Celastrol suppresses colorectal cancer via covalent targeting peroxiredoxin 1

Strategies for enhancing non-small cell lung cancer treatment: Integrating Chinese herbal medicines with epidermal growth factor receptor-tyrosine kinase inhibitors therapy

Non-small cell lung cancer (NSCLC) poses a global health threat, and epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) such as gefitinib, afatinib, and osimertinib have achieved significant success in clinical treatment. However, the emergence of resistance limits the long-term efficacy of these treatments, necessitating urgent exploration of novel EGFR-TKIs. This review provides an in-depth summary and exploration of the resistance mechanisms associated with EGFR-TKIs, with a specific focus on representative drugs like gefitinib, afatinib, and osimertinib. Additionally, the review introduces a therapeutic strategy involving the combination of Chinese herbal medicines (CHMs) and chemotherapy drugs, highlighting the potential role of CHMs in overcoming NSCLC resistance. Through systematic analysis, we elucidate the primary resistance mechanisms of EGFR-TKIs in NSCLC treatment, emphasizing CHMs as potential treatment medicines and providing a fresh perspective for the development of next-generation EGFR-TKIs. This comprehensive review aims to guide the application of CHMs in combination therapy for NSCLC management, fostering the development of more effective and comprehensive treatment modalities to ultimately enhance patient outcomes.

The anti-cancer mechanism of Celastrol by targeting JAK2/STAT3 signaling pathway in gastric and ovarian cancer

BACKGROUND

Celastrol is a natural triterpene exhibiting significant and extensive antitumor activity in a wide range of cancer. Due to unfavorable toxicity profile and undefined mechanism, Celastrol's application in clinical cancer therapy remains limited. Herein, we elucidate the pharmacological mechanism of Celastrol's anticancer effects, with a focus on STAT3 signaling pathway in cancers with high incidence of metastasis.

METHODS

The safety profile of Celastrol were assessed in mice. In vitro analysis was performed in gastric cancer and ovarian cancer to assess the cytotoxicity, induction of reactive oxygen species (ROS) of Celastrol using STAT3 knockout cancer cells. Effects of Celastrol on STAT3 activation and transcription activity, JAK2/STAT3 signaling protein expression were assessed. Additionally, proteomic contrastive analysis was performed to explore the molecular association of Celastrol with STAT3 deletion in cancer cells.

RESULTS

Celastrol has no obvious toxic effect at 1.5 mg/kg/day in a 15 days' administration. Celastrol inhibits tumor growth and increases ROS in a STAT3 dependent manner in gastric and ovarian cancer celllines. On molecular level, it downregulates IL-6 level and inhibits the JAK2/STAT3 signaling pathway by suppressing STAT3' activation and transcription activity. Proteomic contrastive analysis suggests a similar cellular mechanism of action between Celastrol and STAT3 deletion on regulating cancer progression pathways related to migration and invasion.

CONCLUSION

Our research elucidates the anti-cancer mechanism of Celastrol through targeting the JAK2/STAT3 signaling pathway in cancer with high incidence of metastasis. This study provides a solid theoretical basis for the application of Celastrol in cancer therapy.

Natural products for enhancing the sensitivity or decreasing the adverse effects of anticancer drugs through regulating the redox balance

Redox imbalance is reported to play a pivotal role in tumorigenesis, cancer development, and drug resistance. Severe oxidative damage is a general consequence of cancer cell responses to treatment and may cause cancer cell death or severe adverse effects. To maintain their longevity, cancer cells can rescue redox balance and enter a state of resistance to anticancer drugs. Therefore, targeting redox signalling pathways has emerged as an attractive and prospective strategy for enhancing the efficacy of anticancer drugs and decreasing their adverse effects. Over the past few decades, natural products (NPs) have become an invaluable source for developing new anticancer drugs due to their high efficacy and low toxicity. Increasing evidence has demonstrated that many NPs exhibit remarkable antitumour effects, whether used alone or as adjuvants, and are emerging as effective approaches to enhance sensitivity and decrease the adverse effects of conventional cancer therapies by regulating redox balance. Among them are several novel anticancer drugs based on NPs that have entered clinical trials. In this review, we summarize the synergistic anticancer effects and related redox mechanisms of the combination of NPs with conventional anticancer drugs. We believe that NPs targeting redox regulation will represent promising novel candidates and provide prospects for cancer treatment in the future.

Luteolin-7-diglucuronide, a novel PTP1B inhibitor, ameliorates hepatic stellate cell activation and liver fibrosis in mice

Liver fibrosis, one of the leading causes of morbidity and mortality worldwide, lacks effective therapy. The activation of hepatic stellate cells (HSCs) is the dominant event in hepatic fibrogenesis. Luteolin-7-diglucuronide (L7DG) is the major flavonoid extracted from Perilla frutescens and Verbena officinalis. Their beneficial effects in the treatment of liver diseases were well documented. In this study we investigated the anti-fibrotic activities of L7DG and the potential mechanisms. We established TGF-β1-activated mouse primary hepatic stellate cells (pHSCs) and human HSC line LX-2 as in vitro liver fibrosis models. Co-treatment with L7DG (5, 20, 50 μM) dose-dependently decreased TGF-β1-induced expression of fibrotic markers collagen 1, α-SMA and fibronectin. In liver fibrosis mouse models induced by CCl4 challenge alone or in combination with HFHC diet, administration of L7DG (40, 150 mg·kg-1·d-1, i.g., for 4 or 8 weeks) dose-dependently attenuated hepatic histopathological injury and collagen accumulation, decreased expression of fibrogenic genes. By conducting target prediction, molecular docking and enzyme activity detection, we identified L7DG as a potent inhibitor of protein tyrosine phosphatase 1B (PTP1B) with an IC50 value of 2.10 µM. Further studies revealed that L7DG inhibited PTP1B activity, up-regulated AMPK phosphorylation and subsequently inhibited HSC activation. This study demonstrates that the phytochemical L7DG may be a potential therapeutic candidate for the treatment of liver fibrosis.

Covalent binding of withanolides to cysteines of protein targets

Withanolides represent an important category of natural products with a steroidal lactone core. Many of them contain an α,β-unsaturated carbonyl moiety with a high reactivity toward sulfhydryl groups, including protein cysteine thiols. Different withanolides endowed with marked antitumor and anti-inflammatory have been shown to form stable covalent complexes with exposed cysteines present in the active site of oncogenic kinases (BTK, IKKβ, Zap70), metabolism enzymes (Prdx-1/6, Pin1, PHGDH), transcription factors (Nrf2, NFκB, C/EBPβ) and other structural and signaling molecules (GFAP, β-tubulin, p97, Hsp90, vimentin, Mpro, IPO5, NEMO, …). The present review analyzed the covalent complexes formed through Michael addition alkylation reactions between six major withanolides (withaferin A, physalin A, withangulatin A, 4β-hydroxywithanolide E, withanone and tubocapsanolide A) and key cysteine residues of about 20 proteins and the resulting biological effects. The covalent conjugation of the α,β-unsaturated carbonyl system of withanolides with reactive protein thiols can occur with a large set of soluble and membrane proteins. It points to a general mechanism, well described with the leading natural product withaferin A, but likely valid for most withanolides harboring a reactive (electrophilic) enone moiety susceptible to react covalently with cysteinyl residues of proteins. The multiplicity of reactive proteins should be taken into account when studying the mechanism of action of new withanolides. Proteomic and network analyses shall be implemented to capture and compare the cysteine covalent-binding map for the major withanolides, so as to identify the protein targets at the origin of their activity and/or unwanted effects. Screening of the cysteinome will help understanding the mechanism of action and designing cysteine-reactive electrophilic drug candidates.

