Mechanotransduction in response to ECM stiffening impairs cGAS immune signaling in tumor cells

Reconstructing the hepatocellular carcinoma microenvironment: the current status and challenges of 3D culture technology

Hepatocellular carcinoma (HCC), with high incidence and mortality rates among digestive system diseases, has become a focal point for researchers. However, the more we learn about HCC, the more apparent it becomes that our understanding is still superficial. The successes and failures of numerous studies underscore the urgent need for precision medicine in cancer treatment. A crucial aspect of preclinical research in precision medicine is the experimental model, particularly cell culture models. Among these, 3D cell culture models can effectively integrate and simulate the tumor microenvironment, closely reflecting the in vivo conditions of patients. This capability provides a solid theoretical foundation for personalized treatment approaches. In this review, we first outline the common in vitro 3D cell culture models and examine the essential elements within the tumor microenvironment, followed by insights into the current state and future developments of 3D in vitro cell models for HCC.

Identification of the specific characteristics of neuroendocrine prostate cancer: Immune status, hub genes and treatment

Castration-resistant prostate cancer (CRPC) marks the advanced phase of prostate malignancy, manifested through two principal subtypes: castration-resistant adenocarcinoma (CRPC-adeno) and neuroendocrine prostate cancer (NEPC). This study aims to identify unique central regulatory genes, assess the immunological landscape, and explore potential therapeutic strategies specifically tailored to NEPC. We discovered 1444 differentially expressed genes (DEGs) distinguishing between the two cancer types and identified 12 critical hub genes. Notably, CHST1, MPPED2, and RIPPLY3 emerged as closely associated with the immune cell infiltration pattern, establishing them as top candidates. Prognostic analysis highlighted the potential critical roles of CHST1 and MPPED2 in prostate cancer development, findings corroborated through in vitro and in vivo assays. Moreover, we validated the functions and expression levels of CHST1, MPPED2, and RIPPLY3 in NEPC using cell lines, animal models and human tissues. In the final step, we found that imatinib might be the drug specific to NEPC, which was further confirmed by in vitro cell assay. Our results revealed the clinical characteristics, molecular features, immune cell infiltration pattern in CRPC-adeno and NEPC, and identified and confirmed CHST1, MPPED2, and RIPPLY3 as the critical genes in the development in prostate cancer and NEPC. We also predicted and validated imatinib as the potential specific drugs to NEPC.

The fibroinflammatory response in cancer

Fibroinflammation refers to the highly integrated fibrogenic and inflammatory responses mediated by the concerted function of fibroblasts and innate immune cells in response to tissue perturbation. This process underlies the desmoplastic remodelling of the tumour microenvironment and thus plays an important role in tumour initiation, growth and metastasis. More specifically, fibroinflammation alters the biochemical and biomechanical signalling in malignant cells to promote their proliferation and survival and further supports an immunosuppressive microenvironment by polarizing the immune status of tumours. Additionally, the presence of fibroinflammation is often associated with therapeutic resistance. As such, there is increasing interest in targeting this process to normalize the tumour microenvironment and thus enhance the treatment of solid tumours. Herein, we review advances made in unravelling the complexity of cancer-associated fibroinflammation that can inform the rational design of therapies targeting this.

Mechanosensitive ion channel-related genes in hepatocellular carcinoma: Unraveling prognostic genes and their roles in drug resistance and immune modulation

Background and aims

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide, and its etiology involves a complex interplay of genetic and environmental factors. Despite advancements in our understanding of HCC biology and the development of novel therapeutic strategies, the molecular mechanisms underlying its onset, progression, and resistance to therapy remain largely vague. This study aimed to investigate the role of mechanosensitive ion channel-related genes (MICRGs) in HCC, focusing on their potential as prognostic biomarkers and their involvement in immune modulation and drug resistance.

Methods

A comprehensive analysis was conducted using The Cancer Genome Atlas database to identify MICRGs that are upregulated in HCC. Gene expression profiling, bioinformatics tools, and functional experiments were employed to elucidate the role of these channels. In addition, protein-protein interaction (PPI) network analyses and enrichment analyses were performed to explore the biological significance of these genes. An immune cell infiltration analysis was also conducted to understand MICRG-related immune landscape. Single-cell RNA sequencing (scRNA-seq) data were utilized to identify MICRGs in different cell types within the HCC tissue. Deep-learning neural network analysis across patient cohorts was conducted to identify genes associated with sorafenib resistance. Knockdown experiments, cell viability assays, and apoptosis assays on HCC cell lines were performed to examine the role of Piezo-type mechanosensitive ion channel component 1 (PIEZO1) in sorafenib resistance.

