Tissue-resident FOLR2+ macrophages associate with CD8+ T cell infiltration in human breast cancer

Prenatally derived macrophages support choroidal health and decline in age-related macular degeneration

Hallmark findings in age-related macular degeneration (AMD) include the accumulation of extracellular lipid and vasodegeneration of the choriocapillaris. Choroidal inflammation has long been associated with AMD, but little is known about the immune landscape of the human choroid. Using 3D multiplex immunofluorescence, single-cell RNA sequencing, and flow cytometry, we unravel the cellular composition and spatial organization of the human choroid and the immune cells within it. We identify two populations of choroidal macrophages with distinct FOLR2 expression that account for the majority of myeloid cells. FOLR2+ macrophages predominate in the nondiseased eye, express lipid-handling machinery, uptake lipoprotein particles, and contain high amounts of lipid. In AMD, FOLR2+ macrophages are decreased in number and exhibit dysfunctional lipoprotein metabolism. In mice, FOLR2+ macrophages are negative for the postnatal fate-reporter Ms4a3, and their depletion causes an accelerated AMD-like phenotype. Our results show that prenatally derived resident macrophages decline in AMD and are implicated in multiple hallmark functions known to be compromised in the disease.

TREM2-expressing macrophages in liver diseases

Metabolic dysfunction-associated steatotic liver disease (MASLD) affects over 30% of the global population and spans a spectrum of liver abnormalities, including simple steatosis, inflammation, fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Recent studies have identified triggering receptors expressed on myeloid cells 2 (TREM2)-expressing macrophages as key regulators of MASLD progression. TREM2 plays a pivotal role in regulating macrophage-mediated processes such as efferocytosis, inflammatory control, and fibrosis resolution. Additionally, soluble TREM2 (sTREM2) was proposed as a noninvasive biomarker for diagnosing and monitoring MASLD progression. However, the molecular mechanisms through which TREM2 influences MASLD pathogenesis remain incompletely understood. This review summarizes the current understanding of TREM2-expressing macrophages in MASLD, with the goal of illuminating future research and guiding the development of innovative therapeutic strategies targeting TREM2 signaling pathways.

Research progress on monocyte/macrophage in the development of gastric cancer

Gastric cancer (GC) is diagnosed more than one million times each year and represents a major cause of cancer-related death worldwide. Although GC presents as a group of different types of disease, chronic inflammation has been strongly associated with tumorigenesis. Monocyte/macrophage play important roles in the development of inflammation and are vital components of the tumor microenvironment (TME). Monocyte/macrophage exert protumor and/or antitumor effects through the release of angiogenic and lymphangiogenic factors. Furthermore, tumor associated macrophages (TAMs) are emerging as key players in GC development. It is necessary to review and elucidate the roles of TAM subsets in GC and their molecular features. In this study, we focused on GC-related subsets of monocytes/macrophages and analyzed signaling related to TAMs in GC as well as the potential roles of these cells as therapeutic targets.

Roles of macrophages and monocytes in resistance to immunotherapy in breast cancers

BACKGROUND

Immunotherapy is increasingly integral to breast cancer treatment, yet a subset develops resistance, partly mediated by macrophages and monocytes in the tumor immune microenvironment. While macrophages play essential roles in phagocytosis and pathogen clearance, their dual role in breast cancer-acting as both barriers to therapy and potential therapeutic targets-complicates treatment efficacy.

STRATEGY

Tumor-associated macrophages, polarized by tumor-derived signals, promote cancer progression and metastasis. Monocytes, subdivided into CD14+CD16- and CD14+CD16+ subsets, exhibit distinct functional profiles in cytokine secretion, antigen presentation, and migration. Modulating monocyte subset dynamics and functionality may enhance immunotherapy responsiveness.

CONCLUSION

A multimodal strategy targeting macrophages, monocytes, and complementary immunotherapies offers promising avenues to overcome resistance. Further research into the heterogeneity and regulatory mechanisms of these cells is critical for developing optimized, safe immunotherapeutic protocols. This review underscores the necessity of combination immunotherapies to improve outcomes in breast cancer.

AXL promotes inflammatory breast cancer progression by regulating immunosuppressive macrophage polarization

BACKGROUND

Tumor-associated macrophages (TAMs) are key promoters of inflammatory breast cancer (IBC), the most aggressive form of breast cancer. The receptor tyrosine kinase AXL is highly expressed in various cancer types, including IBC, but its role in TAMs remains unexplored.

METHODS

We examined the effects of AXL inhibitor TP-0903 on tumor growth and tumor microenvironment (TME) component M2 macrophages (CD206+) in IBC and triple-negative breast cancer mouse models using flow cytometry and immunohistochemical staining. Additionally, we knocked out AXL expression in human THP-1 monocytes and evaluated the effect of AXL signaling on immunosuppressive M2 macrophage polarization and IBC cell growth and migration. We then investigated the underlying mechanisms through RNA sequencing analysis. Last, we performed CIBERSORT deconvolution to analyze the association between AXL expression and tumor-infiltrating immune cell types in tumor samples from the Inflammatory Breast Cancer International Consortium.

RESULTS

We found that inhibiting the AXL pathway significantly reduced IBC tumor growth and decreased CD206+ macrophage populations within tumors. Mechanistically, our in vitro data showed that AXL promoted M2 macrophage polarization and enhanced the secretion of immunosuppressive chemokines, including CCL20, CCL26, and epiregulin, via the transcription factor STAT6 and thereby accelerated IBC cell growth and migration. RNA sequencing analysis further indicated that AXL signaling in immunosuppressive M2 macrophages regulated the expression of molecules and cytokines, contributing to an immunosuppressive TME in IBC. Moreover, high AXL expression was correlated with larger populations of immunosuppressive immune cells but smaller populations of immunoactive immune cells in tissues from patients with IBC.

CONCLUSIONS

AXL signaling promotes IBC growth by inducing M2 macrophage polarization and driving the secretion of immunosuppressive molecules and cytokines via STAT6 signaling, thereby contributing to an immunosuppressive TME. Collectively, these findings highlight the potential of targeting AXL signaling as a novel therapeutic approach for IBC that warrants further investigation in clinical trials.

Understanding the Dual Role of Macrophages in Tumor Growth and Therapy: A Mechanistic Review

Macrophages are heterogeneous cells that are the mediators of tissue homeostasis. These immune cells originated from monocytes and are classified into two basic categories, M1 and M2 macrophages. M1 macrophages exhibit anti-tumorous inflammatory reactions due to the behavior of phagocytosis. M2 macrophages or tumor-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment (TME) and have a basic role in tumor progression by interacting with other immune cells in TME. By the expression of various cytokines, chemokines, and growth factors, TAMs lead to strengthening tumor cell proliferation, angiogenesis, and suppression of the immune system which further support invasion and metastasis. This review discusses recent and updated mechanisms regarding tumor progression by M2 macrophages. Moreover, the current therapeutic approaches targeting TAMs, their advantages, and limitations are also summarized, and further treatment approaches are outlined along with an elaboration of the tumor regression role of macrophages. This comprehensive review article possibly helps to understand the mechanisms underlying the tumor progression and regression role of macrophages in a comparative way from a basic level to the advanced one.

Integrative multi-omics and Mendelian randomization analysis reveal SPP1+ tumor-associated macrophage-driven prognostic signature for hepatocellular carcinoma

Background

The SPP1+ tumor-associated macrophages (TAMs) have been implicated in tumor metastasis and immune evasion. However, the prognostic significance of SPP1+ TAMs in hepatocellular carcinoma (HCC) remains largely unexplored. This study aimed to identify SPP1+ TAMs-related genes and construct a model to predict overall survival (OS) in HCC patients.

Methods

Single-cell RNA sequencing (scRNA-seq) datasets from HCC patients were analyzed to identify SPP1+ TAMs. SPP1+ TAMs-related risk score (STRS) was developed using Mendelian randomization (MR) analysis and Least Absolute Shrinkage and Selection Operator (LASSO) regression. HCC patients from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) cohorts were stratified into high- and low-STRS groups based on STRS. Kaplan-Meier survival analysis, receiver operating characteristic (ROC) curve analysis, and functional enrichment analysis were performed to assess the prognostic value of STRS.

