Norcantharidin: research advances in pharmaceutical activities and derivatives in recent years. Biomed Pharmacother. 2020;131:110755. [PMID: 33152920 DOI: 10.1016/j.biopha.2020.110755]

Nanoemulsion based lipid nanoparticles for effective demethylcantharidin delivery to cure liver cancer

Demethylcantharidin (DEM) is a widely used antitumor drug; however, its poor tumor targeting and serious organotoxicity limit its application. The aim of this study was to develop a new drug delivery system for efficient delivery of DEM. Nanoemulsion based lipid nanoparticles containing demethylcantharidin (DNLNs) were prepared by loading nanoemulsions into lipid nanoparticles. The cells proliferation, apoptosis, cycle, and uptake were investigated by Cell counting kit-8 (CCK-8), flow cytometry, and in situ fluorescence assays, respectively. Then, we established the H22 tumor-bearing mouse model to evaluate the antitumor efficacy of DNLNs and further studied its organ toxicity and distribution. DNLNs significantly inhibited the proliferation and promoted apoptosis of H22 cells, and H22 cells could take up more DNLNs. Compared with DEM, DNLNs had certain tumor-targeting properties, and the tumor inhibition rate increased by 23.24%. Moreover, DNLNs can increase white blood cell count and reduce organ toxicity. This study paves the way for nanoemulsion-based lipid nanoparticle (NLNs)-efficient DEM delivery to treat liver cancer.

Pentoxifylline and Norcantharidin Modify p62 Expression in 2D and 3D Cultures of B16F1 Cells

Three-dimensional cell cultures have improved the evaluation of drugs for cancer therapy, due to their high similarity to solid tumors. In melanoma, autophagy appears to show a dual role depending on the progression of the disease. p62 protein has been proposed for the evaluation of autophagic flux since its expression is an indicator of the state of autophagy. Pentoxifylline (PTX) and Norcantharidin (NCTD) are drugs that have been shown to possess anticancer effects. In this work, we used B16F1 mouse melanoma cells in two-dimensional (2D) monolayer cultures and three-dimensional (3D) spheroids to test the effect of PTX and NCTD over the p62 expression. We analyzed the effect on p62 expression through Western blot and immunofluorescence assays. Our results indicate that PTX decreases p62 expression in both cell culture models, while Norcantharidin increases its expression in 3D cultures at 24 h. Therefore, these drugs could have a potential therapeutic use for the regulation of autophagy in melanoma, depending on the state of evolution of the disease.

Dissecting the Puzzling Roles of FAM46C: A Multifaceted Pan-Cancer Tumour Suppressor with Increasing Clinical Relevance

FAM46C is a well-established tumour suppressor with a role that is not completely defined or universally accepted. Although FAM46C expression is down-modulated in several tumours, significant mutations in the FAM46C gene are only found in multiple myeloma (MM). Consequently, its tumour suppressor activity has primarily been studied in the MM context. However, emerging evidence suggests that FAM46C is involved also in other cancer types, namely colorectal, prostate and gastric cancer and squamous cell and hepatocellular carcinoma, where FAM46C expression was found to be significantly reduced in tumoural versus non-tumoural tissues and where FAM46C was shown to possess anti-proliferative properties. Accordingly, FAM46C was recently proposed to function as a pan-cancer prognostic marker, bringing FAM46C under the spotlight and attracting growing interest from the scientific community in the pathways modulated by FAM46C and in its mechanistic activity. Here, we will provide the first comprehensive review regarding FAM46C by covering (1) the intracellular pathways regulated by FAM46C, namely the MAPK/ERK, PI3K/AKT, β-catenin and TGF-β/SMAD pathways; (2) the models regarding its mode of action, specifically the poly(A) polymerase, intracellular trafficking modulator and inhibitor of centriole duplication models, focusing on connections and interdependencies; (3) the regulation of FAM46C expression in different environments by interferons, IL-4, TLR engagement or transcriptional modulators; and, lastly, (4) how FAM46C expression levels associate with increased/decreased tumour cell sensitivity to anticancer agents, such as bortezomib, dexamethasone, lenalidomide, pomalidomide, doxorubicin, melphalan, SK1-I, docetaxel and norcantharidin.

Norcantharidin Enhances the Antitumor Effect of 5-Fluorouracil by Inducing Apoptosis of Cervical Cancer Cells: Network Pharmacology, Molecular Docking, and Experimental Validation

The high recurrence rate of cervical cancer is a leading cause of cancer deaths in women. 5-Fluorouracil (5-FU) is an antitumor drug used to treat many types of cancer, but its diminishing effectiveness and side effects limit its use. Norcantharidin (NCTD), a demethylated derivative of cantharidin, exhibits various biological activities. Here, we investigated whether NCTD could potentiate 5-FU to induce cervical cancer cell death. To assess the cell viability and synergistic effects of the drugs, cell counting kit-8 and colony formation assays were performed using HR-HPV-positive cervical cancer cell lines. Annexin V-FITC/PI staining and TUNEL assays were performed to confirm the induction of apoptosis. The synergistic effect of NCTD on the antitumor activity of 5-FU was analyzed using network pharmacology, molecular docking, and molecular dynamics simulations. Apoptosis-related proteins were examined using immunoblotting. The combination of NCTD and 5-FU was synergistic in cervical cancer cell lines. Network pharmacological analysis identified 10 common targets of NCTD and 5-FU for cervical cancer treatment. Molecular docking showed the strong binding affinity of both compounds with CA12, CASP9, and PTGS1. Molecular dynamics simulations showed that the complex system of both drugs with caspase-9 could be in a stable state. NCTD enhanced 5-FU-mediated cytotoxicity by activating apoptosis-related proteins. NCTD acts synergistically with 5-FU to inhibit cervical cancer cell proliferation. NCTD enhances 5-FU-induced apoptosis in cervical cancer cell lines via the caspase-dependent pathway.

Mesenchymal stem cell-derived exosomes: Characteristics and applications in disease pathology and management

Mesenchymal stem cells (MSCs) possess a role in tissue regeneration and homeostasis because of inherent immunomodulatory capacity and the production of factors that encourage healing. There is substantial evidence that MSCs' therapeutic efficacy is primarily determined by their paracrine function including in cancers. Extracellular vesicles (EVs) are basic paracrine effectors of MSCs that reside in numerous bodily fluids and cell homogenates and play an important role in bidirectional communication. MSC-derived EVs (MSC-EVs) offer a wide range of potential therapeutic uses that exceed cell treatment, while maintaining protocell function and having less immunogenicity. We describe characteristics and isolation methods of MSC-EVs, and focus on their therapeutic potential describing its roles in tissue repair, anti-fibrosis, and cancer with an emphasis on the molecular mechanism and immune modulation and clinical trials. We also explain current understanding and challenges in the clinical applications of MSC-EVs as a cell free therapy.

