Dendritic cells in the tumor microenvironment: prognostic and theranostic impact

The role of RNA methylation in tumor immunity and its potential in immunotherapy

RNA methylation, a prevalent post-transcriptional modification, has garnered considerable attention in research circles. It exerts regulatory control over diverse biological functions by modulating RNA splicing, translation, transport, and stability. Notably, studies have illuminated the substantial impact of RNA methylation on tumor immunity. The primary types of RNA methylation encompass N6-methyladenosine (m6A), 5-methylcytosine (m5C), N1-methyladenosine (m1A), and N7-methylguanosine (m7G), and 3-methylcytidine (m3C). Compelling evidence underscores the involvement of RNA methylation in regulating the tumor microenvironment (TME). By affecting RNA translation and stability through the "writers", "erasers" and "readers", RNA methylation exerts influence over the dysregulation of immune cells and immune factors. Consequently, RNA methylation plays a pivotal role in modulating tumor immunity and mediating various biological behaviors, encompassing proliferation, invasion, metastasis, etc. In this review, we discussed the mechanisms and functions of several RNA methylations, providing a comprehensive overview of their biological roles and underlying mechanisms within the tumor microenvironment and among immunocytes. By exploring how these RNA modifications mediate tumor immune evasion, we also examine their potential applications in immunotherapy. This review aims to provide novel insights and strategies for identifying novel targets in RNA methylation and advancing cancer immunotherapy efficacy.

Calpain 8 as a potential biomarker regulates the progression of pancreatic cancer via EMT and AKT/ERK pathway

Calpain is a non-lysozyme, calcium-dependent intracellular cysteine protease that has been shown to play a role in tumor proliferation, survival, migration, invasion, and apoptosis. Dysregulation of calpain expression is closely related to tumorigenesis. However, the role of calpain-8 (CAPN8), as a member of the calpain family, in pancreatic cancer (PC) is remains unclear. In elucidating the mechanism of CAPN8 in PC, a comprehensive bioinformatics analysis and in vitro experiments were conducted. The TCGA database was used to explore the expression level of CAPN8, and the results in PC tissues and cell lines were verified. Then, the correlation between CAPN8 and clinicopathological features was analyzed. Additionaly, promoter methylation, immune infiltration, and GO/KEGG enrichment analyses were performed. Lastly, the molecular mechanism of CAPN8 in PC was investigated by using cell counting kit (CCK) 8, transwell, wound healing, Western blot assays, and so on. Results indicate that CAPN8 was highly expressed in PC and correlated with poor prognosis and advanced TNM stage. In addition, a low level of immune infiltration was closely associated with the high expression level of CAPN8. Based on these findings, we hypothesized that CAPN8 is a potential biomarker that regulates progression of PC via EMT and the AKT/ERK pathway. SIGNIFICANCE: Through comprehensive biological information and in vitro experiments, CAPN8 has been confirmed to play an important role in regulating pancreatic cancer (PC) proliferation, migration and invasion. CAPN8 is found to be closely related to the diagnosis, survival and prognosis of PC. Above all, CAPN8 may be a potential biomarker for the diagnosis and prognosis of PC.

Biomimetic Nano-Regulator that Induces Cuproptosis and Lactate-Depletion Mediated ROS Storm for Metalloimmunotherapy of Clear Cell Renal Cell Carcinoma

Herein, a ccRCC targeting nanodrug is designed to enhance chemodynamic therapy (CDT) as well as activate cuproptosis and tumor immunotherapy via ccRCC cell membrane modifying CuO@Gd2O3 yolk-like particles (CGYL) loaded with lactate oxidase (LOx) (mCGYL-LOx). Benefiting from the homologous targeting effect of Renca cell membranes, the mCGYS-LOx can be effectively internalized by Renca cells, open the "gate", and then release LOx and copper (Cu) ions. LOx can catalyze excessive lactate in Renca cells into H2O2, following that the produced H2O2 is further converted by Cu ions to the highly toxic ·OH, contributing to tumor CDT. Meanwhile, the excessive Cu ions effectively trigger tumor cuproptosis. These synergistic effects induce the release of damage associated molecular patterns (DAMPs) and activate immunogenic cell death (ICD), leading to DC maturation and infiltration of immune effector cells. Moreover, LOx-mediated lactate consumption downregulates the expression of PD-L1, crippling tumor immune escape. In addition, the mCGYL-LOx improves T1-weighted MRI signal, allowing for accurate diagnosis of ccRCC. This study demonstrates that the mCGYL-LOx has great potential for improving therapy of ccRCC via the synergistic actions of CDT and cuproptosis as well as immunotherapy.

Boosting Checkpoint Immunotherapy with Biomimetic Nanodrug Delivery Systems

Immune checkpoint blockade (ICB) has achieved unprecedented progress in tumor immunotherapy by blocking specific immune checkpoint molecules. However, the high biodistribution of the drug prevents it from specifically targeting tumor tissues, leading to immune-related adverse events. Biomimetic nanodrug delivery systems (BNDSs) readily applicable to ICB therapy have been widely developed at the preclinical stage to avoid immune-related adverse events. By exploiting or mimicking complex biological structures, the constructed BNDS as a novel drug delivery system has good biocompatibility and certain tumor-targeting properties. Herein, the latest findings regarding the aforementioned therapies associated with ICB therapy are highlighted. Simultaneously, prospective bioinspired engineering strategies can be designed to overcome the four-level barriers to drug entry into lesion sites. In future clinical translation, BNDS-based ICB combination therapy represents a promising avenue for cancer treatment.

Metabolomics reveals ascorbic acid inhibits ferroptosis in hepatocytes and boosts the effectiveness of anti-PD1 immunotherapy in hepatocellular carcinoma

BACKGROUND

Immunotherapy combined with molecular targeted therapy is increasingly popular in patients with advanced hepatocellular carcinoma (HCC). However, immune-related adverse events(irAEs) brought on by immunotherapy increase the likelihood of side effects, thus it is important to look into ways to address this issue.

METHODS

Different metabolite patterns were established by analyzing metabolomics data in liver tissue samples from 10 patients(divided into severe and mild liver injury) before and after immuno-targeted therapy. After establishing a subcutaneous tumor model of HCC, the mice were divided into PBS group, ascorbic acid(AA) group, and anti-PD1 + tyrosine kinase inhibitor (TKI) group, anti-PD1 + TKI + AA group. Liver tissue were stained with hematoxylin-eosin staining(HE) and the content of aspartate transaminase (AST) and alanine transaminase(ALT) in blood were determined. The mechanism was confirmed by western blotting, mass cytometry, and other techniques.

RESULTS

Through metabolomics analysis, AA was significantly reduced in the sample of patients with severe liver injury caused by immuno-targeted therapy compared to patients with mild liver injury. The addition of AA in vivo experiments demonstrated a reduction in liver injury in mice. In the liver tissues of the anti-PD1 + TKI + AA group, the protein expressions of SLC7A11,GPX4 and the level of glutathione(GSH) were found to be higher compared to the anti-PD1 + TKI group. Mass cytometry analysis revealed a significant increase in the CD11b+CD44+ PD-L1+ cell population in the AA group when compared to the PBS group.

CONCLUSIONS

AA could reduce liver injury by preventing hepatocyte SLC7A11/GPX4 ferroptosis and improve the immunotherapy effect of anti-PD1 by boosting CD11b+CD44+PD-L1+cell population in HCC.

LncRNAs in Immune and Stromal Cells Remodel Phenotype of Cancer Cell and Tumor Microenvironment

Emerging studies suggest that long non-coding RNAs (lncRNAs) participate in the mutual regulation of cells in tumor microenvironment, thereby affecting the anti-tumor immune activity of immune cells. Additionally, the intracellular pathways mediated by lncRNAs can affect the expression of immune checkpoints or change the cell functions, including cytokines secretion, of immune and stromal cells in tumor microenvironment, which further influences cancer patients' prognosis and treatment response. With the in-depth research, lncRNAs have shown great potency as a new immunotherapy target and predict immunotherapy response. The research on lncRNAs provides us with a new insight into developing new immunotherapy drugs and predicting the outcome of immunotherapy. With development of RNA sequencing technology, amounts of lncRNAs were found to be dysregulated in immune and stromal cells rather than tumor cells. These lncRNAs function through ceRNA network or regulating transcript factor activity, thus leading abnormal differentiation and activation of immune and stromal cells. Here, we review the function of lncRNAs in the immune microenvironment and focus on the alteration of lncRNAs in immune and stromal cells, and discuss how these alterations affect tumor growth, metastasis and treatment response.