Natural products with anti-tumorigenesis potential targeting macrophage

BACKGROUND

Inflammation is a risk factor for tumorigenesis. Macrophage, a subset of immune cells with high plasticity, plays a multifaceted role in this process. Natural products, which are bioactive compounds derived from traditional herbs or foods, have exhibited diverse effects on macrophages and tumorigenesis making them a valuable resource of drug discovery or optimization in tumor prevention.

PURPOSE

Provide a comprehensive overview of the various roles of macrophages in tumorigenesis, as well as the effects of natural products on tumorigenesis by modulating macrophage function.

METHODS

A thorough literature search spanning the past two decades was carried out using PubMed, Web of Science, Elsevier, and CNKI following the PRISMA guidelines. The search terms employed included "macrophage and tumorigenesis", "natural products, macrophages and tumorigenesis", "traditional Chinese medicine and tumorigenesis", "natural products and macrophage polarization", "macrophage and tumor related microenvironment", "macrophage and tumor signal pathway", "toxicity of natural products" and combinations thereof. Furthermore, certain articles are identified through the tracking of citations from other publications or by accessing the websites of relevant journals. Studies that meet the following criteria are excluded: (1) Articles not written in English or Chinese; (2) Full texts were not available; (3) Duplicate articles and irrelevant studies. The data collected was organized and summarized based on molecular mechanisms or compound structure.

RESULTS

This review elucidates the multifaceted effect of macrophages on tumorigenesis, encompassing process such as inflammation, angiogenesis, and tumor cell invasion by regulating metabolism, non-coding RNA, signal transduction and intercellular crosstalk. Natural products, including vitexin, ovatodiolide, ligustilide, and emodin, as well as herbal remedies, have demonstrated efficacy in modulating macrophage function, thereby attenuating tumorigenesis. These interventions mainly focus on mitigating the initial inflammatory response or modifying the inflammatory environment within the precancerous niche.

CONCLUSIONS

These mechanistic insights of macrophages in tumorigenesis offer valuable ideas for researchers. The identified natural products facilitate the selection of promising candidates for future cancer drug development.

Demethylzeylasteral exerts potent efficacy against non-small-cell lung cancer via the P53 signaling pathway

Lung cancer has one of the highest mortality rates worldwide, with non-small-cell lung cancer (NSCLC) constituting approximately 85% of all cases. Demethylzeylasteral (DEM), extracted from Tripterygium wilfordii Hook F, exhibits notable anti-tumor properties. In this study, we revealed that DEM could effectively induce NSCLC cell apoptosis. Specifically, DEM can dose-dependently suppress the viability and migration of human NSCLC cells. RNA-seq analysis revealed that DEM regulates the P53-signaling pathway, which was further validated by assessing crucial proteins involved in this pathway. Biacore analysis indicated that DEM has high affinity with the P53 protein. The CDX model demonstrated DEM's anti-tumor actions. This work provided evidence that DEM-P53 interaction stabilizes P53 protein and triggers downstream anti-tumor activities. These findings indicate that DEM treatment holds promise as a potential therapeutic approach for NSCLC, which warrants further clinical assessment in patients with NSCLC.

Redirecting Tumor Evolution with Nanocompiler Precision for Enhanced Therapeutic Outcomes

Precisely programming the highly plastic tumor expression profile to render it devoid of drug resistance and metastatic potential presents immense challenges. Here, a transformative nanocompiler designed to reprogram and stabilize the mutable state of tumor cells is introduced. This nanocompiler features a trio of components: 2-deoxy-d-glucose-modified lipid nanoparticles to inhibit glucose uptake, iron oxide nanoparticles to induce oxidative stress, and a deubiquitinase inhibitor to block adaptive protein profile changes in tumor cells. By specifically targeting the hypermetabolic nature of tumors, this approach disrupted their energy production, ultimately fostering a state of vulnerability and impeding their ability to adapt and resist. The results of this study indicate a substantial reduction in tumor growth and metastasis, thus demonstrating the potential of this strategy to manipulate tumor protein expression and fate. This proactive nanocompiler approach promises to steer cancer therapy toward more effective and lasting outcomes.

Celastrol induces ferroptosis by suppressing RRM2 in hepatocellular carcinoma

Introduction and Objectives

Ferroptosis is a novel form of cell death driven by iron dependence and lipid peroxidation, presenting a promising potential as an innovative strategy for cancer treatment. Celastrol (Cel) is particularly effective in inducing ferroptosis, but its molecular mechanism remains unclear. The study aims to elucidate the potential mechanism through both in vitro and in vivo experiments.

Materials and methods

CCK-8 assay, Western blot analysis and measurements of reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH) were performed to investigate how Cel inhibits the proliferation of hepatocellular carcinoma (HCC) cells via the ferroptosis mechanism. Bioinformatics analysis based on the TCGA-LIHC and FerrDb databases was performed to identify the target gene RRM2, and molecular docking-simulated binding between RRM2 and Cel. The role of RRM2 in the effects of Cel was determined through lentiviral transfection, Transwell assays, and in vivo experiments.

Results

Cel inhibited HCC cell proliferation via the ferroptosis pathway. Inhibition RRM2 significantly reduces mTOR protein phosphorylation, while overexpressing RRM2 can attenuate theeffects of Cel on the proliferation, migration, invasion, and ferroptosis induction of HCC cells. The result of in vivo experiments in nude mice demonstrated that Cel inhibited tumor growth without adversely affecting liver and kidney function indicators. Immunohistochemistry and Western blot analyses revealed that Cel activated the key proteins in the ferroptosis pathway and affected crucial indicators such as malondialdehyde (MDA) and glutathione (GSH).

Conclusion

In this study, we clarifiy the molecular mechanism of Cel, thus broadening its clinical applications for treating various cancer types, including liver cancer.

Thermostability-assisted limited proteolysis-coupled mass spectrometry for capturing drug target proteins and sites

BACKGROUND

Identifying drug-binding targets and their corresponding sites is crucial for drug discovery and mechanism studies. Limited proteolysis-coupled mass spectrometry (LiP-MS) is a sophisticated method used for the detection of compound and protein interactions. However, in some cases, LiP-MS cannot identify the target proteins due to the small structure changes or the lack of enrichment of low-abundant protein. To overcome this drawback, we developed a thermostability-assisted limited proteolysis-coupled mass spectrometry (TALiP-MS) approach for efficient drug target discovery.

RESULTS

We proved that the novel strategy, TALiP-MS, could efficiently identify target proteins of various ligands, including cyclosporin A (a calcineurin inhibitor), geldanamycin (an HSP90 inhibitor), and staurosporine (a kinase inhibitor), with accurately recognizing drug-binding domains. The TALiP protocol increased the number of target peptides detected in LiP-MS experiments by 2- to 8-fold. Meanwhile, the TALiP-MS approach can not only identify both ligand-binding stability and destabilization proteins but also shows high complementarity with the thermal proteome profiling (TPP) and machine learning-based limited proteolysis (LiP-Quant) methods. The developed TALiP-MS approach was applied to identify the target proteins of celastrol (CEL), a natural product known for its strong antioxidant and anti-cancer angiogenesis effect. Among them, four proteins, MTHFD1, UBA1, ACLY, and SND1 were further validated for their strong affinity to CEL by using cellular thermal shift assay. Additionally, the destabilized proteins induced by CEL such as TAGLN2 and CFL1 were also validated.

SIGNIFICANCE

Collectively, these findings underscore the efficacy of the TALiP-MS method for identifying drug targets, elucidating binding sites, and even detecting drug-induced conformational changes in target proteins in complex proteomes.

Terpenoids from quinoa reverse drug resistance of colon cancer by upregulating miR-495-3p

BACKGROUND

Quinoa contains far more nutrients than any traditional grain crop. It is known that terpenoids in quinoa have anti-inflammatory and antitumor effects, but their role in reversing drug resistance remains unclear.

