A systematic pan-cancer analysis of the gasdermin (GSDM) family of genes and their correlation with prognosis, the tumor microenvironment, and drug sensitivity

Gasdermin E as a potential target and biomarker for CRISPR-Cas9-based cancer therapy

Gasdermin E (GSDME), a protein pivotal in mediating pyroptosis, has gained significant attention due to its role in cancer pathogenesis and its potential as a therapeutic target. The advent of CRISPR-Cas9, a precise genome editing tool, has revolutionized cancer therapy by enabling the manipulation of GSDME expression and function. This review explores the interplay of GSDME and CRISPR-Cas9 in cancer, emphasizing GSDME's unique mechanism of cleavage-dependent pore formation in the cell membrane and its emerging applications as both a therapeutic target and a diagnostic biomarker. We discuss the potential and challenges of using GSDME-induced pyroptosis as a therapeutic strategy and how can enhance its efficacy and specificity. We conclude by highlighting promising future research directions in this emerging field.

GSDMD is a novel predictive biomarker for immunotherapy response: in the pan-cancer and single cell landscapes

Background

Gasdermin D (GSDMD), a key executor of pyroptosis, has been implicated in modulating the tumor immune microenvironment. However, its role as a predictive biomarker for immunotherapy response remains unclear.

Methods

We conducted a pan-cancer analysis of GSDMD expression across TCGA datasets and investigated its association with tumor mutational burden (TMB), microsatellite instability (MSI), and mismatch repair (MMR) status. Immunological relevance was further assessed by correlating GSDMD expression with immune cell infiltration and immune checkpoint gene signatures. We performed single-cell RNA sequencing analysis to investigate the immune cell populations and immunological pathways associated with GSDMD expression. Finally, organoid-based functional assays confirmed that Poly ADP-ribose polymerase inhibitors (PARPi) exert antitumor effects at least in part by enhancing GSDMD-mediated pyroptosis.

Results

GSDMD was found to be aberrantly expressed in multiple tumor types and positively correlated with TMB, MSI, and immune checkpoint expression. High GSDMD expression was associated with increased infiltration of pro-inflammatory immune cells. In organoid models, GSDMD expression influenced sensitivity to PARPi, suggesting a potential role in shaping the immune-responsive phenotype.

Conclusion

Our findings highlight GSDMD as a potential biomarker for predicting immunotherapy response and as a modulator of tumor-immune interactions. These results provide a foundation for future studies exploring GSDMD-targeted strategies to enhance immunotherapeutic efficacy.

Caspases: structural and molecular mechanisms and functions in cell death, innate immunity, and disease

Caspases are critical regulators of cell death, development, innate immunity, host defense, and disease. Upon detection of pathogens, damage-associated molecular patterns, cytokines, or other homeostatic disruptions, innate immune sensors, such as NLRs, activate caspases to initiate distinct regulated cell death pathways, including non-lytic (apoptosis) and innate immune lytic (pyroptosis and PANoptosis) pathways. These cell death pathways are driven by specific caspases and distinguished by their unique molecular mechanisms, supramolecular complexes, and enzymatic properties. Traditionally, caspases are classified as either apoptotic (caspase-2, -3, -6, -7, -8, -9, and -10) or inflammatory (caspase-1, -4, -5, and -11). However, extensive data from the past decades have shown that apoptotic caspases can also drive lytic inflammatory cell death downstream of innate immune sensing and inflammatory responses, such as in the case of caspase-3, -6, -7, and -8. Therefore, more inclusive classification systems based on function, substrate specificity, or the presence of pro-domains have been proposed to better reflect the multifaceted roles of caspases. In this review, we categorize caspases into CARD-, DED-, and short/no pro-domain-containing groups and examine their critical functions in innate immunity and cell death, along with their structural and molecular mechanisms, including active site/exosite properties and substrates. Additionally, we highlight the emerging roles of caspases in cellular homeostasis and therapeutic targeting. Given the clinical relevance of caspases across multiple diseases, improved understanding of these proteins and their structure-function relationships is critical for developing effective treatment strategies.

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.

Identification of immune characteristics of two lung adenocarcinoma subtypes based on immune- and pyroptosis-related genes to improve immunotherapy

BACKGROUND

Lung adenocarcinoma (LUAD) is the most prevalent histological subtype of lung cancer. Pyroptosis is a programmatic cell death linked to inflammation.