Dual-Responsive Nanomedicine Activates Programmed Antitumor Immunity through Targeting Lymphatic System

Effective antitumor immunotherapy depends on evoking a cascade of cancer-immune cycles with lymph nodes (LNs) as the initial sites for activating antitumor immunity, making drug administration through the lymphatic system highly attractive. Here, we describe a nanomedicine with dual responsiveness to pH and enzyme for a programmed activation of antitumor immune through the lymphatic system. The proposed nanomedicine can release the STING agonist diABZI-C2-NH2 in the LNs' acidic environment to activate dendritic cells (DCs) and T cells. Then, the remaining nanomedicine hitchhikes on the activated T cells (PD-1+ T cells) through binding to PD-1, resulting in an effective delivery into tumor tissues owing to the tumor-homing capacity of PD-1+ T cells. The enzyme matrix metalloproteinase-2 (MMP-2) being enriched in tumor tissue triggers the release of PD-1 antibody (aPD-1) which exerts immune checkpoint blockade (ICB) therapy. Eventually, the nanomedicine delivers a DNA methylation inhibitor GSK-3484862 (GSK) into tumor cells, and then the latter combines with granzyme B (GZMB) to trigger tumor cell pyroptosis. Consequently, the pyroptotic tumor cells induce robust immunogenic cell death (ICD) enhancing the DCs maturation and initiating the cascading antitumor immune response. Study on a 4T1 breast tumor mouse model demonstrates the prominent antitumor therapeutic outcome of this nanomedicine through creating a positive feedback loop of cancer-immunity cycles including immune activation in LNs, T cell-mediated drug delivery, ICB therapy, and tumor cell pyroptosis-featured ICD.

Nanodrug Delivery Systems in Antitumor Immunotherapy

Cancer has become one of the most important factors threatening human health, and the global cancer burden has been increasing rapidly. Immunotherapy has become another clinical research hotspot after surgery, chemotherapy, and radiotherapy because of its high efficiency and tumor metastasis prevention. However, problems such as lower immune response rate and immune-related adverse reaction in the clinical application of immunotherapy need to be urgently solved. With the development of nanodrug delivery systems, various nanocarrier materials have been used in the research of antitumor immunotherapy with encouraging therapeutic results. In this review, we mainly summarized the combination of nanodrug delivery systems and immunotherapy from the following 4 aspects: (a) nanodrug delivery systems combined with cytokine therapy to improve cytokines delivery in vivo; (b) nanodrug delivery systems provided a suitable platform for the combination of immune checkpoint blockade therapy with other tumor treatments; (c) nanodrug delivery systems helped deliver antigens and adjuvants for tumor vaccines to enhance immune effects; and (d) nanodrug delivery systems improved tumor treatment efficiency and reduced toxicity for adoptive cell therapy. Nanomaterials chosen by researchers to construct nanodrug delivery systems and their function were also introduced in detail. Finally, we discussed the current challenges and future prospects in combining nanodrug delivery systems with immunotherapy.

Modulator of TMB-associated immune infiltration (MOTIF) predicts immunotherapy response and guides combination therapy

Patients with high tumor mutational burden (TMB) levels do not consistently respond to immune checkpoint inhibitors (ICIs), possibly because a high TMB level does not necessarily result in adequate infiltration of CD8+ T cells. Using bulk ribonucleic acid sequencing (RNA-seq) data from 9311 tumor samples across 30 cancer types, we developed a novel tool called the modulator of TMB-associated immune infiltration (MOTIF), which comprises genes that can determine the extent of CD8+ T cell infiltration prompted by a certain TMB level. We confirmed that MOTIF can accurately reflect the integrity and defects of the cancer-immunity cycle. By analyzing 84 human single-cell RNA-seq datasets from 32 types of solid tumors, we revealed that MOTIF can provide insights into the diverse roles of various cell types in the modulation of CD8+ T cell infiltration. Using pretreatment RNA-seq data from 13 ICI-treated cohorts, we validated the use of MOTIF in predicting CD8+ T cell infiltration and ICI efficacy. Among the components of MOTIF, we identified EMC3 as a negative regulator of CD8+ T cell infiltration, which was validated via in vivo studies. Additionally, MOTIF provided guidance for the potential combinations of programmed death 1 blockade with certain immunostimulatory drugs to facilitate CD8+ T cell infiltration and improve ICI efficacy.

Cellular interactions in tumor microenvironment during breast cancer progression: new frontiers and implications for novel therapeutics

The breast cancer tumor microenvironment (TME) is dynamic, with various immune and non-immune cells interacting to regulate tumor progression and anti-tumor immunity. It is now evident that the cells within the TME significantly contribute to breast cancer progression and resistance to various conventional and newly developed anti-tumor therapies. Both immune and non-immune cells in the TME play critical roles in tumor onset, uncontrolled proliferation, metastasis, immune evasion, and resistance to anti-tumor therapies. Consequently, molecular and cellular components of breast TME have emerged as promising therapeutic targets for developing novel treatments. The breast TME primarily comprises cancer cells, stromal cells, vasculature, and infiltrating immune cells. Currently, numerous clinical trials targeting specific TME components of breast cancer are underway. However, the complexity of the TME and its impact on the evasion of anti-tumor immunity necessitate further research to develop novel and improved breast cancer therapies. The multifaceted nature of breast TME cells arises from their phenotypic and functional plasticity, which endows them with both pro and anti-tumor roles during tumor progression. In this review, we discuss current understanding and recent advances in the pro and anti-tumoral functions of TME cells and their implications for developing safe and effective therapies to control breast cancer progress.

Tertiary lymphoid structures in cancer: immune mechanisms and clinical implications

Cancer is a major cause of death globally, and traditional treatments often have limited efficacy and adverse effects. Immunotherapy has shown promise in various malignancies but is less effective in tumors with low immunogenicity or immunosuppressive microenvironment, especially sarcomas. Tertiary lymphoid structures (TLSs) have been associated with a favorable response to immunotherapy and improved survival in cancer patients. However, the immunological mechanisms and clinical significance of TLS in malignant tumors are not fully understood. In this review, we elucidate the composition, neogenesis, and immune characteristics of TLS in tumors, as well as the inflammatory response in cancer development. An in-depth discussion of the unique immune characteristics of TLSs in lung cancer, breast cancer, melanoma, and soft tissue sarcomas will be presented. Additionally, the therapeutic implications of TLS, including its role as a marker of therapeutic response and prognosis, and strategies to promote TLS formation and maturation will be explored. Overall, we aim to provide a comprehensive understanding of the role of TLS in the tumor immune microenvironment and suggest potential interventions for cancer treatment.

Ultrasound combined with microbubble mediated immunotherapy for tumor microenvironment

The tumor microenvironment (TME) plays an important role in dynamically regulating the progress of cancer and influencing the therapeutic results. Targeting the tumor microenvironment is a promising cancer treatment method in recent years. The importance of tumor immune microenvironment regulation by ultrasound combined with microbubbles is now widely recognized. Ultrasound and microbubbles work together to induce antigen release of tumor cell through mechanical or thermal effects, promoting antigen presentation and T cells' recognition and killing of tumor cells, and improve tumor immunosuppression microenvironment, which will be a breakthrough in improving traditional treatment problems such as immune checkpoint blocking (ICB) and himeric antigen receptor (CAR)-T cell therapy. In order to improve the therapeutic effect and immune regulation of TME targeted tumor therapy, it is necessary to develop and optimize the application system of microbubble ultrasound for organs or diseases. Therefore, the combination of ultrasound and microbubbles in the field of TME will continue to focus on developing more effective strategies to regulate the immunosuppression mechanisms, so as to activate anti-tumor immunity and/or improve the efficacy of immune-targeted drugs, At present, the potential value of ultrasound combined with microbubbles in TME targeted therapy tumor microenvironment targeted therapy has great potential, which has been confirmed in the experimental research and application of breast cancer, colon cancer, pancreatic cancer and prostate cancer, which provides a new alternative idea for clinical tumor treatment. This article reviews the research progress of ultrasound combined with microbubbles in the treatment of tumors and their application in the tumor microenvironment.