RESULTS

Our previous studies showed that quinoa-derived terpenoid compounds (QBT) can inhibit the occurrence and development of colon cancer. This study further indicates that QBT markedly reverse drug resistance of colon cancer. The results showed that QBT combined with 5-fluorouracil (5-Fu) treatment significantly enhanced the chemotherapy sensitivity of HCT-8/Fu, compared with 5-Fu treatment alone. Moreover, we found that QBT significantly reduced the expression of drug-resistant proteins (P-gp, MRP1, BCRP), and increased the accumulation of chemotherapy drugs. Taking P-gp as the target for biogenesis prediction analysis, results showed that upregulation of miR-495-3p enhanced the chemosensitivity of drug-resistant HCT-8/Fu cells. Besides, the results showed that miR-495-3p was abnormally methylated in HCT-8/Fu compared with HCT-8 colon cancer cells. The expression of methyltransferases DNMT1, DNMT3a and DNMT3b was abnormal. After QBT treatment, the expression level of methyltransferases returned to normal. In addition, the QBT + 5Fu group showed inhibition of tumors in nude mice.

CONCLUSION

QBT treatment downregulated the expression of drug-resistant protein P-gp by inhibiting the methylation of miR-495-3p, and enhanced the accumulation of 5-Fu in vivo, which in turn reversed its chemoresistance. This suggests that QBT has potential ability as a new drug-resistance reversal agent in colorectal cancer. © 2024 Society of Chemical Industry.

Celastrol nano-emulsions selectively regulate apoptosis of synovial macrophage for alleviating rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune inflammation. Excessive proliferation and inadequate apoptosis of synovial macrophages are the crucial events of RA. Therefore, delivering therapeutic molecules to synovial macrophages specifically to tackle apoptotic insufficiency probably can be an efficient way to reduce joint inflammation and bone erosion. Based on the characteristics of dextran sulphate (DS) specifically binding scavenger receptor A (SR-A) on macrophage and celastrol (CLT) inducing apoptosis, we designed synovial macrophage-targeted nano-emulsions encapsulated with CLT (SR-CLTNEs) and explored their anti-RA effect. After intravenous injection, fluorescence-labelled SR-CLTNEs successfully targeted inflammatory joints and synovial macrophages in a mouse model of RA, with the macrophage targeting efficiency of SR-CLTNEs, CLTNEs and free DID was 20.53%, 13.93% and 9.8%, respectively. In vivo and in vitro studies showed that SR-CLTNEs effectively promoted the apoptosis of macrophages, reshaped the balance between apoptosis and proliferation, and ultimately treated RA in a high efficiency and low toxicity manner. Overall, our work demonstrates the efficacy of using SR-CLTNEs as a novel nanotherapeutic approach for RA therapy and the great translational potential of SR-CLTNEs.

13-Oxyingenol-dodecanoate inhibits the growth of non-small cell lung cancer cells by targeting ULK1

Lung cancer is the leading cause of cancer deaths worldwide. Non-small cell lung cancer (NSCLC) accounts for 80-85% of all lung cancers. Euphorbia kansui yielded 13-oxyingenol-dodecanoate (13OD), an ingenane-type diterpenoid, which had a strong cytotoxic effect on NSCLC cells. The underlying mechanism and potential target, however, remained unknown. The study found that 13OD effectively inhibited the cell proliferation and colony formation of NSCLC cells (A549 and H460 cells), with less toxicity in normal human lung epithelial BEAS-2B cells. Moreover, 13OD can cause mitochondrial dysfunction, and apoptosis in NSCLC cells. Mechanistically, the transcriptomics results showed that differential genes were mainly enriched in the mTOR and AMPK signaling pathways, which are closely related to cellular autophagy, the related indicators were subsequently validated. Additionally, bafilomycin A1 (Baf A1), an autophagy inhibitor, reversed the mitochondrial damage caused by 13OD. Furthermore, the Omics and Text-based Target Enrichment and Ranking (OTTER) method predicted ULK1 as a potential target of 13OD against NSCLC cells. This hypothesis was further confirmed using molecular docking, the cellular thermal shift assay (CETSA), and Western blot analysis. Remarkably, ULK1 siRNA inhibited 13OD's toxic activity in NSCLC cells. In line with these findings, 13OD was potent and non-toxic in the tumor xenograft model. Our findings suggested a possible mechanism for 13OD's role as a tumor suppressor and laid the groundwork for identifying targets for ingenane-type diterpenoids.

Celastrol Ameliorates Neuronal Mitochondrial Dysfunction Induced by Intracerebral Hemorrhage via Targeting cAMP-Activated Exchange Protein-1

Mitochondrial dysfunction contributes to the development of secondary brain injury (SBI) following intracerebral hemorrhage (ICH) and represents a promising therapeutic target. Celastrol, the primary active component of Tripterygium wilfordii, is a natural product that exhibits mitochondrial and neuronal protection in various cell types. This study aims to investigate the neuroprotective effects of celastrol against ICH-induced SBI and explore its underlying mechanisms. Celastrol improves neurobehavioral and cognitive abilities in mice with autologous blood-induced ICH, reduces neuronal death in vivo and in vitro, and promotes mitochondrial function recovery in neurons. Single-cell nuclear sequencing reveals that the cyclic adenosine monophosphate (cAMP)/cAMP-activated exchange protein-1 (EPAC-1) signaling pathways are impacted by celastrol. Celastrol binds to cNMP (a domain of EPAC-1) to inhibit its interaction with voltage-dependent anion-selective channel protein 1 (VDAC1) and blocks the opening of mitochondrial permeability transition pores. After neuron-specific knockout of EPAC1, the neuroprotective effects of celastrol are diminished. In summary, this study demonstrates that celastrol, through its interaction with EPAC-1, ameliorates mitochondrial dysfunction in neurons, thus potentially improving SBI induced by ICH. These findings suggest that targeting EPAC-1 with celastrol can be a promising therapeutic approach for treating ICH-induced SBI.

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.

Discovery of Urea Derivatives of Celastrol as Selective Peroxiredoxin 1 Inhibitors against Colorectal Cancer Cells

Peroxiredoxin (PRDX1) is a tumor-overexpressed antioxidant enzyme for eliminating excessive reactive oxygen species (ROS) to protect tumor cells from oxidative damage. Herein, a series of celastrol urea derivatives were developed based on its cocrystal structure with PRDX1, with the aim of pursuing a PRDX1-specific inhibitor. Among them, derivative 15 displayed potent anti-PRDX1 activity (IC50 = 0.35 μM) and antiproliferative potency against colon cancer cells. It covalently bound to Cys-173 of PRDX1 (KD = 0.37 μM), which was secured by the cocrystal structure of PRDX1 with an analogue of 15 while exhibiting weak inhibitory effects on PRDX2-PRDX6 (IC50 > 50 μM), indicating excellent PRDX1 selectivity. Treatment with 15 dose-dependently decreased the mitochondria membrane potential of SW620 cells, probably due to ROS induced by PRDX1 inhibition, leading to cell apoptosis. In colorectal cancer cell xenograft model, it displayed potent antitumor efficacy with superior safety to celastrol. Collectively, 15 represents a promising PRDX1 selective inhibitor for the development of anticolorectal cancer agents.

