Macrophage diversity enhances tumor progression and metastasis. Cell. 2010;141:39-51. [PMID: 20371344 DOI: 10.1016/j.cell.2010.03.014]

Immune mediated support of metastasis: Implication for bone invasion

Bone is a common organ affected by metastasis in various advanced cancers, including lung, breast, prostate, colorectal, and melanoma. Once a patient is diagnosed with bone metastasis, the patient's quality of life and overall survival are significantly reduced owing to a wide range of morbidities and the increasing difficulty of treatment. Many studies have shown that bone metastasis is closely related to bone microenvironment, especially bone immune microenvironment. However, the effects of various immune cells in the bone microenvironment on bone metastasis remain unclear. Here, we described the changes in various immune cells during bone metastasis and discussed their related mechanisms. Osteoblasts, adipocytes, and other non-immune cells closely related to bone metastasis were also included. This review also summarized the existing treatment methods and potential therapeutic targets, and provided insights for future studies of cancer bone metastasis.

Genetic Engineering Bacillus thuringiensis Enable Melanin Biosynthesis for Anti-Tumor and Anti-Inflammation

Collaboration between cancer treatment and inflammation management has emerged as an integral facet of comprehensive cancer care. Nevertheless, the development of interventions concurrently targeting both inflammation and cancer has encountered significant challenges stemming from various external factors. Herein, a bioactive agent synthesized by genetically engineering melanin-producing Bacillus thuringiensis (B. thuringiensis) bacteria, simultaneously achieves eco-friendly photothermal agent and efficient reactive oxygen/nitrogen species (RONS) scavenger benefits, perfectly tackling present toughies from inflammation to cancer therapies. The biologically derived melanin exhibits exceptional photothermal-conversion performance, facilitating potent photonic hyperthermia that effectively eradicates tumor cells and tissues, thereby impeding tumor growth. Additionally, the RONS-scavenging properties of melanin produced by B. thuringiensis bacteria contribute to inflammation reduction, augmenting the efficacy of photothermal tumor repression. This study presents a representative paradigm of genetic engineering in B. thuringiensis bacteria to produce functional agents tailored for diverse biomedical applications, encompassing inflammation and cancer therapy.

Biomaterials-Boosted Immunotherapy for Osteosarcoma

Osteosarcoma (OS) is a primary malignant bone tumor that emanates from mesenchymal cells, commonly found in the epiphyseal end of long bones. The highly recurrent and metastatic nature of OS poses significant challenges to the efficacy of treatment and negatively affects patient prognosis. Currently, available clinical treatment strategies primarily focus on maximizing tumor resection and reducing localized symptoms rather than the complete eradication of malignant tumor cells to achieve ideal outcomes. The biomaterials-boosted immunotherapy for OS is characterized by high effectiveness and a favorable safety profile. This therapeutic approach manipulates the tumor microenvironments at the cellular and molecular levels to impede tumor progression. This review delves into the mechanisms underlying the treatment of OS, emphasizing biomaterials-enhanced tumor immunity. Moreover, it summarizes the immune cell phenotype and tumor microenvironment regulation, along with the ability of immune checkpoint blockade to activate the autoimmune system. Gaining a profound comprehension of biomaterials-boosted OS immunotherapy is imperative to explore more efficacious immunotherapy protocols and treatment options in this setting.

ROS: A "booster" for chronic inflammation and tumor metastasis

Reactive oxygen species (ROS) are a group of highly active molecules produced by normal cellular metabolism and play a crucial role in the human body. In recent years, researchers have increasingly discovered that ROS plays a vital role in the progression of chronic inflammation and tumor metastasis. The inflammatory tumor microenvironment established by chronic inflammation can induce ROS production through inflammatory cells. ROS can then directly damage DNA or indirectly activate cellular signaling pathways to promote tumor metastasis and development, including breast cancer, lung cancer, liver cancer, colorectal cancer, and so on. This review aims to elucidate the relationship between ROS, chronic inflammation, and tumor metastasis, explaining how chronic inflammation can induce tumor metastasis and how ROS can contribute to the evolution of chronic inflammation toward tumor metastasis. Interestingly, ROS can have a "double-edged sword" effect, promoting tumor metastasis in some cases and inhibiting it in others. This article also highlights the potential applications of ROS in inhibiting tumor metastasis and enhancing the precision of tumor-targeted therapy. Combining ROS with nanomaterials strategies may be a promising approach to enhance the efficacy of tumor treatment.

In vivo monitoring of leukemia-niche interactions in a zebrafish xenograft model

Acute lymphoblastic leukemia (ALL) is the most common type of malignancy in children. ALL prognosis after initial diagnosis is generally good; however, patients suffering from relapse have a poor outcome. The tumor microenvironment is recognized as an important contributor to relapse, yet the cell-cell interactions involved are complex and difficult to study in traditional experimental models. In the present study, we established an innovative larval zebrafish xenotransplantation model, that allows the analysis of leukemic cells (LCs) within an orthotopic niche using time-lapse microscopic and flow cytometric approaches. LCs homed, engrafted and proliferated within the hematopoietic niche at the time of transplant, the caudal hematopoietic tissue (CHT). A specific dissemination pattern of LCs within the CHT was recorded, as they extravasated over time and formed clusters close to the dorsal aorta. Interactions of LCs with macrophages and endothelial cells could be quantitatively characterized. This zebrafish model will allow the quantitative analysis of LCs in a functional and complex microenvironment, to study mechanisms of niche mediated leukemogenesis, leukemia maintenance and relapse development.

M2 macrophage-derived lncRNA NORAD in EVs promotes NSCLC progression via miR-520g-3p/SMIM22/GALE axis

Non-small cell lung cancer (NSCLC) constitutes the majority of lung cancer cases, accounting for over 80%. RNAs in EVs play a pivotal role in various biological and pathological processes mediated by extracellular vesicle (EV). Long non-coding RNAs (lncRNAs) are widely associated with cancer-related functions, including cell proliferation, migration, invasion, and drug resistance. Tumor-associated macrophages are recognized as pivotal contributors to tumorigenesis. Given these insights, this study aims to uncover the impact of lncRNA NORAD in EVs derived from M2 macrophages in NSCLC cell lines and xenograft mouse models of NSCLC. EVs were meticulously isolated and verified based on their morphology and specific biomarkers. The interaction between lncRNA NORAD and SMIM22 was investigated using immunoprecipitation. The influence of SMIM22/GALE or lncRNA NORAD in EVs on glycolysis was assessed in NSCLC cell lines. Additionally, we evaluated the effects of M2 macrophage-derived lncRNA NORAD in EVs on cell proliferation and apoptosis through colony formation and flow cytometry assays. Furthermore, the impact of M2 macrophage-derived lncRNA NORAD in EVs on tumor growth was confirmed using xenograft tumor animal models. The results underscored the potential role of M2 macrophage-derived lncRNA NORAD in EVs in NSCLC. SMIM22/GALE promoted glycolysis and the proliferation of NSCLC cells. Furthermore, lncRNA NORAD in EVs targeted SMIM22 and miR-520g-3p in NSCLC cells. Notably, lncRNA NORAD in EVs promoted the proliferation of NSCLC cells and facilitated NSCLC tumor growth through the miR-520g-3p axis. In conclusion, M2 macrophage-derived lncRNA NORAD in EVs promotes NSCLC progression through the miR-520g-3p/SMIM22/GALE axis.

Improving the efficacy of immunotherapy for colorectal cancer: Targeting tumor microenvironment-associated immunosuppressive cells

Currently, immune checkpoint inhibitors (ICIs) have changed the treatment paradigm for many malignant tumors. As the most common digestive tract malignancy, colorectal cancer (CRC) shows a good response to ICIs only in a small subset of patients with MSI-H/dMMR CRC. In contrast, patients with MSS/pMMR CRC show minimal response to ICIs. The results of the REGONIVO study suggest that targeting the tumor microenvironment (TME) to improve immunotherapy outcomes in MSS/pMMR CRC patients is a feasible strategy. Therefore, this article focuses on exploring the feasibility of targeting the TME to enhance immunotherapy outcomes in CRC, collecting recent basic research on targeting the TME to enhance immunotherapy outcomes in CRC and analyzing ongoing clinical trials to provide a theoretical basis and future research directions for improving immunotherapy outcomes in MSS/pMMR CRC.

