Targeting tumor-infiltrating tregs for improved antitumor responses

Regulatory T Cells in Tumor Microenvironment: Therapeutic Approaches and Clinical Implications

Regulatory T cells (Tregs), previously referred to as suppressor T cells, represent a distinct subset of CD4+ T cells that are uniquely specialized for immune suppression. They are characterized by the constitutive expression of the transcription factor FoxP3 in their nuclei, along with CD25 (the IL-2 receptor α-chain) and CTLA-4 on their cell surface. Tregs not only restrict natural killer cell-mediated cytotoxicity but also inhibit the proliferation of CD4+ and CD8+ T-cells and suppress interferon-γ secretion by immune cells, ultimately impairing an effective antitumor immune response. Treg cells are widely recognized as a significant barrier to the effectiveness of tumor immunotherapy in clinical settings. Extensive research has consistently shown that Treg cells play a pivotal role in facilitating tumor initiation and progression. Conversely, the depletion of Treg cells has been linked to a marked delay in tumor growth and development.

Mediation Mendelian randomization analysis of immune cell phenotypes and glioma risk: unveiling the regulation of cerebrospinal fluid metabolites

BACKGROUND AND OBJECTIVE

Gliomas, particularly glioblastoma multiforme (GBM), are the most common primary central nervous system tumors in adults and are notoriously difficult to treat due to their high heterogeneity and invasiveness. Despite advances in molecular diagnostics and personalized therapies, prognosis remains poor. The immune system plays a critical role in glioma progression. This study employed mediation Mendelian randomization analysis to explore the relationships between immune cell phenotypes, cerebrospinal fluid metabolites, and glioma, aiming to uncover potential mechanisms of tumor progression and immune evasion.

METHOD

In this study, we employed several analytical methods including IVW, MR Egger, Simple mode, Weighted median, and Weighted mode, with IVW results being considered the primary basis. We assessed heterogeneity and pleiotropy, and used leave-one-out analysis to determine sensitivity, ensuring the stability and reliability of the results. The potential mediating effects of cerebrospinal fluid metabolites were investigated to explore the underlying mechanisms linking immune cell function and glioma. The GWAS data for immune cells, cerebrospinal fluid metabolites, and glioma used in this study were sourced from public databases.

RESULT

We identified nine risk immune cell phenotypes for glioma (such as CD19 on IgD( +) CD24(-)), and ten protective immune cell phenotypes (such as CD11c on monocytes). Mediation analysis revealed that levels of 7-alpha-hydroxy-3-oxo-4-cholestenoate (7-hoca) (MP = - 14.6%) and Palmitoyl dihydrosphingomyelin (d18:0/16:0) (MP = 7.9%) partially mediated the relationship between CD3 on CD39( +) resting Treg cells and glioma. Additionally, 7-hoca levels (MP = - 12.3%) and Phenyllactate (pla) levels (MP = 4.12%) partially mediated the association between FSC-A on NKT cells and glioma. Furthermore, Glycerophosphoinositol levels (MP = - 12.1%) and Orotate levels (MP = - 11.4%) partially mediated the relationship between Granulocyte adenylyl cyclase (Granulocyte AC) and glioma.

CONCLUSION

This study identified that specific immune cell phenotypes directly influence glioma risk and indirectly modulate this risk through cerebrospinal fluid metabolites. CD19 on IgD( +) CD24(-) B cells were identified as risk factors, while CD11c on monocytes were protective. Metabolites like 7-hoca and glycerophosphoinositol play key mediating roles. These findings enhance our understanding of glioma pathophysiology and suggest that immune modulation and metabolic intervention may be promising therapeutic strategies.

Applications of mRNA Delivery in Cancer Immunotherapy

Cancer treatment is continually advancing, with immunotherapy gaining prominence as a standard modality that has markedly improved the management of various malignancies. Despite these advancements, the efficacy of immunotherapy remains variable, with certain cancers exhibiting limited response and patient outcomes differing considerably. Thus, enhancing the effectiveness of immunotherapy is imperative. A promising avenue is mRNA delivery, employing carriers such as liposomes, peptide nanoparticles, inorganic nanoparticles, and exosomes to introduce mRNA cargos encoding tumor antigens, immune-stimulatory, or immune-modulatory molecules into the tumor immune microenvironment (TIME). This method aims to activate the immune system to target and eradicate tumor cells. In this review, we introduce the characteristics and limitations of these carriers and summarize the application and mechanisms of currently prevalent cargos in mRNA-based tumor treatment. Additionally, given the significant clinical application of immune checkpoint inhibitors (ICIs) and chimeric antigen receptor (CAR)-based cell therapies in solid tumors (including melanoma, non-small-cell lung cancer, head and neck squamous cell carcinoma, triple-negative breast cancer, gastric cancer) and leukemia, which have become first-line treatments, we highlight and discuss recent progress in combining mRNA delivery with ICIs, CAR-T, CAR-NK, and CAR-macrophage therapies. This combination enhances the targeting capabilities and efficacy of ICIs and CAR-cell-based therapies, while also mitigating the long-term off-target toxicities associated with conventional methods. Finally, we analyze the limitations of current mRNA delivery systems, such as nuclease-induced mRNA instability, immunogenicity risks, complex carrier production, and knowledge gaps concerning dosing and safety. Addressing these challenges is crucial for unlocking the potential of mRNA in cancer immunotherapy. Overall, exploring mRNA delivery enriches our comprehension of cancer immunotherapy and holds promise for developing personalized and effective treatment strategies, potentially enhancing the immune responses of cancer patients and extending their survival time.

