In prior research, both miRNA-125b and BLZ945 have shown potential in effectively inhibiting M2 macrophage polarization and producing antitumor effects. Nevertheless, their physicochemical characteristics present significant challenges for efficient in vivo delivery. Ionizable cationic lipid nanoparticles (LNPs), recognized for their superior biocompatibility and drug-loading capacity, serve as a novel carrier for nucleic acid-based therapeutics. In our study, we successfully encapsulated both agents within LNPs and conducted a thorough characterization. Subsequently, we investigated their potential to repolarize M2 macrophages in vitro and evaluated their in vivo distribution, biosafety, and antitumor efficacy. The findings revealed that the LNPs maintained excellent drug-loading efficiency, consistent particle size, and stable zeta potential. All formulations effectively inhibited M2 macrophage polarization in vitro. Upon administration in vivo, the LNPs not only demonstrated favorable biosafety profiles but also accumulated efficiently in tumor tissues, substantially reducing tumor burden, particularly notable in co-loaded LNPs. Our results affirm that LNPs are an effective carrier for miRNA-125b and BLZ945, highlighting this encapsulation approach as promising for the treatment of solid tumors and meriting further investigation. Practitioner points: (i) Ionizable cationic nanoparticles provide high and stable encapsulation rates to efficiently load nucleic acid polymers into the LNP, avoiding the rapid accumulation of circulating macrophages, which can lead to reduced penetration of the LNP into target tissues. Therefore, it can be used as a novel drug delivery method to benefit clinical patients. (ii) miRNA-125b LNP/BLZ945 LNP attenuated the depleting effect of BLZ945 on macrophages and significantly inhibited macrophage M2 polarization. It could be effectively distributed in tumors and showed good biosafety while exerting antitumor effects, bringing hope to clinical pancreatic tumor patients.

Immune checkpoint inhibitors (ICIs) have shifted the treatment paradigm of non-small cell lung cancer (NSCLC) over the last decade. Despite notable therapeutic advancements in responders, the response rate remains limited owing to the immunosuppressive tumor microenvironment (TME). Therefore, to improve the efficacy of ICIs, it is essential to explore alternative targets or signals that mediate immunosuppression. Immunoglobulin-like transcript (ILT) 5 is a negative regulator of immune activation in myeloid cells. However, the expression and function of ILT5 in NSCLC remain unknown. Here, we found that ILT5 was highly expressed in tumor-associated macrophages (TAMs) of NSCLC tissues and predicted poor patient survival. Functionally, ILT5 induces the M2-like polarization of TAMs, which subsequently decreases the density of T cells, and increases FOXP3+T cell accumulation, leading to an immunosuppressive TME. The combination of ILT5 expression with M2-like TAM density is a more reliable biomarker of patient survival than ILT5 expression alone. ILT5 knockout mitigates the reprogramming of TAM and T cell subsets toward immunosuppressive phenotypes and inhibits tumor growth in vivo. These findings highlight that ILT5 is a potential immunotherapeutic target and a promising prognostic biomarker for NSCLC.

Liver cancer prognosis is associated with M0 macrophages and lipid metabolism reprogramming; however, the prognostic role of M0 macrophage-related lipid metabolism genes in hepatocellular carcinoma (HCC) remains unclear.

We identified 153 lipid metabolism genes associated with M0 macrophage infiltration in HCC from The Cancer Genome Atlas (TCGA) and the Molecular Signatures Database (MSigDB). Prognostic genes were selected, and a model was constructed using least absolute shrinkage and selection operator (LASSO) and Cox regression analyses. The model was validated using the International Cancer Genome Consortium (ICGC) database. We assessed the expression levels of prognostic genes by quantitative real-time polymerase chain reaction (qRT‒PCR).

A prognostic model was developed based on five characteristic genes. Receiver operating characteristic curve analysis demonstrated that the model had good accuracy, with area under the curve values of 0.796, 0.732, and 0.728 for predicting survival at 1, 3, and 5 years, respectively. The high-risk group exhibited increased sensitivity to common chemotherapy drugs, including sorafenib, dasatinib, and 5-fluorouracil, compared with the low-risk group (P < 0.05). Additionally, the high-risk group had significantly more infiltrating M0 macrophages, resting dendritic cells, follicular helper T cells, and regulatory T cells than did the low-risk group (P < 0.05). The qRT‒PCR results confirmed the upregulation of these five characteristic genes in HCC tissues.

M0 macrophage-associated lipid metabolism genes may serve as biomarkers for the prognosis of patients with HCC and as targets for immunotherapy.

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.

Virtual staining is an artificial intelligence-based approach that transforms pathology images between stain types, such as hematoxylin and eosin (H&E) to immunohistochemistry (IHC), providing a tissue-preserving and efficient alternative to traditional IHC staining. However, existing methods for translating H&E to virtual IHC often fail to generate images of sufficient quality for accurately delineating cell nuclei and IHC+ regions. To address these limitations, we introduce VISTA, an artificial intelligence-based virtual staining platform designed to translate H&E into virtual IHC.

We applied VISTA to identify M2-subtype tumor-associated macrophages (M2-TAMs) in H&E images from 968 patients with HPV+ oropharyngeal squamous cell carcinoma across six institutional cohorts. M2-TAMs are a critical component of the tumor microenvironment, and their increased presence has been linked to poor survival. Co-registered H&E and CD163 + IHC tissue microarrays were used to train (D1, N = 102) and test (D2, N = 50) the VISTA platform. M2-TAM density, defined as the ratio of M2-TAMs to total nuclei, was derived from VISTA-generated CD163 + IHC images and evaluated for prognostic significance in additional training (D3, N = 360) and testing (D4, N = 456) cohorts using biopsy or resection H&E whole slide images.