METHODS

The data information of 541 LUAD samples and 59 normal samples were obtained from TCGA database. The analysis of differentially expressed genes (DEGs) was carried out on LUAD patients. The intersection of integrated PRGs and IRGs with DEGs yielded IPRGs. We utilized univariate Cox regression to determine IPRGs linked to overall survival (OS). Based on their expression levels, unsupervised clustering of LUAD was conducted. Patients were divided into two clusters. Analyses of immunity and drugs were performed in two clusters.

RESULTS

One hundred and thirty-two IPRGs were linked with OS. Cluster 1 had a longer OS. Two thousand two hundred and fifty-six DEGs were detected in various subtypes. The results of immune analysis showed that most of the immune cells in cluster 2, which had a worse prognosis, had a low degree of infiltration. High Th2 cell infiltration may be related to poor prognosis in LUAD patients. Higher tumor immune dysfunction and exclusion (TIDE) and immunophenotypic scores in Cluster 1 indicated that these patients may have a better response to immunotherapy. There were significant differences in human leukocyte antigen (HLA), immune checkpoints, immunophenoscore (IPS), and TIDE scores in the two subtypes. The mutation frequencies of the top 10 genes in cluster 2 were higher than those in cluster 1. Different subtypes also had distinct sensitivities to different drugs.

CONCLUSION

IPRGs can be utilized for LUAD subtyping. Different subtypes have varied immune landscapes and immunotherapy responses.

Crosstalk of pyroptosis and cytokine in the tumor microenvironment: from mechanisms to clinical implication

In the realm of cancer research, the tumor microenvironment (TME) plays a crucial role in tumor initiation and progression, shaped by complex interactions between cancer cells and surrounding non-cancerous cells. Cytokines, as essential immunomodulatory agents, are secreted by various cellular constituents within the TME, including immune cells, cancer-associated fibroblasts, and cancer cells themselves. These cytokines facilitate intricate communication networks that significantly influence tumor initiation, progression, metastasis, and immune suppression. Pyroptosis contributes to TME remodeling by promoting the release of pro-inflammatory cytokines and sustaining chronic inflammation, impacting processes such as immune escape and angiogenesis. However, challenges remain due to the complex interplay among cytokines, pyroptosis, and the TME, along with the dual effects of pyroptosis on cancer progression and therapy-related complications like cytokine release syndrome. Unraveling these complexities could facilitate strategies that balance inflammatory responses while minimizing tissue damage during therapy. This review delves into the complex crosstalk between cytokines, pyroptosis, and the TME, elucidating their contribution to tumor progression and metastasis. By synthesizing emerging therapeutic targets and innovative technologies concerning TME, this review aims to provide novel insights that could enhance treatment outcomes for cancer patients.

Identification of gasdermin B function in the progression of renal clear cell carcinoma by a pan-cancer analysis

The Gasdermin (GSDM) protein family is critically involved in pyroptosis, which participates in the onset and progression of human malignancies. The exact role and impact of the GSDM family genes in various malignancies, particularly renal clear cell carcinoma (KIRC), is still uncertain. The present results indicated GSDMB gene expression significantly upregulated in individuals with KIRC, whose diagnostic effectiveness was confirmed through ROC analysis. Kaplan-Meier analysis also revealed KIRC patients had poor survival prognosis. The high expression of GSDMB served as an independent risk factor for overall survival (OS) in KIRC, based on multivariate cox analysis for confirmation. A nomogram based on GSDMB expression and clinical characteristics displayed remarkable diagnostic effectiveness for KIRC. Collectively, these findings may shed light on functions of GSDM family genes in tumor progression and offer new directions for future research into their potential as therapeutic targets in various types of tumors. Furthermore, the outcomes of this research highlighted that the prediction of treatment responses in KIRC patients may get improved through in-depth exploration into the impact of GSDMB expression on individuals with KIRC patients.

Pyroptosis: Induction and inhibition strategies for immunotherapy of diseases

Cell death is a central process for organismal health. Pyroptosis, namely pyroptotic cell death, is recognized as a critical type that disrupts membrane and triggers pro-inflammatory cytokine secretion via gasdermins, providing a robust form of cytolysis. Meanwhile, along with the thorough research, a great deal of evidence has demonstrated the dual effects of pyroptosis in host defense and inflammatory diseases. More importantly, the recent identification of abundant gasdermin-like proteins in bacteria and fungi suggests an ancient origin of pyroptosis-based regulated cell death in the life evolution. In this review, we bring a general overview of pyroptosis pathways focusing on gasdermin structural biology, regulatory mechanisms, and recent progress in induction and inhibition strategies for disease treatment. We look forward to providing an insightful perspective for readers to comprehend the frame and challenges of the pyroptosis field, and to accelerating its clinical application.