Integrative approach using network pharmacology, bioinformatics, and experimental methods to explore the mechanism of cantharidin in treating colorectal cancer

Cantharidin, a terpenoid produced by blister beetles, has been used in traditional Chinese medicine to treat various ailments and cancers. However, its biological activity, impact, and anticancer mechanisms remain unclear. The Cantharidin chemical gene connections were identified using various databases. The GSE21815 dataset was used to collect the gene expression information. Differential gene analysis and gene ontology analyses were performed. Gene set enrichment analysis was used to assess the activation of disease pathways. Weighted gene co-expression network analysis and differential analysis were used to identify illness-associated genes, examine differential genes, and discover therapeutic targets via protein-protein interactions. MCODE analysis of major subgroup networks was used to identify critical genes influenced by Cantharidin, examine variations in the expression of key clustered genes in colorectal cancer vs. control samples, and describe the subject operators. Single-cell GSE188711 dataset was preprocessed to investigate Cantharidin's therapeutic targets and signaling pathways in colorectal cancer. Single-cell RNA sequencing was utilized to identify 22 cell clusters and marker genes for two different cell types in each cluster. The effects of different Cantharidin concentrations on colorectal cancer cells were studied in vitro. One hundred and ninety-seven Cantharidin-associated target genes and 480 critical genes implicated in the development of the illness were identified. Cantharidin significantly inhibited the proliferation and migration of HCT116 cells and promoted apoptosis at certain concentrations. Patients on current therapy develop inherent and acquired resistance. Our study suggests that Cantharidin may play an anti-CRC role by modulating immune function.

Bibliometric Analysis and Systemic Review of Cantharidin Research Worldwide

BACKGROUND

Cantharidin (CTD), a natural toxic compound from blister beetle Mylabris, has been used for cancer treatment for millenary. CTD and its analogs have become mainstream adjuvant drugs with radiotherapy and chemotherapy in clinical applications. However, the detailed pharmacology mechanism of CTD was not fully elucidated.

METHODS

Publications of CTD were collected from the Web of Science Core Collection database from 1991 to 2023 using CiteSpace, VOSviewer, and Scimago Graphica software.

RESULTS

A total of 1,611 publications of CTD were mainly published in China and the United States. The University of Newcastle has published the most researches. Mcclusey, Adam, Sakoff, Jennette, and Zhang, Yalin had the most CTD publications with higher H. Notably, CTD researches were mainly published in Bioorganic & Medicinal Chemistry Letters and the Journal of Biological Chemistry. Cluster profile results revealed that protein phosphatase 2A (PP2A), human gallbladder carcinoma, Aidi injection, and cell apoptosis were the hotspots. Concentration on the pharmacology function of PP2A subunit regulation, hepatotoxicity, nephrotoxicity, and cardiotoxicity mechanism should be strengthened in the future.

CONCLUSION

Bibliometric analysis combined with a systemic review of CTD research first revealed that PP2A and CTD analogs were the knowledge base of CTD, and PP2A subunit regulation and toxic mechanism could be the frontiers of CTD.

Cantharidin analogue alleviates dextran sulfate sodium-induced colitis in mice by inhibiting the activation of NF-κB signaling

Ulcerative colitis is a chronic inflammatory disease with a remitting-relapsing clinical course, it has evolved into a global burden given its high incidence worldwide. Cantharidin (CTD) derivatives are a class of compounds whose structures characterized with a 7-oxabicyclo [2.2.1]heptane core. Though potent cytotoxicity CTD and its derivatives showed, their clinical usage as anti-cancer drugs was limited by the toxicity in organs. In order to find new CTD analogues with good activity and lower toxicity, 21 CTD analogues with or without alkynyl substitution at C5 position of 7-oxabicyclo [2.2.1]heptane core were synthesized, some compounds showed better in vitro anti-inflammatory activity compared to CTD and norcantharidin (NCTD). Based on the structure-activity relationship results of in vitro experiment, analogue 3i was chosen for further study. Results from the acute toxicity in mice showed that 3i was hypotoxic with the single-dose MTD (maximum tolerated dose) for oral administration is over 1852 mg/kg, at least 35-fold lower than that of NCTD. Mechanism study indicated that 3i could potently inhibit TNF-α induced activation of NF-κB signaling by down-regulation the expression levels of phosphor- IKK, IκBα, and NF-κB p65, and alleviated dextran sulfate sodium-induced colitis in mice. This study indicated that CTD analogues with alkynyl substitution at C5 position of 7-oxabicyclo [2.2.1]heptane core is a kind of new compounds with good anti-inflammatory activity and lower toxicity in vivo, and might be used as therapeutic agents for inflammatory diseases.

Norcantharidin-Encapsulated C60-Modified Nanomicelles: A Potential Approach to Mitigate Cytotoxicity in Renal Cells and Simultaneously Enhance Anti-Tumor Activity in Hepatocellular Carcinoma Cells

OBJECTIVE

The objective of this study was to examine the preparation process of DSPE-PEG-C60/NCTD micelles and assess the impact of fullerenol (C60)-modified micelles on the nephrotoxicity and antitumor activity of NCTD.

METHOD

The micelles containing NCTD were prepared using the ultrasonic method and subsequently optimized and characterized. The cytotoxicity of micelles loaded with NCTD was assessed using the CCK-8 method on human hepatoma cell lines HepG2 and BEL-7402, as well as normal cell lines HK-2 and L02. Acridine orange/ethidium bromide (AO/EB) double staining and flow cytometry were employed to assess the impact of NCTD-loaded micelles on the apoptosis of the HK-2 cells and the HepG2 cells. Additionally, JC-1 fluorescence was utilized to quantify the alterations in mitochondrial membrane potential. The generation of reactive oxygen species (ROS) following micelle treatment was determined through 2',7'-dichlorofluorescein diacetate (DCFDA) staining.

