Dihydroartemisinin selectively inhibits PDGFRα-positive ovarian cancer growth and metastasis through inducing degradation of PDGFRα protein

Exploring combinations of dihydroartemisinin for cancer therapy: A comprehensive review

Cancer remains a significant threat to human health due to its multifaceted causes and complex pathogenesis. While advancements in research have improved outcomes for many cancer patients, treatments for specific tumor types still face limitations. Dihydroartemisinin (DHA), an active metabolite of artemisinin and its derivatives, has proven to be an effective anti-malarial agent. Recently, its anticancer potential has garnered increasing interest as it acts through multiple molecular pathways, including anti-proliferation, induction of apoptosis, autophagy and endoplasmic reticulum (ER) stress, anti-metastasis, inhibition of angiogenesis, and modulation of immune function. This review aims to thoroughly explain and summarize the mechanisms of DHA against cancer and the latest progress in this field. Due to the insufficiency of monotherapy in effectively treating cancer, the use of chemotherapy in combination with alternative therapies has witnessed a notable increase in popularity. DHA has shown synergistic anti-tumor efficacy with a range of therapeutic drugs, but its co-delivery with chemotherapeutics has been limited by low solubility and bioavailability. Nanotechnology-assisted co-delivery of anti-tumor agents, utilizing advanced stimulus-triggered drug release systems in tumor cells, offers the potential to enhance selective delivery and increase antitumor efficacy. Additionally, this article provides suggestions for further research on the anticancer effects of DHA.

PD-L1 antibody-modified plant-derived nanovesicles carrying a STING agonist for the combinational immunotherapy of melanoma

Combination therapies for melanoma face challenges due to asynchronous drug delivery and associated toxicity, underscoring the need for advanced delivery systems. While immune checkpoint inhibitors (ICIs) enhance T cell activity, optimal cytotoxic responses require efficient antigen presentation by mature dendritic cells (DCs), which are often functionally impaired in the tumor microenvironment. Thus, effective treatment requires coordinated T cell activation, DC-mediated priming, and direct tumor suppression. Herein, wild Glycyrrhiza uralensis Fisch roots-derived nanovesicles (GC NV) are demonstrated to be effective inhibitors of melanoma proliferation. The vesicles exert this activity through the intracellular delivery of encapsulated miRNA (miR2916) and bioactive molecules (isoliquiritigenin), with this capacity for intracellular delivery extending to the STING agonist DMXAA. We also demonstrate how chemical modification can be used to install PD-L1 antibodies on the membrane surface of these GC NV, imbuing these vesicles with selectivity for tumor cells. Combining DMXAA encapsulation with surface-displayed PD-L1 antibodies creates vesicles (GP@DMX NV) that both promote DCs maturation and elicit CD8+ T cell response. Our multifunctional GP@DMX NV reverse the immunosuppressive microenvironment of melanoma and significantly enhance the immunotherapeutic potential of immune checkpoints.

Dihydroartemisinin enhances the anti-tumour effect of photodynamic therapy by targeting PKM2-mediated glycolysis in oesophageal cancer cell

Photodynamic therapy (PDT) has been demonstrated to provide immediate relief of oesophageal cancer patients' re-obstruction and extend their lifespan. However, tumour regrowth may occur after PDT due to enhanced aerobic glycolysis. Previous research has confirmed the inhibitory effect of Dihydroartemisinin (DHA) on aerobic glycolysis. Therefore, the current study intends to investigate the function and molecular mechanism of DHA targeting tumour cell aerobic glycolysis in synergia PDT. The combined treatment significantly suppressed glycolysis in vitro and in vivo compared to either monotherapy. Exploration of the mechanism through corresponding experiments revealed that pyruvate kinase M2 (PKM2) was downregulated in treated cells, whereas overexpression of PKM2 nullified the inhibitory effects of DHA and PDT. This study proposes a novel therapeutic strategy for oesophageal cancer through DHA-synergized PDT treatment, targeting inhibit PKM2 to reduce tumour cell proliferation and metastasis.

Huang Lian Jie Du Decoction enhances the anti-tumor efficacy of immune checkpoint inhibitors by activating TLR7/8 signalling in melanoma

BACKGROUND

The clinical application of immune checkpoint inhibitors (ICIs) is limited by their drug resistance, necessitating the development of ICI sensitizers to improve cancer immunotherapy outcomes. Huang Lian Jie Du Decoction (HLJD, Oren-gedoku-to in Japanese, Hwangryunhaedok-tang in Korean), a famous traditional Chinese medicinal prescription, has exhibited potential in the field of cancer treatment. This study aims to investigate the impact of HLJD on the efficacy of ICIs in melanoma and elucidate the underlying mechanisms.

METHODS

The potential synergistic effects of HLJD and ICIs were investigated on the tumor-bearing mice model of B16F10 melanoma, and the tumor infiltration of immune cells was tested by flow cytometry. The differential gene expression in tumors between HLJD and ICIs group and ICIs alone group were analyzed by RNA-seq. The effects of HLJD on oxidative stress, TLR7/8, and type I interferons (IFN-Is) signaling were further validated by immunofluorescence, PCR array, and immunochemistry in tumor tissue.

RESULTS

HLJD enhanced the anti-tumor effect of ICIs, significantly inhibited tumor growth, and prolonged the survival duration in melanoma. HLJD increased the tumor infiltration of anti-tumor immune cells, especially DCs, CD4+ T cells and CD8+T cells. Mechanically, HLJD activated the oxidative stress and TLR7/8 signaling pathway and IFN-Is-related genes in tumors.

CONCLUSIONS

HLJD enhanced the therapeutic benefits of ICIs in melanoma, through increasing reactive oxygen species (ROS), promoting the TLR7/8 pathway, and activating IFN-Is signaling, which in turn activated DCs and T cells.

Research progress on traditional Chinese medicine-induced apoptosis signaling pathways in ovarian cancer cells

ETHNOPHARMACOLOGICAL RELEVANCE

As a "silent killer" that threatens women's lives and health, ovarian cancer (OC) has the clinical characteristics of being difficult to detect, difficult to treat, and high recurrence. Traditional Chinese medicine (TCM) can be utilized as a long-term complementary and alternative therapy since it has shown benefits in alleviating clinical symptoms of OC, decreasing toxic side effects of radiation and chemotherapy, as well as enhancing patients' quality of life.

AIM OF THE REVIEW

This paper reviews how TCM contributes to the apoptosis of OC cells through signaling pathways, including active constituents, extracts, and herbal formulas, with the aim of providing a basis for the development and clinical application of therapeutic strategies for TCM in OC.

METHODS

The search was conducted from scientific databases PubMed, Embase, Web of Science, CNKI, Wanfang, VIP, and SinoMed databases aiming to elucidate the apoptosis signaling pathways in OC cells by TCM. The articles were searched by the keywords "ovarian cancer", "apoptosis", "signaling pathway", "traditional Chinese medicine", "Chinese herbal monomer", "Chinese herbal extract", and "herbal formula". The search was conducted from January 2013 to June 2023. A total of 97 potentially relevant articles were included, including 93 articles on Chinese medicine active constituents or extracts and 4 articles on Chinese herbal compound prescriptions.