High M2-TAM density was associated with worse overall survival in D4 (p = 0.0152, Hazard Ratio=1.63 [1.1-2.42]). VISTA outperformed existing methods, generating higher-quality virtual CD163 + IHC images in D2, with a Structural Similarity Index of 0.72, a Peak Signal-to-Noise Ratio of 21.5, and a Fréchet Inception Distance of 41.4. Additionally, VISTA demonstrated superior performance in segmenting M2-TAMs in D2 (Dice=0.74).

These findings establish VISTA as a computational platform for generating virtual IHC and facilitating the discovery of novel biomarkers from H&E images.

Acral lentiginous melanoma (ALM) is a rare melanoma subtype primarily located in acral regions. However, ALMs exhibit a distinctive genetic profile characterized by a high number of copy number variations (CNVs) and limited point mutations. Late diagnosis and restricted therapeutic efficacy contribute to its poor prognosis. The secretome within the tumor microenvironment (TME) influences immune modulation and plays a vital role in melanoma progression. We aim to analyze the role of ALM secretome and CNVs profile with prognosis in primary ALM patients. Here, we demonstrated that high CNV burden (CNVsHigh) was associated with worse clinicopathological characteristics and poor prognosis. Furthermore, our study also revealed that conditioned media (CM) of CNVsHigh genetic profile ALM cell line was associated with pro-tumoral, pro-angiogenic, and immunosuppressive secretome profiles. In addition, CM of CNVsHigh cell lines in vitro promotes macrophage polarization to immunosuppressive phenotype. Moreover, we observed an increased presence of immunosuppressive tumor-associated macrophages (TAMs) at the invasive front (IF) of CNVsHigh ALM biopsies. This research reveals the adverse prognostic impact of CNVsHigh in ALM patients, establishing a novel link with a pro-tumor secretome, offering potential biomarkers for prognosis and personalized treatment to enhanced disease monitoring in ALM patients.

Sarcomas are a heterogeneous group of malignancies with limited therapeutic options, particularly in the metastatic setting. Adoptive cellular therapies (ACTs), including tumor-infiltrating lymphocyte (TIL) therapy, chimeric antigen receptor (CAR) T-cell therapy, and T-cell receptor (TCR) gene-modified T-cell therapy, offer promising novel approaches for these refractory tumors. TIL-based therapy has demonstrated early efficacy in melanoma and myeloma, with ongoing trials exploring its role in sarcoma. CAR T-cell strategies targeting HER2, GD2, and B7-H3 antigens are in development, though challenges such as tumor microenvironment-mediated resistance and antigen escape remain significant. Engineered TCRs, particularly those targeting MAGE-A4 and NY-ESO-1, have shown promising clinical results in synovial sarcoma (SS) and myxoid/round cell liposarcoma (MRCLS), leading to the recent FDA approval of afamitresgene autoleucel (afami-cel) and letetresgene autoleucel (lete-cel). Despite encouraging preliminary data, ACT implementation faces barriers including limited antigen specificity, off-tumor toxicity, immune evasion, and manufacturing scalability. Future research will focus on optimizing lymphodepleting regimens, mitigating toxicity, enhancing in vivo persistence, and combining ACT with other therapeutic agents. As clinical trials expand, ACT holds the potential to revolutionize sarcoma treatment by offering durable, targeted therapies for previously refractory disease.

EVs (extracellular vesicles) are phospholipid bilayer vesicles that can be released by both prokaryotic and eukaryotic cells in normal as well as altered physiological conditions. These vesicles also termed as signalosomes, possess a distinctive cargo comprising nucleic acids, proteins, lipids, and metabolites, enabling them to play a pivotal role in both local and long-distance intercellular communication. The composition, origin, and release of EVs can be influenced by different physiological conditions and a variety of stress factors, consequently affecting the contents carried within these vesicles. Therefore, identifying the modified contents of EVs can provide valuable insights into their functional role in stress-triggered communication. Particularly, this is important when EVs released from tumor microenvironment are investigated for their role in the development and dissemination of cancer. This review article emphasizes the importance of differential EV shedding and altered proteomic content in response to reduced oxygen concentration, altered levels of glucose and glutamine, pH variations, oxidative stress and Ca2+ ion concertation and it is subsequent effects on the behavior of recipient cells.

Approximately half of all cancers have p53 inactivating mutations, in addition to which most malignancies inactivate the p53 pathway by increasing p53 inhibitors, decreasing p53 activators, or inactivating p53 downstream targets. A growing number of researches have demonstrated that p53 can influence tumor progression through the tumor microenvironment (TME). TME is involved in the process of tumor development and metastasis and affects the clinical prognosis of patients. p53 participates in host immunity and engages in the immune landscape of the TME, but the specific mechanisms remain to be investigated. This review briefly explores the interactions between different states of p53 and TME components and their mechanisms, as well as their effects on tumor progression. To understand the progress of drug development and clinical studies related to p53 and tumor microenvironment.