Predictive indicators of immune therapy efficacy in hepatocellular carcinoma based on neutrophil-to-lymphocyte ratio

Hepatocellular carcinoma (HCC) exhibits high incidence and mortality rates in China. Most cases are often diagnosed at late stages and require multi-strategy therapies. In recent years, immune checkpoint inhibitors (ICIs), particularly programmed cell death protein 1 (PD-1) antibodies, have demonstrated effectiveness in comprehensive HCC treatment. However, the efficacy and prognosis vary greatly among patients. Screening suitable patients and predicting outcomes are crucial for improving the efficacy of ICIs. Although PD-L1 expression levels in tumor cells have been used as predictors of PD-1/PD-L1 antibody therapy, they may not consistently correlate with clinical response in some studies; thus, exploring new biomarkers is necessary. The neutrophil-to-lymphocyte ratio (NLR) emerged as a new predictor of ICI immunotherapy efficacy, and its application in HCC is worth exploring. This study utilizes the Cancer Genome Atlas Liver Hepatocellular Carcinoma Collection (TCGA-LIHC) project in the Genomic Data Commons (GDC) database for methylation and transcriptome data analysis. The correlation between NLR and ICI immunotherapy efficacy for HCC was evaluated, identifying differentially expressed genes. Analysis revealed 74 up-regulated and 445 down-regulated genes in the high-NLR group compared to the low-NLR group. NLR-related differential methylation analysis identified 68 hypermethylated and 65 hypomethylated probes in the NLR high group. Furthermore, a machine learning model using 27 intersecting genes predicted PD-1 antibody therapy efficacy, achieving an AUC value of 0.813. In summary, we established a predictive model for HCC immunotherapy based on 27 genes related to differential expressions and NLR-associated methylation, showing significant potential for clinical research potential in this field.

Motility and tumor infiltration are key aspects of invariant natural killer T cell anti-tumor function

Dysfunction of invariant natural killer T (iNKT) cells contributes to immune resistance of tumors. Most mechanistic studies focus on their static functional status before or after activation, not considering motility as an important characteristic for antigen scanning and thus anti-tumor capability. Here we show via intravital imaging, that impaired motility of iNKT cells and their exclusion from tumors both contribute to the diminished anti-tumor iNKT cell response. Mechanistically, CD1d, expressed on macrophages, interferes with tumor infiltration of iNKT cells and iNKT-DC interactions but does not influence their intratumoral motility. VCAM1, expressed by cancer cells, restricts iNKT cell motility and inhibits their antigen scanning and activation by DCs via reducing CDC42 expression. Blocking VCAM1-CD49d signaling improves motility and activation of intratumoral iNKT cells, and consequently augments their anti-tumor function. Interference with macrophage-iNKT cell interactions further enhances the anti-tumor capability of iNKT cells. Thus, our findings provide a direction to enhance the efficacy of iNKT cell-based immunotherapy via motility regulation.

Immune signatures of checkpoint inhibitor-induced autoimmunity-A focus on neurotoxicity

BACKGROUND

Neurologic immune-related adverse events (irAE-n) are rare but severe toxicities of immune checkpoint inhibitor (ICI) treatment. To overcome diagnostic and therapeutic challenges, a better mechanistic understanding of irAE-n is paramount.

METHODS

In this observational cohort study, we collected serum and peripheral blood samples from 34 consecutive cancer patients with irAE-n (during acute illness) and 49 cancer control patients without irAE-n (pre- and on-ICI treatment, n = 44 without high-grade irAEs, n = 5 with high-grade nonneurologic irAEs). Patients received either anti-programmed cell death protein (PD)-1 or anti-PD ligand-1 monotherapy or anti-PD-1/anti-cytotoxic T-lymphocyte-associated protein-4 combination therapy. Most common cancers were melanoma, lung cancer, and hepatocellular carcinoma. Peripheral blood immune profiling was performed using 48-marker single-cell mass cytometry and a multiplex cytokine assay.

RESULTS

During acute illness, patients with irAE-n presented higher frequencies of cluster of differentiation (CD)8+ effector memory type (EM-)1 and central memory (CM) T cells compared to controls without irAEs. Multiorgan immunotoxicities (neurologic + nonneurologic) were associated with higher CD8+ EM1 T cell counts. While there were no B cell changes in the overall cohort, we detected a marked decrease of IgD- CD11c+ CD21low and IgD- CD24+ CD21high B cells in a subgroup of patients with autoantibody-positive irAE-n. We further identified signatures indicative of enhanced chemotaxis and inflammation in irAE-n patients and discovered C-X-C motif chemokine ligand (CXCL)10 as a promising marker to diagnose high-grade immunotoxicities such as irAE-n.

CONCLUSIONS

We demonstrate profound and partly subgroup-specific immune cell dysregulation in irAE-n patients, which may guide future biomarker development and targeted treatment approaches.

TAM-Hijacked Immunoreaction Rescued by Hypoxia-Pathway-Intervened Strategy for Enhanced Metastatic Cancer Immunotherapy

Immunotherapy is regarded as a prospective strategy against metastatic cancer. However, tumor-associated macrophages (TAMs), which accumulate in hypoxic tumor microenvironment, reduce the effectiveness of immunotherapy by blocking or "hijacking" the initiation of the immune response. Here, a novel tumor-targeted nanoplatform loaded with hypoxia-pathway-intervened docosahexaenoic acid (DHA) and chemotherapeutic drug carfilzomib (CFZ) is developed, which realizes the rescue of TAM-hijacked immune response and effective metastatic cancer immunotherapy. DHA is conjugated to fucoidan (Fuc) via a reduction cleavable selenylsulfide bond (SSe) for micelle preparation, and CFZ is encapsulated in the hydrophobic cores of micelles. The functionalized nanoplatforms (Fuc─SSe─DHA (FSSeD)-CFZs) induce immunogenic cell death, inhibit hypoxia-inducible factor-1α expression, and improve immunosuppression by TAM suppression. FSSeD-CFZs enhance immune response against primary tumor development and metastasis formation. In brief, the novel rescue strategy for TAM-hijacked immunoreaction by inhibiting hypoxia pathway has the potential and clinically translational significance for enhanced metastatic cancer immunotherapy.

Downregulation of ST6GAL2 Correlates to Liver Inflammation and Predicts Adverse Prognosis in Hepatocellular Carcinoma

Purpose

ST6 Beta-Galactoside Alpha-2,6-Sialyltransferase 2 (ST6GAL2), a member of the sialic acid transferase family, is differentially expressed in diverse cancers. However, it remains poorly understood in tumorigenesis and impacts on immune cell infiltration (ICI) in hepatocellular carcinoma (HCC).

Patients and Methods

Herein, the expression, diagnosis, prognosis, functional enrichment, genetic alterations, immune characteristics, and targeted drugs of ST6GAL2 in HCC were researched by conducting bioinformatics analysis, in vivo, and in vitro experiments.

Results

ST6GAL2 was remarkably decreased in HCC compared to non-tumor tissues, portending a poor prognosis associated with high DNA methylation levels. Functional enrichment and GSVA analyses revealed that ST6GAL2 might function through the extracellular matrix, PI3K-Akt signaling pathways, and tumor inflammation signature. We found that ST6GAL2 expression was proportional to ICI, immunostimulator, and immune subtypes. ST6GAL2 expression first increased and then decreased during the progression of liver inflammation to HCC. The dysfunctional experiment indicated that ST6GAL2 might exert immunosuppressive effects during HCC progression through regulating ICI. Several broad-spectrum anticancer drugs were obtained by drug sensitivity prediction analysis of ST6GAL2.

Conclusion

In conclusion, ST6GAL2 was a reliable prognostic biomarker strongly associated with ICI, and could be a potential immunotherapeutic target for HCC.

