Targeting of GSDMD sensitizes HCC to anti-PD-1 by activating cGAS pathway and downregulating PD-L1 expression

Sodium butyrate increases USP5-mediated ubiquitination degradation of GPX4 and enhances anti-cancer efficacy of anti-PD-1 antibody

Hepatocellular carcinoma (HCC), a prevalent malignancy associated with a dismal prognosis, necessitates the urgent exploration of novel therapeutic avenues. Ferroptosis, an iron-mediated, lipid peroxidation-induced form of regulated cell death (RCD), has emerged as a promising target for cancer therapy. Sodium butyrate (NaBu), a short-chain fatty acid sodium salt, has demonstrated antitumor efficacy against diverse cancers, yet its specific role and mechanisms in HCC treatment remain elusive. Our findings reveal that NaBu not only impedes HCC cell growth and epithelial-mesenchymal transition (EMT) but also triggers ferroptosis by enhancing Fe2+ accumulation, reactive oxygen species (ROS) generation, and malondialdehyde (MDA) production. Notably, these effects are effectively mitigated by Ferrostatin-1 (Fer-1), underscoring the ferroptosis-inducing capacity of NaBu. Mechanistically, NaBu exerts its action by diminishing the level of ubiquitin-specific protease 5 (USP5), which subsequently leads to the ubiquitination and destabilization of glutathione peroxidase 4 (GPX4), a crucial suppressor in ferroptosis. In a preclinical setting, NaBu significantly inhibits tumor xenograft growth in nude mice, highlighting its in vivo efficacy. When paired with an anti-programmed death 1 (PD-1) antibody, NaBu exhibits a potent synergistic antitumor effect, suggesting a potential role in enhancing immunotherapy response. Collectively, our results underscore the potential of NaBu as a novel therapeutic agent for HCC, through its ability to inhibit USP5 and indirectly downregulate GPX4, thereby stimulating ferroptosis.

Deciphering cGAS-STING signaling: implications for tumor immunity and hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most prevalent form of primary liver cancer and poses a significant global health challenge due to its rising incidence and associated mortality. Recent advancements in understanding the cytosolic DNA sensing, the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway have illuminated its critical role in the immune response to HCC. This narrative review deciphers the multifaceted involvement of cGAS-STING in HCC, mainly its function in detecting cytosolic DNA and initiating type I interferon (IFN-I) responses, which are pivotal for antitumor immunity. This immune response is crucial for combating pathogens and can play a role in tumor surveillance. In the context of HCC, the tumor microenvironment (TME) can exhibit immune resistance, which complicates the effectiveness of therapies like immune checkpoint blockade. However, activation of the cGAS-STING pathway has been shown to stimulate antitumor immune responses, enhancing the activity of dendritic cells and cytotoxic T lymphocytes. There is ongoing research into STING agonists as a treatment strategy for HCC, with some studies indicating promising results in prolonging survival and enhancing the immune response against tumors. By summarizing current knowledge and identifying research gaps, this review aims to provide a comprehensive overview of cGAS-STING signaling in HCC and its future directions, emphasizing its potential as a therapeutic target in the fight against HCC. Understanding these mechanisms could pave the way for innovative immunotherapeutic approaches that enhance the efficacy of existing treatments and improve patient prognosis.

Targeting immune checkpoints in hepatocellular carcinoma therapy: toward combination strategies with curative potential

Hepatocellular carcinoma (HCC) is a primary liver cancer characterized by poor immune cell infiltration and a strongly immunosuppressive microenvironment. Traditional treatments have often yielded unsatisfactory outcomes due to the insidious onset of the disease. Encouragingly, the introduction of immune checkpoint inhibitors (ICIs) has significantly transformed the approach to HCC treatment. Moreover, combining ICIs with other therapies or novel materials is considered the most promising opportunity in HCC, with some of these combinations already being evaluated in large-scale clinical trials. Unfortunately, most clinical trials fail to meet their endpoints, and the few successful ones also face challenges. This indicates that the potential of ICIs in HCC treatment remains underutilized, prompting a reevaluation of this promising therapy. Therefore, this article provides a review of the role of immune checkpoints in cancer treatment, the research progress of ICIs and their combination application in the treatment of HCC, aiming to open up avenues for the development of safer and more efficient immune checkpoint-related strategies for HCC treatment.

Plasma protein levels and hepatocellular carcinoma: a Mendelian randomization study with drug screening implications

BACKGROUND

Hepatocellular carcinoma (HCC) remains a significant cause of cancer-related mortality, highlighting the need for novel therapeutic strategies. Identifying key proteins and potential therapeutic agents is critical for improving treatment outcomes.

METHODS

We employed Mendelian randomization to identify proteins associated with HCC risk and utilized drug enrichment and molecular docking analyses to discover potential therapeutic agents. The efficacy of identified drugs was evaluated in vitro using immune-tumor co-culture systems and in vivo in a murine HCC model. Single-cell expression profiling and clinical sample analyses were conducted to explore expression patterns.

RESULTS

Our analyses identified 16 proteins linked to HCC pathogenesis. Among the therapeutic agents tested, Belinostat significantly enhanced T cell-mediated cytotoxicity against HCC cells and effectively reduced tumor growth in vivo. Single-cell analysis revealed significant modulation of immune cells within the tumor microenvironment, suggesting potential mechanisms for the observed therapeutic effects.

CONCLUSION

This study highlights the potential of Belinostat as a promising therapeutic agent for HCC. By modulating immune responses and tumor growth, Belinostat offers a novel approach to HCC treatment, warranting further clinical investigation to validate its efficacy and therapeutic potential.

Role of inflammasomes in cancer immunity: mechanisms and therapeutic potential

Inflammasomes are multi-protein complexes that detect pathogenic and damage-associated molecular patterns, activating caspase-1, pyroptosis, and the maturation of pro-inflammatory cytokines such as IL-1β and IL-18Within the tumor microenvironment, inflammasomes like NLRP3 play critical roles in cancer initiation, promotion, and progression. Their activation influences the crosstalk between innate and adaptive immunity by modulating immune cell recruitment, cytokine secretion, and T-cell differentiation. While inflammasomes can contribute to tumor growth and metastasis through chronic inflammation, their components also present novel therapeutic targets. Several inhibitors targeting inflammasome components- such as sensor proteins (e.g., NLRP3, AIM2), adaptor proteins (e.g., ASC), caspase-1, and downstream cytokines- are being explored to modulate inflammasome activity. These therapeutic strategies aim to modulate inflammasome activity to enhance anti-tumor immune responses and improve clinical outcomes. Understanding the role of inflammasomes in cancer immunity is crucial for developing interventions that effectively bridge innate and adaptive immune responses for better therapeutic outcomes.