Integrative Bioinformatics Analysis and Experimental Study of NLRP12 Reveal Its Prognostic Value and Potential Functions in Ovarian Cancer

NLRP12 plays a significant role in cellular functional behavior and immune homeostasis, influencing inflammation, tumorigenesis, and prognosis. This study aimed to explore its specific effects on the tumor microenvironment (TME) and its contribution to heterogeneity in ovarian cancer (OV) through bioinformatics analysis and experimental verification. Utilizing various bioinformatics databases and clinical specimens, we investigated NLRP12 expression and its relationship with OV prognosis and immune infiltration. In vitro assays were conducted to assess the impact of NLRP12 on the proliferation and invasion of OV cells. Our findings indicate that NLRP12 is upregulated in OV, with high expression correlating with a negative prognosis. Furthermore, NLRP12 expression demonstrated a positive correlation with the infiltration of various immune cells and the expression of immune checkpoint molecules in OV. Analysis of The Cancer Immunome Atlas (TCIA) database revealed that OV patients with lower NLRP12 expression may exhibit an enhanced response to immunotherapy, particularly CTLA4 blockers, a finding validated in animal experiments. Additionally, the study emphasized the role of NLRP12 in influencing the prognosis of OV patients by promoting epithelial-mesenchymal transition (EMT) in ovarian cancer cells. Finally, we identified a potential therapeutic compound, Schisandrin B (Schi B), which decreases NLRP12 expression in ovarian cancer cells by binding to the transcription factor SPI1 associated with NLRP12. Our findings suggest that NLRP12 serves as a crucial immune-related biomarker predicting poor outcomes in OV, and targeting NLRP12 may represent a promising therapeutic approach for OV patients in the future.

Promising Cellular Immunotherapy for Colorectal Cancer Using Classical Dendritic Cells and Natural Killer T Cells

Colorectal cancer (CRC) remains one of the leading causes of cancer-related morbidity and mortality around the world. Despite advances in surgery, chemotherapy, and targeted therapies, the prognosis for patients with metastatic or advanced CRC remains poor. Immunotherapies comprising immune checkpoint inhibitors showed disappointing responses in metastatic CRC (mCRC). However, cellular immunotherapy, specifically using classical dendritic cells (cDCs), may hold unique promise in immune recognition for CRC antigens. cDCs are substantial players in immune recognition and are instrumental in orchestrating innate and adaptive immune responses by processing and presenting tumor antigens to effector cells. Natural killer T (NKT) cells are insufficiently studied but unique effector cells because of their ability to bridge innate and adaptive immune reactions and the crosstalk with dendritic cells in cancer. This review explores the therapeutic potential of using both cDCs and NKT cells as a synergistic therapy in CRC, focusing on their biological roles, strategies for harnessing their capabilities, clinical applications, and the challenges within the tumor microenvironment. Both cDCs and NKT cells can be used as a new effective approach for cell-based therapies in cancers to provide a new hope for CRC patients that are challenging to treat.

Quantitative Approach to Explore Regulatory T Cell Activity in Immuno-Oncology

The failure of immunotherapies in cancer patients is being widely studied due to the complexities present in the tumor microenvironment (TME), where regulatory T cells (Treg) appear to actively participate in providing an immune escape mechanism for tumors. Therefore, therapies to specifically inhibit tumor-infiltrating Treg represent a challenge, because Treg are distributed throughout the body and provide physiological immune homeostasis to prevent autoimmune diseases. Characterization of immunological and functional profiles could help to identify the mechanisms that need to be inhibited or activated to ensure Treg modulation in the tumor. To address this, quantitative in silico approaches based on mechanistic mathematical models integrating multi-scale information from immune and tumor cells and the effect of different therapies have allowed the building of computational frameworks to simulate different hypotheses, some of which have subsequently been experimentally validated. Therefore, this review presents a list of diverse computational mathematical models that examine the role of Treg as a crucial immune resistance mechanism contributing to the failure of immunotherapy. In addition, this review highlights the relevance of certain molecules expressed in Treg that are associated with the TME immunosuppression, which could be incorporated into the mathematical model for a better understanding of the contribution of Treg modulation. Finally, different preclinical and clinical combinations of molecules are also included to show the trend of new therapies targeting Treg.

