Ionizing Radiation Triggers the Antitumor Immunity by Inducing Gasdermin E-Mediated Pyroptosis in Tumor Cells

Pyroptosis and chemical classification of pyroptotic agents

Pyroptosis, as a lytic-inflammatory type of programmed cell death, has garnered considerable attention due to its role in cancer chemotherapy and many inflammatory diseases. This review will discuss the biochemical classification of pyroptotic inducers according to their chemical structure, pyroptotic mechanism, and cancer type of these targets. A structure-activity relationship study on pyroptotic inducers is revealed based on the surveyed pyroptotic inducer chemotherapeutics. The shared features in the chemical structures of current pyroptotic inducer agents were displayed, including an essential cyclic head, a vital linker, and a hydrophilic tail that is significant for π-π interactions and hydrogen bonding. The presented structural features will open the way to design new hybridized classes or scaffolds as potent pyroptotic inducers in the future, which may represent a solution to the apoptotic-resistance dilemma along with synergistic chemotherapeutic advantage.

Microbial Photosynthetic Oxygenation and Radiotherapeutic Sensitization Enables Pyroptosis Induction for Combinatorial Cancer Therapy

Rectal cancer surgery is challenging due to the complex anatomy, making it difficult to achieve clear surgical margins. Radiotherapy (RT) plays a crucial role, especially in treating locally recurrent rectal cancer and preserving anal function. However, its effectiveness is often limited by tumor hypoxia, particularly prevalent in hypoxic regions near the bowel wall in colorectal cancer. Hypoxia contributes to both radiation resistance and apoptosis resistance, compromising RT outcomes. To overcome hypoxia-driven radiotherapy resistance, this work designs and engineers a radiotherapy-sensitizing bioplatform for efficient cancer RT. It combines lanthanum oxide nanoparticles (La2O3 NPs) with cyanobacteria, which produces oxygen through photosynthesis. This bioplatform uniquely reduces tumor hypoxia, enhances radiation deposition, and improves RT efficacy. La2O3 NPs further enhance reactive oxygen species (ROS) production induced by radiation, triggering pyroptosis via the ROS-NLRP3-GSDMD pathway, while RT amplifies pyroptosis through GSDME, circumventing tumor apoptosis resistance. The further integrated thermosensitive hydrogels ensure precise localization of the bioplatform, reducing systemic toxicity and improving therapeutic specificity. Compared to conventional therapies, this dual-action system addresses hypoxia, RT resistance, and apoptosis resistance more effectively. In vivo and in vitro hypoxia models validate its potent anti-tumor efficacy, offering valuable insights for refining clinical treatment paradigms.

Therapeutic connections between pyroptosis and paclitaxel in anti-tumor effects: an updated review

As a form of inflammation-associated cell death, pyroptosis has gained widespread attention in recent years. Accumulating evidence indicates that pyroptosis regulates tumor growth and is associated with autoimmune disorders and inflammatory response. Paclitaxel, a traditional Chinese medicine, usually induces death of cancer cells as a chemotherapeutic agent. Previous studies have revealed that paclitaxel can exert an anti-tumor effect through a variety of cell death mechanisms, of which pyroptosis plays a pivotal role in inhibiting tumor growth and enhancing anti-tumor immunity. In this review, we summarize the current advances in therapeutic connections between pyroptosis and paclitaxel in anti-tumor effects.

A Pyroptosis Radiosensitizer Facilitates Hypoxic Tumor Necrosis

Hypoxia-related tumor radioresistance markedly impairs the efficacy of radiotherapy. Herein, a targeted radiosensitization strategy is introduced, leveraging the upregulation of gasdermin C (GSDMC) in hypoxic tumor cells, aiming to induce pyroptosis through the application of a cobalt-containing polyoxometalate-based radiosensitizer. This novel radiosensitizer is designed for the precisely controlled release of cobalt ions upon X-ray irradiation, thereby activating caspase-8 and prompting the cleavage of GSDMC. This sequence of events selectively triggers pyroptosis in hypoxic tumor cells, directly addressing radioresistance. The ensuing results highlight the enhanced radiotherapy efficacy and tumor necrosis both in vitro and in vivo models. Overall, the findings confirm the effectiveness of this strategy targeting high GSDMC expression in hypoxic tumors to induce pyroptosis for precise radiotherapy. Such findings encourage further exploration of hypoxia-driven pyroptosis to improve cancer treatment outcomes.

Preclinical and Clinical Feasibility Studies as the First Step Before Forthcoming Intravesical Instillation of [211At]At-anti-CA-IX Antibody (ATO-101™) Study in Patients with Non-Muscle-Invasive Bladder Cancer Unresponsive to Standard of Care

INTRODUCTION

Recently, alpha-emitting radionuclides like astatine-211 have offered promising results in clinical development. Non-muscle-invasive bladder cancer (NMIBC) presents a need for novel therapies. One promising approach is radioimmunotherapy targeting Carbonic Anhydrase IX (CA-IX), which is supported by preclinical and clinical evidence. The aim of our preclinical and clinical studies was to evaluate the [211At]At-anti-CA-IX antibody (ATO-101™) for future use in NMIBC patient care.

METHODS

The anti-CA-IX antibody, girentuximab (TLX250), was labeled with lutetium-177 and astatine-211 for in vitro studies. Affinity constant measurements of [211At]At-girentuximab in RT-112 cells were taken, and toxicity evaluations were conducted in vitro and in healthy mice. Additionally, a clinical proof-of-concept study, PERTINENCE, that used [89Zr]Zr-girentuximab for PET/CT imaging in bladder cancer patients was conducted.

