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Background and Purpose: Although our previous data indicated that claudin 18 isoform 2 (CLDN18.2)‐targeted chimeric antigen receptor (CAR) T cells displayed remarkable clinical efficacy in CLDN18.2‐positive gastric cancer, their efficacy is limited in pancreatic ductal adenocarcinoma (PDAC). The tumour microenvironment (TME) is one of the main obstacles to the efficacy of CAR‐T and remodelling the TME may be a possible way to overcome this obstacle. The TME of PDAC is characterized by abundant cancer‐related fibroblasts (CAFs), which hinder the infiltration and function of CLDN18.2‐targeted CAR‐T cells. The expression of fibroblast activation protein alpha (FAP) is an important feature of active CAFs, providing potential targets for eliminating CAFs. Experimental Approach: In this study, we generated 10 FAP/CLDN 18.2 dual‐targeted CAR‐T cells and evaluated their anti‐tumour ability in vitro and in vivo. Key Results: Compared with conventional CAR‐T cells, some dual‐targeted CAR‐T cells showed improved therapeutic effects in mouse pancreatic cancers. Further, dual‐targeted CAR‐T cells with better anti‐tumour effect could suppress the recruitment of myeloid‐derived suppressor cells (MDSCs) to improve the immunosuppressive TME, which contributes to the survival of CD8+ T cells. Moreover, dual‐targeted CAR‐T cells reduced the exhaustion of T cells in transforming TGF‐β dependent manner. Conclusion and Implications: The dual‐targeted CAR‐T cells obtained enhancement of T effector function, inhibition of T cell exhaustion, and improvement of tumour microenvironment. Our findings provide a theoretical rationale for dual‐targeted FAP/CLDN 18.2 CAR‐T cells therapy in PDAC. [ABSTRACT FROM AUTHOR]

The article discusses the successful treatment of a patient with refractory immune-mediated thrombotic thrombocytopenic purpura (iTTP) using daratumumab after multiple failed treatments, including splenectomy. Daratumumab, a humanized anti-CD38 antibody, has shown promise in treating refractory iTTP patients by rapidly increasing ADAMTS13 activity. The treatment led to a complete immunological response in most patients, with minimal adverse effects reported. The article highlights the potential of daratumumab as a promising option for multirefractory iTTP patients, although long-term efficacy and safety require further investigation. [Extracted from the article]

Background: Ubiquitination, a major post-translational modification, significantly impacts tumorigenesis, progression, and prognosis. This study aims to classify colon cancer at the molecular level and create a reliable signature using ubiquitination-related genes (URGs) to assess the immune microenvironment and prognosis. Methods: We employed non-negative matrix factorization to subtype colon cancer based on ubiquitination-related gene (URG) expression patterns. Quantitative scores for 28 immune cell infiltrates and the tumor microenvironment were computed using single-sample gene set enrichment analysis (ssGSEA) and the Estimate algorithm. Subtype feature genes were selected through Lasso logistic regression and SVM-RFE algorithm. The ubiquitination-related signature was constructed using univariate Cox, Lasso, and stepwise regression methods to categorize patients into high and low-risk groups. Validation included log-rank tests, receiver operating characteristic (ROC) analysis, decision curve analysis (DCA), and external dataset validation. Immune therapy response was compared using Tumor Immune Dysfunction and Exclusion (TIDE), Immunophenoscore (IPS), and submap analyses. Clinical variables and risk scores were integrated into an enhanced nomogram. The early diagnostic value of four URGs was confirmed via quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. The cell proliferation was assessed through colony formation, EdU staining, and xenograft tumorigenesis assays. Results: Prognostic ubiquitination-related genes (URGs) stratified patients into subtypes, revealing differences in survival, immune cell infiltration, and pathological staging. A signature of 6 URGs (ARHGAP4, MID2, SIAH2, TRIM45, UBE2D2, WDR72) was identified from 57 subtype-related genes. The high-risk group exhibited characteristics indicative of enhanced epithelial-mesenchymal transition, immune escape, immunosuppressive myeloid-derived suppressor cells, regulatory T cell infiltration, and lower immunogenicity. In contrast, the low-risk group demonstrated the opposite trend but showed a better response to CTLA4 checkpoint inhibitors. The predictive performance of the nomogram significantly improved with the integration of risk score, stage, and age ARHGAP4 and SIAH2 exhibit promising early diagnostic capabilities. Additionally, WDR72 knockdown significantly inhibited CRC cell proliferation both in vitro and in vivo. Conclusion: Our developed ubiquitination-related signature and genes serve as promising biomarkers for colon cancer prognosis, immune microenvironment, and diagnosis. [ABSTRACT FROM AUTHOR]

Background: In a previously reported Phase I trial, we observed therapy‐associated declines in circulating myeloid‐derived suppressor cells (MDSCs) with the administration of white button mushroom (WBM) tablets in prostate cancer (PCa) patients. These observations led us to hypothesise that WBM could mitigate PCa progression by suppressing MDSCs. Methods: We performed bidirectional translational research to examine the immunomodulatory effects of WBM consumption in both syngeneic murine PCa models and patients with PCa participating in an ongoing randomised Phase II trial (NCT04519879). Results: In murine models, WBM treatment significantly suppressed tumour growth with a reduction in both the number and function of MDSCs, which in turn promoted antitumour immune responses mediated by T cells and natural killer (NK) cells. In patients, after consumption of WBM tablets for 3 months, we observed a decline in circulating polymorphonuclear MDSCs (PMN‐MDSCs), along with an increase in cytotoxic CD8+ T and NK cells. Furthermore, single immune cell profiling of peripheral blood from WBM‐treated patients showed suppressed STAT3/IRF1 and TGFβ signalling in circulating PMN‐MDSCs. Subclusters of PMN‐MDSCs presented transcriptional profiles associated with responsiveness to fungi, neutrophil chemotaxis, leukocyte aggregation, and regulation of inflammatory response. Finally, in mouse models of PCa, we found that WBM consumption enhanced the anticancer activity of anti‐PD‐1 antibodies, indicating that WBM may be used as an adjuvant therapy with immune checkpoint inhibitors. Conclusion: Our results from PCa murine models and patients provide mechanistic insights into the immunomodulatory effects of WBM and provide a scientific foundation for WBM as a nutraceutical intervention to delay or prevent PCa progression. Highlights: White button mushroom (WBM) treatment resulted in a reduction in pro‐tumoural MDSCs, notably polymorphonuclear MDSCs (PMN‐MDSCs), along with activation of anti‐tumoural T and NK cells.Human single immune cell gene expression profiling shed light on the molecular alterations induced by WBM, specifically on PMN‐MDSCs.A proof‐of‐concept study combining WBM with PD‐1 blockade in murine models revealed an additive effect on tumour regression and survival outcomes, highlighting the clinical relevance of WBM in cancer management. [ABSTRACT FROM AUTHOR]

Tumor‐associated macrophages (TAMs) greatly contribute to immune checkpoint inhibitor (ICI) resistance of cancer. However, its underlying mechanisms and whether TAMs can be promising targets to overcome ICI resistance remain to be unveiled. Through integrative analysis of immune multiomics data and single‐cell RNA‐seq data (iMOS) in lung adenocarcinoma (LUAD), lymphotoxin β receptor (LTBR) is identified as a potential immune checkpoint of TAMs, whose high expression, duplication, and low methylation are correlated with unfavorable prognosis. Immunofluorescence staining shows that the infiltration of LTBR+ TAMs is associated with LUAD stages, immunotherapy failure, and poor prognosis. Mechanistically, LTΒR maintains immunosuppressive activity and M2 phenotype of TAMs by noncanonical nuclear factor kappa B and Wnt/β‐catenin signaling pathways. Macrophage‐specific knockout of LTBR hinders tumor growth and prolongs survival time via blocking TAM immunosuppressive activity and M2 phenotype. Moreover, TAM‐targeted delivery of LTΒR small interfering RNA improves the therapeutic effect of ICI via reversing TAM‐mediated immunosuppression, such as boosting cytotoxic CD8+ T cells and inhibiting granulocytic myeloid‐derived suppressor cells infiltration. Taken together, we bring forth an immune checkpoint discovery pipeline iMOS, identify LTBR as a novel immune checkpoint of TAMs, and propose a new immunotherapy strategy by targeting LTBR+ TAMs. Highlights: Integrative analysis of immune multiomics data and single‐cell RNA‐seq data pipeline is developed and finds lymphotoxin β receptor (LTBR) expression specific in tumor‐associated macrophages (TAMs).LTΒR+ TAMs correlate with lung adenocarcinoma stages, immunotherapy resistance, and prognosis.LTΒR maintains TAM immunosuppressive activity and M2 phenotype by noncanonical nuclear factor kappa B signaling and Wnt/β‐catenin signaling.Disruption of LTΒR in TAMs enhances the therapeutic effect of cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Background: Chimeric antigen receptor (CAR)‐T‐cell therapy has transformed cancer treatment, leading to remarkable clinical outcomes. However, resistance continues to be a major obstacle, significantly limiting its efficacy in numerous patients. Objectives: This review critically examines the challenges associated with CAR‐T‐cell therapy, with a particular focus on the role of apoptotic pathways in overcoming resistance. Methods: We explore various strategies to sensitize tumor cells to CAR‐T‐cell‐mediated apoptosis, including the use of combination therapies with BH3 mimetics, Mcl‐1 inhibitors, IAP inhibitors, and HDAC inhibitors. These agents inhibit anti‐apoptotic proteins and activate intrinsic mitochondrial pathways, enhancing the susceptibility of tumor cells to apoptosis. Moreover, targeting the extrinsic pathway can increase the expression of death receptors on tumor cells, further promoting their apoptosis. The review also discusses the development of novel CAR constructs that enhance anti‐apoptotic protein expression, such as Bcl‐2, which may counteract CAR‐T cell exhaustion and improve antitumor efficacy. We assess the impact of the tumor microenvironment (TME) on CAR‐T cell function and propose dual‐targeting CAR‐T cells to simultaneously address both myeloid‐derived suppressor cells (MDSCs) and tumor cells. Furthermore, we explore the potential of combining agents like PPAR inhibitors to activate the cGAS‐STING pathway, thereby improving CAR‐T cell infiltration into the tumor. Conclusions: This review highlights that enhancing tumor cell sensitivity to apoptosis and increasing CAR‐T cell cytotoxicity through apoptotic pathways could significantly improve therapeutic outcomes. Targeting apoptotic proteins, particularly those involved in the intrinsic mitochondrial pathway, constitutes a novel approach to overcoming resistance. The insights presented herein lay a robust foundation for future research and clinical applications aimed at optimizing CAR‐T cell therapies. [ABSTRACT FROM AUTHOR]