Knockdown of HM13 Inhibits Metastasis, Proliferation, and M2 Macrophage Polarization of Non-small Cell Lung Cancer Cells by Suppressing the JAK2/STAT3 Signaling Pathway

An upregulated histocompatibility minor 13 (HM13) has been studied in various tumors, yet the exact mechanism of HM13 in non-small cell lung cancer (NSCLC) is unclear. In view of same, the present study investigates crucial role and action mechanism of HM13 in human NSCLC. HM13 expression was higher in NSCLC tissue and cells through the Western blotting technique along with qRT-PCR. As per data from The Cancer Genome Atlas (TCGA), NSCLC patients having high HM13 expression show lower overall survival. 5-ethynyl-2-deoxyuridine (EdU), Cell Counting Kit-8 (CCK-8), and transwell tests were assessed for NSCLC cell growth, and invasion, and we found that silencing of HM13 inhibited the NSCLC cell proliferation, invasion. Additionally, to investigate the effects of HM13 on THP-1 macrophage polarization, a co-culture model of NSCLC and THP-1 macrophages were used. The CD206 + macrophages were examined using flow cytometry. As the markers of M2 macrophage, the mRNA levels of IL-10 and TGF-β of THP-1 cells were also detected by qRT-PCR. Knockdown of HM13 could inhibit the M2 polarization. Further experiments demonstrated that downregulated HM13 could inhibit the JAK2/STAT3 signaling pathway. RO8191 (activator of JAK/STAT3 pathway) influenced the invasion, proliferation, and expression of JAK2/STAT3 signaling pathway and Epithelial-mesenchymal transition (EMT) markers induced by HM13 silencing. HM13 knockdown also inhibited the tumor growth in vivo by xenograft nude mouse model. By inhibiting JAK2/STAT3 signaling pathway, HM13 knockdown inhibited the NSCLC cell proliferation, metastasis tumor growth, and tumor-associated macrophage M2 polarization. In NSCLC, HM13 could be a therapeutic target to treat the NSCLC.

Apoptosis-Cell Cycle-Autophagy Molecular Mechanisms Network in Heterogeneous Aggressive Phenotype Prostate Hyperplasia Primary Cell Cultures Have a Prognostic Role

Our study highlights the apoptosis, cell cycle, DNA ploidy, and autophagy molecular mechanisms network to identify prostate pathogenesis and its prognostic role. Caspase 3/7 expressions, cell cycle, adhesion glycoproteins, autophagy, nuclear shrinkage, and oxidative stress by flow-cytometry analysis are used to study the BPH microenvironment's heterogeneity. A high late apoptosis expression by caspases 3/7 activity represents an unfavorable prognostic biomarker, a dependent predictor factor for cell adhesion, growth inhibition by arrest in the G2/M phase, and oxidative stress processes network. The heterogeneous aggressive phenotype prostate adenoma primary cell cultures present a high S-phase category (>12%), with an increased risk of death or recurrence due to aneuploid status presence, representing an unfavorable prognostic biomarker, a dependent predictor factor for caspase 3/7 activity (late apoptosis and necrosis), and cell growth inhibition (G2/M arrest)-linked mechanisms. Increased integrin levels in heterogenous BPH cultures suggest epithelial-mesenchymal transition (EMT) that maintains an aggressive phenotype by escaping cell apoptosis, leading to the cell proliferation necessary in prostate cancer (PCa) development. As predictor biomarkers, the biological mechanisms network involved in apoptosis, the cell cycle, and autophagy help to establish patient prognostic survival or target cancer therapy development.

The complex role of macrophages in pancreatic cancer tumor microenvironment: a review on cancer progression and potential therapeutic targets

Pancreatic cancer (PC) is one of the deadliest cancers worldwide with low survival rates and poor outcomes. The treatment landscape for PC is fraught with obstacles, including drug resistance, lack of effective targeted therapies and the immunosuppressive tumor microenvironment (TME). The resistance of PC to existing immunotherapies highlights the need for innovative approaches, with the TME emerging as a promising therapeutic target. The recent advancements in understanding the role of macrophages, this context highlight their significant impact on tumor development and progression. There are two important types of macrophages: M1 and M2, which play critical roles in the TME. Therapeutics strategies including, depletion of tumor-associated macrophages (TAMs), reprogramming TAMs to promote anti-tumor activity, and targeting macrophage recruitment can lead to promising outcomes. Targeting macrophage-related pathways may offer novel strategies for modulating immune responses, inhibiting angiogenesis, and overcoming resistance to chemotherapy in PC treatment.

Ovarian cancer derived extracellular vesicles promote the cancer progression and angiogenesis by mediating M2 macrophages polarization

BACKGROUND

Extracellular vesicles (EVs) are mediators between cancer cells and other types of cells, such as tumor-associated macrophages (TAMs), in the tumor microenvironment. EVs can remodel the tumor microenvironment and regulate tumor progression. However, the underlying molecular mechanism of these interactions remains unclear.

METHODS

First, we explored the effect of TAMs on the survival prognosis of patients with ovarian cancer. Next, we isolated EVs derived from ovarian cancer cells (OV-EVs) through ultracentrifugation and analyzed the capacity of OV-EVs to regulate macrophage polarization in ovarian tumors and in whole peripheral blood. Moreover, we explored the roles of OV-EVs-induced macrophages in tumor progression through in vitro and in vivo assays.

RESULTS

OV-EVs were encapsulated by macrophages and induced the polarization of macrophages toward the M2 phenotype. Moreover, OV-EVs-induced M2 macrophages promoted angiogenesis and cancer progression both in vitro and in vivo. In addition, OV-EVs-induced macrophages increased the expression level of VEGF and increased the expression level of VEGFR in tumors, which resulted in angiogenesis in ovarian cancer.

CONCLUSIONS

The present study demonstrated that OV-EVs induce M2 polarization in macrophages and promote the progression of ovarian cancer. This study provides novel insight into the mechanism of ovarian cancer progression.

Integrated Analysis of Phagocytic and Immunomodulatory Markers in Cervical Cancer Reveals Constellations of Potential Prognostic Relevance

Despite improvements in vaccination, screening, and treatment, cervical cancer (CC) remains a major healthcare problem on a global scale. The tumor microenvironment (TME) plays an important and controversial role in cancer development, and the mechanism of the tumor's escape from immunological surveillance is still not clearly defined. We aim to investigate the expression of CD68 and CD47 in patients with different histological variants of CC, tumor characteristics, and burden. This is a retrospective cohort study performed on paraffin-embedded tumor tissues from 191 patients diagnosed with CC between 2014 and 2021 at the Medical University Pleven, Bulgaria. Slides for immunohistochemical (IHC) evaluation were obtained, and the expression of CD68 was scored in intratumoral (IT) and stromal (ST) macrophages (CD68+cells) using a three-point scoring scale. The CD47 expression was reported as an H-score. All statistical analyses were performed using R v. 4.3.1 for Windows. Infiltration by CD68-IT cells in the tumor depended on histological type and the expression of CD47. Higher levels of the CD47 H-score were significantly more frequent among patients in the early stage. Higher levels of infiltration by CD68-ST cells were associated with worse prognosis, and the infiltration of CD68-IT cells was associated with reduced risk of death from neoplastic disease. TME is a complex ecosystem that has a major role in the growth and development of tumors. Macrophages are a major component of innate immunity and, when associated with a tumor process, are defined as TAM. Tumor cells try to escape immunological surveillance in three ways, and one of them is reducing immunogenicity by the overexpression of negative coreceptors by T-lymphocytes and their ligands on the surface of tumor cells. One such mechanism is the expression of CD47 in tumor cells, which sends a "don't eat me" signal to the macrophages and, thus, prevents phagocytosis. To our knowledge, this is the first study that has tried to establish the relationship between the CD47 and CD68 expression levels and some clinicopathologic features in CC. We found that the only clinicopathological feature implicating the level of CD68 infiltration was the histological variant of the tumor, and only for CD68-IT-high levels were these observed in SCC. High levels of CD47 expression were seen more frequently in pT1B than pT2A and pT2B in the FIGO I stage than in the FIGO II and III stages. Infiltration by large numbers of CD68-IT cells was much more common among patients with a high expression of CD47 in tumor cells. A high level of infiltration by CD68-ST cells was associated with a worse prognosis, and a high level of infiltration by CD68-ST cells was associated with a lower risk of death from cancer.

Discovery of an embryonically derived bipotent population of endothelial-macrophage progenitor cells in postnatal aorta

Converging evidence indicates that extra-embryonic yolk sac is the source of both macrophages and endothelial cells in adult mouse tissues. Prevailing views are that these embryonically derived cells are maintained after birth by proliferative self-renewal in their differentiated states. Here we identify clonogenic endothelial-macrophage (EndoMac) progenitor cells in the adventitia of embryonic and postnatal mouse aorta, that are independent of Flt3-mediated bone marrow hematopoiesis and derive from an early embryonic CX3CR1+ and CSF1R+ source. These bipotent progenitors are proliferative and vasculogenic, contributing to adventitial neovascularization and formation of perfused blood vessels after transfer into ischemic tissue. We establish a regulatory role for angiotensin II, which enhances their clonogenic and differentiation properties and rapidly stimulates their proliferative expansion in vivo. Our findings demonstrate that embryonically derived EndoMac progenitors participate in local vasculogenic responses in the aortic wall by contributing to the expansion of endothelial cells and macrophages postnatally.

JDF promotes the apoptosis of M2 macrophages and reduces epithelial-mesenchymal transition and migration of liver cancer cells by inhibiting CSF-1/PI3K/AKT signaling pathway

Background

The interaction between cancer cells and the tumor microenvironment is of critical importance in liver cancer. Jiedu Granule formula (JDF) has been shown to minimize the risk of recurrence and metastasis following liver cancer resection. Investigating the mechanism underlying the therapeutic effects of JDF can extend its field of application and develop novel treatment approaches.