RESULTS

The measurement of the affinity constant of [211At]At-girentuximab in RT112 cells revealed high binding affinity and significant cytotoxicity compared to [177Lu]Lu-girentuximab. Biodistribution studies in healthy mice indicated low systemic radioactivity uptake, and a bladder post-instillation examination showed no abnormalities in bladder mucosa, suggesting safety. In the PERTINENCE study, which involved patients with NMIBC tumors expressing CA-IX, [89Zr]Zr-girentuximab PET/CT showed no extravesical leakage. Wall bladder uptake spots correlated with recurrence or inflammatory reaction. A dosimetric study suggested the potential efficacy and favorable safety profile of intravesical alpha therapy with the [211At]At-anti-CA-IX antibody (ATO-101™) in NMIBC treatment.

CONCLUSIONS

Preclinical and clinical data demonstrate the promising therapeutic role of 211At-targeted alpha agents in NMIBC, and the [211At]At-anti-CA-IX antibody (ATO-101™) could fulfill this role. A phase I FIH clinical trial is in preparation, and results are expected within the next years.

5-FU@HFn combined with decitabine induces pyroptosis and enhances antitumor immunotherapy for chronic myeloid leukemia

BACKGROUND

Tyrosine kinase inhibitors (TKIs) constitute the primary treatment for chronic myeloid leukemia (CML). However, resistance to TKIs often leads to treatment failure. Pyroptosis, a form of programmed cell death, has emerged as a promising strategy in cancer therapy due to its ability to eliminate tumor cells while stimulating antitumor immunity. Low-dose decitabine (DAC) has been shown to reverse methylation-induced silencing of the pyroptosis-related gene gasdermin E (GSDME) in some tumor cells, offering a potential new therapeutic option for CML. Herein, we propose a combination therapy using 5-fluorouracil (5-FU), a broad-spectrum chemotherapeutic agent, and low-dose DAC to induce pyroptosis in CML cells via the caspase-3/GSDME pathway. However, the nonspecific targeting of 5-FU diminishes its pyroptosis efficacy and causes off-target toxicity, highlighting the need for a targeted drug delivery system.

RESULTS

In this study, we developed 5-FU@HFn nanoparticles (NPs) by loading 5-FU into the recombinant human heavy chain ferritin (HFn) nanocage through a high-temperature via the drug channels on the protein cage. The loading efficiency was approximately 50.62 ± 1.17 µg of 5-FU per mg of HFn. 5-FU@HFn NPs selectively targeted CML cells through CD71-mediated uptake, significantly enhancing the therapeutic effects of 5-FU. When combined with DAC, 5-FU@HFn NPs effectively activated pyroptosis via the caspase-3/GSDME pathway in both TKI-sensitive and TKI-resistant CML cells. In a CML mouse model, this combination therapy significantly suppressed tumorigenesis and triggered a robust antitumor immune response, facilitating the clearance of leukemic cells. Furthermore, the 5-FU@HFn NPs exhibited excellent in vivo safety.

CONCLUSIONS

The innovative therapeutic strategy, combining 5-FU@HFn nanoparticles with low-dose DAC, effectively induces caspase-3/GSDME-mediated pyroptosis and activates antitumor immunity for CML. This approach offers a potential alternative for patients resistant or intolerant to TKIs.

Gambogic acid induces GSDME dependent pyroptotic signaling pathway via ROS/P53/Mitochondria/Caspase-3 in ovarian cancer cells

Gambogic acid (GA) is a naturally active compound extracted from the Garcinia hanburyi with various anticancer activities. However, whether GA induces pyroptosis (a newly discovered inflammation-mediated programmed cell death mechanism) in ovarian cancer (OC) has not yet been reported. This study revealed that GA treatment reduced cell viability by inducing pyroptosis in OC cell lines. Typical pyroptosis morphological manifestations such as cell swelling with large bubbles and loss of cell membrane integrity, were observed. Cleaved caspase-3 and GSDME-N levels increased after GA treatment, and knocking out GSDME or using a caspase-3 inhibitor could switch GA-induced cell death from pyroptosis to apoptosis, indicating GA induced caspase-3/GSDME-dependent pyroptosis. Furthermore, this research indicated that GA significantly increased reactive oxygen species (ROS) and p53 phosphorylation. OC cells pretreated with ROS inhibitor N-Acetylcysteine (NAC) and the specific p53 inhibitor pifithrin-μ could completely reverse the pyroptosis post-treatment. Elevated p53 and phosphorylated p53 reduced mitochondrial membrane potential (MMP) and Bcl-2, increase the expression of Bax, and damage mitochondria by releasing cytochrome c to activate the downstream pyroptosis pathway. Different doses of GA inhibited tumor growth in ID8 tumor-bearing mice, and high-dose GA increased in tumor-infiltrating lymphocytes CD3, CD4, and CD8 were detected in tumor tissues. Notably, the expressions of GSDME-N, cleaved caspase-3 and other proteins were increased in tumor tissues with high-dose GA groups. These findings demonstrate that GA-treated OC cells could induce GSDME-mediated pyroptosis through the ROS/p53/mitochondria signaling pathway and caspase-3/-9 activation. Thus, GA is a promising therapeutic agent for OC treatment.