Autophagy in tumor immune escape and immunotherapy

The immunotherapy targeting tumor immune escape mechanisms has become a critical strategy in anticancer treatment; however, the challenge of immune resistance remains significant. Autophagy, a cellular response to various stressors, involves the degradation of damaged proteins and organelles via lysosomal pathways, maintaining cellular homeostasis. This process not only supports tumor cell survival but also profoundly impacts the efficacy of cancer immunotherapies. The modulation of autophagy in tumor cells or immune cells exerts dual effects on tumor immune escape and immunotherapy. However, the mechanistic details of how autophagy influences the immune system and therapy remain inadequately understood. Given this complexity, a deeper understanding of the role of autophagy in the tumor-immune landscape could reveal novel therapeutic avenues. By manipulating autophagy appropriately, it may be possible to overcome immune resistance and enhance the effectiveness of immunotherapeutic strategies. This article summarizes the role of autophagy in tumor immunity, its relationship with immunotherapy, and the potential therapeutic benefits of targeting autophagy to strengthen antitumor immune responses and optimize the outcomes of immunotherapy.

Sophisticated roles of tumor microenvironment in resistance to immune checkpoint blockade therapy in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) remains a serious threat to global health, with rising incidence and mortality rates. Therapeutic options for advanced HCC are quite limited, and the overall prognosis remains poor. Recent advancements in immunotherapy, particularly immune-checkpoint blockade (ICB) targeting anti-PD1/PD-L1 and anti-CTLA4, have facilitated a paradigm shift in cancer treatment, demonstrating substantial survival benefits across various cancer types, including HCC. However, only a subset of HCC patients exhibit a favorable response to ICB therapy, and its efficacy is often hindered by the development of resistance. There are many studies to explore the underlying mechanisms of ICB response. In this review, we compiled the latest progression in immunotherapies for HCC and systematically summarized the sophisticated mechanisms by which components of the tumor microenvironment (TME) regulate resistance to ICB therapy. Additionally, we also outlined some scientific rationale strategies to boost antitumor immunity and enhance the efficacy of ICB in HCC. These insights may serve as a roadmap for future research and help improve outcomes for HCC patients.

GSDMD-mediated pyroptosis: molecular mechanisms, diseases and therapeutic targets

Pyroptosis is a regulated form of inflammatory cell death in which Gasdermin D (GSDMD) plays a central role as the key effector molecule. GSDMD-mediated pyroptosis is characterized by complex biological features and considerable heterogeneity in its expression, mechanisms, and functional outcomes across various tissues, cell types, and pathological microenvironments. This heterogeneity is particularly pronounced in inflammation-related diseases and tumors. In the context of inflammatory diseases, GSDMD expression is typically upregulated, and its activation in macrophages, neutrophils, T cells, epithelial cells, and mitochondria triggers both pyroptotic and non-pyroptotic pathways, leading to the release of pro-inflammatory cytokines and exacerbation of tissue damage. However, under certain conditions, GSDMD-mediated pyroptosis may also serve a protective immune function. The expression of GSDMD in tumors is regulated in a more complex manner, where it can either promote immune evasion or, in some instances, induce tumor cell death. As our understanding of GSDMD's role continues to progress, there have been advancements in the development of inhibitors targeting GSDMD-mediated pyroptosis; however, these therapeutic interventions remain in the preclinical phase. This review systematically examines the cellular and molecular complexities of GSDMD-mediated pyroptosis, with a particular emphasis on its roles in inflammation-related diseases and cancer. Furthermore, it underscores the substantial therapeutic potential of GSDMD as a target for precision medicine, highlighting its promising clinical applications.

Bidirectional regulation of the cyclic guanosine monophosphate-adenosine monophosphate synthase-stimulator of interferon gene pathway and its impact on hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) ranks as the fourth leading cause of cancer-related deaths in China, and the treatment options are limited. The cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) activates the stimulator of interferon gene (STING) signaling pathway as a crucial immune response pathway in the cytoplasm, which detects cytoplasmic DNA to regulate innate and adaptive immune responses. As a potential therapeutic target, cGAS-STING pathway markedly inhibits tumor cell proliferation and metastasis, with its activation being particularly relevant in HCC. However, prolonged pathway activation may lead to an immunosuppressive tumor microenvironment, which fostering the invasion or metastasis of liver tumor cells.

AIM

To investigate the dual-regulation mechanism of cGAS-STING in HCC.

METHODS

This review was conducted according to the PRISMA guidelines. The study conducted a comprehensive search for articles related to HCC on PubMed and Web of Science databases. Through rigorous screening and meticulous analysis of the retrieved literature, the research aimed to summarize and elucidate the impact of the cGAS-STING pathway on HCC tumors.

RESULTS

All authors collaboratively selected studies for inclusion, extracted data, and the initial search of online databases yielded 1445 studies. After removing duplicates, the remaining 964 records were screened. Ultimately, 55 articles met the inclusion criteria and were included in this review.

CONCLUSION

Acute inflammation can have a few inhibitory effects on cancer, while chronic inflammation generally promotes its progression. Extended cGAS-STING pathway activation will result in a suppressive tumor microenvironment.

Gasdermin D regulates the activation of EGFR in colorectal cancer

BACKGROUND

Gasdermin D (GSDMD) is a key effector molecule that activates pyroptosis through its N terminal domain (GSDMD-NT). However, the roles of GSDMD in colorectal cancer (CRC) have not been fully explored. The role of the full-length GSDMD (GSDMD-FL) is also not clear. In this study, we observed that GSDMD modulates CRC progression through other mechanisms in addition to activating GSDMD-NT.

METHODS

Clinical CRC samples and human-derived CRC cell lines were used in this study. GSDMD expression was evaluated by RT-qPCR, Western blot and immunohistochemical (IHC) analysis. GSDMD knockdown and overexpression stable cell lines were established by Lentiviral transduction. CCK-8 assay, flow cytometry analysis for cell cycle, Transwell assay, and cell scratch assay were performed in vitro to explore the impact of GSDMD on CRC progression. Mouse subcutaneous transplantation tumor models were constructed to assess the role of GSDMD in vivo. Intestinal epithelial cell (IEC)-specific knockout of Gsdmd mice (GsdmdΔIEC) was used to evaluate the effect of GSDMD on intestinal adenoma formation in AOM-DSS and Apcmin/+ mouse models. RNA sequencing was performed to explore the regulatory pathways associated with the role of GSDMD in CRC cells. Co-Immunoprecipitation (CO-IP), Western blot and immunofluorescence (IF) were conducted to investigate the interactions between GSDMD and EGFR. Exogenous addition of Gefitinib was used to evaluate the effect of GSDMD on autophosphorylation of EGFR at the Tyr1068 site.

