Tumor-Associated Macrophage Status in Cancer Treatment

The role of IGFBP-3 in tumor development and progression: enlightenment for diagnosis and treatment

IGFBP-3 is aberrantly expressed in many tumor types, and its serum and tumor tissue levels provide auxiliary information for assessing the degree of tumor malignancy and patient prognosis, making it a potential therapeutic target for human malignancies and conferring it remarkable clinical value for determining patient prognosis. In this review, we provide a comprehensive overview of the aberrant expression, diverse biological effects, and clinical implications of IGFBP-3 in tumors and its role as a potential prognostic marker and therapeutic target for tumors. In addition, we summarize the signaling pathways through which IGFBP-3 exerts its effects. IGFBP-3 comprises an N-terminal, an intermediate region, and a C-terminal structural domain, each exerting different biological effects in several tumor cell types in an IGF-dependent/non-independent manner. IGFBP-3 shares an intricate relationship with the tumor microenvironment, thereby affecting tumor growth. Overall, IGFBP-3 is an essential regulatory factor that mediates tumor occurrence and progression. Gaining deeper insights into the fundamental characteristics of IGFBP-3 and its role in various tumor types will provide new perspectives and allow for the development of novel strategies for cancer diagnosis, treatment, and prognostic evaluation.

The role of tumor-associated macrophages in tumor immune evasion

BACKGROUND

Tumor growth is closely linked to the activities of various cells in the tumor microenvironment (TME), particularly immune cells. During tumor progression, circulating monocytes and macrophages are recruited, altering the TME and accelerating growth. These macrophages adjust their functions in response to signals from tumor and stromal cells. Tumor-associated macrophages (TAMs), similar to M2 macrophages, are key regulators in the TME.

METHODS

We review the origins, characteristics, and functions of TAMs within the TME. This analysis includes the mechanisms through which TAMs facilitate immune evasion and promote tumor metastasis. Additionally, we explore potential therapeutic strategies that target TAMs.

RESULTS

TAMs are instrumental in mediating tumor immune evasion and malignant behaviors. They release cytokines that inhibit effector immune cells and attract additional immunosuppressive cells to the TME. TAMs primarily target effector T cells, inducing exhaustion directly, influencing activity indirectly through cellular interactions, or suppressing through immune checkpoints. Additionally, TAMs are directly involved in tumor proliferation, angiogenesis, invasion, and metastasis. Developing innovative tumor-targeted therapies and immunotherapeutic strategies is currently a promising focus in oncology. Given the pivotal role of TAMs in immune evasion, several therapeutic approaches have been devised to target them. These include leveraging epigenetics, metabolic reprogramming, and cellular engineering to repolarize TAMs, inhibiting their recruitment and activity, and using TAMs as drug delivery vehicles. Although some of these strategies remain distant from clinical application, we believe that future therapies targeting TAMs will offer significant benefits to cancer patients.

Blocking the MIF-CD74 axis augments radiotherapy efficacy for brain metastasis in NSCLC via synergistically promoting microglia M1 polarization

BACKGROUND

Brain metastasis is one of the main causes of recurrence and death in non-small cell lung cancer (NSCLC). Although radiotherapy is the main local therapy for brain metastasis, it is inevitable that some cancer cells become resistant to radiation. Microglia, as macrophages colonized in the brain, play an important role in the tumor microenvironment. Radiotherapy could activate microglia to polarize into both the M1 and M2 phenotypes. Therefore, searching for crosstalk molecules within the microenvironment that can specifically regulate the polarization of microglia is a potential strategy for improving radiation resistance.

METHODS

We used databases to detect the expression of MIF in NSCLC and its relationship with prognosis. We analyzed the effects of targeted blockade of the MIF/CD74 axis on the polarization and function of microglia during radiotherapy using flow cytometry. The mouse model of brain metastasis was used to assess the effect of targeted blockade of MIF/CD74 axis on the growth of brain metastasis.

RESULT

Our findings reveals that the macrophage migration inhibitory factor (MIF) was highly expressed in NSCLC and is associated with the prognosis of NSCLC. Mechanistically, we demonstrated CD74 inhibition reversed radiation-induced AKT phosphorylation in microglia and promoted the M1 polarization in combination of radiation. Additionally, blocking the MIF-CD74 interaction between NSCLC and microglia promoted microglia M1 polarization. Furthermore, radiation improved tumor hypoxia to decrease HIF-1α dependent MIF secretion by NSCLC. MIF inhibition enhanced radiosensitivity for brain metastasis via synergistically promoting microglia M1 polarization in vivo.