Iron Supplementation Increases Tumor Burden and Alters Protein Expression in a Mouse Model of Human Intestinal Cancer

Iron supplements are widely consumed. However, excess iron may accelerate intestinal tumorigenesis. To determine the effect of excess iron on intestinal tumor burden and protein expression changes between tumor and normal tissues, ApcMin/+ mice were fed control (adequate) and excess iron (45 and 450 mg iron/kg diet, respectively; n = 9/group) for 10 wk. Tumor burden was measured, and two-dimensional fluorescence difference gel electrophoresis was used to identify differentially expressed proteins in tumor and normal intestinal tissues. There was a significant increase (78.3%; p ≤ 0.05) in intestinal tumor burden (mm2/cm) with excess iron at wk 10. Of 980 analyzed protein spots, 69 differentially expressed (p ≤ 0.05) protein isoforms were identified, representing 55 genes. Of the isoforms, 56 differed (p ≤ 0.05) between tumor vs. normal tissues from the adequate iron group and 23 differed (p ≤ 0.05) between tumors from the adequate vs. excess iron. Differentially expressed proteins include those involved in cell integrity and adaptive response to reactive oxygen species (including, by gene ID: ANPEP, DPP7, ITGB1, PSMA1 HSPA5). Biochemical pathway analysis found that iron supplementation modulated four highly significant (p ≤ 0.05) functional networks. These findings enhance our understanding of interplay between dietary iron and intestinal tumorigenesis and may help develop more specific dietary guidelines regarding trace element intake.

Dihydrocelastrol induces cell death and suppresses angiogenesis through BCR/AP-1/junb signalling in diffuse large B cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma. Although treatment options have improved, a large proportion of patients show low survival rates, highlighting an urgent need for novel therapeutic strategies. The aim of this study was to investigate the efficacy of the new small-molecule compound dihydrocelastrol (DHCE), acquired through the structural modification of celastrol (CE), in the treatment of DLBCL. DHCE showed potent anti-lymphoma efficacy and synergistic effects with doxorubicin. DHCE triggered DLBCL cell apoptosis and G0/G1-phase blockade, thereby hindering angiogenesis. DHCE inhibited B-cell receptor cascade signalling and Jun B and p65 nuclear translocation, thereby suppressing pro-tumourigenic signalling. Finally, DHCE exerted lower toxicity than CE, which showed severe hepatic, renal, and reproductive toxicity in vivo. Our findings support further investigation of the clinical efficacy of DHCE against DLBCL.

In silico analysis of small molecule compounds based on pharmacophore- and backbone-leaping peroxiredoxin 1 (PRDX1) inhibitors

Abnormal expression of PRDX has been found to play a significant role in the growth of colorectal cancer and other types of tumors. Despite the identification of several PRDX1 inhibitory compounds in recent years, none of them have been utilized in clinical treatments. Therefore, we conducted a virtual screening of 210,331 small molecules from the SPECS library using PRDX1 and multiple methods. From this screening, we identified 13 compounds with the highest scores from the molecular docking analysis. To further validate the accuracy of our pharmacophore model, we constructed a structure-based pharmacophore model and analyzed the receiver operating characteristic curve (ROC curve). Through this process, we selected nine compounds using skeleton jumping and virtual screening based on the highest pharmacophore model scores. Subsequently, we examined the ADMET properties of these nine compounds to assess their drug-forming potential, resulting in three compounds with the best drug properties. Finally, we assessed the binding stability of these three candidate molecules to proteins using molecular dynamics and MM-PBSA calculations. After a comprehensive evaluation, we found that compounds 6 and 9 formed stable complexes with PRDX1 proteins and could potentially serve as competitive inhibitors of PRDX1 substrates.Communicated by Ramaswamy H. Sarma.

LncFASA promotes cancer ferroptosis via modulating PRDX1 phase separation

Ferroptosis, a unique type of non-apoptotic cell death resulting from iron-dependent lipid peroxidation, has a potential physiological function in tumor suppression, but its underlying mechanisms have not been fully elucidated. Here, we report that the long non-coding RNA (lncRNA) LncFASA increases the susceptibility of triple-negative breast cancer (TNBC) to ferroptosis. As a tumor suppressor, LncFASA drives the formation of droplets containing peroxiredoxin1 (PRDX1), a member of the peroxidase family, resulting in the accumulation of lipid peroxidation via the SLC7A11-GPX4 axis. Mechanistically, LncFASA directly binds to the Ahpc-TSA domain of PRDX1, inhibiting its peroxidase activity by driving liquid-liquid phase separation, which disrupts intracellular ROS homeostasis. Notably, high LncFASA expression indicates favorable overall survival in individuals with breast cancer, and LncFASA impairs the growth of breast xenograft tumors by modulating ferroptosis. Together, our findings illustrate the crucial role of this lncRNA in ferroptosis-mediated cancer development and provide new insights into therapeutic strategies for breast cancer.

Breviscapine protects against pathological cardiac hypertrophy by targeting FOXO3a-mitofusin-1 mediated mitochondrial fusion

Forkhead box O3a (FOXO3a)-mediated mitochondrial dysfunction plays a pivotal effect on cardiac hypertrophy and heart failure (HF). However, the role and underlying mechanisms of FOXO3a, regulated by breviscapine (BRE), on mitochondrial function in HF therapy remain unclear. This study reveals that BRE-induced nuclear translocation of FOXO3a facilitates mitofusin-1 (MFN-1)-dependent mitochondrial fusion in cardiac hypertrophy and HF. BRE effectively promotes cardiac function and ameliorates cardiac remodeling in pressure overload-induced mice. In addition, BRE mitigates phenylephrine (PE)-induced cardiac hypertrophy in cardiomyocytes and fibrosis remodeling in fibroblasts by inhibiting ROS production and promoting mitochondrial fusion, respectively. Transcriptomics analysis underscores the close association between the FOXO pathway and the protective effect of BRE against HF, with FOXO3a emerging as a potential target of BRE. BRE potentiates the nuclear translocation of FOXO3a by attenuating its phosphorylation, other than its acetylation in cardiac hypertrophy. Mechanistically, over-expression of FOXO3a significantly inhibits cardiac hypertrophy and mitochondrial injury by promoting MFN-1-mediated mitochondrial fusion. Furthermore, BRE demonstrates its ability to substantially curb cardiac hypertrophy, reduce mitochondrial ROS production, and enhance MFN-1-mediated mitochondrial fusion through a FOXO3a-dependent mechanism. In conclusion, nuclear FOXO3a translocation induced by BRE presents a successful therapeutic avenue for addressing cardiac hypertrophy and HF through promoting MFN-1-dependent mitochondrial fusion.

[Demethylzeylasteral inhibits proliferation, migration and invasion and promotes apoptosis of non-small cell lung cancer cells by inhibiting the AKT/CREB signaling pathway]

OBJECTIVE

To investigate the mechanism underlying the inhibitory effects of Demethylzeylasteral (T-96) on non-small cell lung cancer (NSCLC) cells.

METHODS

We first examined the effects of different concentrations (1, 3, 10, and 30 μmol/L) of demethylzeylasteral on morphology and cell number of A549 and H1299 cells. The changes in proliferation, cell viability, migration, invasion, and apoptosis of A549 and H1299 cells following demethylzeylasteral treatment were detected using clone formation, CCK-8, cell scratch, Transwell, and flow cytometric assays, and the effect of SC79 treatment against demethylzeylasteral-induced cell apoptosis was assessed. Western blotting was performed to detect the changes in expressions of E-cadherin, N-cadherin, vimentin, Bax, Bcl-2 and cleaved caspase-3 and phosphorylation of AKT/CREB in demethylzeylasteral-treated A549 and H1299 cells and the cellular expressions of apoptotic proteins following treatment with both demethylzeylasteral and SC79.

RESULTS

T-96 treatment caused elongation of the cell body and widening of the intercellular space and significantly inhibited cell viability, proliferation, migration and invasion of A549 and H1299 cells (P < 0.05). Flow cytometry showed that demethylzeylasteral induced apoptosis in both A549 and H1299 cells, whereas SC79 treatment obviously attenuated its pro-apoptotic effect (P < 0.05). Western blotting revealed up-regulated expressions of Bax and cleaved caspase-3 proteins and lowered Bcl-2 expression level in demethylzeylasteral-treated A549 and H1299 cells, but cotreatment with SC79 obviously attenuated the expressions of the apoptotic proteins. T-96 significantly up-regulated the expression level of E-cadherin, down-regulated the expressions of N-cadherin and vimentin, and inhibited the phosphorylation of AKT and CREB in the two cell lines (P < 0.05).