Berberine shaping the tumor immune landscape via pyroptosis

Pyroptosis is a programmed cell death (PCD) mainly mediated by the Gasdermin family of proteins, among which Gasdermin E (GSDME) is considered a tumor suppressor gene. GSDME can recruit immune cells to the tumor microenvironment (TME) and promote their effects. Activating and enhancing adaptive immunity through GSDME is a potential solution for anti-tumor therapy. Here we reported that berberine (BBR), a small molecule from traditional Chinese medicine, as a GSDME activator, induced caspase-3 (C-3)/GSDME pathway-mediated pyroptosis through the mitochondrial pathway, improved the immunosuppressive state of the tumor microenvironment, and thus promoted anti-tumor immunity. We determined the induction of pyroptosis of 4 T1 cells by BBR through various experiments, and investigated the immune activation effect of BBR by co-culture in vitro, which induced DCs maturation and macrophage polarization. Zebrafish embryo toxicity experiments were used to evaluate the in vivo safety of berberine. Furthermore, the in vivo antitumor and immune activation effects of BBR were investigated using 4 T1 orthotopic model mice, and the results showed that BBR could eliminate orthotopic tumor cells by activating local and systemic immunity. Moreover, we observed that BBR significantly inhibited breast cancer lung metastasis. In summary, our results showd the role of BBR as a GSDME activator stimulated both local and systemic antitumor immune responses by inducing pyroptosis, effectively preventing tumor development and metastasis.

The Role and Applied Value of Mitochondria in Glioma-Related Research

Mitochondria, known as the "energy factory" of cells, are essential organelles with a double membrane structure and genetic material found in most eukaryotic cells. They play a crucial role in tumorigenesis and development, with alterations in mitochondrial structure and function in tumor cells leading to characteristics such as rapid proliferation, invasion, and drug resistance. Glioma, the most common brain tumor with a high recurrence rate and limited treatment options, has been linked to changes in mitochondrial structure and function. This review focuses on the bioenergetics, dynamics, metastasis, and autophagy of mitochondria in relation to glioma proliferation, as well as the potential use of mitochondria-targeting drugs in glioma treatment.

RSPO3 regulates the radioresistance of Non-Small cell lung cancer cells via NLRP3 Inflammasome-Mediated pyroptosis

PURPOSE

Radioresistance is a significant challenge in the radiotherapy of non-small cell lung cancer (NSCLC). This study aimed to investigate the role of R-spondin 3 (RSPO3) in regulating NSCLC radioresistance.

METHODS AND MATERIALS

RNA sequencing was performed to analyze genes that are differentially expressed in radioresistant NSCLC cell lines. RSPO3 overexpression and knockdown experiments were conducted to assess its impact on radiosensitivity. The involvement of the β-catenin-NF-κB signaling pathway and the NLRP3 inflammasome in RSPO3-mediated radiosensitivity was also evaluated. In vivo experiments were conducted using a clinical-grade anti-RSPO3 antibody (OMP-131R10/rosmantuzumab) to assess its impact on radiation-induced pyroptosis and subsequent anti-tumor immunity.

RESULTS

RSPO3 expression was downregulated in radioresistant NSCLC cells. Overexpression of RSPO3 increased NSCLC radiosensitivity through the induction of pyroptosis, which was mediated by the β-catenin-NF-κB signaling pathway and the NLRP3 inflammasome. The anti-RSPO3 antibody effectively blocked radiation-induced pyroptosis and anti-tumor immunity in vivo. Conversely, upregulation of RSPO3 enhanced NSCLC tumor radiosensitivity.

CONCLUSIONS

The findings demonstrated that RSPO3 plays a crucial role in regulating NSCLC radioresistance via NLRP3 mediated pyroptosis. Targeting the RSPO3-NLRP3 inflammasome axis may offer a potential therapeutic strategy to enhance the efficacy of radiotherapy for NSCLC patients.

The Role of the Microbiome and of Radiotherapy-Derived Metabolites in Breast Cancer

The gut microbiome has emerged as a crucial player in modulating cancer therapies, including radiotherapy. In the case of breast cancer, the interplay between the microbiome and radiotherapy-derived metabolites may enhance therapeutic outcomes and minimize adverse effects. In this review, we explore the bidirectional relationship between the gut microbiome and breast cancer. We explain how gut microbiome composition influences cancer progression and treatment response, and how breast cancer and its treatments influence microbiome composition. A dual role for radiotherapy-derived metabolites is explored in this article, highlighting both their therapeutic benefits and potential hazards. By integrating genomics, metabolomics, and bioinformatics tools, we present a comprehensive overview of these interactions. The study provides real-world insight through case studies and clinical trials, while therapeutic innovations such as probiotics, and dietary interventions are examined for their potential to modulate the microbiome and enhance treatment effectiveness. Moreover, ethical considerations and patient perspectives are discussed, ensuring a comprehensive understanding of the subject. Towards revolutionizing treatment strategies and improving patient outcomes, the review concludes with future research directions. It also envisions integrating microbiome and metabolite research into personalized breast cancer therapy.