RESULTS

The particle size distribution of the DSPE-PEG-C60/NCTD micelles was determined to be 91.57 nm (PDI = 0.231). The zeta potential of the micelles was found to be -13.8 mV. The encapsulation efficiency was measured to be 91.9%. The in vitro release behavior of the micelles followed the Higuchi equation. Cellular experiments demonstrated a notable decrease in the toxicity of the C60-modified micelles against the HK-2 cells, accompanied by an augmented inhibitory effect on cancer cells. Compared to the free NCTD group, the DSPE-PEG-C60 micelles exhibited a decreased apoptosis rate (12%) for the HK-2 cell line, lower than the apoptosis rate observed in the NCTD group (36%) at an NCTD concentration of 75 μM. The rate of apoptosis in the HepG2 cells exhibited a significant increase (49%), surpassing the apoptosis rate observed in the NCTD group (24%) at a concentration of 150 μM NCTD. The HK-2 cells exhibited a reduction in intracellular ROS and an increase in mitochondrial membrane potential (ΔψM) upon exposure to C60-modified micelles compared to the NCTD group.

CONCLUSIONS

The DSPE-PEG-C60/NCTD micelles, as prepared in this study, demonstrated the ability to decrease cytotoxicity and ROS levels in normal renal cells (HK-2) in vitro. Additionally, these micelles showed an enhanced antitumor activity against human hepatocellular carcinoma cells (HepG2, BEL-7402).

A metal ions-mediated natural small molecules carrier-free injectable hydrogel achieving laser-mediated photo-Fenton-like anticancer therapy by synergy apoptosis/cuproptosis/anti-inflammation

Tumor microenvironment (TME) plays an important role in the tumorigenesis, proliferation, invasion and metastasis. Thereby developing synergistic anticancer strategies with multiple mechanisms are urgent. Copper is widely used in the treatment of tumor chemodynamic therapy (CDT) due to its excellent laser-mediated photo-Fenton-like reaction. Additionally, copper can induce cell death through cuproptosis, which is a new modality different from the known death mechanisms and has great promise in tumor treatment. Herein, we report a natural small molecules carrier-free injectable hydrogel (NCTD Gel) consisted of Cu²⁺-mediated self-assembled glycyrrhizic acid (GA) and norcantharidin (NCTD), which are mainly governed by coordination and hydrogen bonds. Under 808 nm laser irradiation, NCTD Gel can produce reactive oxygen species (ROS), consume glutathione (GSH) and overcome hypoxia in TME, leading to synergistically regulate TME via apoptosis, cuproptosis and anti-inflammation. In addition, NCTD Gel's CDT display high selectivity and good biocompatibility as it relies on the weak acidity and H₂O₂ overexpression of TME. Notably, NCTD Gel's components are originated from clinical agents and its preparation process is easy, green and economical, without any excipients. This study provides a new carrier-free hydrogel synergistic antitumor strategy, which has a good prospect in industrial production and clinical transformation.

Tumor-Infiltrating iNKT Cells Activated through c-Kit/Sca-1 Are Induced by Pentoxifylline, Norcantharidin, and Their Mixtures for Killing Murine Melanoma Cells

The involvement of NK and other cytotoxic cells is considered the first defense line against cancer. However, a significant lack of information prevails on the possible roles played by factors considered characteristic of primitive cells, such as c-kit and Sca-1, in activating these cells, particularly in melanoma models subjected to treatments with substances under investigation, such as the case of norcantharidin. In this study, B16F1 murine melanoma cells were used to induce tumors in DBA/2 mice, estimating the proportions of NK and iNKT cells; the presence of activation (CD107a+) and primitive/activation (c-kit+/Lya6A+) markers and some tumor parameters, such as the presence of mitotic bodies, nuclear factor area, NK and iNKT cell infiltration in the tumor, infiltrated tumor area, and infiltrating lymphocyte count at 10x and 40x in specimens treated with pentoxifylline, norcantharidin, and the combination of both drugs. Possible correlations were estimated with Pearson's correlation analysis. It should be noted that, despite having demonstrated multiple correlations, immaturity/activation markers were related to these cells' activation. At the tumor site, iNKT cells are the ones that exert the cytotoxic potential on tumor cells, but they are confined to specific sites in the tumor. Due to the higher number of interactions of natural killer cells with tumor cells, it is concluded that the most effective treatment was PTX at 60 mg/kg + NCTD at 0.75 mg/kg.

Hepatotoxic mechanism of cantharidin: insights and strategies for therapeutic intervention

Cantharidin (CTD), a natural compound derived from Mylabris, is widely used in traditional Oriental medicine for its potent anticancer properties. However, its clinical application is restricted due to its high toxicity, particularly towards the liver. This review provides a concise understanding of the hepatotoxic mechanisms of CTD and highlights novel therapeutic strategies to mitigate its toxicity while enhancing its anticancer efficacy. We systematically explore the molecular mechanisms underlying CTD-induced hepatotoxicity, focusing on the involvement of apoptotic and autophagic processes in hepatocyte injury. We further discuss the endogenous and exogenous pathways implicated in CTD-induced liver damage and potential therapeutic targets. This review also summarizes the structural modifications of CTD derivatives and their impact on anticancer activity. Additionally, we delve into the advancements in nanoparticle-based drug delivery systems that hold promise in overcoming the limitations of CTD derivatives. By offering valuable insights into the hepatotoxic mechanisms of CTD and outlining potential avenues for future research, this review contributes to the ongoing efforts to develop safer and more effective CTD-based therapies.

Cantharidin suppresses hepatocellular carcinoma development by regulating EZH2/H3K27me3-dependent cell cycle progression and antitumour immune response

BACKGROUND

Cantharidin (CTD) is a major ingredient of cantharis (Mylabris phalerata Pallas) and has been used extensively in traditional Chinese medicines. It has been shown to exhibit anticancer activity in multiple types of cancer, especially hepatocellular carcinoma (HCC). However, there is no systematic study on the relationships among the regulatory networks of its targets in HCC therapy. We focused on histone epigenetic regulation and the influence of CTD on the immune response in HCC.

METHODS

We performed a comprehensive analysis of novel CTD targets in HCC based on network pharmacology and RNA-seq approaches. The mRNA levels of target genes were analyzed by qRT-PCR, and the corresponding protein levels were confirmed using enzyme-linked immunosorbent assay (ELISA) and immunohistochemical staining (IHC). ChIP-seq data were visualized by IGV software. The associations of gene transcript levels with the cancer immune score and infiltration level were investigated using TIMER. In vivo, the H22 mouse model of hepatocellular carcinoma was established by treatment with CTD and 5-Fu. The immune cell proportions in the blood were elevated in model mice, as shown by flow cytometry.