RESULTS

GSDMD was highly expressed in clinical CRC tissues and human-derived CRC cell lines. GSDMD knockdown inhibited the viability, cell cycle changes, invasion ability and migration ability of CRC cell lines in vitro and vivo, whereas GSDMD overexpression had the opposite effects. Intestinal adenoma development was reduced in GsdmdΔIEC mice in both AOM-DSS and Apcmin/+ mouse models. GSDMD-FL interacted with EGFR and promoted CRC progression by inducing autophosphorylation of EGFR at the Tyr1068 site, subsequently activating ERK1/2. Exogenous Gefitinib abrogated the tumorigenic properties of GSDMD.

CONCLUSIONS

GSDMD-FL promotes CRC progression by inducing EGFR autophosphorylation at the Tyr1068 site, subsequently activating the downstream ERK1/2. Inhibition of GSDMD is a potential strategy for the treatment of colorectal cancer.

CYB561 a potential prognostic biomarker for liver hepatocellular carcinoma

Liver hepatocellular carcinoma (LIHC) is a malignancy characterized by a high rate of recurrence, metastasis, and poor prognosis. Cytochrome b561 (CYB561) has been previously reported to be associated with tumor progression, but it has not been revealed in LIHC. The aim of this study was to investigate the prognostic value and potential function of CYB561 in LICH. The expression level, clinical correlation, prognosis, and biological function of CYB561 in LIHC were analyzed using The Cancer Genome Atlas（TCGA), Gene Expression Omnibus (GEO), TIMER2, Kaplan-Meier Plotter, and GEPIA2 databases. The expression of CYB561 in LIHC tissue samples was analyzed by immunohistochemical staining. The effect of CYB561 on the proliferation and migration of LIHC cells was investigated by using CYB561 knockdown in vitro. GSE149614 dataset was used to analyze the expression distribution of CYB561 in LIHC on a single-cell dimension. This study showed that CYB561 mRNA and protein were highly expressed in LIHC. High expression of CYB561 suggests poor prognosis in LICH patients and is an independent risk factor for LIHC. Wound-healing experiment, transwell experiment, and clonal formation experiment confirmed that CYB561 knockdown could inhibit the proliferation and migration of LIHC cells. Functional enrichment analysis showed that CYB561 was related to biological processes such as cell adhesion and immune response. KEGG enrichment analysis showed that CYB561 interacts with tumor-related signaling pathways. Single-cell analysis showed that CYB561 was mainly expressed in hepatocytes. Cells with high CYB561 expression had a higher degree of malignancy. Our study found that abnormal expression of CYB561 in LIHC suggested poor prognosis of LIHC and was related to tumor migration and proliferation. CYB561 is a potential prognostic predictor or therapeutic biomarker.

The role of pyroptosis in cancer: key components and therapeutic potential

Pyroptosis is a lytic and inflammatory form of gasdermin protein-mediated programmed cell death that is typically initiated by inflammasomes. The inflammasome response is an effective mechanism for eradicating germs and cancer cells in the event of cellular injury. The gasdermin family is responsible for initiating pyroptosis, a process in which holes are made in the cell membrane to allow inflammatory chemicals to escape. Mounting evidence indicates that pyroptosis is critical for controlling the development of cancer. In this review, we provide a general overview of pyroptosis, examine the relationship between the primary elements of pyroptosis and tumors, and stress the necessity of pyroptosis-targeted therapy in tumors. Furthermore, we explore its dual nature as a double-edged sword capable of both inhibiting and facilitating the growth of cancer, depending on the specific conditions. Ultimately, pyroptosis is a phenomenon that has both positive and negative effects on tumors. Using this dual impact in a reasonable manner may facilitate investigation into the initiation and progression of tumors and offer insights for the development of novel treatments centered on pyroptosis.

Cinobufotalin inhibits proliferation, migration and invasion in hepatocellular carcinoma by triggering NOX4/NLRP3/GSDMD-dependent pyroptosis

Introduction

Pyroptosis is an inflammatory form of programmed cell death that plays a significant role in tumorigenesis. Cinobufotalin (CB), a bufadienolide extracted from toad venom, is associated with antitumor effects in various cancers, including liver cancer. However, the role of CB in pyroptosis and its underlying mechanisms have not been well characterized.

Methods

MTT, Colony formation, EdU, Wound healing and Transwell migration and invasion assays were applied to determine the effects of CB on the proliferation, migration, and invasion ability of hepatocellular carcinoma (HCC) cells in vitro. The subcutaneous xenograft mouse model and pulmonary metastasis model were used to evaluate the effect of CB on HCC cells in vivo. PCR, western blot, immunohistochemistry, immunofluorescence, and ELISA were used to verify the expression of proliferation, migration, pyroptosis, and inflammation related molecules after CB treatment. Using si-RNA and inhibitors to interfere with NOX4 and HLRP3 expression to validate the key signaling pathways of pyroptosis induced by CB treatment.

Results

In vivo experiments using nude mice with xenografted HCC cells and in vitro experiments with HCC cell lines demonstrated that CB treatment significantly inhibited the proliferation, migration, and invasiveness of HCC cells. CB treatment also showed dose-dependent activation of the NLRP3 inflammasome complex in HCC cells, leading to gasdermin D-induced pyroptosis. However, these effects were abrogated via the pretreatment of HCC cells with VX-765, a caspase-1 inhibitor. Additionally, CB increased the production of reactive oxygen species (ROS) and H₂O₂, along with upregulating NOX4 protein expression in HCC cells. Conversely, NOX4 silencing or pretreatment with VAS2870 (an NOX4 inhibitor) or NAC (an ROS scavenger) suppressed the activation of the NLRP3 inflammasome complex and pyroptosis in CB-treated HCC cells.

Discussion

Our study demonstrated that CB suppressed the proliferation, migration, and invasiveness of HCC cells by inducing pyroptosis through the activation of the NOX4/NLRP3/GSDMD signaling pathway. Therefore, our results suggest that CB is a promising therapeutic agent for HCC.