RESULTS

TCM can induce apoptosis in OC cells by regulating signaling pathways with obvious advantages, including STAT3, PI3K/AKT, Wnt/β-catenin, MAPK, NF-κB, Nrf2, HIF-1α, Fas/Fas L signaling pathway, etc. CONCLUSION: Chinese medicine can induce apoptosis in OC cells through multiple pathways, targets, and routes. TCM has special advantages for treating OC, providing more reasonable evidence for the research and development of new apoptosis inducers.

Unlocking the power of nanomedicine: the future of nutraceuticals in oncology treatment

Cancer, an intricate and multifaceted disease, is characterized by the uncontrolled proliferation of cells that can lead to serious health complications and ultimately death. Conventional therapeutic strategies mainly target rapidly dividing cancer cells, but often indiscriminately harm healthy cells in the process. As a result, there is a growing interest in exploring novel therapies that are both effective and less toxic to normal cells. Herbs have long been used as natural remedies for various diseases and conditions. Some herbal compounds exhibit potent anti-cancer properties, making them potential candidates for nutraceutical-based treatments. However, despite their promising efficacy, there are considerable limitations in utilizing herbal preparations due to their poor solubility, low bioavailability, rapid metabolism and excretion, as well as potential interference with other medications. Nanotechnology offers a unique platform to overcome these challenges by encapsulating herbal compounds within nanoparticles. This approach not only increases solubility and stability but also enhances the cellular uptake of nutraceuticals, allowing for controlled and targeted delivery of therapeutic agents directly at tumor sites. By harnessing the power of nanotechnology-enabled therapy, this new frontier in cancer treatment presents an opportunity to minimize toxicity while maximizing efficacy. In conclusion, this manuscript provides compelling evidence for integrating nanotechnology with nutraceuticals derived from herbal sources to optimize cancer therapy outcomes. We explore the roadblocks associated with traditional herbal treatments and demonstrate how nanotechnology can help circumvent these issues, paving the way for safer and more effective cancer interventions in future oncological practice.

Repurposing approved non-oncology drugs for cancer therapy: a comprehensive review of mechanisms, efficacy, and clinical prospects

Cancer poses a significant global health challenge, with predictions of increasing prevalence in the coming years due to limited prevention, late diagnosis, and inadequate success with current therapies. In addition, the high cost of new anti-cancer drugs creates barriers in meeting the medical needs of cancer patients, especially in developing countries. The lengthy and costly process of developing novel drugs further hinders drug discovery and clinical implementation. Therefore, there has been a growing interest in repurposing approved drugs for other diseases to address the urgent need for effective cancer treatments. The aim of this comprehensive review is to provide an overview of the potential of approved non-oncology drugs as therapeutic options for cancer treatment. These drugs come from various chemotherapeutic classes, including antimalarials, antibiotics, antivirals, anti-inflammatory drugs, and antifungals, and have demonstrated significant antiproliferative, pro-apoptotic, immunomodulatory, and antimetastatic properties. A systematic review of the literature was conducted to identify relevant studies on the repurposing of approved non-oncology drugs for cancer therapy. Various electronic databases, such as PubMed, Scopus, and Google Scholar, were searched using appropriate keywords. Studies focusing on the therapeutic potential, mechanisms of action, efficacy, and clinical prospects of repurposed drugs in cancer treatment were included in the analysis. The review highlights the promising outcomes of repurposing approved non-oncology drugs for cancer therapy. Drugs belonging to different therapeutic classes have demonstrated notable antitumor effects, including inhibiting cell proliferation, promoting apoptosis, modulating the immune response, and suppressing metastasis. These findings suggest the potential of these repurposed drugs as effective therapeutic approaches in cancer treatment. Repurposing approved non-oncology drugs provides a promising strategy for addressing the urgent need for effective and accessible cancer treatments. The diverse classes of repurposed drugs, with their demonstrated antiproliferative, pro-apoptotic, immunomodulatory, and antimetastatic properties, offer new avenues for cancer therapy. Further research and clinical trials are warranted to explore the full potential of these repurposed drugs and optimize their use in treating various cancer types. Repurposing approved drugs can significantly expedite the process of identifying effective treatments and improve patient outcomes in a cost-effective manner.

SUMOylation of PDGF receptor α affects signaling via PLCγ and STAT3, and cell proliferation

BACKGROUND

The platelet-derived growth factor (PDGF) family of ligands exerts their cellular effects by binding to α- and β-tyrosine kinase receptors (PDGFRα and PDGFRβ, respectively). SUMOylation is an important posttranslational modification (PTM) which regulates protein stability, localization, activation and protein interactions. A mass spectrometry screen has demonstrated SUMOylation of PDGFRα. However, the functional role of SUMOylation of PDGFRα has remained unknown.

RESULTS

In the present study, we validated that PDGFRα is SUMOylated on lysine residue 917 as was previously reported using a mass spectrometry approach. Mutation of lysine residue 917 to arginine (K917R) in PDGFRα substantially decreased SUMOylation, indicating that this amino acid residue is a major SUMOylation site. Whereas no difference in the stability of wild-type and mutant receptor was observed, the K917R mutant PDGFRα was less ubiquitinated than wild-type PDGFRα. The internalization and trafficking of the receptor to early and late endosomes were not affected by the mutation, neither was the localization of the PDGFRα to Golgi. However, the K917R mutant PDGFRα showed delayed activation of PLC-γ and enhanced activation of STAT3. Functional assays showed that the mutation of K917 of PDGFRα decreased cell proliferation in response to PDGF-BB stimulation.

CONCLUSIONS

SUMOylation of PDGFRα decreases ubiquitination of the receptor and affects ligand-induced signaling and cell proliferation.

New insights about the PDGF/PDGFR signaling pathway as a promising target to develop cancer therapeutic strategies

Numerous cancers express platelet-derived growth factors (PDGFs) and PDGF receptors (PDGFRs). By directly stimulating tumour cells in an autocrine manner or by stimulating tumour stromal cells in a paracrine manner, the platelet-derived growth factor (PDGF)/platelet-derived growth factor receptor (PDGFR) pathway is crucial in the growth and spread of several cancers. To combat hypoxia in the tumour microenvironment, it encourages angiogenesis. A growing body of experimental data shows that PDGFs target malignant cells, vascular cells, and stromal cells to modulate tumour growth, metastasis, and the tumour microenvironment. To combat medication resistance and enhance patient outcomes in cancers, targeting the PDGF/PDGFR pathway is a viable therapeutic approach. There have been reports of anomalies in the PDGF pathway, including the gain of function point mutations, activating chromosomal translocations, or overexpression or amplification of PDGF receptors (PDGFRs). As a result, it has been shown that targeting the PDGF/PDGFR signaling pathway is an effective method for treating cancer. As a result, this study will concentrate on the regulation of the PDGF/PDGFR signaling system, in particular the current methods and inhibitors used in cancer treatment, as well as the associated therapeutic advantages and side effects.