RESULTS

We identified 58 targets of CTD, which were involved in various pathways in cancer, including apoptosis, the cell cycle, EMT and immune pathways. Moreover, we found that 100 EMT-related genes were differentially expressed after CTD treatment in HCC cells. Interestingly, our results confirmed that the EZH2/H3K27me3 -related cell cycle pathway is a therapeutic target of CTD in antitumour. In addition, we evaluated the influence of CTD on the immune response. Our data showed that the significantly enriched gene sets were positively correlated with the chemokine biosynthetic and chemokine metabolic modules. The proportions of CD4+/CD8 + T cells and B cells were increased, but the proportion of Tregs was decreased after treatment with CTD in vivo. Moreover, we found that the expression of the inflammatory factor and immune checkpoint genes PD-1/PD-L1 was significantly reduced in the mouse model.

CONCLUSION

We performed a novel integrated analysis of the potential role of CTD in HCC treatment. Our results provide innovative insight into the mechanism by which cantharidin exerts antitumour effects by regulating target genes expression to mediate apoptosis, EMT, cell cycle progression and the immune response in HCC. Based on the effect of CTD on the immune response, it can be used as a potential effective drug to activate antitumour immunity for the treatment of liver cancer.

Efficacy of Aidi injection combined with chemotherapy, radiotherapy or chemoradiotherapy for unresectable esophageal cancer treatment: A meta-analysis and systematic review of 29 randomized controlled trials based on Asian populations (China)

OBJECTIVES

This study aimed to assess the efficacy of Aidi combined with standard treatment, including radiotherapy (R), chemotherapy (C), or chemoradiotherapy (CR), for unresectable esophageal cancer (EC).

METHODS

Eight online databases were queried to collect randomized controlled trials (RCTs) published from database construction to August 2022. Patients in the control group underwent standard treatment with R, C, or CR, whereas those in the experimental group underwent Aidi combined with standard treatment.

RESULTS

In this meta-analysis, 29 reports with 2079 patients were included. The results showed that the Aidi-based combination therapy groups had higher objective response rates (ORRs), disease control rates (DCRs), one-year overall survival (OS) and improvement and stability of Karnofsky performance status (KPS) than the control group (risk ratio (RR) = 1.24 (95% CI = 1.17-1.33), 1.09 (95% CI = 1.05-1.14), 1.50 (95% CI = 1.31-1.72), and 1.28 (95% CI = 1.16-1.41)). The Aidi-based combination therapy groups also had lower total incidence rates of bone marrow suppression (BMS), chemotherapy-induced nausea and vomiting (CINV) and radiation esophagitis (RE) than the control group (RR = 0.48 (95% CI = 0.41-0.56), 0.46 (95% CI = 0.36-0.58), and 0.49 (95% CI = 0.38-0.62)). In addition, subgroup analysis suggested that the optimal dose and cycle of Aidi injection combined therapy was 80-100 ml/time and 30 days/2 cycles. The efficacy of Aidi combined with DP (docetaxel + cisplatin) was better than the Aidi combined with PF (cisplatin plus fluorouracil).

CONCLUSION

Aidi-based combination therapy showed high efficacy for unresectable EC treatment and reduced the incidence rates of adverse events. However, further studies including higher-quality RCTs are needed to validate these findings.

TRIAL REGISTRATION NUMBER

INPLASY 202290020.

Supramolecular self-assembled AIE molecules are used in the search for target proteins in norcantharidin

Norcantharidin (NCTD), a demethylated derivative of cantharidin, is an anticancer active component in traditional Chinese medicine. At present, the main methods for finding its target proteins are pharmacological methods and biophysical screening, which cannot achieve the purpose of efficient and accurate screening. Here we established a new analytical method for specific fishing and assisted imaging for norcantharidin target proteins. For the AIE supramolecule probe, the benzophenone azide (BPA) fluorescent nanoparticles with strong AIE properties were encapsulated in biocompatible DSPE-PEG that covalently coupled with NCTD (named BPA@NCTD NPs). The target proteins of NCTD can be captured by BPA@NCTD NPs, and then be detected to investigate the potential signaling pathways. The screened differential proteins were analysed through the protein and signaling pathway database, and multiple signaling pathways were obtained and verified. The mechanism of norcantharidin in inhibiting the migration and invasion of A549 cells through the P53 signaling pathway was confirmed by Western blot experiments. Our research showed that AIE supramolecule probe BPA@NCTD NPs has the dual functions of specific screening of A549 cells target proteins and biological imaging, which not only offers a good anti-fluorescence quenching ability for the dynamic imaging process of NCTD, but also provides a novel and efficient specific method for efficient analysis of target proteins and signal pathways.

Role of exosomes in hepatocellular carcinoma and the regulation of traditional Chinese medicine

Hepatocellular carcinoma (HCC) usually occurs on the basis of chronic liver inflammatory diseases and cirrhosis. The liver microenvironment plays a vital role in the tumor initiation and progression. Exosomes, which are nanometer-sized membrane vesicles are secreted by a number of cell types. Exosomes carry multiple proteins, DNAs and various forms of RNA, and are mediators of cell-cell communication and regulate the tumor microenvironment. In the recent decade, many studies have demonstrated that exosomes are involved in the communication between HCC cells and the stromal cells, including endothelial cells, macrophages, hepatic stellate cells and the immune cells, and serve as a regulator in the tumor proliferation and metastasis, immune evasion and immunotherapy. In addition, exosomes can also be used for the diagnosis and treatment HCC. They can potentially serve as specific biomarkers for early diagnosis and drug delivery vehicles of HCC. Chinese herbal medicine, which is widely used in the prevention and treatment of HCC in China, may regulate the release of exosomes and exosomes-mediated intercellular communication. In this review, we summarized the latest progresses on the role of the exosomes in the initiation, progression and treatment of HCC and the potential value of Traditional Chinese medicine in exosomes-mediated biological behaviors of HCC.