Regulatory T cells in immune checkpoint blockade antitumor therapy

Regulatory T cells (Tregs), an essential component of the human immune system, are a heterogeneous group of T lymphocytes with the ability to suppress immune responses and maintain immune homeostasis. Recent evidence indicates that Tregs may impair antitumor immunity and facilitate cancer progression by weakening functions of effector T cells (Teffs). Consequently, targeting Tregs to eliminate them from tumor microenvironments to improve Teffs' activity could emerge as an effective strategy for cancer immunotherapy. This review outlines the biology of Tregs, detailing their origins, classification, and crucial markers. Our focus lies on the complex role of Tregs in cancer's development, progression and treatment, particularly on their suppressive role upon antitumor responses via multiple mechanisms. We delve into Tregs' involvement in immune checkpoint blockade (ICB) therapy, their dual effect on cancer immunotherapy and their potential biomarkers for ICB therapy effectiveness. We also summarize advances in the therapies that adjust Tregs to optimize ICB therapy, which may be crucial for devising innovative cancer treatment strategies.

T cell receptor clonotype in tumor microenvironment contributes to intratumoral signaling network in patients with colorectal cancer

Single-cell RNA sequencing (scRNA-seq) has contributed to understanding cellular heterogeneity and immune profiling in cancer. The aim of the study was to investigate gene expression and immune profiling in colorectal cancer (CRC) using scRNA-seq. We analyzed single-cell gene expression and T cell receptor (TCR) sequences in 30 pairs of CRC and matched normal tissue. Intratumoral lymphocytes were measured with digital image analysis. CRC had more T cells, epithelial cells, and myeloid cells than normal colorectal tissue. CRCs with microsatellite instability had more abundant T cells than those without microsatellite instability. Immune cell compositions of CRC and normal colorectal tissue were inversely correlated. CD4 + or CD8 + proliferating T cells, CD4 + effector memory T cells, CD8 + naïve T cells, and regulatory T cells of CRC showed higher TCR clonal expansion. Tumor epithelial cells interacted with immune cells more strongly than normal. T cells, myeloid cells, and fibroblasts from CRCs of expanded T cell clonotypes showed increased expression of genes related to TNF and NFKB signaling and T cell activation. CRCs of expanded T cell clonotypes also showed stronger cellular interactions among immune cells, fibroblasts, and endothelial cells. Pro-inflammatory CXCL and TNF signaling were activated in CRCs of expanded T cell clonotype. In conclusion, scRNA-seq analysis revealed different immune cell compositions, differential gene expression, and diverse TCR clonotype dynamics in CRC. TCR clonality expansion is associated with immune activation through T cell signaling and chemokine signaling. Patients with CRCs of expanded clonotype can be promising candidates for immunotherapy.

Hypoxia-driven lncRNA CTD-2510F5.4: a potential player in hepatocellular carcinoma's prognostic stratification, cellular behavior, tumor microenvironment, and therapeutic response

BACKGROUND

Hepatocellular carcinoma (HCC) is a highly aggressive cancer with limited therapeutic options. Hypoxia is a common feature of the tumor microenvironment that reportedly promotes tumorigenesis. Long non-coding RNAs (lncRNAs) are a class of regulatory molecules with diverse functions in cancer biology. This study aimed to identify hypoxia-induced lncRNAs associated with HCC and evaluate their potential as prognostic and therapeutic biomarkers.

METHODS

We employed microarray and The Cancer Genome Atlas (TCGA) data to identify hypoxia-induced lncRNAs in HCC. Subsequently, we focused on CTD-2510F5.4, a candidate lncRNA, and predicted its functional roles in HCC using Gene Ontology (GO) and Guilt-by-Association (GBA) analyses. We validated its expression under hypoxia in Huh7 and HepG2 cells using RT-PCR. Functional assays, including CCK8, wound-healing, and transwell assays, were performed to assess the effects of CTD-2510F5.4 overexpression on HCC cell proliferation, invasion, and metastasis potential. Furthermore, we investigated the association between CTD-2510F5.4 expression and patient prognosis, tumor mutation signature, immune microenvironment characteristics, and therapeutic response to different treatment modalities.

