroblast cells NIH/3T3 (IC₅₀: >100 μM). The structure-activity relationships illustrated that the substituents on C-3 and C-5 position of isatin moiety influenced the activity significantly. Imine at C-3 position decreased the activity, whereas fluoro at C-5 position enhanced the activity. In particular, hybrids 8a,c (IC₅₀: 7.54–12.1 μM) and 9i (IC₅₀: 9.10–15.9 μM) were comparable to cisplatin (IC₅₀: 7.54–15.9 μM vs 9.38–19.7 μM) against A549 and A549/DOX, but 4.6–7.6 folds more potent than that of cisplatin (IC₅₀: 8.77–14.3 μM vs 66.9 μM) against A549/DDP cells. Moreover, hybrids 8a,c exhibited excellent stability (liver microsomes: 68–83%) in mouse/human microsomes and good pharmacokinetic properties, demonstrating their potential as a novel anti-lung cancer chemotherapeutic candidates.

The Regulatory Effects and the Signaling Pathways of Natural Bioactive Compounds on Ferroptosis

Natural bioactive compounds abundantly presented in foods and medicinal plants have recently received a remarkable attention because of their various biological activities and minimal toxicity. In recent years, many natural compounds appear to offer significant effects in the regulation of ferroptosis. Ferroptosis is the forefront of international scientific research which has been exponential growth since the term was coined. This type of regulated cell death is driven by iron-dependent phospholipid peroxidation. Recent studies have shown that numerous organ injuries and pathophysiological processes of many diseases are driven by ferroptosis, such as cancer, arteriosclerosis, neurodegenerative disease, diabetes, ischemia-reperfusion injury and acute renal failure. It is reported that the initiation and inhibition of ferroptosis plays a pivotal role in lipid peroxidation, organ damage, neurodegeneration and cancer growth and progression. Recently, many natural phytochemicals extracted from edible plants have been demonstrated to be novel ferroptosis regulators and have the potential to treat ferroptosis-related diseases. This review provides an updated overview on the role of natural bioactive compounds and the potential signaling pathways in the regulation of ferroptosis.

Advances in plant-derived natural products for antitumor immunotherapy

In recent years, immunotherapy has emerged as a novel antitumor strategy in addition to traditional surgery, radiotherapy and chemotherapy. It uniquely focuses on immune cells and immunomodulators in the tumor microenvironment and helps eliminate tumors at the root by rebuilding the immune system. Despite remarkable breakthroughs, cancer immunotherapy still faces many challenges: lack of predictable and prognostic biomarkers, adverse side effects, acquired treatment resistance, high costs, etc. Therefore, more efficacious and efficient, safer and cheaper antitumor immunomodulatory drugs have become an urgent requirement. For decades, plant-derived natural products obtained from land and sea have provided the most important source for the development of antitumor drugs. Currently, more attention is being paid to the discovery of potential cancer immunotherapy modulators from plant-derived natural products, such as polysaccharides, phenols, terpenoids, quinones and alkaloids. Some of these agents have outstanding advantages of multitargeting and low side effects and low cost compared to conventional immunotherapeutic agents. We intend to summarize the progress of comprehensive research on these plant-derived natural products and their derivatives and discuss their possible mechanisms in regulating the immune system and their efficacy as monotherapies or in combination with regular chemotherapeutic agents.

Missing-Linker-Assisted Artesunate Delivery by Metal-Organic Frameworks for Synergistic Cancer Treatment

Clinical translation of artesunate (ATS) as a potent antitumor drug has been obstructed by its rapid degradation and low bioavailability. Herein, we report the development of an ATS nanomedicine through the self-assembly with Mn[Co(CN)₆ ]_2/3 □_1/3 metal-organic frameworks (MOFs) that have hidden missing linkers. The defects in MOFs originating from the missing linkers play a key role in increasing the biological stability and tumor accumulation of ATS. Chlorin e6 (Ce6) and ATS can be co-loaded into MOFs for a synergistic antitumor efficacy. In the presence of intracellular HCO₃ ^- , Mn²⁺ acts as an efficient catalyst to promote the bicarbonate-activated H₂ O₂ system which oxidizes ATS to generate reactive oxygen species and induce oxidative death to cancer cells. The released [Co^III (CN)₆ ] linker undergoes a redox reaction with intracellular glutathione to prevent the scavenging ability of reactive oxygen species, contributing to synergistic chemodynamic therapy of ATS and photodynamic therapy of Ce6. Thus, defect-engineered MOFs with hidden missing linkers hold great promise in advancing the practical use of ATS as an antitumor medicine.