Cantharidin and Its Analogue Norcantharidin Inhibit Metastasis-Inducing Genes S100A4 and MACC1

Colorectal cancer (CRC) is the third most prevalent and second deadliest cancer worldwide. In addition, metastasis directly causes up to 90% of all CRC deaths, highlighting the metastatic burden of the disease. Biomarkers such as S100A4 and MACC1 aid in identifying patients with a high risk of metastasis formation. High expression of S100A4 or MACC1 and to a greater extent the combination of both biomarkers is a predictor for metastasis and poor patient survival in CRC. MACC1 is a tumor-initiating and metastasis-promoting oncogene, whereas S100A4 has not been shown to initiate tumor formation but can, nevertheless, promote malignant tumor growth and metastasis formation. Cantharidin is a natural drug extracted from various blister beetle species, and its demethylated analogue norcantharidin has been shown in several studies to have an anti-cancer and anti-metastatic effect in different cancer entities such as CRC, breast cancer, and lung cancer. The impact of the natural compound cantharidin and norcantharidin on S100A4 and MACC1 gene expression, cancer cell migration, motility, and colony formation in vitro was tested. Here, for the first time, we have demonstrated that cantharidin and norcantharidin are transcriptional inhibitors of S100A4 and MACC1 mRNA expression, protein expression, and motility in CRC cells. Our results clearly indicate that cantharidin and, to a lesser extent, its analogue norcantharidin are promising compounds for efficient anti-metastatic therapy targeting the metastasis-inducing genes S100A4 and MACC1 for personalized medicine for cancer patients.

Norcantharidin toxicity profile: an in vivo murine study

Norcantharidin (NCTD) is the demethylated analog of cantharidin, with allegedly reduced toxicity. However, there is still limited information regarding its posology and potential risk in its use in cancer treatment. Healthy BDF1 mice were intraperitoneally administered with norcantharidin (0, 3, 6, 12, and 25 mg/kg) every 24 h for 6 days. Survivor mice were euthanized, and the brain, lungs, kidneys, spleen, and liver were procured for enzymatic and histopathological analysis in the liver and kidney. DL₅₀ were 8.86 mg/kg for females and 11.77 mg/kg for males. The treatments with 3.0 mg/kg and 6.0 mg/kg significantly modified the phosphorylase, alanine transaminase, and γ-glutamyl transferase activities; however, an organ-specific response was detected. A significant dose-dependent decrease was observed in the kidney for ROS, while the liver had the opposite effect. Histopathological analysis revealed a significant elevation in hepatocytes' nuclei average size and total area (3 mg/kg), as well as centrilobular vein and adjacent sinusoidal capillaries showed a significant difference. The portal triad presented a significant difference in veins and capillarity count in 6 mg/kg. Renal samples showed cortex convoluted tubules' average size significantly augmented in both doses' groups, and tubule count was found augmented in 6 mg/kg. These physiological effects of NCTD can be exploited as treatment strategies if able to operate in an established posology and proper testing.

New light on treatment of cervical cancer: Chinese medicine monomers can be effective for cervical cancer by inhibiting the PI3K/Akt signaling pathway

Cervical cancer (CC), as the most common malignant tumor of the female reproductive system, is infamous for its high morbidity and mortality rates. Its development and metastasis are intricate because numerous signaling pathways are involved. Since the cancer and the PI3K/Akt signaling pathway are closely intertwined, direct inhibition of either the PI3K/Akt pathway or its target genes and molecules may be remarkably constructive for treatment. Albeit remarkable advances in the treatment of CC, existing common anti-cancer medications are not without problems. These problems include myelotoxicity, cardiotoxicity, genotoxicity, and vasospasm, which are the most common and well-recognized toxicities associated with these medications. Therefore, it is necessary and urgent to develop novel, potent, secure, and more reasonably priced anticancer medications that are void of the above problems. Against this backdrop, Chinese medicine monomers have received more attention in recent years owing to their safety, low toxicity, few side effects, and anti-tumor properties. By regulating the PI3K/Akt signaling pathway, Chinese medicine monomers are effective not only in inhibiting CC growth, proliferation, apoptosis, invasion, migration, and reversing drug resistance but also in a variety of targets. Most previous earlier studies focused on the use of a single traditional Chinese medicine monomer to treat CC by regulating the PI3K/Akt signaling pathway rather than a combination of several such monomers. More importantly, to our knowledge, there has hardly been any study providing an exhaustive and comprehensive review of all the Chinese medicine monomers at CC. In response to this scarcity, we attempt in this paper to provide a comprehensive review of all the literature to date on traditional Chinese medicine monomers at cervical cancer, highlight the mechanisms and future prospects for their use in the prevention and treatment of cervical cancer.

Review targeted drug delivery systems for norcantharidin in cancer therapy

Norcantharidin (NCTD) is a demethylated derivative of cantharidin (CTD), the main anticancer active ingredient isolated from traditional Chinese medicine Mylabris. NCTD has been approved by the State Food and Drug Administration for the treatment of various solid tumors, especially liver cancer. Although NCTD greatly reduces the toxicity of CTD, there is still a certain degree of urinary toxicity and organ toxicity, and the poor solubility, short half-life, fast metabolism, as well as high venous irritation and weak tumor targeting ability limit its widespread application in the clinic. To reduce its toxicity and improve its efficacy, design of targeted drug delivery systems based on biomaterials and nanomaterials is one of the most feasible strategies. Therefore, this review focused on the studies of targeted drug delivery systems combined with NCTD in recent years, including passive and active targeted drug delivery systems, and physicochemical targeted drug delivery systems for improving drug bioavailability and enhancing its efficacy, as well as increasing drug targeting ability and reducing its adverse effects.

Graphical Abstract

Inhibition of MZF1/c-MYC Axis by Cantharidin Impairs Cell Proliferation in Glioblastoma

Myeloid zinc finger 1 (MZF1), also known as zinc finger protein 42, is a zinc finger transcription factor, belonging to the Krüppel-like family that has been implicated in several types of malignancies, including glioblastoma multiforme (GBM). MZF1 is reportedly an oncogenic gene that promotes tumor progression. Moreover, higher expression of MZF1 has been associated with a worse overall survival rate among patients with GBM. Thus, MZF1 may be a promising target for therapeutic interventions. Cantharidin (CTD) has been traditionally used in Chinese medicine to induce apoptosis and inhibit cancer cell proliferation; however, the mechanism by which CTD inhibits cell proliferation remains unclear. In this study, we found that the expression of MZF1 was higher in GBM tissues than in adjacent normal tissues and low-grade gliomas. Additionally, the patient-derived GBM cells and GBM cell lines presented higher levels of MZF1 than normal human astrocytes. We demonstrated that CTD had greater anti-proliferative effects on GBM than a derivative of CTD, norcantharidin (NCTD). MZF1 expression was strongly suppressed by CTD treatment. Furthermore, MZF1 enhanced the proliferation of GBM cells and upregulated the expression of c-MYC, whereas these effects were reversed by CTD treatment. The results of our study suggest that CTD may be a promising therapeutic agent for patients with GBM and suggest a promising direction for further investigation.