Methods

We established a rat liver orthotopic transplantation tumor model, and recorded the prognostic effects of JDF adjuvant therapy on the recurrence and metastasis of liver cancer. Liver and lung tissues were collected for immunofluorescence staining and H&E staining, respectively. In addition, THP-1 cells were incubated with PMA and IL-4 to induce them to differentiate into M2 macrophages. CSF-1 expression was knocked down using lentivirus to determine the function of CSF-1. Liver cancer cells were cultured with a conditioned medium (CM) or co-cultured with macrophages. Cell viability was determined using the MTT assay. The levels of CSF-1, CSF-1R, E-cadherin, N-cadherin, PI3K, AKT, and cleaved caspase-3 were detected using ELISA, Western blotting and qPCR. The ability of cells to migrate was assessed using cell scratch and transwell assays. Apoptosis was evaluated using flow cytometry.

Results

The JDF treatment decreased the risk of liver cancer metastasis after surgery and the infiltration of CD206/CD68 cells in liver cancer tissue. In cell experiments, JDF showed effects in suppressing M2 macrophages activity and downregulating the expression of CSF-1 and CSF-1R. The concentration of CSF-1 in the supernatant was also lower in the JDF-treated group. Futhermore, M2-CM was found to promote cancer cell migration and epithelial-mesenchymal transition (EMT); however, these effects were weakened after administering JDF. Knocking down endogenous CSF-1 in M2 macrophages resulted in a comparable suppression of cancer cell migration and EMT. Additionally, JDF treatment inhibited activation of the PI3K/AKT pathway, thus promoting the apoptosis of M2 macrophages.

Conclusions

Treatment with JDF reduced the EMT and migratory capacity of liver cancer cells, which might be attributed to the inhibition of M2 macrophage infiltration and interruption of the CSF-1/PI3K/AKT signaling pathway. This mechanism may hold significant implications for mitigating the risk of metastatic spread in the aftermath of hepatic surgery.

Research progress on the role of PTEN deletion or mutation in the immune microenvironment of glioblastoma

Recent advances in immunotherapy represent a breakthrough in solid tumor treatment but the existing data indicate that immunotherapy is not effective in improving the survival time of patients with glioblastoma. The tumor microenvironment (TME) exerts a series of inhibitory effects on immune effector cells, which limits the clinical application of immunotherapy. Growing evidence shows that phosphate and tension homology deleted on chromosome ten (PTEN) plays an essential role in TME immunosuppression of glioblastoma. Emerging evidence also indicates that targeting PTEN can improve the anti-tumor immunity in TME and enhance the immunotherapy effect, highlighting the potential of PTEN as a promising therapeutic target. This review summarizes the function and specific upstream and downstream targets of PTEN-associated immune cells in glioblastoma TME, providing potential drug targets and therapeutic options for glioblastoma.

Hypoxia-Driven Changes in Tumor Microenvironment: Insights into Exosome-Mediated Cell Interactions

Hypoxia, as a prominent feature of the tumor microenvironment, has a profound impact on the multicomponent changes within this environment. Under hypoxic conditions, the malignant phenotype of tumor cells, the variety of cell types within the tumor microenvironment, as well as intercellular communication and material exchange, undergo complex alterations. These changes provide significant prospects for exploring the mechanisms of tumor development under different microenvironmental conditions and for devising therapeutic strategies. Exosomes secreted by tumor cells and stromal cells are integral components of the tumor microenvironment, serving as crucial mediators of intercellular communication and material exchange, and have consequently garnered increasing attention from researchers. This review focuses on the mechanisms by which hypoxic conditions promote the release of exosomes by tumor cells and alter their encapsulated contents. It also examines the effects of exosomes derived from tumor cells, immune cells, and other cell types under hypoxic conditions on the tumor microenvironment. Additionally, we summarize current research progress on the potential clinical applications of exosomes under hypoxic conditions and propose future research directions in this field.

Surface Markers and Chemokines/Cytokines of Tumor-Associated Macrophages in Osteosarcoma and Other Carcinoma Microenviornments-Contradictions and Comparisons

Osteosarcoma (OS) is the most common primary bone tumor in children and adolescents. Prognosis is improving with advances in multidisciplinary treatment strategies, but the development of new anticancer agents has not, and improvement in prognosis for patients with pulmonary metastases has stalled. In recent years, the tumor microenvironment (TME) has gained attention as a therapeutic target for cancer. The immune component of OS TME consists mainly of tumor-associated macrophages (TAMs). They exhibit remarkable plasticity, and their phenotype is influenced by the TME. In general, surface markers such as CD68 and CD80 show anti-tumor effects, while CD163 and CD204 show tumor-promoting effects. Surface markers have potential value as diagnostic and prognostic biomarkers. The cytokines and chemokines produced by TAMs promote tumor growth and metastasis. However, the role of TAMs in OS remains unclear to date. In this review, we describe the role of TAMs in OS by focusing on TAM surface markers and the TAM-produced cytokines and chemokines in the TME, and by comparing their behaviors in other carcinomas. We found contrary results from different studies. These findings highlight the urgency for further research in this field to improve the stalled OS prognosis percentages.

NAD+ Metabolism Reprogramming Mediates Irradiation-Induced Immunosuppressive Polarization of Macrophages

PURPOSE

Radiation therapy stands as an important complementary treatment for head and neck squamous cell carcinoma (HNSCC), yet it does not invariably result in complete tumor regression. The infiltration of immunosuppressive macrophages is believed to mediate the radiation therapy resistance, whose mechanism remains largely unexplored. This study aimed to elucidate the role of immunosuppressive macrophages during radiation therapy and the associated underlying mechanisms.

METHODS AND MATERIALS

Male C3H mice bearing syngeneic SCC-VII tumor received irradiation (2 × 8 Gy). The impact of irradiation on tumor-infiltrating macrophages was assessed. Bone marrow-derived macrophages were evaluated in differentiation, proliferation, migration, and inflammatory cytokines after treatment of irradiated tumor culture medium and irradiated tumor-derived extracellular vesicles (irTEVs). A comprehensive metabolomics profiling of the irTEVs was conducted using liquid chromatography-mass spectrometry, whereas key metabolites were investigated for their role in the mechanism of immunosuppression of macrophages in vitro and in vivo.

RESULTS

Radiation therapy on SCC-VII syngeneic graft tumors increased polarization of both M1 and M2 macrophages in the tumor microenvironment and drove infiltrated macrophages toward an immunosuppressive phenotype. Irradiation-induced polarization and immunosuppression of macrophages were dependent on irTEVs which delivered an increased amount of niacinamide (NAM) to macrophages. NAM directly bound to the nuclear factor kappa-B transcriptional activity regulator USP7, through which NAM reduced translocation of nuclear factor kappa-B into the nucleus, thereby decreasing the release of cytokines interleukin 6 and interleukin 8. Increased enzyme activity of NAM phosphoribosyl transferase which is the rate-limiting enzyme of NAD+ metabolism, contributed to the irradiation-induced accumulation levels of NAM in irradiated HNSCC and irTEVs. Inhibition of NAM phosphoribosyl transferase decreased NAM levels in irTEVs and increased radiation therapy sensitivity by alleviating the immunosuppressive function of macrophages.

CONCLUSIONS

Radiation therapy could induce NAD+ metabolic reprogramming of HNSCC cells, which regulate macrophages toward an immunosuppressive phenotype. Pharmacologic targeting of NAD+ metabolism might be a promising strategy for radiation therapy sensitization of HNSCC.

Hypoxia-inducible factor-1α promotes macrophage functional activities in protecting hypoxia-tolerant large yellow croaker (Larimichthys crocea) against Aeromonas hydrophila infection

The immune system requires a high energy expenditure to resist pathogen invasion. Macrophages undergo metabolic reprogramming to meet these energy requirements and immunologic activity and polarize to M1-type macrophages. Understanding the metabolic pathway switching in large yellow croaker (Larimichthys crocea) macrophages in response to lipopolysaccharide (LPS) stimulation and whether this switching affects immunity is helpful in explaining the stronger immunity of hypoxia-tolerant L. crocea. In this study, transcript levels of glycolytic pathway genes (Glut1 and Pdk1), mRNA levels or enzyme activities of glycolytic enzymes [hexokinase (HK), phosphofructokinase (PFK), pyruvate kinase (PK), and lactate dehydrogenase A (LDHA)], aerobic respiratory enzymes [pyruvate dehydrogenase (PDH), isocitrate dehydrogenase (IDH), and succinate dehydrogenase (SDH)], metabolites [lactic acid (LA) and adenosine triphosphate (ATP)], levels of bactericidal products [reactive oxygen species (ROS) and nitric oxide (NO)], and transcripts and level changes of inflammatory factors [IL1β, TNFα, and interferon (IFN) γ] were detected in LPS-stimulated L. crocea head kidney macrophages. We showed that glycolysis was significantly induced, the tricarboxylic acid (TCA) cycle was inhibited, and metabolic reprogramming occurred, showing the Warburg effect when immune cells were activated. To determine the potential regulatory mechanism behind these changes, LcHIF-1α was detected and found to be significantly induced and transferred to the nucleus after LPS stimulation. LcHif-1α interference led to a significant reduction in glycolytic pathway gene transcript expression, enzyme activity, metabolites, bactericidal substances, and inflammatory factor levels; a significant increase in the aerobic respiration enzymes; and decreased migration, invasion, and phagocytosis. Further ultrastructural observation by electron microscopy showed that fewer microspheres contained phagocytes and that more cells were damaged after LcHif-1α interference. LcHif-1α overexpression L. crocea head kidney macrophages showed the opposite trend, and promoter activities of Ldha and Il1β were significantly enhanced after LcHif-1α overexpression in HEK293T cells. Our data showed that LcHIF-1α acted as a metabolic switch in L. crocea macrophages and was important in polarization. Hypoxia-tolerant L. crocea head kidney showed a stronger Warburg effect and inhibited the TCA cycle, higher metabolites, and bactericidal substance levels. These results collectively revealed that LcHif-1α may promote the functional activities of head kidney macrophages in protecting hypoxia-tolerant L. crocea from Aeromonas hydrophila infection.