Mechanism of epithelial-mesenchymal transition in cancer and its regulation by natural compounds

Epithelial-mesenchymal transition (EMT) is a complex process with a primordial role in cellular transformation whereby an epithelial cell transforms and acquires a mesenchymal phenotype. This transformation plays a pivotal role in tumor progression and self-renewal, and exacerbates resistance to apoptosis and chemotherapy. EMT can be initiated and promoted by deregulated oncogenic signaling pathways, hypoxia, and cells in the tumor microenvironment, resulting in a loss-of-epithelial cell polarity, cell-cell adhesion, and enhanced invasive/migratory properties. Numerous transcriptional regulators, such as Snail, Slug, Twist, and ZEB1/ZEB2 induce EMT through the downregulation of epithelial markers and gain-of-expression of the mesenchymal markers. Additionally, signaling cascades such as Wnt/β-catenin, Notch, Sonic hedgehog, nuclear factor kappa B, receptor tyrosine kinases, PI3K/AKT/mTOR, Hippo, and transforming growth factor-β pathways regulate EMT whereas they are often deregulated in cancers leading to aberrant EMT. Furthermore, noncoding RNAs, tumor-derived exosomes, and epigenetic alterations are also involved in the modulation of EMT. Therefore, the regulation of EMT is a vital strategy to control the aggressive metastatic characteristics of tumor cells. Despite the vast amount of preclinical data on EMT in cancer progression, there is a lack of clinical translation at the therapeutic level. In this review, we have discussed thoroughly the role of the aforementioned transcription factors, noncoding RNAs (microRNAs, long noncoding RNA, circular RNA), signaling pathways, epigenetic modifications, and tumor-derived exosomes in the regulation of EMT in cancers. We have also emphasized the contribution of EMT to drug resistance and possible therapeutic interventions using plant-derived natural products, their semi-synthetic derivatives, and nano-formulations that are described as promising EMT blockers.

New opportunities and challenges of natural products research: When target identification meets single-cell multiomics

Natural products, and especially the active ingredients found in traditional Chinese medicine (TCM), have a thousand-year-long history of clinical use and a strong theoretical basis in TCM. As such, traditional remedies provide shortcuts for the development of original new drugs in China, and increasing numbers of natural products are showing great therapeutic potential in various diseases. This paper reviews the molecular mechanisms of action of natural products from different sources used in the treatment of inflammatory diseases and cancer, introduces the methods and newly emerging technologies used to identify and validate the targets of natural active ingredients, enumerates the expansive list of TCM used to treat inflammatory diseases and cancer, and summarizes the patterns of action of emerging technologies such as single-cell multiomics, network pharmacology, and artificial intelligence in the pharmacological studies of natural products to provide insights for the development of innovative natural product-based drugs. Our hope is that we can make use of advances in target identification and single-cell multiomics to obtain a deeper understanding of actions of mechanisms of natural products that will allow innovation and revitalization of TCM and its swift industrialization and internationalization.

TUG1/MAZ/FTH1 Axis Attenuates the Antiglioma Effect of Dihydroartemisinin by Inhibiting Ferroptosis

Glioma is the most common primary intracranial malignant tumor in the brain. Currently, due to the limited treatment methods, the clinical outcome of patients with standard surgery combined with radiotherapy and chemotherapy is not satisfactory. Therefore, we urgently need to develop effective drugs to solve this problem. As a semisynthetic derivative of artemisinin, dihydroartemisinin (DHA) has been proved to have antitumor activity in glioma, which can induce apoptosis and inhibit the proliferation, migration, and invasion of glioma cells. In recent years, ferroptosis has been identified as another antitumor mechanism of DHA. Researchers have shown that DHA could promote ferroptosis in glioma cells. However, the specific molecular mechanisms of ferroptosis induced by DHA need more exploration. In this study, we found DHA could induce ferroptosis with ROS production and lipid peroxidation in glioma cells. Low expression of GPX4 and high expression of HMOX1 were identified in DHA treated glioma cells. Surprisingly, we found FTH1, a negative regulator of ferroptosis, upregulated in DHA treated glioma cells. It indicated that there should be some mechanisms that may cause ferroptosis attenuation in DHA treated glioma cells. For the first time, we confirmed that MYC-associated zinc finger protein (MAZ) could actively regulate FTH1 by binding to FTH1 promoter by CHIP assay. MAZ was further identified as the direct target of long noncoding RNA (lncRNA) TUG1 through luciferase assay. Downregulated expression of TUG1 and upregulated expression of MAZ were identified in DHA treated glioma cells. TUG1 overexpression or inhibition of FTH1 expression could enhance the antiglioma effect of DHA in vitro and in vivo, providing a promising strategy to enhance the antitumor effect of DHA in glioma.

PDGFR dimer-specific activation, trafficking and downstream signaling dynamics

Signaling through the platelet-derived growth factor receptors (PDGFRs) plays a critical role in multiple cellular processes during development. The two PDGFRs, PDGFRα and PDGFRβ, dimerize to form homodimers and/or heterodimers. Here, we overcome previous limitations in studying PDGFR dimer-specific dynamics by generating cell lines stably expressing C-terminal fusions of each PDGFR with bimolecular fluorescence complementation (BiFC) fragments corresponding to the N-terminal or C-terminal regions of the Venus fluorescent protein. We find that PDGFRβ receptors homodimerize more quickly than PDGFRα receptors in response to PDGF ligand, with increased levels of autophosphorylation. Furthermore, we demonstrate that PDGFRα homodimers are trafficked and degraded more quickly, whereas PDGFRβ homodimers are more likely to be recycled back to the cell membrane. We show that PDGFRβ homodimer activation results in a greater amplitude of phospho-ERK1/2 and phospho-AKT signaling, as well as increased proliferation and migration. Finally, we demonstrate that inhibition of clathrin-mediated endocytosis leads to changes in cellular trafficking and downstream signaling, particularly for PDGFRα homodimers. Collectively, our findings provide significant insight into how biological specificity is introduced to generate unique responses downstream of PDGFR engagement. This article has an associated First Person interview with the first author of the paper.

LC-MS/TOF Characterization and Stability Study of Artesunate in Different Solvent Systems

Artemisinin (ART) is a sesquiterpene lactone and a popular malaria drug used in many parts of the world. Artesunate (ARTS) is a semi-synthetic derivative of ART with improved pharmacokinetic properties. However, the half-life of ARTS is less than an hour in vivo. The analysis of this drug in vitro in different solvent systems using LC-MS/TOF showed a solvent-driven breakdown. ARTS breakdown formed several derivatives, including dihydroartemisinin (DHA), artemether (ARTM) and DHA-dimer among others, at different rates in different solvent composition systems. The change in temperature from room temperature to physiological temperature (37 °C) was found to enhance the rate of the ARTS breakdown. In methanol, ARTS mainly formed ARTM with a chromatographic peak decrease of about 3.13%, while methanol and water (90:10) v/v mainly gave rise to DHA and ARTM with about an 80% chromatographic peak decrease. On the other hand, ARTS in methanol and ammonium acetate (85:15) v/v formed DHA, ARTM, DHA-dimer and other reaction peaks with about a 97% peak decrease and the formation of an orange solution pointing to a molecular re-arrangement reaction. These results have an important bearing on research on the analysis of artemisinin drugs conducted on these common solvents.