Norbornene and Related Structures as Scaffolds in the Search for New Cancer Treatments

The norbornene scaffold has arisen as a promising structure in medicinal chemistry due to its possible therapeutic application in cancer treatment. The development of norbornene-based derivatives as potential chemotherapeutic agents is attracting significant attention. Here, we report an unprecedented review on the recent advances of investigations into the antitumoral efficacy of different compounds, including the abovementioned bicyclic scaffold in their structure, in combination with chemotherapeutic agents or forming metal complexes. The impact that structural modifications to these bicyclic compounds have on the antitumoral properties and the mechanisms by which these norbornene derivatives act are discussed in this review. In addition, the use of norbornene, and its related compounds, encapsulation in nanosystems for its use in cancer therapies is here detailed.

Norcantharidin ameliorates estrogen deficient-mediated bone loss by attenuating the activation of extracellular signal-regulated kinase/ROS/NLRP3 inflammasome signaling

Osteoporosis, characterized by reduced bone mass, aberrant bone architecture, and elevated bone fragility, is driven by a disruption of bone homeostasis between bone resorption and bone formation. However, up to now, no drugs are perfect for osteoporosis treatment due to different defects. In this study, we demonstrated that norcantharidin (NCTD) could inhibit osteoclast formation and bone resorption by attenuating the ERK, ROS and NLRP3 inflammasomes pathways in vitro. Moreover, our in vivo study further confirms its preventive effects on estrogen-deficiency bone loss by inhibiting osteoclast formation and functions. Therefore, we could conclude that NCTD might be a potential candidates for the prevention and treatment of osteoporosis.

Mesenchymal stem cell-derived exosomes in cancer therapy resistance: recent advances and therapeutic potential

Mesenchymal stem cells (MSCs) are multipotent stromal cells that can be obtained from various human tissues and organs. They can differentiate into a wide range of cell types, including osteoblasts, adipocytes and chondrocytes, thus exhibiting great potential in regenerative medicine. Numerous studies have indicated that MSCs play critical roles in cancer biology. The crosstalk between tumour cells and MSCs has been found to regulate many tumour behaviours, such as proliferation, metastasis and epithelial-mesenchymal transition (EMT). Multiple lines of evidence have demonstrated that MSCs can secrete exosomes that can modulate the tumour microenvironment and play important roles in tumour development. Notably, very recent works have shown that mesenchymal stem cell-derived exosomes (MSC-derived exosomes) are critically involved in cancer resistance to chemotherapy agents, targeted-therapy drugs, radiotherapy and immunotherapy. In this review, we systematically summarized the emerging roles and detailed molecular mechanisms of MSC-derived exosomes in mediating cancer therapy resistance, thus providing novel insights into the clinical applications of MSC-derived exosomes in cancer management.

Illuminating the hepatotoxic mechanism of norcantharidin in rats using metabolomics analysis

Background

Norcantharidin (NCTD) has multiple antitumor effects. However, NCTD can induce significant hepatotoxicity and the mechanism of hepatotoxicity is not clear for now.

Objective

This study aimed to explore the hepatotoxicity of NCTD in rat by ultra-performance liquid chromatography (UPLC) quadrupole time-of-flight (Q-TOF)-MS (UPLC/Q-TOF-MS) metabolomics.

Results

Serum biochemical indices including alanine aminotransferase (ALT) and total bilirubin (T-BIL) were significantly increased. Histopathological and ultrastructure results revealed that hepatocytes were damaged. Furthermore, the metabolomics results showed that 11 metabolites in serum and 8 metabolites in liver were differential metabolites for NCTD hepatotoxicity. Four metabolic pathways including the sphingolipid metabolism, purine metabolism, arachidonic acid metabolism, and glycerophospholipid metabolism were the key metabolic pathways related to NCTD hepatotoxicity.

Conclusion

The metabolomics analysis in this study reveal new clues on the hepatotoxicity mechanism of NCTD in rats. These findings have potential applications in the toxicity study of NCTD.

Exosomes: A novel insight into traditional Chinese medicine

Exosomes are small extracellular vesicles and play an essential role in the mediation of intercellular communication both in health and disease. Traditional Chinese medicine (TCM) has historically been used to maintain human health and treat various diseases up till today. The interplay between exosomes and TCM has attracted researchers’ growing attention. By integrating the available evidence, TCM formulas and compounds isolated from TCM as exosome modulators have beneficial effects on multiple disorders, such as tumors, kidney diseases, and hepatic disease, which may associate with inhibiting cells proliferation, anti-inflammation, anti-oxidation, and attenuating fibrosis. Exosomes, a natural delivery system, are essential in delivering compounds isolated from TCM to target cells or tissues. Moreover, exosomes may be the potential biomarkers for TCM syndromes, providing strategies for TCM treatment. These findings may provide a novel insight into TCM from exosomes and serve as evidence for better understanding and development of TCM.

Norcantharidin induces ferroptosis via the suppression of NRF2/HO‑1 signaling in ovarian cancer cells

Increasing evidence has indicated a crucial role of ferroptosis in ovarian cancer (OC). Norcantharidin (NCTD), a normethyl compound of cantharidin, is extensively used in clinical practice as an optional anticancer drug. However, whether NCTD leads to ferroptosis in OC has not been previously explored, at least to the best of our knowledge. In the present study, the effect of NCTD on SKOV3 and OVCAR-3 cells was evaluated. The experimental data of the present study revealed that NCTD significantly suppressed SKOV3 and OVCAR-3 cell viability in a concentration- and time-dependent manner. The results of Cell Counting Kit-8 assay revealed that NCTD treatment decreased SKOV3 and OVCAR-3 cell viability. In comparison, pre-incubation with ferrostatin-1 (Fer-1) significantly reversed the NCTD-induced reduction in SKOV3 and OVCAR-3 cell viability; however, no changes in cell viability were observed when the SKOV3 and OVCAR-3 cells were treated with NCTD, in combination with the apoptosis inhibitor, Z-VAD-FMK, the ferroptosis inhibitor, necrostatin-1, and the autophagy inhibitor, 3-methyladenine. Additionally, it was observed that NCTD markedly enhanced reactive oxygen species production and malondialdehyde and ferrous ion levels in the SKOV3 and OVCAR-3 cells; however, pre-incubation with Fer-1 abolished these effects. Flow cytometry also demonstrated a significant increase in cell death following treatment of the SKOV3 and OVCAR-3 cells with NCTD; however, pre-incubation with Fer-1 also reversed these effects. In vivo experiments demonstrated that NCTD significantly reduced tumor volume and weight. More importantly, it was revealed that nuclear factor erythroid 2-related factor 2 (NRF2), heme oxygenase 1 (HO-1), glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (xCT) expression levels were significantly decreased following NCTD treatment. Collectively, NCTD may represent a potent anticancer agent in OC cells, and NCTD-induced ferroptotic cell death may be achieved by inhibiting the NRF2/HO-1/GPX4/xCT axis.