Oxidative cell death in cancer: mechanisms and therapeutic opportunities

Reactive oxygen species (ROS) are highly reactive oxygen-containing molecules generated as natural byproducts during cellular processes, including metabolism. Under normal conditions, ROS play crucial roles in diverse cellular functions, including cell signaling and immune responses. However, a disturbance in the balance between ROS production and cellular antioxidant defenses can lead to an excessive ROS buildup, causing oxidative stress. This stress damages essential cellular components, including lipids, proteins, and DNA, potentially culminating in oxidative cell death. This form of cell death can take various forms, such as ferroptosis, apoptosis, necroptosis, pyroptosis, paraptosis, parthanatos, and oxeiptosis, each displaying distinct genetic, biochemical, and signaling characteristics. The investigation of oxidative cell death holds promise for the development of pharmacological agents that are used to prevent tumorigenesis or treat established cancer. Specifically, targeting key antioxidant proteins, such as SLC7A11, GCLC, GPX4, TXN, and TXNRD, represents an emerging approach for inducing oxidative cell death in cancer cells. This review provides a comprehensive summary of recent progress, opportunities, and challenges in targeting oxidative cell death for cancer therapy.

The Latest Look at PDT and Immune Checkpoints

Photodynamic therapy (PDT) can not only directly eliminate cancer cells, but can also stimulate antitumor immune responses. It also affects the expression of immune checkpoints. The purpose of this review is to collect, analyze, and summarize recent news about PDT and immune checkpoints, along with their inhibitors, and to identify future research directions that may enhance the effectiveness of this approach. A search for research articles published between January 2023 and March 2024 was conducted in PubMed/MEDLINE. Eligibility criteria were as follows: (1) papers describing PDT and immune checkpoints, (2) only original research papers, (3) only papers describing new reports in the field of PDT and immune checkpoints, and (4) both in vitro and in vivo papers. Exclusion criteria included (1) papers written in a language other than Polish or English, (2) review papers, and (3) papers published before January 2023. 24 papers describing new data on PDT and immune checkpoints have been published since January 2023. These included information on the effects of PDT on immune checkpoints, and attempts to associate PDT with ICI and with other molecules to modulate immune checkpoints, improve the immunosuppressive environment of the tumor, and resolve PDT-related problems. They also focused on the development of new nanoparticles that can improve the delivery of photosensitizers and drugs selectively to the tumor. The effect of PDT on the level of immune checkpoints and the associated activity of the immune system has not been fully elucidated further, and reports in this area are divergent, indicating the complexity of the interaction between PDT and the immune system. PDT-based strategies have been shown to have a beneficial effect on the delivery of ICI to the tumor. The utility of PDT in enhancing the induction of the antitumor response by participating in the triggering of immunogenic cell death, the exposure of tumor antigens, and the release of various alarm signals that together promote the activation of dendritic cells and other components of the immune system has also been demonstrated, with the result that PDT can enhance the antitumor immune response induced by ICI therapy. PDT also enables multifaceted regulation of the tumor's immunosuppressive environment, as a result of which ICI therapy has the potential to achieve better antitumor efficacy. The current review has presented evidence of PDT's ability to modulate the level of immune checkpoints and the effectiveness of the association of PDT with ICIs and other molecules in inducing an effective immune response against cancer cells. However, these studies are at an early stage and many more observations need to be made to confirm their efficacy. The new research directions indicated may contribute to the development of further strategies.

Nanomaterials Enhance Pyroptosis-Based Tumor Immunotherapy

Pyroptosis, a pro-inflammatory and lytic programmed cell death pathway, possesses great potential for antitumor immunotherapy. By releasing cellular contents and a large number of pro-inflammatory factors, tumor cell pyroptosis can promote dendritic cell maturation, increase the intratumoral infiltration of cytotoxic T cells and natural killer cells, and reduce the number of immunosuppressive cells within the tumor. However, the efficient induction of pyroptosis and prevention of damage to normal tissues or cells is an urgent concern to be addressed. Recently, a wide variety of nanoplatforms have been designed to precisely trigger pyroptosis and activate the antitumor immune responses. This review provides an update on the progress in nanotechnology for enhancing pyroptosis-based tumor immunotherapy. Nanomaterials have shown great advantages in triggering pyroptosis by delivering pyroptosis initiators to tumors, increasing oxidative stress in tumor cells, and inducing intracellular osmotic pressure changes or ion imbalances. In addition, the challenges and future perspectives in this field are proposed to advance the clinical translation of pyroptosis-inducing nanomedicines.

Effect of Rosmarinic Acid on Cell Proliferation, Oxidative Stress, and Apoptosis Pathways in an Animal Model of Induced Glioblastoma Multiforme

BACKGROUND

In brain tumors, the complexity of the pathophysiological processes such as oxidative stress, cell proliferation, angiogenesis, and apoptosis have seriously challenged the definitive treatment. Rosmarinic acid (RA), as a polyphenolic compound, has been found to prevent tumor progression in some aggressive cancers. This study was designed to evaluate the anticancer effects of RA on brain tumors.

METHOD

Rats were divided into six groups. Implantation of C6 glioma cells was carried out in the caudate nucleus of the right hemisphere. RA at doses of 5, 10, and 20 mg/kg (i.p.) was administered to the treatment groups for seven days. Tumor volume (by MRI imaging), locomotor ability, survival time, histological alterations (by H & E staining), expression of p53 and p21 mRNAs (by RT-PCR), activities of antioxidant enzymes (superoxide dismutase [SOD] and catalase [CAT] by assay kits), expression of caspase-3 and VEGF (by immunohistochemical analysis), and TUNEL-positive cells (by tunnel staining) were analyzed.

