Tumor-Associated Macrophages in Tumor Immunity

Nanotherapeutic strategies exploiting biological traits of cancer stem cells

Cancer stem cells (CSCs) represent a distinct subpopulation of cancer cells that orchestrate cancer initiation, progression, metastasis, and therapeutic resistance. Despite advances in conventional therapies, the persistence of CSCs remains a major obstacle to achieving cancer eradication. Nanomedicine-based approaches have emerged for precise CSC targeting and elimination, offering unique advantages in overcoming the limitations of traditional treatments. This review systematically analyzes recent developments in nanomedicine for CSC-targeted therapy, emphasizing innovative nanomaterial designs addressing CSC-specific challenges. We first provide a detailed examination of CSC biology, focusing on their surface markers, signaling networks, microenvironmental interactions, and metabolic signatures. On this basis, we critically evaluate cutting-edge nanomaterial engineering designed to exploit these CSC traits, including stimuli-responsive nanodrugs, nanocarriers for drug delivery, and multifunctional nanoplatforms capable of generating localized hyperthermia or reactive oxygen species. These sophisticated nanotherapeutic approaches enhance selectivity and efficacy in CSC elimination, potentially circumventing drug resistance and cancer recurrence. Finally, we present an in-depth analysis of current challenges in translating nanomedicine-based CSC-targeted therapies from bench to bedside, offering critical insights into future research directions and clinical implementation. This review aims to provide a comprehensive framework for understanding the intersection of nanomedicine and CSC biology, contributing to more effective cancer treatment modalities.

The role of RGS12 in tissue repair and human diseases

Regulator of G protein signaling 12 (RGS12) belongs to the superfamily of RGS proteins defined by a conserved RGS domain that canonically binds and deactivates heterotrimeric G-proteins. As the largest family member, RGS12 is widely expressed in many cells and tissues. In the past few decades, it has been found that RGS12 affects the activity of various cells in the human body, participates in many physiological and pathological processes, and plays an important role in the pathogenesis of many diseases. Here, we set out to comprehensively review the role of RGS12 in human diseases and its mechanisms, highlighting the possibility of RGS12 as a therapeutic target for the treatment of human diseases.

Necrostatin-1 attenuates oral squamous cell carcinoma by modulating tumour immune response in mice

BACKGROUND

Necroptosis has been shown to play an important role in various pathologies, including pancreatic cancer (PDAC). However, its role in the progression of oral cancer (OSCC) remains unclear.

OBJECTIVES

To determine the expression of key necroptosis pathway markers in an OSCC mouse model and evaluate the therapeutic effect of a necroptosis inhibitor on the progression of OSCC.

METHODS AND RESULTS

4-NQO-induced OSCC in mice resembles very closely to human OSCC. The expression of RIPK-1, RIPK-3, MLKL and their respective phosphorylation was increased in OSCC tissues of cancer-bearing mice. In the analysis of the necroptosis pathway in human OSCC with the TCGA database, we found similar overexpression of RIPK-1 in human cancer, which correlated with the severity of cancer in terms of different cancer grades and stages. Pharmacological blockade of necroptosis with necrostatin-1 (NEC-1) reduced the progression and development of OSCC, characterized by reduced number and severity of tumour lesions, improved histology with reduced hyperplasia, dysplasia and invasive carcinoma. Immune profiling of blood, spleen and tumour tissues demonstrated suppressed expression of MDSCs (CD11b+Gr-1+) and M2-macrophages (CD11b+F4/80+CD206+), while M1-macrophages (CD11b+F4/80+MHCII+) were elevated in the treatment group. The ratio of M2/M1 was reduced in the treated group, suggesting the promotion of anti-tumour immune response. Expression of Arg-1, YM1/2, IL-10 and TGF-β was reduced in tumour tissues in the treated group.

CONCLUSION

In summary, blocking the necroptosis pathway alters the tumour microenvironment (TME) and inhibits the progression of OSCC. Targeting necroptosis could be an effective therapy for treating OSCC in a clinical setup.

Progress of IL-10 and liver metastasis

Liver metastasis can occur in a wide range of cancers and have a significant impact on patient survival and prognosis. Once liver metastasis occurs, patients often lose the opportunity for surgery, and although a small percentage of patients can undergo hepatic resection to prolong survival, the benefit is not great. There were also many factors affecting liver metastasis, including reprogramming of the primary tumor metabolism, disturbances in the immune microenvironment and immune cells, alterations in the gut microbiota, and epigenetic changes. Interleukin-10 (IL-10) has a dual role as a cytokine that has been found in recent years to be pro-inflammatory as well as pro-liver metastasis. IL-10 exerts pro-metastatic effects mainly by regulating the polarization of tumor macrophages in the tumor microenvironment, especially by promoting the polarization of M2 macrophages. However, the role of IL-10 in tumorigenesis and progression remains controversial and the molecular mechanism involved in promoting liver metastasis is currently unclear. In view of the increasing role of IL-10 in promoting liver metastasis, this review summarizes the role of IL-10 in liver metastasis of colorectal cancer, breast cancer and other tumors in recent years, and provides ideas for subsequent clinical practice and basic research.

MiRNA affects the advancement of breast cancer by modulating the immune system's response

Breast cancer (BC), which is the most common tumor in women, has greatly endangered women's lives and health. Currently, patients with BC receive comprehensive treatments, including surgery, chemotherapy, radiotherapy, endocrine therapy, and targeted therapy. According to the latest research, the development of BC is closely related to the inflammatory immune response, and the immunogenicity of BC has steadily been recognized. As such, immunotherapy is one of the promising and anticipated forms of treatment for BC. The potential values of miRNA in the diagnosis and prognosis of BC have been established, and aberrant expression of associated miRNA can either facilitate or inhibit progression of BC. In the tumor immune microenvironment (TME), miRNAs are considered to be an essential molecular mechanism by which tumor cells interact with immunocytes and immunologic factors. Aberrant expression of miRNAs results in reprogramming of tumor cells actively, which may suppress the generation and activation of immunocytes and immunologic factors, avoid tumor cells apoptosis, and ultimately result in uncontrolled proliferation and deterioration. Therefore, through activating and regulating the immunocytes related to tumors and associated immunologic factors, miRNA can contribute to the advancement of BC. In this review, we assessed the function of miRNA and associated immune system components in regulating the advancement of BC, as well as the potential and viability of using miRNA in immunotherapy for BC.

Overexpression of FMOD in Thyroid Carcinoma Triggers M1-Like Tumor-Associated Macrophage Polarization by Targeting Rap1B

Thyroid carcinoma, with limited efficacy of current treatment, influences the lives and health of many people. It is important to explore potential therapeutic targets for thyroid carcinoma. Fibromodulin (FMOD) has been indicated to be connected with the progression of different kinds of tumors, with unknown functions in thyroid carcinoma. In this study, the potential candidate therapeutic targets for thyroid carcinoma were identified by bioinformatics methods, and FMOD was screened out for verification. Cell counting kit-8, wound healing, transwell, and flow cytometry assays were conducted to determine the role of FMOD overexpression in cell viability, migration, invasion, and apoptotic rate of thyroid carcinoma cells, respectively. Subcutaneous tumor growth was monitored in nude mice. Tumor-associated macrophages (TAMs) were co-cultured with thyroid carcinoma cells, and the surface marker of M1-like TAMs, CD80, was identified by flow cytometry. Ras-association proximate 1B (Rap1B), the downstream target of FMOD, was predicted by bioinformatic techniques and validated by Rap1B overexpression rescue. FMOD was identified as a tumor suppressor gene in thyroid carcinoma through bioinformatic techniques. FMOD overexpression inhibited cell viability, migration, and invasion and stimulated apoptosis of thyroid carcinoma cells. In vivo, FMOD upregulation could suppress the growth of solid tumors. Moreover, FMOD overexpression in thyroid carcinoma cells promoted M1-like TAM polarization. FMOD downregulated Rap1B expression in thyroid carcinoma cells, and Rap1B overexpression rescue reversed the impact of FMOD on tumor progression and TAM polarization. In conclusion, FMOD exhibited an inhibitory effect on thyroid carcinoma by stimulating M1-like TAM polarization via targeting Rap1B.

Macrophage Membrane-Coated Nanomedicine Enhances Cancer Immunotherapy by Activating Macrophages and T Cells

Cancer immunotherapy has transformed malignancy treatment, but the tumor microenvironment (TME) presents significant obstacles. PD-1 blockade therapy, while widely used, faces issues such as resistance, adverse events, and limited predictive biomarkers. Therefore, novel therapeutic strategies are needed to enhance their efficacy and safety. Tumor-associated macrophages (TAMs), often exhibiting an anti-inflammatory M2 phenotype, contribute to poor prognoses and treatment resistance. Targeting TAMs to repolarize them to a pro-inflammatory M1 state can alleviate immunosuppression and enhance T cell-mediated antitumor responses. TMP195, a class IIa histone deacetylase inhibitor, has shown potential in reprogramming TAMs and synergizing with anti-PD-1 antibodies, although clinical application challenges exist. This study aimed to enhance the PD-1 blockade immunotherapy effectiveness by activating tumor-killing macrophages and T cells using biomimetic nanomedicines. A novel macrophage cell membrane-coated PLGA nanoparticle loaded with small molecule inhibitor, TMP195 (M1@PLGA-PEG-TMP195), was designed, prepared, and characterized. This macrophage membrane-coated PLGA nanoparticle delivery system had good drug loading and cancer cell targeting ability. This approach repolarized TAMs to M1 phenotypes and, combined with PD-1 inhibitors, achieved synergistic cancer treatment effects, improving therapeutic efficacy and inhibiting breast cancer growth and metastasis.