Igniting hope: Harnessing NLRP3 inflammasome-GSDMD-mediated pyroptosis for cancer immunotherapy

In the contemporary landscape of oncology, immunotherapy, represented by immune checkpoint blockade (ICB) therapy, stands out as a beacon of innovation in cancer treatment. Despite its promise, the therapy's progression is hindered by suboptimal clinical response rates. Addressing this challenge, the modulation of the NLRP3 inflammasome-GSDMD-mediated pyroptosis pathway holds promise as a means to augment the efficacy of immunotherapy. In the pathway, the NLRP3 inflammasome serves as a pivotal molecular sensor that responds to inflammatory stimuli within the organism. Its activation leads to the release of cytokines interleukin 1β and interleukin 18 through the cleavage of GSDMD, thereby forming membrane pores and potentially resulting in pyroptosis. This cascade of processes exerts a profound impact on tumor development and progression, with its function and expression exhibiting variability across different tumor types and developmental stages. Consequently, understanding the specific roles of the NLRP3 inflammasome and GSDMD-mediated pyroptosis in diverse tumors is imperative for comprehending tumorigenesis and crafting precise therapeutic strategies. This review aims to elucidate the structure and activation mechanisms of the NLRP3 inflammasome, as well as the induction mechanisms of GSDMD-mediated pyroptosis. Additionally, we provide a comprehensive overview of the involvement of this pathway in various cancer types and its applications in tumor immunotherapy, nanotherapy, and other fields. Emphasis is placed on the feasibility of leveraging this approach to enhance ICB therapy within the field of immunotherapy. Furthermore, we discuss the potential applications of this pathway in other immunotherapy methods, such as chimeric antigen receptor T-cell (CAR-T) therapy and tumor vaccines.

A Novel Bioluminescent Biosensor Quantifying Intramolecular Interaction and Levels of Pyroptosis Effector GSDMD

Gasdermin D (GSDMD) is a key executor of pyroptosis, a form of inflammation-induced programmed cell death. Recently, GSDMD has been shown to play important roles in the development of various inflammatory-related human diseases including heart failure and cancer, suggesting that it is a promising therapeutic target for these diseases. While extensive studies on GSDMD's role in pyroptosis have been reported, it is challenging to study its function due to the lack of enzymatic activity of GSDMD. In this study, we used the NanoBiT technology to develop a novel GSDMD bioluminescent biosensor (GSDMD-BS) that detects the amount of non-cleaved GSDMD. This sensor allows us to quantify GSDMD's intramolecular interactions, the amounts of uncleaved GSDMD after caspase-1 cleavage, and expression levels in living cells. In vitro experiments using purified GSDMD-BS also confirmed the sensor's accuracy in reporting GSDMD levels and cleavage. Moreover, the potential for in vivo application was demonstrated in a xenograft mouse model. In conclusion, we have developed a GSDMD biosensor that is a valuable tool for real-time monitoring of GSDMD dynamics and pyroptosis. This biosensor will significantly expedite pyroptosis research and can be used for high-throughput screening for drugs targeting GSDMD for the therapy of many inflammation-related diseases.

Role of gasdermin D in inflammatory diseases: from mechanism to therapeutics

Inflammatory diseases compromise a clinically common and diverse group of conditions, causing detrimental effects on body functions. Gasdermins (GSDM) are pore-forming proteins, playing pivotal roles in modulating inflammation. Belonging to the GSDM family, gasdermin D (GSDMD) actively mediates the pathogenesis of inflammatory diseases by mechanistically regulating different forms of cell death, particularly pyroptosis, and cytokine release, in an inflammasome-dependent manner. Aberrant activation of GSDMD in different types of cells, such as immune cells, cardiovascular cells, pancreatic cells and hepatocytes, critically contributes to the persistent inflammation in different tissues and organs. The contributory role of GSDMD has been implicated in diabetes mellitus, liver diseases, cardiovascular diseases, neurodegenerative diseases, and inflammatory bowel disease (IBD). Clinically, alterations in GSDMD levels are potentially indicative to the occurrence and severity of diseases. GSDMD inhibition might represent an attractive therapeutic direction to counteract the progression of inflammatory diseases, whereas a number of GSDMD inhibitors have been shown to restrain GSDMD-mediated pyroptosis through different mechanisms. This review discusses the current understanding and future perspectives on the role of GSDMD in the development of inflammatory diseases, as well as the clinical insights of GSDMD alterations, and therapeutic potential of GSDMD inhibitors against inflammatory diseases. Further investigation on the comprehensive role of GSDM shall deepen our understanding towards inflammation, opening up more diagnostic and therapeutic opportunities against inflammatory diseases.

GSDMD is associated with survival in human breast cancer but does not impact anti-tumor immunity in a mouse breast cancer model

Inflammation plays a pivotal role in cancer development, with chronic inflammation promoting tumor progression and treatment resistance, whereas acute inflammatory responses contribute to protective anti-tumor immunity. Gasdermin D (GSDMD) mediates the release of pro-inflammatory cytokines such as IL-1β. While the release of IL-1β is directly linked to the progression of several types of cancers, the role of GSDMD in cancer is less clear. In this study, we show that GSDMD expression is upregulated in human breast, kidney, liver, and prostate cancer. Higher GSDMD expression correlated with increased survival in primary breast invasive carcinoma (BRCA), but not in liver hepatocellular carcinoma (LIHC). In BRCA, but not in LIHC, high GSDMD expression correlated with a myeloid cell signature associated with improved prognosis. To further investigate the role of GSDMD in anticancer immunity, we induced breast cancer and hepatoma tumors in GSDMD-deficient mice. Contrary to our expectations, GSDMD deficiency had no effect on tumor growth, immune cell infiltration, or cytokine expression in the tumor microenvironment, except for Cxcl10 upregulation in hepatoma tumors. In vitro and in vivo innate immune activation with TLR ligands, that prime inflammatory responses, revealed no significant difference between GSDMD-deficient and wild-type mice. These results suggest that the impact of GSDMD on anticancer immunity is dependent on the tumor type. They underscore the complex role of inflammatory pathways in cancer, emphasizing the need for further exploration into the multifaceted effects of GSDMD in various tumor microenvironments. As several pharmacological modulators of GSDMD are available, this may lead to novel strategies for combination therapy in cancer.