Background and Aim: Primary liver cancer, particularly hepatocellular carcinoma (HCC), represents a substantial global health challenge. Although immune checkpoint inhibitors are effective in HCC treatment, several patients still experience disease progression. Interleukin‐1 (IL‐1) regulates immunity and inflammation. We investigate the role of IL‐1 in HCC development and progression and determine the potential therapeutic impact of gemcitabine in treating HCC. Methods: Hydrodynamics‐based transfection, employing the sleeping beauty transposase system, delivered surrogate tumor antigens, NRAS (NRAS proto‐oncogene, GTPase), ShP53, and SB100 to C57BL/6 mice. A basic HCC mouse model was established. Pathogen‐free animals were tested for serum and hepatotoxicity. The HCC prognosis was monitored using alanine aminotransferase and aspartate aminotransferase levels. Liver histology immunohistochemistry and mouse splenocyte/intra‐hepatic immune cell flow cytometry were conducted. IL‐1β levels in human and mouse serum were assessed. Results: Interleukin‐1β levels were elevated in patients with HCC compared with those in non‐HCC controls. Hepatic IL‐1β levels were higher in HCC mouse models than those in non‐HCC mice, suggesting localized hepatic inflammation. IL‐1 receptor type 1 (IL‐1R1) knockout (IL‐1R1−/−) mice exhibited less severe HCC progression than that in wild‐type mice, despite the high intra‐hepatic IL‐1β concentration. IL‐1R1−/− mice exhibited increased hepatic levels of myeloid‐derived suppressor cells and regulatory T cells, which may exacerbate HCC. Gemcitabine significantly reduced the HCC tumor burden, improved liver conditions, and increased survival rates in HCC mouse models. Gemcitabine reduced the hepatic levels of myeloid‐derived suppressor cells and regulatory T cells, potentially alleviating immune suppression in the liver. Conclusions: Targeting IL‐1 or combining gemcitabine with immunotherapy is a promising approach for treating advanced‐stage HCC. [ABSTRACT FROM AUTHOR]

Patients diagnosed with advanced osteosarcoma, often in the form of lung metastases, have abysmal five-year overall survival rates. The complexity of the osteosarcoma immune tumor microenvironment has been implicated in clinical trial failures of various immunotherapies. The purpose of this exploratory study was to spatially characterize the immune tumor microenvironment of metastatic osteosarcoma lung specimens. Knowledge of the coordinating cellular networks within these tissues could then lead to improved outcomes when utilizing immunotherapy for treatment of this disease. Importantly, various cell types, interactions, and cellular neighborhoods were associated with five-year survival status. Of note, increases in cellular interactions between T lymphocytes, positive for programmed cell death protein 1, and myeloid-derived suppressor cells were observed in the 5-year deceased cohort. Additionally, cellular neighborhood analysis identified an Immune-Cold Parenchyma cellular neighborhood, also associated with worse 5-year survival. Finally, the Osteosarcoma Spatial Score, which approximates effector immune activity in the immune tumor microenvironment through the spatial proximity of immune and tumor cells, was increased within 5-year survivors, suggesting improved effector signaling in this patient cohort. Ultimately, these data represent a robust spatial multiplexed immunofluorescence analysis of the metastatic osteosarcoma immune tumor microenvironment. Various communication networks, and their association with survival, were described. In the future, identification of these networks may suggest the use of specific, combinatory immunotherapeutic strategies for improved anti-tumor immune responses and outcomes in osteosarcoma. [ABSTRACT FROM AUTHOR]

Introduction: Colorectal cancer (CRC) is the world's third most frequent cancer, with a significant mortality rate due to late detection. There is a need to search for biomarkers that can detect colorectal cancer at an early stage. MicroRNAs (miRNAs) regulate several targets that function as oncogenes and/or tumor suppressor genes, so any change in microRNA expression level can predict abnormality. Objective: The objective of the study was to evaluate the expression of miR-1290, and Suppressor of cancer cell invasion (SCAI) gene that may be used as biomarkers for early diagnosis of colorectal carcinoma. Methodology: This study included 50 subjects consisting of newly diagnosed colorectal carcinoma patients (n = 25), and healthy controls (n = 25). After RNA isolation and reverse transcription, the expression level of miR-1290 and SCAI gene in the tissues and plasma samples of CRC patients were analyzed using real time PCR and compared with healthy individuals as normal controls. The 2−ΔΔCt formula was used to compute the fold-change, while using miR-16 and GAPDH as reference genes for normalization. Results: We found that miR-1290 is upregulated, whereas SCAI gene is downregulated in both plasma and tissue samples of CRC patients. For miR-1290, the sensitivity was 96% and specificity was 100%, and for SCAI, 100% sensitivity and 88% specificity was calculated by ROC analysis. Conclusion: The expression of miR-1290 and SCAI gene may be utilized as biomarkers for diagnosis of colorectal carcinoma. [ABSTRACT FROM AUTHOR]

Introduction: Spinal cord injury (SCI) leads to severe disabilities and remains a significant social and economic challenge. Despite advances in medical research, there are still no effective treatments for SCI. Human amnion-derived mesenchymal stem cells (hAMSCs) have shown potential due to their antiinflammatory and neuroprotective effects. This study evaluates the therapeutic potential of intravenously administered hAMSCs in SCI models. Methods: Three days after induction of SCI with forceps calibrated with a 0.2mm gap, hAMSCs or vehicle were administered intravenously. Up to 4 weeks of SCI induction, motor function was assessed by scores on the Basso Mouse Locomotor Scale (BMS) and the Basso-Beattie-Bresnahan Scale (BBB), and sensory function by hindlimb withdrawal reflex using von Frey filaments. Six weeks after SCI induction, gait function was assessed using three-dimensional motion analysis. Immunohistochemistry, polymerase chain reaction (PCR), flow cytometry, and ELISA assay were performed to clarify the mechanisms of functional improvement. Results: The hAMSC treatment significantly improved sensory response and gait function. In the SCI site, immunohistochemistry showed a reduction in Iba1-positive cells and PCR revealed decreased TNFa and increased BDNF levels in the hAMSC-treated group. In assessing the systemic inflammatory response, hAMSC treatment reduced monocytic bone marrow-derived suppressor cells (MMDSCs) and Ly6C-positive inflammatory macrophages in the bone marrow by flow cytometry and serum NO levels by ELISA assay. Discussion: This study demonstrates the therapeutic potential of the hAMSC in SCI, with improvements in gait and sensory functions and reduced inflammation both locally and systemically. The findings support further investigation of the hAMSC as a potential treatment for SCI, focusing on their ability to modulate inflammation and promote neuroprotection. [ABSTRACT FROM AUTHOR]

T-cell acute lymphoblastic leukemia is an aggressive neoplasia due to hyper-proliferation of lymphoid progenitors and lacking a definitive cure to date. Notch-activating mutations are the most common in driving disease onset and progression, often in combination with sustained activity of NF-κB. Myeloid-derived suppressor cells represent a mixed population of immature progenitors exerting suppression of anti-cancer immune responses in the tumor microenvironment of many malignancies. We recently reported that in a transgenic murine model of Notch3-dependent T-cell acute lymphoblastic leukemia there is an accumulation of myeloid-derived suppressor cells, dependent on both Notch signaling deregulation and IL-6 production inside tumor T-cells. However, possible interaction between NF-κB and Notch in this context remains unexplored. Interestingly, we also reported that Notch3 transgenic and NF-κB1/p50 deleted double mutant mice display massive myeloproliferation. Here, we demonstrated that the absence of the p50 subunit in these mice dramatically enhances the induction and suppressive function of myeloid-derived suppressor cells. This runs in parallel with an impressive increase in IL-6 concentration in the peripheral blood serum, depending on IL-6 hyper-production by tumor T-cells from double mutant mice. Mechanistically, IL-6 increase relies on loss of the negative control exerted by the p50 subunit on the IL-6 promoter. Our results reveal the Notch/NF-κB cross-talk in regulating myeloid-derived suppressor cell biology in T-cell leukemia, highlighting the need to consider carefully the pleiotropic effects of NF-κB-based therapy on the tumor microenvironment. [ABSTRACT FROM AUTHOR]

A disbalance between immune regulatory cells and inflammatory cells is known to drive atherosclerosis. However, the exact mechanism is not clear. Here, we investigated the homing of immune regulatory cells, mainly, regulatory T cells (Tregs) and myeloid‐derived suppressor cells (MDSCs) subsets in asymptomatic coronary artery disease (CAD) risk factor‐exposed young individuals (dyslipidemia [DLP] group) and stable CAD patients (CAD group). Compared with healthy controls (HCs), Tregs frequency was reduced in both DLP and CAD groups but expressed high levels of CCR5 in both groups. The frequency of monocytic‐myeloid‐derived suppressor cells (M‐MDSCs) was increased while polymorphonuclear myeloid‐derived suppressor cells (PMN‐MDSCs) were decreased in CAD patients only. Interestingly, although unchanged in frequency, M‐MDSCs of the DLP group expressed high levels of CCR5. Serum levels of chemokines (CCL5, CX3CL1, CCL26) and inflammatory cytokines (IL‐6, IL‐1β, IFN‐γ, TNF‐α) were higher in the DLP group. Stimulation with inflammatory cytokines augmented CCR5 expression in Tregs and M‐MDSCs isolated from HCs. Activated endothelial cells showed elevated levels of CX3CL1 and CCL5 in vitro. Blocking CCR5 with D‐Ala‐peptide T‐amide (DAPTA) increased Treg and M‐MDSC frequency in C57Bl6 mice fed a high‐fat diet. In accelerated atherosclerosis model, DAPTA treatment led to the formation of smooth muscle‐rich plaque with less macrophages. Thus, we show that CCR5‐CCL5 axis is instrumental in recruiting Tregs and M‐MDSCs to dysfunctional endothelium in the asymptomatic phase of atherosclerosis contributing to atherosclerosis progression. Drugs targeting CCR5 in asymptomatic and CAD risk‐factor/s‐exposed individuals might be a novel therapeutic regime to diminish atherogenesis. [ABSTRACT FROM AUTHOR]