The immunosuppressive role of VSIG4 in colorectal cancer and its interaction with the tumor microenvironment

BACKGROUND

The tumor microenvironment in colorectal cancer (CRC) significantly influences disease progression and immune responses, particularly the role of macrophages in regulating immune evasion requires further investigation.

METHODS

This study integrated data from the TCGA-COAD dataset with the GEO database, along with single-cell RNA sequencing data, to systematically analyze key genes in colorectal cancer. R software was utilized for data normalization and differential analysis, with criteria set at ∣log2FoldChange ∣ > 1 and adjusted p-value < 0.05 for gene selection. The Seurat package was employed for clustering single-cell data, while the "Monocle2" algorithm was used to perform pseudo-time analysis on the differentiation trajectory of macrophages. Additionally, non-negative matrix factorization (NMF) was applied for subtype classification of CRC patients, and various machine learning algorithms (such as LASSO and random forest models) were utilized to identify key pathogenic genes. Finally, PCR was employed to validate the expression of these key genes, and immune analysis software was used to assess their impact on immune cells, alongside pathway enrichment analysis.

RESULTS

Through the integration of multi-omics data, we identified significant differential expression of VSIG4, CYBBC3AR1, and FCGR1A in CRC patients. LASSO and random forest models selected these three genes as critical pathogenic factors for CRC, with AUC values exceeding 0.8 across multiple machine learning models, demonstrating their high diagnostic efficacy. PCR validation further supported the differential expression of VSIG4 and other genes in CRC. Single-cell transcriptomic analysis revealed that VSIG4 was highly enriched in specific macrophage subpopulations and significantly influenced the tumor microenvironment by regulating CD8 + T cell immune exhaustion. Pseudo-time analysis indicated that the differentiation trajectory of macrophages during tumor progression was closely associated with VSIG4 expression. Additionally, cell communication analysis. highlighted the important role of VSIG4 in the interactions between macrophages and endothelial cells. Pathway enrichment analysis demonstrated that VSIG4 expression was closely linked to the regulation of the JAK-STAT pathway and metabolic pathways such as the TCA cycle.

CONCLUSION

This study provides the first evidence that VSIG4, CYBBC3AR1, and FCGR1A play critical roles in the immune microenvironment of colorectal cancer, particularly emphasizing the immunoregulatory function of VSIG4 in macrophage activity and CD8 + T cell immune exhaustion. PCR validation further confirmed the differential expression of these genes. These findings offer new insights into the molecular mechanisms of CRC and provide a potential theoretical basis for targeting VSIG4 in immunotherapy.

Targeting pyroptosis for cancer immunotherapy: mechanistic insights and clinical perspectives

Pyroptosis is a distinct form of programmed cell death characterized by the rupture of the cell membrane and robust inflammatory responses. Increasing evidence suggests that pyroptosis significantly affects the tumor microenvironment and antitumor immunity by releasing damage-associated molecular patterns (DAMPs) and pro-inflammatory mediators, thereby establishing it as a pivotal target in cancer immunotherapy. This review thoroughly explores the molecular mechanisms underlying pyroptosis, with a particular focus on inflammasome activation and the gasdermin family of proteins (GSDMs). It examines the role of pyroptotic cell death in reshaping the tumor immune microenvironment (TIME) involving both tumor and immune cells, and discusses recent advancements in targeting pyroptotic pathways through therapeutic strategies such as small molecule modulators, engineered nanocarriers, and combinatory treatments with immune checkpoint inhibitors. We also review recent advances and future directions in targeting pyroptosis to enhance tumor immunotherapy with immune checkpoint inhibitors, adoptive cell therapy, and tumor vaccines. This study suggested that targeting pyroptosis offers a promising avenue to amplify antitumor immune responses and surmount resistance to existing immunotherapies, potentially leading to more efficacious cancer treatments.

A coagulation-related long non-coding RNA signature to predict prognosis and immune features of breast cancer

Breast cancer (BC) remains one of the most common malignancies among women worldwide, with persistently poor prognosis despite advancements in diagnostics and therapies. Long non-coding RNAs (lncRNAs) and coagulation-related genes (CRGs) are increasingly recognized for their roles in prognosis and immune modulation. Using transcriptomic data from 1,045 BC patients in TCGA, we identified CRG-associated lncRNAs via coexpression analysis (Pearson |R|> 0.4, p < 0.001) and constructed a prognostic model through univariate Cox analysis, LASSO regression with tenfold cross-validation (λ = 0.05), and multivariate Cox analysis. The model stratified patients into high- and low-risk groups with distinct overall survival (HR = 3.21, p < 0.001) and demonstrated robust predictive accuracy (AUC = 0.795 at 1 year). Functional enrichment revealed immune-related pathways (e.g., cytokine signaling, PD-L1 regulation), and high-risk patients exhibited elevated tumor mutational burden (TMB) and PD-L1 expression, suggesting enhanced immunotherapy responsiveness. Drug sensitivity analysis identified 5 targeted agents (e.g., BIBW2992) with differential efficacy between risk groups. This CRG-lncRNA signature provides a novel tool for prognosis prediction and personalized immunotherapy in BC, illuminating crosstalk between coagulation and immune pathways.

Tumor microenvironment modulation innovates combinative cancer therapy via a versatile graphene oxide nanosystem

The tumor microenvironment (TME) emerges as a unique challenge to oncotherapy due to its intricate ecosystem containing diverse cell types, extracellular matrix, secreted factors, and neovascularization, which furnish tumor growth, progression, invasion, and metastasis. Graphene oxide (GO)-based materials have garnered increasing attention in cancer therapy owing to their vast specific surface area, flexible lamellar structure, and electronic-photonic properties. Recently, interactions of GO with the TME have been broadly investigated, including trapping biomolecules, catalysis, cancer stem cell targeting, immunoreactions, etc., which inspires combinative therapeutic strategies to overcome TME obstacles. Herein, we summarize TME features, GO modulating various dimensions of the TME, and a TME-triggerable drug delivery system and highlight innovation and merits in combinative cancer therapy based on TME modulation. This review aims to offer researchers deeper insights into the interactions between versatile GO nanomaterials and the TME, facilitating the development of rational and reliable GO-based nanomedicines for advanced oncotherapy.

Multifaceted roles of OCT4 in tumor microenvironment: biology and therapeutic implications

OCT4 (Octamer-binding transcription factor 4, encoded by the POU5F1 gene) is a master transcription factor for maintaining the self-renewal and pluripotency of pluripotent stem cells, as well as a pioneer factor regulating epigenetics-driven cell reprogramming and cell fate conversion. It is also detected in a variety of cancer tissues and particularly in a small subpopulation of cancer cells known as cancer stem cells (CSCs). Accumulating evidence has revealed that CSCs are a dynamic population, exhibiting shift between multipotency and differentiation states, or quiescence and proliferation states. Such cellular plasticity of CSCs is profoundly influenced by dynamic interplay between CSCs and the tumor microenvironment (TME). Here, we review recent evidence showing that OCT4 expressed in CSCs plays a multifaceted role in shaping the TME by interacting with the cellular TME components, including cancer-associated fibroblasts, tumor endothelial cells, tumor-infiltrating immune cells, as well as the non-cellular TME components, such as extracellular matrix (ECM), metabolites, soluble factors (e.g., growth factors, cytokines and chemokines), and intra-tumoral microbiota. Together, OCT4 regulates crucial processes encompassing ECM remodeling, epithelial-mesenchymal transition, metabolic reprogramming, angiogenesis, and immune responses. The complex and bidirectional interactions between OCT4-expressing CSCs and the TME create a supportive niche for tumor growth, invasion, and resistance to therapy. Better understanding OCT4's roles in such interactions can provide deeper insights into potential therapeutic strategies and targets for disrupting the supportive environment of tumors. The emerging therapies targeting OCT4 in CSCs might hold promise to resensitize therapeutic-resistant cancer cells, and to eradicate all cancer cells when combined with other therapies targeting the bulk of differentiated cancer cells as well as the TME.

Metabolism profiles of tannins in Phyllanthus emblica L. and its immunotherapeutic potential against hepatocellular carcinoma by re-educating tumor microenvironment

PURPOSE

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide. Tumor-associated macrophages (TAMs) are key components of the immunosuppressive tumor microenvironment and represent significant obstacles to effective immunotherapy. Phyllanthus emblica L. (PE), a medicinal plant traditionally used in Tibet, has shown therapeutic promise. This study investigates the effects of the tannin fraction of PE (PE-TF) on HCC and its ability to modulate the tumor immunosuppressive microenvironment.

