Dihydroartemisinin induces pyroptosis by promoting the AIM2/caspase-3/DFNA5 axis in breast cancer cells

Metal-organic framework (MOF)-based materials for pyroptosis-mediated cancer therapy

Pyroptosis is regarded as a promising strategy to modulate tumor immune microenvironments for anticancer therapy. Although pyroptosis inducers have been extensively explored in the biomedical field, their drug resistance, off-targeting capacity, and adverse effects do not fulfill the growing demands of therapy. Nowadays, metal-organic frameworks (MOFs) with unique structures and facile synthesis/functionalization characteristics have shown great potential in anticancer therapy. The flexible choices of metal ions and ligands endow MOFs with inherent anti-cancer efficiency, whereas the porous structures in MOFs make them ideal vehicles for delivering various chemodrug-based pyroptosis inducers. In this review, we provide the latest advances in MOF-based materials to evoke pyroptosis and give a brief but comprehensive review of the different types of MOFs for pyroptosis-mediated cancer therapy. Finally, we also discuss the current challenges of MOF-based pyroptosis inducers and their future prospects in this field.

HDAC inhibitor regulates the tumor immune microenvironment via pyroptosis in triple negative breast cancer

Pyroptosis, an inflammatory form of cell death, promotes the release of immunogenic substances and stimulates immune cell recruitment, a process, which could turn cold tumors into hot ones. Thus, instigating pyroptosis in triple-negative breast cancer (TNBC) serves as a viable method for restoring antitumor immunity. We analyzed the effects of Histone Deacetylase Inhibitors (HDACi) on TNBC cells using the Cell Counting Kit-8 and colony formation assay. Apoptosis and lactate dehydrogenase (LDH) release assays were utilized to determine the form of cell death. The pyroptotic executor was validated by quantitative real-time polymerase chain reaction and western blot. Transcriptome was analyzed to investigate pyroptosis-inducing mechanisms. A subcutaneously transplanted tumor model was generated in BALB/c mice to evaluate infiltration of immune cells. HDACi significantly diminished cell proliferation, and pyroptotic "balloon"-like cells became apparent. HDACi led to an intra and extracellular material exchange, signified by the release of LDH and the uptake of propidium iodide. Among the gasdermin family, TNBC cells expressed maximum quantities of GSDME, and expression of GSDMA, GSDMB, and GSDME were augmented post HDACi treatment. Pyroptosis was instigated via the activation of the caspase 3-GSDME pathway with the potential mechanisms being cell cycle arrest and altered intracellular REDOX balance due to aberrant glutathione metabolism. In vivo experiments demonstrated that HDACi can activate pyroptosis, limit tumor growth, and escalate CD8+ lymphocyte and CD11b+ cell infiltration along with an increased presence of granzyme B in tumors. HDACi can instigate pyroptosis in TNBC, promoting infiltration of immune cells and consequently intensifying the efficacy of anticancer immunity.

Dihydroartemisinin is an inhibitor of trained immunity through Akt/mTOR/HIF1α signaling pathway

Trained immunity is mechanistically defined as the metabolically and epigenetically mediated long-term functional adaptation of the innate immune system, characterized by a heightened response to a secondary stimulation. Given appropriate activation, trained immunity represents an attractive anti-infective therapeutic target. Nevertheless, excessive immune response and subsequent inflammatory cascades may contribute to pathological tissue damage, indicating that the negative impacts of trained immunity appear to be significant. In this study, we show that innate immune responses such as the production of extracellular traps, pro-inflammatory cytokines, and autophagy-related proteins were markedly augmented in trained BMDMs. Furthermore, heat-killed C. albicans priming promotes the activation of the AIM2 inflammasome, and AIM2-/- mice exhibit impaired memory response induced by heat-killed C. albicans. Therefore, we establish that the AIM2 inflammasome is involved in trained immunity and emerges as a promising therapeutic target for potentially deleterious effects. Dihydroartemisinin can inhibit the memory response induced by heat-killed C. albicans through modulation of mTOR signaling and the AIM2 inflammasome. The findings suggest that dihydroartemisinin can reduce the induction of trained immunity by heat-killed C. albicans in C57BL/6 mice. Dihydroartemisinin is one such therapeutic intervention that has the potential to treat of diseases characterized by excessive trained immunity.

Role of non-coding RNAs mediated pyroptosis on cancer therapy: a review

INTRODUCTION

Non-coding RNAs (ncRNAs), which are incapable of encoding proteins, are involved in the progression of numerous tumors by altering transcriptional and post-transcriptional processing. Recent studies have revealed prominent features of ncRNAs in pyroptosis, a type of non-apoptotic programmed cellular destruction linked to an inflammatory reaction. Drug resistance has arisen gradually as a result of anti-apoptotic proteins, therefore strategies based on pyroptotic cell death have attracted increasing attention. We have observed that ncRNAs may exert significant influence on cancer therapy, chemotherapy, radio- therapy, targeted therapy and immunotherapy, by regulating pyroptosis.

AREAS COVERED

Literatures were searched (December 2023) for studies on cancer therapy for ncRNAs-mediated pyroptotic cell death.

EXPERT OPINION

The most universal mechanical strategy for ncRNAs to regulate target genes is competitive endogenous RNAs (ceRNA). Besides, certain ncRNAs could directly interact with proteins and modulate downstream genes to induce pyroptosis, resulting in tumor growth or inhibition. In this review, we aim to display that ncRNAs, predominantly long non-coding RNAs (lncRNAs), microRNAs (miRNAs) and circular RNAs (circRNAs), could function as potential biomarkers for diagnosis and prognosis and produce new insights into anti-cancer strategies modulated by pyroptosis for clinical applications.

Revitalizing antitumor immunity: Leveraging nucleic acid sensors as therapeutic targets

Nucleic acid sensors play a critical role in recognizing and responding to pathogenic nucleic acids as danger signals. Upon activation, these sensors initiate downstream signaling cascades that lead to the production and release of pro-inflammatory cytokines, chemokines, and type I interferons. These immune mediators orchestrate diverse effector responses, including the activation of immune cells and the modulation of the tumor microenvironment. However, careful consideration must be given to balancing the activation of nucleic acid sensors to avoid unwanted autoimmune or inflammatory responses. In this review, we provide an overview of nucleic acid sensors and their role in combating cancer through the perception of various aberrant nucleic acids and activation of the immune system. We discuss the connections between different programmed cell death modes and nucleic acid sensors. Finally, we outline the development of nucleic acid sensor agonists, highlighting how their potential as therapeutic targets opens up new avenues for cancer immunotherapy.

Crosstalk between metabolism and cell death in tumorigenesis

It is generally recognized that tumor cells proliferate more rapidly than normal cells. Due to such an abnormally rapid proliferation rate, cancer cells constantly encounter the limits of insufficient oxygen and nutrient supplies. To satisfy their growth needs and resist adverse environmental events, tumor cells modify the metabolic pathways to produce both extra energies and substances required for rapid growth. Realizing the metabolic characters special for tumor cells will be helpful for eliminating them during therapy. Cell death is a hot topic of long-term study and targeting cell death is one of the most effective ways to repress tumor growth. Many studies have successfully demonstrated that metabolism is inextricably linked to cell death of cancer cells. Here we summarize the recently identified metabolic characters that specifically impact on different types of cell deaths and discuss their roles in tumorigenesis.