Ejiao ameliorates lipopolysaccharide-induced pulmonary inflammation via inhibition of NFκB regulating NLRP3 inflammasome and mitochondrial ROS

There is no effective treatment for acute lung injury (ALI) at present. Some studies have reported the anti-inflammatory effect of Ejiao, but no study has addressed the underlying action mechanism. In this study, the CCK8 assay displayed Ejiao had a protective effect against LPS-elicited inflammatory lung epithelial Beas 2B cells (LILEB 2B cells). Beas 2B cells treated with LPS and Ejiao were challenged with NFκB inhibitor Bay11-7082 and ROS scavenger N-acetyl cysteine (NAC) alone and in combination. The results of qRT-PCR, Western blotting and fluorescence labeling experiments using Bay11-7082 and NAC demonstrated Ejiao could significantly decrease the expression of p-p65 and p-IκBα in NFκB signaling pathway and its downstream NLRP3, ASC, Caspase-1 and IL-1β related to pyroptosis of LILEB 2B cells. Moreover, Ejiao reduced the production of mitochondrial ROS and reversed the change of mitochondrial membrane potential of LILEB 2B cells. Then, HE staining demonstrated Ejiao had a protective effect against the LPS-elicited ALI mouse model (LAMM). Ejiao also dramatically decreased the cell amount and the overall protein concentration of bronchoalveolar lavage fluid in LAMM. Immunohistochemical staining showed Ejiao remarkably reduced the expression of p-p65 and p-IκBα in NFκB signaling pathway and its downstream NLRP3, ASC, Caspase-1 and IL-1β. The ELISA of IL-1β revealed Ejiao could dose-dependably decrease the concentration of IL-1β in lung tissues, serum and BALF of LAMM. Finally, fluorescence labeling demonstrated Ejiao significantly reduced the mitochondrial ROS generation in the lung tissue of LAMM. This finding may afford a novel strategy for the precaution and therapy of ALI.

Amygdalin Induced Mitochondria-Mediated Apoptosis of Lung Cancer Cells via Regulating NF[Formula: see text]B-1/NF[Formula: see text]B Signaling Cascade in Vitro and in Vivo

Lung cancer is the most commonly diagnosed cancer and the leading cause of cancer death worldwide. Amygdalin, a natural compound commonly distributed in plants of the Rosaceae species, owns anticancer activity, less side effects, wide source, and relatively low price. Although the apoptosis is a central process activated by amygdalin in cancer cells, the underlying molecular mechanisms through which amygdalin induces the apoptosis of lung cancer cells remain poorly understood. In this research work, amygdalin could suppress the proliferation of lung cancer A549 and PC9 cells by CCK8 assay. Amygdalin significantly promoted the apoptosis of lung cancer A549 and PC9 cells stained with Annexin V-FITC/PI by flow cytometry assay. Furthermore, amygdalin dose-dependently decreased the mitochondrial membrane potential (MMP) with JC-1 dye by flow cytometry. To investigate the underlying molecular mechanisms through which amygdalin induced mitochondria-mediated apoptosis of cancer cells, the differentially-expressed genes with a fold change >2.0 and [Formula: see text] < 0.05 were acquired from the cDNA microarray analysis. The results of qRT-PCR further confirmed that the differentially-expressed level of the NF[Formula: see text]B-1 gene was most obviously enhanced in lung cancer cells treated with amygdalin. The results of immunofluorescence staining, Western blotting and siRNA knockdown indicated that amygdalin induced mitochondria-mediated apoptosis of lung cancer cells via enhancing the expression of NF[Formula: see text]B-1 and inactivating NF[Formula: see text]B signaling cascade and further changing the expressions of proteins (Bax, Bcl-2, cytochrome C, caspase 9, caspase 3 and PARP) related to apoptosis, which were further checked by in vivo study of the lung cancer cell xenograft mice model accompanying with immunohistochemical staining and TUNEL staining. Our results indicated that amygdalin might be a potential activator of NF[Formula: see text]B-1, which sheds more light on the molecular mechanism of anticancer effects of amygdalin. These results highlighted amygdalin as a potential therapeutic anticancer agent, which warrants its development as a therapy for lung cancer.

Artemisinins in Combating Viral Infections Like SARS-CoV-2, Inflammation and Cancers and Options to Meet Increased Global Demand

Artemisinin is a natural bioactive sesquiterpene lactone containing an unusual endoperoxide 1, 2, 4-trioxane ring. It is derived from the herbal medicinal plant Artemisia annua and is best known for its use in treatment of malaria. However, recent studies also indicate the potential for artemisinin and related compounds, commonly referred to as artemisinins, in combating viral infections, inflammation and certain cancers. Moreover, the different potential modes of action of artemisinins make these compounds also potentially relevant to the challenges the world faces in the COVID-19 pandemic. Initial studies indicate positive effects of artemisinin or Artemisia spp. extracts to combat SARS-CoV-2 infection or COVID-19 related symptoms and WHO-supervised clinical studies on the potential of artemisinins to combat COVID-19 are now in progress. However, implementing multiple potential new uses of artemisinins will require effective solutions to boost production, either by enhancing synthesis in A. annua itself or through biotechnological engineering in alternative biosynthesis platforms. Because of this renewed interest in artemisinin and its derivatives, here we review its modes of action, its potential application in different diseases including COVID-19, its biosynthesis and future options to boost production.

Artemisinin Inhibits the Migration and Invasion in Uveal Melanoma via Inhibition of the PI3K/AKT/mTOR Signaling Pathway

Uveal melanoma is the most common primary ocular neoplasm in adults, with many patients ending up developing liver metastasis and facing a significant reduction of their life expectancy due to the lack of efficient treatments. Artemisinin is an antimalarial drug that has been widely used in the clinic and whose anticancer properties have also been described. Its reported safety, affordability, and ability to reach the ocular tissues point that it has a potential therapeutic agent against uveal melanoma. In the present study, we found that a subantimalaria dosage of artemisinin significantly attenuated the migration and invasion potential of uveal melanoma cells, in a concentration-dependent manner. Assessment of the mechanisms underlying artemisinin anticancer action revealed that its use dramatically reduced the phosphorylation of PI3K, AKT, and mTOR in UM cells. Further inhibition of PI3K signaling, using LY294002, or of mTOR, by rapamycin, blocked the migration and invasion of UM cells similarly to artemisinin. In contrast, AKT or mTOR activator (Sc79 and MHY1485, respectively) attenuated the inhibitory effect of artemisinin on the migration and invasion abilities of UM cells, further validating that artemisinin's anticancer effect is likely to be mediated via inhibition of the PI3K/AKT/mTOR pathway. Artemisinin also induced mitochondrial membrane potential loss and apoptosis of UM cells, having no significant toxic effect on normal retinal neuronal cells RGC-5 and epithelial cells D407. These findings and the reported safety of artemisinin's clinical dosage strongly suggest the therapeutic potential of artemisinin in the prevention and treatment of uveal melanomas.

Dihydroartemisinin Suppresses the Tumorigenesis and Cycle Progression of Colorectal Cancer by Targeting CDK1/CCNB1/PLK1 Signaling

Dihydroartemisinin (DHA), a well-known antimalarial drug, has been widely investigated for its antitumor effects in multiple malignancies. However, its effects and regulatory mechanisms in colorectal cancer (CRC) are still unproved. In this study, in vitro experiments including CCK8, EdU, Transwell, and flow cytometry analyses and an in vivo tumorigenesis model were conducted to assess the effects of DHA on the bio-behaviors of CRC cells. Additionally, RNA-seq combined with gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses was used to obtain the targets of DHA, and these were verified by molecular docking, qRT-PCR, and Western blotting. As a result, we found that DHA significantly suppressed the proliferation, DNA synthesis, and invasive capabilities and induced cell apoptosis and cell cycle arrest in HCT116, DLD1, and RKO cells in vitro and in vivo. Further analyses indicated that the targets of DHA were predominantly enriched in cell cycle-associated pathways, including CDK1, CCNB1, and PLK1; and DHA could bind with the CDK1/CCNB1 complex and inhibit the activation of CDK1/CCNB1/PLK1 signaling. Moreover, cucurbitacin E, a specific inhibitor of the CDK1/CCNB1 axis, enhanced the inhibitory effects of DHA on DNA synthesis and colony formation in HCT116 and DLD1 cells. In short, DHA could suppress the tumorigenesis and cycle progression of CRC cells by targeting CDK1/CCNB1/PLK1 signaling.