Prostate cancer (PCa) ranks as the second leading cause of cancer-related deaths among men in the United States. Prostate-specific membrane antigen (PSMA) represents a well-established biomarker of PCa, and its levels correlate positively with the disease progression, culminating at the stage of metastatic castration-resistant prostate cancer. Due to its tissue-specific expression and cell surface localization, PSMA shows superior potential for precise imaging and therapy of PCa. Antibody-based immunotherapy targeting PSMA offers the promise of selectively engaging the host immune system with minimal off-target effects. Here we report on the design, expression, purification, and characterization of a bispecific engager, termed 5D3-CP33, that efficiently recruits macrophages to the vicinity of PSMA-positive cancer cells mediating PCa death. The engager was engineered by fusing the anti-PSMA 5D3 antibody fragment to a cyclic peptide 33 (CP33), selectively binding the Fc gamma receptor I (FcγRI/CD64) on the surface of phagocytes. Functional parts of the 5D3-CP33 engager revealed a nanomolar affinity for PSMA and FcγRI/CD64 with dissociation constants of KD =  3 nM and KD =  140 nM, respectively. At a concentration as low as 0.3 nM, the engager was found to trigger the production of reactive oxygen species by U937 monocytic cells in the presence of PSMA-positive cells. Moreover, flow cytometry analysis demonstrated antibody-dependent cell-mediated phagocytosis of PSMA-positive cancer cells by U937 monocytes when exposed to 0.15 nM 5D3-CP33. Our findings illustrate that 5D3-CP33 effectively and specifically activates monocytes upon PSMA-positive target engagement, resulting in the elimination of tumor cells. The 5D3-CP33 engager can thus serve as a promising lead for developing new immunotherapy tools for the efficient treatment of PCa.

In this study, the cytotoxic effects of pexidartinib (PLX), a tyrosine kinase inhibitor approved for tenosynovial giant cell tumor through inhibition of colony-stimulating factor 1 receptor (CSF1R), against A549 lung adenocarcinoma cells and Beas-2B healthy bronchial cells were investigated by in detailed in-vitro and in-silico studies. Through MTT assays, PLX demonstrated significant inhibition of A549 cell viability with IC50 values of 2.15 and 1.3 µM at 24 and 48 h, respectively, while having minimal effects on Beas-2B cells, with IC50 values of 36.2 and 9.3 µM. The high selectivity index indicates PLX's preferential action against cancerous cells. The mechanism of cell death induced by PLX was further explored using Annexin V/PI staining and flow cytometry, revealing that PLX primarily induces necrosis in A549 cells, with an increase in necrotic cell populations and reduced efficacy at higher concentrations. Western blot analysis showed an upregulation of necroptosis markers (RIP3 and pMLKL) in A549 cells, while apoptotic markers like Caspase-3 remained unchanged. In addition, wound healing assays demonstrated that PLX significantly inhibits A549 cell migration in a dose-dependent manner. Molecular docking studies identified key amino acids involved in PLX binding interactions with target proteins. RIPK1 showed the strongest binding affinity. MD simulations revealed that the PLX-VEGFR2 complex was the most stable. As conclusion, PLX, although approved for tenosynovial giant cell tumors, shows promising potential for lung adenocarcinoma treatment. It selectively inhibits cancer cell viability, induces necroptosis, and reduces cell migration. Its stronger binding to RIPK1 and VEGFR2 more than CSF1R.

Mucosal head and neck squamous cell carcinoma (HNSCC) is often diagnosed at an advanced stage, where the prognosis is poor due to the high rates of recurrence and metastasis. With approximately one million new cases projected in 2024, worldwide mortality of HNSCC is estimated to reach 50% of detected cases the same year. Patients with early-stage tumours showed a 50-60% five-year survival rate in the US. Immune checkpoint inhibitors (ICIs) have shown promising results in prolonging survival in a subset of patients with recurrent or metastatic disease. However, challenges remain, particularly the limited efficacy of PD-1/PD-L1 blockade therapies. PD-L1 protein expression has been shown to be limited in its predictive power for ICI therapies. Emerging evidence shows that intricate characterisation of the tumour microenvironment (TME) is fundamental to understand interacting cells. This study aims to bridge the gap in understanding the tumor microenvironment by identifying distinct spatial patterns of PD-1/PD-L1 interactions and their association with immunotherapy responses in head and neck squamous cell carcinoma (HNSCC).

In this study, we sought to apply a more nuanced approach to understanding cellular interactions by mapping PD-1/PD-L1 interactions across whole-slide HNSCC tissue samples collected prior to ICI therapy. We used a combination of spatial proteomics (Akoya Biosciences) and an in situ proximity ligation assay (isPLA, Navinci Diagnostics) to visualise PD-1/PD-L1 interactions across cell types and cellular neighbourhoods within the tumour TME.

Our findings indicate the existence of isPLA+ PD-1/PD-L1 interactions between macrophages/CD3 T cell-enriched neighbourhoods and tumour cells at the tumour-stroma boundaries in ICI-resistant tumours. The presence of these dense macrophage-tumour layers, which are either absent or dispersed in responders, indicates a barrier that may restrict immune cell infiltration and promote immune escape mechanisms. In contrast, responders had abundant B and T cell aggregates, predominantly around the tumour edges linked to enhanced immune responses to ICI therapy and better clinical outcomes.

This study highlights the utility of isPLA in detecting distinct tumour-immune interactions within the TME, offering new cellular interaction metrics for stratifying and optimising immunotherapy strategies.

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignant tumors with a high metastasis rate and a poor prognosis. ETS variant transcription factor 1 (ETV1) plays an important role in multiple malignancies. However, its function in ESCC progression and tumor microenvironment (TME) remains to be explored. In this study, we characterized the role of ETV1 in ESCC process and TME.

Gene expression and immune infiltration in ESCC samples from the Cancer Genome Atlas (TCGA) were analyzed. The expression of ETV1 in clinical samples was detected by real-time PCR, western blot and immunohistochemistry staining. Cell growth was detected by CCK-8 and colony formation assays. Macrophage phenotypes were determined using flow cytometry. Immunofluorescence double staining was used to detect the tumor-associated macrophage (TAM) infiltration. The tumor volume was recorded and weighed. Transcriptional activity was measured using dual-luciferase assay, chromatin immunoprecipitation (ChIP) assay and DNA pull-down assay.