Lipid Metabolism Regulates Oxidative Stress and Ferroptosis in RAS-Driven Cancers: A Perspective on Cancer Progression and Therapy

HRAS, NRAS and KRAS, collectively referred to as oncogenic RAS, are the most frequently mutated driver proto-oncogenes in cancer. Oncogenic RAS aberrantly rewires metabolic pathways promoting the generation of intracellular reactive oxygen species (ROS). In particular, lipids have gained increasing attention serving critical biological roles as building blocks for cellular membranes, moieties for post-translational protein modifications, signaling molecules and substrates for ß-oxidation. However, thus far, the understanding of lipid metabolism in cancer has been hampered by the lack of sensitive analytical platforms able to identify and quantify such complex molecules and to assess their metabolic flux in vitro and, even more so, in primary tumors. Similarly, the role of ROS in RAS-driven cancer cells has remained elusive. On the one hand, ROS are beneficial to the development and progression of precancerous lesions, by upregulating survival and growth factor signaling, on the other, they promote accumulation of oxidative by-products that decrease the threshold of cancer cells to undergo ferroptosis. Here, we overview the recent advances in the study of the relation between RAS and lipid metabolism, in the context of different cancer types. In particular, we will focus our attention on how lipids and oxidative stress can either promote or sensitize to ferroptosis RAS driven cancers. Finally, we will explore whether this fine balance could be modulated for therapeutic gain.

Natural Products as a Promising Therapeutic Strategy to Target Cancer Stem Cells

Cancer is still a deadly disease, and its treatment desperately needs to be managed in a very sophisticated way through fast-developing novel strategies. Most of the cancer cases eventually develop into recurrencies, for which cancer stem cells (CSCs) are thought to be responsible. They are considered as a subpopulation of all cancer cells of tumor tissue with aberrant regulation of self-renewal, unbalanced proliferation, and cell death properties. Moreover, CSCs show a serious degree of resistance to chemotherapy or radiotherapy and immune surveillance as well. Therefore, new classes of drugs are rushing into the market each year, which makes the cost of therapy increase dramatically. Natural products are also becoming a new research area as a diverse chemical library to suppress CSCs. Some of the products even show promise in this regard. So, the near future could witness the introduction of natural products as a source of new chemotherapy modalities, which may result in the development of novel anticancer drugs. They could also be a reasonably-priced alternative to highly expensive current treatments. Nowadays, considering the effects of natural compounds on targeting surface markers, signaling pathways, apoptosis, and escape from immunosurveillance have been a highly intriguing area in preclinical and clinical research. In this review, we present scientific advances regarding their potential use in the inhibition of CSCs and the mechanisms by which they kill the CSCs.

Antiviral and Immunomodulation Effects of Artemisia

Background and Objectives: Artemisia is one of the most widely distributed genera of the family Astraceae with more than 500 diverse species growing mainly in the temperate zones of Europe, Asia and North America. The plant is used in Chinese and Ayurvedic systems of medicine for its antiviral, antifungal, antimicrobial, insecticidal, hepatoprotective and neuroprotective properties. Research based studies point to Artemisia's role in addressing an entire gamut of physiological imbalances through a unique combination of pharmacological actions. Terpenoids, flavonoids, coumarins, caffeoylquinic acids, sterols and acetylenes are some of the major phytochemicals of the genus. Notable among the phytochemicals is artemisinin and its derivatives (ARTs) that represent a new class of recommended drugs due to the emergence of bacteria and parasites that are resistant to quinoline drugs. This manuscript aims to systematically review recent studies that have investigated artemisinin and its derivatives not only for their potent antiviral actions but also their utility against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Materials andMethods: PubMed Central, Scopus and Google scholar databases of published articles were collected and abstracts were reviewed for relevance to the subject matter. Conclusions: The unprecedented impact that artemisinin had on public health and drug discovery research led the Nobel Committee to award the Nobel Prize in Physiology or Medicine in 2015 to the discoverers of artemisinin. Thus, it is clear that Artemisia's importance in indigenous medicinal systems and drug discovery systems holds great potential for further investigation into its biological activities, especially its role in viral infection and inflammation.