Dihydroartemisinin: A Potential Drug for the Treatment of Malignancies and Inflammatory Diseases

Dihydroartemisinin (DHA) has been globally recognized for its efficacy and safety in the clinical treatment of malaria for decades. Recently, it has been found that DHA inhibits malignant tumor growth and regulates immune system function in addition to anti-malaria. In parasites and tumors, DHA causes severe oxidative stress by inducing excessive reactive oxygen species production. DHA also kills tumor cells by inducing programmed cell death, blocking cell cycle and enhancing anti-tumor immunity. In addition, DHA inhibits inflammation by reducing the inflammatory cells infiltration and suppressing the production of pro-inflammatory cytokines. Further, genomics, proteomics, metabolomics and network pharmacology of DHA therapy provide the basis for elucidating the pharmacological effects of DHA. This review provides a summary of the recent research progress of DHA in anti-tumor, inhibition of inflammatory diseases and the relevant pharmacological mechanisms. With further research of DHA, it is likely that DHA will become an alternative therapy in the clinical treatment of malignant tumors and inflammatory diseases.

The role of PDGFRA as a therapeutic target in young colorectal cancer patients

Background

Young patients with colorectal cancer (CRC) exhibit poor prognoses compared to older patients due to the difficulty in early diagnosis and treatment. However, the underlying molecular characteristics are still unclear.

Methods

We conducted a comprehensive analysis of 49 CRC patients without hereditary CRC using the whole-exome and RNA sequencing with tumor and matched normal samples. A total of 594 TCGA samples and 4 patient-derived cells were utilized for validation.

Results

Consensus molecular subtype 4 (CMS4) (53.85%) and CMS2 (38.46%) were enriched in the young (≤ 40 years) and old (> 60 years) age groups, respectively. A CMS4-associated gene, platelet-derived growth factor receptor α (PDGFRA), was significantly upregulated in young patients with CRC (FC = 3.21, p = 0.0001) and was negatively correlated with age (p = 0.0001, R = − 0.526). Moreover, PDGFRA showed a positive co-expression with metastasis-related genes in young CRC patients. In vitro validation confirmed that young patient-derived cells (PDCs) showed an enriched expression of PDGFRA compared to old PDCs and a reduced proliferation rate by knockdown of PDGFRA. Furthermore, young CRC patients were more sensitive to regorafenib, a PDGFRA-targeting drug, than old CRC patients.

Conclusions

Our study suggests that CRC in young patients is associated with CMS4 and PDGFRA. In addition, PDGFRA may serve potential of novel therapeutic strategies and represent a predictive biomarker of response to regorafenib for young CRC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-03088-7.

Inhibitory Effect of Dihydroartemisinin on the Proliferation and Migration of Melanoma Cells and Experimental Lung Metastasis From Melanoma in Mice

Melanoma is aggressive and can metastasize in the early stage of tumor. It has been proved that dihydroartemisinin (DHA) positively affects the treatment of tumors and has no apparent toxic and side effects. Our previous research has shown that DHA can suppress the formation of melanoma. However, it remains poorly established how DHA impacts the invasion and metastasis of melanoma. In this study, B16F10 and A375 cell lines and metastatic tumor models will be used to investigate the effects of DHA. The present results demonstrated that DHA inhibited the proliferative capacity in A375 and B16F10 cells. As expected, the migration capacity of A375 and B16F10 cells was also reduced after DHA administration. DHA alleviated the severity and histopathological changes of melanoma in mice. DHA induced expansion of CD8⁺CTL in the tumor microenvironment. By contrast, DHA inhibited Treg cells infiltration into the tumor microenvironment. DHA enhanced apoptosis of melanoma by regulating FasL expression and Granzyme B secretion in CD8⁺CTLs. Moreover, DHA impacts STAT3-induced EMT and MMP_S in tumor tissue. Furthermore, Metabolomics analysis indicated that PGD2 and EPA significantly increased after DHA administration. In conclusion, DHA inhibited the proliferation, migration and metastasis of melanoma in vitro and in vivo. These results have important implications for the potential use of DHA in the treatment of melanoma in humans.

Recent pharmacological advances in the repurposing of artemisinin drugs

Artemisinins are a family of sesquiterpene lactones originally derived from the sweet wormwood (Artemisia annua). Beyond their well-characterized role as frontline antimalarial drugs, artemisinins have also received increased attention for other potential pharmaceutical effects, which include antiviral, antiparsitic, antifungal, anti-inflammatory, and anticancer activities. With concerted efforts in further preclinical and clinical studies, artemisinin-based drugs have the potential to be viable treatments for a great variety of human diseases. Here, we provide a comprehensive update on recent reports of pharmacological actions and applications of artemisinins outside of their better-known antimalarial role and highlight their potential therapeutic viability for various diseases.

Drug Repurposing in Oncology: Current Evidence and Future Direction

BACKGROUND

Drug repurposing, the application of known drugs and compounds with a primary non-oncology purpose, might be an attractive strategy to offer more effective treatment options to cancer patients at a low cost and reduced time.

METHODS

This review described a total of 10 kinds of non-oncological drugs from more than 100 mechanical studies as well as evidence from population-based studies. The future direction of repurposed drug screening is discussed by using patient-derived tumor organoids.

RESULTS

Many old drugs showed previously unknown effects or off-target effects and can be intelligently applied for cancer chemoprevention and therapy. The identification of repurposed drugs needs to combine evidence from mechanical studies and population-based studies. Due to the heterogeneity of cancer, patient-derived tumor organoids can be used to screen the non-oncological drugs in vitro.

CONCLUSION

These identified old drugs could be repurposed in oncology and might be added as adjuvants and finally benefit patients with cancers.

Dihydroartemisinin regulates apoptosis, migration, and invasion of ovarian cancer cells via mediating RECK

BACKGROUND

Dihydroartemisinin (DHA) possesses an inhibitory effect on ovarian cancer and promotes reversion-inducing cysteine-rich protein with Kazal motifs (RECK) expression in glioma cells. This study explored the role of DHA and RECK on ovarian cancer.

METHODS

The RECK level in ovarian cancer was analyzed under GEPIA 2 database and proved by RT-qPCR. After being treated with DHA or infected with siRECK lentivirus, the viability, apoptosis, migration, and invasion of ovarian cancer cells were evaluated by CCK-8, flow cytometry, wound healing, and transwell assays. Also, the expressions of factors related to apoptosis and epithelial-mesenchymal transition were measured by Western blot or RT-qPCR.

RESULTS

DHA-treatment weakened the viability, migration, invasion, and enhanced apoptosis of ovarian cancer cells. DHA also down-regulated the levels of Bcl-2, N-cadherin, and Vimentin, and up-regulated the levels of Bax, C-caspase-3 and E-cadherin in ovarian cancer cells. RECK was lowly expressed in both ovarian cancer tissues and cells. siRECK not only had an effect opposite to DHA on the viability, apoptosis, migration, invasion, and related-factors of ovarian cancer cells but also offset the effect of DHA on ovarian cancer cells.

CONCLUSION

DHA regulated apoptosis, migration, and invasion of ovarian cancer cells via mediating RECK.