Results

The analysis identified a subset of MICRGs, including PIEZO1, that were significantly upregulated in HCC and associated with poor prognosis. The PPI network analysis revealed complex interactions among these genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses proposed the involvement of these genes in calcium signaling pathways. Immune cell infiltration analysis demonstrated distinct associations between MICRGs and various immune subpopulations, highlighting their potential roles in immune modulation. scRNA-seq data indicated the upregulation of MICRGs in various cell types in HCC tissues, particularly in endothelial cells and tumor-associated macrophages. Deep-learning neural network analysis across different patient cohorts identified PIEZO1 as a crucial regulator of sorafenib resistance in HCC, which was further validated by functional assays on HCC cell lines.

Conclusions

This study provides evidence that MICRGs, particularly PIEZO1, take on crucial roles in HCC progression and drug resistance. The upregulation of PIEZO1 in HCC cells is associated with poor prognosis and resistance to sorafenib. These findings indicate that PIEZO1 could serve as a potential therapeutic target for overcoming drug resistance and a prognostic biomarker in HCC. Future studies should focus on validating these findings in larger patient cohorts and exploring the functional implications of targeting PIEZO1 in preclinical models.

Comprehensive analysis of the multifaceted role of ITGAV in digestive system cancer progression and immune infiltration

Background

Digestive system cancers are among the most common malignancies, exhibiting consistently high incidence and mortality rates, yet effective detection and treatment targets remain limited. Integrin αv (ITGAV, CD51) is a significant member of the integrin family, widely recognized for its role in mediating interactions between cells and the extracellular matrix, as well as intracellular signaling. In recent years, ITGAV has been found to have significantly elevated expression in multiple tumors, such as prostate cancer, breast cancer, and osteosarcoma, and was considered to be a key component in various stages of tumor progression. However, no systematic digestive system cancer analysis has been conducted to explore its function in prognosis, diagnosis, and immunology.

Methods

Transcriptome sequencing and clinical data of samples were obtained from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression Project (GTEx), Human Protein Atlas (HPA), cBioPortal, TIMER and TISIDB databases. Bioinformatics methods were employed to investigate the potential oncogenicity of ITGAV, focusing specifically on the analysis of its prognosis, diagnostic value, and immune infiltration level of ITGAV in digestive system cancers. In addition, GO, KEGG, and PPI network analysis revealed the biological functions and related signaling pathways related to ITGAV. Finally, the role of ITGAV in regulating cancer progression was experimentally verified using hepatocellular carcinoma and pancreatic cancer as examples.

Results

We found that ITGAV was highly expressed in multiple digestive system cancers. In addition, high expression of ITGAV was closely associated with poor prognosis and showed potential for early diagnosis. Enrichment of pathways related to extracellular matrix organizing processes and tumor migratory movements was identified. In vitro, results showed that the knockdown of ITGAV significantly inhibited the migratory movement ability of hepatocellular carcinoma and pancreatic cancer cells, while its overexpression significantly promoted the migration of the above cells. Finally, immunoassays showed a significant correlation between ITGAV expression and the infiltration level of various immune cells, further clarifying the critical role of ITGAV in the tumor immune microenvironment.

Conclusion

Our results elucidated the importance of ITGAV in the prognostic assessment, early diagnosis, and targeted immunotherapy of digestive system cancers, and revealed its multifaceted role in regulating cancer progression.

Advances in understanding ferroptosis mechanisms and their impact on immune cell regulation and tumour immunotherapy

Ferroptosis is a novel mode of iron-dependent non-apoptotic cell death that occurs mainly due to excessive accumulation of lipid peroxides. Numerous studies in recent years have shown that ferroptosis plays a vital role in the organism and has important interactions with immune cells. Ferroptosis has been shown to have great potential in tumour therapy through studying its mechanism of action. In addition, ferroptosis plays a major role in many types of tumour cells that can potently suppress the tumourigenesis and metastasis, provide a basis for the treatment of many malignant tumour diseases and become a novel therapeutic modality of antitumour immunity in the clinic. Current tumour immunotherapy for ferroptosis in combination with other conventional oncological modalities is not well elaborated. In this paper, we mainly discuss the connection of ferroptosis with immune cells and their mediated tumour immunotherapy in order to provide a better theoretical basis and new thinking about ferroptosis mediated antitumour immunity.

The key role of matrix stiffness in colorectal cancer immunotherapy: mechanisms and therapeutic strategies