In this study, through analysis of ESCC samples from TCGA database and the clinic, we noticed that ETV1 was highly expressed in ESCC tumor tissues and was associated with TAM infiltration. Overexpression of ETV1 promoted ESCC cell proliferation in vitro and xenograft tumor growth in nude mice, while ETV1 knockdown elicited the opposite effects. Furthermore, ETV1 upregulation in tumor tissues was found to drive M2 macrophage infiltration both in vitro (transwell assays) and in vivo (xenograft tumor models). C-C motif chemokine ligand 2 (CCL2), a key factor inducing M2 macrophage polarization, was also found to be elevated in ESCC tumor tissues. Mechanism study demonstrated that ETV1 facilitated M2 macrophage infiltration via the transcriptional modulation of CCL2. In addition, the cause of the changes in ETV1 activity and expression was investigated. The E2 small ubiquitin-like modifier (SUMO) binding enzyme UBC9 increased ETV1 activity and expression, indicating the presence of SUMO modification in ETV1.

Our data deciphered the mechanism of ETV1-mediated M2 macrophage infiltration in the TME of ESCC, which has important implications for the development of novel prognostic and therapeutic targets to optimize current therapies against ESCC.

Tumor-associated macrophages (TAMs) crucially contribute to lung cancer's advancement and escape from the immune system. TAMs, particularly the M2 phenotype, promote an immunosuppressive microenvironment, facilitating tumor growth and metastasis. The MEK-STAT3 signalling pathway is a critical mediator in this process, driving TAM reprogramming and contributing to lung cancer's resistance to treatment. Inhibiting the MEK and STAT3 pathways disrupts key cancer-promoting mechanisms, including immune evasion, angiogenesis, and metastasis. Preclinical studies have demonstrated the effectiveness of MEK inhibitors, such as trametinib and selumetinib, in synergistic therapies for NSCLC, particularly in modulating the tumor microenvironment. We analyse the present understanding of approaches that can transform TAMs via the inhibition of MEK-STAT3 with either solo or combined treatments in lung cancer therapy.

Neoplastic transformation reprograms tumor and surrounding host cell metabolism, increasing nutrient consumption and depletion in the tumor microenvironment. Tumors uptake nutrients from neighboring normal tissues or the bloodstream to meet energy and anabolic demands. Tumor-induced chronic inflammation, a high-energy process, also consumes nutrients to sustain its dysfunctional activities. These tumor-related metabolic and physiological changes, including chronic inflammation, negatively impact systemic metabolism and physiology. Furthermore, the adverse effects of antitumor therapy and tumor obstruction impair the endocrine, neural, and gastrointestinal systems, thereby confounding the systemic status of patients. These alterations result in decreased appetite, impaired nutrient absorption, inflammation, and shift from anabolic to catabolic metabolism. Consequently, cancer patients often suffer from malnutrition, which worsens prognosis and increases susceptibility to secondary adverse events. This review explores how neoplastic transformation affects tumor and microenvironment metabolism and inflammation, leading to poor prognosis, and discusses potential strategies and clinical interventions to improve patient outcomes.

Hepatocellular carcinoma (HCC) is a major global health issue characterized by poor prognosis and complex tumor biology. One of the critical components of the HCC tumor microenvironment (TME) is tumor-associated macrophages (TAMs), which play a pivotal role in modulating tumor growth, immune evasion, and metastasis. Macrophages are divided into two major subtypes: pro-inflammatory M1 and anti-inflammatory M2, both of which may exist in TME with altered function and proportion. The anti-inflammatory M2 macrophages are further subdivided into four distinct immune suppressive subsets. TAMs are generally counted as M2-like macrophages with altered immune suppressive functions that exert a significant influence on both cancer progression and the ability of tumors to escape immune surveillance. Their involvement in modulating immune responses via different mechanisms at the local and systemic levels has made them a key target for therapeutic interventions seeking to enhance treatment outcomes. How TAMs' depletion influences immune responses in cancer is the primary interest in cancer immunotherapies. The purpose of this review is to delve into the recent progress made in TAM-targeting therapies. We will explore the current theories, benefits, and challenges associated with TAMs' depletion or inhibition. The manuscript concludes with future directions and potential implications for clinical practice.

Immunotherapies have emerged as an effective treatment option for immune-related diseases, such as cancer and inflammatory diseases. However, variations in patient responsiveness limit the broad applicability and success of these immunotherapies. Noninvasive whole-body imaging of the immune status of individual patients during immunotherapy could enable the prediction and monitoring of the patient's response, resulting in more personalized treatments. In this study, we developed a nanobody-based immunotracer targeting CD163, a receptor specifically expressed on macrophages. This anti-CD163 immunotracer bound to human and mouse CD163 with high affinity and specificity without competing for ligand binding. Furthermore, the tracer showed no unwanted immune cell activation and was nonimmunogenic. Upon radiolabeling of the anti-CD163 immunotracer, specific imaging of CD163+ macrophages using micro-single-photon emission computerized tomography/computed tomography or micro-positron emission tomography/CT was performed. The anti-CD163 immunotracer was able to stratify immunotherapy responders from nonresponders (NR) by visualizing differences in the intratumoral CD163+ TAM distribution in Lewis lung carcinoma-ovalbumin tumor-bearing mice receiving an anti-programmed cell death protein-1 (PD-1)/CSF1R combination treatment. Immunotherapy-responding mice showed a more homogeneous distribution of the PET signal in the middle of the tumor, while CD163+ TAMs were located at the tumor periphery in NR. As such, visualization of CD163+ TAM distribution in the tumor microenvironment could allow a prediction or follow-up of therapy response. Altogether, this study describes an immunotracer, specific for CD163+ macrophages, that allows same-day imaging and follow-up of these immune cells in the tumor microenvironment, providing a good basis for the prediction and follow-up of immunotherapy responses in cancer patients.