RESULTS

The results indicated that the RA at a dose of 20 mg/kg reduced the tumor volume, prolonged survival time, increased p53 and p21 mRNAs, attenuated SOD and CAT activities in tumor tissue, elevated caspase-3, and increased the number of TUNEL-positive cells. Furthermore, histological analysis revealed less invasion of tumor cells into the normal parenchyma in rats treated with RA (20 mg/kg).

CONCLUSION

These findings provide evidence that the ability of RA to reduce tumor volume could be related to factors that modulate oxidative stress (SOD and CAT enzymes), cell proliferation (p53 and p21), and apoptosis (caspase-3).

Synergistically Augmenting Cancer Immunotherapy by Physical Manipulation of Pyroptosis Induction

Pyroptosis is a newly recognized type of programmed cell death mediated by the gasdermin family and caspase. It is characterized by the formation of inflammasomes and the following inflammatory responses. Recent studies have elucidated the value of pyroptosis induction in cancer treatment. The inflammatory cytokines produced during pyroptosis can trigger immune responses to suppress malignancy. Physical approaches for cancer treatment, including radiotherapy, light-based techniques (photodynamic and photothermal therapy), ultrasound-based techniques (sonodynamic therapy and focused ultrasound), and electricity-based techniques (irreversible electroporation and radiofrequency ablation), are effective in clinical application. Recent studies have reported that pyroptosis is involved in the treatment process of physical approaches. Manipulating pyroptosis using physical approaches can be utilized in combating cancer, according to recent studies. Pyroptosis-triggered immunotherapy can be combined with the original anti-tumor methods to achieve a synergistic therapy and improve the therapeutic effect. Studies have also revealed that enhancing pyroptosis may increase the sensitivity of cancer cells to some physical approaches. Herein, we present a comprehensive review of the literature focusing on the associations between pyroptosis and various physical approaches for cancer and its underlying mechanisms. We also discussed the role of pyroptosis-triggered immunotherapy in the treatment process of physical manipulation.

Prognostic value of different radiation-related cell death genes in patients with lung adenocarcinoma

BACKGROUND AND AIMS

Radiotherapy is widely applied for lung adenocarcinoma (LUAD), while individualized differences led to different outcomes. This study aimed to establish a multi-gene risk scoring model to predict the benefits of LUAD patients from radiotherapy, based on different types of cell death respectively.

RESULTS

Other than autophagy, pyroptosis, ferroptosis and Immunogenic cell death (ICD), the LUAD prognostic model based on apoptosis had the best performance, and the area under curves (AUCs) of the receiver operating curve (ROC) for 1-, 3-, and 5-year OS were 0.700,0.736,0.723,respectively. Such genes were involved as SLC7A5, EXO1, ABAT, NLRP1 and GAR1. Then patients were divided into high and low risk groups by the median apoptosis-LUAD risk score. For patients in the high-risk group, i.e., the radiotherapy-tolerant group, we screened adjuvant chemotherapy and found that besides the conventional first-line chemotherapy regimen, drugs such as Fludarabine, Pevonedistat, and Podophyllotoxin Bromide may also have potential therapeutic value.

CONCLUSION

The multi-gene risk scoring model based on apoptosis might predict the radiotherapy benefits of LUAD patients and for those radioresistant patients classified by the model we also provided effective adjuvant chemicals, which would be used to guide clinical treatment.

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.

The Emerging Role of Deubiquitinases in Radiosensitivity

Radiation therapy is a primary treatment for cancer, but radioresistance remains a significant challenge in improving efficacy and reducing toxicity. Accumulating evidence suggests that deubiquitinases (DUBs) play a crucial role in regulating cell sensitivity to ionizing radiation. Traditional small-molecule DUB inhibitors have demonstrated radiosensitization effects, and novel deubiquitinase-targeting chimeras (DUBTACs) provide a promising strategy for radiosensitizer development by harnessing the ubiquitin-proteasome system. This review highlights the mechanisms by which DUBs regulate radiosensitivity, including DNA damage repair, the cell cycle, cell death, and hypoxia. Progress on DUB inhibitors and DUBTACs is summarized, and their potential radiosensitization effects are discussed. Developing drugs targeting DUBs appears to be a promising alternative approach to overcoming radioresistance, warranting further research into their mechanisms.

Isofraxidin attenuates dextran sulfate sodium-induced ulcerative colitis through inhibiting pyroptosis by upregulating Nrf2 and reducing reactive oxidative species

BACKGROUND

Ulcerative colitis (UC), a non-specific gastrointestinal disease, is commonly managed with aminosalicylic acids and immunosuppressive agents to control inflammation and relieve symptoms, despite frequent relapses. Isofraxidin is a coumarin compound extracted from traditional Chinese medicine, exhibiting anti-inflammatory and antioxidant properties; however, its alleviating effect on UC remains unclear. Therefore, we investigated the mechanism of isofraxidin in lipopolysaccharide (LPS)-induced cell inflammation in human intestinal epithelial cell (HIEC) and human colorectal adenocarcinoma cells (Caco-2), as well as in dextran sulfate sodium (DSS)-induced UC in mice.

METHODS

We established colitis models in HIEC and Caco-2 cells and mice with LPS and DSS, respectively. Additionally, NLRP3 knockout mice and HIEC cells transfected with NLRP3 silencing gene and ML385 illustrated the role of isofraxidin in pyroptosis and oxidative stress. Data from cells and mice analyses were subjected to one-way analysis of variance or a paired t-test.