Increased matrix stiffness within the colorectal cancer (CRC) tumor microenvironment (TME) has emerged as a pivotal determinant of immunotherapy outcomes. This review discusses the role of aberrant extracellular matrix (ECM) deposition and cross-linking in augmenting matrix stiffness, a phenomenon that not only scaffolds the tumor architecture but also contributes to tumorigenicity and immunologic evasion. Herein, we critically appraise the influence of matrix stiffness on the immunotherapeutic landscape of CRC, focusing on its capacity to impede therapeutic efficacy by modulating immune cell infiltration, activation, and functional performance. The review explores the molecular dynamics whereby matrix stiffness prompts tumor evolution, highlighting the integral role of integrin signaling, cancer-associated fibroblasts (CAFs), and the process of epithelial-mesenchymal transition (EMT). We bring to the fore the paradoxical impact of an indurated ECM on immune effector cells, chiefly T cells and macrophages, which are indispensable for immune surveillance and the execution of immunotherapeutic strategies, yet are markedly restrained by a fibrotic matrix. Furthermore, we examine how matrix stiffness modulates immune checkpoint molecule expression, thereby exacerbating the immunosuppressive milieu within the TME and attenuating immunotherapeutic potency. Emergent therapeutic regimens targeting matrix stiffness-including matrix modulators, inhibitors of mechanotransduction signaling pathways, and advanced biomaterials that mimic the ECM-proffer novel modalities to potentiate immunotherapy responsiveness. By refining the ECM's biomechanical attributes, the mechanical barriers posed by the tumor stroma can be improved, facilitating robust immune cell penetration and activity, and thereby bolstering the tumor's susceptibility to immunotherapy. Ongoing clinical trials are evaluating these innovative treatments, particularly in combination with immunotherapies, with the aim of enhancing clinical outcomes for CRC patients afflicted by pronounced matrix stiffness.

Pseudorabies virus usurps non-muscle myosin heavy chain IIA to dampen viral DNA recognition by cGAS for antagonism of host antiviral innate immunity

Alphaherpesvirus pseudorabies virus (PRV) causes severe economic losses to the global pig industry and has garnered increasing attention due to its broad host range including humans. PRV has developed a variety of strategies to antagonize host antiviral innate immunity. However, the underlying mechanisms have not been fully elucidated. In our previous work, we demonstrated that non-muscle myosin heavy chain IIA (NMHC-IIA), a multifunctional cytoskeleton protein, attenuates innate immune responses triggered by RNA viruses. In the current study, we reported a previously unrecognized role of NMHC-IIA in counteracting PRV-induced cyclic GMP-AMP synthase (cGAS)-dependent type I interferon (IFN-I) production. Mechanistically, PRV infection led to an elevation of NMHC-IIA, strengthening the interaction between poly (ADP-ribose) polymerase 1 (PARP1) and cGAS. This interaction impeded cGAS recognition of PRV DNA and hindered downstream signaling activation. Conversely, inhibition of NMHC-IIA by Blebbistatin triggered innate immune responses and enhanced resistance to PRV proliferation both in vitro and in vivo. Taken together, our findings unveil that PRV utilizes NMHC-IIA to antagonize host antiviral immune responses via impairing DNA sensing by cGAS. This in-depth understanding of PRV immunosuppression not only provides insights for potential PRV treatment strategies but also highlights NMHC-IIA as a versatile immunosuppressive regulator usurped by both DNA and RNA viruses. Consequently, NMHC-IIA holds promise as a target for the development of broad-spectrum antiviral drugs.IMPORTANCECyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) axis plays a vital role in counteracting alphaherpesvirus infections. Alphaherpesviruses exploit various strategies for antagonizing cGAS-STING-mediated antiviral immune responses. However, limited examples of pseudorabies virus (PRV)-caused immunosuppression have been documented. Our findings reveal a novel role of non-muscle myosin heavy chain IIA (NMHC-IIA) in suppressing PRV-triggered innate immune responses to facilitate viral propagation both in vitro and in vivo. In detail, NMHC-IIA recruits poly (ADP-ribose) polymerase 1 (PARP1) to augment its interaction with cGAS, which impairs cGAS recognition of PRV DNA. Building on our previous demonstration of NMHC-IIA's immunosuppressive role during RNA virus infections, these findings indicate that NMHC-IIA acts as a broad-spectrum suppressor of host antiviral innate immunity in response to both DNA and RNA viruses. Therefore, NMHC-IIA will be a promising target for the development of comprehensive antiviral strategies.

Harnessing the cGAS-STING pathway to potentiate radiation therapy: current approaches and future directions

In this review, we cover the current understanding of how radiation therapy, which uses ionizing radiation to kill cancer cells, mediates an anti-tumor immune response through the cGAS-STING pathway, and how STING agonists might potentiate this. We examine how cGAS-STING signaling mediates the release of inflammatory cytokines in response to nuclear and mitochondrial DNA entering the cytoplasm. The significance of this in the context of cancer is explored, such as in response to cell-damaging therapies and genomic instability. The contribution of the immune and non-immune cells in the tumor microenvironment is considered. This review also discusses the burgeoning understanding of STING signaling that is independent of inflammatory cytokine release and the various mechanisms by which cancer cells can evade STING signaling. We review the available data on how ionizing radiation stimulates cGAS-STING signaling as well as how STING agonists may potentiate the anti-tumor immune response induced by ionizing radiation. There is also discussion of how novel radiation modalities may affect cGAS-STING signaling. We conclude with a discussion of ongoing and planned clinical trials combining radiation therapy with STING agonists, and provide insights to consider when planning future clinical trials combining these treatments.