Gasdermins: a dual role in pyroptosis and tumor immunity

The gasdermin (GSDM) protein family plays a pivotal role in pyroptosis, a process critical to the body's immune response, particularly in combatting bacterial infections, impeding tumor invasion, and contributing to the pathogenesis of various inflammatory diseases. These proteins are adept at activating inflammasome signaling pathways, recruiting immune effector cells, creating an inflammatory immune microenvironment, and initiating pyroptosis. This article serves as an introduction to the GSDM protein-mediated pyroptosis signaling pathways, providing an overview of GSDMs' involvement in tumor immunity. Additionally, we explore the potential applications of GSDMs in both innovative and established antitumor strategies.

Prognostic, immunity, stemness, and anticancer drug sensitivity characterization of pyroptosis related genes in non-small cell lung cancer

BACKGROUND

Pyroptosis plays a pivotal role in the tumor immune microenvironment (TME) dynamics, particularly in non-small cell lung cancer (NSCLC). The aim of our study was to explore its effects on tumor progression, TME patterns, and the efficacy of therapeutic interventions in NSCLC.

METHODS

Our investigation encompassed a thorough analysis of pyroptosis-related genes (PRGs), integrating immunohistochemistry (IHC) data, TME characteristics, stemness indices, and anticancer drug sensitivities. We aimed to analyze mRNA expression profiles across various cancers, constructing benchmark datasets to assess the clinical significance of PRGs in NSCLC. This included evaluating their association with clinical responses and efficacy. Notably, both our and HPA IHC data demonstrated significantly elevated GSDMD-N protein levels in lung squamous cell carcinoma (LUSC) tissues.

RESULTS

The expression of PRGs differed significantly between tumor and normal tissues across various cancers, as validated by IHC data, and was correlated with prognosis (p < 0.05). Moreover, our investigation revealed significant differences (p < 0.05) in the expression of the PRGs among distinct TME subtypes categorized as C1 (wound healing), C3 (inflammatory), C2 (IFN-gamma dominant), C5 (immunological quiet), C4 (lymphocyte deficient), and C6 (TGF-beta dominant). Additionally, our research on anticancer drug sensitivity uncovered compelling connections between specific anticancer medications and the expression of PRGs, including GSDMD, ELANE, IL18, and CHMP4A (p < 0.05).

CONCLUSION

Our study provided valuable insights into the critical role of PRGs in TME modulation, tumor stemness, and anticancer drug sensitivity across diverse cancers. Our findings illuminate the intricate relationship between pyroptosis and the TME, offering new perspectives for enhancing NSCLC treatment and prognosis.

Current evidence and therapeutic implication of PANoptosis in cancer

Regulated cell death (RCD) is considered a critical pathway in cancer therapy, contributing to eliminating cancer cells and influencing treatment outcomes. The application of RCD in cancer treatment is marked by its potential in targeted therapy and immunotherapy. As a type of RCD, PANoptosis has emerged as a unique form of programmed cell death (PCD) characterized by features of pyroptosis, apoptosis, and necroptosis but cannot be fully explained by any of these pathways alone. It is regulated by a multi-protein complex called the PANoptosome. As a relatively new concept first described in 2019, PANoptosis has been shown to play a role in many diseases, including cancer, infection, and inflammation. This study reviews the application of PCD in cancer, particularly the emergence and implication of PANoptosis in developing therapeutic strategies for cancer. Studies have shown that the characterization of PANoptosis patterns in cancer can predict survival and response to immunotherapy and chemotherapy, highlighting the potential for PANoptosis to be used as a therapeutic target in cancer treatment. It also plays a role in limiting the spread of cancer cells. PANoptosis allows for the elimination of cancer cells by multiple cell death pathways and has the potential to address various challenges in cancer treatment, including drug resistance and immune evasion. Moreover, active investigation of the mechanisms and potential therapeutic agents that can induce PANoptosis in cancer cells is likely to yield effective cancer treatments and improve patient outcomes. Research on PANoptosis is still ongoing, but it is a rapidly evolving field with the potential to lead to new treatments for various diseases, including cancer.