Regulation of Dihydroartemisinin on the pathological progression of laryngeal carcinoma through the periostin/YAP/IL-6 pathway

Objective

Laryngeal cancer (LC) is one of the most common squamous cell carcinomas of the head and neck in clinical practice, and its incidence has been increasing in recent years, but the prognosis of the patients is not favorable. Hence, it is critical to re-understand and deeply study the causes and mechanisms of LC and explore new effective treatment methods and strategies. In this study, we analyzed the effect of Dihydroartemisinin (DHA) on the pathological progression of LC through the periostin (POSTN)/Yes-associated protein (YAP)/interleukin (IL)-6 pathway, which can provide new clinical references and guidelines.

Methods

POSTN, YAP, and IL-6 levels in 18 pairs of fresh LC tissues and adjacent counterparts in our hospital were detected. Additionally, LC TU686 cell line was purchased for DHA treatment of various concentrations to detect changes in cell biological behavior. Finally, we built a tumor-bearing mouse model with C57BL/6 mice and intragastrically administrated DHA to the animals to observe the growth of living tumors and to measure POSTN, YAP, and IL-6 expression in tumor tissues.

Results

As indicated by PCR, Western blotting, and immunohistochemistry, POSTN, YAP, and IL-6 presented higher expression in LC tissues than in adjacent counterparts. In cell experiments, the cloning rate of LC cells decreased and the apoptosis rate increased after DHA intervention, with 160 μmol/L DHA contributing to the most significant effect on LC activity inhibition. Furthermore, DHA-intervened cells exhibited markedly reduced POSTN, YAP, and IL-6 levels. Finally, the tumorigenesis experiment in nude mice showed inhibited tumor growth after DHA administration. And consistently, the expressions of POSTN, YAP, and IL-6 in living tumors decreased.

Conclusions

DHA can inhibit POSTN/YAP/IL-6 transduction, accelerate LC cell apoptosis, and alleviate the malignant progression of LC.

New prospects of cancer therapy based on pyroptosis and pyroptosis inducers

Pyroptosis is a gasdermin-mediated programmed cell death (PCD) pathway. It differs from apoptosis because of the secretion of inflammatory molecules. Pyroptosis is closely associated with various malignant tumors. Recent studies have demonstrated that pyroptosis can either inhibit or promote the development of malignant tumors, depending on the cell type (immune or cancer cells) and duration and severity of the process. This review summarizes the molecular mechanisms of pyroptosis, its relationship with malignancies, and focuses on current pyroptosis inducers and their significance in cancer treatment. The molecules involved in the pyroptosis signaling pathway could serve as therapeutic targets for the development of novel drugs for cancer therapy. In addition, we analyzed the potential of combining pyroptosis with conventional anticancer techniques as a promising strategy for cancer treatment.

Pyroptosis in cancer treatment and prevention: the role of natural products and their bioactive compounds

Targeting programmed cell death (PCD) has been emerging as a promising therapeutic strategy in cancer. Pyroptosis, as a type of PCDs, leads to the cleavage of the gasdermin family and the secretion of pro-inflammatory factors. Gasdermin D (GSDMD) and gasdermin E (GSDME) are the two main executors of pyroptosis. Pyroptosis in tumor and immune cells is essential for tumor progression. Natural products, especially Chinese medicinal herb and their bioactive compounds have recently been regarded as anti-tumor agents that regulate cell pyroptosis under different circumstances. Here, we review the underlying mechanisms of natural products that activate pyroptosis in tumor cells and inhibit pyroptosis in immune cells. Pyroptosis activation in tumor cells leads to tumor cell death, yet pyroptosis inhibition in immune cells may prevent tumor occurrence. Elucidation of the signaling pathways involved in pyroptosis contributes to the understanding of the anti-tumor role of natural products and their potential clinical applications. Therefore, we outline a promising strategy for cancer therapy and prevention using natural products via modulation of pyroptosis.

Echinacoside regulates PI3K/AKT/HIF-1α/VEGF cross signaling axis in proliferation and apoptosis of breast cancer

CONTEXT

Echinacoside (ECH) is a natural anti-cancer compound and is of great value in cancer treatment. However, the mechanism underlying this effect on breast cancer (BC) was unclear.

OBJECTIVE

To explore the mechanism of ECH treating BC by network pharmacology and experimental validation.

MATERIALS & METHODS

Several databases were searched to screen potential targets of ECH and obtain information on targets related to BC. STRING was applied to construct a Protein-protein interaction (PPI) network. DAVID was applied for Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Gene Expression Profiling Interactive Analysis (GEPIA) was searched for the relationship between the expression profile and overall survival of major targets in normal breast and BC tissues. Finally, the results of network pharmacology analysis were validated by experiments.

RESULTS

Seventeen targets of ECH overlapped with targets in BC. Ten hub targets were determined through PPI. By GO and KEGG analysis 15 entries and 25 pathways were obtained, in which phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), hypoxia inducible factor-1 (HIF-1) and vascular endothelial growth factor (VEGF) played greater roles. Validation of key targets in the GEPIA database showed that PIK3R1 and PIK3CD remained consistent with the results of the study. Experiments in vitro showed ECH inhibited proliferation, induced apoptosis and reduced mRNA levels and protein expression of PI3K, AKT, hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor A (VEGFA) in MCF-7 cells. Furthermore, experiments in vivo revealed that ECH significantly reduced tumor growth, promoted apoptosis and decreased the related mRNA levels and protein expression, suggesting ECH works on BC by regulating PI3K/AKT/HIF-1α/VEGF signaling pathway.

DISCUSSION & CONCLUSION

In summary, ECH played an important role in anti-BC by regulating PI3K/AKT/HIF-1α/VEGF signaling pathway. Furthermore, ECH had multi-target and multi-pathway effects, which may be a promising natural compound for treating BC.

AIM2 fosters lung adenocarcinoma immune escape by modulating PD-L1 expression in tumor-associated macrophages via JAK/STAT3

This work was devised to discuss the effect of AIM2 on the immunosuppression of LUAD tumors, as well as its molecular mechanism. An allograft mouse model was built. Mouse macrophages were isolated and collected. The infiltration level of Mø and expression of M1 Mø, M2 Mø markers, and PD-L1 were assayed by IHC and flow cytometry. Expression levels of M1 Mø and M2 Mø marker genes and PD-L1 were detected by qPCR. The expression of proteins linked with JAK/STAT3 was tested by western blot. CD8+T cells and NK cells were activated in vitro and co-cultured with mouse macrophages, and their cytotoxicity was detected by LDH method. The proportion of CD206+PD-L1+ cells and the activation and proliferation of CD8+T cells were assayed by flow cytometry. Multicolor immunofluorescence was utilized to assay the co-localization of proteins. AIM2 demonstrated a high expression in LUAD, exhibiting a conspicuous positive correlation with the expression of the M2 Mø markers as well as PD-L1. Expression of M1 markers was upregulated after knockdown of AIM2, while M2 markers expression and PD-L1 were downregulated, and the colocalization of proteins linked with PD-L1 and M2 Mø was decreased. The infiltration and cytotoxicity of CD8+T cells and NK cells increased after silencing AIM2. After the knockdown of AIM2, which was enriched in the JAK/STAT3 pathway, the phosphorylation levels of JAK1, JAK2, and STAT3 were reduced, the immune infiltration level of CD8+T cells increased, and the co-localization level of PD-L1 and PD-1 dropped. The activity and proliferation level of CD8+T cells were increased with the reduced PD-1 expression. AIM2 fosters M2 Mø polarization and PD-L1 expression via the JAK/STAT3 pathway. Moreover, AIM2 promotes the immune escape of LUAD via the PD-1/PD-L1 axis. Our work may blaze a trail for the clinical treatment of LUAD.