RESULTS

Our data demonstrated a significant upregulation of CTD-2510F5.4 expression in response to hypoxia. Functional enrichment analyses revealed the involvement of CTD-2510F5.4 in cell cycle regulation, E2F targets, G2M checkpoint control, and MYC signaling pathways. Functionally, CTD-2510F5.4 overexpression promoted HCC cell proliferation, invasion, and metastasis. Patients with high CTD-2510F5.4 expression exhibited a worse prognosis, a higher prevalence of TP53 mutations, increased infiltration by immunosuppressive regulatory T cells, elevated expression of immune checkpoint molecules, and higher TIDE scores indicative of immune dysfunction and exclusion. Notably, patients with low CTD-2510F5.4 expression displayed greater sensitivity to immunotherapy and antiangiogenic therapy, while those with high expression responded better to chemotherapy.

CONCLUSION

Our findings suggest that CTD-2510F5.4 plays a critical role in HCC progression and immune modulation. Its potential as a prognostic biomarker and a predictor of therapeutic response warrants further investigation for personalized treatment strategies in HCC patients.

Spatial tumor immune microenvironment phenotypes in ovarian cancer

Immunotherapy has largely failed in ovarian carcinoma (OC), likely due to that the vast tumor heterogeneity and variation in immune response have hampered clinical trial outcomes. Tumor-immune microenvironment (TIME) profiling may aid in stratification of OC tumors for guiding treatment selection. Here, we used Digital Spatial Profiling combined with image analysis to characterize regions of spatially distinct TIME phenotypes in OC to assess whether immune infiltration pattern can predict presence of immuno-oncology targets. Tumors with diffuse immune infiltration and increased tumor-immune spatial interactions had higher presence of IDO1, PD-L1, PD-1 and Tim-3, while focal immune niches had more CD163 macrophages and a preliminary worse outcome. Immune exclusion was associated with presence of Tregs and Fibronectin. High-grade serous OC showed an overall stronger immune response and presence of multiple targetable checkpoints. Low-grade serous OC was associated with diffuse infiltration and a high expression of STING, while endometrioid OC had higher presence of CTLA-4. Mucinous and clear cell OC were dominated by focal immune clusters and immune-excluded regions, with mucinous tumors displaying T-cell rich immune niches.

The Neuroimmune Axis and Its Therapeutic Potential for Primary Liver Cancer

The autonomic nervous system plays an integral role in motion and sensation as well as the physiologic function of visceral organs. The nervous system additionally plays a key role in primary liver diseases. Until recently, however, the impact of nerves on cancer development, progression, and metastasis has been unappreciated. This review highlights recent advances in understanding neuroanatomical networks within solid organs and their mechanistic influence on organ function, specifically in the liver and liver cancer. We discuss the interaction between the autonomic nervous system, including sympathetic and parasympathetic nerves, and the liver. We also examine how sympathetic innervation affects metabolic functions and diseases like nonalcoholic fatty liver disease (NAFLD). We also delve into the neurobiology of the liver, the interplay between cancer and nerves, and the neural regulation of the immune response. We emphasize the influence of the neuroimmune axis in cancer progression and the potential of targeted interventions like neurolysis to improve cancer treatment outcomes, especially for hepatocellular carcinoma (HCC).

Characterization of a G2M checkpoint-related gene model and subtypes associated with immunotherapy response for clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) presents challenges in early diagnosis and effective treatment. In this study, we aimed to establish a prognostic model based on G2M checkpoint-related genes and identify associated clusters in ccRCC through clinical bioinformatic analysis and experimental validation. Utilizing a single-cell RNA dataset (GSE159115) and bulk-sequencing data from The Cancer Genome Atlas (TCGA) database, we analyzed the G2M checkpoint pathway in ccRCC. Differential expression analysis identified 45 genes associated with the G2M checkpoint, leading to the construction of a predictive model with four key genes (E2F2, GTSE1, RAD54L, and UBE2C). The model demonstrated reliable predictive ability for 1-, 3-, and 5-year overall survival, with AUC values of 0.794, 0.790, and 0.794, respectively. Patients in the high-risk group exhibited a worse prognosis, accompanied by significant differences in immune cell infiltration, immune function, TIDE and IPS scores, and drug sensitivities. Two clusters of ccRCC were identified using the "ConsensusClusterPlus" package, cluster 1 exhibited a worse survival rate and was resistant to chemotherapeutic drugs of Axitinib, Erlotinib, Pazopanib, Sunitinib, and Temsirolimus, but not Sorafenib. Targeted experiments on RAD54L, a gene involved in DNA repair processes, revealed its crucial role in inhibiting proliferation, invasion, and migration in 786-O cells. In conclusion, our study offers valuable insights into the molecular mechanisms underlying ccRCC, identifying potential prognostic genes and molecular subtypes associated with the G2M checkpoint. These findings hold promise for guiding personalized treatment strategies in the management of ccRCC.

Tumor Microenvironment: Cellular Interaction and Metabolic Adaptations

The tumor microenvironment (TME) plays a critical role in cancerogenesis [...].