CONCLUSION

T-96 inhibits the proliferation, migration and invasion and induces apoptosis of NSCLC cells possibly by inhibiting the AKT/CREB signaling pathway.

Novel GSH-responsive prodrugs derived from indole-chalcone and camptothecin trigger apoptosis and autophagy in colon cancer

Antineoplastic agents that target tubulin have shown efficacy as chemotherapeutic drugs, yet they are often constrained by multidrug resistance (MDR) and unwanted side effects. A multi-targeted strategy demonstrates great potency in reducing toxicity and enhancing efficacy and provides an alternative way for attenuating MDR. In this study, a series of dual-targeted anti-cancer agents based on indole-chalcone derivatives and the camptothecin (CPT) scaffold were synthesized. Among them, 14-1 demonstrated superior anti-proliferative activity than its precursor 13-1, CPT or their physical mixtures against tested cancer cells, including multidrug-resistant variants, while exhibited moderate cytotoxicity toward human normal cells. Mechanistic studies revealed that 14-1 acted as a glutathione-responsive prodrug, inducing apoptosis by substantially enhancing intracellular uptake of CPT, inhibiting tubulin polymerization, increasing the accumulation of intracellular reactive oxygen species, and initiating a mitochondrion-dependent apoptotic pathway. Moreover, 14-1 notably induced autophagy and suppressed topoisomerase I activity to further promote apoptosis. Importantly, 14-1 displayed potent inhibitory effect on tumor growth in paclitaxel (PTX)-resistant colorectal cancer (HCT-116/PTX) xenograft models without inducing obvious toxicity compared with CPT- or combo-treated group. These results suggest that 14-1 holds promise as a novel candidate for anti-cancer therapy, particularly in PTX-resistant cancers.

Celastrol Pyrazine Derivative Alleviates Silicosis Progression via Inducing ROS-Mediated Apoptosis in Activated Fibroblasts

Silicosis is a complex occupational disease without recognized effective treatment. Celastrol, a natural product, has shown antioxidant, anti-inflammatory, and anti-fibrotic activities, but the narrow therapeutic window and high toxicity severely limit its clinical application. Through structural optimization, we have identified a highly efficient and low-toxicity celastrol derivative, CEL-07. In this study, we systematically investigated the therapeutic potential and underlying mechanisms of CEL-07 in silicosis fibrosis. By constructing a silicosis mouse model and analyzing with HE, Masson, Sirius Red, and immunohistochemical staining, CEL-07 significantly prevented the progress of inflammation and fibrosis, and it effectively improved the lung respiratory function of silicosis mice. Additionally, CEL-07 markedly suppressed the expression of inflammatory factors (IL-6, IL-1α, TNF-α, and TNF-β) and fibrotic factors (α-SMA, collagen I, and collagen III), and promoted apoptosis of fibroblasts by increasing ROS accumulation. Moreover, bioinformatics analysis combined with experimental validation revealed that CEL-07 inhibited the pathways associated with inflammation (PI3K-AKT and JAK2-STAT3) and the expression of apoptosis-related proteins. Overall, these results suggest that CEL-07 may serve as a potential candidate for the treatment of silicosis.

Curcusinol from the fruit of Carex baccans with antibacterial activity against multidrug-resistant strains

ETHNOPHARMACOLOGICAL RELEVANCE

Carex baccans, known as Shan-Bai-Zi or Ye-Gao-Liang in China, is a traditional medicinal herb used by several ethnic groups in Yunnan Province. It is utilized for the treatment of wound infections, ulcers, and dysentery. However, there is currently a dearth of research reports on its antimicrobial potential.

AIM OF THE STUDY

The substance basis of the antimicrobial activity of C. baccans will be unveiled, and the in vitro and in vivo antibacterial activities against multidrug-resistant bacteria of its major active compounds, as well as their preliminary mechanisms of action, will be investigated.

MATERIALS AND METHODS

An antibacterial bioactivity-guided isolation method was used to isolate and identify the active compound curcusinol from C. baccans. UPLC-DAD-MS was employed for the quantitative analysis of curcusinol. The antibacterial activity, resistance profile, synergistic effects, anti-biofilm activity, and potential mechanisms of action of curcusinol against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), and other multidrug-resistant bacteria (Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii) were investigated using various methods, including the broth microdilution method, scanning electron microscopy, time kill assay, multi-generational resistance induction assay, checkerboard synergy assay, anti-biofilm assay, and metabolomics. Furthermore, the therapeutic efficacy of curcusinol was assessed in vivo by establishing an animal skin wound infection model of MRSA.

RESULTS

Curcusinol was isolated from the fruit of C. baccans, which accounts for 3.1% of the dry weight of the fruit. Curcusinol exhibited significant bactericidal and anti-biofilm activities against antibiotic-resistant Gram-positive bacteria in vitro. Furthermore, curcusinol acted as an antibiotic adjuvant to enhance the activity of various commonly used antibiotics against both Gram-positive and Gram-negative antibiotic-resistant bacteria without cytotoxicity to mammalian cells (A549 and RAW264.7) at 64 μM. Moreover, curcusinol affected arginine biosynthesis, cysteine and methionine metabolism, and alanine, aspartate, and glutamate metabolism significantly in MRSA cells under stress. Additionally, curcusinol effectively treated MRSA-infected mouse skin wounds and accelerated wound healing in vivo.

CONCLUSIONS

The results of this study not only support the traditional uses of C. baccans but also demonstrate that its major active compound, curcusinol, is an effective plant-derived bactericidal agent and antibacterial adjuvant with potential applications in the treatment of skin infections.

Celastrol Elicits Antitumor Effects through Inducing Immunogenic Cell Death and Downregulating PD-L1 in ccRCC

BACKGROUND

Targeting immunogenic cell death (ICD) is considered a promising therapeutic strategy for cancer. However, the commonly identified ICD inducers promote the expression of programmed cell death ligand 1 (PD-L1) in tumor cells, thus aiding them to evade the recognition and killing by the immune system. Therefore, the finding of novel ICD inducers to avoid enhanced PD-L1 expression is of vital significance for cancer therapy. Celastrol (CeT), a triterpene isolated from Tripterygium wilfordii Hook. F induces various forms of cell death to exert anti-cancer effects, which may make celastrol an attractive candidate as an inducer of ICD.

METHODS

In the present study, bioinformatics analysis was combined with experimental validation to explore the underlying mechanism by which CeT induces ICD and regulates PD-L1 expression in clear cell renal cell carcinoma (ccRCC).

RESULTS

The results showed that EGFR, IKBKB, PRKCQ and MAPK1 were the crucial targets for CeT-induced ICD, and only MAPK1 was an independent prognostic factor for the overall survival (OS) of ccRCC patients. In addition, CeT triggered autophagy and up-regulated the expressions of HMGB1 and CRT to induce ICD in 786-O cells in vitro. Importantly, CeT can down-regulate PD-L1 expression through activating autophagy. At the molecular level, CeT suppressed PD-L1 via the inhibition of MAPK1 expression. Immunologically, the core target of celastrol, MAPK1, was tightly correlated with CD8+ T cells and CD4+ T cells in ccRCC.

CONCLUSION

These findings indicate that CeT not only induces ICD but also suppresses PD-L1 by down-regulating MAPK1 expression, which will provide an attractive strategy for ccRCC immunotherapy.

Monotropein Induced Apoptosis and Suppressed Cell Cycle Progression in Colorectal Cancer Cells

OBJECTIVE

To determine whether monotropein has an anticancer effect and explore its potential mechanisms against colorectal cancer (CRC) through network pharmacology and molecular docking combined with experimental verification.