Decoding the Tumour Microenvironment: Molecular Players, Pathways, and Therapeutic Targets in Cancer Treatment

The tumour microenvironment (TME) is a complex and constantly evolving collection of cells and extracellular components. Cancer cells and the surrounding environment influence each other through different types of processes. Characteristics of the TME include abnormal vasculature, altered extracellular matrix, cancer-associated fibroblast and macrophages, immune cells, and secreted factors. Within these components, several molecules and pathways are altered and take part in the support of the tumour. Epigenetic regulation, kinases, phosphatases, metabolic regulators, and hormones are some of the players that influence and contribute to shaping the tumour and the TME. All these characteristics contribute significantly to cancer progression, metastasis, and immune escape, and may be the target for new approaches for cancer treatment.

Disulfidptosis status influences prognosis and therapeutic response in clear cell renal cell carcinoma

Disulfidptosis is a recently identified type of programmed cell death. It is characterized by aberrant accumulation of intracellular disulfides. The clinical implications of disulfidptosis in clear cell renal cell carcinoma (ccRCC) remain unclear. A series of bioinformatics approaches were employed to analyze ten disulfidptosis-related molecules. Firstly, the expression patterns of the disulfidptosis-related molecules were different between normal and ccRCC tissues. A comprehensive cohort of patients with ccRCC was then assembled from three public databases and subjected to cluster analysis based on disulfidptosis-related molecules. Consensus cluster analysis revealed three distinct disulfidptosis clusters. We then conducted weighted gene co-expression network analysis (WGCNA) to identify highly correlated genes. 267 hub genes were screened out through WGCNA, and three gene clusters were then determined. Finally, we identified 87 genes with prognostic value and then used them to develop a disulfidptosis scoring (DSscore) system, which was proven to independently predict survival in ccRCC. Patients in the high-DSscore group exhibited a significant survival advantage and better immunotherapeutic responses compared with those in the low-DSscore group. However, the patients in the low-DSscore group exhibited a greater degree of chemotherapeutic response. In addition, the expression of disulfidptosis-related molecules was validated by qRT-PCR, and the potential of disulfidptosis-related molecules to indicate distinct cell subtypes were validated by single-cell RNA-sequencing. In conclusion, DSscore is a promising index for predicting the prognosis and efficacy of immunotherapy in patients with ccRCC and may provide a basis for novel strategies for future studies.

What role does GPR65 play in the progression of osteosarcoma? Its mechanism and clinical significance

BACKGROUND

GPR65 is a pH-sensing G-protein-coupled receptor that acts as a key innate immune checkpoint in the human tumor microenvironment, inhibiting the release of inflammatory factors and inducing significant upregulation of tissue repair genes. However, the expression pattern and function of GPR65 in osteosarcoma (OS) remain unclear. The purpose of this study was to investigate and elucidate the role of GPR65 in the microenvironment, proliferation and migration of OS.

METHODS

Retrospective RNA-seq data analysis was conducted in a cohort of 97 patients with OS data in the TAEGET database. In addition, single-cell sequencing data from six surgical specimens of human OS patients was used to analyze the molecular evolution process during OS genesis. Tissues chips and bioinformatics results were used to verify GPR65 expression level in OS. MTT, colony formation, EdU assay, wound healing, transwell assay and F-actin assay were utilized to analyze cell proliferation and invasion of OS cancer cells. RNA-seq was used to explore the potential mechanism of GPR65's role in OS.

RESULTS

GPR65 expression was significantly low in OS, and subgroup analysis found that younger OS patients, OS patients in metastatic status, and overall survival and progression free survival OS patients had lower GPR65 expression. From ScRNA-seq data of GSE162454, we found the expression of GPR65 is significantly positively correlated with CD4 + T cells CD8 + T cells and OS related macrophage infiltration. Verification experiment found that silencing the expression of GPR65 in osteosarcoma cells U2OS and HOS could promote the proliferation and invasion process, RNA-seq results showed that the role of GPR65 in OS cells was related to immune system, metabolism and signal transduction.

CONCLUSION

The low expression of GPR65 in OS leads to high metastasis rate and poor prognosis in OS patients. The suppression of immune escape and inhibition of proliferation may be a key pathway for GPR65 to participate in the progression of OS. The current study strengthens the role of GPR65 in OS development and provides a potential biomarker for the prognosis of OS patients.

Microbial metabolites are involved in tumorigenesis and development by regulating immune responses

The human microbiota is symbiotic with the host and can create a variety of metabolites. Under normal conditions, microbial metabolites can regulate host immune function and eliminate abnormal cells in a timely manner. However, when metabolite production is abnormal, the host immune system might be unable to identify and get rid of tumor cells at the early stage of carcinogenesis, which results in tumor development. The mechanisms by which intestinal microbial metabolites, including short-chain fatty acids (SCFAs), microbial tryptophan catabolites (MTCs), polyamines (PAs), hydrogen sulfide, and secondary bile acids, are involved in tumorigenesis and development by regulating immune responses are summarized in this review. SCFAs and MTCs can prevent cancer by altering the expression of enzymes and epigenetic modifications in both immune cells and intestinal epithelial cells. MTCs can also stimulate immune cell receptors to inhibit the growth and metastasis of the host cancer. SCFAs, MTCs, bacterial hydrogen sulfide and secondary bile acids can control mucosal immunity to influence the occurrence and growth of tumors. Additionally, SCFAs, MTCs, PAs and bacterial hydrogen sulfide can also affect the anti-tumor immune response in tumor therapy by regulating the function of immune cells. Microbial metabolites have a good application prospect in the clinical diagnosis and treatment of tumors, and our review provides a good basis for related research.

Implications of different cell death patterns for prognosis and immunity in lung adenocarcinoma

In recent years, lung adenocarcinoma (LUAD) has become a focus of attention due to its low response to treatment, poor prognosis, and lack of reliable indicators to predict the progression or therapeutic effect of LUAD. Different cell death patterns play a crucial role in tumor development and are promising for predicting LUAD prognosis. From the TCGA and GEO databases, we obtained bulk transcriptomes, single-cell transcriptomes, and clinical information. Genes in 15 types of cell death were analyzed for cell death index (CDI) signature establishment. The CDI signature using necroptosis + immunologic cell death-related genes was established in the TCGA cohort with the 1-, 2-, 3-, 4- and 5-year AUC values were 0.772, 0.736, 0.723, 0.795, and 0.743, respectively. The prognosis was significantly better in the low CDI group than in the high CDI group. We also investigated the relationship between the CDI signature and clinical variables, published prognosis biomarkers, immune cell infiltration, functional enrichment pathways, and immunity biomarkers. In vitro assay showed that HNRNPF and FGF2 promoted lung cancer cell proliferation and migration and were also involved in cell death. Therefore, as a robust prognosis biomarker, CDI signatures can screen for patients who might benefit from immunotherapy and improve diagnostic accuracy and LUAD patient outcomes.

Implications of single-cell immune landscape of tumor microenvironment for the colorectal cancer diagnostics and therapy

Colorectal cancer (CRC) originates from the polyps lining the colon and is among the most common types of cancer. With the increasing popularity of single-cell sequencing technologies, researchers have been able to better understand the immune landscape of colorectal cancer, by analyzing their expression and interactions in detail with the tumor microenvironment (TME) at single-cell level. Since the tumor-immune cell interactions play a critical part in the advancement as well as treatment response in colorectal cancer, the release of inhibitory factors such as T cells are important for recognizing and destroying cancer cells. Such information is vital to identify immunotherapeutic targets for cure and monitoring response to treatments. Therefore, a comprehensive single-cell studies-based overview of key immunogenic agents regulating the TME of CRC is provided in this review. Tumor-associated macrophages can promote tumor growth and resistance to treatment by releasing factors that inhibit the function of other immune cells. Additionally, colorectal cancer cells can express programmed cell death protein 1 and its ligand, which can also inhibit T-cell function. Researchers have found that certain types of immune cells, prominently T cells, natural killer, and dendritic cells, can have a positive impact on the prognosis of colorectal cancer patients. Treatments like immune checkpoint inhibitors and CAR-T therapies that help to release the inhibitory signals from the cancer cells allow the immune cells to function more effectively.