Results

SPP1+ TAMs exhibited strong associations with immunosuppressive functions. 16 SPP1+ TAMs-related genes were used to construct STRS. Patients in the high-STRS group had significantly worse OS than those in the low-STRS group (p < 0.001). ROC analysis demonstrated robust predictive power, with AUC values ranging from 0.685 to 0.748 for 1-year OS, 0.717 to 0.739 for 2-year OS, and 0.719 to 0.738 for 3-year OS. The STRS model also exhibited strong predictive capability for the distinction of drug resistance.

Conclusion

This study identified SPP1+ TAMs-related genes as key prognostic indicators in HCC. The STRS model provides an effective tool for predicting patient survival and may facilitate personalized treatment strategies for HCC. These findings enhance the understanding of TAMs-driven immune modulation in HCC and highlight potential therapeutic targets for improving patient outcomes.

IL-1β+ macrophages and the control of pathogenic inflammation in cancer

While highlighting the complexity and heterogeneity of tumor immune microenvironments, the application of single-cell analyses in human cancers has identified recurrent subsets of tumor-associated macrophages (TAMs). Among these, interleukin (IL)-1β+ TAMs - cells with high levels of expression of inflammatory response and tissue repair genes, but with limited capacity to stimulate cytotoxic immunity - are emerging as key drivers of pathogenic inflammation in cancer. In this review we discuss recent literature defining the phenotypical, molecular, and functional properties of IL-1β+ TAMs, as well as their temporal dynamics and spatial organization. Elucidating the biology of these cells across tumor initiation, progression, metastasis, and therapy could inform the design and interpretation of clinical trials targeting IL-1β and/or other inflammatory factors in cancer immunotherapy.

Palbociclib stimulates CD8+ T cell response in triple-negative breast cancer via regulating phosphoglycerate dehydrogenase

CDK4/6 inhibitors are applied for the treatment of breast cancer. The purpose of this study was to explore the effects of palbociclib (PALB) on triple-negative breast cancer. An in vivo assay was applied to determine the effects of PALB on breast cancer. Gene expression was detected using immunohistochemistry. mRNA levels were detected using reverse transcription-quantitative PCR. Protein expression was detected using western blot. The expansion of CD8+ T cell subsets was detected using flow cytometry. We found that PALB treatment promoted the persistence of CD8+ T cells, manifested by the maintenance of stem-like CD8+ T cells and effector T cells. Moreover, PALB downregulated PHGDH, high levels of which predicted poor prognosis of breast cancer patients. Moreover, overexpression of PHGDH antagonized the effects of PALB and suppressed the persistence of CD8+ T cells. Additionally, PALB enhanced the effects of anti-PD1 immunotherapy and suppressed the tumor growth of breast cancer. In summary, PALB promoted the maintenance of CD8+ memory precursors in breast cancer via downregulating PHGDH.

Targeting VSIG4+ tissue-resident macrophages enhances T cell cytotoxicity and immunotherapy efficacy in cancer

Tissue-resident macrophage (TRM) is crucial for organ development and homeostasis. However, the role of TRM-derived tumor-associated macrophage (TAM) subpopulations in cancer remains unclear. Using single-cell RNA sequencing and lineage tracing, we reported a TRM-derived TAM subpopulation, characterized by VSIG4 overexpression in testicular cancer. Macroscopically, such subpopulation was also found in tumors such as hepatocellular carcinoma, lung cancer, and glioblastoma. It was associated with poor prognosis and the suppression of CD8+ T-cell-dependent immunity via VSIG4. Notably, VSIG4 promoted immunosuppressive effects through direct or indirect modes, including interacting with receptors on CD8+ T cells or inducing transcription of IL-11 in TAMs. More importantly, MEF2C was identified as a key transcription factor that maintained VSIG4 expression and determined the biological behaviors of VSIG4+ TAMs. In preclinical models, targeting VSIG4+ TAMs via VSIG4 or MEF2C demonstrated a favorable effect of enhancing the efficacy of immune checkpoint inhibitors.

Nutritional Strategies in Oncology: A Narrative Review of Advances in Folate-Targeted Therapeutic Approaches for Cancer Treatment

Folate, a water-soluble B vitamin crucial for DNA synthesis and repair, is internalized by cells through specific folate receptors (FRs), which are frequently overexpressed in various types of cancers. In this comprehensive study, we conducted a review of the literature from Google Scholar, PubMed, and Science Direct, focusing on research published between 1980 and 2024 to evaluate folate-targeted therapeutic strategies in oncology. Our study design involved a rigorous review of both preclinical and clinical research, emphasizing strategies such as folate-drug conjugates, antibody-drug conjugates, and folate-targeted nanoparticles. Key findings indicate that targeting FRs in cancers such as ovarian, breast, cervical, renal, and colorectal enhances drug delivery specificity to tumors, increases therapeutic efficacy, and decreases systemic toxicity compared to traditional chemotherapy. Several clinical trials reported improved progression-free survival and overall response rates among patients receiving folate-targeted therapies. In conclusion, our review highlights the significant potential of folate-targeted strategies in advancing precision oncology while these approaches provide substantial benefits in terms of efficacy and safety, further research is essential to refine drug design and expand clinical applications. Such initiatives will facilitate the development of more personalized cancer treatment protocols that maximize therapeutic outcomes while minimizing adverse effects.

Mapping immune cell dynamics and macrophage plasticity in breast cancer tumor microenvironment through single-cell analysis

Breast cancer (BRCA) is a complex disease influenced by the tumor microenvironment, where interactions between immune cells and cancer cells play a crucial role in tumor progression and response to therapy. Understanding the intricacies of these interactions requires detailed analysis at the single-cell level, enabling the identification of specific immune cell subpopulations and their functional roles within the tumor milieu. This study comprehensively analyzed immune cell subpopulations and macrophage subtypes in BRCA using single-cell RNA sequencing technology and various computational tools. Initially, Sc-Type software accurately identified and annotated immune cell subpopulations, followed by CNV analysis using infercnv software, revealing significant CNV variations in epithelial cells. Subsequently, macrophages were re-clustered into 5 clusters, and their biological significance and functional features were assessed. CellChat analysis elucidated potential interactions between macrophage subtypes and BRCA cells, primarily through SPP1-CD44 and LGALS9-CD44 signaling networks. Additionally, CytoTRACE and Monocle were employed to analyze cellular plasticity and differentiation trajectories of macrophage subtypes. Furthermore, efferocytosis-related gene set scoring, transcription factor analysis, and risk score development were conducted, followed by immune infiltration and tumor mutation burden analysis, revealing increased immune infiltration and higher TMB levels in the high-risk group. These findings offer crucial insights into the interaction mechanisms of immune cells and macrophage subtypes within the BRCA tumor microenvironment, aiding in the understanding of tumor progression and therapeutic interventions.

O-Desmethyltramadol Enhanced Anti-Cancer Efficacy over Tramadol Through Non-μ-Opioid Receptor and Differential Cellular Contexts of Human Breast Cancer Cells

Tramadol, a widely used analgesic, has recently been explored for its potential anti-cancer effects. However, the antitumor dosage of tramadol is over its current clinical application. Its primary metabolite, O-desmethyltramadol, has greater μ-opioid receptor affinity and stronger pharmacological activity. Hence, we sought to examine whether the cytotoxic effect of O-desmethyltramadol was better than tramadol on breast cancer cells. Our results showed that O-desmethyltramadol significantly reduced cell viability in breast cancer cells, with IC50 values of 64.2 μg/mL (MDA-MB-231) and 96.7 μg/mL (MCF-7), demonstrating over ten-fold greater potency than tramadol. The presence of a μ-opioid receptor antagonist Alvimopan did not alter the cytotoxic effects of tramadol and O-desmethyltramadol, indicating a non-opioid receptor-mediated mechanism. Compared with antitumor activity of tramadol mediated through ER stress, we confirmed that O-desmethyltramadol induced ER stress proteins, including the p-eIF2α/eIF2α ratio, ATF4, and CHOP. In MDA-MB-231 cells, O-desmethyltramadol treatment elevated mRNA expression levels of ATF4, CHAC1, and DDIT3 by approximately 2-fold. In MCF-7 cells, the induction was even more pronounced, with ATF4 increased 1.7-fold, CHAC1 12-fold, and DDIT3 9-fold. Beyond the opioid receptor-mediated pathway, we further analyzed the differential functions of O-desmethyltramadol than tramadol using the RNA-seq analysis. The pathway enrichment analyses revealed that O-desmethyltramadol influenced immune and inflammatory pathways, such as TNF and IL-6/JAK/STAT3 signaling in MDA-MB-231 cells, while in MCF-7 cells, it affected metabolic and transcriptional pathways, including mTOR and MAPK signaling. Gene Set Enrichment Analysis further highlighted O-desmethyltramadol's role in interferon response and tumor microenvironment modulation. Four upregulated genes and five downregulated genes were modulated by O-desmethyltramadol in MDA-MB-231 and MCF-7 cells. Overall, our findings indicated that O-desmethyltramadol exerted potent anti-cancer effects through multiple non-opioid mechanisms, with distinct response from tramadol depending on breast cancer subtype. These findings not only highlight the therapeutic potential of O-desmethyltramadol as a novel adjunct in breast cancer treatment, but also emphasize the need for further investigation into its safety and clinical applicability in oncology.