CONCLUSIONS

Our study revealed that targeting the MIF-CD74 axis promoted microglia M1 polarization and synergized with radiotherapy for brain metastasis in NSCLC.

Roles of reactive oxygen species in inflammation and cancer

Reactive oxygen species (ROS) constitute a spectrum of oxygenic metabolites crucial in modulating pathological organism functions. Disruptions in ROS equilibrium span various diseases, and current insights suggest a dual role for ROS in tumorigenesis and the immune response within cancer. This review rigorously examines ROS production and its role in normal cells, elucidating the subsequent regulatory network in inflammation and cancer. Comprehensive synthesis details the documented impacts of ROS on diverse immune cells. Exploring the intricate relationship between ROS and cancer immunity, we highlight its influence on existing immunotherapies, including immune checkpoint blockade, chimeric antigen receptors, and cancer vaccines. Additionally, we underscore the promising prospects of utilizing ROS and targeting ROS modulators as novel immunotherapeutic interventions for cancer. This review discusses the complex interplay between ROS, inflammation, and tumorigenesis, emphasizing the multifaceted functions of ROS in both physiological and pathological conditions. It also underscores the potential implications of ROS in cancer immunotherapy and suggests future research directions, including the development of targeted therapies and precision oncology approaches. In summary, this review emphasizes the significance of understanding ROS-mediated mechanisms for advancing cancer therapy and developing personalized treatments.

Recent Biomaterial-Assisted Approaches for Immunotherapeutic Inhibition of Cancer Recurrence

Biomaterials possess distinctive properties, notably their ability to encapsulate active biological products while providing biocompatible support. The immune system plays a vital role in preventing cancer recurrence, and there is considerable demand for an effective strategy to prevent cancer recurrence, necessitating effective strategies to address this concern. This review elucidates crucial cellular signaling pathways in cancer recurrence. Furthermore, it underscores the potential of biomaterial-based tools in averting or inhibiting cancer recurrence by modulating the immune system. Diverse biomaterials, including hydrogels, particles, films, microneedles, etc., exhibit promising capabilities in mitigating cancer recurrence. These materials are compelling candidates for cancer immunotherapy, offering in situ immunostimulatory activity through transdermal, implantable, and injectable devices. They function by reshaping the tumor microenvironment and impeding tumor growth by reducing immunosuppression. Biomaterials facilitate alterations in biodistribution, release kinetics, and colocalization of immunostimulatory agents, enhancing the safety and efficacy of therapy. Additionally, how the method addresses the limitations of other therapeutic approaches is discussed.

ZIF-8-Encapsulated Pexidartinib Delivery via Targeted Peptide-Modified M1 Macrophages Attenuates MDSC-Mediated Immunosuppression in Osteosarcoma

Adoptive cellular therapy is a promising strategy for cancer treatment. However, the effectiveness of this therapy is limited by its intricate and immunosuppressive tumor microenvironment. In this study, a targeted therapeutic strategy for macrophage loading of drugs is presented to enhance anti-tumor efficacy of macrophages. K7M2-target peptide (KTP) is used to modify macrophages to enhance their affinity for tumors. Pexidartinib-loaded ZIF-8 nanoparticles (P@ZIF-8) are loaded into macrophages to synergistically alleviate the immunosuppressive tumor microenvironment synergistically. Thus, the M1 macrophages decorated with KTP carried P@ZIF-8 and are named P@ZIF/M1-KTP. The tumor volumes in the P@ZIF/M1-KTP group are significantly smaller than those in the other groups, indicating that P@ZIF/M1-KTP exhibited enhanced anti-tumor efficacy. Mechanistically, an increased ratio of CD4+ T cells and a decreased ratio of MDSCs in the tumor tissues after treatment with P@ZIF/M1-KTP indicated that it can alleviate the immunosuppressive tumor microenvironment. RNA-seq further confirms the enhanced immune cell function. Consequently, P@ZIF/M1-KTP has great potential as a novel adoptive cellular therapeutic strategy for tumors.