RESULTS

Isofraxidin significantly alleviated LPS-induced cell inflammation and reduced lactic dehydrogenase release. Isofraxidin also reversed DSS- or LPS-induced pyroptosis in vivo and in vitro, increasing the expression of pyroptosis-related proteins. Moreover, isofraxidin alleviated oxidative stress induced by DSS or LPS, reducing reactive oxidative species (ROS), upregulation nuclear factor erythroid 2-related factor 2 (Nrf2), and promoting its entry into the nucleus. Mechanistically, ML385 reversed the inhibitory effect of isofraxidin on ROS and increased pyroptosis.

CONCLUSION

Isofraxidin can inhibit pyroptosis through upregulating Nrf2, promoting its entry into the nucleus, and reducing ROS, thereby alleviating DSS-induced UC. Our results suggest isofraxidin as a promising therapeutic strategy for UC treatment.

Pyroptotic cell death: an emerging therapeutic opportunity for radiotherapy

Pyroptotic cell death, an inflammatory form of programmed cell death (PCD), is emerging as a potential therapeutic opportunity for radiotherapy (RT). RT is commonly used for cancer treatment, but its effectiveness can be limited by tumor resistance and adverse effects on healthy tissues. Pyroptosis, characterized by cell swelling, membrane rupture, and release of pro-inflammatory cytokines, has been shown to enhance the immune response against cancer cells. By inducing pyroptotic cell death in tumor cells, RT has the potential to enhance treatment outcomes by stimulating anti-tumor immune responses and improving the overall efficacy of RT. Furthermore, the release of danger signals from pyroptotic cells can promote the recruitment and activation of immune cells, leading to a systemic immune response that may target distant metastases. Although further research is needed to fully understand the mechanisms and optimize the use of pyroptotic cell death in RT, it holds promise as a novel therapeutic strategy for improving cancer treatment outcomes. This review aims to synthesize recent research on the regulatory mechanisms underlying radiation-induced pyroptosis and to elucidate the potential significance of this process in RT. The insights gained from this analysis may inform strategies to enhance the efficacy of RT for tumors.

Tolerogenic dendritic cells in radiation-induced lung injury

Radiation-induced lung injury is a common complication associated with radiotherapy. It is characterized by early-stage radiation pneumonia and subsequent radiation pulmonary fibrosis. However, there is currently a lack of effective therapeutic strategies for radiation-induced lung injury. Recent studies have shown that tolerogenic dendritic cells interact with regulatory T cells and/or regulatory B cells to stimulate the production of immunosuppressive molecules, control inflammation, and prevent overimmunity. This highlights a potential new therapeutic activity of tolerogenic dendritic cells in managing radiation-induced lung injury. In this review, we aim to provide a comprehensive overview of tolerogenic dendritic cells in the context of radiation-induced lung injury, which will be valuable for researchers in this field.

Pyroptosis in glioma: Current management and future application

Glioma, the predominant form of central nervous system (CNS) malignancies, presents a significant challenge due to its high prevalence and low 5-year survival rate. The efficacy of current treatment methods is limited by the presence of the blood-brain barrier, the immunosuppressive microenvironment, and other factors. Immunotherapy has emerged as a promising approach, as it can overcome the blood-brain barrier. A tumor's immune privilege, which is induced by an immunosuppressive environment, constricts immunotherapy's clinical impact in glioma. Pyroptosis, a programmed cell death mechanism facilitated by gasdermins, plays a significant role in the management of glioma. Its ability to initiate and regulate tumor occurrence, progression, and metastasis is well-established. However, it is crucial to note that uncontrolled or excessive cell death can result in tissue damage, acute inflammation, and cytokine release syndrome, thereby potentially promoting tumor advancement or recurrence. This paper aims to elucidate the molecular pathways involved in pyroptosis and subsequently discuss its induction in cancer therapy. In addition, the current treatment methods of glioma and the use of pyroptosis in these treatments are introduced. It is hoped to provide more ideas for the treatment of glioma.

Modulation of CD8+ T Cell Responses by Radiotherapy-Current Evidence and Rationale for Combination with Immune Checkpoint Inhibitors

Radiotherapy for cancer has been known to affect the responses of immune cells, especially those of CD8+ T cells that play a pivotal role in anti-tumor immunity. Clinical success of immune checkpoint inhibitors led to an increasing interest in the ability of radiation to modulate CD8+ T cell responses. Recent studies that carefully analyzed CD8+ T cell responses following radiotherapy suggest the beneficial roles of radiotherapy on anti-tumor immunity. In addition, numerous clinical trials to evaluate the efficacy of combining radiotherapy with immune checkpoint inhibitors are currently undergoing. In this review, we summarize the current status of knowledge regarding the changes in CD8+ T cells following radiotherapy from various preclinical and clinical studies. Furthermore, key biological mechanisms that underlie such modulation, including both direct and indirect effects, are described. Lastly, we discuss the current evidence and essential considerations for harnessing radiotherapy as a combination partner for immune checkpoint inhibitors.

Apoptosis, necroptosis, and pyroptosis as alternative cell death pathways induced by chemotherapeutic agents?

For decades, common chemotherapeutic drugs have been established to trigger apoptosis, the preferred immunologically "silent" form of cell death. The primary objective of this review was to show that various FDA-approved chemotherapeutic drugs, including cisplatin, cyclosporine, doxorubicin, etoposide, 5-fluorouracil, gemcitabine, paclitaxel, or vinblastine can trigger necroptosis and pyroptosis. We aimed to provide the advantages and disadvantages of the induction of the given type of cell death by chemotherapeutical agents. Moreover, we give a short overview of the molecular mechanism of each type of cell death and indicate the existing crosstalks between cell death types. Finally, we provide a comparison of cell death types to facilitate the exploration of cell death types induced by other chemotherapeutical agents. Understanding the cell death pathway induced by a drug can lessen side effects and assist the discovery of new combinations with synergistic effects and low systemic toxicity.