METHODS

Network pharmacology and molecular docking were used to predict potential targets of monotropein against CRC. Cell counting kit assay, plate monoclonal assay and microscopic observation were used to investigate the antiproliferative effects of monotropein on CRC cells HCT116, HT29 and LoVo. Flow cytometry and scratch assay were used to analyze apoptosis and cell cycle, as well as cell migration, respectively in HCT116, HT29, and LoVo cells. Western blotting was used to detect the expression of proteins related to apoptosis, cell cycle, and cell migration, and the expression of proteins key to the Akt pathway.

RESULTS

The Gene Ontology and Reactome enrichment analyses indicated that the anticancer potential of monotropein against CRC might be involved in multiple cancer-related signaling pathways. Among these pathways, RAC-beta serine/threonine-protein kinase (Akt1, Akt2), cyclin-dependent kinase 6 (CDK6), matrix metalloproteinase-9 (MMP9), epidermal growth factor receptor (EGFR), cell division control protein 42 homolog (CDC42) were shown as the potential anticancer targets of monotropein against CRC. Molecular docking suggested that monotropein may interact with the 6 targets (Akt1, Akt2, CDK6, MMP9, EGFR, CDC42). Subsequently, cell activity of HCT116, HT29 and LoVo cell lines were significantly suppressed by monotropein (P<0.05). Furthermore, our research revealed that monotropein induced cell apoptosis by inhibiting Bcl-2 and increasing Bax, induced G1-S cycle arrest in colorectal cancer by decreasing the expressions of CyclinD1, CDK4 and CDK6, inhibited cell migration by suppressing the expressions of CDC42 and MMP9 (P<0.05), and might play an anticancer role through Akt signaling pathway.

CONCLUSION

Monotropein exerts its antitumor effects primarily by arresting the cell cycle, causing cell apoptosis, and inhibiting cell migration. This indicates a high potential for developing novel medication for treating CRC.

Dual role of PRDX1 in redox-regulation and tumorigenesis: Past and future

Tumour cells often display an active metabolic profile, leading to the intracellular accumulation of reactive oxygen species. As a member of the peroxidase family, peroxiredoxin 1 (PRDX1) functions generally in protecting against cell damage caused by H2O2. Additionally, PRDX1 plays a role as a molecular chaperone in various malignant tumours, exhibiting either tumour-promoting or tumour-suppressing effects. Currently, PRDX1-targeting drugs have demonstrated in vitro anticancer effects, indicating the potential of PRDX1 as a molecular target. Here we discussed the diverse functions of PRDX1 in tumour biology and provided a comprehensive analysis of the therapeutic potential of targeting PRDX1 signalling across various types of cancer.

Recent advances in small molecule and peptide inhibitors of glucose-regulated protein 78 for cancer therapy

Glucose-regulated protein 78 (GRP78) is one of key endoplasmic reticulum (ER) chaperone proteins that regulates the unfolded protein response (UPR) to maintain ER homeostasis. As a core factor in the regulation of the UPR, GRP78 takes a critical part in the cellular processes required for tumorigenesis, such as proliferation, metastasis, anti-apoptosis, immune escape and chemoresistance. Overexpression of GRP78 is closely correlated with tumorigenesis and poor prognosis in various malignant tumors. Targeting GRP78 is regarded as a potentially promising therapeutic strategy for cancer therapy. Although none of the GRP78 inhibitors have been approved to date, there have been several studies of GRP78 inhibitors. Herein, we comprehensively review the structure, physiological functions of GRP78 and the recent progress of GRP78 inhibitors, and discuss the structures, in vitro and in vivo efficacies, and merits and demerits of these inhibitors to inspire further research. Additionally, the feasibility of GRP78-targeting proteolysis-targeting chimeras (PROTACs), disrupting GRP78 cochaperone interactions, or covalent inhibition are also discussed as novel strategies for drugs discovery targeting GRP78, with the hope that these strategies can provide new opportunities for targeted GRP78 antitumor therapy.

Unraveling the mechanism of quercetin alleviating perfluorooctane sulfonate-induced apoptosis in grass carp (Ctenopharyngodon idellus) hepatocytes: AMPK/mTOR-mediated mitophagy

Exposure to persistent new organic pollutants in the environment often leads to high mortality and causes serious economic losses to the aquaculture industry. Currently, perfluorooctane sulfonate (PFOS) is persistent and bio-accumulative in the environment, causing potential risks to aquatic ecosystems, but its toxicity mechanism to aquatic organisms is still unclear. As a natural flavonoid compound, quercetin (QU) has many biological activities such as anti-oxidation, anti-inflammatory, anti-apoptosis and immune regulation. Whether it can be used as a candidate medicine to alleviate PFOS toxicity needs to be further explored. Therefore, in this study, we treated (Ctenopharyngodon idellus) grass carp hepatocytes (L8824) with PFOS (200 μM) and/or QU (60 μM) for 24 h. The results showed that PFOS significantly increased the release of LDH and active oxygen (ROS) in L8824 cells, and led to the decrease of mitochondrial membrane potential (ΔΨm) and ATP content, the increase of mitochondrial ROS, the disorder of mitochondrial dynamics, and the initiation of Bcl-2/Bax-mediated apoptosis. Surprisingly, QU can alleviate the above PFOS-induced grass carp hepatocyte toxicity. In addition, in order to further explore the protective mechanism of QU, we used the molecular docking to predict the binding site between QU and AMPK, and found that there was a high binding capacity between QU and AMPK. In addition, we used Compound C (CC) and 3-Methyladenine (3-MA) to intervene. The results showed that CC and 3-MA intervention aggravated mitochondrial dysfunction and apoptosis factor expression in the QU+PFOS group. These data indicate that PFOS induces oxidative stress, mitochondrial dysfunction, and apoptosis. The regulation of AMPK/mTOR mediated mitophagy by QU may be a new therapeutic strategy to alleviate the hepatotoxicity of PFOS grass carp. This study provides theoretical basis and reference for exploring the toxic mechanism and biological toxic effects of PFOS, and provides a scheme for improving the economic benefits of aquaculture.

Mechanistic engineering of celastrol liposomes induces ferroptosis and apoptosis by directly targeting VDAC2 in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of most common and deadliest malignancies. Celastrol (Cel), a natural product derived from the Tripterygium wilfordii plant, has been extensively researched for its potential effectiveness in fighting cancer. However, its clinical application has been hindered by the unclear mechanism of action. Here, we used chemical proteomics to identify the direct targets of Cel and enhanced its targetability and anti-tumor capacity by developing a Cel-based liposomes in HCC. We demonstrated that Cel selectively targets the voltage-dependent anion channel 2 (VDAC2). Cel directly binds to the cysteine residues of VDAC2, and induces cytochrome C release via dysregulating VDAC2-mediated mitochondrial permeability transition pore (mPTP) function. We further found that Cel induces ROS-mediated ferroptosis and apoptosis in HCC cells. Moreover, coencapsulation of Cel into alkyl glucoside-modified liposomes (AGCL) improved its antitumor efficacy and minimized its side effects. AGCL has been shown to effectively suppress the proliferation of tumor cells. In a xenograft nude mice experiment, AGCL significantly inhibited tumor growth and promoted apoptosis. Our findings reveal that Cel directly targets VDAC2 to induce mitochondria-dependent cell death, while the Cel liposomes enhance its targetability and reduces side effects. Overall, Cel shows promise as a therapeutic agent for HCC.