Crosstalk between gut microbiota and metastasis in colorectal cancer: implication of neutrophil extracellular traps

Primary colorectal cancer (CRC) often leads to liver metastasis, possibly due to the formation of pre-metastatic niche (PMN) in liver. Thus, unravelling the key modulator in metastasis is important for the development of clinical therapies. Gut microbiota dysregulation is a key event during CRC progression and metastasis. Numerous studies have elucidated the correlation between specific gut bacteria strains (e.g., pks + E. coli and Bacteroides fragilis) and CRC initiation, and gut bacteria translocation is commonly witnessed during CRC progression. Gut microbiota shapes tumor microenvironment (TME) through direct contact with immune cells or through its functional metabolites. However, how gut microbiota facilitates CRC metastasis remains controversial. Meanwhile, recent studies identify the dissemination of bacteria from gut lumen to liver, suggesting the role of gut microbiota in shaping tumor PMN. A pro-tumoral PMN is characterized by the infiltration of immunosuppressive cells and increased pro-inflammatory immune responses. Notably, neutrophils form web-like structures known as neutrophil extracellular traps (NETs) both in primary TME and metastatic sites, NETs are involved in cancer progression and metastasis. In this review, we focus on the role of gut microbiota in CRC progression and metastasis, highlight the multiple functions of different immune cell types in TME, especially neutrophils and NETs, discuss the possible mechanisms of gut microbiota in shaping PMN formation, and provide therapeutical indications in clinic.

Oncolytic virus M1 functions as a bifunctional checkpoint inhibitor to enhance the antitumor activity of DC vaccine

Although promising, dendritic cell (DC) vaccines still provide limited clinical benefits, mainly due to the immunosuppressive tumor microenvironment (TME) and the lack of tumor-associated antigens (TAAs). Oncolytic virus therapy is an ideal strategy to overcome immunosuppression and expose TAAs; therefore, they may work synergistically with DC vaccines. In this study, we demonstrate that oncolytic virus M1 (OVM) can enhance the antitumor effects of DC vaccines across diverse syngeneic mouse tumor models by increasing the infiltration of CD8+ effector T cells in the TME. Mechanically, we show that tumor cells counteract DC vaccines through the SIRPα-CD47 immune checkpoint, while OVM can downregulate SIRPα in DCs and CD47 in tumor cells. Since OVM upregulates PD-L1 in DCs, combining PD-L1 blockade with DC vaccines and OVM further enhances antitumor activity. Overall, OVM strengthens the antitumor efficacy of DC vaccines by targeting the SIRPα-CD47 axis, which exerts dominant immunosuppressive effects on DC vaccines.

Multi-omics analysis reveals the involvement of origin recognition complex subunit 6 in tumor immune regulation and malignant progression

Background

Origin recognition complex 6 (ORC6) is one of the six highly conserved subunit proteins required for DNA replication and is essential for maintaining genome stability during cell division. Recent research shows that ORC6 regulates the advancement of multiple cancers; however, it remains unclear what regulatory impact it has on the tumor immune microenvironment.

Methods

Unpaired Wilcoxon rank sum and signed rank tests were used to analyze the differences in the expression of ORC6 in normal tissues and corresponding tumor tissues. Multiple online databases have evaluated the genetic alterations, protein expression and localization, and clinical relevance of ORC6. To evaluate the potential prognostic impact and diagnostic significance of ORC6 expression, we carried out log-rank, univariate Cox regression, and receiver operating characteristic curve analysis. The ICGC-LIRI-JP cohort, CGGA-301 cohort, CGGA-325 cohort, CGGA-693 cohort, and GSE13041 cohort were used for external validation of the study findings. The associations between ORC6 expression and immune cell infiltration, immune checkpoint expression, and immunotherapy cohorts was further analyzed. To explore the functional and signaling pathways related to ORC6 expression, gene set enrichment analysis was performed. To clarify the expression and function of ORC6 in hepatocellular carcinoma (LIHC) and glioma, we conducted in vitro experiments.

Results

Expression of ORC6 is upregulated in the majority of cancer types and is associated with poor patient prognosis, notably in cases of LIHC and gliomas. In addition, ORC6 may be involved in multiple signaling pathways related to cancer progression and immune regulation. High expression of ORC6 correlates with an immunosuppressive state in the tumor microenvironment. The results of further immunotherapy cohort analysis suggested that patients in the ORC6 high-expression group benefited from immunotherapy. Inhibiting ORC6 expression suppressed the proliferative and migratory abilities of LIHC and glioma cells.

Conclusion

High expression of ORC6 may be used as a biomarker to predict the poor prognosis of most tumor patients. The high expression of ORC6 may be involved in the regulation of the tumor immunosuppressive environment, and it is expected to become a molecular target for inhibiting tumor progression.

Define cancer-associated fibroblasts (CAFs) in the tumor microenvironment: new opportunities in cancer immunotherapy and advances in clinical trials

Despite centuries since the discovery and study of cancer, cancer is still a lethal and intractable health issue worldwide. Cancer-associated fibroblasts (CAFs) have gained much attention as a pivotal component of the tumor microenvironment. The versatility and sophisticated mechanisms of CAFs in facilitating cancer progression have been elucidated extensively, including promoting cancer angiogenesis and metastasis, inducing drug resistance, reshaping the extracellular matrix, and developing an immunosuppressive microenvironment. Owing to their robust tumor-promoting function, CAFs are considered a promising target for oncotherapy. However, CAFs are a highly heterogeneous group of cells. Some subpopulations exert an inhibitory role in tumor growth, which implies that CAF-targeting approaches must be more precise and individualized. This review comprehensively summarize the origin, phenotypical, and functional heterogeneity of CAFs. More importantly, we underscore advances in strategies and clinical trials to target CAF in various cancers, and we also summarize progressions of CAF in cancer immunotherapy.

Synergist for antitumor therapy: Astragalus polysaccharides acting on immune microenvironment

Various new treatments are emerging constantly in anti-tumor therapies, including chemotherapy, immunotherapy, and targeted therapy. However, the efficacy is still not satisfactory. Astragalus polysaccharide is an important bioactive component derived from the dry root of Radix astragali. Studies found that astragalus polysaccharides have gained great significance in increasing the sensitivity of anti-tumor treatment, reducing the side effects of anti-tumor treatment, reversing the drug resistance of anti-tumor drugs, etc. In this review, we focused on the role of astragalus polysaccharides in tumor immune microenvironment. We reviewed the immunomodulatory effect of astragalus polysaccharides on macrophages, dendritic cells, natural killer cells, T lymphocytes, and B lymphocytes. We found that astragalus polysaccharides can promote the activities of macrophages, dendritic cells, natural killer cells, T lymphocytes, and B lymphocytes and induce the expression of a variety of cytokines and chemokines. Furthermore, we summarized the clinical applications of astragalus polysaccharides in patients with digestive tract tumors. We summarized the effective mechanism of astragalus polysaccharides on digestive tract tumors, including apoptosis induction, proliferation inhibition, immunoactivity regulation, enhancement of the anticancer effect and chemosensitivity. Therefore, in view of the multiple functions of astragalus polysaccharides in tumor immune microenvironment and its clinical efficacy, the combination of astragalus polysaccharides with antitumor therapy such as immunotherapy may provide new sparks to the bottleneck of current treatment methods.

Whole tumour cell-based vaccines: tuning the instruments to orchestrate an optimal antitumour immune response

Immunotherapy, particularly those based on immune checkpoint inhibitors (ICIs), has become a useful approach for many neoplastic diseases. Despite the improvements of ICIs in supporting tumour regression and prolonging survival, many patients do not respond or develop resistance to treatment. Thus, therapies that enhance antitumour immunity, such as anticancer vaccines, constitute a feasible and promising therapeutic strategy. Whole tumour cell (WTC) vaccines have been extensively tested in clinical studies as intact or genetically modified cells or tumour lysates, injected directly or loaded on DCs with distinct adjuvants. The essential requirements of WTC vaccines include the optimal delivery of a broad battery of tumour-associated antigens, the presence of tumour cell-derived molecular danger signals, and adequate adjuvants. These factors trigger an early and robust local innate inflammatory response that orchestrates an antigen-specific and proinflammatory adaptive antitumour response capable of controlling tumour growth by several mechanisms. In this review, the strengths and weaknesses of our own and others' experiences in studying WTC vaccines are revised to discuss the essential elements required to increase anticancer vaccine effectiveness.