METHODS

We evaluated the antitumor efficacy of PE-TF using H22 xenografts and Hepa1-6 orthotopic mouse models. Transcriptomic analysis was performed to identify molecular targets underlying PE-TF suppression of HCC growth. Additionally, UPLC-MS/MS analysis identified the prototypic and metabolic components of PE-TF present in serum, tumor tissues, and adjacent normal liver tissues in the orthotopic HCC model.

RESULTS

PE-TF significantly suppressed tumor growth in both subcutaneous and orthotopic HCC models and promoted reprogramming of TAMs toward an antitumor M1 phenotype in vivo. Furthermore, PE-TF counteracted the protumoral effects mediated by bone marrow-derived macrophages (BMDMs) exposed to Hepa1-6-derived conditioned medium (HCM). Although TBH promoted macrophage M2 polarization, the reactive oxygen species (ROS)-scavenging activity of PE-TF effectively inhibited this process. Modulation of the tumor microenvironment by PE-TF-enhanced CD8+T cell infiltration and bolstered their antitumor response, as evidenced by increased transcription of perforin, IFN-γ, and IL-2. Transcriptomic analysis further revealed that T-cell receptor and cytotoxic T-cell signaling pathways are critical mediators of PE-TF' therapeutic effects. Moreover, we preliminarily characterized 79 components across serum, liver, and tumor tissues, and identified metabolic pathways for PE-TF ingredients-including methylation and glycosylation modifications of tumor-enriched constituents. Notably, seven components, such as corilagin and urolithin D, are hypothesized to possess immunomodulatory properties.

CONCLUSION

Our findings underscore the potential of PE-TF as an adjuvant immunotherapy for HCC. By scavenging ROS, PE-TF reverses the immunosuppressive M2-TAM phenotype and remodels the tumor microenvironment, thereby enhancing antitumor immunity. Additionally, integrating chemical and metabolic profiling offers a promising strategy for refining candidate selection in future drug discovery endeavors.

The roles of algal polysaccharides in modulating tumor immune microenvironment

BACKGROUND

Polysaccharides from algae provide a range of biology and health benefits. Lately, there has been a significant interest in how algal polysaccharides affect the immune microenvironment around tumors.

PURPOSE

To elucidate the subtle interactions between algal polysaccharides and the tumor immune microenvironment to further understand the medicinal potential of algal polysaccharides.

STUDY DESIGN

To give a summary of the sources, bioactivities and characteristics of the tumor immune microenvironment of algal polysaccharides, and to analyze alteration of the immunological milieu surrounding tumors by algal polysaccharides and their potential as immunomodulators of chemotherapeutic agents.

METHODS

Search popular academic search engines using selected keywords for articles ending before September 2024 using selected keywords Google Scholar, PubMed, ScienceDirect, Scopus, Web of Science, Springer, and official websites.

RESULTS

Algal polysaccharides can fight tumors by changing how immune cells work and affecting inflammation in different ways. Moreover, algal polysaccharides have shown promise in mitigating the adverse effects associated with conventional cancer treatments, such as chemotherapy. Algal polysaccharides, through their immunomodulatory effects, can alleviate some of these side effects, leading to an enhanced overall treatment outcome.

CONCLUSION

As research continues to uncover the underlying mechanisms of their antitumor effects, algal polysaccharides are poised to become a vital component in the development of novel cancer treatments, providing new hope for patients and advancing the field of oncology.

Single-cell sequencing reveals PHLDA1-positive smooth muscle cells promote local invasion in head and neck squamous cell carcinoma

BACKGROUND

Smooth muscle cells within the tumor microenvironment play a crucial role in cancer progression. However, their involvement in the local invasion of head and neck squamous cell carcinoma remains poorly understood. In this research, we aim to investigate the role of smooth muscle cells-mediated cell interactions in facilitating the local invasion of head and neck squamous cell carcinoma.

METHODS

Single-cell sequencing data from the public databases GSE164690 and GSE181919 were utilized to identify a specific smooth muscle cells cluster. Smooth muscle cells were isolated from tumor microenvironment of head and neck squamous cell carcinoma. PHLDA1 expression in smooth muscle cells was assessed through immunofluorescence staining. The role of THBS1 was investigated through in vitro studies.

RESULTS

PHLDA1-positive smooth muscle cells were significantly enriched in head and neck squamous cell carcinoma. PHLDA1 promoted the expression of THBS1 in smooth muscle cells. In vitro, THBS1 facilitated head and neck squamous cell carcinoma migration and invasion through SDC1 receptor.

CONCLUSION

PHLDA1-positive smooth muscle cells play a critical role in head and neck squamous cell carcinoma invasion through THBS1. Targeting PHLDA1-positive smooth muscle cells or THBS1 may offer a promising therapeutic approach for head and neck squamous cell carcinoma treatment.

Single cell analysis reveals that SPP1+ macrophages enhance tumor progression by triggering fibroblast extracellular vesicles

Patients with liver metastatic colorectal cancer (mCRC) have a poor prognosis and are the leading cause of death in colorectal cancer (CRC) patients, but the mechanisms associated with CRC metastasis have not been fully elucidated. In this study, we obtained data from the Gene Expression Omnibus database and characterized the single-cell profiles of CRC, mCRC and healthy samples at single-cell resolution, and explored the cells that influence CRC metastasis. We find that AQP1+ CRC identified as highly malignant tumor cells exhibited proliferative and metastatic characteristics. Immunosuppressive properties are present in the tumor microenvironment (TME), while NOTCH3+ Fib is identified to play a facilitating role in the metastatic colonization of CRC. Importantly, we reveal that tumor-associated macrophages (TAM) characterized by SPP1-specific high expression may be involved in TME remodeling through intercellular communication. Specifically, SPP1+ TAM mediates the generation of Fib-derived extracellular vesicle through the APOE-LRP1 axis, which in turn delivers tumor growth-promoting factors in the TME. This study deepens the understanding of the mechanism of TME in mCRC and lays the scientific foundation for the development of therapeutic regimens for mCRC patients.

Beyond the brain: Reelin's emerging role in cancer pathways

The glycoprotein Reelin is essential for neuronal migration during embryonic development and is involved in various cellular processes. It interacts with specific lipoprotein receptors to regulate neuronal migration and synaptic plasticity. Recent research has expanded our understanding of Reelin's functions, revealing its involvement in processes such as cell proliferation, activation, migration, platelet aggregation, and vascular development. Reelin's influence extends beyond neurodevelopment, with abnormal expression observed in several cancer types. This suggests a potential connection between Reelin dysregulation and tumor formation. Altered Reelin levels correlate with increased tumor aggressiveness, metastatic potential, and poor patient outcomes. In cancer, Reelin affects key cellular processes including proliferation, migration, and invasion. Evidence indicates that Reelin modulates important signaling pathways like PI3K/Akt and MAPK, contributing to the development of cancer hallmarks. Its interactions with integrins and matrix metalloproteinases imply a role in shaping the tumor microenvironment, thereby influencing cancer progression. These findings highlight Reelin's dual significance in neurodevelopment and cancer biology. Further investigation into Reelin's complex functions could lead to new diagnostic tools and therapeutic approaches, potentially advancing cancer treatment through targeted research on its signaling mechanisms. This review provides a condensed overview of Reelin's multifaceted roles in both neurodevelopment and cancer.

Claudin18.2-positive gastric cancer-specific changes in neoadjuvant chemotherapy-driven immunosuppressive tumor microenvironment

BACKGROUND

Claudin 18 isoform 2 (CLDN18.2) is a potential therapeutic target in gastric cancer (GC). However, combining chemotherapy with anti-CLDN18.2 antibodies has shown limited efficacy in CLDN18.2-positive GC, and chemotherapy-induced changes in the tumor microenvironment (TME) remain unclear.

METHODS

This study analyzed 37 GC samples, including 11 CLDN18.2-positive cases, using single-cell RNA sequencing and multiplex immunofluorescence to assess chemotherapy-driven TME changes in CLDN18.2-positive GC.

RESULTS

In chemotherapy-treated CLDN18.2-positive GC, cytotoxic natural killer (NK) cells displayed antibody-dependent cytotoxicity (ADCC)-related genes at lower levels than in untreated CLDN18.2-positive GC, while regulatory T cells (Tregs) and tumor-associated macrophages (TAMs) showed TGFB1 expression at higher levels. Additionally, NK cells, Tregs, and TAMs were more abundant in chemotherapy-treated than untreated CLDN18.2-positive GC. These chemotherapy-induced changes were absent in CLDN18.2-negative GC. Cell-cell interaction analysis identified unique interactions in chemotherapy-treated CLDN18.2-positive GC, including CCL5-CCR5 signaling between cytotoxic NK cells (Sender) and effector Tregs (Receptor) and TGFB1-TGFBR signaling between effector Tregs (Sender) and TAMs (Receptor). Cytotoxic NK cells expressed CCL5 at higher levels, CCR5-positive Tregs were more prevalent, and TAMs exhibited higher TGF-β receptor signature scores in chemotherapy-treated than untreated CLDN18.2-positive GC.

CONCLUSIONS

Our findings indicate that chemotherapy can drive immunosuppressive TME modifications specific to CLDN18.2-positive GC.