Higher inflammatory response in hepatocellular carcinoma is associated with immune cell infiltration and a better outcome

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) often develops from chronic liver inflammation. Inflammation within a tumor can either promote cancer progression or activate an immune response against it. This study aims to determine the clinical significance of enhanced inflammation in HCC.

METHODS

Data from 655 HCC patients across four cohorts (TCGA, GSE6764, GSE76427, GSE89377) were examined. Inflammatory response was quantified using a scoring system derived from the gene set variation analysis of the "INFLAMMATORY_RESPONSE" gene set.

RESULTS

A stepwise increase in inflammatory response was noted from normal liver to cirrhosis, with consistently lower levels in HCC across both GSE6764 and GSE89377 cohorts (both p < 0.001). Similar trends were observed in interferon response, pathways such as IL6/JAK/STAT3 and complement signaling, coagulation cascade, and allograft rejection (all p < 0.02). HCCs with high inflammatory response were associated with increased immune cell infiltrations (p < 0.01) and cytolytic activity (p < 0.001). Interestingly, these HCCs had reduced mutation rates, no relationship with cell proliferation, and displayed both immune responses and pro-cancerous signals including epithelial-mesenchymal transition, KRAS, and hypoxia. Further, a high inflammatory score correlated with improved disease-free survival in TCGA (p = 0.034) and overall survival in GSE76427 (p = 0.008).

CONCLUSION

HCC with higher levels of inflammatory response demonstrated increased immune cell infiltration, enhanced immune-related and other pro-cancerous-related signaling, and showed a trend toward a better patient prognosis.

Multicellular tumor spheroid model to study the multifaceted role of tumor-associated macrophages in PDAC

While considerable efforts have been made to develop new therapies, progress in the treatment of pancreatic cancer has so far fallen short of patients' expectations. This is due in part to the lack of predictive in vitro models capable of accounting for the heterogeneity of this tumor and its low immunogenicity. To address this point, we have established and characterized a 3D spheroid model of pancreatic cancer composed of tumor cells, cancer-associated fibroblasts, and blood-derived monocytes. The fate of the latter has been followed from their recruitment into the tumor spheroid to their polarization into a tumor-associated macrophage (TAM)-like population, providing evidence for the formation of an immunosuppressive microenvironment.This 3D model well reproduced the multiple roles of TAMs and their influence on drug sensitivity and cell migration. Furthermore, we observed that lipid-based nanosystems consisting of sphingomyelin and vitamin E could affect the phenotype of macrophages, causing a reduction of characteristic markers of TAMs. Overall, this optimized triple coculture model gives a valuable tool that could find useful application for a more comprehensive understanding of TAM plasticity as well as for more predictive drug screening. This could increase the relevance of preclinical studies and help identify effective treatments.

Multifactorial risk prediction analysis of liver metastasis in colorectal cancer: incorporating programmed cell death ligand 1 combined positive score and other factors

BACKGROUND

The occurrence of liver metastasis significantly affects the prognosis of colorectal cancer (CRC). Existing research indicates that primary tumor location, vascular invasion, lymph node metastasis, and abnormal preoperative tumor markers are risk factors for CRC liver metastasis. Positive expression of programmed cell death ligand 1 (PD-L1) may serve as a favorable prognostic marker for nasopharyngeal and gastric cancers, in which combined positive score (CPS) quantifies the level of PD-L1 expression. This study aimed to explore CPS as a potential risk factor for CRC liver metastasis and integrate other independent risk factors to establish a novel predictive model for CRC liver metastasis.

METHODS

A retrospective analysis was conducted on 437 patients with CRC pathologically diagnosed at The Second Xiangya Hospital of Central South University from January 1, 2019, to December 31, 2021. Data were collected, including CPS, age, gender (male and female), primary tumor location, Ki-67 expression, pathologic differentiation, neural invasion, vascular invasion, lymph node metastasis, and preoperative tumor markers. The optimal cutoff point for the continuous variable CPS was determined using the Youden index, and all CPSs were dichotomized into high- and low-risk groups based on this threshold (scores below the threshold were considered high risk, and score above the threshold were considered low risk). Univariate logistic regression analysis was employed to identify risk factors for CRC liver metastasis, followed by multivariate logistic regression analysis to integrate the selected risk factors. The predictive model was validated through the construction of receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). A nomogram was constructed for visualization.

RESULTS

The determined cutoff point for PD-L1 CPS was 4.5, with scores below this threshold indicating a high risk of CRC liver metastasis. In addition, primary tumor origin other than the rectum, presence of pericolonic lymph node metastasis, and abnormal levels of tumor markers carcinoembryonic antigen and cancer antigen 19-9 were identified as independent risk factors for CRC liver metastasis. The constructed clinical prediction model demonstrated good predictive ability and accuracy, with an area under the ROC curve of 0.871 (95% CI, 0.838-0.904).

CONCLUSION

The exploration and validation of CPS as a novel predictor of CRC liver metastasis were performed. Based on these findings, a new clinical prediction model for CRC liver metastasis was developed by integrating other independent risk factors. The DCA, clinical impact curve, and nomogram graph constructed on the basis of this model have significant clinical implications and guide clinical practice.

Enhanced angiogenesis of human umbilical vein endothelial cells via THP-1-derived M2c-like macrophages and treatment with proteasome inhibitors 'bortezomib and ixazomib'

The leading cause of cancer-related death is lung cancer, with metastasis being the most common cause of death. To elucidate the role of macrophages in lung cancer and angiogenesis processes, we established an in vitro co-culture model of A549 or HUVEC with THP-1 cells that polarized to M2c macrophages with hydrocortisone. The proteasome inhibitors bortezomib and ixazomib were investigated for their effects on proliferation, invasion, migration, metastasis, and angiogenesis pathways. The effects of bortezomib and ixazomib on gene expression in gene panels, including crucial genes related to angiogenesis and proteasomes, were investigated after the co-culture model to determine these effects at the molecular level. In conclusion, bortezomib and ixazomib showed antiproliferative effects in both cells, as well as in M2c macrophage co-culture. M2c macrophages also increased invasion in A549 cells and both invasion and migration in HUVEC. mRNA expression upregulation, specifically in the NFKB and VEGF genes, supported the metastatic and angiogenic effects found in A549 and HUVEC with M2c macrophage co-culture. Additionally, bortezomib inhibited the VEGFB pathway in HUVEC and NFKB1 in A549 cells. The significant findings obtained as a result of this study will provide information regarding angiogenesis induced by M2 macrophages.

Antitumor activity of dictamnine against colorectal cancer through induction of ferroptosis and inhibition of M2 macrophage polarization via the MAPK signaling

Colorectal cancer (CRC) is an aggressive cancer type globally. Surgery and chemotherapy are often ineffective at curing CRC. Dictamnine is a natural product derived from Dictamnus dasycarpus Turcz. root bark and possesses multi-pharmacological properties, including anticancer effects. Nevertheless, the biological roles and the possible mechanism of dictamnine in CRC are still unclear. Here, we demonstrated that dictamnine blocked cell viability and proliferation in DLD-1 human colorectal adenocarcinoma cells and LoVo human colon cancer cells. Dictamnine triggered CRC cell ferroptosis, as evidenced by enhanced levels of reactive oxygen species, malondialdehyde, and Fe2+ levels, alongside downregulation of glutathione peroxidase 4 protein expression. In addition, CD163 (HPA ID: HPA046404) was highly expressed and CD68 (HPA ID: CAB000051) was lowly expressed in CRC tissues and CRC cell culture medium-cultured THP-1 monocytes-derived macrophages. The patients with CD163 low-expression lived much longer than those with CD163 high-expression, indicating that M2 polarization of macrophages was related to poor prognosis of CRC. Dictamnine markedly inhibited CD163 protein expression, transforming growth factor-β and arginase 1 mRNA expressions and IL-10 production in macrophages with CRC cell co-culture, suggesting that dictamnine impeded M2 polarization of macrophages. Mechanistically, dictamnine repressed ERK phosphorylation in CRC cells. The treatment with the ERK activator tBHQ counteracted the effects of dictamnine on CRC cell proliferation and ferroptosis, as well as its inhibitory effect on M2 polarization of macrophages. Results of a xenograft model showed that dictamnine effectively hindered CRC tumor growth in vivo. Collectively, these data provide evidence for the clinical trials of dictamnine as a novel drug for CRC therapy.