Recent advances in caspase-3, breast cancer, and traditional Chinese medicine: a review

Caspases (cysteinyl aspartate-specific proteinases) are a group of structurally similar proteases in the cytoplasm that can be involved in cell differentiation, programmed death, proliferation, and inflammatory generation. Experts have found that caspase-3 can serve as a terminal splicing enzyme in apoptosis and participate in the mechanism by which cytotoxic drugs kill cancer cells. Breast cancer (BC) has become the most common cancer among women worldwide, posing a severe threat to their lives. Finding new therapeutic targets for BC is the primary task of contemporary physicians. Numerous studies have revealed the close association between caspase-3 expression and BC. Caspase-3 is essential in BC's occurrence, invasion, and metastasis. In addition, Caspase-3 exerts anticancer effects by regulating cell death mechanisms. Traditional Chinese medicine acting through caspase-3 expression is increasingly used in clinical treatment. This review summarizes the biological mechanism of caspase-3 and research progress on BC. It introduces a variety of traditional Chinese medicine related to caspase-3 to provide new ideas for the clinical treatment of BC.

Pyroptosis: shedding light on the mechanisms and links with cancers

Pyroptosis, a novel form of programmed cell death (PCD) discovered after apoptosis and necrosis, is characterized by cell swelling, cytomembrane perforation and lysis, chromatin DNA fragmentation, and the release of intracellular proinflammatory contents, such as Interleukin (IL) 8, IL-1β, ATP, IL-1α, and high mobility group box 1 (HMGB1). Our understanding of pyroptosis has increased over time with an increase in research on the subject: gasdermin-mediated lytic PCD usually, but not always, requires cleavage by caspases. Moreover, new evidence suggests that pyroptosis induction in tumor cells results in a strong inflammatory response and significant cancer regression, which has stimulated great interest among scientists for its potential application in clinical cancer therapy. It's worth noting that the side effects of chemotherapy and radiotherapy can be triggered by pyroptosis. Thus, the intelligent use of pyroptosis, the double-edged sword for tumors, will enable us to understand the genesis and development of cancers and provide potential methods to develop novel anticancer drugs based on pyroptosis. Hence, in this review, we systematically summarize the molecular mechanisms of pyroptosis and provide the latest available evidence supporting the antitumor properties of pyroptosis, and provide a summary of the various antitumor medicines targeting pyroptosis signaling pathways.

Recent advances in natural compounds inducing non-apoptotic cell death for anticancer drug resistance

The induction of cell death is recognized as a potent strategy for cancer treatment. Apoptosis is an extensively studied form of cell death, and multiple anticancer drugs exert their therapeutic effects by inducing it. Nonetheless, apoptosis evasion is a hallmark of cancer, rendering cancer cells resistant to chemotherapy drugs. Consequently, there is a growing interest in exploring novel non-apoptotic forms of cell death, such as ferroptosis, necroptosis, pyroptosis, and paraptosis. Natural compounds with anticancer properties have garnered significant attention due to their advantages, including a reduced risk of drug resistance. Over the past two decades, numerous natural compounds have been discovered to exert anticancer and anti-resistance effects by triggering these four non-apoptotic cell death mechanisms. This review primarily focuses on these four non-apoptotic cell death mechanisms and their recent advancements in overcoming drug resistance in cancer treatment. Meanwhile, it highlights the role of natural compounds in effectively addressing cancer drug resistance through the induction of these forms of non-apoptotic cell death.

Dihydroartemisinin ameliorates the liver steatosis in metabolic associated fatty liver disease mice by attenuating the inflammation and oxidative stress and promoting autophagy

PURPOSE

To explore the effect and potential mechanism of dihydroartemisinin (DHA) on metabolism-related fatty liver disease.

METHODS

A metabolic associated fatty liver disease (MAFLD) mice model was induced with continuous supplies of high-fat diet. DHA was intraperitoneally injected into mice. The weight of mice was monitored. The concentrations of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) in serum were detected by an automatic biochemical analyzer. The liver tissues were stained by hematoxylin and eosin and oil red O. The level of inflammation, oxidative stress, and autophagy was assessed by reverse transcription polymerase chain reaction, biochemical examination, Western blot and transmission electron microscope assays.

RESULTS

DHA treatment reduced theMAFLD-enhanced the level of weight gain, the concentrations of TC, TG, LDL and malonaldehyde, while increasedthe MAFLD-decreased the concentrations of HDL and superoxide dismutase. DHA ameliorated the MAFLD-aggravated pathological changes and the number of lipid droplets. Low dose of DHA declined the MAFLD-induced the enhancement of the expression of inflammatory factor. DHA treatment increased the MAFLD-enhanced the level of autophagy related protein, while decreased the MAFLD-reduced the protein level of p62. The increased level of autophagy was confirmed by transmission electron microscope.

CONCLUSIONS

DHA can improve liver steatosis in MAFLD mice by inhibiting inflammation and oxidative stress and promoting autophagy.

The crosstalk between ferroptosis and anti-tumor immunity in the tumor microenvironment: molecular mechanisms and therapeutic controversy

The advent of immunotherapy has significantly reshaped the landscape of cancer treatment, greatly enhancing therapeutic outcomes for multiple types of cancer. However, only a small subset of individuals respond to it, underscoring the urgent need for new methods to improve its response rate. Ferroptosis, a recently discovered form of programmed cell death, has emerged as a promising approach for anti-tumor therapy, with targeting ferroptosis to kill tumors seen as a potentially effective strategy. Numerous studies suggest that inducing ferroptosis can synergistically enhance the effects of immunotherapy, paving the way for a promising combined treatment method in the future. Nevertheless, recent research has raised concerns about the potential negative impacts on anti-tumor immunity as a consequence of inducing ferroptosis, leading to conflicting views within the scientific community about the interplay between ferroptosis and anti-tumor immunity, thereby underscoring the necessity of a comprehensive review of the existing literature on this relationship. Previous reviews on ferroptosis have touched on related content, many focusing primarily on the promoting role of ferroptosis on anti-tumor immunity while overlooking recent evidence on the inhibitory effects of ferroptosis on immunity. Others have concentrated solely on discussing related content either from the perspective of cancer cells and ferroptosis or from immune cells and ferroptosis. Given that both cancer cells and immune cells exist in the tumor microenvironment, a one-sided discussion cannot comprehensively summarize this topic. Therefore, from the perspectives of both tumor cells and tumor-infiltrating immune cells, we systematically summarize the current conflicting views on the interplay between ferroptosis and anti-tumor immunity, intending to provide potential explanations and identify the work needed to establish a translational basis for combined ferroptosis-targeted therapy and immunotherapy in treating tumors.