Chimeric antigen receptor T (CAR-T) cell therapy has greatly improved the prognosis of relapsed and refractory patients with large B-cell lymphoma (LBCL). Early identification and intervention of patients who may respond poorly to CAR-T cell therapy will help to improve the efficacy. Ninety patients from a Chinese cohort who received CAR-T cell therapy and underwent 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) scans at the screening stage (median time to infusion 53.5 days, range 27–176 days), 1 month and 3 months after CAR-T cell infusion were analyzed, with RNA-sequencing conducted on 47 patients at the screening stage. Patients with maximum diameter of the largest lesion (Dmax) < 6 cm (N = 60) at screening stage showed significantly higher 3-month complete response rate (85.0% vs. 33.3%, P < 0.001), progression-free survival (HR 0.17; 95% CI 0.08–0.35, P < 0.001) and overall survival (HR 0.18; 95% CI 0.08–0.40, P < 0.001) than those with Dmax ≥ 6 cm (N = 30). Besides, at the screening stage, Dmax combined with extranodal involvement was more efficient in distinguishing patient outcomes. The best cut-off values for total metabolic tumor volume (tMTV) and total lesion glycolysis (tTLG) at the screening stage were 50cm3 and 500 g, respectively. A prediction model combining maximum standardized uptake value (SUVmax) at 1 month after CAR-T cell therapy (M1) and tTLG clearance rate was established to predict early progression for partial response/stable disease patients evaluated at M1 after CAR-T cell therapy and validated in Lyon cohort. Relevant association of the distance separating the two farthest lesions, standardized by body surface area to the severity of neurotoxicity (AUC = 0.74; P = 0.034; 95% CI, 0.578–0.899) after CAR-T cell therapy was found in patients received axicabtagene ciloleucel. In patients with Dmax ≥ 6 cm, RNA-sequencing analysis conducted at the screening stage showed enrichment of immunosuppressive-related biological processes, as well as increased M2 macrophages, cancer-associated fibroblasts, myeloid-derived suppressor cells, and intermediate exhausted T cells. Collectively, immunosuppressive tumor microenvironment may serve as a negative prognostic indicator in patients with high tumor burden who respond poorly to CAR-T cell therapy. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusion Osteoporosis is a severe bone disease with a complex pathogenesis involving various immune processes. With the in‐depth understanding of bone immune mechanisms, discovering new therapeutic targets is crucial for the prevention and treatment of osteoporosis. This study aims to explore novel bone immune markers related to osteoporosis based on single‐cell and transcriptome data, utilizing bioinformatics and machine learning methods, in order to provide novel strategies for the diagnosis and treatment of the disease.Single cell and transcriptome data sets were acquired from Gene Expression Omnibus (GEO). The data was then subjected to cell communication analysis, pseudotime analysis, and high dimensional WGCNA (hdWGCNA) analysis to identify key immune cell subpopulations and module genes. Subsequently, ConsensusClusterPlus analysis was performed on the key module genes to identify different diseased subgroups in the osteoporosis (OP) training set samples. The immune characteristics between subgroups were evaluated using Cibersort, EPIC, and MCP counter algorithms. OP's hub genes were screened using 10 machine learning algorithms and 113 algorithm combinations. The relationship between hub genes and immunity and pathways was established by evaluating the immune and pathway scores of the training set samples through the ESTIMATE, MCP‐counter, and ssGSEA algorithms. Real‐time fluorescence quantitative PCR (RT‐qPCR) testing was conducted on serum samples collected from osteoporosis patients and healthy adults.In OP samples, the proportions of bone marrow‐derived mesenchymal stem cells (BM‐MSCs) and neutrophils increased significantly by 6.73% (from 24.01% to 30.74%) and 6.36% (from 26.82% to 33.18%), respectively. We found 16 intersection genes and four hub genes (DND1, HIRA, SH3GLB2, and F7). RT‐qPCR results showed reduced expression levels of DND1, HIRA, and SH3GLB2 in clinical blood samples of OP patients. Moreover, the four hub genes showed positive correlations with neutrophils (0.65–0.90), immature B cells (0.76–0.92), and endothelial cells (0.79–0.87), while showing negative correlations with myeloid‐derived suppressor cells (negative 0.54–0.73), T follicular helper cells (negative 0.71–0.86), and natural killer T cells (negative 0.75–0.85).Neutrophils play a crucial role in the occurrence and development of osteoporosis. The four hub genes potentially inhibit metabolic activities and trigger inflammation by interacting with other immune cells, thereby significantly contributing to the onset and diagnosis of OP. [ABSTRACT FROM AUTHOR]

Aim Materials and methods Results Conclusion Although immune checkpoint inhibitors (ICPi) for salivary gland cancer (SGC) have been investigated in clinical trials, details of the tumor immune microenvironment (TIME) remain unclear. This research aimed to elucidate the TIME of SGC and its relationship with tumor mutation burden (TMB) and to explore the rationale for the applicability of ICPi.We selected five pathological types, namely adenoid cystic carcinoma (ACC); adenocarcinoma, not otherwise specified (ANOS); salivary duct carcinoma (SDC); and low/high‐grade mucoepidermoid carcinoma (MEClow/high). We investigated the TIME and TMB of each pathological type. TIME was evaluated by multiplexed fluorescent immunohistochemistry. TMB was measured by next‐generation sequencing.ACC and MEChigh showed the lowest and highest infiltration of immune effector and suppressor cells in both tumor and stroma. ANOS, SDC, and MEClow showed modest infiltration of immune effector cells in tumors. Correlation analysis showed a positive correlation between CD3+CD8+ T cells in tumor and TMB (r = 0.647). CD3+CD8+ T cells in tumors showed a positive correlation with programmed cell death‐ligand 1 expression in tumor cells (r = 0.513) and a weak positive correlation with CD3+CD4+Foxp3+ cells in tumors (r = 0.399). However, no correlation was observed between CD3+CD8+ T cells and CD204+ cells in tumors (r = ‐0.049).The TIME of ACC was the so‐called immune desert type, which may explain the mechanisms of the poor response to ICPi in previous clinical trials. On the other hand, MEChigh was the immune‐inflamed type, and this may support the rationale of ICPi for this pathological subtype. [ABSTRACT FROM AUTHOR]

Tumor cells possess complex immune evasion mechanisms to evade immune system attacks, primarily through metabolic reprogramming, which significantly alters the tumor microenvironment (TME) to modulate immune cell functions. When a tumor is sufficiently immunogenic, it can activate cytotoxic T-cells to target and destroy it. However, tumors adapt by manipulating their metabolic pathways, particularly glucose, amino acid, and lipid metabolism, to create an immunosuppressive TME that promotes immune escape. These metabolic alterations impact the function and differentiation of non-tumor cells within the TME, such as inhibiting effector T-cell activity while expanding regulatory T-cells and myeloid-derived suppressor cells. Additionally, these changes lead to an imbalance in cytokine and chemokine secretion, further enhancing the immunosuppressive landscape. Emerging research is increasingly focusing on the regulatory roles of non-tumor cells within the TME, evaluating how their reprogrammed glucose, amino acid, and lipid metabolism influence their functional changes and ultimately aid in tumor immune evasion. Despite our incomplete understanding of the intricate metabolic interactions between tumor and non-tumor cells, the connection between these elements presents significant challenges for cancer immunotherapy. This review highlights the impact of altered glucose, amino acid, and lipid metabolism in the TME on the metabolism and function of non-tumor cells, providing new insights that could facilitate the development of novel cancer immunotherapies. [ABSTRACT FROM AUTHOR]

The article discusses the presence of myeloid-derived suppressor cells (MDSCs) in patients with clonal cytopenia of undetermined significance (CCUS) and low-risk myelodysplastic syndrome (LR-MDS). The study found that MDSCs were activated in the bone marrow of these patients, along with an increased proportion of CTLA-4+ T cells and alterations in T-cell memory subsets in peripheral blood. These immune changes suggest an early inflammatory state in CCUS/LR-MDS patients, highlighting the potential role of MDSCs in disease progression. Further research is needed to explore the relationship between immune dysregulation and molecular characteristics in these patients. [Extracted from the article]

Tumour cell senescence can be induced by various factors, including DNA damage, inflammatory signals, genetic toxins, ionising radiation and nutrient metabolism. The senescence‐associated secretory phenotype (SASP), secreted by senescent tumour cells, possesses the capacity to modulate various immune cells, including macrophages, T cells, natural killer cells and myeloid‐derived suppressor cells, as well as vascular endothelial cells and fibroblasts within the tumour microenvironment (TME), and this modulation can result in either the promotion or suppression of tumorigenesis and progression. Exploring the impact of SASP on the TME could identify potential therapeutic targets, yet limited studies have dissected its functions. In this review, we delve into the causes and mechanisms of tumour cell senescence. We then concentrate on the influence of SASP on the tumour immune microenvironment, angiogenesis, extracellular matrix and the reprogramming of cancer stem cells, along with their associated tumour outcomes. Last, we present a comprehensive overview of the diverse array of senotherapeutics, highlighting their prospective advantages and challenge for the treatment of cancer patients. Key points: Senescence‐associated secretory phenotype (SASP) secretion from senescent tumour cells significantly impacts cancer progression and biology.SASP is involved in regulating the remodelling of the tumour microenvironment, including immune microenvironment, vascular, extracellular matrix and cancer stem cells.Senotherapeutics, such as senolytic, senomorphic, nanotherapy and senolytic vaccines, hold promise for enhancing cancer treatment efficacy. [ABSTRACT FROM AUTHOR]