An herbal formula Shenlian decoction upregulates M1/M2 macrophage proportion in hepatocellular carcinoma by suppressing complement cascade

The immunosuppressive microenvironment is a vital factor for the hepatocellular carcinoma (HCC) progression. However, effective treatment is lacking at current. Shenlian decoction (SLD) is a registered herbal therapy for the HCC treatment, but the underlying mechanism of SLD remains largely elusive. Here, we aimed to explore the anti-tumor effect of SLD in the treatment of HCC. SLD was intragastrically given after the tumor initiation in β-catenin/C-Met or DEN and CCl4 induced HCC mouse model. The tumor growth levels were evaluated by liver weight and histological staining. The tumor-infiltrating immune cells were detected by immunological staining and flow cytometry. The mechanism of the SLD was detected by non-targeted proteomics and verified by a cell co-culture system. The result showed that SLD significantly attenuated HCC progression. SLD promoted macrophage infiltration and increased the M1/M2 macrophage ratio within the tumor tissues. Non-targeted proteomics showed the inhibition of complement C5/C5a signaling is the key mechanism of SLD. Immunological staining showed SLD inhibited C5/C5a expression and C5aR1+ macrophage infiltration. The suggested mechanism was demonstrated by application of C5aR1 inhibitor, PMX-53 in mouse HCC model. Hepatoma cell-macrophage co-culture showed SLD targeted hepatoma cells and inhibited the supernatant-induced macrophage M2 polarization. SLD inhibited AMPK/p38 signaling which is an upstream mechanism of C5 transcription. In conclusion, we found SLD relieved immune-suppressive environment by inhibiting C5 expression. SLD could suppress the C5 secretion in hepatoma cells via inhibition of AMPK/p38 signaling. We suggested that SLD is a potential herbal therapy for the treatment of HCC by alleviating immune-suppressive status.

Synthetic Biomimetic Liposomes Harness Efferocytosis Machinery for Highly Efficient Macrophages-Targeted Drug Delivery to Alleviate Inflammation

Macrophages play pivotal roles in the regulation of inflammatory responses and tissue repair, making them a prime target for inflammation alleviation. However, the accurate and efficient macrophages targeting is still a challenging task. Motivated by the efficient and specific removal of apoptotic cells by macrophages efferocytosis, a novel biomimetic liposomal system called Effero-RLP (Efferocytosis-mediated Red blood cell hybrid Liposomes) is developed which incorporates the membrane of apoptotic red blood cells (RBCs) with liposomes for the purpose of highly efficient macrophages targeting. Rosiglitazone (ROSI), a PPARγ agonist known to attenuate macrophage inflammatory responses, is encapsulated into Effero-RLP as model drug to regulate macrophage functions in DSS-induced colitis mouse model. Intriguingly, the Effero-RLP exhibits selective and efficient uptake by macrophages, which is significantly inhibited by the efferocytosis blocker Annexin V. In animal models, the Effero-RLP demonstrates rapid recognition by macrophages, leading to enhanced accumulation at inflammatory sites. Furthermore, ROSI-loaded Effero-RLP effectively alleviates inflammation and protects colon tissue from injury in the colitis mouse model, which is abolished by deletion of macrophages from mice model. In conclusion, the study highlights the potential of macrophage targeting using efferocytosis biomimetic liposomes. The development of Effero-RLP presents novel and promising strategies for alleviating inflammation.

Research advances on signaling pathways regulating the polarization of tumor-associated macrophages in lung cancer microenvironment

Lung cancer (LC) is one of the most common cancer worldwide. Tumor-associated macrophages (TAMs) are important component of the tumor microenvironment (TME) and are closely related to the stages of tumor occurrence, development, and metastasis. Macrophages are plastic and can differentiate into different phenotypes and functions under the influence of different signaling pathways in TME. The classically activated (M1-like) and alternatively activated (M2-like) represent the two polarization states of macrophages. M1 macrophages exhibit anti-tumor functions, while M2 macrophages are considered to support tumor cell survival and metastasis. Macrophage polarization involves complex signaling pathways, and blocking or regulating these signaling pathways to enhance macrophages' anti-tumor effects has become a research hotspot in recent years. At the same time, there have been new discoveries regarding the modulation of TAMs towards an anti-tumor phenotype by synthetic and natural drug components. Nanotechnology can better achieve combination therapy and targeted delivery of drugs, maximizing the efficacy of the drugs while minimizing side effects. Up to now, nanomedicines targeting the delivery of various active substances for reprogramming TAMs have made significant progress. In this review, we primarily provided a comprehensive overview of the signaling crosstalk between TAMs and various cells in the LC microenvironment. Additionally, the latest advancements in novel drugs and nano-based drug delivery systems (NDDSs) that target macrophages were also reviewed. Finally, we discussed the prospects of macrophages as therapeutic targets and the barriers to clinical translation.

Eleven inflammation-related genes risk signature model predicts prognosis of patients with breast cancer

Background

Changes in gene expression are associated with malignancy. Analysis of gene expression data could be used to reveal cancer subtypes, key molecular drivers, and prognostic characteristics and to predict cancer susceptibility, treatment response, and mortality. It has been reported that inflammation plays an important role in the occurrence and development of tumors. Our aim was to establish a risk signature model of breast cancer with inflammation-related genes (IRGs) to evaluate their survival prognosis.

Methods

We downloaded 200 IRGs from the Molecular Signatures Database (MSigDB). The data of breast cancer were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Differential gene expression analysis, the least absolute shrinkage and selection operator (LASSO), Cox regression analysis, and overall survival (OS) analysis were used to construct a multiple-IRG risk signature. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were carried out to annotate functions of the differentially expressed IRGs (DEIRGs) The predictive accuracy of the prognostic model was evaluated by time-dependent receiver operating characteristic (ROC) curves. Subsequently, nomograms were constructed to guide clinical application according to the univariate and multivariate Cox proportional hazards regression analyses. Eventually, we applied gene set variation analysis (GSVA), mutation analysis, immune infiltration analysis, and drug response analysis to compare the differences between high- and low-risk patients.

Results

Totally, 65 DEIRGs were obtained after comparing 1,092 breast cancer tissues with 113 paracancerous tissues in TCGA. Among them, 11 IRGs (IL18, IL12B, RASGRP1, HPN, CLEC5A, SCARF1, TACR3, VIP, CCL2, CALCRL, ABCA1) were screened with nonzero coefficient by LASSO regression analysis to construct the prognostic model, which was validated in GSE96058.The 11-gene IRGs risk signature model stratified patients into high- or low-risk groups, with those in the low-risk group having longer survival time and less deaths. Multivariate Cox analysis manifested that risk score, age, and stage were the three independent prognostic factors for breast cancer patients. There were 12 pathways with higher activities and 24 pathways with lower activities in the high-risk group compared with the low-risk group, yet no difference of gene mutation load was observed between the two groups. In immune infiltration analysis, we noted that the proportion of T cells showed a decreased trend according to the increase of risk score and most of the immune cells were enriched in the low-risk group. Inversely, macrophages M2 were more highly distributed in the high-risk group. We identified 67 approved drugs that showed a different effect between the high- and low-risk patients and the top 2 gene-drug pairs were IL12B-sunitinib and SCARF1-ruxolitinib.

Conclusions

The 11-IRG risk signature model is a promising tool to predict the survival of breast cancer patients and the expressions of IL12B and SCARF1 may serve as potential targets for therapy of breast cancer.

NIR-II Light-Actuated Nanomotors for Enhanced Photoimmunotherapy Toward Hepatocellular Carcinoma

Light-propelled nanomotors, which can convert external light into mechanical motion, have shown considerable potential in the construction of a new generation of drug delivery systems. However, the therapeutic efficacy of light-driven nanomotors is always unsatisfactory due to the limited penetration depth of near-infrared-I (NIR-I) light and the inherent biocompatibility of the motor itself. Herein, an asymmetric nanomotor (Pd@ZIF-8/R848@M JNMs) with efficient motion capability is successfully constructed for enhanced photoimmunotherapy toward hepatocellular carcinoma. Under near-infrared-II (NIR-II) irradiation, Pd@ZIF-8/R848@M JNMs convert light energy into heat energy, exhibiting self-thermophoretic locomotion to penetrate deeper into tumor tissues to achieve photothermal therapy. At the same time, functionalized with an immune-activated agent Resiquimod (R848), our nanomotors could convert a "cold tumor" into a "hot tumor", transforming the immunosuppressive microenvironment into an immune-activated state, thus achieving immunotherapy. Dual photoimmunotherapy of the as-developed NIR-II light-driven Pd@ZIF-8/R848@M JNMs demonstrates considerable tumor inhibition effects, offering a promising therapeutic approach in the field of anticancer therapy.