Pyroptosis and inflammasomes in cancer and inflammation

Nonprogrammed cell death (NPCD) and programmed cell death (PCD) are two types of cell death. Cell death is significantly linked to tumor development, medication resistance, cancer recurrence, and metastatic dissemination. Therefore, a comprehensive understanding of cell death is essential for the treatment of cancer. Pyroptosis is a kind of PCD distinct from autophagy and apoptosis in terms of the structure and function of cells. The defining features of pyroptosis include the release of an inflammatory cascade reaction and the expulsion of lysosomes, inflammatory mediators, and other cellular substances from within the cell. Additionally, it displays variations in osmotic pressure both within and outside the cell. Pyroptosis, as evidenced by a growing body of research, is critical for controlling the development of inflammatory diseases and cancer. In this paper, we reviewed the current level of knowledge on the mechanism of pyroptosis and inflammasomes and their connection to cancer and inflammatory diseases. This article presents a theoretical framework for investigating the potential of therapeutic targets in cancer and inflammatory diseases, overcoming medication resistance, establishing nanomedicines associated with pyroptosis, and developing risk prediction models in refractory cancer. Given the link between pyroptosis and the emergence of cancer and inflammatory diseases, pyroptosis-targeted treatments may be a cutting-edge treatment strategy.

The role of novel programmed cell death in head and neck squamous cell carcinoma: from mechanisms to potential therapies

Head and neck squamous cell carcinoma (HNSCC) is a common oral cancer with poor prognosis and for which no targeted therapeutic strategies are currently available. Accumulating evidence has demonstrated that programmed cell death (PCD) is essential in the development of HNSCC as a second messenger. PCD can be categorized into numerous different subroutines: in addition to the two well-known types of apoptosis and autophagy, novel forms of programmed cell death (e.g., necroptosis, pyroptosis, ferroptosis, and NETosis) also serve as key alternatives in tumorigenesis. Cancer cells are not able to avoid all types of cell death simultaneously, since different cell death subroutines follow different regulatory pathways. Herein, we summarize the roles of novel programmed cell death in tumorigenesis and present our interpretations of the molecular mechanisms with a view to the development of further potential therapies.

Effect of tumor-associated macrophages on the pyroptosis of breast cancer tumor cells

Macrophages are immune cells with high plasticity that are widely distributed in all tissues and organs of the body. Under the influence of the immune microenvironment of breast tumors, macrophages differentiate into various germline lineages. They exert pro-tumor or tumor-suppressive effects by secreting various cytokines. Pyroptosis is mediated by Gasdermin family proteins, which form holes in cell membranes and cause a violent inflammatory response and cell death. This is an important way for the body to fight off infections. Tumor cell pyroptosis can activate anti-tumor immunity and inhibit tumor growth. At the same time, it releases inflammatory mediators and recruits tumor-associated macrophages (TAMs) for accumulation. Macrophages act as "mediators" of cytokine interactions and indirectly influence the pyroptosis pathway. This paper describes the mechanism of action on the part of TAM in affecting the pyroptosis process of breast tumor cells, as well as its key role in the tumor microenvironment. Additionally, it provides the basis for in-depth research on how to use immune cells to affect breast tumors and guide anti-tumor trends, with important implications for the prevention and treatment of breast tumors. Video Abstract.

Pyroptosis Modulators: New Insights of Gasdermins in Health and Disease

Pyroptosis is an inflammation-dependent type of cell death that has been in the spotlight for the scientific community in the last few years. Crucial players in the process of pyroptosis are the members of the gasdermin family of proteins, which have been parallelly studied. Upon induction of pyroptosis, gasdermins suffer from structural changes leading to the formation of pores in the membrane that subsequently cause the release of pro-inflammatory contents. Recently, it has been discovered that oxidation plays a key role in the activation of certain gasdermins. Here, we review the current knowledge on pyroptosis and human gasdermins, focusing on the description of the different members of the family, their molecular structures, and their influence on health and disease directly or non-directly related to inflammation. Noteworthy, we have focused on the existing understanding of the role of this family of proteins in cancer, which could translate into novel promising strategies aimed at benefiting human health. In conclusion, the modulation of pyroptosis and gasdermins by natural and synthetic compounds through different mechanisms, including modification of the redox state of cells, has been proven effective and sets precedents for future therapeutic strategies.

The PANoptosis-related signature indicates the prognosis and tumor immune infiltration features of gliomas

Background

Gliomas are the most common primary tumors of the central nervous system, with high heterogeneity and highly variable survival rates. Accurate classification and prognostic assessment are key to the selection of treatment strategies. One hallmark of the tumor is resistance to cell death. PANoptosis, a novel mode of programmed cell death, has been frequently reported to be involved in the innate immunity associated with pathogen infection and played an important role in cancers. However, the intrinsic association of PANoptosis with glioma requires deeper investigation.

Methods

The genetics and expression of the 17 reported PANoptosome-related genes were analyzed in glioma. Based on these genes, patients were divided into two subtypes by consensus clustering analysis. After obtaining the differentially expressed genes between clusters, a prognostic model called PANopotic score was constructed after univariate Cox regression, LASSO regression, and multivariate Cox regression. The expression of the 5 genes included in the PANopotic score was also examined by qPCR in our cohort. The prognostic differences, clinical features, TME infiltration status, and immune characteristics between PANoptotic clusters and score groups were compared, some of which even extended to pan-cancer levels.

Results

Gene mutations, CNVs and altered gene expression of PANoptosome-related genes exist in gliomas. Two PANoptotic clusters were significantly different in prognosis, clinical features, immune characteristics, and mutation landscapes. The 5 genes included in the PANopotic score had significantly altered expression in glioma samples in our cohort. The high PANoptotic score group was inclined to show an unfavorable prognosis, lower tumor purity, worse molecular genetic signature, and distinct immune characteristics related to immunotherapy. The PANoptotic score was considered as an independent prognostic factor for glioma and showed superior prognostic assessment efficacy over several reported models. PANopotic score was included in the nomogram constructed for the potential clinical prognostic application. The associations of PANoptotic score with prognostic assessment and tumor immune characteristics were also reflected at the pan-cancer level.

Conclusion

Molecular subtypes of glioma based on PANoptosome-related genes were proposed and PANoptotic score was constructed with different clinical characteristics of anti-tumor immunity. The potential intrinsic association between PANoptosis and glioma subtypes, prognosis, and immunotherapy was revealed.