Background: Myeloid‐derived suppressor cells (MDSCs) play a pivotal role in immunosuppression and tumor progression in hepatocellular carcinoma (HCC). While various treatments like surgical resection, ablation, and radiotherapy have been studied for their effects on circulating MDSC frequencies in HCC patients, the findings remain inconclusive. Transarterial Chemoembolization (TACE) stands as the standard care for unresectable HCC, with Microparticle TACE (mTACE) gaining prominence for its capacity to induce significant tumor necrosis. However, the immunological ramifications of such pathological outcomes are scarcely reported. Methods and Results: This study aims to elucidate the alterations in MDSC subtypes, specifically monocytic MDSCs (mMDSCs) and early‐stage MDSCs (eMDSCs), post‐mTACE and to investigate their clinical correlations in HCC patients. A cohort comprising 75 HCC patients, 16 liver cirrhosis patients, and 20 healthy controls (HC) was studied. Peripheral blood samples were collected and analyzed for MDSC subtypes. The study also explored the associations between MDSC frequencies and various clinical parameters in HCC patients. The frequency of mMDSCs was significantly elevated in the HCC group compared to liver cirrhosis and HC. Importantly, mMDSC levels were strongly correlated with aggressive clinical features of HCC, including tumor size, vascular invasion, and distant metastasis. Post‐mTACE, a marked reduction in mMDSC frequencies was observed, while eMDSC levels remained stable. Conclusions: Our findings underscore the critical role of mMDSCs in HCC pathogenesis and their potential as a therapeutic target. The study also highlights the efficacy of mTACE in modulating the immunosuppressive tumor microenvironment, thereby opening new avenues for combinatorial immunotherapeutic strategies in HCC management. Highlights: The study underscores the pivotal role of myeloid‐derived suppressor cells (MDSCs) in driving immunosuppression and tumor progression in hepatocellular carcinoma (HCC).It highlights the inconclusive findings regarding the effects of various HCC treatments on MDSC frequencies, including surgical resection, ablation, and radiotherapy.The study delves into the immunological consequences of Microparticle Transarterial Chemoembolization (mTACE), a treatment gaining prominence for inducing significant tumor necrosis in unresectable HCC.It investigates the clinical correlations between MDSC frequencies, specifically monocytic MDSCs (mMDSCs), and aggressive HCC features like tumor size, vascular invasion, and distant metastasis.The research highlights the therapeutic potential of targeting mMDSCs and demonstrates the effectiveness of mTACE in reshaping the immunosuppressive tumor microenvironment. This offers new avenues for innovative immunotherapeutic approaches in HCC management. [ABSTRACT FROM AUTHOR]

The fatty acid receptor CD36 is expressed on various malignant cells and is suggested to contribute to tumor progression. CD36 is also expressed by several immune cells and involved in immune responses and may be a potential target in cancer immunotherapy. In this study, we investigated whether the selective inhibition of CD36 can inhibit tumor progression and facilitate an antitumor immune response in oral squamous carcinoma cells (OSCCs). We assessed the effects of sulfosuccinimidyl oleate sodium (SSO), a CD36 inhibitor, on the proliferation apoptosis and alteration in tumor cell surface expression levels of immune accessory molecules in vitro. We also assessed whether SSO-treated OSCCs could promote a T cell response via a Mixed Lymphocyte Reaction (MLR) assay. We also investigated the direct antitumor effects and immunomodulatory effects of SSO using a mouse oral cancer OSCC model. SSO treatment significantly inhibited OSCC proliferation, increased apoptotic cell death, and upregulated the cell surface expression of several immune accessory molecules, including CD83, MHC-Class II, and PD-L1. SSO-treated OSCCs augmented T cell proliferation following MLR. In vivo SSO administration significantly attenuated mouse tumor growth with an increased proportion of immune cells, including CD4+ T, CD8+ T, and dendritic cells; it also decreased the proportion of immune suppressive cells, such as myeloid-derived suppressor and regulatory T cells. These results suggest that the selective inhibition of CD36 can induce direct and indirect antitumor effects by facilitating host antitumor immune responses in OSCCs. [ABSTRACT FROM AUTHOR]

Circulating tumor cell (CTC) clusters represent formidable precursors of cancer metastasis due to their heightened immune resistance against natural killer (NK) cells. Despite this, the cytotoxicity of NK cells against CTC clusters, particularly their interaction with other immune cells such as neutrophils, remains inadequately examined. This study introduces a dual‐nozzle integrated droplet microfluidic chip (dual‐nozzle chip) designed to facilitate the deterministic encapsulation of three distinct cell types—CTCs, NK cells, and neutrophils—to monitor the dynamic cytotoxicity between immune cells and target cells. The dual‐nozzle chip comprises double‐spiral channels and a serpentine channel for inertial cell focusing, alongside dual‐nozzle oil phases employed to generate monodisperse droplets at high flow rates. Utilizing Rayleigh–Plateau instability, the focused cell streams, characterized by high inertia, undergo pinching off into monodisperse droplets at the flow‐focusing junction, where dual‐nozzle oil phases are introduced. Consequently, triple cells are paired at the desired ratios, overcoming the intrinsic challenge posed by the Poisson distribution. A droplet‐based assay demonstrates that NK cell‐mediated cytotoxicity varies depending on the type of cancer cells and the presence of suppressor cells. The design strategy of the dual‐nozzle chip exhibits promises for broader applications, emphasizing its potential for analyzing diverse cell‐to‐cell interactions. [ABSTRACT FROM AUTHOR]

An aged immune system undergoes substantial changes where myelopoiesis dominates within the bone marrow. Monocytic‐MDSCs (M‐MDSCs) have been found to play an important role in osteoclastogenesis and bone resorption. In this study, we sought to provide a more comprehensive understanding of the osteoclastogenic potential of bone marrow M‐MDSCs during normal aging through transcriptomic and metabolic changes. Using young mature and aged mice, detailed immunophenotypic analyses of myeloid cells revealed that the M‐MDSCs were not increased in bone marrow, however M‐MDSCS were significantly expanded in peripheral tissues. Although aged mice exhibited a similar number of M‐MDSCs in bone marrow, these M‐MDSCs had significantly higher osteoclastogenic potential and greater demineralization activity. Intriguingly, osteoclast progenitors from aged bone marrow M‐MDSCs exhibited greater mitochondrial respiration rate and glucose metabolism. Further, transcriptomic analyses revealed the upregulation of mitochondrial oxidative phosphorylation and glucose metabolism genes. Interestingly, there was 8‐fold increase in Cd38 mRNA gene expression, consistent with the Mouse Aging Cell Atlas transcriptomic database, and confirmed by qRT‐PCR. CD38 regulates NAD+ availability, and 78c, a small molecule inhibitor of CD38, reduced the mitochondrial oxygen consumption rate and glucose metabolism and inhibited the osteoclastogenic potential of aged mice bone marrow‐derived M‐MDSCs. These results indicate that the age‐related increase in Cd38 expression in M‐MDSCs bias the transcriptome of M‐MDSCs towards osteoclastogenesis. This enhanced understanding of the mechanistic underpinnings of M‐MDSCs and their osteoclastogenesis during aging could lead to new therapeutic approaches for age‐related bone loss and promote healthy aging. [ABSTRACT FROM AUTHOR]

Conventional CD4pos regulatory T (Treg) cells characterized by expression of the key transcription factor forkhead box P3 (FoxP3) are crucial to control immune responses, thereby maintaining homeostasis and self-tolerance. Within the substantial population of non-conventional T cell receptor (TCR)αβpos CD4negCD8αneg double-negative (dn) T cells of dogs, a novel FoxP3pos Treglike subset was described that, similar to conventional CD4pos Treg cells, is characterized by high expression of CD25. Noteworthy, human and murine TCRαβpos regulatory dn T cells lack FoxP3. Immunosuppressive capacity of canine dn T cells was hypothesized based on expression of inhibitory molecules (interleukin (IL)-10, cytotoxic T-lymphocyte associated protein 4, CTLA4). Here, to verify their regulatory function, the dnCD25pos (enriched for FoxP3pos Treg-like cells) and the dnCD25neg fraction, were isolated by fluorescence-activated cell sorting from peripheral blood mononuclear cells (PBMC) of Beagle dogs and analyzed in an in vitro suppression assay in comparison to conventional CD4posCD25pos Treg cells (positive control) and CD4posCD25neg T cells (negative control). Canine dnCD25pos T cells suppressed the Concanavalin A-driven proliferation of responder PBMC to a similar extent as conventional CD4posCD25pos Treg cells. Albeit to a lesser extent than FoxP3-enriched dn and CD4posCD25pos populations, even dnCD25neg T cells reduced the proliferation of responder cells. This is remarkable, as dnCD25neg T cells have a FoxP3neg phenotype comparable to non-suppressive CD4posCD25neg T cells. Both, CD25pos and CD25neg dn T cells, can mediate suppression independent of cell-cell contact and do not require additional signals from CD4posCD25neg T cells to secrete inhibitory factors in contrast to CD4posCD25pos T cells. Neutralization of IL-10 completely abrogated the suppression by dnCD25pos and CD4posCD25pos Treg cells in a Transwell™ system, while it only partially reduced suppression by dnCD25neg T cells. Taken together, unique canine nonconventional dnCD25pos FoxP3pos Treg-like cells are potent suppressor cells in vitro. Moreover, inhibition of proliferation of responder T cells by the dnCD25neg fraction indicates suppressive function of a subset of dn T cells even in the absence of FoxP3. The identification of unique immunoregulatory nonconventional dn T cell subpopulations of the dog in vitro is of high relevance, given the immunotherapeutic potential of manipulating regulatory T cell responses in vivo. [ABSTRACT FROM AUTHOR]

The combination of cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) with endocrine therapy (ET) is the standard-of-care for estrogen receptor (ER)-positive, HER2-negative (ER+/HER2− advanced/metastatic breast cancer (mBC). However, the impact of CDK4/6i on circulating immune cells and circulating tumor cells (CTCs) in patients receiving CDK4/6i and ET (CDK4/6i+ET) remains poorly understood. This was a prospective cohort study including 44 patients with ER+/HER2− mBC treated with CDK4/6i+ET in either first or second line. Peripheral blood samples were collected before (baseline) and 3 months (t2) after therapy. Immune cell's subsets were quantified by flow cytometry, and microfluidic-captured CTCs were counted and classified according to the expression of cytokeratin and/or vimentin. Patients were categorized according to response as responders (progression-free survival [PFS] ≥ 6.0 months; 79.1%) and non-responders (PFS < 6.0 months; 20.9%). CDK4/6i+ET resulted in significant changes in the hematological parameters, including decreased hemoglobin levels and increased mean corpuscular volume, as well as reductions in neutrophil, eosinophil, and basophil counts. Specific immune cell subsets, such as early-stage myeloid-derived suppressor cells, central memory CD4+ T cells, and Vδ2+ T cells expressing NKG2D, decreased 3 months after CDK4/6i+ET. Additionally, correlations between the presence of CTCs and immune cell populations were observed, highlighting the interplay between immune dysfunction and tumor dissemination. This study provides insights into the immunomodulatory effects of CDK4/6i+ET, underscoring the importance of considering immune dynamics in the management of ER+/HER2− mBC. [ABSTRACT FROM AUTHOR]