M2 macrophages-derived exosomal MDH1 drives lung adenocarcinoma progression via the Hippo/YAP signaling

BACKGROUND

Exosomes are released by most cell types, including tumor-associated macrophages (TAMs), transfer diverse macromolecules and participate in intercellular communication in cancer. However, whether M2-polarized TAMs (M2-TAMs)-derived exosomes (M2-exos) transmit the oncogenic protein malate dehydrogenase 1 (MDH1) to reprogram lung adenocarcinoma (LUAD) cancer cells is unknown.

METHODS

THP-1-differentiated macrophages were co-cultured with A549 cells to generate TAMs (M0-TAMs and M2-TAMs). Exosomes (M0-exos and M2-exos) were isolated from the co-culture supernatant and characterized. Xenograft studies were used to explore the effect of M2-exos-derived MDH1 on tumor growth. Expression analysis was performed by quantitative PCR, immunoblot and immunohistochemistry (IHC). Cell phenotype changes were detected by CCK-8, EdU, colony formation, wound-healing and transwell assays.

RESULTS

Bioinformatics analyses confirmed that MDH1 was overexpressed in human LUAD and high MDH1 expression was associated with poor prognosis. MDH1 depletion resulted in the in vitro suppression of LUAD cell growth, migration and invasiveness. M2-exos contained and transferred MDH1 into LUAD cells to upregulate MDH1 level in these cells. M2-exos-derived MDH1 enhanced the growth of A549 xenograft tumors in vivo and activated the Hippo/YAP pathway in vitro. Furthermore, Yes-associated protein (YAP) depletion could abrogate M2-exos-induced enhancements in these malignant phenotypes of A549 and HCC827 LUAD cells.

CONCLUSION

These findings demonstrate that exosomal MDH1 derived from M2-TAMs enhance LUAD cell growth and metastasis by activating the Hippo/YAP signaling, uncovering a novel exosomal mechanism of crosstalk between tumor microenvironment and LUAD cells.

Mechanisms of breast cancer metastasis: the role of extracellular matrix

The components of the extracellular matrix (ECM) are dynamic, and they mediate mechanical signals that modulate cellular behaviors. Disruption of the ECM can induce the migration and invasion of cancer cells via specific signaling pathways and cytokines. Metastasis is a leading cause of high mortality in malignancies, and early intervention can improve survival rates. However, breast cancer is frequently diagnosed subsequent to metastasis, resulting in poor prognosis and distant metastasis poses substantial hurdles in therapy. In breast cancer, there is notable tissue remodeling of ECM proteins, with several identified as essential components for metastasis. Moreover, specific ECM molecules, receptors, enzymes, and various signaling pathways play crucial roles in breast cancer metastasis, drug treatment, and resistance. The in-depth consideration of these elements could provide potential therapeutic targets to enhance the survival rates and quality of life for breast cancer patients. This review explores the mechanisms by which alterations in the ECM contribute to breast cancer metastasis and discusses current clinical applications targeting ECM in breast cancer treatment, offering valuable perspectives for future ECM-based therapies.

Decoding the role of lipid metabolism in NSCLC: From macrophage subtype identification to prognostic model development

Lipid metabolism plays a pivotal role in shaping the tumor microenvironment, particularly by influencing macrophage function. This study aimed to identify lipid-associated macrophage (LAM) marker genes involved in the onset and progression of non-small cell lung cancer (NSCLC) through integrated single-cell RNA sequencing (scRNA-seq) and bulk RNA sequencing (bulk RNA-seq) analyses. Mutation and RNA-seq data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were analyzed to explore the relationship between lipid metabolism pathways and NSCLC progression. scRNA-seq analysis revealed macrophage subtypes closely associated with lipid metabolism, with three key marker genes-S100A10, HLA-DMB, and CTSL-identified as predictive factors for patient prognosis. A prognostic risk scoring model was constructed and validated using survival analysis and ROC curves, demonstrating high accuracy in stratifying NSCLC patients by risk. Further in vivo experiments using subcutaneous tumor xenografts and lung metastasis models showed that S100A10 and CTSL promoted tumor growth and metastasis, while HLA-DMB inhibited these processes. Immune infiltration analysis highlighted the immunological relevance of the identified marker genes, providing insights into their functional roles. This study underscores the critical influence of LAMs in NSCLC progression and highlights a robust prognostic model that offers potential therapeutic targets for improving patient outcomes.

Comprehensive pan-cancer analysis identified SLC16A3 as a potential prognostic and diagnostic biomarker

SLC16A3, belonging to the SLC16 gene family, is involved in the transportation of monocarboxylate. SLC16A family members play important roles in tumorigenesis, nonetheless, the specific involvement of SLC16A3 in tumor prognosis and diagnosis in human cancers remains unelucidated. This study dealt with the exploration of SLC16A3 expression in human pan-cancer and its significance regarding disease prognosis. For this investigation, the mRNA expression data of SLC16A3 were acquired from the TCGA and the GTEx datasets. The Kaplan-Meier plots, univariate Cox regression, and the ROC curve were employed for assessing the prognostic and diagnostic significance of SLC16A3 in pan-cancer. Furthermore, the cBioPortal database was used to analyze the SLC16A3 genomic alterations. Moreover, the association of the infiltration of immune cells and immune checkpoint genes with SLC16A3 was analyzed by the TIMER database. Gene Ontology and KEGG pathway analysis were employed to explore the function of SLC16A3 in pan-cancer. The resulting data demonstrated that SLC16A3 mRNA expression was overexpressed in most cancers and its protein expression was also high across diverse cancer types. Moreover, upregulated SLC16A3 expression was linked to poor OS and PFI of certain cancers. Cox regression analysis further indicated that SLC16A3 is a risk factor for patients with PAAD, CESC, LUSC, LUAD, CHOL, LGG, MESO, and OSCC. The ROC curve revealed that SLC16A3 exhibited a high accuracy (AUC > 0.9) in BRCA, CHOL, ESCA, GBM, and KIRC prediction. Moreover, the acquired data indicated that in pan-cancer, the SLC16A3 expression exhibited correlations with immune checkpoint genes and immune cells. These findings collectively suggest that SLC16A3 holds promise as a biomarker for diagnostic and prognostic purposes in pan-cancer.

Design and Synthesis of FR-β Targeting Chimeric Molecules for Reprogramming Tumor-Associated Macrophages Using 6-Substituted Pyrrolo[2,3-d]pyrimidines as Targeting Ligands

Tumor-associated macrophages (TAMs) are highly plastic tumor-infiltrating immune cells. Their reprogramming has emerged as a pivotal strategy in antitumor immunotherapy. The TLR7/8 agonist, IMDQ, has significant potential for reprogramming macrophages but lacks target specificity. To address this challenge, we developed novel folate receptor beta (FR-β) targeting chimeric molecules using 6-substituted pyrrolo[2,3-d]pyrimidines as high-affinity ligands, which demonstrate superior FR-β targeting capability compared with classical folic acid. These molecules integrate the FR-β targeting moiety with IMDQ, marking the first application of this immunomodulator in targeted chimeric constructs. In vitro and in vivo studies demonstrated that our chimeric molecules selectively reprogrammed TAMs toward an immunostimulatory phenotype, reshaped the tumor microenvironment, and inhibited tumor progression without systemic toxicity. Given that TAM accumulation is prevalent across all solid tumors, our strategy of precisely targeting and reprogramming of TAMs is universally applicable to treating various types of cancers, a potent and effective strategy for antitumor immunotherapy.

EGR2 promotes liver cancer metastasis by enhancing IL-8 expression through transcription regulation of PDK4 in M2 macrophages

Liver tumor is a common digestive system tumor, and its development is closely related to complex cytokines, tumor microenvironment and immunoregulatory mechanisms. Tumor-associated macrophages play a great role in a series of liver cancer development by secreting various cytokines and transmitting multiple signals, but how macrophages regulate the various biological behaviors of liver cancer cells at the microscopic level is a challenge we still need to overcome. In this research, we first identified the Early Growth Response 2 (EGR2) gene, which exhibited significant expression in M2 macrophages in comparison to M0 and M1 cell types, utilizing RNA sequencing. Subsequently, we validated this finding through a battery of methodologies, including WB, qRT-PCR, and immunofluorescence assays. We further employed a co-culture model involving MHCC97L and macrophages to investigate the impact of EGR2 downregulation within M2 cells on the in vivo and in vitro metastatic and invasive capabilities of MHCC97L cells. Subsequently, we directed our attention to investigating the impact of EGR2 on the levels of interleukin-8 (IL-8). Through comprehensive analyses including RNA sequencing, CUT-and-Tag, and ChIP techniques, we demonstrated that EGR2 can bind to the promoter region of the Pyruvate Dehydrogenase Kinase 4 (PDK4) gene. Finally, we introduced a virus overexpressing PDK4 and demonstrated that EGR2 could regulate the transcriptional level of PDK4 to affect the expression of IL-8, and ultimately alter the metastatic ability of hepatocellular carcinoma cells. Our study demonstrates that EGR2 may be a valuable target for future intervention in the disease process of hepatocellular carcinoma and refines the mechanism at the microscopic level of Tumor-associated macrophages.