Molecular insights into artemisinin resistance in Plasmodium falciparum: An updated review

Malaria still poses a major burden on human health around the world, especially in endemic areas. Plasmodium resistance to several antimalarial drugs has been one of the major hindrances in control of malaria. Thus, the World Health Organization recommended artemisinin-based combination therapy (ACT) as a front-line treatment for malaria. The emergence of parasites resistant to artemisinin, along with resistant to ACT partner drugs, has led to ACT treatment failure. The artemisinin resistance is mostly related to the mutations in the propeller domain of the kelch13 (k13) gene that encodes protein Kelch13 (K13). The K13 protein has an important role in parasite reaction to oxidative stress. The most widely spread mutation in K13, with the highest degree of resistance, is a C580Y mutation. Other mutations, which are already identified as markers of artemisinin resistance, are R539T, I543T, and Y493H. The objective of this review is to provide current molecular insights into artemisinin resistance in Plasmodium falciparum. The trending use of artemisinin beyond its antimalarial effect is described. Immediate challenges and future research directions are discussed. Better understanding of the molecular mechanisms underlying artemisinin resistance will accelerate implementation of scientific findings to solve problems with malarial infection.

Progress in the study of molecular mechanisms of cell pyroptosis in tumor therapy

Pyroptosis, also known as cellular inflammatory necrosis, is a programmed cell death mediated by the Gasdermin family of proteins. The mechanisms by which pyroptosis occurs are divided into the GSDMD-mediated Caspase-1 and Caspase-4/-5/-11-dependent classical inflammatory vesicle pathway and the GSDME-mediated Caspase-3 and granzyme-dependent non-classical inflammatory vesicle pathways, among others. Recent studies have shown that pyroptosis has both inhibitory and promotive effects on tumor development. Pyroptosis induction also plays a dual role in antitumor immunotherapy: on the one hand, it suppresses antitumor immunity by promoting the release of inflammatory factors, and on the other hand, it inhibits tumor cell proliferation by triggering antitumor inflammatory responses. In addition, cell scorching plays an essential role in chemotherapy. It has been found that natural drugs modulating the induction of cell scorch are necessary to treat tumors. Therefore, studying the specific mechanisms of cell pyroptosis in different tumors can provide more ideas for developing oncology drugs. In this paper, we review the molecular mechanisms of pyroptosis and the role of pyroptosis in tumor development and treatment to provide new targets for clinical tumor treatment, prognosis, and antitumor drug development.

A novel pharmacological mechanism of anti-cancer drugs that induce pyroptosis

Pyroptosis is an inflammasome-induced lytic form of programmed cell death, and its main effect involves the release of inflammatory mediators when a cell dies, resulting in an inflammatory response in the body. The key to pyroptosis is the cleavage of GSDMD or other gasdermin families. Some drugs can cause cleavage GSDMD or other gasdermin members cause pyroptosis and suppress cancer growth and development. This review explores several drugs that may induce pyroptosis, thereby contributing to tumor treatment. Pyroptosis-inducing drugs, such as arsenic, platinum, and doxorubicin, were used originally in cancer treatment. Other pyroptosis-inducing drugs, such as metformin, dihydroartemisinin, and famotidine, were used to control blood glucose, treat malaria, and regulate blood lipid levels and are effective tumor treatments. By summarizing drug mechanisms, we provide a valuable basis for treating cancers by inducing pyroptosis. In future, the use of these drugs may contribute to new clinical treatments.

Targeting pyroptosis in breast cancer: biological functions and therapeutic potentials on It

Pyroptosis is a lytic and inflammatory type of programmed cell death that is mediated by Gasdermin proteins (GSDMs). Attractively, recent evidence indicates that pyroptosis involves in the development of tumors and can serve as a new strategy for cancer treatment. Here, we present a basic knowledge of pyroptosis, and an overview of the expression patterns and roles of GSDMs in breast cancer. In addition, we further summarize the available evidence of pyroptosis in breast cancer progression and give insight into the clinical potential of applying pyroptosis in anticancer strategies for breast cancer. This review will deepen our understanding of the relationship between pyroptosis and breast cancer, and provide a novel potential therapeutic avenue for breast cancer.

Zinc Protoporphyrin-9 Potentiates the Anticancer Activity of Dihydroartemisinin

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

Targeted Pyroptosis Is a Potential Therapeutic Strategy for Cancer

As a type of regulated cell death (RCD) mode, pyroptosis plays an important role in several kinds of cancers. Pyroptosis is induced by different stimuli, whose pathways are divided into the canonical pathway and the noncanonical pathway depending on the formation of the inflammasomes. The canonical pathway is triggered by the assembly of inflammasomes, and the activation of caspase-1 and then the cleavage of effector protein gasdermin D (GSDMD) are promoted. While in the noncanonical pathway, the caspase-4/5/11 (caspase 4/5 in humans and caspase 11 in mice) directly cleave GSDMD without the assembly of inflammasomes. Pyroptosis is involved in various cancers, such as lung cancer, gastric cancer, hepatic carcinoma, breast cancer, and colorectal carcinoma. Pyroptosis in gastric cancer, hepatic carcinoma, breast cancer, and colorectal carcinoma is related to the canonical pathway, while both the canonical and noncanonical pathway participate in lung cancer. Moreover, simvastatin, metformin, and curcumin have effect on these cancers and simultaneously promote the pyroptosis of cancer cells. Accordingly, pyroptosis may be an important therapeutic target for cancer.

The role of cuproptosis-related gene in the classification and prognosis of melanoma

Background

Melanoma, as one of the most aggressive and malignant cancers, ranks first in the lethality rate of skin cancers. Cuproptosis has been shown to paly a role in tumorigenesis, However, the role of cuproptosis in melanoma metastasis are not clear. Studying the correlation beteen the molecular subtypes of cuproptosis-related genes (CRGs) and metastasis of melanoma may provide some guidance for the prognosis of melanoma.

Methods

We collected 1085 melanoma samples in The Cancer Genome Atlas(TCGA) and Gene Expression Omnibus(GEO) databases, constructed CRGs molecular subtypes and gene subtypes according to clinical characteristics, and investigated the role of CRGs in melanoma metastasis. We randomly divide the samples into train set and validation set according to the ratio of 1:1. A prognostic model was constructed using data from the train set and then validated on the validation set. We performed tumor microenvironment analysis and drug sensitivity analyses for high and low risk groups based on the outcome of the prognostic model risk score. Finally, we established a metastatic model of melanoma.

Results

According to the expression levels of 12 cuproptosis-related genes, we obtained three subtypes of A₁, B₁, and C₁. Among them, C₁ subtype had the best survival outcome. Based on the differentially expressed genes shared by A₁, B₁, and C₁ genotypes, we obtained the results of three gene subtypes of A₂, B₂, and C₂. Among them, the B₂ group had the best survival outcome. Then, we constructed a prognostic model consisting of 6 key variable genes, which could more accurately predict the 1-, 3-, and 5-year overall survival rates of melanoma patients. Besides, 98 drugs were screened out. Finally, we explored the role of cuproptosis-related genes in melanoma metastasis and established a metastasis model using seven key genes.

Conclusions

In conclusion, CRGs play a role in the metastasis and prognosis of melanoma, and also provide new insights into the underlying pathogenesis of melanoma.