HMGB1 in exosomes derived from gastric cancer cells induces M2-like macrophage polarization by inhibiting the NF-κB signaling pathway

Gastric cancer (GC) seriously threatens human health. High mobility group protein B1 (HMGB1) and M2-like macrophages are closely associated with core events about human cancers, such as invasion, and metastasis, and cancer microenvironment. This study mainly determined the regulatory effect of HMGB1 in GC cell-derived exosomes on M2-like macrophage polarization as well as the underlying mechanism. HMGB1 was found to be highly expressed in gastric tissue specimens, which might lead to the poor prognosis of GC. High levels of HMGB1 were also observed in the plasma of GC patients, indicating the possibility that it regulates the immune microenvironment via exosomes. Further study revealed and confirmed the regulatory effect of exosomes derived from GC cells with high HMGB1 level on inducing M2-like macrophage polarization. Mechanistically, by interacting with the transcription factor POU2F1, exosomal HMGB1 inhibited the transcriptional activity of p50, resulting in the inactivation of NF-κB signaling pathway and thereby inducing M2-like macrophage polarization. Moreover, instead of promoting the proliferation of GC cells, exosomes with high HMGB1 levels induced M2-like macrophage polarization and promoted GC progression. This study reveals a novel mechanism by which HMGB1 promotes GC progression, which may provide new insights for improving the efficacy of cancer immunotherapy.

Targeting the macrophage immunocheckpoint: a novel insight into solid tumor immunotherapy

Tumor immunotherapy, which targets immune checkpoints, presents a promising strategy for the treatment of various cancer types. However, current clinical data indicate challenges in its application to solid tumors. Recent studies have revealed a significant correlation between the degree of immune response in immunotherapy and the tumor microenvironment, particularly with regard to tumor-infiltrating immune cells. Among these immune cells, macrophages, a critical component, are playing an increasingly vital role in tumor immunotherapy. This review focuses on elucidating the role of macrophages within solid tumors and provides an overview of the progress in immunotherapy approaches centered around modulating macrophage responses through various immune factors. Video Abstract.

Prognostic significance of annexin A2 and tumor associated macrophages (TAMs) in metastatic renal cell carcinoma and their relation to Sunitinib resistance

Sunitinib, an antiangiogenic tyrosine kinase inhibitor, is the main treatment for metastatic renal cell carcinoma (mRCC). Development of resistance is a major obstacle against therapy success. The aim of this study was to assess annexin A2 and CD163+ tumor associated macrophages (TAMs) immunohistochemical expression in 50 mRCC cases as regard to patients' prognosis and Sunitinib response. Also, to assess the correlation between annexin A2 and TAMs expression. High annexin A2 expression and TAMs density were associated with serum calcium level (P = 0.024 and 0.037, respectively), larger tumor size (P < 0.001), high tumor grade (P = 0.014 and <0.001, respectively), and the presence of tumor necrosis (P < 0.001). High annexin A2 and TAMs expressions were related to shorter patients' overall survival (P = 0.009 and 0.001, respectively) and progression-free survival (P = 0.003 and 0.001, respectively). Annexin A2 was correlated with TAMs density (r = 0.890). Annexin A2 and TAMs are associated with poor prognostic parameters in mRCC patients, including high nuclear grade, increased tumor size, and the presence of tumor necrosis, together with shorter patients' survivals and poor response to Sunitinib. Annexin A2 expression is correlated with TAMs density suggesting immunomodulatory role of annexin A2.

Tumor-Associated Macrophage Targeting of Nanomedicines in Cancer Therapy

The tumor microenvironment (TME) is pivotal in tumor growth and metastasis, aligning with the "Seed and Soil" theory. Within the TME, tumor-associated macrophages (TAMs) play a central role, profoundly influencing tumor progression. Strategies targeting TAMs have surfaced as potential therapeutic avenues, encompassing interventions to block TAM recruitment, eliminate TAMs, reprogram M2 TAMs, or bolster their phagocytic capabilities via specific pathways. Nanomaterials including inorganic materials, organic materials for small molecules and large molecules stand at the forefront, presenting significant opportunities for precise targeting and modulation of TAMs to enhance therapeutic efficacy in cancer treatment. This review provides an overview of the progress in designing nanoparticles for interacting with and influencing the TAMs as a significant strategy in cancer therapy. This comprehensive review presents the role of TAMs in the TME and various targeting strategies as a promising frontier in the ever-evolving field of cancer therapy. The current trends and challenges associated with TAM-based therapy in cancer are presented.