Tumor organoid-immune co-culture models: exploring a new perspective of tumor immunity

Recent advancements in technology have significantly expanded the scope of tumor research, progressing from the study of individual cells to more intricate tissue and organ-level analyses. Tumor organoids have emerged as a highly realistic platform for investigating tumor growth, development, and their interactions with the surrounding microenvironment. However, a notable limitation of these organoids is their lack of the diverse cellular composition typically observed in actual tumors, which hinders their ability to fully replicate the complexity of the tumor microenvironment. Immune cells play a pivotal role, and tumor immunology has become a major research hotspot. Research in tumor immunology aims to elucidate how the immune system recognizes and attacks tumor cells, as well as how tumor cells evade immune surveillance. In recent years, there has been growing interest in co-culturing immune cells with tumor organoids, an approach that has yielded valuable insights into the intricate interactions between tumors and the immune system. The aim of this paper is to review and discuss the progress achieved in co-culturing tumor organoids with immune cells. By doing so, we hope to offer a new perspective and enhance our understanding of the complexity and diversity inherent in the tumor microenvironment.

Reprogramming and targeting of cholesterol metabolism in tumor-associated macrophages

Cholesterol, as a major component of cell membranes, is closely related to the metabolic regulation of cells and organisms; tumor-associated macrophages play an important push role in tumor progression. We know that tumor-associated macrophages are polarized from macrophages, and the abnormalities of cholesterol metabolism that may be induced during their polarization are worth discussing. This manuscript focuses on metabolic abnormalities in tumor-associated macrophages, and first provides a basic summary of the regulatory mechanisms of abnormal macrophage polarization. Subsequently, it comprehensively describes the features of abnormal glucose, lipid and cholesterol metabolism in TAMs as well as the different regulatory pathways. Then, the paper also discusses the link between abnormal cholesterol metabolism in TAMs and tumors, chronic diseases and aging. Finally, the paper summarizes cancer therapeutic strategies targeting cholesterol metabolism that are already in clinical trials, as well as nanomaterials capable of targeting cholesterol metabolism that are in the research stage, in the hope of providing value for the design of targeting materials. Overall, elucidating metabolic abnormalities in tumor-associated macrophages, particularly cholesterol metabolism, could provide assistance in tumor therapy and the design of targeted drugs.

6-Gingerol, an active compound of ginger, attenuates NASH-HCC progression by reprogramming tumor-associated macrophage via the NOX2/Src/MAPK signaling pathway

BACKGROUND

Non-alcoholic steatohepatitis-associated hepatocellular carcinoma (NASH-HCC) accounts for an increasing proportion of HCC cases. Currently, effective pharmacological options for treating both NASH and NASH-HCC remain limited, necessitating the identification of novel therapeutic agents. Our previous studies have demonstrated that ginger can ameliorate nonalcoholic fatty liver disease (NAFLD) and prevent the occurrence of NASH. The therapeutic effects and underlying mechanisms of NASH-HCC, however, remain poorly understood.

METHODS

Network pharmacology, bioinformatics, single-cell RNA sequencing analysis, and molecular docking were used to identify the main active compounds, targets, and possible mechanisms of ginger in treating NASH-HCC. The anti-tumor efficacy and underlying mechanisms of the selected compound in treating NASH-HCC were validated through in vitro experimentation.

RESULTS

Network pharmacology, bioinformatics, and molecular docking have revealed that 6-gingerol is the main active compound of ginger in treating NASH-HCC. SRC can be an essential target gene for ginger attenuating NASH-HCC progression, while the mitogen-activated protein kinase (MAPK) signaling pathway and reactive oxygen species (ROS) play equally important roles. Single-cell RNA sequencing of the HCC patients shows that the key targets of ginger in treating NASH-HCC are distributed in tumor-associated macrophage (TAMs). It has been reported that NOX2-derived ROS in macrophages can activate Src and then regulate downstream MAPK signaling cascades. 6-Gingerol can inhibit the proliferation, migration and reduce lipid deposition of liver cancer cells in vitro. More importantly, it induces polarization TAMs to M1 and enhances proinflammatory function, which may be achieved via the NOX2/Src/MAPK signaling pathway.

CONCLUSION

This study proves that 6-gingerol, the primary active compound in ginger, plays a role in attenuating the progression of NASH-HCC by inhibiting the proliferation and migration of tumor cells, or reprogramming TAMs to the M1 phenotype via the NOX2/Src/MAPK signaling pathway and activating the TAM-mediated immune responses.

Replication of patient specific circulating tumor cells on a microfibrous filter for drug screening

Personalized medicine in cancer treatment has the potential to enhance therapeutic efficacy while simultaneously reducing adverse effects. Molecular characterization of circulating tumor cells (CTCs) offers invaluable insight into metastatic tumor heterogeneity, making them a perfect candidate for metastatic cancer drug screening. However, they are extremely rare. This study presents the development of melt-electrowritten membrane filters designed for the capture, culture, and drug testing of CTCs. By varying the collector speeds, filters with optimized pore sizes and polymer densities were produced, enabling selective capture of CTCs while minimizing co-capture of white blood cells. Biocompatibility tests showed that the filter supported the proliferation of multiple cancer cell lines. The filter successfully captured and cultured colorectal cancer patient-derived CTC44 and CTC45 cells, which formed 3D clusters observable over several weeks. Drug testing with chemotherapeutic agents 5-fluorouracil/oxaliplatin (FOX) and 5-fluorouracil/irinotecan (FIRI) revealed that CTCs in 3D clusters on the filters exhibited significantly higher drug resistance compared to 2D monolayers. These findings demonstrate the potential of the filter as a versatile platform for studying CTC biology and for screening anticancer drugs, providing a more physiologically relevant environment than traditional 2D cultures.

Macrophage membrane entrapped rapamycin-loaded TPGS/F127 micelles through intratracheal instillation for enhanced drug delivery and therapy to lung cancer with pulmonary fibrosis

PURPOSE

Patients with pulmonary fibrosis are prone to developing lung cancer. Pulmonary fibrosis and lung cancer have many common pathogenic factors and similar pathological features. For patients with IPF combined with lung cancer, there is currently no better treatment method available now. The purpose of this study is to develop a rapamycin pulmonary administration preparation that can treat lung cancer with pulmonary fibrosis, thereby overcoming the limitations of rapamycin treatment.

METHODS

In this study, rapamycin-loaded mixed micelle nanoparticles (TPGS/F127@RAPA) were first prepared by the film dispersion method. Then biomimetic nanoparticles (MM@TPGS/F127@RAPA) were obtained by coating the surface of TPGS/F127@RAPA with macrophage membranes (MM) using a co-incubation method.

RESULTS

TPGS/F127@RAPA and MM@TPGS/F127@RAPA showed particle sizes of about 15 nm and 260 nm respectively. Transmission electron microscope results showed that TPGS/F127@RAPA and MM@TPGS/F127@RAPA had homogeneous spherical shape morphologies and that the TPGS/F127@RAPA core was successfully covered with the macrophage membrane. In vitro studies demonstrated that MM@TPGS/F127@RAPA could effectively inhibit the excessive proliferation and migration of A549 cells and activated-Mlg cells. Moreover, MM@TPGS/F127@RAPA could increase the uptake of rapamycin by cells. By inhibiting the TGF-β1/Smad3 and PI3K/AKT/mTOR signaling pathways, TPGS/F127@RAPA and MM@TPGS/F127@RAPA could further reduce collagen deposition, inhibit tumor cell proliferation and improve lung function. Mice suffering from lung cancer with pulmonary fibrosis were treated with MM@TPGS/F127@RAPA through intratracheal instillation. The results showed that compared with TPGS/F127@RAPA, MM@TPGS/F127@RAPA could better reduce the area of pulmonary fibrosis and collagen deposition, inhibit tumor cell proliferation and improve lung function, exhibit longer retention time in lung and better lung distribution and deposition.

CONCLUSION

Our results revealed that the biomimetic strategy of MM@TPGS/F127@RAPA may be a good choice for the treatment of lung cancer patients with pulmonary fibrosis.

Deciphering a crosstalk between biological cues and multifunctional nanocarriers in lung cancer therapy

In recent years, the utilization of nanocarriers has significantly broadened across a diverse spectrum of biomedical applications. However, the clinical translation of these tiny carriers is limited and encounters hurdles, particularly in the intricate landscape of the tumor microenvironment. Lung cancer poses unique hurdles for nanocarrier design. Multiple physiological barriers hinder the efficient drug delivery to the lungs, such as the complex anatomy of the lung, the presence of mucus, immune responses, and rapid clearance mechanisms. Overcoming these obstacles necessitates a targeted approach that minimizes off-target effects while effectively penetrating nanoparticles/cargo into specific lung tissues or cells. Furthermore, understanding the cellular uptake mechanisms of these nano carriers is also essential. This knowledge aids in developing nanocarriers that efficiently enter cells and transfer their payload for the most effective therapeutic outcome. Hence, a thorough understanding of biological cues becomes crucial in designing multifunctional nanocarriers tailored for treating lung cancer. This review explores the essential biological cues critical for developing a flexible nanocarrier specifically intended to treat lung cancer. Additionally, it discusses advancements in nanotheranostics in lung cancer.