NLRP3-mediated pyroptosis in diabetic nephropathy

Diabetic nephropathy (DN) is the main cause of end-stage renal disease (ESRD), which is characterized by a series of abnormal changes such as glomerulosclerosis, podocyte loss, renal tubular atrophy and excessive deposition of extracellular matrix. Simultaneously, the occurrence of inflammatory reaction can promote the aggravation of DN-induced kidney injury. The most important processes in the canonical inflammasome pathway are inflammasome activation and membrane pore formation mediated by gasdermin family. Converging studies shows that pyroptosis can occur in renal intrinsic cells and participate in the development of DN, and its activation mechanism involves a variety of signaling pathways. Meanwhile, the activation of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome can not only lead to the occurrence of inflammatory response, but also induce pyroptosis. In addition, a number of drugs targeting pyroptosis-associated proteins have been shown to have potential for treating DN. Consequently, the pathogenesis of pyroptosis and several possible activation pathways of NLRP3 inflammasome were reviewed, and the potential drugs used to treat pyroptosis in DN were summarized in this review. Although relevant studies are still not thorough and comprehensive, these findings still have certain reference value for the understanding, treatment and prognosis of DN.

A pyroptosis-associated gene risk model for predicting the prognosis of triple-negative breast cancer

BACKGROUND

Pyroptosis is a novel identified form of inflammatory cell death that is important in the development and progression of various diseases, including malignancies. However, the relationship between pyroptosis and triple-negative breast cancer (TNBC) is still unclear. Therefore, we started to investigate the potential prognostic value of pyroptosis-associated genes in TNBC.

METHODS

Thirty-three genes associated with pyroptosis were extracted from previous publications, 30 of which were identified in the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) cohort. On the basis of the 30 pyroptosis-related genes, patients with TNBC were divided into three subtypes through unsupervised cluster analysis. The prognostic value of each pyroptosis-associated gene was assessed, and six genes were selected by univariate and LASSO Cox regression analysis to establish a multigene signature. According to the median value of risk score, patients with TNBC in the training and validation cohorts were separated to high- and low-risk sets. The enrichment analysis was conducted on the differentially expressed genes (DEGs) of the two risk sets using R clusterProfiler package. Moreover, the ESTIMATE score and immune cell infiltration were calculated by the ESTIMATE and CIBERSORT methods. After that, the correlation among pyroptosis-associated risk score and the expression of immune checkpoint-associated genes as well as anti-cancer drugs sensitivities were further analyzed.

RESULTS

In the training and validation cohorts, patients with TNBC in the high-risk set were found in a lower survival rate than those in the low-risk set. Combined with the clinical characteristics, the pyroptosis-related risk score was identified as an independent risk factor for the prognosis of patients with TNBC. The enrichment analysis indicated that the DEGs between the two risk groups were mainly enriched by immune responses and activities. In addition, patients with TNBC in the low-risk set were found to have a higher value of ESTIMATE score and a higher rate of immune cell infiltration. Finally, the expression levels of five genes [programmed cell death protein 1 (PD-1); cytotoxic t-lymphocyte antigen-4 (CTLA4); lymphocyte activation gene 3 (LAG3); T cell immunoreceptor with Ig and ITIM domains (TIGIT)] associated with immune checkpoint inhibitors were identified to be higher in the low-risk sets. The sensitivities of some anti-cancer drugs commonly used in breast cancer were found closely related to the pyroptosis-associated risk model.

CONCLUSION

The pyproptosis-associated risk model plays a vital role in the tumor immunity of TNBC and can be applied to be a prognostic predictor of patients with TNBC. Our discovery will provide novel insight for TNBC immunotherapies.

Potential roles and molecular mechanisms of phytochemicals against cancer

Increasing evidence has been reported regarding phytochemicals, plant secondary metabolites, having therapeutic functions against numerous human diseases. Recently, phytochemicals (flavonoids, polyphenols, terpenoids, alkaloids, saponins, coumarins and so on) have shown promising anti-cancer efficacy with their distinct advantages of high efficiency and low toxicity. They regulate programmed cell death (apoptosis, pyroptosis, and autophagy), migration and senescence-related signaling pathways of cancer via the modulation of reactive oxygen species (ROS), mitogen activated protein kinase (MAPK) pathway, deleted in liver cancer 1 (DLC1), nuclear factor κ light-chain-enhancer of activated B cell (NF-κB) pathways and glycolytic enzymes. Here, we review the molecular mechanisms by which phytochemicals prevent the development of cancer. Furthermore, phytochemicals combined with chemotherapeutic agents could target the crosstalk among multiple signal cascades to block chemoresistance and attenuate carcinogenic properties, and can be considered as a novel and potential therapeutic strategy. Our review highlights that the mechanisms and promising applications are required to be understood to decisively establish the anti-cancer efficacy of natural phytochemicals.

The role of pyroptosis and its crosstalk with immune therapy in breast cancer

Pyroptosis is a brand-new category of programmed cell death (PCD) that is brought on by multitudinous inflammasomes, which can recognize several stimuli to pilot the cleavage of and activate inflammatory cytokines like IL-18 and IL-1β is believed to have dual effects on the development of multiple cancers including breast cancer. However, pyroptosis has different effects on cancers depending on the type of tissues and their distinct heredity. Recently, the association between pyroptosis and breast cancer has received more and more attention, and it is thought that inducing pyroptosis could be used as a cancer treatment option. In addition, a great deal of evidence accumulating over the past decades has evinced the crosstalk between pyroptosis and tumor immunological therapy. Thus, a comprehensive summary combining the function of pyroptosis in breast cancer and antitumor immunity is imperative. We portray the prevalent knowledge of the multidimensional roles of pyroptosis in cancer and summarize the pyroptosis in breast cancer principally. Moreover, we elucidate the influence of inflammasomes and pyroptosis-produced cytokines on the tumor microenvironment (TME) of breast cancer. Taken together, we aim to provide a clue to harness pyroptosis rationally and apply it to augment immunotherapy efficiency for breast cancer.

Regulated cell death (RCD) in cancer: key pathways and targeted therapies

Regulated cell death (RCD), also well-known as programmed cell death (PCD), refers to the form of cell death that can be regulated by a variety of biomacromolecules, which is distinctive from accidental cell death (ACD). Accumulating evidence has revealed that RCD subroutines are the key features of tumorigenesis, which may ultimately lead to the establishment of different potential therapeutic strategies. Hitherto, targeting the subroutines of RCD with pharmacological small-molecule compounds has been emerging as a promising therapeutic avenue, which has rapidly progressed in many types of human cancers. Thus, in this review, we focus on summarizing not only the key apoptotic and autophagy-dependent cell death signaling pathways, but the crucial pathways of other RCD subroutines, including necroptosis, pyroptosis, ferroptosis, parthanatos, entosis, NETosis and lysosome-dependent cell death (LCD) in cancer. Moreover, we further discuss the current situation of several small-molecule compounds targeting the different RCD subroutines to improve cancer treatment, such as single-target, dual or multiple-target small-molecule compounds, drug combinations, and some new emerging therapeutic strategies that would together shed new light on future directions to attack cancer cell vulnerabilities with small-molecule drugs targeting RCD for therapeutic purposes.