Biotin decorated celastrol-loaded ZIF-8 nano-drug delivery system targeted epithelial ovarian cancer therapy

Ovarian cancer (OC) stands as the second most prominent factor leading to cancer-related fatalities, characterized by a notably low five-year survival rate. The insidious onset of OC combined with its resistance to chemotherapy poses significant challenges in terms of treatment, emphasizing the utmost importance of developing innovative therapeutic agents. Despite its remarkable anti-tumor efficacy, celastrol (CEL) faces challenges regarding its clinical utilization in OC due to its restricted water solubility and notable side effects. In this study, celastrol (CEL) was encapsulated into Zeolitic imidazolate framework-8(ZIF-8) nanoparticle and grafted with biotin-conjugated polyethylene glycol (CEL@ZIF-8@PEG-BIO). Comprehensive comparisons of the physicochemical properties and anticancer activities of CEL and CEL@ZIF-8@PEG-BIO were conducted. Our findings revealed that CEL@ZIF-8@PEG-BIO exhibited favorable characteristics, including hydrodynamic diameters of 234.5 nm, excellent water solubility, high drug loading (31.60% ± 2.85), encapsulation efficiency (60.52% ± 2.79), and minimal side effects. Furthermore, CEL@ZIF-8@PEG-BIO can release chemicals in response to an acidic micro-environment, which is more likely a tumor micro-environment. In vitro, studies showed that CEL@ZIF-8@BIO inhibited cell proliferation, led to mitochondrial membrane potential (MMP) decline, and generated reactive oxygen species in OC cells. Both in vitro and in vivo experiments indicated that CEL@ZIF-8@PEG-BIO enhanced anti-tumor activity against OC via up-regulated apoptosis-promoting biomarkers and rendered cancer cell apoptosis via the P38/JNK MAPK signaling pathway. In conclusion, we have successfully developed a novel drug delivery system (CEL@ZIF-8@PEG-BIO), resulting in significant improvements in both water solubility and anti-tumor efficacy thereby providing valuable insights for future clinical drug development.

Self-delivery of a metal-coordinated anti-angiogenic nanodrug with GSH depleting ability for synergistic chemo-phototherapy

Synergistic chemo-phototherapy has offered tremendous potential in cancer treatment. Nevertheless, nanosystems usually suffer from the complexity of multicomponents (polymeric or inorganic materials), which results in carrier-related toxicity issues. Moreover, the GSH over-expression of tumor cells seriously compromises ROS therapeutic efficiency. Herein, we designed a self-delivered nanodrug via Cu(II) coordination-driven co-self-assembly of celastrol (CST, a chemo-drug with anti-angiogenesis activity) and indocyanine green (ICG, a photosensitizer) for synergistic chemo-phototherapy with GSH depletion. The nanodrug was further cloaked by an erythrocyte membrane (RBC) to prolong the circulation time. Within the tumor microenvironment, the nanodrug would be disassembled upon intracellular GSH triggering. Moreover, the released Cu(II) could efficiently deplete the GSH, thus damaging the ROS-scavenging system and amplifying the phototherapeutic efficiency upon laser irradiation. The in vivo experiments validated the highly effective accumulation at tumor sites, potent tumor growth inhibition, and inappreciable systemic toxicity. The tumor microenvironment-responsive coordination-driven self-assembled biomimetic nanodrug may hold potential applications in tumor theranostics.

Regulation of Tumor Apoptosis of Poriae cutis-Derived Lanostane Triterpenes by AKT/PI3K and MAPK Signaling Pathways In Vitro

Poria cocos is traditionally used as both food and medicine. Triterpenoids in Poria cocos have a wide range of pharmacological activities, such as diuretic, sedative and tonic properties. In this study, the anti-tumor activities of poricoic acid A (PAA) and poricoic acid B (PAB), purified by high-speed counter-current chromatography, as well as their mechanisms and signaling pathways, were investigated using a HepG2 cell model. After treatment with PAA and PAB on HepG2 cells, the apoptosis was obviously increased (p < 0.05), and the cell cycle arrested in the G2/M phase. Studies showed that PAA and PAB can also inhibit the occurrence and development of tumor cells by stimulating the generation of ROS in tumor cells and inhibiting tumor migration and invasion. Combined Polymerase Chain Reaction and computer simulation of molecular docking were employed to explore the mechanism of tumor proliferation inhibition by PAA and PAB. By interfering with phosphatidylinositol-3-kinase/protein kinase B, Mitogen-activated protein kinases and p53 signaling pathways; and further affecting the expression of downstream caspases; matrix metalloproteinase family, cyclin-dependent kinase -cyclin, Intercellular adhesion molecules-1, Vascular Cell Adhesion Molecule-1 and Cyclooxygenase -2, may be responsible for their anti-tumor activity. Overall, the results suggested that PAA and PAB induced apoptosis, halted the cell cycle, and inhibited tumor migration and invasion through multi-pathway interactions, which may serve as a potential therapeutic agent against cancer.

The multifaceted nature of peroxiredoxins in chemical biology

Peroxiredoxins (Prx), thiol-dependent peroxidases, were first identified as H2O2 detoxifiers, and more recently as H2O2 sensors, intermediates in redox-signaling pathways, metabolism modulators, and chaperones. The multifaceted nature of Prx is not only dependent on their peroxidase activity but also strongly associated with specific protein-protein interactions that are being identified, and where the Prx oligomerization dynamics plays a role. Their oxidation by a peroxide substrate forms a sulfenic acid that opens a route to channel the redox signal to diverse protein targets. Recent research underscores the importance of different Prx isoforms in the cellular processes behind disease development with potential therapeutic applications.

Expression And Prognostic Role of PRDX1 In Gastrointestinal Cancers

Esophageal, gastric, liver, and colorectal cancers represent four prevalent gastrointestinal cancers that pose substantial threats to global health due to their high morbidity and mortality rates. Peroxiredoxin 1 (PRDX1), a significant component of the PRDXs family, primarily functions to counteract the peroxides produced by metabolic activities in the body, thereby maintaining the dynamic equilibrium of peroxides in vivo. Intriguingly, PRDX1 expression correlates strongly with cancer's onset, progression, and prognosis. This study mainly applied bioinformatics methods to analyze PRDX1's expression, diagnosis, and prognosis in gastrointestinal cancers and to summarize current research advancements. Evidence from the bioinformatics database suggested that the high expression of PRDX1 was a prominent characteristic of these four gastrointestinal cancers, with this observation reaching statistical significance. The high expression of PRDX1 in gastrointestinal cancer cells also confirms this result. Notably, the primary alteration in PRDX1 within these cancers is the presence of genetic mutations. PRDX1 demonstrated the highest diagnostic efficacy for colorectal cancer. Nevertheless, elevated PRDX1 levels only significantly diminished the survival time of liver cancer patients, exerting no statistically significant impact on the survival duration of patients afflicted by the other three types of gastrointestinal cancers. Recent research has indicated variability in PRDX1 expression across different cancer types, with high expression being predominantly observed in these four gastrointestinal cancers and, in most instances, unfavorable prognosis. These findings broadly align with the results derived from bioinformatics. This research underscores the high expression of PRDX1 in gastrointestinal cancers, its relevance to the diagnosis and prognosis monitoring of these cancers, and its potential to guide clinical treatment for these cancers.

Synthesis and Biological Evaluation of Novel 2-Amino-1,4-Naphthoquinone Amide-Oxime Derivatives as Potent IDO1/STAT3 Dual Inhibitors with Prospective Antitumor Effects

Indoleamine-2,3-dioxygenase 1 (IDO1) and signal transducer and activator of transcription 3 (STAT3) have emerged as significant targets in the tumor microenvironment for cancer therapy. In this study, we synthesized three novel 2-amino-1,4-naphthoquinone amide-oxime derivatives and identified them as dual inhibitors of IDO1 and STAT3. The representative compound NK3 demonstrated effective binding to IDO1 and exhibited good inhibitory activity (hIDO1 IC50 = 0.06 μM), leading to its selection for further investigation. The direct interactions between compound NK3 and IDO1 and STAT3 proteins were confirmed through surface plasmon resonance analysis. A molecular docking study of compound NK3 revealed key interactions between NK3 and IDO1, with the naphthoquinone-oxime moiety coordinating with the heme iron. In the in vitro anticancer assay, compound NK3 displayed potent antitumor activity against selected cancer cell lines and effectively suppressed nuclear translocation of STAT3. Moreover, in vivo assays conducted on CT26 tumor-bearing Balb/c mice and an athymic HepG2 xenograft model revealed that compound NK3 exhibited potent antitumor activity with low toxicity relative to 1-methyl-L-tryptophan (1-MT) and doxorubicin (DOX). Overall, these findings provided evidence that the dual inhibitors of IDO1 and STAT3 may offer a promising avenue for the development of highly effective drug candidates for cancer therapy.