A novel disulfidptosis and glycolysis related risk score signature for prediction of prognosis and ICI therapeutic responsiveness in colorectal cancer

Disulfidptosis is a newly-identified non-programmed cell death mode with tight associations with glucose metabolism. Elevated glycolysis is an important metabolic feature of tumor cells, which fulfills the energy requirement for their rapid growth and progression. Our present study determined to develop a disulfidptosis and glycolysis related gene (DGRG) risk score signature to predict the prognosis and ICI therapeutic responsiveness for CRC patients. First, the gene expression and clinical profiles for CRC patients were obtained from TCGA and GEO database. Using weighted gene co-expression network analysis, we identified hub genes showing the strongest correlations with both disulfidptosis and glycolysis activities. Next, a DGRG risk score signature was successfully developed through univariate and least absolute shrinkage and selection operator method Cox regression method. A DGRG risk score-based nomogram could further enhance the predictive performance. In addition, an array of systemic analysis was performed to unravel the correlation of DGRG risk score with tumor microenvironment. The results showed that CRC patients with low DGRG risk level had up-regulated immune cell infiltrations, enhanced metabolic activities and heightened gene mutation frequencies, while high risk patients was the opposite. Moreover, our present study identified low risk CRC patients as potential beneficiaries from immune checkpoint inhibitor (ICI) therapies. Our present work highlighted the potential utility of DGRG risk score signature in prognosis prediction and ICI responsiveness determination for CRC patients, which demonstrated promising clinical application value.

Tumor-associated myeloid cells in cancer immunotherapy

Tumor-associated myeloid cells (TAMCs) are among the most important immune cell populations in the tumor microenvironment, and play a significant role on the efficacy of immune checkpoint blockade. Understanding the origin of TAMCs was found to be the essential to determining their functional heterogeneity and, developing cancer immunotherapy strategies. While myeloid-biased differentiation in the bone marrow has been traditionally considered as the primary source of TAMCs, the abnormal differentiation of splenic hematopoietic stem and progenitor cells, erythroid progenitor cells, and B precursor cells in the spleen, as well as embryo-derived TAMCs, have been depicted as important origins of TAMCs. This review article provides an overview of the literature with a focus on the recent research progress evaluating the heterogeneity of TAMCs origins. Moreover, this review summarizes the major therapeutic strategies targeting TAMCs with heterogeneous sources, shedding light on their implications for cancer antitumor immunotherapies.

The biological significance of cuproptosis-key gene MTF1 in pan-cancer and its inhibitory effects on ROS-mediated cell death of liver hepatocellular carcinoma

Metal regulatory transcription factor 1 (MTF1) has been reported to be correlated with several human diseases, especially like cancers. Exploring the underlying mechanisms and biological functions of MTF1 could provide novel strategies for clinical diagnosis and therapy of cancers. In this study, we conducted the comprehensive analysis to evaluate the profiles of MTF1 in pan-cancer. For example, TIMER2.0, TNMplot and GEPIA2.0 were employed to analyze the expression values of MTF1 in pan-cancer. The methylation levels of MTF1 were evaluated via UALCAN and DiseaseMeth version 2.0 databases. The mutation profiles of MTF1 in pan-cancers were analyzed using cBioPortal. GEPIA2.0, Kaplan-Meier plotter and cBioPortal were also used to explore the roles of MTF1 in cancer prognosis. We found that high MTF1 expression was related to poor prognosis of liver hepatocellular carcinoma (LIHC) and brain lower grade glioma (LGG). Also, high expression level of MTF1 was associated with good prognosis of kidney renal clear cell carcinoma (KIRC), lung cancer, ovarian cancer and breast cancer. We investigated the genetic alteration and methylation levels of MTF1 between the primary tumor and normal tissues. The relationship between MTF1 expression and several immune cells was analyzed, including T cell CD8 + and dendritic cells (DC). Mechanically, MTF1-interacted molecules might participate in the regulation of metabolism-related pathways, such as peptidyl-serine phosphorylation, negative regulation of cellular amide metabolic process and peptidyl-threonine phosphorylation. Single cell sequencing indicated that MTF1 was associated with angiogenesis, DNA repair and cell invasion. In addition, in vitro experiment indicated knockdown of MTF1 resulted in the suppressed cell proliferation, increased reactive oxygen species (ROS) and promoted cell death in LIHC cells HepG2 and Huh7. Taken together, this pan-cancer analysis of MTF1 has implicated that MTF1 could play an essential role in the progression of various human cancers.

Impaired function of dendritic cells within the tumor microenvironment

Dendritic cells (DCs), a class of professional antigen-presenting cells, are considered key factors in the initiation and maintenance of anti-tumor immunity due to their powerful ability to present antigen and stimulate T-cell responses. The important role of DCs in controlling tumor growth and mediating potent anti-tumor immunity has been demonstrated in various cancer models. Accordingly, the infiltration of stimulatory DCs positively correlates with the prognosis and response to immunotherapy in a variety of solid tumors. However, accumulating evidence indicates that DCs exhibit a significantly dysfunctional state, ultimately leading to an impaired anti-tumor immune response due to the effects of the immunosuppressive tumor microenvironment (TME). Currently, numerous preclinical and clinical studies are exploring immunotherapeutic strategies to better control tumors by restoring or enhancing the activity of DCs in tumors, such as the popular DC-based vaccines. In this review, an overview of the role of DCs in controlling tumor progression is provided, followed by a summary of the current advances in understanding the mechanisms by which the TME affects the normal function of DCs, and concluding with a brief discussion of current strategies for DC-based tumor immunotherapy.

Therapies Targeting Immune Cells in Tumor Microenvironment for Non-Small Cell Lung Cancer

The tumor microenvironment (TME) plays critical roles in immune modulation and tumor malignancies in the process of cancer development. Immune cells constitute a significant component of the TME and influence the migration and metastasis of tumor cells. Recently, a number of therapeutic approaches targeting immune cells have proven promising and have already been used to treat different types of cancer. In particular, PD-1 and PD-L1 inhibitors have been used in the first-line setting in non-small cell lung cancer (NSCLC) with PD-L1 expression ≥1%, as approved by the FDA. In this review, we provide an introduction to the immune cells in the TME and their efficacies, and then we discuss current immunotherapies in NSCLC and scientific research progress in this field.

Cancer/testis antigens: promising immunotherapy targets for digestive tract cancers

Digestive tract cancers, including esophageal, gastric, and colorectal cancers, are the major cause of death among cancer patients worldwide due to the heterogeneity of cancer cells, which limits the effectiveness of traditional treatment methods. Immunotherapy represents a promising treatment strategy for improving the prognosis of patients with digestive tract cancers. However, the clinical application of this approach is limited by the absence of optimal targets. Cancer/testis antigens are characterized by low or absent expression in normal tissues, but high expression in tumor tissues, making them an attractive target for antitumor immunotherapy. Recent preclinical trials have shown promising results for cancer/testis antigen-targeted immunotherapy in digestive cancer. However, practical problems and difficulties in clinical application remain. This review presents a comprehensive analysis of cancer/testis antigens in digestive tract cancers, covering their expression, function, and potential as an immunotherapy target. Additionally, the current state of cancer/testis antigens in digestive tract cancer immunotherapy is discussed, and we predict that these antigens hold great promise as an avenue for breakthroughs in the treatment of digestive tract cancers.