Immune Cells in the Tumor Microenvironment of Soft Tissue Sarcomas

Soft tissue sarcomas (STSs) are a rare heterogeneous group of malignant neoplasms characterized by their aggressive course and poor response to treatment. This determines the relevance of research aimed at studying the pathogenesis of STSs. By now, it is known that STSs is characterized by complex relationships between the tumor cells and immune cells of the microenvironment. Dynamic interactions between tumor cells and components of the microenvironment enhance adaptation to changing environmental conditions, which provides the high aggressive potential of STSs and resistance to antitumor therapy. Today, active research is being conducted to find effective antitumor drugs and to evaluate the possibility of using therapy with immune cells of STS. The difficulty in assessing the efficacy of new antitumor options is primarily due to the high heterogeneity of this group of malignant neoplasms. Studying the role of immune cells in the microenvironment in the progression STSs and resistance to antitumor therapies will provide the discovery of new biomarkers of the disease and the prediction of response to immunotherapy. In addition, it will help to initially divide patients into subgroups of good and poor response to immunotherapy, thus avoiding wasting precious time in selecting the appropriate antitumor agent.

Unraveling the enigma of tumor-associated macrophages: challenges, innovations, and the path to therapeutic breakthroughs

Tumor-associated macrophages (TAMs) are integral to the tumor microenvironment (TME), influencing cancer progression significantly. Attracted by cancer cell signals, TAMs exhibit unparalleled adaptability, aligning with the dynamic tumor milieu. Their roles span from promoting tumor growth and angiogenesis to modulating metastasis. While substantial research has explored the fundamentals of TAMs, comprehending their adaptive behavior, and leveraging it for novel treatments remains challenging. This review delves into TAM polarization, metabolic shifts, and the complex orchestration of cytokines and chemokines determining their functions. We highlight the complexities of TAM-targeted research focusing on their adaptability and potential variability in therapeutic outcomes. Moreover, we discuss the synergy of integrating TAM-focused strategies with established cancer treatments, such as chemotherapy, and immunotherapy. Emphasis is laid on pioneering methods like TAM reprogramming for cancer immunotherapy and the adoption of single-cell technologies for precision intervention. This synthesis seeks to shed light on TAMs' multifaceted roles in cancer, pinpointing prospective pathways for transformative research and enhancing therapeutic modalities in oncology.

Functional polarization of tumor-associated macrophages dictated by metabolic reprogramming

Macrophages are highly plastic in different tissues and can differentiate into functional subpopulations under different stimuli. Tumor-associated macrophages (TAMs) are one of the most important innate immune cells implicated in the establishment of an immunosuppressive tumor microenvironment (TME). Recent evidence pinpoints the critical role of metabolic reprogramming in dictating pro-tumorigenic functions of TAMs. Both tumor cells and macrophages undergo metabolic reprogramming to meet energy demands in the TME. Understanding the metabolic rewiring in TAMs can shed light on immune escape mechanisms and provide insights into repolarizing TAMs towards anti-tumorigenic function. Here, we discuss how metabolism impinges on the functional divergence of macrophages and its relevance to macrophage polarization in the TME.

Tumor-associated macrophages: Potential therapeutic targets and diagnostic markers in cancer

Macrophages are plastic and functionally diverse, present in all tissues, and play a key role in organisms from development, homeostasis and repair, to immune responses to pathogens. They are central to many disease states and have emerged as important therapeutic targets for many diseases. Tumor-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment (TME) and are key factors influencing cancer progression, metastasis and tumor recurrence. TAMs can be derived from different sources and exert different pro- or anti-tumor effects based on the type, stage and immune composition of the tumor. TAMs are highly heterogeneous and diverse, and have multiple functional phenotypes. There is still a great deal of controversy regarding the relationship between TAMs and prognosis of cancer patients. In this review, we summarize the characteristics of common markers of TAMs as well as explore the prognostic role of TAMs in different cancers including lung, breast, gastric, colorectal, esophageal and ovarian cancers.