Matrix Metalloproteinases in Glioma: Drivers of Invasion and Therapeutic Targets

Matrix metalloproteinases (MMPs) are a family of zinc-dependent proteolytic enzymes that are crucial for the remodeling of the extracellular matrix, a process that is often co-opted by cancers, including brain tumors, to facilitate growth, invasion, and metastasis. In gliomas, MMPs contribute to a complex interplay involving tumor proliferation, angiogenesis, and immune modulation, thereby influencing tumor progression and patient prognosis. This review provides a comprehensive analysis of the roles of various MMPs in different types of gliomas, from highly malignant gliomas to metastatic lesions. Emphasis is placed on how the dysregulation of MMPs impacts tumor behavior, the association between specific MMPs and the tumor grade, and their potential as biomarkers for diagnosis and prognosis. Additionally, the current therapeutic approaches targeting MMP activity are discussed, exploring both their challenges and future potential. By synthesizing recent findings, this paper aims to clarify the broad significance of MMPs in gliomas and propose avenues for translational research that could enhance treatment strategies and clinical outcomes.

Amyloid precursor-like protein 2 expression in macrophages: differentiation and M1/M2 macrophage dynamics

Amyloid precursor-like protein 2 (APLP2) has been previously associated with pro-tumor phenotypes in cancer cells, and in this current study we investigated the expression and functions of this protein in macrophages. Our findings showed that APLP2 expression was increased in monocyte-like U937 cells after cytokine-induced differentiation to macrophage-like cells. Evaluation of human mRNA data revealed that APLP2 is more highly expressed in human M2/anti-inflammatory (pro-tumor) macrophages than in M1 macrophages (which have a pro-inflammatory, anti-tumor phenotype). Consistent with the mRNA data, by immunoblotting we identified increased APLP2 protein expression in mouse M2/anti-inflammatory macrophages. Intratumoral infiltration of M2/anti-inflammatory macrophages has been reported in several cancers, including neuroblastoma (NB). We observed that treatment of macrophages with NB-conditioned media induced M2/anti-inflammatory and mixed phenotypes. Through comparison of macrophages from wild-type and APLP2-knockout mice, we correlated alterations in inflammation-associated markers with the presence of APLP2. This suggests that APLP2 influences macrophage polarization dynamics between M0/unpolarized and pro- and anti-inflammatory states, and populations altered by APLP2 KO resemble the macrophage profiles altered with NB-conditioned media treatment. In total, our work implicates APLP2 as a mediator of macrophage status, namely in the M0/unpolarized macrophage and the M1/pro-inflammatory and M2/anti-inflammatory axis.

Acinar cells modulate the tumor microenvironment through the promotion of M1 macrophage polarization via macrophage endocytosis in pancreatic cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDA) is a highly aggressive and fatal cancer. M1 macrophages are generally considered to have anti-tumor properties, capable of suppressing tumor growth and metastasis by secreting pro-inflammatory cytokines and enhancing the immune response.

AIMS

The objective of this research was to pinpoint crucial genes associated with M1 macrophages and search for a new way to activate the M1 phenotype of macrophages in PDA.

METHODS

The level of immune cell infiltration was assessed using CIBERSORT in TCGA-PAAD cohort and ICGC-PACA cohort. We performed weighted gene co-expression network analysis (WGCNA) to identify the module most correlated with M1 macrophages and we identified hub genes through protein-protein interaction (PPI) analyse. Through survival analysis, correlation analysis and single cell analysis, we obtained the relationship between hub genes and prognosis, and the relationship between key genes and immune cells, as well as its expression in various cells.

RESULTS

PRSS1 (Cationic trypsinogen) and CTRB1 (Chymosinogen B) were hub genes of the M1 macrophage-associated WGCNA module (211genes) and are closely related to the extension of survival time, which are also verified as cell growth-related genes by DepMap database. Through single-cell sequencing analysis, we determined that the expression levels of PRSS1 and CTRB1 in the acinar cells of tumor tissues were diminished. PRSS1 and CTRB1 are considered to be the signature genes of acinar cells. The proportion of acinar cells was also correlated with the infiltration of CD8T cells and M1 cells. Immunostaining revealed elevated expression levels of PRSS1 and CTRB1 in adjacent normal tissues. Cell line experiments confirmed that macrophages polarize towards M1 by engulfing pancreatic enzyme granules, thereby inhibiting the malignant phenotype of tumor cells.

CONCLUSION

Our findings highlight the critical role of acinar cells in modulating the immune microenvironment of pancreatic tumors by influencing macrophage polarization. This insight may provide novel opportunities for therapeutic interventions in cancer treatment.

The role of immunotherapy in targeting tumor microenvironment in genitourinary cancers

Genitourinary (GU) cancers, including renal cell carcinoma, prostate cancer, bladder cancer, and testicular cancer, represent a significant health burden and are among the leading causes of cancer-related mortality worldwide. Despite advancements in traditional treatment modalities such as chemotherapy, radiotherapy, and surgery, the complex interplay within the tumor microenvironment (TME) poses substantial hurdles to achieving durable remission and cure. The TME, characterized by its dynamic and multifaceted nature, comprises various cell types, signaling molecules, and the extracellular matrix, all of which are instrumental in cancer progression, metastasis, and therapy resistance. Recent breakthroughs in immunotherapy (IO) have opened a new era in the management of GU cancers, offering renewed hope by leveraging the body's immune system to combat cancer more selectively and effectively. This approach, distinct from conventional therapies, aims to disrupt cancer's ability to evade immune detection through mechanisms such as checkpoint inhibition, therapeutic vaccines, and adoptive cell transfer therapies. These strategies highlight the shift towards personalized medicine, emphasizing the importance of understanding the intricate dynamics within the TME for the development of targeted treatments. This article provides an in-depth overview of the current landscape of treatment strategies for GU cancers, with a focus on IO targeting the specific cell types of TME. By exploring the roles of various cell types within the TME and their impact on cancer progression, this review aims to underscore the transformative potential of IO strategies in TME targeting, offering more effective and personalized treatment options for patients with GU cancers, thereby improving outcomes and quality of life.

Bufalin inhibits immune escape in metastatic colorectal cancer by regulating M2 macrophage polarization

The prognosis for patients with metastatic colorectal cancer (mCRC) remains poor primarily owing to immune escape caused by immunosuppressive tumor microenvironment (TME). M2 tumor-associated macrophages (TAMs) have been considered as a pivotal role in sustaining the immunosuppressive character in TME. Our previous studies have found that highly mCRC cells could promote M2 TAMs polarization, leading to the exhaustion of T cell antitumor immunity. Studies have reported that Bufalin (BU) could reverse the immunosuppressive TME via regulating TAMs polarization, but the mechanisms underlying remain elusive. In this study, we demonstrated that KLF4 secreted by highly mCRC cells not only promoted the polarization to M2 TAMs but also up-regulated the PD-L1 expression in TAMs, leading to suppressing cytotoxic T lymphocyte (CTL) function to facilitate tumor immune escape. Mechanistically, BU targeted the SRC-3 protein to reduce KLF4 release in highly mCRC cells to regulate the polarization of M2 TAMs and down-regulate PD-L1 expression in TAMs, resulting in reprogramming of the TME and enhancing the anti-tumor immunity. These results have also been validated in both subcutaneous tumor models and orthotopic tumor models. Overall, this research further elucidates the anti-tumor mechanism of BU for inhibiting immune escape in mCRC and facilitate exploitation of a new potential macrophage-based mCRC immunotherapeutic modality.

Modulation of M1 and M2 macrophage polarization by metformin: Implications for inflammatory diseases and malignant tumors

Macrophages perform an essential role in the body's defense mechanisms and tissue homeostasis. These cells exhibit plasticity and are categorized into two phenotypes, including classically activated/M1 pro-inflammatory and alternatively activated/M2 anti-inflammatory phenotypes. Functional deviation in macrophage polarization occurs in different pathological conditions that need correction. In addition to antidiabetic impacts, metformin also possesses multiple biological activities, including immunomodulatory, anti-inflammatory, anti-tumorigenic, anti-aging, cardioprotective, hepatoprotective, and tissue-regenerative properties. Metformin can influence the polarization of macrophages toward M1 and M2 phenotypes. The ability of metformin to support M2 polarization and suppress M1 polarization could enhance its anti-inflammatory properties and potentiate its protective effects in conditions such as chronic inflammatory diseases, atherosclerosis, and obesity. However, in metformin-treated tumors, the proportion of M2 macrophages is decreased, while the frequency ratio of M1 macrophages is increased, indicating that metformin can modulate macrophage polarization from a pro-tumoral M2 state to an anti-tumoral M1 phenotype in malignancies. Metformin affects macrophage polarization through AMPK-dependent and independent pathways involving factors, such as NF-κB, mTOR, ATF, AKT/AS160, SIRT1, STAT3, HO-1, PGC-1α/PPAR-γ, and NLRP3 inflammasome. By modulating cellular metabolism and apoptosis, metformin can also influence macrophage polarization. This review provides comprehensive evidence regarding metformin's effects on macrophage polarization and the underlying mechanisms. The polarization-inducing capabilities of metformin may provide significant therapeutic applications in various inflammatory diseases and malignant tumors.