Tumor Microenvironment as a Therapeutic Target in Melanoma Treatment

The role of the tumor microenvironment in tumor growth and therapy has recently attracted more attention in research and drug development. The ability of the microenvironment to trigger tumor maintenance, progression, and resistance is the main cause for treatment failure and tumor relapse. Accumulated evidence indicates that the maintenance and progression of tumor cells is determined by components of the microenvironment, which include stromal cells (endothelial cells, fibroblasts, mesenchymal stem cells, and immune cells), extracellular matrix (ECM), and soluble molecules (chemokines, cytokines, growth factors, and extracellular vesicles). As a solid tumor, melanoma is not only a tumor mass of monolithic tumor cells, but it also contains supporting stroma, ECM, and soluble molecules. Melanoma cells are continuously in interaction with the components of the microenvironment. In the present review, we focus on the role of the tumor microenvironment components in the modulation of tumor progression and treatment resistance as well as the impact of the tumor microenvironment as a therapeutic target in melanoma.

Signaling pathways involved in the biological functions of dendritic cells and their implications for disease treatment

The ability of dendritic cells (DCs) to initiate and regulate adaptive immune responses is fundamental for maintaining immune homeostasis upon exposure to self or foreign antigens. The immune regulatory function of DCs is strictly controlled by their distribution as well as by cytokines, chemokines, and transcriptional programming. These factors work in conjunction to determine whether DCs exert an immunosuppressive or immune-activating function. Therefore, understanding the molecular signals involved in DC-dependent immunoregulation is crucial in providing insight into the generation of organismal immunity and revealing potential clinical applications of DCs. Considering the many breakthroughs in DC research in recent years, in this review we focused on three basic lines of research directly related to the biological functions of DCs and summarized new immunotherapeutic strategies involving DCs. First, we reviewed recent findings on DC subsets and identified lineage-restricted transcription factors that guide the development of different DC subsets. Second, we discussed the recognition and processing of antigens by DCs through pattern recognition receptors, endogenous/exogenous pathways, and the presentation of antigens through peptide/major histocompatibility complexes. Third, we reviewed how interactions between DCs and T cells coordinate immune homeostasis in vivo via multiple pathways. Finally, we summarized the application of DC-based immunotherapy for autoimmune diseases and tumors and highlighted potential research prospects for immunotherapy that targets DCs. This review provides a useful resource to better understand the immunomodulatory signals involved in different subsets of DCs and the manipulation of these immune signals can facilitate DC-based immunotherapy.

Type I interferon response in astrocytes promotes brain metastasis by enhancing monocytic myeloid cell recruitment

Cancer metastasis to the brain is a significant clinical problem. Metastasis is the consequence of favorable interactions between invaded cancer cells and the microenvironment. Here, we demonstrate that cancer-activated astrocytes create a sustained low-level activated type I interferon (IFN) microenvironment in brain metastatic lesions. We further confirm that the IFN response in astrocytes facilitates brain metastasis. Mechanistically, IFN signaling in astrocytes activates C-C Motif Chemokine Ligand 2 (CCL2) production, which further increases the recruitment of monocytic myeloid cells. The correlation between CCL2 and monocytic myeloid cells is confirmed in clinical brain metastasis samples. Lastly, genetically or pharmacologically inhibiting C-C Motif Chemokine Receptor 2 (CCR2) reduces brain metastases. Our study clarifies a pro-metastatic effect of type I IFN in the brain even though IFN response has been considered to have anti-tumor effects. Moreover, this work expands our understandings on the interactions between cancer-activated astrocytes and immune cells in brain metastasis.

Ferroptosis, necroptosis, and pyroptosis in cancer: Crucial cell death types in radiotherapy and post-radiotherapy immune activation

Tumor cell death and antitumor immune activation induced by radiotherapy are extensively well-studied. While radiotherapy is believed to mainly induce tumor cell necrosis and apoptosis, recent studies have shown that it can also induce ferroptosis, necroptosis, and pyroptosis in tumor cells. However, studies on the role of ferroptosis, necroptosis, and pyroptosis in radiotherapy and post-radiotherapy immune activation are limited. In this review, we summarize the comprehensive literature on the molecular mechanisms and more recent research progress related to radiotherapy-induced ferroptosis, necroptosis, and pyroptosis in tumor cells. Further, we discuss the role of tumor cells undergoing these types of cell death in immune activation after radiotherapy. In addition, we highlight some unresolved questions on the association of radiotherapy with ferroptosis, necroptosis, and pyroptosis. This review can improve our current understanding of the relationship between radiotherapy and different cell death pathways and provide a theoretical framework to improve the therapeutic effect of tumor radiotherapy in the future.

Understanding the Tumor Immune Microenvironment in Renal Cell Carcinoma

Scientific understanding of how the immune microenvironment interacts with renal cell carcinoma (RCC) has substantially increased over the last decade as a result of research investigations and applying immunotherapies, which modulate how the immune system targets and eliminates RCC tumor cells. Clinically, immune checkpoint inhibitor therapy (ICI) has revolutionized the treatment of advanced clear cell RCC because of improved outcomes compared to targeted molecular therapies. From an immunologic perspective, RCC is particularly interesting because tumors are known to be highly inflamed, but the mechanisms underlying the inflammation of the tumor immune microenvironment are atypical and not well described. While technological advances in gene sequencing and cellular imaging have enabled precise characterization of RCC immune cell phenotypes, multiple theories have been suggested regarding the functional significance of immune infiltration in RCC progression. The purpose of this review is to describe the general concepts of the anti-tumor immune response and to provide a detailed summary of the current understanding of the immune response to RCC tumor development and progression. This article describes immune cell phenotypes that have been reported in the RCC microenvironment and discusses the application of RCC immunophenotyping to predict response to ICI therapy and patient survival.

Prognostic and Predictive Biomarkers in the Era of Immunotherapy for Lung Cancer

The therapeutic algorithm of lung cancer has recently been revolutionized by the emergence of immune checkpoint inhibitors. However, an objective and durable response rate remains low with those recent therapies and some patients even experience severe adverse events. Prognostic and predictive biomarkers are therefore needed in order to select patients who will respond. Nowadays, the only validated biomarker is the PD-L1 expression, but its predictive value remains imperfect, and it does not offer any certainty of a sustained response to treatment. With recent progresses in molecular biology, genome sequencing techniques, and the understanding of the immune microenvironment of the tumor and its host, new molecular features have been highlighted. There are evidence in favor of the positive predictive value of the tumor mutational burden, as an example. From the expression of molecular interactions within tumor cells to biomarkers circulating in peripheral blood, many markers have been identified as associated with the response to immunotherapy. In this review, we would like to summarize the latest knowledge about predictive and prognostic biomarkers of immune checkpoint inhibitors efficacy in order to go further in the field of precision immuno-oncology.

Cells of the tumor microenvironment speak the Wnt language

Wnt signaling plays numerous functions in cancer, from primary transformation and tumor growth to metastasis. In addition to these cancer cell-intrinsic functions, Wnt signaling emerges to critically control cross-communication among cancer cells and the tumor microenvironment (TME). Here, we summarize the evidence that not only multiple cancer cell types, but also cells constituting the TME 'speak the Wnt language'. Fibroblasts, macrophages, endothelia, and lymphocytes all use the Wnt language to convey messages to and from cancer cells and among themselves; these messages are important for tumor progression and fate. Decoding this language will advance our understanding of tumor biology and unveil novel therapeutic avenues.

Immunomodulatory effect of locoregional therapy in the tumor microenvironment

Cancer immunotherapy appears to be a promising treatment option; however, only a subset of patients with cancer responds favorably to treatment. Locoregional therapy initiates a local antitumor immune response by disrupting immunosuppressive components, releasing immunostimulatory damage-associated molecular patterns, recruiting immune effectors, and remodeling the tumor microenvironment. Many studies have shown that locoregional therapy can produce specific antitumor immunity alone; nevertheless, the effect is relatively weak and transient. Furthermore, increasing research efforts have explored the potential synergy between locoregional therapy and immunotherapy to enhance the long-term systemic antitumor immune effect and improve survival. Therefore, further research is needed into the immunomodulatory effects of locoregional therapy and immunotherapy to augment antitumor effects. This review article summarizes the key components of the tumor microenvironment, discusses the immunomodulatory role of locoregional therapy in the tumor microenvironment, and emphasizes the therapeutic potential of locoregional therapy in combination with immune checkpoint inhibitors.