Norcantharidin Nanostructured Lipid Carrier (NCTD-NLC) Suppresses the Viability of Human Hepatocellular Carcinoma HepG2 Cells and Accelerates the Apoptosis

Malignant tumors have become the main cause of harm to human life and health. Development for new antitumor drugs and the exploration to drug carriers are becoming the concerned focus. In this study, we exploited our experiments to explore the effect of NCTD-NLC on liver cancer cells: the HepG2 cells cultured in vitro were given with NCTD-NLC administration; then, the estimation on cellular proliferation and apoptosis was accomplished through MTT and flow cytometry. Six hours after the administration, we performed the High Performance Liquid Chromatography (HPLC) detection to estimate the NCTD content in the heart, liver, spleen, lung, kidney and plasma of rats. Then, our outcomes showed that NCTD-NLC had a notable inhibitory effect on HepG2 cells, leading to a gradually decreased cellular viability. Cell viability was negatively correlated with NCTD-NLC concentration. Along with the concentration increasing, significantly increasing cellular apoptosis and gradually decreasing cellular viability were observed. The apoptosis rate was positively correlated with the concentration of NCTD-NLC. On the basis of the data we obtained, we found that the group with NCTD-NLC tail vein injection had an obvious advantage in drug delivery when compared with other groups. Through the tumorigenesis test to nude mice, we found that the tumor inhibition rate of the NCTD-NLC tail vein injection group had a 27.48% elevation in contrast to the NCTD gavage group, and it was also the group with the best tumor inhibition efficiency. In conclusion, the NCTD-NLC prepared in this study had a mighty inhibitory effect towards HepG2 cellular viability and an accelerating work on apoptosis. Tail vein injection of NCTD-NLC has the best drug delivery effect.

Two Zn(II) coordination polymers with anticancer drug norcantharidin as ligands for cancer chemotherapy

Here two Zn(II) coordination polymers [Zn₂₀(DMCA)₁₂]O₁₂ (DMCA = demethylcantharic acid, DMCA-Zn1) and [Zn(DMCA)](H₂O)₂ (DMCA-Zn2) are synthesized from a broad-spectrum anticancer drug norcantharidin (NCTD) and Zn(NO₃)₂·6H₂O under solvothermal conditions. By mechanical grinding with a biocompatible polymeric surfactant F127, ultrasonic treatment and filtration, DMCA-Zn1 and DMCA-Zn2 can be transformed into stable nanoparticles (DMCA-Zn1 NPs and DMCA-Zn2 NPs) suspended in water with average diameters of around 190 nm and 162 nm for drug delivery. The in vitro evaluation indicates that DMCA-Zn1 NPs and DMCA-Zn2 NPs can enter into HepG2 and Hep3B cancer cells via endocytosis and inhibit their proliferation. Meanwhile they exhibit relatively low toxicity to L927 normal cells. The in vivo evaluation confirms that DMCA-Zn1 NPs and DMCA-Zn2 NPs can more effectively inhibit the growth of Hep3B tumors with relatively few side effects compared with free NCTD. This approach can be extended to other anticancer drugs to construct nanodrug delivery systems for cancer treatment.

Norcantharidin Induces Immunogenic Cell Death of Bladder Cancer Cells through Promoting Autophagy in Acidic Culture

The acidic tumor microenvironment stands as a major obstacle to the efficient elimination of tumor cells. Norcantharidin (NCTD) is a powerful antitumor agent with multiple bioactivities. However, the effect of NCTD under acidic conditions is still unclear. Here, we report that NCTD can efficiently kill bladder cancer (BC) cells in acidic culture, and more intriguingly, NCTD can induce immunogenic cell death (ICD), thereby promoting antitumor immunity. In NCTD-treated BC cells, the surface-exposed calreticulin (ecto-CALR) was significantly increased. Consistently, co-culture with these cells promoted dendritic cell (DC) maturation. The NCTD-induced ICD is autophagy dependent, as autophagy inhibition completely blocked the NCTD-induced ecto-CALR and DC maturation. In addition, the DC showed a distinct maturation phenotype (CD80^high CD86^low) in acidic culture, as compared to that in physiological pH (CD⁸⁰ high CD86^high). Finally, the NCTD-induced ICD was validated in a mouse model. NCTD treatment significantly increased the tumor-infiltrating T lymphocytes in MB49 bladder cancer mice. Immunizing mice with NCTD-treated MB49 cells significantly increased tumor-free survival as compared to control. These findings demonstrate that NCTD could induce ICD in an acidic environment and suggest the feasibility to combine NCTD with anticancer immunotherapy to treat BC.

Long Non-coding RNA and mRNA Expression Change in Spinal Dorsal Horn After Exercise in Neuropathic Pain Rats

Exercise can help inhibition of neuropathic pain (NP), but the related mechanism remains being explored. In this research, we performed the effect of swimming exercise on the chronic constriction injury (CCI) rats. Compared with CCI group, the mechanical withdrawal threshold of rats in the CCI-Swim group significantly increased on the 21st and 28th day after CCI surgery. Second-generation RNA-sequencing technology was employed to investigate the transcriptomes of spinal dorsal horns in the Sham, CCI, and CCI-Swim groups. On the 28th day post-operation, 306 intersecting long non-coding RNAs (lncRNAs) and 173 intersecting mRNAs were observed between the CCI vs Sham group and CCI-Swim vs CCI groups. Then, the biological functions of lncRNAs and mRNAs in the spinal dorsal horn of CCI rats were then analyzed. Taking the results together, this study could provide a novel perspective for the treatment for NP.