A seven-immune-genes risk model predicts the survival and suitable treatments for patients with skin cutaneous melanoma

Background

Skin cutaneous melanoma is characterized by high malignancy and prognostic heterogeneity. Immune cell networks are critical to the biological progression of melanoma through the tumor microenvironment. Thus, identifying effective biomarkers for skin cutaneous melanoma from the perspective of the tumor microenvironment may offer strategies for precise prognosis prediction and treatment selection.

Methods

A total of 470 cases from The Cancer Genome Atlas and 214 from the Gene Expression Omnibus were systematically evaluated to construct an optimal independent immune cell risk model with predictive value using weighted gene co-expression network analysis, Cox regression, and least absolute shrinkage and selection operator assay. The predictive power of the developed model was estimated through receiver operating characteristic curves and Kaplan-Meier analysis. The association of the model with tumor microenvironment status, immune checkpoints, and mutation burden was assessed using multiple algorithms. Additionally, the sensitivity of immune and chemotherapeutics was evaluated using the ImmunophenScore and pRRophetic algorithm. Furthermore, the expression profiles of risk genes were validated using gene expression profiling interactive analysis and Human Protein Atlas resources.

Results

The risk model integrated seven immune-related genes: ARNTL, N4BP2L1, PARP11, NUB1, GSDMD, HAPLN3, and IRX3. The model demonstrated considerable predictive ability and was positively associated with clinical and molecular characteristics. It can be utilized as a prognostic factor for skin cutaneous melanoma, where a high-risk score was linked to a poor prognosis and indicated an immunosuppressive microenvironment. Furthermore, the model revealed several potential target checkpoints and predicted the therapeutic benefits of multiple clinically used drugs.

Conclusion

Our findings provide a comprehensive landscape of the tumor immune microenvironment in skin cutaneous melanoma and identify prognostic markers that may serve as efficient clinical diagnosis and treatment selection tools.

Role of gasdermin family proteins in cancers (Review)

The gasdermin (GSDM) family comprises six proteins, including GSDMA‑GSDME and Pejvakin. Most of these proteins have a crucial role in inducing pyroptosis; in particular, GSDMD and GSDME are the most extensively studied proteins as the executioners of the pyroptosis process. Pyroptosis is a highly pro‑inflammatory form of programmed cell death and is closely associated with the incidence, development and prognosis of multiple cancer types. The present review focused on the current knowledge of the molecular mechanism of GSDM‑mediated pyroptosis, its intricate role in cancer and the potential therapeutic value of its anti‑tumor effects.

Regulation of gasdermins in pyroptosis and cytokine release

Gasdermins are effectors of pyroptosis downstream of diverse signaling pathways. Emerging evidence suggests that a number of post-translational modifications regulate the function of gasdermins in pyroptosis, a highly inflammatory form of cell death, and lytic or non-lytic secretion of intracellular contents. These include processing by different caspases and other proteases that may activate or suppress pyroptosis, ubiquitination by a bacterial E3 ligase that suppresses pyroptosis as an immune evasion mechanism, modifications at Cys residues in mammalian or microbial gasdermins that promote or inhibit pyroptosis, and potential phosphorylation that represses pyroptosis. Such diverse regulatory mechanisms by host and microbial proteases, ubiquitin ligases, acyltransferases, kinases and phosphatases may underlie the divergent physiological and pathological functions of gasdermins, and furnish opportunities for therapeutic targeting of gasdermins in infectious diseases and inflammatory disorders.

Inflammasome and pyroptosis in autoimmune liver diseases

Autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and IgG4-related sclerosing cholangitis (IgG4-SC) are the four main forms of autoimmune liver diseases (AILDs), which are all defined by an aberrant immune system attack on the liver. Most previous studies have shown that apoptosis and necrosis are the two major modes of hepatocyte death in AILDs. Recent studies have reported that inflammasome-mediated pyroptosis is critical for the inflammatory response and severity of liver injury in AILDs. This review summarizes our present understanding of inflammasome activation and function, as well as the connections among inflammasomes, pyroptosis, and AILDs, thus highlighting the shared features across the four disease models and gaps in our knowledge. In addition, we summarize the correlation among NLRP3 inflammasome activation in the liver-gut axis, liver injury, and intestinal barrier disruption in PBC and PSC. We summarize the differences in microbial and metabolic characteristics between PSC and IgG4-SC, and highlight the uniqueness of IgG4-SC. We explore the different roles of NLRP3 in acute and chronic cholestatic liver injury, as well as the complex and controversial crosstalk between various types of cell death in AILDs. We also discuss the most up-to-date developments in inflammasome- and pyroptosis-targeted medicines for autoimmune liver disorders.