Macrophage-derived exosomes in cancer: a double-edged sword with therapeutic potential

Solid cancer contains a complicated communication network between cancer cells and components in the tumor microenvironment (TME), significantly influencing the progression of cancer. Exosomes function as key carriers of signaling molecules in these communications, including the intricate signalings of tumor-associated macrophages (TAMs) on cancer cells and the TME. With their natural lipid bilayer structures and biological activity that relates to their original cell, exosomes have emerged as efficient carriers in studies on cancer therapy. Intrigued by the heterogeneity and plasticity of both macrophages and exosomes, we regard macrophage-derived exosomes in cancer as a double-edged sword. For instance, TAM-derived exosomes, educated by the TME, can promote resistance to cancer therapies, while macrophage-derived exosomes generated in vitro have shown favorable potential in cancer therapy. Here, we depict the reasons for the heterogeneity of TAM-derived exosomes, as well as the manifold roles of TAM-derived exosomes in cancer progression, metastasis, and resistance to cancer therapy. In particular, we emphasize the recent advancements of modified macrophage-derived exosomes in diverse cancer therapies, arguing that these modified exosomes are endowed with unique advantages by their macrophage origin. We outline the challenges in translating these scientific discoveries into clinical cancer therapy, aiming to provide patients with safe and effective treatments.

Mapping the spatial architecture of glioblastoma from core to edge delineates niche-specific tumor cell states and intercellular interactions

Treatment resistance in glioblastoma (GBM) is largely driven by the extensive multi-level heterogeneity that typifies this disease. Despite significant progress toward elucidating GBM's genomic and transcriptional heterogeneity, a critical knowledge gap remains in defining this heterogeneity at the spatial level. To address this, we employed spatial transcriptomics to map the architecture of the GBM ecosystem. This revealed tumor cell states that are jointly defined by gene expression and spatial localization, and multicellular niches whose composition varies along the tumor core-edge axis. Ligand-receptor interaction analysis uncovered a complex network of intercellular communication, including niche- and region-specific interactions. Finally, we found that CD8 positive GZMK positive T cells colocalize with LYVE1 positive CD163 positive myeloid cells in vascular regions, suggesting a potential mechanism for immune evasion. These findings provide novel insights into the GBM tumor microenvironment, highlighting previously unrecognized patterns of spatial organization and intercellular interactions, and novel therapeutic avenues to disrupt tumor-promoting interactions and overcome immune resistance.

Peritoneal resident macrophages constitute an immunosuppressive environment in peritoneal metastasized colorectal cancer

Patients with peritoneal metastasized colorectal cancer (PM-CRC) have a dismal prognosis. We hypothesized that an immunosuppressive environment in the peritoneal cavity underlies poor prognosis. We define the composition of the human peritoneal immune system (PerIS) using single-cell technologies in 18 patients with- and without PM-CRC, as well as in matched peritoneal metastases (n = 8). Here we show that the PerIS contains abundant immunosuppressive C1Q+VSIG4+ and SPP1+VSIG4+ peritoneal-resident macrophages (PRMs), as well as monocyte-like cavity macrophages (mono-CMs), which share features with tumor-associated macrophages, even in homeostasis. In PM-CRC, expression of immunosuppressive cytokines IL10 and VEGF increases, while simultaneously expression of antigen-presenting molecules decreases in PRMs. These intratumoral suppressive PRMs originate from the PerIS, and intraperitoneal depletion of PRMs in vivo using anti-CSF1R combined with anti-PD1 significantly reduces tumor burden and improves survival. Thus, PRMs define a metastatic site-specific immunosuppressive niche, and targeting PRMs is a promising treatment strategy for PM-CRC.

Senescence-induced p21high macrophages contributed to CD8+ T cells-related immune hyporesponsiveness in kidney transplantation via Zfp36/IL-27 axis

Recipients' age has emerged as a key factor that impacts on acute renal allograft rejection and graft survival. Age-related functional and structural changes in the immune system have been observed, yet the precise influence of aged immunity on kidney transplant remains unclear. In an initial retrospective analysis of clinical data gathered from two major centers in China and Germany, we found a correlation between aging and mitigated rejection outcomes in kidney recipients. To study the mechanism, we performed kidney transplantation on mice and observed attenuated allograft rejection in senescent recipients. Single-cell transcriptome analysis of allograft kidneys indicated a protective role of p21high macrophages in aged mice. Supernatant collected from p21high macrophage primary culture inhibited the cytotoxic function and proliferation of CD8+ T cells. Zfp36 is highly expressed in senescent p21high macrophages. To determine its role in renal allograft rejection, we studied mice with Zfp36 conditionally deleted in macrophages (Zfp36-cKO). These mice developed exacerbated allograft rejection with enhanced IL-27 production and CD8+ T cell hyperactivation. Inhibition of IL-27 with neutralizing antibody or deletion of IL-27 receptor on CD8+ T cells reversed acute renal allograft rejection in Zfp36-cKO mice. Moreover, in vitro silencing Zfp36 with siRNA led to impaired degradation of IL-27 p28 mRNA and a subsequent increase of IL-27 in p21high macrophages. In conclusion, senescent macrophages protect renal allograft rejection by suppressing CD8+ T cells via a Zfp36/IL-27-dependent mechanism. These findings may provide innovative therapeutic strategies for addressing kidney allograft rejection.

Identification of M1 macrophage infiltration-related genes for immunotherapy in Her2-positive breast cancer based on bioinformatics analysis and machine learning

Over the past several decades, there has been a significant increase in the number of breast cancer patients. Among the four subtypes of breast cancer, Her2-positive breast cancer is one of the most aggressive breast cancers. In this study, we screened the differentially expressed genes from The Cancer Genome Atlas-Breast cancer database and analyzed the relationship between immune cell infiltration and differentially expressed genes using weighted gene co-expression network analysis. By constructing a module-trait relationships heatmap, the red module, which had the highest correlation value with M1 macrophages, was selected. Twenty hub genes were selected based on a protein-protein interaction network. Then, four overlapping M1 macrophage infiltration-related genes (M1 MIRGs), namely CCDC69, PPP1R16B, IL21R, and FOXP3, were obtained using five machine-learning algorithms. Subsequently, nomogram models were constructed to predict the incidence of Her2-positive breast cancer patients. The outer datasets and receiver operating characteristic curve analysis were used to validate the accuracy of the four M1 MIRGs and nomogram models. The average value of the area under the curve for the nomogram models was higher than 0.75 in both the training and testing sets. After that, survival analysis showed that higher expression of CCDC69, PPP1R16B, and IL21R were associated with overall survival of Her2-positive breast cancer patients. The expression of CCDC69 and PPP1R16B could lead to more benefits than the expression of IL21R and FOXP3 for immunotherapy. Lastly, we conducted immunohistochemistry staining to validate the aforementioned results. In conclusion, we found four M1 MIRGs that may be helpful for the diagnosis, prognosis, and immunotherapy of Her2-positive breast cancer.

Tertiary lymphoid structures associated with improved survival and enhanced antitumor immunity in acral melanoma

Understanding the impact of tertiary lymphoid structures (TLSs) on acral melanoma (AM) and the tumor microenvironment (TME) is critical. We analyzed TLS features in primary AM lesions from 46 patients and identified intratumoral TLSs (intra-TLSs) in 25 patients. Intra-TLS presence was significantly associated with improved overall survival. Hematoxylin and eosin staining and multiplex immunofluorescence revealed increased T-cell and CD8+ T-cell infiltration and fewer tumor-associated macrophages in the TME of intra-TLS patients. Transcriptomic analysis identified a TLS-associated Th1/B-cell gene set as a predictor of survival and immunotherapy response. These findings highlight the prognostic value of intra-TLSs in AMs and suggest that targeting TLS formation could enhance immunotherapy efficacy.

