Activation of NOD1 on tumor-associated macrophages augments CD8+ T cell-mediated antitumor immunity in hepatocellular carcinoma

Lactobacilli-Mediated Regulation of the Microbial-Immune Axis: A Review of Key Mechanisms, Influencing Factors, and Application Prospects

Lactobacilli, as the main member of food microorganisms, is an important component of the intestinal microbial community and plays crucial roles in regulating the immune capacity of the body. This review provides a comprehensive exploration of the key components of Lactobacilli-mediated immune regulation effects, including the immunogenic components (peptidoglycan and lipoteichoic acid) and metabolites (short-chain fatty acids, bacteriocins, and exopolysaccharides), which can interact with host immune cell receptors to initiate complex immune signaling pathways. In addition, the immunomodulatory activity can be influenced by multiple factors including species differences, host-related factors (age, physiological conditions, and gut microbiota), and environmental factors (nutrient substrates, temperatures, etc.), and the application strategies including precision probiotic development, gene-editing driven engineering, and nanocarrier systems have also been proposed to enhance the immunomodulatory potential. Finally, this review provides the theoretical basis for microbial intervention in immune-related diseases and offers prospects for applications in the food and pharmaceutical industries.

Exploring the Role of Cellular Interactions in the Colorectal Cancer Microenvironment

Colorectal cancer (CRC) stands as one of the tumors with globally high incidence and mortality rates. In recent years, researchers have extensively explored the role of the tumor immune microenvironment (TME) in CRC, highlighting the crucial influence of immune cell populations in driving tumor progression and shaping therapeutic outcomes. The TME encompasses an array of cellular and noncellular constituents, spanning tumor cells, immune cells, myeloid cells, and tumor-associated fibroblasts, among others. However, the cellular composition within the TME is highly dynamic, evolving throughout different stages of tumor progression. These shifts in cell subpopulation proportions lead to a gradual transition in the immune response, shifting from an early antitumor growth to a late-stage environment that supports tumor survival. Therefore, it is crucial to further investigate and understand the complex interactions among the various cell populations within the TME. In this review, we explore the key cellular components of varying origins, subpopulations with shared origins, and noncellular elements within the CRC TME, examining their interconnections and critical considerations for developing personalized and precise immunotherapy strategies.

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.

High expression of nucleotide-binding oligomerization domain protein 1 correlates with poor prognosis and immune cell infiltration in Glioblastoma Multiforme patients

Nucleotide-binding oligomerization domain protein 1 (NOD1) is one of the innate immune receptors that has been associated with tumorigenesis and abnormally expressed in various cancers. However, the role of NOD1 in Glioblastoma Multiforme (GBM) has not been investigated. We used the Tumor Immune Estimate Resource (TIMER) database to compare the differential expression of NOD1 in various tumors. NOD1 expression in GBM was further validated in the GEO database, and the survival of NOD1 was assessed by the Kaplan-Meier method. Clinical samples were collected to validate NOD1 expression. GSEA was carried out to expound on NOD1-related pathways involved in GBM. NOD1 co-expression and enrichment analysis were performed using the Linked Omics database and R software. The relationship between immune infiltrates and NOD1 expression was assessed by TIMER. Besides, the correlation between NOD1 and immune signatures (immunomodulators and chemokine) was evaluated by TISIDB. We found that NOD1 expression was significantly upregulated in GBM patients, and higher expression of NOD1 was associated with a poor prognosis. GSEA and enrichment analysis revealed that NOD1 might play a vital role in immune response and GBM progression. TIMER analysis showed a positive correlation between NOD1 expression and 17 types of tumor-infiltrating immune cells. Moreover, NOD1 expression was positively correlated with the expression of chemokine and immunomodulators in GBM. Overall, our findings suggest that NOD1 is a promising prognostic biomarker and is associated with immune cell infiltration in GBM, making it a potential diagnostic biomarker for this aggressive brain cancer.

Unveiling the role of Pleckstrin-2 in tumor progression and immune modulation: insights from a comprehensive pan-cancer analysis with focus on lung cancer

Cancer remains a leading cause of mortality globally, highlighting the need for novel biomarkers to enhance prognosis and therapeutic strategies. Pleckstrin-2 (PLEK2), a member of the pleckstrin family, has been implicated in processes critical to tumor progression, but its role across cancers remains underexplored. This study systematically examined the expression patterns, prognostic relevance, and functional impact of PLEK2 across multiple cancer types. Using data from The Cancer Genome Atlas (TCGA), Genotype Tissue Expression Project (GTEx), and the Human Protein Atlas, we analyzed PLEK2 expression in both cancerous and normal tissues, revealing significant overexpression of PLEK2 in various cancers at the mRNA and protein levels. Single-cell RNA sequencing further indicated predominant expression of PLEK2 in tumor cells and macrophages within the tumor microenvironment. Survival analysis demonstrated that elevated PLEK2 expression correlated with poor prognosis in specific cancers, though its impact varied across cancer types. Functional assays showed that PLEK2 knockdown inhibited proliferation and migration in human cancer cell lines. In vivo studies using a Lewis lung carcinoma (LLC) model confirmed that PLEK2 knockdown suppressed tumor growth and enhanced the efficacy of PD-1 immunotherapy. Mechanistically, PLEK2 knockdown was associated with reduced AKT pathway activation, diminished tumor-associated macrophage infiltration, and increased CD8 T cell presence. Compounds like Navitoclax were also identified as potential PLEK2 inhibitors. In conclusion, PLEK2 played a multifaceted role in cancer progression and immune response modulation. Targeting PLEK2 might suppress tumor growth and overcome immunotherapy resistance, offering a promising biomarker and therapeutic target to improve cancer treatment outcomes.