Macrophages as Promising Carriers for Nanoparticle Delivery in Anticancer Therapy

Macrophages play a critical role in the immune response due to their ability to recognize and remove pathogens, as well as present antigens, which are involved in inflammation, but they are also one of the most abundant immune cell populations present in the tumor microenvironment. In recent years, macrophages have become promising cellular carriers for drug and nanoparticle delivery to the tumor microenvironment, mainly due to their natural properties such as biocompatibility, degradability, lack of immunogenicity, long half-life in circulation, crossing biological barriers, and the possibility of migration and accumulation at a site of inflammation such as a tumor. For the effectiveness of this therapeutic strategy, known as "Trojan horse", it is important that the nanoparticles engulfed by macrophages do not affect their proper functioning. In our review, we discussed how the size, shape, chemical and mechanical properties of nanoparticles influence their internalization by macrophages. In addition, we described the promising research utilizing macrophages, their cell membranes and macrophage-derived exosomes as drug carriers in anticancer therapy. As a prospect of the wider use of this therapeutic strategy, we postulate its future application in boron delivery to the tumor environment in boron neutron capture therapy.

Multifunctional Redox-Responsive Nanoplatform with Dual Activation of Macrophages and T Cells for Antitumor Immunotherapy

High expression of programmed death ligand 1 (PD-L1) and strong immune evasion ability of the tumor microenvironment (TME) are maintained through mutual regulation between different immune and stromal cells, which causes obstructions for cancer immunotherapy, especially immunosuppressive M2-like phenotype tumor-associated macrophages (TAMs). Repolarization of TAMs to the M1-like phenotype could secrete proinflammatory cytokines and reverse the immunosuppressive state of the TME. However, we found that reactive oxygen species (ROS) generated by repolarized TAMs could be a double-edged sword: ROS cause a stronger suppressive effect on CD8 T cells through an increased proportion of apoptotic regulatory T (Treg) cells. Thus, simply repolarizing TAMs while ignoring the suppressed function of T cells is insufficient for generating adequate antitumor immunity. Accordingly, we engineered multifunctional redox-responsive nanoplatform NPs (M+C+siPD-L1) with Toll-like receptor agonist (M), catalase (C), and siPD-L1 encased for coregulation of both TAMs and T cells to maximize cancer immunotherapy. Our results demonstrated that NPs (M+C+siPD-L1) showed superior biocompatibility and intratumor accumulation. For in vitro experiments, NPs (M+C+siPD-L1) simultaneously repolarized TAMs to the M1-like phenotype, hydrolyzed extra ROS, knocked down the expression of PD-L1 on tumor cells, and rescued the function of CD8 T cells suppressed by Treg cells. In both orthotopic Hepa1-6 and 4T1 tumor-bearing mouse models, NPs (M+C+siPD-L1) could effectively evoke active systemic antitumor immunity and inhibit tumor growth. The combination of repolarizing TAMs, hydrolyzing extra ROS, and knocking down the expression of PD-L1 proves to be a synergistic approach in cancer immunotherapy.

miR-210 promotes hepatocellular carcinoma progression by modulating macrophage autophagy through PI3K/AKT/mTOR signaling

BACKGROUND

Tumor-associated macrophages (TAMs) play an important role in tumor development. Increasing research suggests that miR-210 may promote the progression of tumor virulence, but whether its pro-carcinogenic effect in primary hepatocellular carcinoma (HCC) is via an action on M2 macrophages has not been examined.

METHODS

Differentiation of THP-1 monocytes into M2-polarized macrophages was induced with phorbol myristate acetate (PMA) and IL-4, IL-13. M2 macrophages were transfected with miR-210 mimics or miR-210 inhibitors. Flow cytometry was used to identify macrophage-related markers and apoptosis levels. The autophagy level of M2 macrophages, expression of PI3K/AKT/mTOR signaling pathway-related mRNAs and protein were detected by qRT-PCR and Western blot. HepG2 and MHCC-97H HCC cell lines were cultured with M2 macrophages conditioned medium to explore the effects of M2 macrophage-derived miR-210 on the proliferation, migration, invasion and apoptosis of HCC cells.

RESULTS

qRT-PCR showed increased expression of miR-210 in M2 macrophages. Autophagy-related gene and protein expression was enhanced in M2 macrophages transfected with miR-210 mimics, while apoptosis-related proteins were decreased. MDC staining and transmission electron microscopy observed the accumulation of MDC-labeled vesicles and autophagosomes in M2 macrophages in the miR-210 mimic group. The expression of PI3K/AKT/mTOR signaling pathway in M2 macrophages was reduced in miR-210 mimic group. HCC cells co-cultured with M2 macrophages transfected with miR-210 mimics exhibited enhanced proliferation and invasive ability as compared to the control group, while apoptosis levels were reduced. Moreover, promoting or inhibiting autophagy could enhance or abolish the above observed biological effects, respectively.