Burning down the house: Pyroptosis in the tumor microenvironment of hepatocellular carcinoma

A high mortality rate makes hepatocellular carcinoma (HCC) a difficult cancer to treat. When surgery is not possible, liver cancer patients are treated with chemotherapy. However, HCC management and treatment are difficult. Sorafenib, which is a first-line treatment for hepatocellular carcinoma, initially slows disease progression. However, sorafenib resistance limits patient survival. Recent studies have linked HCC to programmed cell death, which has increased researcher interest in therapies targeting cell death. Pyroptosis, which is an inflammatory mode of programmed cell death, may be targeted to treat HCC. Pyroptosis pathways, executors, and effects are examined in this paper. This review summarizes how pyroptosis affects the tumor microenvironment (TME) in HCC, including the role of cytokines such as IL-1β and IL-18 in regulating immune responses. The use of chemotherapies and their ability to induce cancer cell pyroptosis as alternative treatments and combining them with other drugs to reduce side effects is also discussed. In conclusion, we highlight the potential of inducing pyroptosis to treat HCC and suggest ways to improve patient outcomes. Studies on cancer cell pyroptosis may lead to new HCC treatments.

Trimethyl chitosan-cysteine-based nanoparticles as an effective delivery system for portulacerebroside A in the management of hepatocellular carcinoma cells in vitro and in vivo

Portulacerebroside A (PCA), a cerebroside compound extracted from Portulaca oleracea L., has been shown to suppress hepatocellular carcinoma (HCC) cells. This study aims to investigate the effectiveness of trimethyl chitosan-cysteine (TMC-Cys) nanocarrier in delivering PCA for HCC management and to elucidate the molecular mechanisms behind PCA's function. TMC-Cys nanocarriers notably augmented PCA's function, diminishing the proliferation, migration, and invasiveness of HCC cells in vitro, reducing hepatocellular tumorigenesis in immunocompetent mice, and impeding metastasis of xenograft tumours in nude mice. Comprehensive bioinformatics analyses, incorporating Super-PRED systems alongside pathway enrichment analysis, pinpointed toll-like receptor 4 (TLR4) and epidermal growth factor receptor (EGFR) as two promising targets of PCA, enriched in immune checkpoint pathway. PCA/nanocarrier (PCA) reduced levels of TLR4 and EGFR and their downstream proteins, including programmed cell death ligand 1, thereby increasing populations and activity of T cells co-cultured with HCC cells in vitro or in primary HCC tumours in mice. However, these effects were counteracted by additional artificial activation of TLR4 and EGFR. In conclusion, this study provides novel evidence of PCA's function in immunomodulation in addition to its direct tumour suppressive effect. TMC-Cys nanocarriers significantly enhance PCA efficacy, indicating promising application as a drug delivery system.

The role of PD-1/PD-L1 signaling pathway in cancer pathogenesis and treatment: a systematic review

Aim: Cancer as a complex disease poses significant challenges for both diagnosis and treatment. Researchers have been exploring various avenues to find effective therapeutic strategies, with a particular emphasis on cellular signaling pathways and immunotherapy. One such pathway that has recently been suggested is the PD-1/PD-L1 pathway, which is an immune checkpoint signaling system that plays an important role in regulating the immune system and maintaining tissue homeostasis. Cancer cells exploit this pathway by producing PD-L1, which attaches to PD-1 on T cells, thus inhibiting immune responses and enabling the cancer cells to escape detection by the immune system. This study aimed to evaluate the role of the PD-1/PD-L1 pathway in cancer pathogenesis and treatment. Method: This study was performed based on the principles of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). All in vitro , in vivo , and clinical studies that were published in English have been considered during a thorough search of the Scopus, Web of Science, and PubMed databases without date restriction until March 2024. Results: According to the studies reviewed, the PD-1/PD-L1 signaling axis suggests promising therapeutic effects on various types of cancers such as non-small cell lung cancer, melanoma, breast cancer, hepatocellular carcinoma, squamous cell carcinoma, and colorectal cancer, among others. Additionally, research suggests that immune checkpoint inhibitors that block PD1/PD-L1, such as pembrolizumab, atezolizumab, nivolumab, durvalumab, cemiplimab, avelumab, etc. , can effectively prevent tumor cells from escaping the immune system. Moreover, there might be a possible interaction between microbiome, obesity, etc. on immune mechanisms and on the immune checkpoint inhibitors (ICIs). Conclusion: Although we have gained considerable knowledge about ICIs, we are still facing challenges in effectively prescribing the appropriate ICIs for individual patients. This is largely due to the complex interactions between different intracellular pathways, which need to be thoroughly studied. To resolve this issue, it is necessary to conduct more reliable clinical trials that can produce a scientific consensus.

The gasdermin family: emerging therapeutic targets in diseases

The gasdermin (GSDM) family has garnered significant attention for its pivotal role in immunity and disease as a key player in pyroptosis. This recently characterized class of pore-forming effector proteins is pivotal in orchestrating processes such as membrane permeabilization, pyroptosis, and the follow-up inflammatory response, which are crucial self-defense mechanisms against irritants and infections. GSDMs have been implicated in a range of diseases including, but not limited to, sepsis, viral infections, and cancer, either through involvement in pyroptosis or independently of this process. The regulation of GSDM-mediated pyroptosis is gaining recognition as a promising therapeutic strategy for the treatment of various diseases. Current strategies for inhibiting GSDMD primarily involve binding to GSDMD, blocking GSDMD cleavage or inhibiting GSDMD-N-terminal (NT) oligomerization, albeit with some off-target effects. In this review, we delve into the cutting-edge understanding of the interplay between GSDMs and pyroptosis, elucidate the activation mechanisms of GSDMs, explore their associations with a range of diseases, and discuss recent advancements and potential strategies for developing GSDMD inhibitors.

The role of inflammasomes in human diseases and their potential as therapeutic targets

Inflammasomes are large protein complexes that play a major role in sensing inflammatory signals and triggering the innate immune response. Each inflammasome complex has three major components: an upstream sensor molecule that is connected to a downstream effector protein such as caspase-1 through the adapter protein ASC. Inflammasome formation typically occurs in response to infectious agents or cellular damage. The active inflammasome then triggers caspase-1 activation, followed by the secretion of pro-inflammatory cytokines and pyroptotic cell death. Aberrant inflammasome activation and activity contribute to the development of diabetes, cancer, and several cardiovascular and neurodegenerative disorders. As a result, recent research has increasingly focused on investigating the mechanisms that regulate inflammasome assembly and activation, as well as the potential of targeting inflammasomes to treat various diseases. Multiple clinical trials are currently underway to evaluate the therapeutic potential of several distinct inflammasome-targeting therapies. Therefore, understanding how different inflammasomes contribute to disease pathology may have significant implications for developing novel therapeutic strategies. In this article, we provide a summary of the biological and pathological roles of inflammasomes in health and disease. We also highlight key evidence that suggests targeting inflammasomes could be a novel strategy for developing new disease-modifying therapies that may be effective in several conditions.