Chimeric antigen receptor engineered natural killer cells for cancer therapy

Natural killer (NK) cells, a unique component of the innate immune system, are inherent killers of stressed and transformed cells. Based on their potent capacity to kill cancer cells and good tolerance of healthy cells, NK cells have been successfully employed in adoptive cell therapy to treat cancer patients. In recent years, the clinical success of chimeric antigen receptor (CAR)-T cells has proven the vast potential of gene-manipulated immune cells as the main force to fight cancer. Following the lessons learned from mature gene-transfer technologies and advanced strategies in CAR-T therapy, NK cells have been rapidly explored as a promising candidate for CAR-based therapy. An exponentially growing number of studies have employed multiple sources of CAR-NK cells to target a wide range of cancer-related antigens, showing remarkable outcomes and encouraging safety profiles. Clinical trials of CAR-NK cells have also shown their impressive therapeutic efficacy in the treatment of hematological tumors, but CAR-NK cell therapy for solid tumors is still in the initial stages. In this review, we present the favorable profile of NK cells as a potential platform for CAR-based engineering and then summarize the outcomes and strategies of CAR-NK therapies in up-to-date preclinical and clinical investigations. Finally, we evaluate the challenges remaining in CAR-NK therapy and describe existing strategies that can assist us in devising future prospective solutions.

Anticariogenic Activity of Celastrol and Its Enhancement of Streptococcal Antagonism in Multispecies Biofilm

Dental caries is a chronic disease resulting from dysbiosis in the oral microbiome. Antagonism of commensal Streptococcus sanguinis and Streptococcus gordonii against cariogenic Streptococcus mutans is pivotal to keep the microecological balance. However, concerns are growing on antimicrobial agents in anticaries therapy, for broad spectrum antimicrobials may have a profound impact on the oral microbial community, especially on commensals. Here, we report celastrol, extracted from Traditional Chinese Medicine's Tripterygium wilfordii (TW) plant, as a promising anticaries candidate. Our results revealed that celastrol showed antibacterial and antibiofilm activity against cariogenic bacteria S. mutans while exhibiting low cytotoxicity. By using a multispecies biofilm formed by S. mutans UA159, S. sanguinis SK36, and S. gordonii DL1, we observed that even at relatively low concentrations, celastrol reduced S. mutans proportion and thereby inhibited lactic acid production as well as water-insoluble glucan formation. We found that celastrol thwarted S. mutans outgrowth through the activation of pyruvate oxidase (SpxB) and H2O2-dependent antagonism between commensal oral streptococci and S. mutans. Our data reveal new anticaries properties of celastrol that enhance oral streptococcal antagonism, which thwarts S. mutans outgrowth, indicating its potential to maintain oral microbial balance for prospective anticaries therapy.

Ameliorative effects of mangiferin derivative TPX on insulin resistance via PI3K/AKT and AMPK signaling pathways in human HepG2 and HL-7702 hepatocytes

BACKGROUND

As a multifaceted metabolic disorder, insulin resistance is accompanied by the preceding onset of type 2 diabetes mellitus, hyperinsulinemia, metabolic dysfunction-associated fatty liver disease (MAFLD) and other metabolic syndromes. Currently, the number of existing drugs and mechanism-based strategies is limited to alleviate insulin resistance in clinics. As a natural polyphenol product derivative, 1,3,6,7-tetrapropylene acyloxy-ketone (TPX) showed a significant hypoglycemic effect in our previous studies. However, whether TPX could improve hepatic insulin sensitivity was unknown.

PURPOSE

To explore whether insulin sensitivity can be improved by the treatment with TPX and further investigate its mechanism(s) of activity.

METHODS

To mimic hyperglycemia and insulin resistance in vitro, human HepG2 and HL-7702 hepatocytes were exposed to high glucose. Cellular glucose uptake, glucose consumption, glycogen synthesis, and glucose production were quantified after TPX treatment. The effects of TPX on AMP-activated protein kinase (AMPK) phosphorylation, glucose metabolism, and insulin signal transduction were evaluated by western blotting and network pharmacology analysis. The eGFP-membrane of glucose transporter type 4 (GLUT4) lentivirus transfected cells were constructed to investigate the effects of TPX on GLUT4 mobilization. Reactive oxygen species activity in high glucose-induced insulin-resistant cells was measured by DCFH-DA to show oxidative stress.

RESULTS

Treatment with TPX improved glycogen synthesis and inhibited gluconeogenesis by regulating GSK3β, G6Pase, and PEPCK. Furthermore, high glucose-induced inhibition of glucose consumption, glucose uptake, and GLUT4-mediated membrane translocation were reverted by TPX. Accordingly, mechanistic investigations revealed that TPX interacted with AMPK protein and activated the phosphorylation of AKT, thereby improving energy homeostasis and further ameliorating hepatic insulin resistance. Network pharmacology analysis and molecular docking further confirmed AMPK as an active target of TPX. Concordantly, the pharmacological activity of TPX was reversed by the AMPK inhibitor compound C when hepatocytes were exposed to high glucose stimulation.

CONCLUSION

In summary, our study confirmed TPX contributions to insulin resistance improvements by targeting AMPK and PI3K/AKT to restore the insulin signaling pathway, which may be an important potential treatment strategy for insulin-resistance-related diseases, including MAFLD and diabetes.

Oxidative Stress Inducers in Cancer Therapy: Preclinical and Clinical Evidence

Reactive oxygen species (ROS) are metabolic byproducts that regulate various cellular processes. However, at high levels, ROS induce oxidative stress, which in turn can trigger cell death. Cancer cells alter the redox homeostasis to facilitate protumorigenic processes; however, this leaves them vulnerable to further increases in ROS levels. This paradox has been exploited as a cancer therapeutic strategy with the use of pro-oxidative drugs. Many chemotherapeutic drugs presently in clinical use, such as cisplatin and doxorubicin, induce ROS as one of their mechanisms of action. Further, various drugs, including phytochemicals and small molecules, that are presently being investigated in preclinical and clinical studies attribute their anticancer activity to ROS induction. Consistently, this review aims to highlight selected pro-oxidative drugs whose anticancer potential has been characterized with specific focus on phytochemicals, mechanisms of ROS induction, and anticancer effects downstream of ROS induction.

New insights into the roles of peroxiredoxins in cancer

Oxidative stress is one of the hallmarks of cancer. Tumorigenesis and progression are accompanied by elevated reactive oxygen species (ROS) levels and adaptive elevation of antioxidant expression levels. Peroxiredoxins (PRDXs) are among the most important antioxidants and are widely distributed in a variety of cancers. PRDXs are involved in the regulation of a variety of tumor cell phenotypes, such as invasion, migration, epithelial-mesenchymal transition (EMT) and stemness. PRDXs are also associated with tumor cell resistance to cell death, such as apoptosis and ferroptosis. In addition, PRDXs are involved in the transduction of hypoxic signals in the TME and in the regulation of the function of other cellular components of the TME, such as cancer-associated fibroblasts (CAFs), natural killer (NK) cells and macrophages. This implies that PRDXs are promising targets for cancer treatment. Of course, further studies are needed to realize the clinical application of targeting PRDXs. In this review, we highlight the role of PRDXs in cancer, summarizing the basic features of PRDXs, their association with tumorigenesis, their expression and function in cancer, and their relationship with cancer therapeutic resistance.