A comprehensive immune landscape for Brucella infection is crucial for developing new treatments for brucellosis. Here, we utilized single‐cell RNA sequencing (scRNA‐seq) of 290,369 cells from 35 individuals, including 29 brucellosis patients from acute (n = 10), sub‐acute (n = 9), and chronic (n = 10) phases as well as six healthy donors. Enzyme‐linked immunosorbent assays were applied for validation within this cohort. Brucella infection caused a significant change in the composition of peripheral immune cells and inflammation was a key feature of brucellosis. Acute patients are characterized by potential cytokine storms resulting from systemic upregulation of S100A8/A9, primarily due to classical monocytes. Cytokine storm may be mediated by activating S100A8/A9‐TLR4‐MyD88 signaling pathway. Moreover, monocytic myeloid‐derived suppressor cells were the probable contributors to immune paralysis in acute patients. Chronic patients are characterized by a dysregulated Th1 response, marked by reduced expression of IFN‐γ and Th1 signatures as well as a high exhausted state. Additionally, Brucella infection can suppress apoptosis in myeloid cells (e.g., mDCs, classical monocytes), inhibit antigen presentation in professional antigen‐presenting cells (APCs; e.g., mDC) and nonprofessional APCs (e.g., monocytes), and induce exhaustion in CD8+ T/NK cells, potentially resulting in the establishment of chronic infection. Overall, our study systemically deciphered the coordinated immune responses of Brucella at different phases of the infection, which facilitated a full understanding of the immunopathogenesis of brucellosis and may aid the development of new effective therapeutic strategies, especially for those with chronic infection. Highlights: scRNA‐seq analysis reveals distinct immune responses across the acute, sub‐acute, and chronic phases of Brucella infection.Acute infection is characterized by a cytokine storm, potentially mediated by the activation of the S100A8/A9‐TLR4‐MyD88 pathway, along with immune suppression driven by Mono‐MDSCsChronic infection is marked by a dysregulated Th1 immune response and widespread exhaustion of T and NK cells. [ABSTRACT FROM AUTHOR]

Viruses are obligate intracellular pathogens as their replication depends on the metabolism of the host cell. The induction of cellular suicide, known as programmed cell death (PCD), has the potential to hinder viral replication and act as a first line of defense against viral pathogens. Apoptosis, necroptosis, and pyroptosis are three important PCD modalities. Different signaling pathways are involved in their execution, and they also differ in their ability to cause inflammation. Cytomegaloviruses (CMV), beta-herpesviruses with large double-stranded DNA genomes, encode a great variety of immune evasion genes, including several cell death suppressors. While CMV inhibitors of apoptosis and necroptosis have been known and studied for years, the first pyroptosis inhibitor has been identified and characterized only recently. Here, we describe how human and murine CMV interfere with apoptosis, necroptosis, and pyroptosis signaling pathways. We also discuss the importance of the different PCD forms and their viral inhibitors for the containment of viral replication and spread in vivo. [ABSTRACT FROM AUTHOR]

Innate immune cells in the colorectal cancer microenvironment mainly include macrophages, neutrophils, natural killer cells, dendritic cells and bone marrowderived suppressor cells. They play a pivotal role in tumor initiation and progression through the secretion of diverse cytokines, chemokines, and other factors that govern these processes. Colorectal cancer is a common malignancy of the gastrointestinal tract, and understanding the role of innate immune cells in the microenvironment of CRC may help to improve therapeutic approaches to CRC and increase the good prognosis. In this review, we comprehensively explore the pivotal role of innate immune cells in the initiation and progression of colorectal cancer (CRC), alongside an extensive evaluation of the current landscape of innate immune cell-based immunotherapies, thereby offering valuable insights for future research strategies and clinical trials. [ABSTRACT FROM AUTHOR]

Tumor‐associated chronic inflammation severely restricts the efficacy of immunotherapy in cold tumors. Here, a programmable release hydrogel‐based engineering scaffold with multi‐stimulation and reactive oxygen species (ROS)‐response (PHOENIX) is demonstrated to break the chronic inflammatory balance in cold tumors to induce potent immunity. PHOENIX can undergo programmable release of resiquimod and anti‐OX40 under ROS. Resiquimod is first released, leading to antigen‐presenting cell maturation and the transformation of myeloid‐derived suppressor cells and M2 macrophages into an antitumor immune phenotype. Subsequently, anti‐OX40 is transported into the tumor microenvironment, leading to effector T‐cell activation and inhibition of Treg function. PHOENIX consequently breaks the chronic inflammation in the tumor microenvironment and leads to a potent immune response. In mice bearing subcutaneous triple‐negative breast cancer and metastasis models, PHOENIX effectively inhibited 80% and 60% of tumor growth, respectively. Moreover, PHOENIX protected 100% of the mice against TNBC tumor rechallenge by electing a robust long‐term antigen‐specific immune response. An excellent inhibition and prolonged survival in PHOENIX‐treated mice with colorectal cancer and melanoma is also observed. This work presents a potent therapeutic scaffold to improve immunotherapy efficiency, representing a generalizable and facile regimen for cold tumors. [ABSTRACT FROM AUTHOR]

Immune exhaustion corresponds to a loss of effector function of T cells that associates with cancer or chronic infection. Here, our objective was to decipher the mechanisms involved in the immune suppression of myeloid-derived suppressor cells (MDSCs) and to explore the potential to target these cells for immunotherapy to enhance checkpoint blockade efficacy in a chronic parasite infection. We demonstrated that programmed cell-death-1 (PD-1) expression was significantly upregulated and associated with T-cell dysfunction in advanced alveolar echinococcosis (AE) patients and in Echinococcus multilocularis-infected mice. PD-1 blockade ex vivo failed to reverse AE patients' peripheral blood T-cell dysfunction. PD-1/PD-L1 blockade or PD-1 deficiency had no significant effects on metacestode in mouse model. This was due to the inhibitory capacities of immunosuppressive granulocytic MDSCs (G-MDSCs), especially in the liver surrounding the parasite pseudotumor. MDSCs suppressed T-cell function in vitro in an indoleamine 2, 3 dioxygenase 1 (IDO1)-dependent manner. Although depleting MDSCs alone restored T-cell effector functions and led to some limitation of disease progression in E. multilocularis-infected mice, combination with PD-1 blockade was better to induce antiparasitic efficacy. Our findings provide preclinical evidence in support of targeting MDSC or combining such an approach with checkpoint blockade in patients with advanced AE. (200 words) Myeloid-derived suppressor cells play an important role in immune suppression caused by Echinococcus multilocularis infection. This study demonstrates that the removal of this cell type effectively restores T-cell function and potentiates PD-1 blockade therapy in chronic liver infection. [ABSTRACT FROM AUTHOR]

Objective: Immunotherapy, specifically immune checkpoint inhibitors (ICIs), has revolutionized cancer treatment. However, it can also cause immune‐related adverse events (irAEs). This study aimed to develop a clinically practical animal model of irAEs using BALB/c mice. Methods: Subcutaneous tumors of mouse breast cancer 4T1 cells were generated in inbred BALB/c mice. The mice were treated with programmed death‐1 (PD‐1) and cytotoxic t‐lymphocyte antigen 4 (CTLA‐4) inhibitors once every 3 days for five consecutive administration cycles. Changes in tumor volume and body weight were recorded. Lung computed tomography (CT) scans were conducted. The liver, lungs, heart, and colon tissues of the mice were stained with hematoxylin–eosin (H&E) staining to observe inflammatory infiltration and were scored. Serum samples were collected, and enzyme‐linked immunosorbent assay (ELISA) was used to detect the levels of ferritin, glutamic‐pyruvic transaminase (ALT), tumor necrosis factor‐α (TNF‐α), interferon‐gamma (IFN‐γ), and interleukin‐6 (IL‐6). Mouse liver and lung cell suspensions were prepared, and changes in macrophages, T cells, myeloid‐derived suppressor cells (MDSCs), and regulatory (Treg) cells were detected by flow cytometry. Results: Mice treated with PD‐1 and CTLA‐4 inhibitors showed significant reductions in tumor volume and body weight. The tissue inflammatory scores in the experimental group were significantly higher than those in the control group. Lung CT scans of mice in the experimental group showed obvious inflammatory spots. Serum levels of ferritin, IL‐6, TNF‐α, IFN‐γ, and ALT were significantly elevated in the experimental group. Flow cytometry analysis revealed a substantial increase in CD3+T cells, Treg cells, and macrophages in the liver and lung tissues of mice in the experimental group compared with the control group, and the change trend of MDSCs was opposite. Conclusions: The irAE‐related animal model was successfully established in BALB/c mice using a combination of PD‐1 and CTLA‐4 inhibitors through multiple administrations with clinical translational value and practical. This model offers valuable insights into irAE mechanisms for further investigation. [ABSTRACT FROM AUTHOR]

Background: Paracoccidioidomycosis (PCM) is a systemic endemic fungal disease prevalent in Latin America. Previous studies revealed that host immunity against PCM is tightly regulated by several suppressive mechanisms mediated by tolerogenic plasmacytoid dendritic cells, the enzyme 2,3 indoleamine dioxygenase (IDO-1), regulatory T-cells (Tregs), and through the recruitment and activation of myeloid-derived suppressor cells (MDSCs). We have recently shown that Dectin-1, TLR2, and TLR4 signaling influence the IDO-1-mediated suppression caused by MDSCs. However, the contribution of these receptors in the production of important immunosuppressive molecules used by MDSCs has not yet been explored in pulmonary PCM. Methods: We evaluated the expression of PD-L1, IL-10, as well as nitrotyrosine by MDSCs after anti-Dectin-1, anti-TLR2, and anti-TLR4 antibody treatment followed by P. brasiliensis yeasts challenge in vitro. We also investigated the influence of PD-L1, IL-10, and nitrotyrosine in the suppressive activity of lung-infiltrating MDSCs of C57BL/6-WT, Dectin-1KO, TLR2KO, and TLR4KO mice after in vivo fungal infection. The suppressive activity of MDSCs was evaluated in cocultures of isolated MDSCs with activated T-cells. Results: A reduced expression of IL-10 and nitrotyrosine was observed after in vitro anti-Dectin-1 treatment of MDSCs challenged with fungal cells. This finding was further confirmed in vitro and in vivo by using Dectin-1KO mice. Furthermore, MDSCs derived from Dectin-1KO mice showed a significantly reduced immunosuppressive activity on the proliferation of CD4+ and CD8+ T lymphocytes. Blocking of TLR2 and TLR4 by mAbs and using MDSCs from TLR2KO and TLR4KO mice also reduced the production of suppressive molecules induced by fungal challenge. In vitro, MDSCs from TLR4KO mice presented a reduced suppressive capacity over the proliferation of CD4+ T-cells. Conclusion: We showed that the pathogen recognition receptors (PRRs) Dectin-1, TLR2, and TLR4 contribute to the suppressive activity of MDSCs by inducing the expression of several immunosuppressive molecules such as PD-L1, IL-10, and nitrotyrosine. This is the first demonstration of a complex network of PRRs signaling in the induction of several suppressive molecules by MDSCs and its contribution to the immunosuppressive mechanisms that control immunity and severity of pulmonary PCM. [ABSTRACT FROM AUTHOR]