Norcantharidin counteracts acquired everolimus resistance in renal cell carcinoma by dual inhibition of mammalian target of rapamycin complex 1 and complex 2 pathways in Vitro

Everolimus, an oral mammalian target of rapamycin complex 1 (mTORC1) inhibitor, presents a therapeutic option in metastatic renal cell carcinoma (RCC) patients who were intolerant to, or previously failed, immune- and vascular endothelial growth factor-targeted therapies. However, the onset of drug resistance limits its clinical use. One possible mechanism underpinning the resistance is that inhibiting mTORC1 by everolimus results in mTORC2-dependent activation of v-Akt murine thymoma viral oncogene (AKT) and upregulation of hypoxia-inducible transcription factors (HIF). Norcantharidin (NCTD) is a demethylated derivative of cantharidin with antitumor properties which is an active ingredient of the traditional Chinese medicine Mylabris. In this study, everolimus-resistant RCC cells (786-O-R) obtained by chronic everolimus treatment revealed higher level of HIF2α and over-activated mTORC2 pathway and NCTD inhibits cell proliferation in both everolimus-resistant and -sensitive RCC cells by arresting cell cycle in G0/G1 phase and reducing cell cycle-related proteins of C-Myc and cyclin D. Furthermore, NCTD shows synergistic anticancer effects combined with everolimus in everolimus-resistant 786-O-R cells. Mechanically, NCTD repressed both mTORC1 and mTORC2 signaling pathways as well as downstream molecular signaling pathways, such as p-4EBP1, p-AKT, HIF1α and HIF2α. Our findings provide sound evidence that combination of NCTD and everolimus is a potential therapeutic strategy for treating RCC and overcoming everolimus resistance by dual inhibition of mTORC1 and mTORC2.

Tumor-targeted hyaluronic acid-mPEG modified nanostructured lipid carriers for cantharidin delivery: An in vivo and in vitro study

AIM

Cantharidin (CTD), the major component of the anti-cancer medicine obtained from Mylabris cichorii, exerts good inhibitory effects on several cancers, such as liver and breast cancer. However, owing to its toxicity, its oral administration can cause various adverse effects, limiting its clinical applications. Therefore, the development of a novel nano-drug delivery system for CTD would be highly beneficial.

METHODS

A nanostructured lipid carrier (NLC) was designed to actively target CTD to tumor cells using a hyaluronic acid (HA)-decorated copolymer (mPEG-NH2); the NLCs were called HA-mPEG-CTD-NLC. HA-mPEG was synthesized using amidation, and HA-mPEG-CTD-NLC was generated through ultrasonic emulsification in water. The mean hydrodynamic diameter of the particles was approximately 119.3 nm.

RESULTS

Pharmacokinetic studies revealed that the half-life of HA-mPEG-CTD-NLC and its area under the curve were higher than those of a CTD solution. Further, the plasma clearance rate of HA-mPEG-CTD-NLC was 0.41 times that of the CTD solution, implying a significantly prolonged drug retention time in vivo. Fluorescence in vivo endo-microscopy and optical in vivo imaging revealed that HA-mPEG-CTD-NLC had superior cytotoxicity and targeting efficacy against SMMC-7721 cells. An evaluation of the in vivo anti-tumor activity showed that HA-mPEG-CTD-NLC significantly inhibited tumor growth and prolonged survival in tumor-bearing mice, with a tumor inhibition rate of 65.96%.

CONCLUSIONS

Our results indicate that HA-mPEG-CTD-NLC may have great potential in liver cancer-targeted therapy.

Metal-organic framework IRMOFs coated with a temperature-sensitive gel delivering norcantharidin to treat liver cancer

BACKGROUND

Norcantharidin (NCTD) is suitable for the treatment of primary liver cancer, especially early and middle primary liver cancer. This compound can reduce tumors and improve immune function. However, the side effects of NCTD have limited its application. There is a marked need to reduce the side effects and increase the efficacy of NCTD.

AIM

To develop a nanomaterial carrier, NCTD-loaded metal-organic framework IRMOF-3 coated with a temperature-sensitive gel (NCTD-IRMOF-3-Gel), aiming to improve the anticancer activity of NCTD and reduce the drug dose.

METHODS

NCTD-IRMOF-3-Gel was obtained by a coordination reaction. The apparent characteristics and in vitro release of NCTD-IRMOF-3-Gel were investigated. Cell cytotoxicity assays, flow cytometry, and apoptosis experiments in mouse hepatoma (Hepa1-6) cells were used to determine the anti-liver cancer activity of NCTD-IRMOF-3-Gel in in vitro models.

RESULTS

The particle size of NCTD-IRMOF-3-Gel was 50-100 nm, and the particle size distribution was uniform. The release curve showed that NCTD-IRMOF-3-Gel had an obvious sustained-release effect. The cytotoxicity assays showed that the free drug NCTD and NCTD-IRMOF-3-Gel treatments markedly inhibited Hepa1-6 cell proliferation, and the inhibition rate increased with increasing drug concentration. By flow cytometry, NCTD-IRMOF-3-Gel was observed to block the Hepa1-6 cell cycle in the S and G2/M phases, and the thermosensitive gel nanoparticles may inhibit cell proliferation by inducing cell cycle arrest. Apoptosis experiments showed that NCTD-IRMOF-3-Gel induced the apoptosis of Hepa1-6 cells.

CONCLUSION

Our results indicated that the NCTD-IRMOF-3-Gel may be beneficial for liver cancer disease treatment.

Strategies for Targeting Serine/Threonine Protein Phosphatases with Small Molecules in Cancer

Among numerous posttranslational regulation patterns, phosphorylation is reversibly controlled by the balance of kinases and phosphatases. The major form of cellular signaling involves the reversible phosphorylation of proteins on tyrosine, serine, or threonine residues. However, altered phosphorylation levels are found in diverse diseases, including cancer, making kinases and phosphatases ideal drug targets. In contrast to the success of prosperous kinase inhibitors, design of small molecules targeting phosphatase is struggling due to past bias and difficulty. This is especially true for serine/threonine phosphatases, one of the largest phosphatase families. From this perspective, we aim to provide insights into serine/threonine phosphatases and the small molecules targeting these proteins for drug development, especially in cancer. Through highlighting the modulation strategies, we aim to provide basic principles for the design of small molecules and future perspectives for the application of drugs targeting serine/threonine phosphatases.