VISTA deficiency exerts anti-tumor effects in breast cancer through regulating macrophage polarization

Growing evidence had showed that tumor-associated macrophages (TAMs) have a tumor-promoting M2 phenotype which could drive pathological phenomena. In breast cancer, TAMs are abundantly present and may play an important role in the development of breast cancer. V-domain immunoglobulin suppressor of T cell activation (VISTA) is a novel inhibitory checkpoint and immunotherapy target for tumor through regulating immune response. However, its effects on macrophages have not been investigated, which was also the focus of this study. Here, the scRNA-seq data further revealed that VISTA was highly expressed in multiple macrophage subclusters. In vitro experiments showed that the absence of VISTA enhanced the M1 polarization of macrophages, inhibited the M2 polarization of macrophages and the proliferation and phagocytosis of 4 T1 cells induced by M2-CM. VISTA regulated the activation of STAT1 and STAT6 signaling pathways in the process of macrophage polarization. In vivo experiments demonstrated that VISTA deficient mice exhibited reduced tumor growth, possibly due to the increase of M1 macrophages and the decrease of M2 macrophages. In summary, our study is the first to reveal the effect of VISTA on macrophages in breast cancer, which showed that VISTA affects tumor growth by critically regulating the macrophage polarization through the STAT pathway.

Lenvatinib targets STAT-1 to enhance the M1 polarization of TAMs during hepatocellular carcinoma progression

Lenvatinib, a multitarget kinase inhibitor, has been proven to be effective in the treatment of advanced hepatocellular carcinoma. It has been previously demonstrated that tumour associated macrophages (TAMs) in tumour tissues can promote HCC growth, invasion and metastasis. Furthermore, lenvatinib has certain immunomodulatory effects on the treatment of HCC. However, the role of lenvatinib in macrophage polarization during HCC treatment has not been fully explored. In this study, we used a variety of experimental methods both in vitro and in vivo to investigate the effect of lenvatinib on TAMs during HCC progression. This study is the first to show that lenvatinib can alter macrophage polarization in both humans and mice. Moreover, macrophages treated with lenvatinib in vitro displayed enhanced classically activated macrophages (M1) activity and suppressed liver cancer cell proliferation, invasion, and migration. Furthermore, during the progression of M1 macrophage polarization induced by lenvatinib, STAT-1 was the main target transcription factor, and inhibiting STAT-1 activity reversed the effect of lenvatinib. Overall, the present study provides a theoretical basis for the immunomodulatory function of lenvatinib in the treatment of HCC.

PPAR-γ/NF-kB/AQP3 axis in M2 macrophage orchestrates lung adenocarcinoma progression by upregulating IL-6

Aquaporin 3 (AQP3), which is mostly expressed in pulmonary epithelial cells, was linked to lung adenocarcinoma (LUAD). However, the underlying functions and mechanisms of AQP3 in the tumor microenvironment (TME) of LUAD have not been elucidated. Single-cell RNA sequencing (scRNA-seq) was used to study the composition, lineage, and functional states of TME-infiltrating immune cells and discover AQP3-expressing subpopulations in five LUAD patients. Then the identifications of its function on TME were examined in vitro and in vivo. AQP3 was associated with TNM stages and lymph node metastasis of LUAD patients. We classified inter- and intra-tumor diversity of LUAD into twelve subpopulations using scRNA-seq analyses. The analysis showed AQP3 was mainly enriched in subpopulations of M2 macrophages. Importantly, mechanistic investigations indicated that AQP3 promoted M2 macrophage polarization by the PPAR-γ/NF-κB axis, which affected tumor growth and migration via modulating IL-6 production. Mixed subcutaneous transplanted tumor mice and Aqp3 knockout mice models were further utilized, and revealed that AQP3 played a critical role in mediating M2 macrophage polarization, modulating glucose metabolism in tumors, and regulating both upstream and downstream pathways. Overall, our study demonstrated that AQP3 could regulate the proliferation, migration, and glycometabolism of tumor cells by modulating M2 macrophages polarization through the PPAR-γ/NF-κB axis and IL-6/IL-6R signaling pathway, providing new insight into the early detection and potential therapeutic target of LUAD.

Hallmarks of perineural invasion in pancreatic ductal adenocarcinoma: new biological dimensions

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignant tumor with a high metastatic potential. Perineural invasion (PNI) occurs in the early stages of PDAC with a high incidence rate and is directly associated with a poor prognosis. It involves close interaction among PDAC cells, nerves and the tumor microenvironment. In this review, we detailed discuss PNI-related pain, six specific steps of PNI, and treatment of PDAC with PNI and emphasize the importance of novel technologies for further investigation.

Correlation between Tregs and ICOS-induced M2 macrophages polarization in colorectal cancer progression

Objective

To explore the mechanism by which Tregs promote the progression of colorectal cancer by inducing tumor-associated macrophages to polarize into M2 type via ICOS.

Methods

Postoperative pathological tissues and clinical pathological data of 268 colorectal cancer patients who underwent initial surgery were collected. Immunohistochemistry (IHC) was used to detect the expression levels of ICOS, CD163 (a marker for M2 macrophages), and Foxp3 (a marker for Tregs) in cancerous, adjacent non-tumorous, and normal tissues. The relationship of ICOS, M2 macrophages, and Tregs in CRC with clinical pathological characteristics and pre-surgical tumor markers (such as CEA and CA199) was explored.

Results

The expression levels of M2 macrophages and Tregs increased with tumor progression, while ICOS expression showed a decreasing trend. Compared to adjacent and normal tissues, the expression levels of ICOS, M2 macrophages, and Tregs were higher in CRC tissues. The expression levels of M2 macrophages and Tregs were significantly positively correlated with tumor markers, while ICOS expression was significantly negatively correlated.

Conclusion

Tumor-associated m2 macrophages induced by Tregs and ICOS participate in the dynamic balance of the colorectal cancer tumor microenvironment, and their interaction affects colorectal carcinogenesis and progression. High levels of ICOS are associated with better long-term survival rates.

[Advances of Fundamental Research on Traditional Chinese Medicine in Regulation of Tumor-associated Macrophages for the Prevention and Treatment of Lung Cancer Metastasis]

Lung cancer is the leading cause of cancer-related deaths worldwide, with metastasis being the primary cause of mortality in lung cancer patients, and its prevention and control efficacy remain limited. In recent years, immunotherapy has emerged as a promising direction for overcoming the bottleneck of metastasis. Macrophages, as essential components of innate immunity, participate in the entire process of tumor initiation and progression. Tumor-associated macrophages (TAMs) represent the most abundant immune population in the tumor microenvironment (TME), displaying both anti-tumor M1-like and pro-tumor M2-like phenotypes. The latter promotes tumor invasion and metastasis, angiogenesis, lymphangiogenesis, immune suppression, and reactivation of dormant disseminated tumor cells (DTCs), thereby facilitating tumor metastasis. In recent years, traditional Chinese medicine (TCM) has shown significant efficacy in inhibiting tumor metastasis and has been extensively validated. It exerts anti-tumor effects by reducing the recruitment of TAMs, inhibiting M2-like polarization, and modulating cytokines and proteins in the TME. This paper reviews the relationship between TAMs and lung cancer metastasis, elucidates the targets and mechanisms of TCM in regulating TAMs to prevent and treat lung cancer metastasis, aiming to provide insights into lung cancer prevention and treatment.
.

High-motility pro-tumorigenic monocytes drive macrophage enrichment in the tumor microenvironment

Enrichment of tumor-associated macrophages (TAMΦs) in the tumor microenvironment correlates with worse clinical outcomes in triple-negative breast cancer (TNBC) patients, prompting the development of therapies to inhibit TAMΦ infiltration. However, the lackluster efficacy of CCL2-based chemotaxis blockade in clinical trials suggests that a new understanding of monocyte/macrophage infiltration may be necessary. Here we demonstrate that random migration, and not only chemotaxis, drives macrophage tumor infiltration. We identified tumor- associated monocytes (TAMos) that display a dramatically enhanced migration capability, induced rapidly by the tumor microenvironment, that drives effective tumor infiltration, in contrast to low-motility differentiated macrophages. TAMo, not TAMΦ, promotes cancer cell proliferation through activation of the MAPK pathway. IL-6 secreted both by cancer cells and TAMo themselves enhances TAMo migration by increasing dendritic protrusion dynamics and myosin- based contractility via the JAK2/STAT3 signaling pathway. Independent from CCL2 mediated chemotaxis, IL-6 driven enhanced migration and pro-proliferative effect of TAMo were validated in a syngeneic TNBC mouse model. Depletion of IL-6 in cancer cells significantly attenuated monocyte infiltration and reversed TAMo-induced cancer cell proliferation. This work reveals the critical role random migration plays in monocyte driven TAMΦ enrichment in a tumor and pinpoints IL-6 as a potential therapeutic target in combination with CCL2 to ameliorate current strategies against TAMΦ infiltration.