Adenosine has garnered significant attention as a potential target for overcoming tumor immune evasion. It exacerbates the immunosuppressive tumor microenvironment (TME) by incapacitating various protective immune cells. However, inhibitors targeting adenosine receptors are limited by incomplete blockade effects and off‐target toxicity, necessitating the exploration of more effective strategies. Inspired by the native biologic function of adenosine deaminase (ADA) in hydrolyzing adenosine, a bioactive catalytic nanovesicle (ENV@FeS) is designed to reverse adenosine immunosuppressive function. The nanovesicle is constructed through the serial extrusion of erythrocytes abundant with ADA, coupled with the synthesis of FeS complex in situ using Fe2+ in erythrocytes via H2S gas introduction. Notably, the bioactive nanovesicles not only promote tumor targeting and induce immunogenic cell death by the FeS‐induced photothermal effect, but also hinder the adenosine pathway by metabolizing adenosine into immunopotentiator inosine, further boosting antitumor immunity. In vivo, ENV@FeS efficiently increases the infiltration of cytotoxic T lymphocytes and M1 macrophages while reducing the production of regulatory T cells and myeloid‐derived suppressor cells, resulting in significant inhibition of tumor growth. Together, the biomimetic nanovesicle‐mediated adenosine metabolic regulation, in synergy with photothermal therapy, leads to a marked improvement in the immunogenic TME and enhances the therapeutic efficacy of photoimmunotherapy. [ABSTRACT FROM AUTHOR]

Background: In triple-negative breast cancer (TNBC) therapy, insufficient tumor infiltration by lymphocytes significantly hinders the efficacy of immune checkpoint inhibitors. We have previously demonstrated that Hainanenin-1 (HN-1), a host defense peptide (HDP) identified from Hainan frog skin, induces breast cancer apoptosis and boots anti-tumor immunity via unknown mechanism. Methods: We used in vitro experiments to observe immunogenic cell death (ICD) indicators in HN-1-treated TNBC cell lines, a mouse tumor model to verify HN-1 promotion of mice anti-tumor immune response, and an in vitro drug sensitivity test of patient-derived breast cancer cells to verify the inhibitory effect of HN-1. Results: HN-1 induced ICD in TNBC in a process during which damage-associated molecular patterns (DAMPs) were released that could further increase the anti-tumor immune response. The secretion level of interleukin 2 (IL-2), IL-12, and interferon γ in the co-culture supernatant was increased, and dendritic cells (DCs) were activated via a co-culture with HN-1-pretreated TNBC cells. As a result, HN-1 increased the infiltration of anti-tumor immune cells (DCs and T lymphocytes) in the mouse model bearing both 4T1 and EMT6 tumors. Meanwhile, regulatory T cells and myeloid-derived suppressor cells were suppressed. In addition, HN-1 induced DNA damage, and double-strand DNA release in the cytosol was significantly enhanced, indicating that HN-1 might stimulate ICD via activation of STING pathway. The knockdown of STING inhibited HN-1-induced ICD. Of note, HN-1 exhibited inhibitory effects on patient-derived breast cancer cells under three-dimensional culture conditions. Conclusions: Collectively, our study demonstrated that HN-1 could be utilized as a potential compound that might augment immunotherapy effects in patients with TNBC. [ABSTRACT FROM AUTHOR]

Autophagy is a self‐recycling machinery to maintain cellular homeostasis by degrading harmful materials in the cell. Autophagy‐related gene 5 (Atg5) is required for autophagosome maturation. However, the role of Atg5 in tumorigenesis under autophagy deficient conditions remains unclear. This study focused on the autophagy‐independent role of Atg5 and the underlying mechanism in tumorigenesis. We demonstrated that knockout of autophagy‐related genes including Atg5, Atg7, Atg9, and p62 in mouse embryonic fibroblast (MEF) cells consistently decreased cell proliferation and motility, implying that autophagy is required to maintain diverse cellular functions. An Atg7 knockout MEF (Atg7−/− MEF) cell line representing deprivation of autophagy function was used to clarify the role of Atg5 transgene in tumorigenesis. We found that Atg5‐overexpressed Atg7−/‐MEF (clone A) showed increased cell proliferation, colony formation, and migration under autophagy deficient conditions. Accordingly, rescuing the autophagy deficiency of clone A by overexpression of Atg7 gene shifts the role of Atg5 from pro‐tumor to anti‐tumor status, indicating the dual role of Atg5 in tumorigenesis. Notably, the xenograft mouse model showed that clone A of Atg5‐overexpressed Atg7−/− MEF cells induced temporal tumor formation, but could not prolong further tumor growth. Finally, biomechanical analysis disclosed increased Wnt5a secretion and p‐JNK expression along with decreased β‐catenin expression. In summary, Atg5 functions as a tumor suppressor to protect the cell under normal conditions. In contrast, Atg5 shifts to a pro‐tumor status under autophagy deprivation conditions. [ABSTRACT FROM AUTHOR]

Simple Summary: Ten-eleven-translocation (TET) 2 is implicated in human cancers such as lung, breast, skin, and kidney cancers, T-cell lymphomas, and leukemia. It is unclear whether TET2 is involved in the re-expression of the p16 tumor suppressor, which was partially silenced by CDKN2A gene methylation. The effect of DNA methyltransferase (DNMT) 1 gene status on TET2 expression following DNMT inhibitor treatment remains unknown in cancer. We found that deleting the DNMT1 gene made cancer cells prone to increased TET2 expression and re-expression of p16 after drug treatment. TET2 is involved in the demethylation of the CDKN2A gene and activation of p16 expression, and concomitant resistance to DNMT inhibitors when DNMT1 is obliterated. The long-sought data for the first time revealed a link between TET2 expression and the activation of p16 expression. The findings should have an impact on reactivating tumor suppressors and cancer treatment. Background: Ten-eleven-translocation (TET) 2 is a member of the TET family of proteins (TET1-3). DNMT1 gene deletion confers resistance to DNA methyltransferase (DNMT) inhibitors in colorectal, breast, and ovarian cancer cells. Currently, the effect of DNMT1 gene status on TET2 phenotype following DNMT inhibitor treatment is unclear in human malignancies. Methods: Human colorectal carcinoma HCT116 cells (DNMT+/+) and their isogenic DNMT1 knockout (DNMT1–/–) counterpart were treated with DNMT inhibitors. Expression of TET2 and tumor suppressor (p16ink4A and p15ink4B) proteins were examined by Western blot. Apoptosis and CDKN2A promoter demethylation following drug treatment were detected by Annexin-V apoptosis assay and methylation-specific PCR. Results: TET2 expression was robustly increased in DNMT1−/− cells by 0.5 µM and 5 µM decitabine and azacitidine treatment. Augmentation of TET2 expression was accompanied by re-expression of p16ink4A and p15ink4B proteins and CDKN2A promoter demethylation. TET2 upregulation and tumor suppressor re-expression were associated with resistance conferred by DNMT1 deletion. Treatment with 5-aza-4′-thio-2′-deoxycytidine at a low 0.5 µM dose only upregulated TET2 and reduced CDKN2A promoter methylation, and re-expression of p16ink4A in DNMT1−/− cells. DNMT inhibitors showed minimal effects on TET2 upregulation and re-expression of tumor suppressor proteins in cells with intact DNMT1. Conclusions: DNMT1 gene deletion made cancer cells prone to TET2 upregulation and activation of tumor suppressor expression upon DNMT inhibitor challenge. TET2 augmentation is concomitant with resistance to DNMT inhibitors in a DNMT1-deleted state. [ABSTRACT FROM AUTHOR]

Introduction: Myeloid-derived suppressor cell (MDSC) exhibits immunosuppressive functions and affects cancer progression, but its relationship with prostate cancer remains unclear. We elucidated the association of polymorphonuclear MDSC (PMNMDSC) and monocytic MDSC (M-MDSC) levels of the total peripheral blood mononuclear cells (PBMCs) with prostate cancer progression and evaluated their roles as prognostic indicators. Methods: We enrolled 115 patients with non-metastatic hormone-sensitive prostate cancer (nmHSPC, n = 62), metastatic hormone-sensitive prostate cancer (mHSPC, n = 23), and metastatic castration-resistant prostate cancer (mCRPC, n = 30). Subsequently, the proportions of MDSCs in each disease progression were compared. Log-rank tests and multivariate Cox regression analyses were performed to ascertain the associations of overall survival. Results: The patients with mCRPC had significantly higher PMN-MDSC percentage than those with nmHSPC and mHSPC (P = 7.73 × 10−5 and 0.0014). Significantly elevated M-MDSC levels were observed in mCRPC patients aged <70 years (P = 0.016) and with a body mass index (BMI) <25 kg/ m² (P = 0.043). The high PMN-MDSC group had notably shorter median survival duration (159 days) than the low PMN-MDSC group (768 days, log-rank P = 0.018). In the multivariate analysis including age, BMI, and MDSC subset, PMNMDSC was significantly associated with prognosis (hazard ratios, 3.48; 95% confidence interval: 1.05–11.56, P = 0.042). Discussion: PMN-MDSC levels are significantly associated with mCRPC prognosis. Additionally, we highlight the remarkable associations of age and BMI with M-MDSC levels in mCRPC, offering novel insights into MDSC dynamics in prostate cancer progression [ABSTRACT FROM AUTHOR]

The ability of tumor-derived extracellular vesicles (EVs) to modulate the function of myeloid cells is widely recognized. Hence, a comprehensive understanding of the distinct components associated with EVs and the signals that they deliver to myeloid cells could provide potential approaches to impede the immunosuppression by myeloid-derived suppressor cells (MDSCs). We investigated melanoma EV-associated microRNAs (miRs) using the RET transgenic melanoma mouse model and simulated their transfer to normal myeloid cells by transfecting immature mouse myeloid cells and human monocytes. We observed elevated levels of miR-125a-5p, -125b-5p, and let-7e-5p in mouse melanoma-infiltrating MDSCs. In addition, miR-125a-5p levels in the tumor microenvironment correlated with mouse melanoma progression. The delivery of miR-125a-5p, alone or in combination with let-7e-5p and miR-99b-5p from the same genomic cluster, to normal myeloid cells resulted in their conversion to MDSC-like cells. Our findings indicate that miR-125a-5p could modulate myeloid cell activation in the melanoma microenvironment via a NF-κB-dependent mechanism. [ABSTRACT FROM AUTHOR]