Macrophages, the most abundant cells that participate in tumour progression, are the subject of a number of anticancer therapy approaches. Our previous results revealed that an extract of the fungus Coriolus versicolor (CV) has anti-cancer and immunomodulatory properties. The aim of the present study was to investigate whether CV extract-treated triple-negative breast cancer (TNBC) cells can release factors that can reprogram macrophages from pro-tumourigenic to anti-cancer subtypes. RAW 264.7 macrophages were cultured in a conditioned medium (CM) from non-treated 4T1 breast cancer cells (CM-NT) or CV extract-stimulated cells (CM-CV). After treatment, the following macrophage properties were evaluated: cell viability; M1/M2 phenotype (enzyme activities: iNOS and arginase 1; and expression of CD molecules: CD80 and CD163); cytokine concentrations: IL-6, TNF-α, IL-10, TGF-β, MCP-1 and VEGF; migration level; and ROS production. The results revealed that, compared with normal cells, TNBC cells stimulated with CV extract create a microenvironment that promotes a decrease in macrophage viability and migration, intracellular ROS production, and pro-angiogenic cytokine production (VEGF and MCP-1). Moreover, CM-CV decreased the expression of M2 macrophage markers (arginase 1 and CD163; IL-10 and TGF-β) but upregulated the expression of M1 cell markers (iNOS and CD80; IL-6 and TNF-α). We concluded that CV extract modifies the tumour microenvironment and changes macrophage polarisation toward functioning as an anti-tumour agent. Therefore, it is promising to use in the treatment of TNBC-associated macrophages.

Colon cancer ranks second in overall cancer-related deaths and poses a serious risk to human life and health. In recent years, exosomes are believed to play an important and significant role in cancer, especially tumor-derived exosomes (TDEs). Previous studies have highlighted the pivotal role of exosomes in tumor development, owing to their ability to mediate communication between tumor cells and macrophages, induce macrophage M2 polarization, and facilitate the progression of tumorigenesis. In this study, we revealed that colon cancer-derived exosomes promoted M2-like macrophage polarization. Moreover, exosome-induced M2-like macrophages, in turn, promoted the proliferation, migration, and invasion abilities of colon cancer cells. Specifically, CT26- and HCT116-derived exosomes led to the activation of AKT, ERK, and STAT3/6 signaling pathways in THP-1(Mφ) cells. Furthermore, our findings showed that colon cancer-derived exosomes secreted lncXIST to sponge miR-17-5p, which, in turn, promoted the expression of PDGFRA, a common gene found in all three signaling pathways, to facilitate M2-like macrophage polarization. Dual-luciferase reporter assays confirmed the binding relationship between lncXIST and miR-17-5p, as well as miR-17-5p and PDGFRA. Collectively, our results highlight the novel role of lncXIST in facilitating macrophage polarization by sponging miR-17-5p and regulating PDGFRA expression.

The genesis and progression of tumors are multifaceted processes influenced by genetic mutations within the tumor cells and the dynamic interplay with their surrounding milieu, which incessantly impacts the course of cancer. The tumor microenvironment (TME) is a complex and dynamic entity that encompasses not only the tumor cells but also an array of non-cancerous cells, signaling molecules, and the extracellular matrix. This intricate network is crucial in tumor progression, metastasis, and response to treatments. The TME is populated by diverse cell types, including immune cells, fibroblasts, endothelial cells, alongside cytokines and growth factors, all of which play roles in either suppressing or fostering tumor growth. Grasping the nuances of the interactions within the TME is vital for the advancement of targeted cancer therapies. Consequently, a thorough understanding of the alterations of TME and the identification of upstream regulatory targets have emerged as a research priority. NF-κB transcription factors, central to inflammation and innate immunity, are increasingly recognized for their significant role in cancer onset and progression. This review emphasizes the crucial influence of the NF-κB signaling pathway within the TME, underscoring its roles in the development and advancement of cancer. By examining the interactions between NF-κB and various components of the TME, targeting the NF-κB pathway appears as a promising cancer treatment approach.

Macrophages play crucial roles in the tumor microenvironment (TME), exerting diverse functions ranging from promoting tumor growth and metastasis to orchestrating anti-tumor immune responses. Their plasticity allows them to adopt distinct activation states, often called M1-like (pro-inflammatory) and M2-like (anti-inflammatory or pro-tumoral), significantly influencing tumor progression and response to therapy. Harnessing the potential of macrophages in cancer immunotherapy has emerged as a promising strategy, with increasing interest in targeting these cells directly or modulating their functions within the TME. This review explores the intricate interplay between macrophages, the TME, and immunotherapeutic approaches. We discuss the dynamic phenotypic and functional heterogeneity of tumor-associated macrophages (TAMs), their impact on disease progression, and the mechanisms underlying their response to immunotherapy. Furthermore, we highlight recent advancements in macrophage-based immunotherapeutic strategies, including macrophage-targeting agents, adoptive cell transfer, and engineering approaches. Understanding the complex crosstalk between macrophages and the TME is essential for developing effective immunotherapeutic interventions that exploit the immunomodulatory functions of macrophages to enhance anti-tumor immunity and improve clinical outcomes for cancer patients.

Hepatocellular carcinoma (HCC) is a deadly cancer with a high global mortality rate, and the downregulation of GATA binding protein 4 (GATA4) has been implicated in HCC progression. In this study, we investigated the role of GATA4 in shaping the immune landscape of HCC.