A novel signature constructed by cuproptosis-related RNA methylation regulators suggesting downregulation of YTHDC2 may induce cuproptosis resistance in colorectal cancer

BACKGROUND

A newly identified type of cell death due to intracellular copper accumulation is known as cuproptosis and RNA methylation is a post-transcriptional modification mechanism, both of which perform vital roles in the immune microenvironment of colorectal cancer (CRC), but the link between the two needs more research.

METHODS

TCGA database provided RNA-seq data and details clinically of CRC samples. Cuproptosis-related RNA methylation regulators (CRRMRs) were identified by correlation analysis. We screened 6 CRRMRs for prognostic model construction by employing LASSO-Cox regression analysis and calculated risk scores by CRRMRs (CuMS). GSE39582 and GSE38832 cohort were used as external validation sets. This research concentrated on the connection between the prognostic model and somatic mutation, anti-cancer drug sensitivity, immune infiltration, immune checkpoint expression. In addition, we investigated the differential expression of YTHDC2 in epithelial cell subpopulations by single-cell analysis with GSE166555, calculated cuproptosis scores and performed pathway enrichment. In vitro experiments were performed to explore the consequences of knockdown of YTHDC2 on CRC cell proliferation and migration, as well as changes in CRC cell viability in response to elesclomol after knockdown of YTHDC2. In vivo experiments, we constructed the cell line-derived xenograft model to further validate the results of the in vitro experiments.

RESULTS

The prognosis of CRC can be predicted by CuMS, which GSE39582 and GSE38832 confirmed. Two CuMS groups showed different tumor mutation burden (TMB) and immune infiltration. CuMS was connected to emerging immune checkpoints CD47 and PVR, therefore, it can be clinically complementary to TMB and microsatellite instability (MSI) status. In single-cell analysis, a subpopulation of epithelial cells with high YTHDC2 expression had a high cuproptosis score. In vitro experiments, knocking down YTHDC2 promoted cell proliferation and migration in CRC, and weaken the inhibitory effect of elesclomol and elesclomol-Cu on cell viability, which in vivo experiments validated.

CONCLUSION

We developed a prognostic model constructed by 6 CRRMRs to assess overall survival and immune microenvironment of CRC patients. YTHDC2 might regulate cuproptosis in multiple ways.

Molecular and Pathobiology of Canine Mammary Tumour: Defining a Translational Model for Human Breast Cancer

Canine mammary tumours (CMT) have histological, clinicopathological and molecular resemblances to human breast cancer (HBC), positioning them as viable models for studying the human disease. CMT initiation and progression occur spontaneously in immune-competent animals, which challenge the suggested limitations of genetically modified mice, also enabling the evaluation of immunotherapies in canine patients. Dogs have shorter life expectancy compared to humans, and cancer advances more rapidly in this species. This makes it possible to perform studies about the clinical efficacy of new therapeutic modalities in a much shorter time than in human patients. The identification of biomarkers for tumour subtypes, progression and treatment response paves the way for the development of novel therapeutic and diagnostic approaches. This review addresses the similarities between CMT and HBC and the molecular signatures identified in CMT samples that have been explored to date. We proposed a detailed molecular exploration of the CMT stroma using state-of-the-art methods in transcriptomics and proteomics. Using CMT as an analog for HBC not only helps to understand the complexities of the disease, but also to advance comparative oncology to the next level to prove the claim of dogs as a valid translational model.

Glycolysis-related five-gene signature correlates with prognosis and immune infiltration in gastric cancer

BACKGROUND

Gastric cancer (GC) is one of the most common malignancies worldwide. Glycolysis has been demonstrated to be pivotal for the carcinogenesis of GC.

AIM

To develop a glycolysis-based gene signature for prognostic evaluation in GC patients.

METHODS

Differentially expressed genes correlated with glycolysis were identified in stomach adenocarcinoma data (STAD). A risk score was established through a univariate Cox and least absolute shrinkage and selection operator analysis. The model was evaluated using the area under the receiver operating characteristic curves. RNA-sequencing data from high- and low-glycolysis groups of STAD patients were analyzed using Cibersort algorithm and Spearman correlation to analyze the interaction of immune cell infiltration and glycolysis. Multiomics characteristics in different glycolysis status were also analyzed.

RESULTS

A five-gene signature comprising syndecan 2, versican, malic enzyme 1, pyruvate carboxylase and SRY-box transcription factor 9 was constructed. Patients were separated to high- or low-glycolysis groups according to risk scores. Overall survival of patients with high glycolysis was poorer. The sensitivity and specificity of the model in prediction of survival of GC patients were also observed by receiver operating characteristic curves. A nomogram including clinicopathological characteristics and the risk score also showed good prediction for 3- and 5-year overall survival. Gene set variation analysis showed that high-glycolysis patients were related to dysregulation of pancreas beta cells and estrogen late pathways, and low-glycolysis patients were related to Myc targets, oxidative phosphorylation, mechanistic target of rapamycin complex 1 signaling and G2M checkpoint pathways. Tumor-infiltrating immune cells and multiomics analysis suggested that the different glycolysis status was significantly correlated with multiple immune cell infiltration. The patients with high glycolysis had lower tumor mutational burden and neoantigen load, higher incidence of microsatellite instability and lower chemosensitivity. High glycolysis status was often found among patients with grade 2/3 cancer or poor prognosis.

CONCLUSION

The genetic characteristics revealed by glycolysis could predict the prognosis of GC. High glycolysis significantly affects GC phenotype, but the detailed mechanism needs to be further studied.

TRIM59 deficiency promotes M1 macrophage activation and inhibits colorectal cancer through the STAT1 signaling pathway

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.

Lactate activates CCL18 expression via H3K18 lactylation in macrophages to promote tumorigenesis of ovarian cancer

This study investigates the role of lactate in the genesis and progression of ovarian cancer (OV) and explores the underlying mechanisms. Serum lactate levels show a positive correlation with tumor grade and poor prognosis in patients with OV. Bioinformatics analysis identifies CCL18 as a lactate-related gene in OV. CCL18 is up-regulated in cancerous tissues and positively related to serum lactate levels in OV patients. THP-1 cells are exposed to phorbol-12-myristate-13-acetate for M0 macrophage induction. The results of RT-qPCR and ELISA for M1/M2 macrophage-related markers and inflammatory cytokines show that the exposure of lactate to macrophages induces M2 polarization. Based on the coculture of OV cells with macrophages, lactate-treated macrophages induces a significant increase in the proliferation and migration of OV cells. However, these effects can be reversed by silencing of Gpr132 in macrophages or treatment with anti-CCL18 antibody. Experiments using the xenograft model verify that the oncogenic role of lactate in tumor growth and metastasis relies on Gpr132 and CCL18. ChIP-qPCR and luciferase reporter assays reveal that lactate regulates CCL18 expression via H3K18 lactylation. In conclusion, lactate is a potential therapeutic target for OV. It is involved in tumorigenesis by activating CCL18 expression via H3K18 lactylation in macrophages.

MicroRNA-532 as a probable diagnostic and therapeutic marker in cancer patients

The high mortality rate in cancer patients is always one of the main challenges of the health systems globally. Several factors are involved in the high rate of cancer related mortality, including late diagnosis and drug resistance. Cancer is mainly diagnosed in the advanced stages of tumor progression that causes the failure of therapeutic strategies and increases the death rate in these patients. Therefore, assessment of the molecular mechanisms associated with the occurrence of cancer can be effective to introduce early tumor diagnostic markers. MicroRNAs (miRNAs) as the stable non-coding RNAs in the biological body fluids are involved in regulation of cell proliferation, migration, and apoptosis. MiR-532 deregulation has been reported in different tumor types. Therefore, in the present review we discussed the role of miR-532 during tumor growth. It has been shown that miR-532 has mainly a tumor suppressor role through the regulation of transcription factors, chemokines, and signaling pathways such as NF-kB, MAPK, PI3K/AKT, and WNT. In addition to the independent role of miR-532 in regulation of cellular processes, it also functions as a mediator of lncRNAs and circRNAs. Therefore, miR-532 can be considered as a non-invasive diagnostic/prognostic marker as well as a therapeutic target in cancer patients.

EAF2 Downregulation Recruits Tumor-associated Macrophages in Prostate Cancer through Upregulation of MIF

BACKGROUND

The role of tumor inflammatory microenvironment in the advancement of cancer, particularly prostate cancer, is widely acknowledged. ELL-associated factor 2 (EAF2), a tumor suppressor that has been identified in the prostate, is often downregulated in prostate cancer. Earlier investigations have shown that mice with EAF2 gene knockout exhibited a substantial infiltration of inflammatory cells into the prostatic stroma.