Combination Therapy of Immune Checkpoint Inhibitors with Locoregional Therapy for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is estimated to be the fourth leading cause of cancer-related deaths globally, and its overall prognosis is dismal because most cases are diagnosed at a late stage and are unamenable to curative treatment. The emergence of immune checkpoint inhibitors (ICIs) has dramatically improved the therapeutic efficacy for advanced hepatocellular carcinoma; however, their response rates remain unsatisfactory, partly because >50% of HCC exhibit an ICI-nonresponsive tumor microenvironment characterized by a paucity of cytotoxic T cells (immune-cold), as well as difficulty in their infiltration into tumor sites (immune excluded). To overcome this limitation, combination therapies with locoregional therapies, including ablation, transarterial embolization, and radiotherapy, which are usually used for early stage HCCs, have been actively explored to enhance ICI efficacy by promoting the release of tumor-associated antigens and cytokines, and eventually accelerating the so-called cancer-immunity cycle. Various combination therapies have been investigated in early- to late-phase clinical trials, and some have shown promising results. This comprehensive article provides an overview of the immune landscape for HCC to understand ICI efficacy and its limitations and, subsequently, reviews the status of combinatorial therapies of ICIs with locoregional therapy for HCC.

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.

Advances in mitophagy and mitochondrial apoptosis pathway-related drugs in glioblastoma treatment

Glioblastoma (GBM) is the most common malignant tumor of the central nervous system (CNS). It is a leading cause of death among patients with intracranial malignant tumors. GBM exhibits intra- and inter-tumor heterogeneity, leading to drug resistance and eventual tumor recurrence. Conventional treatments for GBM include maximum surgical resection of glioma tissue, temozolomide administration, and radiotherapy, but these methods do not effectively halt cancer progression. Therefore, development of novel methods for the treatment of GBM and identification of new therapeutic targets are urgently required. In recent years, studies have shown that drugs related to mitophagy and mitochondrial apoptosis pathways can promote the death of glioblastoma cells by inducing mitochondrial damage, impairing adenosine triphosphate (ATP) synthesis, and depleting large amounts of ATP. Some studies have also shown that modern nano-drug delivery technology targeting mitochondria can achieve better drug release and deeper tissue penetration, suggesting that mitochondria could be a new target for intervention and therapy. The combination of drugs targeting mitochondrial apoptosis and autophagy pathways with nanotechnology is a promising novel approach for treating GBM.This article reviews the current status of drug therapy for GBM, drugs targeting mitophagy and mitochondrial apoptosis pathways, the potential of mitochondria as a new target for GBM treatment, the latest developments pertaining to GBM treatment, and promising directions for future research.

Self-assembled albumin nanoparticles induce pyroptosis for photodynamic/photothermal/immuno synergistic therapies in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is characterized by a high degree of malignancy, early metastasis, limited treatment, and poor prognosis. Immunotherapy, as a new and most promising treatment for cancer, has limited efficacy in TNBC because of the immunosuppressive tumor microenvironment (TME). Inducing pyroptosis and activating the cyclic guanosine monophosphate-adenosine monophosphate synthase/interferon gene stimulator (cGAS/STING) signaling pathway to upregulate innate immunity have become an emerging strategy for enhancing tumor immunotherapy. In this study, albumin nanospheres were constructed with photosensitizer-IR780 encapsulated in the core and cGAS-STING agonists/H₂S producer-ZnS loaded on the shell (named IR780-ZnS@HSA). In vitro, IR780-ZnS@HSA produced photothermal therapy (PTT) and photodynamic therapy (PDT) effects. In addition, it stimulated immunogenic cell death (ICD) and activated pyroptosis in tumor cells via the caspase-3-GSDME signaling pathway. IR780-ZnS@HSA also activated the cGAS-STING signaling pathway. The two pathways synergistically boost immune response. In vivo, IR780-ZnS@HSA + laser significantly inhibited tumor growth in 4T1 tumor-bearing mice and triggered an immune response, improving the efficacy of the anti-APD-L1 antibody (aPD-L1). In conclusion, IR780-ZnS@HSA, as a novel inducer of pyroptosis, can significantly inhibit tumor growth and improve the efficacy of aPD-L1.

The pyroptotic role of Caspase-3/GSDME signalling pathway among various cancer: A Review

Cytotoxic drugs have long been recognised to kill cancer cells through apoptosis. According to a current study, pyroptosis inhibits cell proliferation and shrinks tumors. Pyroptosis and apoptosis are caspase-dependent programmed cell death (PCD) processes. Inflammasomes activate caspase-1 and latent cytokines, including IL-1β and IL-18, to cleave gasdermin E (GSDME) and induce pyroptosis. Gasdermin proteins activate caspase-3 to induce pyroptosis, which is associated with tumour genesis, development, and therapy response. These proteins may serve as therapeutic biomarkers for cancer detection, and their antagonists may be a new target. Caspase-3, a crucial protein in both pyroptosis and apoptosis, governs tumour cytotoxicity when activated, and GSDME expression modulates this. Once active caspase-3 cleaves GSDME, its N-terminal domain punches holes in the cell membrane, causing it to expand, burst, and die. To understand the cellular and molecular mechanisms of PCD mediated by caspase-3 and GSDME, we focused on pyroptosis. Hence, caspase-3 and GSDME may be promising targets for cancer treatment.