BI 2536 induces gasdermin E-dependent pyroptosis in ovarian cancer

Background

The frequent emergence of drug resistance to chemotherapy is a major obstacle for the treatment of ovarian cancer. There is a need for novel drugs to fulfill this challenge. Pyroptosis-inducing drugs can inhibit tumor growth. However, their roles in ovarian cancer have not been demonstrated.

Methods

We tested the effectiveness of a novel drug, BI 2536, which we found in colorectal cancer. Cell proliferation, cell cycle, and drug-induced apoptosis and pyroptosis were tested. In vivo treatments were performed using a cell-derived xenograft model.

Results

BI 2536 significantly inhibited the proliferation of ovarian cancer cells and induced cell cycle arrest at the G2/M phases. After BI 2536 treatment, DNA fragmentation and PS exposure on the outside of apoptotic cells were detected. Moreover, the pyroptotic phenotype of ovarian cancer cells along with the release of LDH and HMGB1 were observed, indicating the leakage of cells. Western blot analysis verified that BI 2536 induced GSDME-mediated pyroptosis. Pyroptosis was abolished after additional treatment with Z-DEVD-FMK, a caspase-3 inhibitor. Thus, BI 2536 induced pyroptosis in ovarian cancer through the caspase-3/GSDME pathway. In vivo experiments further demonstrated the antitumoral effect and ability of BI 2536 to accumulate CD8⁺ T cells in ovarian cancer.

Conclusion

In this study, we identified BI 2536 as an effective anti-ovarian cancer drug that inhibits proliferation, arrests the cell cycle, induces apoptosis and pyroptosis, and leads to the accumulation of CD8⁺ T cells in tumor sites. Drug-induced pyroptosis may have promising prospects for reducing side effects and activating immune responses.

Genomic analysis quantifies pyroptosis in the immune microenvironment of HBV-related hepatocellular carcinoma

Pyroptosis, a way of pro-inflammatory death, plays a significant part in the tumor microenvironment (TME). A recent study has shown that the hepatitis C virus changes the TME by inducing pyroptosis against hepatocellular carcinoma (HCC). However, compared to TME in hepatitis C virus-infected HCC, the exploration of immune characteristics and response to immunotherapy associated with the pyroptosis phenotype is still insufficient in hepatitis B virus-related HCC (HBV-HCC). Our study constructed pyroptosis-score (PYS) via principal-component analysis (PCA) to unveil the link between pyroptosis and tumor immunity in 369 HBV-HCC patients. Compared with the low-PYS group, subjects with higher PYS were associated with poor prognosis but were more susceptible to anti-PD-L1 treatment. In addition, we found that PYS can serve independently as a prognostic factor for HBV-HCC, making it possible for us to identify specific small molecule drugs with a potential value in inhibiting tumors via targeting pyroptosis. Also, the target genes predicted by the Weighted gene co-expression network analysis (WGCNA) and pharmacophore model were enriched in the HIF-1 signaling pathway and NF-kB transcription factor activity, which were related to the mechanism of inflammation-driven cancer. The PYS is extremely important in predicting prognosis and responses to immunotherapy. New treatment strategies for inflammation-driven cancers may be found by targeting pyroptosis.

Emerging mechanisms of pyroptosis and its therapeutic strategy in cancer

Pyroptosis, a type of inflammatory programmed cell death, is triggered by caspase cleavage of gasdermin family proteins. Based on accumulating evidence, pyroptosis is closely associated with tumour development, but the molecular mechanism underlying pyroptosis activation and the signalling pathways regulated by pyroptosis remain unclear. In this review, we first briefly introduce the definition, morphological characteristics, and activation pathways of pyroptosis and the effect of pyroptosis on anticancer immunity. Then we review recent progress concerning the complex role of pyroptosis in various tumours. Importantly, we summarise various FDA-approved chemotherapy drugs or natural compounds that exerted antitumor properties by inducing pyroptosis of cancer cells. Moreover, we also focus on the current application of nanotechnology-induced pyroptosis in tumour therapy. In addition, some unsolved problems and potential future research directions are also raised.

Gasdermin E: A Prospective Target for Therapy of Diseases

Gasdermin E (GSDME) is a member of the gasdermin protein family, which mediates programmed cell death including apoptosis and pyroptosis. Recently, it was suggested that GSDME is activated by chemotherapeutic drugs to stimulate pyroptosis of cancer cells and trigger anti-tumor immunity, which is identified as a tumor suppressor. However, GSDME-mediated pyroptosis contributes to normal tissue damage, leading to pathological inflammations. Inhibiting GSDME-mediated pyroptosis might be a potential target in ameliorating inflammatory diseases. Therefore, targeting GSDME is a promising option for the treatment of diseases in the future. In this review, we introduce the roles of GSDME-driven programmed cell death in different diseases and the potential targeted therapies of GSDME, so as to provide a foundation for future research.

Artemisinin-Type Drugs in Tumor Cell Death: Mechanisms, Combination Treatment with Biologics and Nanoparticle Delivery

Artemisinin, the most famous anti-malaria drug initially extracted from Artemisia annua L., also exhibits anti-tumor properties in vivo and in vitro. To improve its solubility and bioavailability, multiple derivatives have been synthesized. However, to reveal the anti-tumor mechanism and improve the efficacy of these artemisinin-type drugs, studies have been conducted in recent years. In this review, we first provide an overview of the effect of artemisinin-type drugs on the regulated cell death pathways, which may uncover novel therapeutic approaches. Then, to overcome the shortcomings of artemisinin-type drugs, we summarize the recent advances in two different therapeutic approaches, namely the combination therapy with biologics influencing regulated cell death, and the use of nanocarriers as drug delivery systems. For the former approach, we discuss the superiority of combination treatments compared to monotherapy in tumor cells based on their effects on regulated cell death. For the latter approach, we give a systematic overview of nanocarrier design principles used to deliver artemisinin-type drugs, including inorganic-based nanoparticles, liposomes, micelles, polymer-based nanoparticles, carbon-based nanoparticles, nanostructured lipid carriers and niosomes. Both approaches have yielded promising findings in vitro and in vivo, providing a strong scientific basis for further study and upcoming clinical trials.