HCC tumor samples were classified into "low" or "normal/high" based on GATA4 RNA expression relative to adjacent non-tumor liver tissues. The immune landscapes of GATA4-low and GATA4-normal/high tumors were analyzed using cytometry by time-of-flight, bulk/spatial transcriptomic analyses and validated by multiplex immunofluorescence.

GATA4-low tumors displayed enrichment in exhausted programmed cell death protein 1+ T cells, immunosuppressive regulatory T cells, myeloid-derived suppressor cells, and macrophages, highlighting the impact of GATA4 downregulation on immunosuppression. Spatial and bulk transcriptomic analyses revealed a negative correlation between GATA4 and C-C Motif Chemokine Ligand 20 (CCL20) expression in HCC. Overexpressing GATA4 confirmed CCL20 as a downstream target, contributing to an immunosuppressive tumor microenvironment, as evidenced by increased regulatory T cells and myeloid-derived suppressor cells in CCL20-high tumors. Lastly, the reduced expression of GATA4 and higher expression of CCL20 were associated with poorer overall survival in patients with HCC, implicating their roles in tumor progression.

Our study reveals that GATA4 downregulation contributes to an immunosuppressive microenvironment, driven by CCL20-mediated enrichment of regulatory T cells and myeloid-derived suppressor cells in HCC. These findings underscore the critical role of GATA4 reduction in promoting immunosuppression and HCC progression.

Alternatively activated macrophage (M2) polarization can result in one of four subtypes based on cytokines and signaling pathways associated with macrophage activation: M2a, M2b, M2c, and M2d macrophages. The majority of M2 subtypes are anti-inflammatory and pro-angiogenic, secreting growth factors (VEGF, PDGF) and matrix metalloproteinases (MMP2, MMP9) which boost tumor growth, metastasis, and invasion. M2-polarized macrophages are associated with immune suppressor cells harboring Myeloid derived suppressor cells, Regulatory T cells (Tregs), Regulatory B cells as well as alternatively activated (N2) neutrophils. Treg cells selectively support the metabolic stability, mitochondrial integrity, and survival rate of M2-like TAMs in an indirect environment. Also, the contribution of Breg cells influences macrophage polarization towards the M2 direction. TAM is activated when TAN levels in the tumor microenvironment are insufficient or vice versa, suggesting that macrophage and its polarization are fine-tuned. Understanding the functions of immune suppressive cells, mediators, and signaling pathways involved with M2 polarization will allow us to identify potential strategies for targeting the TAM repolarization phenotype for innovative immunotherapy approaches. In this review, we have highlighted the critical factors for M2 macrophage polarization, differential cytokine/chemokine profiles of M1 and M2 macrophage subtypes, and other immune cells' impact on the polarization within the immunosuppressive niche.

Cancer treatment has long been fraught with challenges, including drug resistance, metastasis, and recurrence, making it one of the most difficult diseases to treat effectively. Traditional therapeutic approaches often fall short due to their inability to target cancer stem cells and the complex genetic and epigenetic landscape of tumors. In recent years, cancer immunotherapy has revolutionized the field, offering new hope and viable alternatives to conventional treatments. A particularly promising area of research focuses on non-coding RNAs (ncRNAs), especially long non-coding RNAs (lncRNAs), and their role in cancer resistance and the modulation of signaling pathways. To address these challenges, we performed a comprehensive review of recent studies on lncRNAs and their impact on cancer immunotherapy. Our review highlights the crucial roles that lncRNAs play in affecting both innate and adaptive immunity, thereby influencing the outcomes of cancer treatments. Key observations from our review indicate that lncRNAs can modify the tumor immune microenvironment, enhance immune cell infiltration, and regulate cytokine production, all of which contribute to tumor growth and resistance to therapies. These insights suggest that lncRNAs could serve as potential targets for precision medicine, opening up new avenues for developing more effective cancer immunotherapies. By compiling recent research on lncRNAs across various cancers, this review aims to shed light on their mechanisms within the tumor immune microenvironment.

Due to the lack of treatment options, there remains a need to advance new therapeutics in hepatocellular carcinoma (HCC). The traditional approach moves from initial molecular discovery through animal models to human trials to advance novel systemic therapies that improve treatment outcomes for patients with cancer. Computational methods that simulate tumors mathematically to describe cellular and molecular interactions are emerging as promising tools to simulate the impact of therapy entirely in silico, potentially greatly accelerating delivery of new therapeutics to patients. To facilitate the design of dosing regimens and identification of potential biomarkers for immunotherapy, we developed a new computational model to track tumor progression at the organ scale while capturing the spatial heterogeneity of the tumor in HCC. This computational model of spatial quantitative systems pharmacology was designed to simulate the effects of combination immunotherapy. The model was initiated using literature-derived parameter values and fitted to the specifics of HCC. Model validation was done through comparison with spatial multiomics data from a neoadjuvant HCC clinical trial combining anti-PD1 immunotherapy and a multitargeted tyrosine kinase inhibitor cabozantinib. Validation using spatial proteomics data from imaging mass cytometry demonstrated that closer proximity between CD8 T cells and macrophages correlated with nonresponse. We also compared the model output with Visium spatial transcriptomics profiling of samples from posttreatment tumor resections in the clinical trial and from another independent study of anti-PD1 monotherapy. Spatial transcriptomics data confirmed simulation results, suggesting the importance of spatial patterns of tumor vasculature and TGFβ in tumor and immune cell interactions. Our findings demonstrate that incorporating mathematical modeling and computer simulations with high-throughput spatial multiomics data provides a novel approach for patient outcome prediction and biomarker discovery. Significance: Incorporating mathematical modeling and computer simulations with high-throughput spatial multiomics data provides an effective approach for patient outcome prediction and biomarker discovery.