Phosphoinositide kinases in cancer: from molecular mechanisms to therapeutic opportunities

Phosphoinositide kinases, extending beyond the well-known phosphoinositide 3-kinase (PI3K), are key players in the dynamic and site-specific phosphorylation of lipid phosphoinositides. Unlike PI3Ks, phosphatidylinositol 4-kinases (PI4Ks) and phosphatidylinositol phosphate kinases (PIPKs) do not usually exhibit mutational alterations, but mostly show altered expression in tumours, orchestrating a broad spectrum of signalling, metabolic and immune processes, all of which are crucial in the pathogenesis of cancer. Dysregulation of PI4Ks and PIPKs has been associated with various malignancies, which has sparked considerable interest towards their therapeutic targeting. In this Review we summarize the current understanding of the lesser-studied phosphoinositide kinase families, PI4K and PIPK, focusing on their functions and relevance in cancer. In addition, we provide an overview of ongoing efforts driving the preclinical and clinical development of phosphoinositide kinase-targeting molecules.

APOC1 knockdown induces apoptosis and decreases angiogenesis in diffuse large B-cell lymphoma cells through blocking the PI3K/AKT/mTOR pathway

Diffuse large B-cell lymphoma (DLBCL) is a highly heterogeneous metastatic lymphoma that can be treated by targeting angiogenesis. Apolipoprotein C1 (APOC1) plays a significant role in the proliferation and metastasis of various malignant tumors; however, its role in DLBCL-particularly its effects on angiogenesis-remains largely unexplored. This study investigates the correlation between APOC1 expression and patient prognosis in DLBCL. Using APOC1 gene knockdown, apoptosis, migration, and invasion were assessed through flow cytometry, the EDU assay, wound healing, and Transwell assays. Additionally, human umbilical vein endothelial cells (HUVEC) angiogenesis was evaluated. Advanced techniques, such as immunofluorescence, TUNEL assay, and immunohistochemical labeling were employed to analyze the effects of APOC1 knockdown on the PI3K/AKT/mTOR signaling pathway and tumor formation in nude mice. Results showed that APOC1 is overexpressed in DLBCL tissues and cells, with high APOC1 levels associated with poor patient prognosis. In vitro experiments revealed that APOC1 knockdown increased apoptosis and inhibited cell proliferation, migration, invasion, HUVEC angiogenesis, and PI3K/AKT/mTOR signaling pathway protein expression in DLBCL cells. Similarly, in vivo studies demonstrated that APOC1 knockdown significantly reduced tumor growth, angiogenesis-related proteins, and phosphorylated PI3K/AKT/mTOR pathway proteins in nude mice. APOC1 knockdown promotes apoptosis and suppresses angiogenesis in DLBCL cells by inhibiting the PI3K/AKT/mTOR pathway.

Construction and significance of a breast cancer prognostic model based on cuproptosis-related genotyping and lncRNAs

BACKGROUND/PURPOSE

Cuproptosis may play a significant role in breast cancer (BC). We aimed to investigate the prognostic impact of cuproptosis-related lncRNAs in BC.

METHODS

Consensus clustering analysis categorized TCGA-BRCA samples into 3 clusters, followed by survival and immune analyses of the 3 clusters. LASSO-COX analysis was performed on cuproptosis-related lncRNAs differentially expressed in BC to construct a BC prognostic model. Gene Ontology/Kyoto Encyclopedia of Genes and Genomes (GO/KEGG) enrichment, immune, and drug prediction analyses were performed on the high-risk and low-risk groups. Cell experiments were conducted to analyze the results of drug prediction and two cuproptosis-related lncRNAs (AC104211.1 and LINC01863).

RESULTS

Significant differences were observed in survival outcomes and immune infiltration levels among the three clusters (p < 0.05). The validation of the model showed significant differences in survival outcomes between the high-risk and low-risk groups in both the training and validation sets (p < 0.05). Differential mRNAs between the two groups were significantly enriched in the Neuroactive ligand-receptor interaction and cAMP signaling pathway. Additionally, significant differences were found in immune infiltration levels, human leukocyte antigen (HLA) expression, Immunophenoscore (IPS) scores, and Tumor Immune Dysfunction and Exclusion (TIDE) scores between the two groups (p < 0.05). Drug prediction and corresponding cell experimental results showed that Trametinib, 5-fluorouracil, and AICAR significantly inhibited the viability of MCF-7 cells (p < 0.05). AC104211.1 and LINC01863 were found to impact the proliferation of BC cells.

CONCLUSION

The risk-scoring model obtained in this study may serve as a robust prognostic biomarker, potentially aiding in clinical decision-making for BC patients.

Microglial Depletion, a New Tool in Neuroinflammatory Disorders: Comparison of Pharmacological Inhibitors of the CSF-1R

A growing body of evidence highlights the importance of microglia, the resident immune cells of the CNS, and their pro-inflammatory activation in the onset of many neurological diseases. Microglial proliferation, differentiation, and survival are highly dependent on the CSF-1 signaling pathway, which can be pharmacologically modulated by inhibiting its receptor, CSF-1R. Pharmacological inhibition of CSF-1R leads to an almost complete microglial depletion whereas treatment arrest allows for subsequent repopulation. Microglial depletion has shown promising results in many animal models of neurodegenerative diseases (Alzheimer's disease (AD), Parkinson's disease, or multiple sclerosis) where transitory microglial depletion reduced neuroinflammation and improved behavioral test results. In this review, we will focus on the comparison of three different pharmacological CSF-1R inhibitors (PLX3397, PLX5622, and GW2580) regarding microglial depletion. We will also highlight the promising results obtained by microglial depletion strategies in adult models of neurological disorders and argue they could also prove promising in neurodevelopmental diseases associated with microglial activation and neuroinflammation. Finally, we will discuss the lack of knowledge about the effects of these strategies on neurons, astrocytes, and oligodendrocytes in adults and during neurodevelopment.

Synchronously Delivering Melittin and Evoking Ferroptosis via Tumor Microenvironment-Triggered Self-Destructive Metal-Organic Frameworks to Boost Cancer Immunotherapy

The primary goal of treating malignant tumors is to efficiently eliminate the primary tumor and prevent metastasis and recurrence. Unfortunately, the immunosuppressive tumor microenvironment (TME) is a significant obstacle to effective oncotherapy. Herein, a therapeutic strategy based on melittin (MLT) encapsulated in hyaluronic acid-modified metal-organic frameworks (MOFs) is pioneered, focusing on the safe delivery and TME-responsive release of MLT to reshaping the immunosuppressive TME and simultaneously activating the immune system to eradicate cancerous cells. Iron-based MOFs respond to glutathione and pH, degrade within a moderately acidic TME, and achieve tumor-specific release of MLT. Additionally, the iron-mediated Fenton reaction produces reactive oxygen species that augment oxidative stress, ultimately leading to tumor-specific ferroptosis, whereas MLT-induced membrane disruption promotes immunogenic cell death to activate the immune system. In combination with the immune checkpoint inhibitor anti-PD-L1, this nanodrug elicits potent antitumor immune responses, facilitating the infiltration of effector T cells and enhancing systemic antitumor T cell immunity to suppress both primary and distant tumors. This study demonstrates the tremendous potential of nanoscale self-destructive MOFs for the targeted transport and controlled release of MLT and reveals the promoting effect of combined MLT and ferroptosis delivery on cancer immunotherapy.

Quantitative characterization of tissue states using multiomics and ecological spatial analysis

The spatial organization of cells in tissues underlies biological function, and recent advances in spatial profiling technologies have enhanced our ability to analyze such arrangements to study biological processes and disease progression. We propose MESA (multiomics and ecological spatial analysis), a framework drawing inspiration from ecological concepts to delineate functional and spatial shifts across tissue states. MESA introduces metrics to systematically quantify spatial diversity and identify hot spots, linking spatial patterns to phenotypic outcomes, including disease progression. Furthermore, MESA integrates spatial and single-cell multiomics data to facilitate an in-depth, molecular understanding of cellular neighborhoods and their spatial interactions within tissue microenvironments. Applying MESA to diverse datasets demonstrates additional insights it brings over prior methods, including newly identified spatial structures and key cell populations linked to disease states. Available as a Python package, MESA offers a versatile framework for quantitative decoding of tissue architectures in spatial omics across health and disease.

Tumor-Derived Exosomal circ_0020095 Promotes Colon Cancer Cell Proliferation and Metastasis by Inhibiting M1 Macrophage Polarization

Tumor-associated macrophages (TAM) have been shown to regulate colon cancer (CC) progression. However, it is not clear whether tumor-derived exosomal circular RNA (circRNA) regulates TAM to influence CC progression. The expression levels of circ_0020095, M1 macrophage markers, M2 macrophage markers, and interleukin-1 receptor-associated kinase 1 (IRAK1) were determined by qRT-PCR. Cell proliferation, migration and invasion were examined by EdU assay, wound healing assay and transwell assay. Exosomes derived from CC cells were used to treat M0 macrophages. M1 macrophage surface marker CD86 was detected by flow cytometry, and protein expression was examined by western blot. Then, the medium of exosome-treated M0 macrophages was used to culture CC cells to determine CC cell functions. RNA pull-down assay, RIP assay and dual-luciferase reporter assay were performed to validate interaction. Circ_0020095 had elevated expression in CC tissues and cells, and its knockdown repressed CC cell proliferation and metastasis. M0 macrophages could take by CC cell-derived exosomes to regulate circ_0020095 expression. Exosomal circ_0020095 restrained M1 macrophage polarization and increased M2 macrophage polarization to enhance CC cell progression. Besides, IRAK1 silencing could promote CC cell proliferation and metastasis by inhibiting M1 macrophage polarization, and its overexpression also abolished the effect of exosomal circ_0020095. Mechanistically, circ_0020095 could competitively bind to IGF2BP1 and then reduced the binding ability of IGF2BP1 and IRAK1 3'UTR. Tumor-derived exosomal circ_0020095 promoted CC cell progression via inhibiting M1 macrophage polarization through IGF2BP1/IRAK1 axis.