Hepatocellular carcinoma: pathogenesis, molecular mechanisms, and treatment advances

Hepatocellular Carcinoma (HCC), a highly prevalent malignancy, poses a significant global health challenge. Its pathogenesis is intricate and multifactorial, involving a complex interplay of environmental and genetic factors. Viral hepatitis, excessive alcohol consumption, and cirrhosis are known to significantly elevate the risk of developing HCC. The underlying biological processes driving HCC are equally complex, encompassing aberrant activation of molecular signaling pathways, dysregulation of hepatocellular differentiation and angiogenesis, and immune dysfunction. This review delves into the multifaceted nature of HCC, exploring its etiology and the intricate molecular signaling pathways involved in its development. We examine the role of immune dysregulation in HCC progression and discuss the potential of emerging therapeutic strategies, including immune-targeted therapy and tumor-associated macrophage interventions. Additionally, we explore the potential of traditional Chinese medicine (TCM) monomers in inhibiting tumor growth. By elucidating the complex interplay of factors contributing to HCC, this review aims to provide a comprehensive understanding of the disease and highlight promising avenues for future research and therapeutic development.

β-blocker suppresses both tumoral sympathetic neurons and perivascular macrophages during oncolytic herpes virotherapy

BACKGROUND

The autonomic nervous system (ANS) plays a key role in regulating tumor development and therapy resistance in various solid tumors. Within the ANS, the sympathetic nervous system (SNS) is typically associated with protumor effects. However, whether the SNS influences the antitumor efficacy of intratumoral injections of oncolytic herpes simplex virus (oHSV) in solid tumors remains unknown.

METHODS

In this study, we examined SNS innervation and its interaction with immune cell infiltration in both human and murine triple-negative breast cancer models during intratumoral oHSV injections and SNS blockade on oHSV's antitumor activity.

RESULTS

Intratumor oHSV injection promotes SNS innervation accompanied by CD45+cell infiltration in both the human MDA-MB-468 orthotopic model and the murine 4T1 mammary tumor model. Mechanistically, tumor-secreted factors vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and transforming growth factor beta (TGF-β) and transcription factors (CREB, AP-1, MeCP2, and REST), which promote SNS innervation, were found to be upregulated in oHSV-treated tumors. Combining the SNS antagonist, a β-blocker, with oHSV significantly increased immune cell infiltration, particularly CD8+T cells in oHSV-treated 4T1 tumors. Single-cell messenger RNA sequencing revealed that oHSV injection upregulated a specific population of perivascular macrophages (pvMacs) expressing high levels of VEGFA, CD206, CCL3, and CCL4, which suppress T-cell activation. The use of a β-blocker reduced the infiltration of oHSV-induced pvMacs, transition to inflammatory macrophages expressing Hexb, enhancing the diversity of T-cell receptor clonotypes. Further analysis suggested that TGF-β signaling within the tumor partially mediates SNS activation in the 4T1 model.

CONCLUSION

Our findings demonstrate that combining a β-blocker with oHSV significantly enhances the antitumor efficacy of oHSV in breast cancer by targeting TGF-β-mediated SNS innervation and immunosuppression.

Targeting SCD triggers lipotoxicity of cancer cells and enhances anti-tumor immunity in breast cancer brain metastasis mouse models

Breast cancer brain metastases (BCBM) are incurable, and new therapies are urgently needed. BCBM upregulates stearoyl-CoA desaturase (SCD), an enzyme that catalyzes the synthesis of monounsaturated fatty acids, suggesting a potential metabolic vulnerability. Here, we test the effect of a brain-penetrant, clinical-stage SCD inhibitor (SCDi) on breast cancer cells and mouse models of BCBM. We show that SCDi markedly reshapes the lipidome of breast cancer cells, resulting in endoplasmic reticulum stress, DNA damage, impaired DNA damage repair, and cytotoxicity. Importantly, SCDi alone or combined with a PARP inhibitor prolongs the survival of BCBM-bearing mice. Furthermore, pharmacological inhibition of SCD enhances antigen presentation by dendritic cells, increases interferon signaling, promotes the infiltration of cytotoxic T cells, and decreases the proportion of exhausted T cells and regulatory T cells (Tregs) in the tumor microenvironment (TME) in a syngeneic mouse model of BCBM. Additionally, SCDi reduces the engagement of immunosuppressive pathways, including the PD-1:PD-L1/PD-L2 and PVR/TIGIT axes in the TME. These findings suggest that SCD inhibition could be an effective strategy to both intrinsically reduce tumor growth and reprogram anti-tumor immunity in the brain microenvironment to treat BCBM.

Comparison of Lean, Obese, and Weight-Loss Models Reveals TREM2 Deficiency Attenuates Breast Cancer Growth Uniquely in Lean Mice and Alters Clonal T-cell Populations

Obesity is an established risk factor for breast cancer development and poor prognosis. The adipose environment surrounding breast tumors, which is inflamed in obesity, has been implicated in tumor progression, and triggering receptor expressed on myeloid cells 2 (TREM2), a transmembrane receptor expressed on macrophages in adipose tissue and tumors, is an emerging therapeutic target for cancer. A better understanding of the mechanisms for the obesity-breast cancer association and the potential benefits of weight loss could help inform treatment strategies. In this study, we utilized lean, obese, and weight-loss mouse models to examine the impact of TREM2 deficiency on postmenopausal breast cancer depending on weight history conditions. Trem2 deficiency constrained tumor growth in lean, but not in obese or weight-loss, mice. Single-cell RNA sequencing, in conjunction with variable-diversity-joining sequencing, of tumor and tumor-adjacent mammary adipose tissue immune cells revealed differences in the immune landscapes across the different models. Tumors of lean TREM2-deficient mice exhibited a shift in clonal CD8+ T cells from an exhausted to an effector memory state, accompanied by increased clonality of CD4+ Th1 cells, that was not observed in any other diet-genotype group. Notably, identical T-cell clonotypes were identified in the tumor and tumor-adjacent mammary adipose tissue of the same mouse. Finally, anti-PD-1 therapy restricted tumor growth in lean and weight-loss, but not in obese, mice. These findings indicate that weight history could affect the efficacy of TREM2 inhibition in postmenopausal breast cancer. The reported immunologic interactions between tumors and the surrounding adipose tissue highlight significant differences under obese and weight-loss conditions. Significance: Weight history impacts the immunological landscape of postmenopausal breast cancer and the efficacy of TREM2 modulation and anti-PD-1 therapy, which has implications for personalized medicine.

Embracing diversity: macrophage complexity in cancer

Macrophages are myeloid cells that receive, integrate, and respond to tumoral cues. Tumors evolve and are shaped by macrophages, with tumor-associated macrophage (TAM)-tumor sculpting capacities going beyond an increase in their cellular mass. Longitudinal and local heterogeneity of TAM states is now possible with the use of single-cell and spatial transcriptomics. However, understanding TAM biology and its fundamental functional programs is still challenging, probably because of the lack of models that fully integrate TAM complexity. Here, we aim to review TAM diversity not only at the level of single-cell phenotypes but also by integrating complex physiological signals that determine their complexity and plasticity in tumors.

Tumor Microenvironment On-A-Chip and Single-Cell Analysis Reveal Synergistic Stromal-Immune Crosstalk on Breast Cancer Progression

Solid tumors develop within a complex environment called the tumor microenvironment (TME), which is sculpted by the presence of other cells, such as cancer-associated fibroblasts (CAFs) and immune cells like macrophages (Mφs). Despite the presence of immune cells, tumor cells orchestrate a tumor-supportive environment through intricate interaction with the components of the TME. However, the specific mechanism by which this intercellular dialogue is regulated is not fully understood. To that end, the development of an organotypic 3D breast TME-on-a-chip (TMEC) model, integrated with single-cell RNA sequencing analysis, is reported to mechanistically evaluate the progression of triple-negative breast cancer (TNBC) cells in the presence of patient-derived CAFs and Mφs. Extensive functional assays, including invasion and morphometric characterization, reveal the synergistic influence of CAFs and Mφs on tumor cells. Furthermore, gene expression and pathway enrichment analyses identify the involvement of the KYNU gene, suggesting a potential immune evasion mechanism through the kynurenine pathway. Lastly, the pharmacological targeting of the identified pathway is investigated.