The emerging complexity of PDGFRs: activation, internalization and signal attenuation

The platelet-derived growth factor receptor (PDGFR) family of receptor tyrosine kinases allows cells to communicate with the environment to regulate diverse cellular activities. Here, we highlight recent data investigating the structural makeup of individual PDGFRs upon activation, revealing the importance of the whole receptor in the propagation of extracellular ligand binding and dimerization. Furthermore, we review ongoing research demonstrating the significance of receptor internalization and signal attenuation in the regulation of PDGFR activity. Interactions with internalization machinery, signaling from endosomes, receptor degradation and receptor recycling are physiological means by which cells fine-tune PDGFR responses to growth factor stimulation. In this review, we discuss the biophysical, structural, in silico and biochemical data that have provided evidence for these mechanisms. We further highlight the commonalities and differences between PDGFRα and PDGFRβ signaling, revealing critical gaps in knowledge. In total, this review provides a conclusive summary on the state of the PDGFR field and underscores the need for novel techniques to fully elucidate the mechanisms of PDGFR activation, internalization and signal attenuation.

Therapeutic Potentials and Mechanisms of Artemisinin and its Derivatives for Tumorigenesis and Metastasis

BACKGROUND

Tumor recurrence and metastasis are still leading causes of cancer mortality worldwide. The influence of traditional treatment strategies against metastatic tumors may still be limited. To search for novel and powerful agents against tumors has become a major research focus. In this study, Artemisinin (ARM), a natural compound isolated from herbs, Artemisia annua L., proceeding from drug repurposing methods, attracts more attention due to its good efficacy and tolerance in antimalarial practices, as well as newly confirmed anticancer activity.

METHODS

We have searched and reviewed the literatures about ARM and its derivatives (ARMs) for cancer using keywords "artemisinin" until May 2019.

RESULTS

In preclinical studies, ARMs can induce cell cycle arrest and cell death by apoptosis etc., to inhibit the progression of tumors, and suppress EMT and angiogenesis to inhibit the metastasis of tumors. Notably, the complex relationships of ARMs and autophagy are worth exploring. Inspired by the limitations of its antimalarial applications and the mechanical studies of artemisinin and cancer, people are also committed to develop safer and more potent ARM-based modified compounds (ARMs) or combination therapy, such as artemisinin dimers/ trimers, artemisinin-derived hybrids. Some clinical trials support artemisinins as promising candidates for cancer therapy.

CONCLUSION

ARMs show potent therapeutic potentials against carcinoma including metastatic tumors. Novel compounds derived from artemisinin and relevant combination therapies are supposed to be promising treatment strategies for tumors, as the important future research directions.

Dihydroartemisinin inhibits the tumorigenesis and invasion of gastric cancer by regulating STAT1/KDR/MMP9 and P53/BCL2L1/CASP3/7 pathways

Dihydroartemisinin (DHA), an effective antimalarial drug, has been widely investigated as an anti-tumor agent. Although previous studies have indicated the potential therapeutic effects of DHA on multiple malignancies, its detailed molecular mechanisms in gastric cancer (GC) are still undocumented. In the present study, we applied network pharmacology and bioinformatics (gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses) to obtain the collective targets of DHA and GC and analyzed their involvement in constructing a protein-protein interaction (PPI) network. The top 10% hub targets in this network were identified, and TCGA database was utilized for the single gene analysis of their correlation with the prognosis of GC. CCK8, EdU, Transwell, and flow cytometry analyses were conducted, and subcutaneous xenograft tumor models were constructed to assess the effects of DHA on the tumorigenesis and invasion of GC. Furthermore, the targets of DHA were verified by molecular docking, quantitative real-time PCR (qPCR) and western blot analyses in GC cells. The results indicated that the common targets of DHA and GC were enriched in multiple cancer-related pathways including KDR, STAT1 and apoptosis signaling pathways, where the core genes included KDR, MMP9, STAT1, TP53, CASP3/7 and BCL2L1. The lowered expression of KDR and increased expression of TP53 and CASP7 harbored a favorable survival for patients with GC patients. CASP7 showed a positive correlation with CASP3 but a negative correlation with KDR and could be regarded as an independent protective factor for overall survival in GC. Moreover, DHA treatment induced cell apoptosis and suppressed the cell proliferation, DNA synthesis, cycle progression and invasive capabilities both in vitro and in vivo. DHA also upregulated p53, CASP3, and cleaved-CASP3 and downregulated BCL2L1, MMP9, KDR, p-KDR, STAT1 and p-STAT1 in GC cell lines. In conclusion, DHA could suppress the tumorigenesis and invasion of GC by regulating STAT1/KDR/MMP9 and p53/BCL2L1/CASP3/7 pathways. Our findings might provide a novel approach for the treatment of GC.

Dihydroartemisinin: A Potential Natural Anticancer Drug

Dihydroartemisinin (DHA) is an active metabolite of artemisinin and its derivatives (ARTs), and it is an effective clinical drug widely used to treat malaria. Recently, the anticancer activity of DHA has attracted increasing attention. Nevertheless, there is no systematic summary on the anticancer effects of DHA. Notably, studies have shown that DHA exerts anticancer effects through various molecular mechanisms, such as inhibiting proliferation, inducing apoptosis, inhibiting tumor metastasis and angiogenesis, promoting immune function, inducing autophagy and endoplasmic reticulum (ER) stress. In this review, we comprehensively summarized the latest progress regarding the anticancer activities of DHA in cancer. Importantly, the underlying anticancer molecular mechanisms and pharmacological effects of DHA in vitro and in vivo are the focus of our attention. Interestingly, new methods to improve the solubility and bioavailability of DHA are discussed, which greatly enhance its anticancer efficacy. Remarkably, DHA has synergistic anti-tumor effects with a variety of clinical drugs, and preclinical and clinical studies provide stronger evidence of its anticancer potential. Moreover, this article also gives suggestions for further research on the anticancer effects of DHA. Thus, we hope to provide a strong theoretical support for DHA as an anticancer drug.

Targeting the p53-MDM2 pathway for neuroblastoma therapy: Rays of hope

Despite being the subject of extensive research and clinical trials, neuroblastoma remains a major therapeutic challenge in pediatric oncology. The p53 protein is a central safeguard that protects cells against genome instability and malignant transformation. Mutated TP53 (the gene encoding p53) is implicated in many human cancers, but the majority of neuroblastomas have wild type p53 with intact transcriptional function. In fact, the TP53 mutation rate does not exceed 1-2% in neuroblastomas. However, overexpression of the murine double minute 2 (MDM2) gene in neuroblastoma is relatively common, and leads to inhibition of p53. It is also associated with other non-canonical p53-independent functions, including drug resistance and increased translation of MYCN and VEGF mRNA. The p53-MDM2 pathway in neuroblastoma is also modulated at several different molecular levels, including via interactions with other proteins (MYCN, p14^ARF). In addition, the overexpression of MDM2 in tumors is linked to a poorer prognosis for cancer patients. Thus, restoring p53 function by inhibiting its interaction with MDM2 is a potential therapeutic strategy for neuroblastoma. A number of p53-MDM2 antagonists have been designed and studied for this purpose. This review summarizes the current understanding of p53 biology and the p53-dependent and -independent oncogenic functions of MDM2 in neuroblastoma, and also the regulation of the p53-MDM2 axis in neuroblastoma. This review also highlights the use of MDM2 as a molecular target for the disease, and describes the MDM2 inhibitors currently being investigated in preclinical and clinical studies. We also briefly explain the various strategies that have been used and future directions to take in the development of effective MDM2 inhibitors for neuroblastoma.