METHODS

A cohort comprising 38 patients who had been diagnosed with prostate cancer and subsequently undergone radical prostatectomy (RP) was selected. These patients were pathologically graded according to the Gleason scoring system and divided into two groups. The purpose of this selection was to investigate the potential correlation between EAF2 and CD163 using immunohistochemistry (IHC) staining. Additionally, in vitro experimentation was conducted to verify the relationship between EAF2 expression, macrophage migration and polarization.

RESULTS

Our study demonstrated that in specimens of human prostate cancer, the expression of EAF2 was notably downregulated, and this decrease was inversely associated with the number of CD163-positive macrophages that infiltrated the cancerous tissue. Cell co-culture experiments revealed that the chemotactic effect of tumor cells towards macrophages was intensified and that macrophages differentiated into tumor-associated macrophages (TAMs) when EAF2 was knocked out. Additionally, the application of cytokine protein microarray showed that the expression of chemokine macrophage migration inhibitory factor (MIF) increased after EAF2 knockout.

CONCLUSIONS

Our findings suggested that EAF2 was involved in the infiltration of CD163-positive macrophages in prostate cancer via MIF.

IRF5 suppresses metastasis through the regulation of tumor-derived extracellular vesicles and pre-metastatic niche formation

Metastasis is driven by extensive cooperation between a tumor and its microenvironment, resulting in the adaptation of molecular mechanisms that evade the immune system and enable pre-metastatic niche (PMN) formation. Little is known of the tumor-intrinsic factors that regulate these mechanisms. Here we show that expression of the transcription factor interferon regulatory factor 5 (IRF5) in osteosarcoma (OS) and breast carcinoma (BC) clinically correlates with prolonged survival and decreased secretion of tumor-derived extracellular vesicles (t-dEVs). Conversely, loss of intra-tumoral IRF5 establishes a PMN that supports metastasis. Mechanistically, IRF5-positive tumor cells retain IRF5 transcripts within t-dEVs that contribute to altered composition, secretion, and trafficking of t-dEVs to sites of metastasis. Upon whole-body pre-conditioning with t-dEVs from IRF5-high or -low OS and BC cells, we found increased lung metastatic colonization that replicated findings from orthotopically implanted cancer cells. Collectively, our findings uncover a new role for IRF5 in cancer metastasis through its regulation of t-dEV programming of the PMN.

Non-Coding RNA in Tumor Cells and Tumor-Associated Myeloid Cells-Function and Therapeutic Potential

The RNA world is wide, and besides mRNA, there is a variety of other RNA types, such as non-coding (nc)RNAs, which harbor various intracellular regulatory functions. This review focuses on small interfering (si)RNA and micro (mi)RNA, which form a complex network regulating mRNA translation and, consequently, gene expression. In fact, these RNAs are critically involved in the function and phenotype of all cells in the human body, including malignant cells. In cancer, the two main targets for therapy are dysregulated cancer cells and dysfunctional immune cells. To exploit the potential of mi- or siRNA therapeutics in cancer therapy, a profound understanding of the regulatory mechanisms of RNAs and following targeted intervention is needed to re-program cancer cells and immune cell functions in vivo. The first part focuses on the function of less well-known RNAs, including siRNA and miRNA, and presents RNA-based technologies. In the second part, the therapeutic potential of these technologies in treating cancer is discussed, with particular attention on manipulating tumor-associated immune cells, especially tumor-associated myeloid cells.

Comprehensive Molecular Analyses of an M2-Like Tumor-Associated Macrophage for Predicting the Prognosis and Immunotherapy in Breast Cancer

The involvement of M2-like tumor-associated macrophages (TAMs) in the advancement and treatment of cancer has been widely documented. This study aimed to develop a new signature associated with M2-like TAMs to predict the prognosis and treatment response in individuals diagnosed with breast cancer (BC). Weighted gene co-expression network analysis (WGCNA) was used to identity for M2-like TAM-related modular genes. The M2-like TAM-related modular subtype was identified using unsupervised clustering. WGCNA identified 722 M2-like TAM genes, 204 of which were associated with recurrence-free survival (RFS). Patients in cluster 1 exhibited upregulated cancer-related pathways, a higher proportion of triple-negative breast cancer (TNBC) subtypes, lower expression of immune checkpoints, and worse prognosis. Cluster 2 was characterized by upregulated immune-related pathways, a higher proportion of luminal A subtypes, and higher expression of immune checkpoints. A prognostic signature was created and confirmed using an independent dataset. A well-built nomogram can accurately forecast the survival outcomes for every individual. Furthermore, patients classified as low-risk exhibited a more favorable outlook, elevated tumor microenvironment (TME) score, and superior reaction to immunotherapy. In conclusion, we discovered 2 different types of M2-like TAMs and developed a prognostic signature revealing the diversity of M2-like TAMs in BC and their correlation with immune status and prognosis. This feature can predict the prognosis and immunotherapeutic effects of BC and offer novel concepts and approaches for tailoring BC treatment.

A pan-allelic human SIRPα-blocking antibody, ES004-B5, promotes tumor killing by enhancing macrophage phagocytosis and subsequently inducing an effective T-cell response

As a major immune cell type in the tumor microenvironment, tumor-associated macrophages secrete suppressive factors that can inhibit antitumor immunity and promote tumor progression. One approach trying to utilize macrophages for immunotherapy has been to block the CD47-SIRPα axis, which mediates inhibitory signaling, to promote phagocytosis of tumor cells. Many CD47-targeted agents, namely, anti-CD47 antibodies and SIRPα fusion proteins, were associated with a diverse spectrum of toxicities that limit their use in clinical settings. Universal expression of CD47 also leads to a severe "antigen sink" effect of CD47-targeted agents. Given that the CD47 receptor, SIRPα, has a more restricted expression profile and may have CD47-independent functions, targeting SIRPα is considered to have distinct advantages in improving clinical efficacy with a better safety profile. We have developed ES004-B5, a potentially best-in-class pan-allelic human SIRPα-blocking antibody using hybridoma technology. ES004-B5 binds to major human SIRPα variants through a unique epitope with high affinity. By blocking CD47-induced inhibitory "don't-eat-me" signaling, ES004-B5 exerts superior antitumor activity in combination with anti-tumor-associated antigen antibodies in vitro and in vivo. Unlike CD47-targeted agents, ES004-B5 exhibits an excellent safety profile in nonhuman primates. ES004-B5 has potential to be an important backbone for SIRPα-based combination therapy and/or bispecific antibodies, which will likely overcome the limitations of CD47-targeted agents encountered in clinical settings.

Rapamycin circumvents anti PD-1 therapy resistance in colorectal cancer by reducing PD-L1 expression and optimizing the tumor microenvironment

The unresectable or postoperative recurrence of advanced metastatic colorectal cancer (CRC) is the difficulty of its clinical management, and pharmacological therapy is the main source of benefit. Immune checkpoint inhibitors are therapeutic options but are effective in approximately 5 % of patients with deficient mismatch repair (MMR)/microsatellite instability CRC and are ineffective in patients with MMR-proficient (pMMR)/microsatellite stable (MSS) CRCs, which may be associated with the tumor microenvironment (TME). Here, we propose a new combination strategy and evaluate the efficacy of rapamycin (Rapa) combined with anti-PD-1 (αPD-1) in CT26 tumor-bearing mice, azoxymethane (AOM)/dextran sodium sulfate (DSS) inflammation-associated CRC mice, CT26-Luc tumor-bearing mice with postoperative recurrence, and CT26 liver metastasis mice. The results revealed that Rapa improved the therapeutic effect of αPD-1 and effectively inhibited colorectal carcinogenesis, postoperative recurrence, and liver metastasis. Mechanistically, Rapa improved the anticancer effect of αPD-1, associated with Rapa reprograming of the immunosuppressive TME. Rapa effectively depleted α-SMA+ cancer-associated fibroblasts and degraded collagen in the tumor tissue, increasing T lymphocyte infiltration into the tumor tissue. Rapa induced the downregulation of programed cell death 1 ligand 1 (PD-L1) protein and transcript levels in CT26 cells, which may be associated with the inhibition of the mTOR/P70S6K signaling axis. Furthermore, co-culture of tumor cells and CD8+ T lymphocytes demonstrated that Rapa-induced PD-L1 downregulation in tumor cells increased spleen-derived CD8+ T lymphocyte activation. Therefore, Rapa improves the anti-tumor effect of αPD-1 in CRCs, providing new ideas for its use to improve combinatorial strategies for anti-PD-1 immunotherapy.

Amino acid metabolic reprogramming in the tumor microenvironment and its implication for cancer therapy

Amino acids are essential building blocks for proteins, crucial energy sources for cell survival, and key signaling molecules supporting the resistant growth of tumor cells. In tumor cells, amino acid metabolic reprogramming is characterized by the enhanced uptake of amino acids as well as their aberrant synthesis, breakdown, and transport, leading to immune evasion and malignant progression of tumor cells. This article reviews the altered amino acid metabolism in tumor cells and its impact on tumor microenvironment, and also provides an overview of the current clinical applications of amino acid metabolism. Innovative drugs targeting amino acid metabolism hold great promise for precision and personalized cancer therapy.