Cancer remains a significant risk to human health. Nanomedicine is a new multidisciplinary field that is garnering a lot of interest and investigation. Nanomedicine shows great potential for cancer diagnosis and treatment. Specifically engineered nanoparticles can be employed as contrast agents in cancer diagnostics to enable high sensitivity and high-resolution tumor detection by imaging examinations. Novel approaches for tumor labeling and detection are also made possible by the use of nanoprobes and nanobiosensors. The achievement of targeted medication delivery in cancer therapy can be accomplished through the rational design and manufacture of nanodrug carriers. Nanoparticles have the capability to effectively transport medications or gene fragments to tumor tissues via passive or active targeting processes, thus enhancing treatment outcomes while minimizing harm to healthy tissues. Simultaneously, nanoparticles can be employed in the context of radiation sensitization and photothermal therapy to enhance the therapeutic efficacy of malignant tumors. This review presents a literature overview and summary of how nanotechnology is used in the diagnosis and treatment of malignant tumors. According to oncological diseases originating from different systems of the body and combining the pathophysiological features of cancers at different sites, we review the most recent developments in nanotechnology applications. Finally, we briefly discuss the prospects and challenges of nanotechnology in cancer.

Malignant tumor, one of the most threatening diseases to human health, has been comprehensively treated with surgery, radiotherapy, chemotherapy and targeted therapy, but the prognosis has not always been ideal. In the past decade, immunotherapy has shown increased efficacy in tumor treatment; however, for immunotherapy to achieve its fullest potential, obstacles are to be conquered, among which tumor microenvironment (TME) has been widely investigated. In remodeling the tumor immune microenvironment to inhibit tumor progression, macrophages, as the most abundant innate immune population, play an irreplaceable role in the immune response. Therefore, how to remodel TME and alter the recruitment and polarization status of tumor-associated macrophages (TAM) has been of wide interest. In this context, nanoparticles, photodynamic therapy and other therapeutic approaches capable of affecting macrophage polarization have emerged. In this paper, we categorize and organize the existing means and methods for reprogramming TAM to provide ideas for clinical application of novel tumor-related therapies.

Immunotherapy has become an important part of the oncotherapy arsenal. Its applicability in various cancer types is impressive, as well as its use of endogenous mechanisms to achieve desired ends. However, off-target or on-target-off-tumor toxicity, limited activity, lack of control in combination treatments and, especially for solid tumors, low local accumulation, have collectively limited clinical use thereof. These limitations are partially alleviated by delivery systems. Lipid-based nanoparticles (NPs) have emerged as revolutionary carriers due to favorable physicochemical characteristics, with specific applications and strengths particularly useful in immunotherapeutic agent delivery. The aim of this review is to highlight the challenges faced by immunotherapy and how lipid-based NPs have been, and may be further utilized to address such challenges. We discuss recent fundamental and clinical applications of NPs in a range of areas and provide a detailed discussion of the main obstacles in immune checkpoint inhibition therapies, adoptive cellular therapies, and cytokine therapies. We highlight how lipid-based nanosystems could address these through either delivery, direct modulation of the immune system, or targeting of the immunosuppressive tumor microenvironment. We explore advanced and emerging liposomal and lipid nanoparticle (LNP) systems for nucleic acid delivery, intrinsic and extrinsic stimulus-responsive formulations, and biomimetic lipid-based nanosystems in immunotherapy. Finally, we discuss the key challenges relating to the clinical use of lipid-based NP immunotherapies, suggesting future research directions for the near term to realize the potential of these innovative lipid-based nanosystems, as they become the crucial steppingstone towards the necessary enhancement of the efficacy of immunotherapy.

Tumor-associated macrophages play a crucial role in the tumor microenvironment. Tripartite motif 59 (TRIM59), a member of the tripartite motif (TRIM) family, is known to be associated with immunological diseases and macrophage activation. The functional and molecular mechanisms by which TRIM59 affects the occurrence and development of colorectal cancer (CRC) through macrophages are still not well understood. To address this, we generated macrophage-specific TRIM59 conditional knockout mice and utilized these mice to establish colitis-associated cancer and MC38 transplanted CRC models for further investigation. We found that the deficiency of TRIM59 in macrophages inhibited colorectal tumorigenesis in mice. This tumor-suppressive effect was achieved by promoting the activation of M1 macrophages via STAT1 signaling pathway. Further mechanistic studies revealed that TRIM59 could regulate macrophage polarization by ubiquitinating and degrading STAT1. These findings provide evidence that TRIM59 deficiency promotes M1 macrophage activation and inhibits CRC through the STAT1 signaling pathway, suggesting that the TRIM59/STAT1 signaling pathway may be a promising target for CRC.

The tumor microenvironment (TME) plays a crucial role in the progression, invasion, and metastasis of cervical carcinoma (CC). Tumor-associated macrophages (TAMs) are significant components of the CC TME, but studies on their correlation with CC progression are still controversial. This study aimed to investigate the relationship between TAM infiltration, the STAT3/NF-κB signaling pathway, and Overall Survival (OS) in CC patients.

In a retrospective study, 691 CC patients who had received a definitive histopathologic diagnosis of CC scored by the FIGO staging system and not undergone preoperative treatment were selected from a database. The effect of TAM infiltration on tumor progression biomarkers using Tissue Microarray (TMA) and immunohistochemistry was evaluated. Furthermore, the impact of the expression of these biomarkers and clinical-pathological parameters on recurrence-free (RF) and OS using Kaplan-Meier and multivariable Cox regression methods was also analyzed.