Myeloid cells: key players in tumor microenvironments

Cancer is the result of evolving crosstalk between neoplastic cell and its immune microenvironment. In recent years, immune therapeutics targeting T lymphocytes, such as immune checkpoint blockade (ICB) and CAR-T, have made significant progress in cancer treatment and validated targeting immune cells as a promising approach to fight human cancers. However, responsiveness to the current immune therapeutic agents is limited to only a small proportion of solid cancer patients. As major components of most solid tumors, myeloid cells played critical roles in regulating the initiation and sustentation of adaptive immunity, thus determining tumor progression as well as therapeutic responses. In this review, we discuss emerging data on the diverse functions of myeloid cells in tumor progression through their direct effects or interactions with other immune cells. We explain how different metabolic reprogramming impacts the characteristics and functions of tumor myeloid cells, and discuss recent progress in revealing different mechanisms-chemotaxis, proliferation, survival, and alternative sources-involved in the infiltration and accumulation of myeloid cells within tumors. Further understanding of the function and regulation of myeloid cells is important for the development of novel strategies for therapeutic exploitation in cancer.

Deciphering the preeclampsia-specific immune microenvironment and the role of pro-inflammatory macrophages at the maternal-fetal interface

Preeclampsia (PE), a major cause of maternal and perinatal mortality with highly heterogeneous causes and symptoms, is usually complicated by gestational diabetes mellitus (GDM). However, a comprehensive understanding of the immune microenvironment in the placenta of PE and the differences between PE and GDM is still lacking. In this study, cytometry by time of flight indicated that the frequencies of memory-like Th17 cells (CD45RA-CCR7+IL-17A+CD4+), memory-like CD8+ T cells (CD38+CXCR3-CCR7+Helios-CD127-CD8+) and pro-inflam Macs (CD206-CD163-CD38midCD107alowCD86midHLA-DRmidCD14+) were increased, while the frequencies of anti-inflam Macs (CD206+CD163-CD86midCD33+HLA-DR+CD14+) and granulocyte myeloid-derived suppressor cells (gMDSCs, CD11b+CD15hiHLA-DRlow) were decreased in the placenta of PE compared with that of normal pregnancy (NP), but not in that of GDM or GDM&PE. The pro-inflam Macs were positively correlated with memory-like Th17 cells and memory-like CD8+ T cells but negatively correlated with gMDSCs. Single-cell RNA sequencing revealed that transferring the F4/80+CD206- pro-inflam Macs with a Folr2+Ccl7+Ccl8+C1qa+C1qb+C1qc+ phenotype from the uterus of PE mice to normal pregnant mice induced the production of memory-like IL-17a+Rora+Il1r1+TNF+Cxcr6+S100a4+CD44+ Th17 cells via IGF1-IGF1R, which contributed to the development and recurrence of PE. Pro-inflam Macs also induced the production of memory-like CD8+ T cells but inhibited the production of Ly6g+S100a8+S100a9+Retnlg+Wfdc21+ gMDSCs at the maternal-fetal interface, leading to PE-like symptoms in mice. In conclusion, this study revealed the PE-specific immune cell network, which was regulated by pro-inflam Macs, providing new ideas about the pathogenesis of PE.

Genetic analysis reveals the shared genetic architecture between breast cancer and atrial fibrillation

Background

Epidemiological studies have observed an association between atrial fibrillation (AF) and breast cancer (BC). However, the underlying mechanisms linking these two conditions remain unclear. This study aims to systematically explore the genetic association between AF and BC.

Methods

We utilized the largest available genome-wide association study (GWAS) datasets for European individuals, including summary data for AF (N = 1,030,836) and BC (N = 247,173). Multiple approaches were employed to systematically investigate the genetic relationship between AF and BC from the perspectives of pleiotropy and causality.

Results

Global genetic analysis using LDSC and HDL revealed a genetic correlation between AF and BC (rg = 0.0435, P = 0.039). Mixer predicted genetic overlap between non-MHC regions of the two conditions (n = 125, rg = 0.05). Local genetic analyses using LAVA and GWAS-PW identified 22 regions with potential genetic sharing. Cross-trait meta-analysis by CPASSOC identified one novel pleiotropic SNP and 14 pleiotropic SNPs, which were subsequently annotated. Eight of these SNPs passed Bayesian colocalization tests, including one novel pleiotropic SNP. Further fine-mapping analysis identified a set of causal SNPs for each significant SNP. TWAS analyses using JTI and FOCUS models jointly identified 10 pleiotropic genes. Phenome-wide association study (PheWAS) of novel pleiotropic SNPs identified two eQTLs (PELO, ITGA1). Gene-based PheWAS results showed strong associations with BMI, height, and educational attainment. PCGA methods combining GTEx V8 tissue data and single-cell RNA data identified 16 co-enriched tissue types (including cardiovascular, reproductive, and digestive systems) and 5 cell types (including macrophages and smooth muscle cells). Finally, univariable and multivariable bidirectional Mendelian randomization analyses excluded a causal relationship between AF and BC.

Conclusion

This study systematically investigated the shared genetic overlap between AF and BC. Several pleiotropic SNPs and genes were identified, and co-enriched tissue and cell types were revealed. The findings highlight common mechanisms from a genetic perspective rather than a causal relationship. This study provides new insights into the AF-BC association and suggests potential experimental targets and directions for future research. Additionally, the results underscore the importance of monitoring the potential risk of one disease in patients diagnosed with the other.

Myeloid cell path to malignancy: insights into liver cancer

Clinically approved treatments for advanced liver cancer often lack potency because of the heterogeneous characteristics of hepatocellular carcinoma (HCC). This complexity is largely driven by context-dependent inflammatory responses brought on by diverse etiologies, such as metabolic dysfunction-associated steatohepatitis (MASH), the genetic makeup of cancer cells, and the versatile adaptability of immune cells, such as myeloid cells. In this review, we discuss the evolutionary dynamics of the immune landscape, particularly that of liver-resident Kupffer cells (KCs), TREM2+, and SPP1+ macrophages with an active role during liver disease progression, which eventually fuels hepatocarcinogenesis. We highlight exploitable immunomodulatory avenues amenable to mitigate both the inherent pathological characteristics of liver cancers and the associated external factors that favor malignancy, paving a roadmap toward improving the management and therapeutic outcome for patients with HCC.

Characterizing macrophage diversity in colorectal malignancies through single-cell genomics

Colorectal cancer (CRC) is one of the most common malignant tumors of the digestive tract, with increasing incidence and mortality rates, posing a significant burden on human health. Its progression relies on various mechanisms, among which the tumor microenvironment and tumor-associated macrophages (TAMs) have garnered increasing attention. Macrophage infiltration in various solid tumors is associated with poor prognosis and is linked to chemotherapy resistance in many cancers. These significant biological behaviors depend on the heterogeneity of macrophages. Tumor-promoting TAMs comprise subpopulations characterized by distinct markers and unique transcriptional profiles, rendering them potential targets for anticancer therapies through either depletion or reprogramming from a pro-tumoral to an anti-tumoral state. Single-cell RNA sequencing technology has significantly enhanced our research resolution, breaking the traditional simplistic definitions of macrophage subtypes and deepening our understanding of the diversity within TAMs. However, a unified elucidation of the nomenclature and molecular characteristics associated with this diversity remains lacking. In this review, we assess the application of conventional macrophage polarization subtypes in colorectal malignancies and explore several unique subtypes defined from a single-cell omics perspective in recent years, categorizing them based on their potential functions.