Interplay between inflammasomes and PD-1/PD-L1 and their implications in cancer immunotherapy

The inflammasomes play crucial roles in inflammation and cancer development, while the PD-1/PD-L1 pathway is critical for immune suppression in the tumor microenvironment (TME). Recent research indicates a reciprocal regulatory relationship between inflammasomes and PD-1/PD-L1 signaling in cancer development and PD-1 blockade treatment. By activating in diverse cells in tumor tissues, inflammasome upregulates PD-L1 level in the TME. Moreover, the regulation of PD-1/PD-L1 activity by inflammasome activation involves natural killer cells, tumor-associated macrophages and myeloid-derived suppressor cells. Conversely, PD-1 blockade can activate the inflammasome, potentially influencing treatment outcomes. The interplay between inflammasomes and PD-1/PD-L1 has profound and intricate effects on cancer development and treatment. In this review, we discuss the crosstalk between inflammasomes and PD-1/PD-L1 in cancers, exploring their implications for tumorigenesis, metastasis and immune checkpoint inhibitor (ICI) resistance. The combined therapeutic strategies targeting both inflammasomes and checkpoint molecules hold promising potential as treatments for cancer.

Mechanisms of PANoptosis and relevant small-molecule compounds for fighting diseases

Pyroptosis, apoptosis, and necroptosis are mainly programmed cell death (PCD) pathways for host defense and homeostasis. PANoptosis is a newly distinct inflammatory PCD pathway that is uniquely regulated by multifaceted PANoptosome complexes and highlights significant crosstalk and coordination among pyroptosis (P), apoptosis (A), and/or necroptosis(N). Although some studies have focused on the possible role of PANpoptosis in diseases, the pathogenesis of PANoptosis is complex and underestimated. Furthermore, the progress of PANoptosis and related agonists or inhibitors in disorders has not yet been thoroughly discussed. In this perspective, we provide perspectives on PANoptosome and PANoptosis in the context of diverse pathological conditions and human diseases. The treatment targeting on PANoptosis is also summarized. In conclusion, PANoptosis is involved in plenty of disorders including but not limited to microbial infections, cancers, acute lung injury/acute respiratory distress syndrome (ALI/ARDS), ischemia-reperfusion, and organic failure. PANoptosis seems to be a double-edged sword in diverse conditions, as PANoptosis induces a negative impact on treatment and prognosis in disorders like COVID-19 and ALI/ARDS, while PANoptosis provides host protection from HSV1 or Francisella novicida infection, and kills cancer cells and suppresses tumor growth in colorectal cancer, adrenocortical carcinoma, and other cancers. Compounds and endogenous molecules focused on PANoptosis are promising therapeutic strategies, which can act on PANoptosomes-associated members to regulate PANoptosis. More researches on PANoptosis are needed to better understand the pathology of human conditions and develop better treatment.

The current status and future of PD-L1 in liver cancer

The application of immunotherapy in tumor, especially immune checkpoint inhibitors (ICIs), has played an important role in the treatment of advanced unresectable liver cancer. However, the efficacy of ICIs varies greatly among different patients, which has aroused people's attention to the regulatory mechanism of programmed death ligand-1 (PD-L1) in the immune escape of liver cancer. PD-L1 is regulated by multiple levels and signaling pathways in hepatocellular carcinoma (HCC), including gene variation, epigenetic inheritance, transcriptional regulation, post-transcriptional regulation, and post-translational modification. More studies have also found that the high expression of PD-L1 may be the main factor affecting the immunotherapy of liver cancer. However, what is the difference of PD-L1 expressed by different types of cells in the microenvironment of HCC, and which type of cells expressed PD-L1 determines the effect of tumor immunotherapy remains unclear. Therefore, clarifying the regulatory mechanism of PD-L1 in liver cancer can provide more basis for liver cancer immunotherapy and combined immune treatment strategy. In addition to its well-known role in immune regulation, PD-L1 also plays a role in regulating cancer cell proliferation and promoting drug resistance of tumor cells, which will be reviewed in this paper. In addition, we also summarized the natural products and drugs that regulated the expression of PD-L1 in HCC.

The role of pyroptosis and gasdermin family in tumor progression and immune microenvironment

Pyroptosis, an inflammatory programmed cell death, distinguishes itself from apoptosis and necroptosis and has drawn increasing attention. Recent studies have revealed a correlation between the expression levels of many pyroptosis-related genes and both tumorigenesis and progression. Despite advancements in cancer treatments such as surgery, radiotherapy, chemotherapy, and immunotherapy, the persistent hallmark of cancer enables malignant cells to elude cell death and develop resistance to therapy. Recent findings indicate that pyroptosis can overcome apoptosis resistance amplify treatment-induced tumor cell death. Moreover, pyroptosis triggers antitumor immunity by releasing pro-inflammatory cytokines, augmenting macrophage phagocytosis, and activating cytotoxic T cells and natural killer cells. Additionally, it transforms "cold" tumors into "hot" tumors, thereby enhancing the antitumor effects of various treatments. Consequently, pyroptosis is intricately linked to tumor development and holds promise as an effective strategy for boosting therapeutic efficacy. As the principal executive protein of pyroptosis, the gasdermin family plays a pivotal role in influencing pyroptosis-associated outcomes in tumors and can serve as a regulatory target. This review provides a comprehensive summary of the relationship between pyroptosis and gasdermin family members, discusses their roles in tumor progression and the tumor immune microenvironment, and analyses the underlying therapeutic strategies for tumor treatment based on pyroptotic cell death.