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.

T lymphocyte-mediated pyroptosis: A new regulatory mechanism in non-viral liver disease

T lymphocyte-mediated pyroptosis plays an important role in the development of non-viral liver diseases. Pyroptosis as a programmed cell death process, has been a hot topic of research on disease pathogenesis in recent years. As one of the most common immune cells in the body, T cells are the major players in adaptive immunity. An increasing number of studies have shown that T lymphocyte-mediated pyroptosis functions in non-viral liver diseases to regulate immune function, alter the immune microenvironment, and thus influence disease progression. These findings will guide us and provide new ideas for the development of subsequent therapeutic agents for non-viral liver diseases.

Spatiotemporal local and abscopal cell death and immune responses to histotripsy focused ultrasound tumor ablation

Introduction

Histotripsy is a novel focused ultrasound tumor ablation modality with potent immunostimulatory effects.

Methods

To measure the spatiotemporal kinetics of local andabscopal responses to histotripsy, C57BL/6 mice bearing bilateral flank B16 melanoma or Hepa1-6 hepatocellular carcinoma tumors were treated with unilateral sham or partial histotripsy. Treated and contralateral untreated (abscopal) tumors were analyzed using multicolor immunofluorescence, digital spatial profiling, RNA sequencing (RNASeq), and flow cytometry.

Results

Unilateral histotripsy triggered abscopal tumor growth inhibition. Within the ablation zone, early high mobility group box protein 1 (HMGB1) release and necroptosis were accompanied by immunogenic cell death transcriptional responses in tumor cells and innate immune activation transcriptional responses in infiltrating myeloid and natural killer (NK) cells. Delayed CD8+ T cell intratumoral infiltration was spatiotemporally aligned with cancer cell features of ferroptosis; this effect was enhanced by CTLA-4 blockade and recapitulated in vitro when tumor-draining lymph node CD8+ T cells were co-cultured with tumor cells. Inoculation with cell-free tumor fractions generated by histotripsy but not radiation or freeze/thaw conferred partial protection from tumor challenge.

Discussion

We propose that histotripsy may evoke local necroptotic immunogenic cell death, priming systemic adaptive immune responses and abscopal ferroptotic cancer cell death.

Marine-Derived Natural Product HDYL-GQQ-495 Targets P62 to Inhibit Autophagy

Autophagy is widely implicated in pathophysiological processes such as tumors and metabolic and neurodegenerative disorders, making it an attractive target for drug discovery. Several chemical screening approaches have been developed to uncover autophagy-modulating compounds. However, the modulation capacity of marine compounds with significant pharmacological activities is largely unknown. We constructed an EGFP^KI-LC3B cell line using the CRISPR/Cas9 knock-in strategy in which green fluorescence indicated endogenous autophagy regulation. Using this cell line, we screened a compound library of approximately 500 marine natural products and analogues to investigate molecules that altered the EGFP fluorescence. We identified eight potential candidates that enhanced EGFP fluorescence, and HDYL-GQQ-495 was the leading one. Further validation with immunoblotting demonstrated that cleaved LC3 was increased in dose- and time-dependent manners, and the autophagy adaptor P62 showed oligomerization after HDYL-GQQ-495 treatment. We also demonstrated that HDYL-GQQ-495 treatment caused autophagy substrate aggregation, which indicated that HDYL-GQQ-495 serves as an autophagy inhibitor. Furthermore, HDYL-GQQ-495 induced Gasdermin E (GSDME) cleavage and promoted pyroptosis. Moreover, HDYL-GQQ-495 directly combined with P62 to induce P62 polymerization. In P62 knockout cells, the cleavage of LC3 or GSDME was blocked after HDYL-GQQ-495 treatment. The EGFP^KI-LC3B cell line was an effective tool for autophagy modulator screening. Using this tool, we found a novel marine-derived compound, HDYL-GQQ-495, targeting P62 to inhibit autophagy and promote pyroptosis.

Nanomedicine embraces cancer radio-immunotherapy: mechanism, design, recent advances, and clinical translation

Cancer radio-immunotherapy, integrating external/internal radiation therapy with immuno-oncology treatments, emerges in the current management of cancer. A growing number of pre-clinical studies and clinical trials have recently validated the synergistic antitumor effect of radio-immunotherapy, far beyond the "abscopal effect", but it suffers from a low response rate and toxicity issues. To this end, nanomedicines with an optimized design have been introduced to improve cancer radio-immunotherapy. Specifically, these nanomedicines are elegantly prepared by incorporating tumor antigens, immuno- or radio-regulators, or biomarker-specific imaging agents into the corresponding optimized nanoformulations. Moreover, they contribute to inducing various biological effects, such as generating in situ vaccination, promoting immunogenic cell death, overcoming radiation resistance, reversing immunosuppression, as well as pre-stratifying patients and assessing therapeutic response or therapy-induced toxicity. Overall, this review aims to provide a comprehensive landscape of nanomedicine-assisted radio-immunotherapy. The underlying working principles and the corresponding design strategies for these nanomedicines are elaborated by following the concept of "from bench to clinic". Their state-of-the-art applications, concerns over their clinical translation, along with perspectives are covered.