Continuous replenishment of the dysfunctional CD8 T cell axis is associated with response to chemoimmunotherapy in advanced breast cancer

Chemotherapy combined with immune checkpoint blockade has shown clinical activity in breast cancer. Response, however, occurs in only a low proportion of patients. How the immune landscape of the tumor determines the immune and clinical responses to chemoimmunotherapy is not well understood. Here, using a combination of single-cell RNA sequencing (scRNA-seq) and single-cell T cell receptor sequencing (scTCR-seq), we profile 40 biopsies from 27 patients with metastatic triple-negative breast cancer (TNBC), receiving chemotherapy and anti-PD-L1 alone or in combination with anti-CD73, in a phase 2 randomized clinical trial. Our results show an enrichment of late-dysfunctional, clonally expanded CD8+ T cells in responder (R) patients. On treatment, R display an influx of newly emerging clonotypes, as well as expansion of the CD8+ precursors. Collectively, our data suggest that baseline clonal expansion could be a potential predictor of response and that both clonal reinvigoration of pre-existing tumor-reactive T cells and clonal replacement on-treatment are important for a protective response to chemoimmunotherapy.

MuCST: restoring and integrating heterogeneous morphology images and spatial transcriptomics data with contrastive learning

Spatially resolved transcriptomics (SRT) simultaneously measure spatial location, histology images, and transcriptional profiles of cells or regions in undissociated tissues. Integrative analysis of multi-modal SRT data holds immense potential for understanding biological mechanisms. Here, we present a flexible multi-modal contrastive learning for the integration of SRT data (MuCST), which joins denoising, heterogeneity elimination, and compatible feature learning. MuCST accurately identifies spatial domains and is applicable to diverse datasets platforms. Overall, MuCST provides an alternative for integrative analysis of multi-modal SRT data ( https://github.com/xkmaxidian/MuCST ).

Multi-omics and machine learning-driven CD8+ T cell heterogeneity score for head and neck squamous cell carcinoma

The heterogeneity of head and neck squamous cell carcinoma (HNSCC) poses a significant challenge to treatment, underscoring the urgent need for more precise and personalized therapeutic approaches. CD8+ T cells, integral components of the tumor immune microenvironment, have emerged as key targets for immunotherapy. Our research has established a correlation between a decrease in CD8+ T cell score and a poor clinical prognosis, highlighting the prognostic value of this biomarker. By analyzing the gene expression related to CD8+ T cells, we have differentiated HNSCC into cold and hot tumor subtypes, uncovering disparities in clinical prognosis and responses to immunotherapy. Utilizing eight machine learning methods, we identified the key gene OLR1. Single-cell analysis of HNSCC tissues and peripheral blood, along with spatial transcriptome analysis, revealed that OLR1 predominantly functions in macrophages, modulating the immune microenvironment of HNSCC. The expression level of OLR1 may serve as a predictive marker for immunotherapy responses. Moreover, drug sensitivity analysis and molecular docking studies have indicated that simvastatin and pazopanib are potential inhibitors of OLR1. These findings suggest that simvastatin and pazopanib could open up innovative potential therapeutic avenues for individuals with HNSCC.

Integrative spatial analysis reveals tumor heterogeneity and immune colony niche related to clinical outcomes in small cell lung cancer

Recent advances have shed light on the molecular heterogeneity of small cell lung cancer (SCLC), yet the spatial organizations and cellular interactions in tumor immune microenvironment remain to be elucidated. Here, we employ co-detection by indexing (CODEX) and multi-omics profiling to delineate the spatial landscape for 165 SCLC patients, generating 267 high-dimensional images encompassing over 9.3 million cells. Integrating CODEX and genomic data reveals a multi-positive tumor cell neighborhood within ASCL1+ (SCLC-A) subtype, characterized by high SLFN11 expression and associated with poor prognosis. We further develop a cell colony detection algorithm (ColonyMap) and reveal a spatially assembled immune niche consisting of antitumoral macrophages, CD8+ T cells and natural killer T cells (MT2) which highly correlates with superior survival and predicts improving immunotherapy response in an independent cohort. This study serves as a valuable resource to study SCLC spatial heterogeneity and offers insights into potential patient stratification and personalized treatments.

Distinct cellular mechanisms underlie chemotherapies and PD-L1 blockade combinations in triple-negative breast cancer

Combining immune checkpoint blockade (ICB) with chemotherapy shows promise for treating triple-negative breast cancer (TNBC), though the mechanisms remain incompletely understood. Here, we integrate published and new single-cell RNA sequencing (scRNA-seq) data to investigate the tumor immune microenvironment (TIME) in TNBC patients treated with paclitaxel (PTX), nab-paclitaxel (Nab-PTX), and their combinations with the anti-PD-L1 antibody atezolizumab (ATZ). Compared to ATZ plus PTX, ATZ plus Nab-PTX rewires TCF7+ stem-like effector memory CD8+ T cells (Tsem) and CD4+ T follicular helper (Tfh) cells. Nab-paclitaxel, unlike PTX, also reshapes the myeloid compartment, expanding mast cells and pro-inflammatory macrophages. Our analyses in human TNBC and murine models underscore the crucial role of mast cells in orchestrating anti-tumor immune responses, likely by promoting the recruitment and activation of T and B cells. In vivo experiments demonstrate that activating mast cells alongside PD-L1 blockade attenuates TNBC progression, suggesting mast cells as a promising adjunct for enhancing ICB therapy efficacy.

Tissue macrophages: origin, heterogenity, biological functions, diseases and therapeutic targets

Macrophages are immune cells belonging to the mononuclear phagocyte system. They play crucial roles in immune defense, surveillance, and homeostasis. This review systematically discusses the types of hematopoietic progenitors that give rise to macrophages, including primitive hematopoietic progenitors, erythro-myeloid progenitors, and hematopoietic stem cells. These progenitors have distinct genetic backgrounds and developmental processes. Accordingly, macrophages exhibit complex and diverse functions in the body, including phagocytosis and clearance of cellular debris, antigen presentation, and immune response, regulation of inflammation and cytokine production, tissue remodeling and repair, and multi-level regulatory signaling pathways/crosstalk involved in homeostasis and physiology. Besides, tumor-associated macrophages are a key component of the TME, exhibiting both anti-tumor and pro-tumor properties. Furthermore, the functional status of macrophages is closely linked to the development of various diseases, including cancer, autoimmune disorders, cardiovascular disease, neurodegenerative diseases, metabolic conditions, and trauma. Targeting macrophages has emerged as a promising therapeutic strategy in these contexts. Clinical trials of macrophage-based targeted drugs, macrophage-based immunotherapies, and nanoparticle-based therapy were comprehensively summarized. Potential challenges and future directions in targeting macrophages have also been discussed. Overall, our review highlights the significance of this versatile immune cell in human health and disease, which is expected to inform future research and clinical practice.

Unveiling the key mechanisms of FOLR2+ macrophage-mediated antitumor immunity in breast cancer using integrated single-cell RNA sequencing and bulk RNA sequencing

Breast cancer (BRCA) is a common malignant tumor, and its immune microenvironment plays a crucial role in disease progression. In this research, we utilized single-cell RNA sequencing and bulk RNA sequencing technologies, combined with in vivo and in vitro experiments, to thoroughly investigate the immunological functions and mechanisms of FOLR2+ macrophages in BRCA. Our findings demonstrate a significant enhancement in the interaction between FOLR2+ macrophages and CD8+ T cells within the tumor tissues of BRCA patients. FOLR2 is closely associated with T cell infiltration in the tumor microenvironment of BRCA patients, particularly with CD8+ T cells. By secreting CXCL9 and engaging with CXCR3, FOLR2+ macrophages can activate the functionality of CD8+ T cells, thereby promoting cancer cell apoptosis. Further animal experiments confirm that FOLR2+ macrophages activate CD8+ T cells through the CXCL9-CXCR3 axis, exhibiting an antitumor immunity effect in BRCA. FOLR2+ macrophages play a crucial role in antitumor immunity in BRCA through the CXCL9-CXCR3 axis.

Development and validation of prognostic and diagnostic models utilizing immune checkpoint-related genes in public datasets for clear cell renal cell carcinoma

Background

Clear cell renal cell carcinoma (ccRCC) is the most prevalent subtype of renal cell carcinoma, and immune checkpoint regulator-based immunotherapy has emerged as an effective treatment for advanced stages of the disease. However, the expression patterns, prognostic significance, and diagnostic value of immune checkpoint-related genes (ICRGs) in ccRCC remain underexplored. This study utilized large-scale ccRCC datasets from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and the International Cancer Genome Consortium (ICGC) to analyze ICRGs and develop a prognostic and diagnostic model, which was validated using quantitative PCR in clinical samples from ccRCC patients.