Combined phospholipids adjuvant augments anti-tumor immune responses through activated tumor-associated dendritic cells

Dendritic cells (DCs) can initiate both naïve and memory T cell activation, as the most potent antigen-presenting cells. For efficient anti-tumor immunity, it is essential to enhance the anti-tumoral activity of tumor-associated DCs (TADCs) or to potently restrain TADCs so that they remain immuno-stimulating cells. Combined phospholipids (cPLs) adjuvant may act through the activation of DCs. This study demonstrated the potential mechanism of tumor growth inhibition of cPLs adjuvant, and confirmed that cPLs adjuvant could induce the maturation and activation (upregulation of MHC-II, CD80, CD40, IL-1β, IL-12, IL-6 expression) of BMDCs in vitro. Then we isolated tumor infiltrating lymphocytes (TILs) from solid tumor and analyzed the phenotype and cytokines of TILs. The examination of the TILs revealed that cPLs adjuvant upregulated the expression of co-stimulatory molecules (MHC-II, CD86), phosphatidylserine (PS) receptor (TIM-4) on TADCs and enhanced the cytotoxic effect (CD107a), as well as pro-inflammatory cytokine production (IFN-γ, TNF-α, IL-2) by the tumor-resident T cells. Taken together, cPLs adjuvant may be an immune-potentiating adjuvant for cancer immunotherapy. This reagent may lead to the development of new approaches in DC-targeted cancer immunotherapy.

Smart Nanoparticle-Based Platforms for Regulating Tumor Microenvironment and Cancer Immunotherapy

Tumor development and metastasis are closely related to the tumor microenvironment (TME). Recently, several studies indicate that modulating TME can enhance cancer immunotherapy. Among various approaches to modulating TME, nanoparticles (NPs) with unique inherent advantages and smart modified characteristics are promising candidates in delivering drugs to cancer cells, amplifying the therapeutic effects, and leading to a cascade of immune responses. In this review, several smart NP-based platforms are briefly introduced, such as responsive NPs, targeting NPs, and the composition of TME, including dendritic cells, macrophages, fibroblasts, endothelial cells, myeloid-derived suppressor cells, and regulatory T cells. Moreover, the recent applications of smart NP-based platforms in regulating TME and cancer immunotherapy are briefly introduced. Last, the advantages and disadvantages of these smart NP-based platforms in potential clinical translation are discussed.

Targeting Epigenetic Mechanisms: A Boon for Cancer Immunotherapy

Immunotherapy is rapidly emerging as a promising approach against cancer. In the last decade, various immunological mechanisms have been targeted to induce an increase in the immune response against cancer cells. However, despite promising results, many patients show partial response, resistance, or serious toxicities. A promising way to overcome this is the use of immunotherapeutic approaches, in combination with other potential therapeutic approaches. Aberrant epigenetic modifications play an important role in carcinogenesis and its progression, as well as in the functioning of immune cells. Thus, therapeutic approaches targeting aberrant epigenetic mechanisms and the immune response might provide an effective antitumor effect. Further, the recent development of potent epigenetic drugs and immunomodulators gives hope to this combinatorial approach. In this review, we summarize the synergy mechanism between epigenetic therapies and immunotherapy for the treatment of cancer, and discuss recent advancements in the translation of this approach.

The combination of oxaliplatin and anti-PD-1 inhibitor promotes immune cells infiltration and enhances anti-tumor effect of PD-1 blockade in bladder cancer

Introduction

Bladder cancer (BLCA) is a highly malignant tumor of the urinary system, but the prognosis and survival rates have little improvement based on current therapeutic strategy. Immune checkpoint inhibitors (ICIs) therapy revolutionized the treatment of BLCA, but the clinical application of ICIs is limited by low response rate. Oxaliplatin (OXP), a second line chemotherapy drug for BLCA, may reshape the tumor immune microenvironment (TIME) via recruiting immune cells. Here, we conducted the study of oxaliplatin combined with anti-PD-1 inhibitor in BLCA mice models.

Methods

The 6-8 weeks old female C57BL/6J mice were used to establish subcutaneous model of bladder tumor. After tumors developed, mice were given tail vein injections of PBS or oxaliplatin (2.5 mg/kg) and/or anti-PD-1 antibody (10 mg/kg). Tumor tissue samples and peripheral blood mononuclear cell (PBMC) were collected to systemically evaluate the efficiency and safety of combination OXP and anti-PD-1 inhibitor. The change of immune cells populations and the corresponding phenotypic diversity in TIME and PBMC were analysed by flow cytometry.

Results

Tumor growth experiments clarified that the combination therapy was more efficient than medication alone. Flow cytometry analysis of tumor samples showed significant differences between untreated and treated mice. Oxaliplatin influences the TIME by increasing immune cells infiltration, including CD3⁺ T cells, CD4⁺ T cells, CD8⁺ T cells, dendritic cells (DC cells) and natural killer cells (NK cells). As for infiltrating cells, oxaliplatin upregulated the expression of CD134 and downregulated TIM-3 of CD4⁺ T cells, downregulated the PD-L1 expression of DC cells, which contributed to improve the anti-tumor effect and the treatment response of ICIs. Additionally, the evaluation of PBMC found that there were no significant changes in immune cell subsets and phenotypes, which validated the safety of the combination therapy. These results show the therapeutic potential for the combination of OXP and anti-PD-1 inhibitor in BLCA.

Conclusion

OXP could increase the infiltration of immune cells in TIME to promote the anti-tumor activity of anti-PD-1 inhibitor. The present research provided an appropriate rationale of combination chemotherapy and immunotherapy therapy for BLCA.

Regulatory effects of IRF4 on immune cells in the tumor microenvironment

The tumor microenvironment (TME) is implicated in tumorigenesis, chemoresistance, immunotherapy failure and tumor recurrence. Multiple immunosuppressive cells and soluble secreted cytokines together drive and accelerate TME disorders, T cell immunodeficiency and tumor growth. Thus, it is essential to comprehensively understand the TME status, immune cells involved and key transcriptional factors, and extend this knowledge to therapies that target dysfunctional T cells in the TME. Interferon regulatory factor 4 (IRF4) is a unique IRF family member that is not regulated by interferons, instead, is mainly induced upon T-cell receptor signaling, Toll-like receptors and tumor necrosis factor receptors. IRF4 is largely restricted to immune cells and plays critical roles in the differentiation and function of effector cells and immunosuppressive cells, particularly during clonal expansion and the effector function of T cells. However, in a specific biological context, it is also involved in the transcriptional process of T cell exhaustion with its binding partners. Given the multiple effects of IRF4 on immune cells, especially T cells, manipulating IRF4 may be an important therapeutic target for reversing T cell exhaustion and TME disorders, thus promoting anti-tumor immunity. This study reviews the regulatory effects of IRF4 on various immune cells in the TME, and reveals its potential mechanisms, providing a novel direction for clinical immune intervention.

IDO1 Promotes the Progression of NSCLC by Regulating the Polarization of M2 Macrophages

Purpose

Non-small cell lung cancer (NSCLC) is currently a problem in the clinic and in society. Tumor-related macrophages (TAMs) in the tumor microenvironment (TME) play a vital role in the development of NSCLC.

Patients and Methods

Bioinformatics was used to analyze the role of Indoleamine 2,3-dioxygenase 1 (IDO1) in NSCLC and the correlation of its expression with CD163 expression. The expression of CD163 and IDO1 was measured by immunohistochemistry, and their colocalization was assessed by immunofluorescence. M2 macrophage polarization was induced, and a coculture model of NSCLC cells and macrophages was established.

Results

Bioinformatics analysis showed that IDO1 promoted the metastasis and differentiation of NSCLC and inhibited DNA repair. Moreover, the expression of IDO1 was positively correlated with CD163 expression. We discovered that IDO1 expression was related to M2 macrophage differentiation. In vitro, we showed that increased IDO1 expression promoted the invasion, proliferation, and metastasis of NSCLC cells.

Conclusion

In conclusion, we determined that IDO1 can regulate the M2 polarization of TAMs and promote the progression of NSCLC, which provides partial theoretical evidence for the use of IDO1 inhibitors in the treatment of NSCLC.