Understanding nucleic acid sensing and its therapeutic applications

Nucleic acid sensing is involved in viral infections, immune response-related diseases, and therapeutics. Based on the composition of nucleic acids, nucleic acid sensors are defined as DNA or RNA sensors. Pathogen-associated nucleic acids are recognized by membrane-bound and intracellular receptors, known as pattern recognition receptors (PRRs), which induce innate immune-mediated antiviral responses. PRR activation is tightly regulated to eliminate infections and prevent abnormal or excessive immune responses. Nucleic acid sensing is an essential mechanism in tumor immunotherapy and gene therapies that target cancer and infectious diseases through genetically engineered immune cells or therapeutic nucleic acids. Nucleic acid sensing supports immune cells in priming desirable immune responses during tumor treatment. Recent studies have shown that nucleic acid sensing affects the efficiency of gene therapy by inhibiting translation. Suppression of innate immunity induced by nucleic acid sensing through small-molecule inhibitors, virus-derived proteins, and chemical modifications offers a potential therapeutic strategy. Herein, we review the mechanisms and regulation of nucleic acid sensing, specifically covering recent advances. Furthermore, we summarize and discuss recent research progress regarding the different effects of nucleic acid sensing on therapeutic efficacy. This study provides insights for the application of nucleic acid sensing in therapy.

The 'speck'-tacular oversight of the NLRP3-pyroptosis pathway on gastrointestinal inflammatory diseases and tumorigenesis

The NLRP3 inflammasome is an intracellular sensor and an essential component of the innate immune system involved in danger recognition. An important hallmark of inflammasome activation is the formation of a single supramolecular punctum, known as a speck, per cell, which is the site where the pro-inflammatory cytokines IL-1β and IL-18 are converted into their bioactive form. Speck also provides the platform for gasdermin D protein activation, whose N-terminus domain perforates the plasma membrane, allowing the release of mature cytokines alongside with a highly inflammatory form of cell death, namely pyroptosis. Although controlled NLRP3 inflammasome-pyroptosis pathway activation preserves mucosal immunity homeostasis and contributes to host defense, a prolonged trigger is deleterious and could lead, in genetically predisposed subjects, to the onset of inflammatory bowel disease, including Crohn's disease and ulcerative colitis, as well as to gastrointestinal cancer. Experimental evidence shows that the NLRP3 inflammasome has both protective and pathogenic abilities. In this review we highlight the impact of the NLRP3-pyroptosis axis on the pathophysiology of the gastrointestinal tract at molecular level, focusing on newly discovered features bearing pro- and anti-inflammatory and neoplastic activity, and on targeted therapies tested in preclinical and clinical trials.

Drug co-administration in the tumor immune microenvironment of Hepatocellular carcinoma

The etiology and exact molecular mechanisms of primary hepatocellular carcinoma (HCC) remain unclear, and its incidence has continued to increase in recent years. Despite tremendous advances in systemic therapies such as molecularly targeted drugs, HCC has some of the worst prognoses owing to drug resistance, frequent recurrence, and metastasis. Hepatocellular carcinoma is a widespread disease and its progression is regulated by the immune system. Traditional Chinese medicine (TCM) has been gradually theorized and systematized to have a holistic regulatory role for use in the prevention and treatment of tumors. Although half of the patients with HCC receive systemic therapy, traditionally sorafenib or lenvatinib are used as first-line treatment modalities. TCM is also widely used in the treatment of HCC, and the same immune checkpoint inhibitors (ICIs) such as PD-L1 have also received much focus in the field of continuously changing cancer treatment. Owing to the high probability of resistance to specific drugs and unsatisfactory efficacy due to administration of chemotherapy in single doses, the combination of drugs is the newest therapeutic option for patients with tumors and has become increasingly prominent for treatment. In this article, the research progress on combination therapy in the immunology of HCC is reviewed and the unique advantages of synergistic anti-tumor therapy with combination drugs are highlighted to provide new solutions for the clinical treatment of tumors.

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http://links.lww.com/AHM/A65

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.

The Pyroptotic and Nonpyroptotic Roles of Gasdermins in Modulating Cancer Progression and Their Perspectives on Cancer Therapeutics

Gasdermins (GSDMs) are a protein family encoded by six paralogous genes in humans, including GSDMA, GSDMB, GSDMC, GSDMD, GSDME (also known as DFNA5), and DFNB59 (also known as pejvakin). Structurally, members of the GSDM family possess a C-terminus (an autoinhibitory domain) and a positively charged N-terminus (a pore-forming domain) linked with divergent peptide linkers. Recently, GSDMs have been identified as key executors of pyroptosis (an immunogenic programmed cell death) due to their pore-forming activities on the plasma membrane when proteolytically cleaved by caspases or serine proteases. Accumulating studies suggest that chemoresistance is attributed to dysregulation of apoptotic machinery and that inducing pyroptosis to bypass aberrant apoptosis can potently resensitize apoptosis-resistant cancer to chemotherapeutics. Pyroptosis is initiated by pore formation and culminates with plasma membrane rupture; these processes enable the release of proinflammatory cytokines (e.g., IL-1β and IL-18) and damage-associated molecular patterns, which further modulate antitumor immunity within the tumor microenvironment. Although pyroptosis is considered a promising strategy to boost antitumor effects, it is also reported to cause unwanted tissue damage (e.g., gut damage and nephrotoxicity). Intriguingly, mounting evidence has uncovered nonpyroptotic roles of GSDMs in tumorigenesis, such as proliferation, invasion, metastasis, and drug resistance. Thus, this provides a rationale for GSDMs as potential therapeutic targets. Taken together, we shed unbiased light on the pyroptosis-dependent roles of GSDMs in cancer progression and highlighted how GSDMs modulate tumorigenesis in a pyroptosis-independent manner. It is evident that targeting GSDMs seems profound in cancer management; however, several problems require further investigation to target GSDMs from bench to bedside, which is elucidated in the discussion section.

Identification of PANoptosis-relevant subgroups to evaluate the prognosis and immune landscape of patients with liver hepatocellular carcinoma

Liver hepatocellular carcinoma (LIHC) is one of the most common malignant tumors, which is difficult to be diagnosed at an early stage due to its poor prognosis. Despite the fact that PANoptosis is important in the occurrence and development of tumors, no bioinformatic explanation related to PANoptosis in LIHC can be found. A bioinformatics analysis on the data of LIHC patients in TCGA database was carried out on the basis of previously identified PANoptosis-related genes (PRGs). LIHC patients were divided into two PRG clusters whose gene characteristics of differentially expressed genes (DEGs) were discussed. According to DEGs, the patients were further divided into two DEG clusters, and prognostic-related DEGs (PRDEGs) were applied to risk score calculation, the latter of which turned out to be practical in identifying the relationship among risk score, patient prognosis, and immune landscape. The results suggested that PRGs and relevant clusters were bound up with the survival and immunity of patients. Moreover, the prognostic value based on two PRDEGs was evaluated, the risk scoring model was constructed, and the nomogram model for predicting the survival rate of patients was further developed. Therefore, it was found that the prognosis of the high-risk subgroup was poor. Additionally, three factors, namely, the abundance of immune cells, the expression of immune checkpoints, and immunotherapy and chemotherapy were considered to be associated with the risk score. RT-qPCR results indicated higher positive expression of CD8A and CXCL6 in both LIHC tissues and most human liver cancer cell lines. In summary, the results suggested that PANoptosis was bound up with LIHC-related survival and immunity. Two PRDEGs were identified as potential markers. Thus, the understanding of PANoptosis in LIHC was enriched, with some strategies provided for the clinical therapy of LIHC.