Methods

RNA-seq data and clinical information were retrieved from TCGA, ICGC, and GEO databases. Differentially expressed genes (DEGs) were identified, and immune checkpoint-related genes (DICRGs) were selected by intersecting DEGs with ICRGs, followed by validation in independent datasets. Univariate and multivariate Cox regression analyses were used to develop the prognostic model. Protein expression of key genes was validated through immunohistochemistry (IHC) using data from the Human Protein Atlas (HPA). qRT-PCR confirmed gene expression levels in ccRCC and normal kidney tissues. Diagnostic models were constructed using machine learning, and functional enrichment and immune infiltration analyses were performed.

Results

Fourteen DICRGs were identified, with four (EGFR, TRIB3, ZAP70, and CD4) showing prognostic significance in Cox analyses. IHC revealed high expression of these genes in ccRCC tissues, and qRT-PCR confirmed increased expression of EGFR, TRIB3, and CD4, while ZAP70 expression showed no significant change. A prognostic risk score was developed based on gene expression levels. Functional analysis identified enriched pathways related to organic anion transport and metabolism, while immune infiltration analysis revealed associations between ZAP70, CD4, and risk scores.

Conclusion

This study establishes a prognostic model for ccRCC based on four ICRGs, providing valuable insights into the molecular mechanisms underlying prognosis and diagnosis in ccRCC.

Characterization of SUSD3 as a novel prognostic biomarker and therapeutic target for breast cancer

BACKGROUND

Breast cancer (BC) remains a significant global health challenge, contributing substantially to cancer-related deaths worldwide. Its prevalence and associated death rates remain alarmingly high, highlighting the persistent public health burden. The objective of this study was to systematically examine the involvement of SUSD3 (Sushi Domain-Containing 3) in BC, highlighting its crucial role in the pathogenesis and progression of this disease.

METHODS

BC-related gene microarray data, along with corresponding clinicopathological information, were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Leveraging TIMER and HPA databases, we conducted comparative analyses to evaluate SUSD3 expression in BC. We then analyzed the association between SUSD3 and clinical traits, as well as the prognostic value of SUSD3. SUSD3-related differential expression genes (DEGs) were sent for analysis utilizing GO, KEGG, and GSEA. We utilized SUSD3 mRNA expression to assess immune cells' scores in BC tissues calculated by single-sample enrichment analyses based on "CIBERSORT" R package. Drug sensitivity analysis was used to screen potential drugs sensitive to SUSD3. R software was used for statistical analyses and graphical representation of the data.

RESULTS

Our findings confirmed a significant upregulation of SUSD3 expression in BC, which correlated with a favorable prognosis. Clinical correlation analysis further emphasized the strong association between SUSD3 expression and key clinical parameters like estrogen receptor (ER) status, progesterone receptor (PR) status, stage, and T classification in breast cancer. Univariate and multivariate Cox regression analyses showed that SUSD3 could be used as an independent prognostic factor for BC. Differentially expressed genes (DEGs) co-expressed with SUSD3 were significantly associated with various biological processes, such as the cell cycle, DNA replication, p53 signaling pathway, cancer-related pathways, and Wnt signaling pathway, as indicated by gene set enrichment analysis (GSEA). Furthermore, our analysis demonstrated that SUSD3 generally exhibited negative associations with immune modulators. Drug sensitivity analysis revealed positive correlations between SUSD3 and the efficacy of Fulvestrant, Raloxifene, and Fluphenazine.

CONCLUSION

The research emphasizes the significance of SUSD3 as a potential marker for BC, providing insights into the underlying molecular mechanisms implicated in tumorigenesis. SUSD3 holds promise in helping the classification of breast cancer pathological groups, predicting prognosis, and facilitating targeted therapy.

Vax-Innate: improving therapeutic cancer vaccines by modulating T cells and the tumour microenvironment

T cells have a critical role in mediating antitumour immunity. The success of immune checkpoint inhibitors (ICIs) for cancer treatment highlights how enhancing endogenous T cell responses can mediate tumour regression. However, mortality remains high for many cancers, especially in the metastatic setting. Based on advances in the genetic characterization of tumours and identification of tumour-specific antigens, individualized therapeutic cancer vaccines targeting mutated tumour antigens (neoantigens) are being developed to generate tumour-specific T cells for improved therapeutic responses. Early clinical trials using individualized neoantigen vaccines for patients with advanced disease had limited clinical efficacy despite demonstrated induction of T cell responses. Therefore, enhancing T cell activity by improving the magnitude, quality and breadth of T cell responses following vaccination is one current goal for improving outcome against metastatic tumours. Another major consideration is how T cells can be further optimized to function within the tumour microenvironment (TME). In this Perspective, we focus on neoantigen vaccines and propose a new approach, termed Vax-Innate, in which vaccination through intravenous delivery or in combination with tumour-targeting immune modulators may improve antitumour efficacy by simultaneously increasing the magnitude, quality and breadth of T cells while transforming the TME into a largely immunostimulatory environment for T cells.

Urolithin A inhibits breast cancer progression via activating TFEB-mediated mitophagy in tumor macrophages

INTRODUCTION

Urolithin A (UA) is a naturally occurring compound that is converted from ellagitannin-like precursors in pomegranates and nuts by intestinal flora. Previous studies have found that UA exerts tumor-suppressive effects through antitumor cell proliferation and promotion of memory T-cell expansion, but its role in tumor-associated macrophages remains unknown.

OBJECTIVES

Our study aims to reveal how UA affects tumor macrophages and tumor cells to inhibit breast cancer progression.

METHODS

Observe the effect of UA treatment on breast cancer progression though in vivo and in vitro experiments. Western blot and PCR assays were performed to discover that UA affects tumor macrophage autophagy and inflammation. Co-ip and Molecular docking were used to explore specific molecular mechanisms.

RESULTS

We observed that UA treatment could simultaneously inhibit harmful inflammatory factors, especially for InterleuKin-6 (IL-6) and tumor necrosis factor α (TNF-α), in both breast cancer cells and tumor-associated macrophages, thereby improving the tumor microenvironment and delaying tumor progression. Mechanistically, UA induced the key regulator of autophagy, transcription factor EB (TFEB), into the nucleus in a partially mTOR-dependent manner and inhibited the ubiquitination degradation of TFEB, which facilitated the clearance of damaged mitochondria via the mitophagy-lysosomal pathway in macrophages under tumor supernatant stress, and reduced the deleterious inflammatory factors induced by the release of nucleic acid from damaged mitochondria. Molecular docking and experimental studies suggest that UA block the recognition of TFEB by 1433 and induce TFEB nuclear localization. Notably, UA treatment demonstrated inhibitory effects on tumor progression in multiple breast cancer models.

CONCLUSION

Our study elucidated the anti-breast cancer effect of UA from the perspective of tumor-associated macrophages. Specifically, TFEB is a crucial downstream target in macrophages.

Extracellular matrix cancer-associated fibroblasts promote stromal fibrosis and immune exclusion in triple-negative breast cancer

The impact of high heterogeneity of cancer-associated fibroblasts (CAFs) on triple-negative breast cancer (TNBC) immunotherapy response has not been fully elucidated, restricting progress in precision immuno-oncology. We integrated single-cell transcriptomic data from 18 TNBC patients and analyzed fibroblast subpopulations. Extracellular matrix CAFs (ecmCAFs) were identified as a fibroblast subpopulation with distinct ECM-associated characteristics. The ecmCAFs were significantly enriched in TNBC patients with residual disease after neoadjuvant immunotherapy and contributed to a fibrotic tumor microenvironment and T-cell exclusion. Secreted phosphoprotein 1 (SPP1) positive macrophages (SPP1+ Mφs) were closely localized to ecmCAFs and produced more transforming growth factor beta (TGFB1), interleukin 1 beta (IL1B), and SPP1 under hypoxic conditions. SPP1+ Mφs were found to facilitate the differentiation of normal breast fibroblasts to ecmCAFs, thus promoting ECM remodeling and stromal fibrosis. Our work revealed the critical role of ecmCAFs in generating a desmoplastic architecture and driving immunosuppression in TNBC. © 2025 The Pathological Society of Great Britain and Ireland.