Emerging Nanopharmaceuticals and Nanonutraceuticals in Cancer Management

Nanotechnology is the science of nanoscale, which is the scale of nanometers or one billionth of a meter. Nanotechnology encompasses a broad range of technologies, materials, and manufacturing processes that are used to design and/or enhance many products, including medicinal products. This technology has achieved considerable progress in the oncology field in recent years. Most chemotherapeutic agents are not specific to the cancer cells they are intended to treat, and they can harm healthy cells, leading to numerous adverse effects. Due to this non-specific targeting, it is not feasible to administer high doses that may harm healthy cells. Moreover, low doses can cause cancer cells to acquire resistance, thus making them hard to kill. A solution that could potentially enhance drug targeting and delivery lies in understanding the complexity of nanotechnology. Engineering pharmaceutical and natural products into nano-products can enhance the diagnosis and treatment of cancer. Novel nano-formulations such as liposomes, polymeric micelles, dendrimers, quantum dots, nano-suspensions, and gold nanoparticles have been shown to enhance the delivery of drugs. Improved delivery of chemotherapeutic agents targets cancer cells rather than healthy cells, thereby preventing undesirable side effects and decreasing chemotherapeutic drug resistance. Nanotechnology has also revolutionized cancer diagnosis by using nanotechnology-based imaging contrast agents that can specifically target and therefore enhance tumor detection. In addition to the delivery of drugs, nanotechnology can be used to deliver nutraceuticals like phytochemicals that have multiple properties, such as antioxidant activity, that protect cells from oxidative damage and reduce the risk of cancer. There have been multiple advancements and implications for the use of nanotechnology to enhance the delivery of both pharmaceutical and nutraceutical products in cancer prevention, diagnosis, and treatment.

Dihydroartemisinin inhibits the migration of esophageal cancer cells by inducing autophagy

Esophageal cancer (EC) is a complex gastrointestinal malignancy and its global incidence rate ranks 7th among all cancer types. Due to its aggressive nature and the potential for early metastasis, the survival rates of patients with EC are poor. Dihydroartemisinin (DHA) is the primary active derivative of artemisinin, and, as well as its use as an anti-malarial, DHA has also exhibited antitumor activity in various cancer models, such as cholangiocarcinoma, head and neck carcinoma, and hepatocellular carcinoma cells. However, the molecular mechanisms underlying the antitumor effect of DHA in the treatment of EC remains poorly understood. The results of the present study demonstrated that DHA significantly inhibited the migration of TE-1 and Eca-109 EC cells in a dose-dependent manner by activating autophagy. DHA treatment also significantly reversed epithelial-mesenchymal transition (EMT) by downregulating the EMT-associated markers, N-cadherin and vimentin, and upregulating the expression of E-cadherin. Mechanistically, DHA treatment decreased Akt phosphorylation and inhibited the Akt/mTOR signaling pathway, leading to the activation of autophagy. The levels of the autophagy-associated proteins were suppressed and DHA-mediated inhibition of migration in EC cells was reversed when an active form of Akt was overexpressed. In conclusion, the present study demonstrated the potential value of DHA in the treatment of EC, and revealed the underlying mechanism by which FDHA inhibits cellular migration.

Artemisinin and its derivatives: a promising cancer therapy

The world is experiencing a cancer epidemic and an increase in the prevalence of the disease. Cancer remains a major killer, accounting for more than half a million deaths annually. There is a wide range of natural products that have the potential to treat this disease. One of these products is artemisinin; a natural product from Artemisia plant. The Nobel Prize for Medicine was awarded in 2015 for the discovery of artemisinin in recognition of the drug's efficacy. Artemisinin produces highly reactive free radicals by the breakdown of two oxygen atoms that kill cancerous cells. These cells sequester iron and accumulate as much as 1000 times in comparison with normal cells. Generally, chemotherapy is toxic to both cancerous cells and normal cells, while no significant cytotoxicity from artemisinin to normal cells has been found in more than 4000 case studies, which makes it far different than conventional chemotherapy. The pleiotropic response of artemisinin in cancer cells is responsible for growth inhibition by multiple ways including inhibition of angiogenesis, apoptosis, cell cycle arrest, disruption of cell migration, and modulation of nuclear receptor responsiveness. It is very encouraging that artemisinin and its derivatives are anticipated to be a novel class of broad-spectrum antitumor agents based on efficacy and safety. This review aims to highlight these achievements and propose potential strategies to develop artemisinin and its derivatives as a new class of cancer therapeutic agents.

Arenobufagin, isolated from toad venom, inhibited epithelial-to-mesenchymal transition and suppressed migration and invasion of lung cancer cells via targeting IKKβ/NFκB signal cascade

ETHNOPHARMACOLOGICAL RELEVANCE

Lung cancer is the leading cause of cancer incidence and mortality worldwide. Arenobufagin (Arg), a representative natural bufadienolide compound, is one of the major bioactive components isolated from toad venom ("Chan Su"named in Chinese to treat multifarious clinical neoplasms in China). However, the underlying molecular mechanisms that Arg inhibited the metastasis of lung cancer cells remain poorly understood.

MATERIALS AND METHODS

The mobility capacities of lung cancer cells treated with Arg were evaluated using wound healing assay. The anti-migratory and anti-invasive effects of Arg on lung cancer cells were investigated by transwell invasion assay and matrigel invasion assay. iTRAQ-labeled LC-MS proteomics was used to analyze the potential proteins related to metastasis in lung cancer cells treated with Arg and differentially-expressed proteins related to EMT and NFκB signaling cascade were further confirmed by Western blotting assay. The changed subcellular localization of p65 in lung cancer A549 and H1299 cells treated with Arg was detected by immunofluorescence staining. Molecular docking and molecular dynamic (MD) simulation assay were performed to verify the binding between Arg and IKKα/IKKβ. siRNA knockdown was used to check whether Arg inhibited EMT of lung cancer cells via targeting NFκB signaling cascade, which was further verified by in vivo study of lung cancer cell xenograft mice model and pulmonary metastasis mice model accompanying with immunohistochemical and hematoxylin-eosin (HE) staining.

RESULTS

Arg suppressed the wound closure of lung cancer cells using wound healing assay. Moreover, Arg significantly inhibited the migration and invasion of lung cancer cells by transwell invasion assay and matrigel invasion assay. 24 unique differentially-expressed proteins related to metastasis in lung cancer cells treated with Arg were identified using iTRAQ-labeled LC-MS proteomics and 14 differentially-expressed proteins related to EMT were further confirmed by Western blotting assay. Arg significantly decreased the phosphorylation of IKKβ, IκBα and p65 in the cytoplasm of lung cancer cells by Western blotting assay, and remarkably reduced the release of p65 from the cytoplasm to the nucleus. Arg could be bound in the ATP binding pocket of IKKα and IKKβ by molecular docking assay, and MD simulation assay further demonstrated that Arg binding to the ATP-binding pocket of IKKβ was very stable in 300 ns MD simulation, compared with the binding of Arg and IKKα. IKKβ/NFκB signaling cascade was also involved in the inhibitory effect of Arg on EMT of lung cancer cells by siRNA knockdown assay. The study of lung cancer cell xenograft mice model and pulmonary metastasis mice model in vivo indicated that Arg inhibited EMT and suppressed migration and invasion of lung cancer cells via downregulating IKKβ/NFκB signaling cascade.