The Role of TLR4 in the Immunotherapy of Hepatocellular Carcinoma: Can We Teach an Old Dog New Tricks?

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and is a leading cause of cancer-related death worldwide. Immunotherapy has emerged as the mainstay treatment option for unresectable HCC. Toll-like receptor 4 (TLR4) plays a crucial role in the innate immune response by recognizing and responding primarily to bacterial lipopolysaccharides. In addition to its role in the innate immune system, TLR4 has also been implicated in adaptive immunity, including specific anti-tumor immune responses. In particular, the TLR4 signaling pathway seems to be involved in the regulation of several cancer hallmarks, such as the continuous activation of cellular pathways that promote cell division and growth, the inhibition of programmed cell death, the promotion of several invasion and metastatic mechanisms, epithelial-to-mesenchymal transition, angiogenesis, drug resistance, and epigenetic modifications. Emerging evidence further suggests that TLR4 signaling holds promise as a potential immunotherapeutic target in HCC. The aim of this review was to explore the multilayer aspects of the TLR4 signaling pathway, regarding its role in liver diseases and HCC, as well as its potential utilization as an immunotherapy target for HCC.

The double sides of NLRP3 inflammasome activation in sepsis

Sepsis is defined as a life-threatening organ dysfunction induced by a dysregulated host immune response to infection. Immune response induced by sepsis is complex and dynamic. It is schematically described as an early dysregulated systemic inflammatory response leading to organ failures and early deaths, followed by the development of persistent immune alterations affecting both the innate and adaptive immune responses associated with increased risk of secondary infections, viral reactivations, and late mortality. In this review, we will focus on the role of NACHT, leucin-rich repeat and pyrin-containing protein 3 (NLRP3) inflammasome in the pathophysiology of sepsis. NLRP3 inflammasome is a multiproteic intracellular complex activated by infectious pathogens through a two-step process resulting in the release of the pro-inflammatory cytokines IL-1β and IL-18 and the formation of membrane pores by gasdermin D, inducing a pro-inflammatory form of cell death called pyroptosis. The role of NLRP3 inflammasome in the pathophysiology of sepsis can be ambivalent. Indeed, although it might protect against sepsis when moderately activated after initial infection, excessive NLRP3 inflammasome activation can induce dysregulated inflammation leading to multiple organ failure and death during the acute phase of the disease. Moreover, this activation might become exhausted and contribute to post-septic immunosuppression, driving impaired functions of innate and adaptive immune cells. Targeting the NLRP3 inflammasome could thus be an attractive option in sepsis either through IL-1β and IL-18 antagonists or through inhibition of NLRP3 inflammasome pathway downstream components. Available treatments and results of first clinical trials will be discussed.

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.

NLRP3 inflammasome activation By 17β-estradiol is a potential therapeutic target in hepatocellular carcinoma treatment

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and it mostly arises as a consequence of persistent chronic inflammation. Recently, NLRP3 inflammasome has caught the attention of many research groups due to its involvement in different types of cancer. However, its direct role in HCC remains elusive. Our study aimed to evaluate the role of NLRP3 inflammasome and pyroptosis in HCC and to clarify the potential mechanism by which 17β-estradiol (E2) can be used as a protective factor against HCC. NLRP3, caspase-1 (CASP1) as well as gasdermin-D (GSDMD) mRNA expression levels were assessed in human HCC tissues and adjacent non-cancerous liver tissues. Also, HepG2 HCC cells were cultured and treated with E2, followed by detection of the mRNA levels of these three genes. Our results revealed that NLRP3, CASP1, and GSDMD mRNA expressions were significantly lower in HCC tissues than in controls, and this under-expression was closely correlated with advanced HCC stages and grades. In contrast, HepG2 HCC cells displayed significantly higher expression levels of NLRP3 inflammasome components and GSDMD in the two E2-treated groups compared to the untreated group. Also, NLRP3, CASP1, and GSDMD mRNA expression levels were positively correlated with each other. This study confirmed that lack of NLRP3 inflammasome is involved in HCC progression and 17β-estradiol-induced activation of NLRP3 inflammasome may be effective in HCC treatment as it inhibited tumor cell growth and proliferation by triggering CASP1-dependent pyroptosis in HCC cells.

Nanoparticles augment the therapeutic window of RT and immunotherapy for treating cancers: pivotal role of autophagy

Immunotherapies are now emerging as an efficient anticancer therapeutic strategy. Cancer immunotherapy utilizes the host's immune system to fight against cancer cells and has gained increasing interest due to its durable efficacy and low toxicity compared to traditional antitumor treatments, such as chemotherapy and radiotherapy (RT). Although the combination of RT and immunotherapy has drawn extensive attention in the clinical setting, the overall response rates are still low. Therefore, strategies for further improvement are urgently needed. Nanotechnology has been used in cancer immunotherapy and RT to target not only cancer cells but also the tumor microenvironment (TME), thereby helping to generate a long-term immune response. Nanomaterials can be an effective delivery system and a strong autophagy inducer, with the ability to elevate autophagy to very high levels. Interestingly, autophagy could play a critical role in optimal immune function, mediating cell-extrinsic homeostatic effects through the regulation of danger signaling in neoplastic cells under immunogenic chemotherapy and/or RT. In this review, we summarize the preclinical and clinical development of the combination of immunotherapy and RT in cancer therapy and highlight the latest progress in nanotechnology for augmenting the anticancer effects of immunotherapy and RT. The underlying mechanisms of nanomaterial-triggered autophagy in tumor cells and the TME are discussed in depth. Finally, we suggest the implications of these three strategies combined together to achieve the goal of maximizing the therapeutic advantages of cancer therapy and show recent advances in biomarkers for tumor response in the evaluation of those therapies.