High stromal CD163 + 204 + TAMs density and via STAT3 and NF-κB pathways was relevant to the expression of E-cadherin, Vimentin, MMP9, VEGFα, Bcl-2, Ki-67, CD25, MIF, FOXP3, and IL-17 (all p < 0.0001). In addition, elevated TNM staging IV had a strong association correlation with STAT3 and NF-κB pathways (p < 0.0001), CD25 (p < 0.001), VEGFα (p < 0.001), MIF (p < 0.0001), and Ki-67 (p < 0.0001). On the other hand, overall and recurrence survival was shown to be strongly influenced by the expression of SNAIL (HR = 1.52), E-cadherin (HR = 1.78), and Ki-67 (HR = 1.44).

M2-TAM and via STAT3/NF-κB pathways had a strong effect on CC tumor progression which reverberated in the severity of clinicopathological findings, becoming an important factor of poor prognosis.

Improving immunotherapy efficacy for EGFR-negative lung adenocarcinoma (LUAD) patients remains a critical challenge, and the therapeutic effect of immunotherapy is largely determined by the tumor microenvironment (TME). Tumor-associated macrophages (TAMs) are the top-ranked immune infiltrating cells in the TME, and M2-TAMs exert potent roles in tumor promotion and chemotherapy resistance. An M2-TAM-based prognostic signature was constructed by integrative analysis of single-cell RNA-seq (scRNA-seq) and bulk RNA-seq data to reveal the immune landscape and select drugs in EGFR-negative LUAD.

M2-TAM-based biomarkers were obtained from the intersection of bulk RNA-seq data and scRNA-seq data. After consensus clustering of EGFR-negative LUAD into different clusters based on M2-TAM-based genes, we compared the prognosis, clinical features, estimate scores, immune infiltration, and checkpoint genes among the clusters. Next, we combined univariate Cox and LASSO regression analyses to establish an M2-TAM-based prognostic signature.

CCL20, HLA-DMA, HLA-DRB5, KLF4, and TMSB4X were verified as prognostic M2-like TAM-related genes by univariate Cox and LASSO regression analyses. IPS and TMB analyses revealed that the high-risk group responded better to common immunotherapy.

The study shows the potential of the M2-like TAM-related gene signature in EGFR-negative LUAD, explores the immune landscape based on M2-like TAM-related genes, and predict immunotherapy response of patients with EGFR-negative LUAD, providing a new insight for individualized treatment.

In the context of hepatocellular carcinoma (HCC), tumor-associated macrophages (TAMs) are pivotal for the immunosuppressive nature of the tumor microenvironment (TME). This investigation delves into the functional transformations of TAMs within the TME by leveraging single-cell transcriptomics to pinpoint critical genes influencing TAM subset polarization.

We procured single-cell and bulk transcriptomic data from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA), implementing quality assurance, dimensional reduction, clustering, and annotation on the single-cell sequencing data. To examine cellular interactions, CellChat was utilized, while single-cell regulatory network inference and clustering (SCENIC) was applied to deduce transcription factors (TFs) and their associated targets. Through gene enrichment, survival, and immune infiltration correlation analyses, we sought to pinpoint and validate influential genes. A TAM model under HCC conditions was then established to confirm the expression levels of these key genes.

Our analysis encompassed 74,742 cells and 23,110 genes. Through postdimensional reduction and clustering, we identified seven distinct cell types and nine TAM subtypes. Analysis via CellChat highlighted a predominance of M2-phenotype-inclined TAM subsets within the tumor's core. SCENIC pinpointed the transcription factor PRDM1 and its target genes as pivotal in this region. Further analysis indicated these genes' involvement in macrophage polarization. Employing trajectory analysis, survival analysis, and immune infiltration correlation, we scrutinized and validated genes likely directing M2 polarization. Experimental validation confirmed PRDM1's heightened expression in TAMs conditioned by HCC.

Our findings suggest the PRDM1 gene is a key regulator of M2 macrophage polarization, contributing to the immunosuppressive TME in HCC.

In most cancers, tumor hypoxia downregulates the expression of C-C motif chemokine 2 (CCL2), and this downregulation has been implicated in monocyte infiltration and tumor progression; however, the molecular mechanism is not yet clear. We compared noncancerous and lung-adenocarcinoma human samples for hypoxia-inducible factor 1-alpha (HIF-1A), microRNA-210-3p (mir-210-3p), and CCL2 levels. Mechanistic studies were performed on lung adenocarcinoma cell lines and 3D tumor spheroids to understand the role of hypoxia-induced miR-210-3p in the regulation of CCL2 expression and macrophage polarization. HIF-1Α stabilization increases miR-210-3p levels in lung adenocarcinoma and impairs monocyte infiltration by inhibiting CCL2 expression. Mechanistically, miR-210-3p directly binds to the 3'untranslated region (UTR) of CCL2 mRNA and silences it. Suppressing miR-210-3p substantially downregulates the effect of hypoxia on CCL2 expression. Monocyte migration is significantly hampered in miR-210-3p mimic-transfected HIF-1A silenced cancer cells. In contrast, inhibition of miR-210-3p in HIF-1A-overexpressed cells markedly restored monocyte migration, highlighting a direct link between the miR-210-3p level and tumor monocyte burden. Moreover, miR-210-3p inhibition in 3D tumor spheroids promotes monocyte recruitment and skewing towards an antitumor M1 phenotype. Anti-hsa-miR-210-3p-locked nucleic acid (LNA) delivery in a lung tumor xenograft zebrafish model caused tumor regression, suggesting that miR-210-3p could be a promising target for immunomodulatory therapeutic strategies against lung adenocarcinoma.