CONCLUSION

In the present study, we explored the molecular mechanism of Arg prohibiting the metastasis of lung cancer cells in vitro and in vivo, which displayed Arg could target IKKβ to inactive NFκB signaling cascade and further change the expression of proteins related to EMT. These results highlight the potential of toad venom as a potential chemotherapeutic agent and warrant its development as the clinical therapy for lung cancer.

Dihydroartemisinin inhibits the tumorigenesis and metastasis of breast cancer via downregulating CIZ1 expression associated with TGF-β1 signaling

AIMS

Dihydroartemisinin (DHA) is currently considered as the promising cancer therapeutic drug. In this study, we aimed to investigate the anti-proliferative and anti-metastasis effects of DHA.

MAIN METHODS

Utilizing breast cancer cells MCF-7, MDA-MB-231 and BT549, cell proliferation, migration and invasion were detected. RT-qPCR was performed to detect CIZ1, TGF-β1 and Snail expression, and the interactions of these related molecules were analyzed by GeneMANIA database. Western blot detected CIZ1, TGF-β1/Smads signaling and Snail expression in DHA-treated cells, in TGFβ1-induced cells with enhanced metastatic capacity, and in cells treated with DHA plus TGFβ1/TGFβ1 inhibitor SD-208.

KEY FINDINGS

Results indicated DHA inhibited breast cancer cell proliferation and migration, with more potent effects compared with that of artemisinin. RT-qPCR and Western blot showed DHA inhibited CIZ1, TGF-β1 and Snail expression, and these molecules were shown to have protein-protein interactions by bioinformatics. Furthermore, TGFβ1-treatment enhanced MCF-7 migration and invasion, and CIZ1, TGF-β1/Smads signaling and snail activities; DHA, SD-208, combination of DHA and SD-208 reversed these conditions, preliminarily proving the cascade regulation between TGF-β1 signaling and CIZ1. MCF-7 xenografts model demonstrated the inhibition of DHA on tumor burden, and its mechanisms and well-tolerance in vivo; combination of DHA and SD-208 tried by us for the first time showed better treatment effects, but possible liver impairment made its use still keep cautious.

SIGNIFICANCE

DHA treatment inhibits the proliferation and metastasis of breast cancer, through suppressing TGF-β1/Smad signaling and CIZ1, suggesting the promising potential of DHA as a well-tolerated antitumor TGF-β1 pathway inhibitor.

Artesunate inhibits the mevalonate pathway and promotes glioma cell senescence

Glioma is a common brain malignancy for which new drug development is urgently needed because of radiotherapy and drug resistance. Recent studies have demonstrated that artemisinin (ARS) compounds can display antiglioma activity, but the mechanisms are poorly understood. Using cell lines and mouse models, we investigated the effects of the most soluble ARS analogue artesunate (ART) on glioma cell growth, migration, distant seeding and senescence and elucidated the underlying mechanisms. Artemisinin effectively inhibited glioma cell growth, migration and distant seeding. Further investigation of the mechanisms showed that ART can influence glioma cell metabolism by affecting the nuclear localization of SREBP2 (sterol regulatory element‐binding protein 2) and the expression of its target gene HMGCR (3‐hydroxy‐3‐methylglutaryl coenzyme A reductase), the rate‐limiting enzyme of the mevalonate (MVA) pathway. Moreover, ART affected the interaction between SREBP2 and P53 and restored the expression of P21 in cells expressing wild‐type P53, thus playing a key role in cell senescence induction. In conclusion, our study demonstrated the new therapeutic potential of ART in glioma cells and showed the novel anticancer mechanisms of ARS compounds of regulating MVA metabolism and cell senescence.

Potential applications of artemisinins in ocular diseases

Artemisinin, also named qinghaosu, is a family of sesquiterpene trioxane lactone originally derived from the sweet wormwood plant (Artemisia annua), which is a traditional Chinese herb that has been universally used as anti-malarial agents for many years. Evidence has accumulated during the past few years which demonstrated the protective effects of artemisinin and its derivatives (artemisinins) in several other diseases beyond malaria, including cancers, autoimmune disorders, inflammatory diseases, viral and other parasite-related infections. Recently, this long-considered anti-malarial agent has been proved to possess anti-oxidant, anti-inflammatory, anti-apoptotic and anti-excitotoxic properties, which make it a potential treatment option for the ocular environment. In this review, we first described the overview of artemisinins, highlighting the activity of artemisinins to other diseases beyond malaria and the mechanisms of these actions. We then emphasized the main points of published results of using artemisinins in targeting ocular disorders, including uveitis, retinoblastoma, retinal neurodegenerative diseases and ocular neovascularization. To conclude, we believe that artemisinins could also be used as a promising therapeutic drug for ocular diseases, especially retinal vascular diseases in the near future.

Naturally occurring anti-cancer compounds: shining from Chinese herbal medicine

Numerous natural products originated from Chinese herbal medicine exhibit anti-cancer activities, including anti-proliferative, pro-apoptotic, anti-metastatic, anti-angiogenic effects, as well as regulate autophagy, reverse multidrug resistance, balance immunity, and enhance chemotherapy in vitro and in vivo. To provide new insights into the critical path ahead, we systemically reviewed the most recent advances (reported since 2011) on the key compounds with anti-cancer effects derived from Chinese herbal medicine (curcumin, epigallocatechin gallate, berberine, artemisinin, ginsenoside Rg3, ursolic acid, silibinin, emodin, triptolide, cucurbitacin B, tanshinone I, oridonin, shikonin, gambogic acid, artesunate, wogonin, β-elemene, and cepharanthine) in scientific databases (PubMed, Web of Science, Medline, Scopus, and Clinical Trials). With a broader perspective, we focused on their recently discovered and/or investigated pharmacological effects, novel mechanism of action, relevant clinical studies, and their innovative applications in combined therapy and immunomodulation. In addition, the present review has extended to describe other promising compounds including dihydroartemisinin, ginsenoside Rh2, compound K, cucurbitacins D, E, I, tanshinone IIA and cryptotanshinone in view of their potentials in cancer therapy. Up to now, the evidence about the immunomodulatory effects and clinical trials of natural anti-cancer compounds from Chinese herbal medicine is very limited, and further research is needed to monitor their immunoregulatory effects and explore their mechanisms of action as modulators of immune checkpoints.

Targeting Membrane Receptors of Ovarian Cancer Cells for Therapy

Ovarian cancer is a leading cause of death worldwide from gynecological malignancies, mainly because there are few early symptoms and the disease is generally diagnosed at an advanced stage. In addition, despite the effectiveness of cytoreductive surgery for ovarian cancer and the high response rates to chemotherapy, survival has improved little over the last 20 years. The management of patients with ovarian cancer also remains similar despite studies showing striking differences and heterogeneity among different subtypes. It is therefore clear that novel targeted therapeutics are urgently needed to improve clinical outcomes for ovarian cancer. To that end, several membrane receptors associated with pivotal cellular processes and often aberrantly overexpressed in ovarian cancer cells have emerged as potential targets for receptor-mediated therapeutic strategies including specific agents and multifunctional delivery systems based on ligand-receptor binding. This review focuses on the profiles and potentials of such strategies proposed for ovarian cancer treatment and imaging.