Integrated bioinformatics investigation and experimental validation reveals the clinical and biological significance of chromobox family in breast cancer

Chromobox (CBX) proteins are essential components of the Polycomb group and play pivotal roles in tumor onset, progression, and metastasis. However, the prognostic significance and functions of CBXs in the advancement of breast cancer (BC) have not been sufficiently investigated. A comprehensive analysis of the expression and prognostic relevance of CBX1-8 in BC was conducted comprehensively using The Cancer Genome Atlas (TCGA) and multiple databases. High mRNA expression of CBX2, CBX3, and CBX5 in BC patients was significantly associated with reduced overall survival (OS). Results from univariate and multivariate Cox regression analysis revealed that the mRNA expression level of CBX2 in BC patients served as an independent prognostic factor. In Luminal A and Luminal B BC subtypes, high expression of CBX2 correlated with unfavorable prognosis. Subsequent Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses indicated a strong association between CBX2 and the cell cycle as well as DNA replication processes. CCK-8 and EdU assays demonstrated that silencing CBX2 inhibited the proliferation of T47D and MCF7 cell lines. Moreover, the cell cycle assay indicated that CBX2 silencing led to cell cycle arrest, accompanied by a significant decrease in the levels of CDK4 and CyclinD1. Elevated CBX2 expression significantly correlated with the infiltration of T cells, B cells, macrophages, and dendritic cells in BC. Our findings could provide new perspectives for identifying potential prognostic markers within the CBX family in BC. Targeting CBX2 may present a promising approach to address endocrine resistance in BC therapy.

A Dual Stimuli-Responsive Nanoimmunomodulator for Antitumor Synergy of Macrophages and T Cells

Only a minority of patients benefit from current T-cell-focused adaptive immunotherapies, underscoring the need to engage innate immune cells, particularly macrophages, for multilayered tumor control. However, high-efficacy therapeutics capable of orchestrating multiple immune cells remain scarce. Herein, a dual stimuli-responsive nanoimmunomodulator (6EPP@si) that caters specifically to the tumor microenvironment (TME) is presented for the antitumor synergy of macrophages and T cells. Using the functional polymer-based carrier, we co-deliver the endoplasmic reticulum (ER)-localized photosensitizer 6E and small interfering RNA targeting CD47 (siCD47) into breast tumors. Within the acidic and high-glutathione TME, 6EPP@si undergoes self-lysosome escape and nanocleavage for precise, on-demand drug release. Consequently, siCD47 released into the cytoplasm enables potent CD47 silencing, while the ER-targeted photosensitizer 6E induces immunogenic cell death through reactive oxygen species-based ER stress, triggering the release of damage-associated molecular patterns, including calreticulin surface translocation. 6EPP@si enhances macrophage phagocytosis by modulating both antiphagocytic and prophagocytic signals and also promotes antigen presentation to activate T cells. In orthotopic breast tumor and spontaneous lung metastatic tumor models, this combined approach demonstrates robust antitumor effects and effective antimetastatic immunity, offering a meaningful strategy to simultaneously activate multiple immune cells for enhancing cancer immunotherapy.

Bone marrow breakout lesions act as key sites for tumor-immune cell diversification in multiple myeloma

The bone marrow microenvironment plays a crucial role in the development of multiple myeloma. As the disease progresses, malignant myeloma cells can evolve to survive outside the bone marrow. However, the processes underlying bone marrow independence and their consequences for immune control remain poorly understood. Here, we conducted single-cell and spatial multiomics analyses of bone marrow-confined intramedullary disease and paired breakout lesions that disrupt the cortical bone. These analyses revealed a distinct cellular microenvironment and architectural features of breakout lesions, characterized by extensive areas of malignant plasma cells interspersed with lesion-specific solitary natural killer and macrophage populations, as well as focal accumulations of immune cell agglomerates. Within these agglomerates, spatially confined T cell clones expanded alongside various immune cells, coinciding with the local genomic evolution of tumor cells. These analyses identify breakout lesions as a hotspot for tumor-immune cell interactions and diversification, representing a key event in myeloma pathogenesis.

Single-cell RNA sequencing reveals tumor heterogeneity in small cell neuroendocrine cervical carcinoma

Small cell neuroendocrine cervical carcinoma (SCNECC) is an aggressive gynecological malignancy with poor prognosis. The precision therapeutic strategies for SCNECC are severely limited by the complex tumor microenvironment. Here, we mapped the single-cell landscape of a total of six samples from matched SCNECC cancerous foci and normal adjacent cervical tissues. Through analysis of 68,455 high-quality cells, malignant epithelial cells were identified with increased neuroendocrine differentiation and reduced keratinization. Within four epithelial cell clusters, the key transcription factors ASCL1, NEUROD1, POU2F3, and YAP1 defined molecular subtypes. Transitional trajectory among subtypes characterized two distinct carcinogenesis pathways in SCNECC. The P-type SCNECC showed potentially enhanced immune infiltration over other subtypes. Intercellular communication analysis identified several immune checkpoints and differentially expressed signaling pathways among subtypes. Through western blotting, the TC-YIK cell line was identified as an N-type SCNECC cell with high expression of SLFN11 and mTOR. Based on immunohistochemical staining of malignant subtyping markers, a cohort of 66 SCNECC patients from our hospital were divided into five subtypes. We further combined YAP1 expression with other clinicopathological factors (Cox p < 0.05) to establish a prognostic nomogram. Overall, these findings provide clues for tumorigenesis, precision treatments and prognostic prediction in SCNECC.

Recent advancement in the spatial immuno-oncology

Recent advancements in spatial transcriptomics and spatial proteomics enabled the high-throughput profiling of single or multi-cell types and cell states with spatial information. They transformed our understanding of the higher-order architectures and paired cell-cell interactions within a tumor microenvironment (TME). Within less than a decade, this rapidly emerging field has discovered much crucial fundamental knowledge and significantly improved clinical diagnosis in the field of immuno-oncology. This review summarizes the conceptual frameworks to understand spatial omics data and highlights the updated knowledge of spatial immuno-oncology.

PEGylated Nanoliposomal Doxorubicin Conjugated with Specific TREM2 Peptides for Glioma-Targeting Therapy

PEGylated liposomes can deliver anti-cancer drugs to brain tumors, and achieve enhanced permeability and retention effects. Triggering receptor expressed on myeloid cells 2 (TREM2) is an excellent biomarker for precise therapy of glioma. The present study is aimed at designing PEGylated nanoliposomal doxorubicin (PLD) conjugated with peptides targeting TREM2 for glioma-targeting therapy. The specific peptides are designed with the Rosetta Peptiderive Protocol. Schrodinger's peptide-specific version of Glide is used for molecular docking. PLD modified with peptides (peptide-PLD) are engineered and prepared. Cell cycle, apoptosis, cell invasion and migration, cell viability, and colony-formation assays are performed to analyze glioma cell functions. The anti-tumor effects of peptide-PLD are validated in an intracranial U87-MG cells orthotopic glioma model. The targeting peptides HLRKLRKR and LRKLRLRL showed specific affinity for TREM2 and better cellular uptake in U87-MG cells. PLD with peptide modification demonstrated stable doxorubicin loading, small sizes (<60 nm), and enrichment in the mouse brain. Peptide-PLD treatment inhibited the Akt/GSK3β/β-catenin pathway, thereby inhibiting cell invasion and migration, and colony-forming ability in U87-MG cells. The peptide modification of PLD achieved better suppression of glioma development than PLD. Overall, TREM2-targeting peptides are successfully designed, and peptide-PLD served as a potent drug delivery carrier for glioma-targeting therapy.

Nanoparticles Modulating the Immune Microenvironment in Breast Cancer Treatment

Breast cancer remains a significant therapeutic challenge, with the immune microenvironment playing a crucial role in its progression and treatment response. This review investigates the potential of nanoparticles to modulate the immune microenvironment in breast cancer therapy. Initially, we discuss the composition and influence of the immune microenvironment on breast cancer, followed by current strategies targeting these components. We then provide strategies of nanoparticles for targeting immune cells such as macrophages, dendritic cells, and T-cells. The role of nanoparticles in enhancing immune checkpoint blockade (ICB) and their application in cancer vaccines is also examined. Additionally, we explore the synergistic effects of combining nanoparticles with conventional therapies. The review addresses the challenges in clinical translation, focusing on safety, biocompatibility, and toxicity. Finally, we outline future research directions and the potential advancements in nanoparticle-based immunotherapy, emphasizing their transformative impact on breast cancer treatment.