Myeloid-derived suppressor cells (MDSCs) have played a significant role in facilitating tumor immune escape and inducing an immunosuppressive tumor microenvironment. Eliminating MDSCs and tumor cells remains a major challenge in cancer immunotherapy. A novel approach has been developed using gemcitabine-celecoxib twin drug-based nano-assembled carrier-free nanoparticles (GEM-CXB NPs) for dual depletion of MDSCs and tumor cells in breast cancer chemoimmunotherapy. The GEM-CXB NPs exhibit prolonged blood circulation, leading to the preferential accumulation and co-release of GEM and CXB in tumors. This promotes synergistic chemotherapeutic activity by the proliferation inhibition and apoptosis induction against 4T1 tumor cells. In addition, it enhances tumor immunogenicity by immunogenic cell death induction and MDSC-induced immunosuppression alleviation through the depletion of MDSCs. These mechanisms synergistically activate the antitumor immune function of cytotoxic T cells and natural killer cells, inhibit the proliferation of regulatory T cells, and promote the M2 to M1 phenotype repolarization of tumor-associated macrophages, considerably enhancing the overall antitumor and anti-metastasis efficacy in BALB/c mice bearing 4T1 tumors. The simplified engineering of GEM-CXB NPs, with their dual depletion strategy targeting immunosuppressive cells and tumor cells, represents an advanced concept in cancer chemoimmunotherapy. [ABSTRACT FROM AUTHOR]

Acute pancreatitis (AP) is a complex inflammatory condition that can lead to systemic inflammatory responses and multiple organ dysfunction. This study investigates the role of Galectin-3 (Gal-3), a β-galactoside-binding lectin, in modulating acquired immune responses in AP. Acute pancreatitis was induced by ligation of the bile-pancreatic duct in wild-type and Galectin-3-deficient C57BL/6 mice. We determined the phenotypic and molecular features of inflammatory cells, serum concentrations of amylase, pancreatic trypsin activity, and pancreatic and lung pathology. Galectin-3 deficiency decreased the total number of CD3+CD49− T cells and CD4+ T helper cells, downregulated the production of inflammatory cytokine and IFN-γ, and increased the accumulation of IL-10-producing Foxp3+ T regulatory cells and regulatory CD4+ T cells in the pancreata of diseased animals. The deletion of Galectin-3 ameliorates acute pancreatitis characterized by lowering serum amylase concentration and pancreatic trypsin activity, and attenuating of the histopathology of the lung. These findings shed light on the role of Galectin-3 in acquired immune response in acute pancreatitis and identify Galectin-3 as an attractive target for investigation of the immunopathogenesis of disease and for consideration as a potential therapeutic target for patients with acute inflammatory disease of the pancreas. [ABSTRACT FROM AUTHOR]

Myeloid-derived suppressor cells (MDSCs) are recognized as major immune suppressor cells in the tumor microenvironment that may inhibit immune checkpoint blockade (ICB) therapy. Here, we developed a Stattic-loaded mesoporous silica nanoparticle (PEG-MSN-Stattic) delivery system to tumor sites to reduce the number of MDSCs in tumors. This approach is able to significantly deplete intratumoral MSDCs and thereby increase the infiltration of T lymphocytes in tumors to enhance ICB therapy. Our approach may provide a drug delivery strategy for regulating the tumor microenvironment and enhancing cancer immunotherapy efficacy. [ABSTRACT FROM AUTHOR]

Breast cancers (BCs) are solid tumors composed of heterogeneous tissues consisting of cancer cells and an ever-changing tumor microenvironment (TME). The TME includes, among other non-cancer cell types, immune cells influencing the immune context of cancer tissues. In particular, the cross talk of immune cells and their interactions with cancer cells dramatically influence BC dissemination, immunoediting, and the outcomes of cancer therapies. Tumor-infiltrating lymphocytes (TILs), tumor-associated macrophages (TAMs), and myeloid-derived suppressor cells (MDSCs) represent prominent immune cell populations of breast TMEs, and they have important roles in cancer immunoescape and dissemination. Therefore, in this article we review the features of TILs, TAMs, and MDSCs in BCs. Moreover, we highlight the mechanisms by which these immune cells remodel the immune TME and lead to breast cancer metastasis. [ABSTRACT FROM AUTHOR]

Anti-aging functional foods benefit the elderly. Telomeres are chromosomal ends that maintain genome stability extended by telomerase catalytic subunit TERT. Due to the end-replication problem, telomeres shorten after each cell cycle without telomerase in most human cells, and eventually the cell enters the senescence stage. Natural products can attenuate the aging process by increasing telomerase activity, such as TA-65. However, TA-65 is expensive. Other Chinese natural products may achieve comparable effects. Here, we found that Rosa roxburghii fruit extracts effectively increase TERT expression and telomerase activity in cultured human mesenchymal stem cells. Both R. roxburghii fruit extracts obtained by freeze-drying and spray-drying increased the activity of telomerase. R. roxburghii fruit extracts were able to reduce reactive oxygen species levels, enhance superoxide dismutase activity, and reduce DNA damage caused by oxidative stress or radiation. R. roxburghii fruit extracts promoted cell proliferation, improved senescent cell morphology, delayed replicative cellular senescence, attenuated cell cycle suppressors, and alleviated the senescence-associated secretory phenotype. Transcriptome and metabolic profiling revealed that R. roxburghii fruit extracts promote DNA replication and telomere maintenance pathways and decrease triglyceride levels. Overall, we provide a theoretical basis for the application of R. roxburghii fruit as an anti-aging product. [ABSTRACT FROM AUTHOR]

We previously reported that nano-pulse treatment (NPT), a pulsed power technology, resulted in 4T1-luc mammary tumor elimination and a strong in situ vaccination, thereby completely protecting tumor-free animals against a second live tumor challenge. The mechanism whereby NPT mounts effective antitumor immune responses in the 4T1 breast cancer predominantly immunosuppressive tumor microenvironment (TME) remains unanswered. In this study, orthotopic 4T1 mouse breast tumors were treated with NPT (100 ns, 50 kV/cm, 1000 pulses, 3 Hz). Blood, spleen, draining lymph nodes, and tumors were harvested at 4-h, 8-h, 1-day, 3-day, 7-day, and 3-month post-treatment intervals for the analysis of frequencies, death, and functional markers of various immune cells in addition to the suppressor function of regulatory T cells (Tregs). NPT was verified to elicit strong in situ vaccination (ISV) against breast cancer and promote both acute and long-term T cell memory. NPT abolished immunosuppressive dominance systemically and in the TME by substantially reducing Tregs, myeloid-derived suppressor cells (MDSCs), and tumor-associated macrophages (TAMs). NPT induced apoptosis in Tregs and TAMs. It also functionally diminished the Treg suppression capacity, explained by the downregulation of activation markers, particularly 4-1BB and TGFβ, and a phenotypic shift from predominantly activated (CD44+CD62L−) to naïve (CD44−CD62L+) Tregs. Importantly, NPT selectively induced apoptosis in activated Tregs and spared effector CD4+ and CD8+ T cells. These changes were followed by a concomitant rise in CD8+CD103+ tissue-resident memory T cells and TAM M1 polarization. These findings indicate that NPT effectively switches the TME and secondary lymphatic systems from an immunosuppressive to an immunostimulatory state, allowing cytotoxic T cell function and immune memory formation to eliminate cancer cells and account for the NPT in situ vaccination. [ABSTRACT FROM AUTHOR]

In our previous studies, a novel cryothermal therapy (CTT) was developed to induce systemic long-term anti-tumor immunity. Natural killer (NK) cells were found to play an important role in CTT-induced long-term immune-mediated tumor control at the late stage after CTT, but the underlying mechanism is unclear. Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells that have potent immunosuppressive effects on T cells and weaken the long-term benefits of immunotherapy. Consequently, overcoming MDSC immunosuppression is essential for maintaining the long-term efficacy of immunotherapy. In this study, we revealed that NK cells considerably diminish MDSC accumulation at the late stage after CTT, boost T cell production, increase T cell activation, and promote MDSC maturation, culminating in Th1-dominant CD4+ T cell differentiation and enhancing NK and CD8+ T cell cytotoxicity. Additionally, NK cells activate ERK signaling in MDSCs through NKG2D-ligand interaction to increase the activity of tumor necrosis factor (TNF)-α converting enzyme (TACE)-cleaved membrane TNF-α. Furthermore, Increased TACE activity releases more soluble TNF-α from MDSCs to promote MDSC maturation. In our studies, we propose a novel mechanism by which NK cells can overcome MDSC-induced immunosuppression and maintain CTT-induced persistent anti-tumor immunity, providing a prospective therapeutic option to improve the performance of cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Apart from their killer identity, natural killer (NK) cells have integral roles in shaping the tumor microenvironment. Through immune gene deconvolution, the present study revealed an interplay between NK cells and myeloid-derived suppressor cells (MDSCs) in nonresponders of immune checkpoint therapy. Given that the mechanisms governing the outcome of NK cell–to–myeloid cell interactions remain largely unknown, we sought to investigate the cross-talk between NK cells and suppressive myeloid cells. Upon contact with tumor-experienced NK cells, monocytes and neutrophils displayed increased expression of MDSC-related suppressive factors along with increased capacities to suppress T cells. These changes were accompanied by impaired antigen presentation by monocytes and increased ER stress response by neutrophils. In a cohort of patients with sarcoma and breast cancer, the production of interleukin-6 (IL-6) by tumor-infiltrating NK cells correlated with S100A8/9 and arginase-1 expression by MDSCs. At the same time, NK cell–derived IL-6 was associated with tumors with higher major histocompatibility complex class I expression, which we further validated with b2m-knockout (KO) tumor mice models. Similarly in syngeneic wild-type and IL-6 KO mouse models, we then demonstrated that the accumulation of MDSCs was influenced by the presence of such regulatory NK cells. Inhibition of the IL-6/signal transducer and activator of transcription 3 (STAT3) axis alleviated suppression of T cell responses, resulting in reduced tumor growth and metastatic dissemination. Together, these results characterize a critical NK cell–mediated mechanism that drives the development of MDSCs during tumor immune escape. Editor's summary: Myeloid-derived suppressor cells (MDSCs) are known to suppress antitumor immune responses, and the effect of natural killer (NK) cells on their development has been unclear. Here, Neo et al. have identified an inflammatory gene signature that correlated with higher NK cell abundance in nonresponders to immune checkpoint blockade. They identified a noncanonical mechanism by which tumor-associated NK cells were able to induce MDSCs to suppress the tumor microenvironment (TME). Understanding the effect of these NK cells on the TME could provide a new treatment avenue to improve response to immunotherapy. —Dorothy Hallberg [ABSTRACT FROM AUTHOR]