AIM2 inhibits the proliferation, invasion and migration, and promotes the apoptosis of osteosarcoma cells by inactivating the PI3K/AKT/mTOR signaling pathway

Osteosarcoma is a primary bone tumor that mainly occurs in children and adolescents. Absent in melanoma 2 (AIM2) has been demonstrated to be involved in regulating the occurrence and development of cancer, exerting oncogenic and pro-cancer effects; however, its role in osteosarcoma is poorly understood. The present study aimed to explore the function and molecular mechanism of AIM2 in the progression of osteosarcoma. In the present study, AIM2 expression was predicted using the Cancer Cell Line Encyclopedia database and examined in several osteosarcoma cell lines using reverse transcription-quantitative PCR and western blotting. Following AIM2 overexpression, cell proliferation and apoptosis were examined using Cell Counting Kit-8, colony formation and TUNEL staining assays. The expression levels of proteins related to apoptosis, epithelial-mesenchymal transition (EMT) and the PI3K/AKT/mTOR signaling pathway were determined by western blotting. Additionally, cell invasion and migration were assessed using Transwell and wound healing assays. After addition of the PI3K/AKT/mTOR signaling pathway inhibitor LY294002 or activator 740Y-P, cell function analysis was performed. The results demonstrated that AIM2 was expressed at low levels in osteosarcoma cell lines. AIM2 overexpression inhibited proliferation, invasion, migration and EMT, and promoted apoptosis in osteosarcoma cells. Furthermore, the levels of phosphorylated (p)-PI3K, p-AKT and p-mTOR were markedly downregulated following AIM2 overexpression. Furthermore, LY294002 treatment had the same effects as AIM2 upregulation on osteosarcoma cell proliferation, apoptosis, invasion, migration and EMT. By contrast, 740Y-P reversed the effects of AIM2 overexpression on the behavior of osteosarcoma cells. Overall, the findings of the present study demonstrated that AIM2 may inhibit the progression of osteosarcoma by inactivating the PI3K/AKT/mTOR signaling pathway, and suggested that AIM2 may be a promising marker for the treatment of osteosarcoma.

Dihydroartemisinin mediating PKM2-caspase-8/3-GSDME axis for pyroptosis in esophageal squamous cell carcinoma

Pyroptosis is a novel type of pro-inflammatory programmed cell death that has been strongly reported to be related to inflammation, immune, and cancer. Dihydroartemisinin (DHA) has good anti-tumor properties. However, the exact mechanism by which DHA induces pyroptosis to inhibit esophageal squamous cell carcinoma (ESCC) remains unclear. After applying DHA treatment to ESCC, we found that some dying cells exhibited the characteristic morphology of pyroptosis, such as blowing large bubbles from the cell membrane, accompanied by downregulation of pyruvate kinase isoform M2 (PKM2), activation of caspase-8/3, and production of GSDME-NT. Meanwhile, it was accompanied by an increased release of LDH and inflammatory factors (IL-18 and IL-1β). Both knockdown of GSDME and application of caspase-8/3 specific inhibitors (z-ITED-FMK/Ac-DEVD-CHO) significantly inhibited DHA-induced pyroptosis. However, the former did not affect the activation of caspase-3. In contrast, overexpression of PKM2 inhibited caspase-8/3 activation as well as GSDME-N production. Furthermore, both si-GSDME and OE-PKM2 inhibited DHA-induced pyroptosis in vivo and in vitro. Therefore, the results suggest that DHA can induce pyroptosis of ESCC cells via the PKM2-caspase-8/3-GSDME pathway. Implication: In this study, we identified new mechanism of DHA in inhibiting ESCC development and progression, and provide a potential therapeutic agent for the treatment of ESCC.

Molecular mechanisms and therapeutic relevance of gasdermin E in human diseases

Gasdermin E (GSDME) is one of the main members of the GSDM family and is originally involved in hereditary hearing loss. Recent studies have reported that GSDME expression is epigenetically silenced by methylation in several common tumours, thereby enhancing tumour proliferation and metastasis. GSDME is also downregulated in cancer tissues compared with normal tissues, which suggests that GSDME can be considered a tumour suppressor. Furthermore, GSDME is the effector protein of caspase-3 and granzyme B in pyroptosis, and it plays a significant role in innate immunity, tissue damage, cancer, and hearing loss, thus revealing potential novel therapeutic avenues. A great deal of evidence reveals that GSDME can be implemented as a biomarker in cancer diagnosis and monitoring, chemotherapy, immunotherapy, and chemoresistance. Based on the current knowledge of GSDME, this review is focussed on its mechanism of action and the most recent advances in its role in cancer and normal physiology.

A Pyroptosis-Related Gene Panel in Prognosis Prediction and Immune Microenvironment of Human Endometrial Cancer

As the second common diagnosed cancer among gynecological tumors, endometrial cancer (EC) has heterogeneous pathogenesis and clinical manifestations. Therefore, prognosis prediction that considers gene expression value and clinical characteristics, is helpful to patients with EC. We downloaded RNA expression and clinical data from the TCGA database. We achieved 4 DEPRGs and constructed the PRG panel by univariate, lasso and multivariate Cox analysis. Based on the median value of the risk score, patients were divided into two groups. The Kaplan–Meier curve suggested that the patients with lower risk scores had better clinical outcomes of EC. AUC of ROC curves suggested the panel can be used as an independent predictor. Future analysis indicated the positive correlations between risk score and clinical characteristics. What’s more, we performed GO and KEGG functional analysis and immune environment exploration to get an understanding of the potential molecular mechanism and immunotherapeutic target. To future validate the panel, we found that the relapse-free and overall survival probability of 4 prognostic DEPRGs between high-expression group and low-expression group were different through the Kaplan–Meier plotter in UCEC. In addition, GEPIA database and RT-PCR experiment indicated GPX4 and GSDMD were highly expressed in UCEC compared to normal endometrial tissue, and TIRAP and ELANE were downregulated. This study identified a PRG panel to predict the prognosis immune microenvironment in human EC. Then, Kaplan–Meier analysis and AUC below the ROC curves was used to validate the panel. In addition, Chi-square was used to show the clinical significance. GO, KEGG and GSEA were used to show the functional differences. Different immune-related databases were used to analyze the immune characteristics. The Kaplan–Meier plotter website was used to assess the effect of genes on survival. GEPIA and RT-PCR were used to analyze the expression level. In summary, we identified 4 prognosis-associated pyroptosis-related genes (ELANE, GPX4, GSDMD, and TIRAP). The panel can also predict prognosis prediction and immune microenvironment in human endometrial cancer.

Identification of a Novel Pyroptosis-Related Gene Signature for Predicting Prognosis in Bladder Cancer

Bladder cancer (BC) has an unpredictable prognosis. Pyroptosis is a novel form of programmed cell death. However, whether the pyroptosis-related genes have a prognostic value remains unknown. In this study, we downloaded the mRNA expression and clinical data of BC patients and used the LASSO Cox analysis was employed to build a signature. High-risk patients had a significantly lower overall survival (OS) (p < .0001). Single-sample gene set enrichment analysis (ssGSEA) indicated that the tumor immune microenvironment was different between the two risk groups. In conclusion, a pyroptosis-related signature can be used for OS prediction of patients with BCs.

Comments on "Dihydroartemisinin induces pyroptosis by promoting the AIM2/caspase-3/DFNA5 axis in breast cancer cells."

We read the article "Dihydroartemisinin induces pyroptosis by promoting the AIM2/caspase-3/DFNA5 axis in breast cancer cells" published in Chemico-Biological Interactions. Authors revealed that dihydroartemisinin induced pyroptosis through activating the AIM2/caspase-3/DFNA5 pathway in breast cancer cells. However, some issues in this paper need to be commented. Authors suggested that dihydroartemisinin activated AIM2/caspase-3/DFNA5 axis in MCF-7 cell line. However, previous studies have confirmed that MCF-7 cell line does not express the caspase-3 protein. This makes us confused.