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.

Thiostrepton suppresses intrahepatic cholangiocarcinoma progression via FOXM1-mediated tumor-associated macrophages reprogramming

Intrahepatic cholangiocarcinoma (ICC) is an aggressive cancer with an extremely poor prognosis, highlighting the urgent need for new treatment options. Recent studies increasingly suggest that the Forkhead box M1 (FOXM1) transcription factor may serve as a candidate target for cancer immunotherapy. However, its role and the underlying molecular mechanisms in ICC remain not fully understood. Here, we identify thiostrepton (TST) as a potent FOXM1 inhibitor, capable of exerting "dual anti-tumor" effects in ICC. On one hand, TST effectively suppresses tumor cell proliferation and metastasis. On the other hand, TST treatment improves the tumor immune microenvironment by reprogramming tumor-associated macrophages (TAMs), thereby enhancing anti-tumor immune responses. Mechanistically, TST directly alleviates ICC progression by arresting the cell cycle, promoting apoptosis, and inhibiting the epithelial-mesenchymal transition (EMT) process. Furthermore, TST-treated tumor cells secrete cytokines that drive TAMs repolarization toward the tumor-suppressive M1 phenotype. Overall, our results indicate that FOXM1 can serve as a novel target for ICC immunotherapy. By targeting FOXM1, TST exerts "dual anti-tumor" effects and has the potential to become a promising immunotherapy agent for ICC patients.

A novel PET tracer for noninvasive imaging the checkpoints expression of innate and adaptive immunity in tumors by simultaneously targeting CD24 and PD-L1

The success of tumor immunotherapy depends on the innate and adaptive immune responses, with CD24 and PD-L1 being key targets. DBP1 peptide is a novel bispecific D-peptide, targeting both CD24 and PD-L1 simultaneously. In this study, by radiolabeling DBP1 peptide, we developed a novel PET modality to noninvasively evaluate CD24 and PD-L1 expressions in tumors. To enhance the solubility of DBP1, a hydrophilic lysine was added into C-terminal residue of the peptide, which was then modified with a chelator NOTA to produce the radiotracer precursor NOTA-DBP1k. NOTA-DBP1k showed high affinity for CD24 (KD = 10.70 ± 0.70 nM) and PD-L1 (KD = 5.40 ± 0.61 nM). [68Ga]Ga-NOTA-DBP1k was synthesized with a high radiochemical yield (71 ± 3.0 %) and exhibited high hydrophilicity and stability. [68Ga]Ga-NOTA-DBP1k showed higher uptake in high CD24/PD-L1 expressed MCF-7 cells than that in low CD24/PD-L1 expressed U-87MG cells in vitro. In vivo, [68Ga]Ga-NOTA-DBP1k showed high uptake in MCF-7 tumors and had favorable tumor-to-background ratios by microPET imaging. On the contrary, low uptake was found in U-87MG tumors, which was significantly lower than that in MCF-7 tumors (0.42 ± 0.02 %ID/g vs. 1.01 ± 0.06 %ID/g, p < 0.05). The biodistribution study was consistent with the findings of microPET imaging results. These results demonstrated that [68Ga]Ga-NOTA-DBP1k can noninvasively image the CD24 and PD-L1 checkpoint expression of innate and adaptive immunity in tumors and may be helpful for guiding the CD24/PD-L1 dual-checkpoints blockage immunotherapy.

Key immune cells and their crosstalk in the tumor microenvironment of bladder cancer: insights for innovative therapies

Bladder cancer (BC) is a heterogeneous disease associated with high mortality if not diagnosed early. BC is classified into non-muscle-invasive BC (NMIBC) and muscle-invasive BC (MIBC), with MIBC linked to poor systemic therapy response and high recurrence rates. Current treatments include transurethral resection with Bacillus Calmette-Guérin (BCG) therapy for NMIBC and radical cystectomy with chemotherapy and/or immunotherapy for MIBC. The tumor microenvironment (TME) plays a critical role in cancer progression, metastasis, and therapeutic efficacy. A comprehensive understanding of the TME's complex interactions holds substantial translational significance for developing innovative treatments. The TME can contribute to therapeutic resistance, particularly in immune checkpoint inhibitor (ICI) therapies, where resistance arises from tumor-intrinsic changes or extrinsic TME factors. Recent advancements in immunotherapy highlight the importance of translational research to address these challenges. Strategies to overcome resistance focus on remodeling the TME to transform immunologically "cold" tumors, which lack immune cell infiltration, into "hot" tumors that respond better to immunotherapy. These strategies involve disrupting cancer-microenvironment interactions, inhibiting angiogenesis, and modulating immune components to enhance anti-tumor responses. Key mechanisms include cytokine involvement [e.g., interleukin-6 (IL-6)], phenotypic alterations in macrophages and natural killer (NK) cells, and the plasticity of cancer-associated fibroblasts (CAFs). Identifying potential therapeutic targets within the TME can improve outcomes for MIBC patients. This review emphasizes the TME's complexity and its impact on guiding novel therapeutic approaches, offering hope for better survival in MIBC.

Nano-strategies for Targeting Tumor-Associated Macrophages in Cancer immunotherapy

Tumor-associated macrophages (TAMs) are one type of the most abundant immune cells within tumor, resulting in immunosuppresive tumor microenvironment and tumor resistance to immunotherapy. Thus, targeting TAMs is a promising therapeutic strategy for boosting cancer immunotherapy. This study provides an overview of current therapeutic strategies targeting TAMs, which focus on blocking the recruitment of TAMs by tumors, regulating the polarization of TAMs, and directly eliminating TAMs using various nanodrugs, especially with a new categorization based on the specific signaling pathways, such as NF-κB, HIF-1α, ROS, STAT, JNK, PI3K, and Notch involved in their regulatory mechanism. The latest developments of nanodrugs modulating these pathways are discussed in determining the polarization of TAMs and their role in the tumor microenvironment. Despite the challenges in clinical translation and the complexity of nanodrug synthesis, the potential of nanodrugs in enhancing the effectiveness of cancer immunotherapy is worthy of expecting.

Lidocaine Modulates Cytokine Production and Reprograms the Tumor Immune Microenvironment to Enhance Anti-Tumor Immune Responses in Gastric Cancer

Lidocaine, a local anesthetic, has been shown to modulate immune responses. This study examines its effects on cytokine production in peripheral blood mononuclear cells (PBMCs) from healthy donors and tumor-infiltrating immune cells (TIICs) from gastric cancer patients. PBMCs from healthy donors and TIICs from gastric cancer patients were treated with lidocaine. Cytokine production was assessed using flow cytometry and cytokine assays, with a focus on IFN-γ, IL-12, IL-10, TGF-β, and IL-35 levels. Cytotoxicity against primary gastric cancer cells (PGCCs) was also evaluated. Lidocaine inhibited IFN-γ production in CD8+ PBMCs and IL-12 in CD14+ PBMCs while increasing anti-inflammatory cytokines (IL-10, TGF-β, IL-35) in CD4+CD25+ and CD14+ cells. In TIICs, lidocaine enhanced IFN-γ and IL-12 production in CD8+ and CD14+ cells while reducing IL-10, TGF-β, and IL-35 levels, promoting an M1-like phenotype in macrophages. Mechanistically, lidocaine enhanced IFN-γ production in sorted CD8+ TIICs through G-protein-coupled receptor (GPCR) signaling and increased IL-12 production in sorted CD14+ TIICs via the toll-like receptor 4 (TLR4) signaling pathway. Lidocaine also increased IFN-γ production and cytotoxicity in CD8+ TIICs via NF-κB activation. Importantly, lidocaine did not affect the viability of PBMCs, TIICs, or PGCCs at concentrations up to 1.5 mM. Lidocaine reprogrammed the tumor immune microenvironment, enhancing anti-tumor immune responses, suggesting its potential to modulate immune functions in gastric cancer.

Histone acetylation modulators in breast cancer

Breast cancer is the most prevalent cancer in women worldwide. Aberrant epigenetic reprogramming such as dysregulation of histone acetylation has been associated with the development of breast cancer. Histone acetylation modulators have been targeted as potential treatments for breast cancer. This review comprehensively discusses the roles of these modulators and the effects of their inhibitors on breast cancer. In addition, epigenetic reprogramming not only affects breast cancer cells but also the immunosuppressive myeloid cells, which can facilitate breast cancer progression. Therefore, the review also highlights the roles of these immunosuppressive myeloid cells and summarizes how histone acetylation modulators affect their functions and phenotypes. This review provides insights into histone acetylation modulators as potential therapeutic targets for breast cancer.