Background: Clear cell renal cell carcinoma (RCC) is the most common kidney tumor. The analysis from medical database showed that Scm-like with four MBT domains protein 2 (SFMBT2) was decreased in advanced clear cell RCC cases, and its downregulation was associated with the poor prognosis. This study aims to investigate the role of SFMBT2 in clear cell RCC. Methods: The expression of SFMBT2 in clear cell RCC specimens were determined by immunohistochemistry staining and western blot. The overexpression and knockdown of SFMBT2 was realized by infection of lentivirus loaded with SFMBT2 coding sequence or silencing fragment in 786-O and 769-P cells, and its effects on proliferation and metastasis were assessed by MTT, colony formation, flow cytometry, wound healing, transwell assay, xenograft and metastasis experiments in nude mice. The interaction of SFMBT2 with histone deacetylase 3 (HDAC3) and seven in absentia homolog 1 (SIAH1) was confirmed by co-immunoprecipitation. Results: In our study, SFMBT2 exhibited lower expression in clear cell RCC specimens with advanced stages than those with early stages. Overexpression of SFMBT2 inhibited the growth and metastasis of clear cell RCC cells, 786-O and 769-P, in vitro and in vivo, and its silencing displayed opposites effects. HDAC3 led to deacetylation of SFMBT2, and the HDAC3 inhibitor-induced acetylation prevented SFMBT2 from SIAH1-mediated ubiquitination modification and proteasome degradation. K687 in SFMBT2 protein molecule may be the key site for acetylation and ubiquitination. Conclusions: SFMBT2 exerted an anti-tumor role in clear cell RCC cells, and HDAC3-mediated deacetylation promoted SIAH1-controlled ubiquitination of SFMBT2. SFMBT2 may be considered as a novel clinical diagnostic marker and/or therapeutic target of clear cell RCC, and crosstalk between its post-translational modifications may provide novel insights for agent development. [ABSTRACT FROM AUTHOR]

BACKGROUND: Myelodysplastic syndrome has worse hazards of acute myeloid leukemia transformation, and some studies have revealed that immune infiltration plays a vital part in the two. Nevertheless, more studies are required to confirm the relationship between immune infiltration and related differentially expressed gene regulation. OBJECTIVE: To screen the differentially expressed genes with prognostic significance between myelodysplastic syndrome and acute myeloid leukemia by bioinformatics analysis and explore the possible roles and mechanisms among these differentially expressed genes and immune infiltration mechanisms in the occurrence and progression of diseases. METHODS: The differentially expressed genes were screened for bioinformatics analysis using the GEO datasets, and analyzed by DO, GO, KEGG and GSEA. The TCGA prognostic database was used to plot the K-M curves of differentially expressed genes and receiver operating characteristic curve analysis was applied to evaluate the clinical diagnostic performance. Finally, CIBERSORT analysis was used to intuitively demonstrate the correlation between critical prognostic genes and the distribution of immuno-infiltrated cells. RT-qPCR was employed to detect peripheral blood samples from healthy controls, myelodysplastic syndrome and acute myeloid leukemia patients so as to verify the crucial genes preliminarily. RESULTS AND CONCLUSION: (1) A total of 150 differentially expressed genes were obtained between myelodysplastic syndrome and acute myeloid leukemia, among which 16 genes were up-regulated and 134 were down-regulated. (2) The results of DO, GO, KEGG and GSEA analysis suggested that differentially expressed genes might promote the development of myelodysplastic syndrome to acute myeloid leukemia by regulating the immune response. CIBERSORT revealed the differences in immune infiltration between myelodysplastic syndrome and acute myeloid leukemia. The distribution of CD4+ T cells, monocytes, neutrophils and M1 macrophages decreased in acute myeloid leukemia patients. In contrast, the distribution of inflammatory suppressor cells M2 macrophages increased, suggesting that it may be related to the immunosuppression of acute myeloid leukemia. (3) K-M curve and receiver operating characteristic curve analysis of 150 differentially expressed genes screened out four genes relevant to immunity and prognosis with good diagnostic performance: MANSC1, FLT3, BMX and CXCR2. (4) The results of RT-qPCR exhibited that MANSC1, BMX and CXCR2 were low expressed, while FLT3 was highly expressed in acute myeloid leukemia patients. These findings verify that the differential expression of MANSC1, FLT3, BMX and CXCR2 in patients with myelodysplastic syndrome and acute myeloid leukemia is not only significantly correlated with the prognosis of patients but may also affect the occurrence and development of myelodysplastic syndrome and acute myeloid leukemia by regulating the immune infiltration of patients. They can be used as potential biomarkers and therapeutic targets of the transformation from myelodysplastic syndrome to acute myeloid leukemia, providing a new direction for clinical diagnosis and treatment of the transformation of myelodysplastic syndrome. [ABSTRACT FROM AUTHOR]

Clinical trials involving systemic neoadjuvant treatments in breast cancer aim to shrink tumors before surgery while simultaneously allowing for controlled evaluation of biomarkers, toxicity, and suppression of distant (occult) metastatic disease. Yet neoadjuvant clinical trials are rarely preceded by preclinical testing involving neoadjuvant treatment, surgery, and post-surgery monitoring of the disease. Here we used a mouse model of spontaneous metastasis occurring after surgical removal of orthotopically implanted primary tumors to develop a predictive mathematical model of neoadjuvant treatment response to sunitinib, a receptor tyrosine kinase inhibitor (RTKI). Treatment outcomes were used to validate a novel mathematical kinetics-pharmacodynamics model predictive of perioperative disease progression. Longitudinal measurements of presurgical primary tumor size and postsurgical metastatic burden were compiled using 128 mice receiving variable neoadjuvant treatment doses and schedules (released publicly at https://zenodo.org/records/10607753). A non-linear mixed-effects modeling approach quantified inter-animal variabilities in metastatic dynamics and survival, and machine-learning algorithms were applied to investigate the significance of several biomarkers at resection as predictors of individual kinetics. Biomarkers included circulating tumor- and immune-based cells (i.e., circulating tumor cells and myeloid-derived suppressor cells) as well as immunohistochemical tumor proteins (i.e., CD31 and Ki67). Our computational simulations show that neoadjuvant RTKI treatment inhibits primary tumor growth but has little efficacy in preventing (micro)-metastatic disease progression after surgery and treatment cessation. Machine learning algorithms that included support vector machines, random forests, and artificial neural networks, confirmed a lack of definitive biomarkers, which shows the value of preclinical modeling studies to identify potential failures that should be avoided clinically. Author summary: Using simulations from a mechanistic mathematical model compared with preclinical data from surgical metastasis models, we found that anti-tumor effects of neoadjuvant receptor tyrosine kinase inhibitor treatment can differ between the primary tumor and metastases in the perioperative setting. Model simulations with variable drug doses and scheduling of neoadjuvant treatment revealed a contrasting impact on initial primary tumor debulking and metastatic outcomes long after treatment has stopped and the primary tumor has been surgically removed. Using machine-learning algorithms, we identified the limited power of several circulating cellular and molecular biomarkers in predicting metastatic outcomes, uncovering a potential fast-track strategy for assessing future clinical biomarkers by pairing patient studies with identical studies in mice. [ABSTRACT FROM AUTHOR]

Cancer chemotherapy remains an area of concern, as many of the therapies are uncomfortable involving side effects and unpleasant experiences. These factors could further reduce patient’s quality of life, and even endanger their life. Many therapeutic strategies have been tried to reduce the unpleasant side effects and increase the treatment effectiveness; however, none have shown to have promising effects. One of the main hindrances to cancer therapy is the escape strategies by tumor cells to the immune attack. Promoting inflammation in the tumor microenvironment is the cornerstone and key therapeutic target in cancer chemotherapy. High‑salt diet (HSD) intake, though it has deleterious effects on human health by promoting chronic inflammation, is found to be advantageous in the tumor microenvironment. Studies identified HSD favors an increased abundance of Bifidobacterium species in the tumor environment due to gut barrier alteration, which, in turn, promotes inflammation and favors improved response to cancer chemotherapy. A review of the literature was carried out to find out the effects of an HSD on health and diseases, with special mention of its effect on cancer chemotherapy. Studies emphasized HSD would block the myeloid‑derived suppressor cells which will enhance the tumor immunity. Exploration of the precise mechanism of simple HSD regime/ingestion of specific bacterial species as probiotics will be effective and essential to formulate the game‑changing cancer chemotherapy. With the modern era of healthcare moving toward precision medicine where the physician can choose the treatment option suitable for the individual, HSD regime/ingestion of specific bacterial species can be considered. [ABSTRACT FROM AUTHOR]

We found that immunosuppressive monocytic-myeloid-derived suppressor cells (M-MDSCs) were more likely to be recruited by glioblastoma (GBM) through adhesion molecules on GBM-associated endothelial cells upregulated post-chemoradiotherapy. These cells are continuously generated during tumor progression, entering tumors and expressing PD-L1 at a high level, allowing GBM to exhaust T cells and evade attack from the immune system, thereby facilitating GBM relapse. αLy-6C-LAMP is composed of (i) drug cores with slightly negative charges condensed by cationic protamine and plasmids encoding PD-L1 trap protein, (ii) pre-formulated cationic liposomes targeted to Ly-6C for encapsulating the drug cores, and (iii) a layer of red blood cell membrane on the surface for effectuating long-circulation. αLy-6C-LAMP persistently targets peripheral, especially splenic, M-MDSCs and delivers secretory PD-L1 trap plasmids, leveraging M-MDSCs to transport the plasmids crossing the blood-brain barrier (BBB), thus expressing PD-L1 trap protein in tumors to inhibit PD-1/PD-L1 pathway. Our proposed drug delivery strategy involving intermediaries presents an efficient cross-BBB drug delivery concept that incorporates live-cell targeting and long-circulating nanotechnology to address GBM recurrence. [Display omitted] • Recurrence is inevitable after conventional treatment of glioblastoma. • Glioblastoma promotes MDSC recruitment by upregulating endothelial cell adhesion factors after chemoradiotherapy. • Recruitment of M-MDSCs after chemoradiotherapy results in long-term retention and promotes tumor survival and recurrence. • Long-circulating M-MDSCs-targeted drug delivery system enables trans-BBB drug delivery. [ABSTRACT FROM AUTHOR]