CONCLUSIONS

miR-210 can promote autophagy of M2 macrophages via PI3K/AKT/mTOR signaling pathway. M2 macrophage-derived miR-210 promotes the malignant progression of HCC via autophagy, suggesting that macrophage autophagy may serve as a new therapeutic target for HCC, and targeting miR-210 may reset the effect of M2 macrophages on HCC.

The NR_109/FUBP1/c-Myc axis regulates TAM polarization and remodels the tumor microenvironment to promote cancer development

BACKGROUND

Tumor-associated macrophages (TAMs) are a major component of the tumor microenvironment (TME) and exert an important role in tumor progression. Due to the heterogeneity and plasticity of TAMs, modulating the polarization states of TAMs is considered as a potential therapeutic strategy for tumors. Long noncoding RNAs (lncRNAs) have been implicated in various physiological and pathological processes, yet the underlying mechanism on how lncRNAs manipulate the polarization states of TAMs is still unclear and remains to be further investigated.

METHODS

Microarray analyses were employed to characterize the lncRNA profile involved in THP-1-induced M0, M1 and M2-like macrophage. Among those differentially expressed lncRNAs, NR_109 was further studied, for its function in M2-like macrophage polarization and the effects of the condition medium or macrophages mediated by NR_109 on tumor proliferation, metastasis and TME remodeling both in vitro and in vivo. Moreover, we revealed how NR_109 interacted with far upstream element-binding protein 1 (FUBP1) to regulate the protein stability through hindering ubiquitination modification by competitively binding with JVT-1. Finally, we examined sections of tumor patients to probe the correlation among the expression of NR_109 and related proteins, showing the clinical significance of NR_109.

RESULTS

We found that lncRNA NR_109 was highly expressed in M2-like macrophages. Knockdown NR_109 impeded IL-4 induced M2-like macrophage polarization and significantly reduced the activity of M2-like macrophages to support the proliferation and metastasis of tumor cells in vitro and in vivo. Mechanistically, NR_109 competed with JVT-1 to bind FUBP1 at its C-terminus domain, impeded the ubiquitin-mediated degradation of FUBP1, activated c-Myc transcription and thus promoted M2-like macrophages polarization. Meanwhile, as a transcription factor, c-Myc could bind to the promoter of NR_109 and enhance the transcription of NR_109. Clinically, high NR_109 expression was found in CD163⁺ TAMs from tumor tissues and was positively correlated with poor clinical stages of patients with gastric cancer and breast cancer.

CONCLUSIONS

Our work revealed for the first time that NR_109 exerted a crucial role in regulating the phenotype-remodeling and function of M2-like macrophages via a NR_109/FUBP1/c-Myc positive feedback loop. Thus, NR_109 has great translational potentials in the diagnosis, prognosis and immunotherapy of cancer.

Tumor-associated macrophages induce inflammation and drug resistance in a mechanically tunable engineered model of osteosarcoma

The tumor microenvironment is a complex and dynamic ecosystem composed of various physical cues and biochemical signals that facilitate cancer progression, and tumor-associated macrophages are especially of interest as a treatable target due to their diverse pro-tumorigenic functions. Engineered three-dimensional models of tumors more effectively mimic the tumor microenvironment than monolayer cultures and can serve as a platform for investigating specific aspects of tumor biology within a controlled setting. To study the combinatorial effects of tumor-associated macrophages and microenvironment mechanical properties on osteosarcoma, we co-cultured human osteosarcoma cells with macrophages within biomaterials-based bone tumor niches with tunable stiffness. In the first 24 h of direct interaction between the two cell types, macrophages induced an inflammatory environment consisting of high concentrations of tumor necrosis factor alpha (TNFα) and interleukin (IL)-6 within moderately stiff scaffolds. Expression of Yes-associated protein (YAP), but not its homolog, transcriptional activator with PDZ-binding motif (TAZ), in osteosarcoma cells was significantly higher than in macrophages, and co-culture of the two cells slightly upregulated YAP in both cells, although not to a significant degree. Resistance to doxorubicin treatment in osteosarcoma cells was correlated with inflammation in the microenvironment, and signal transducer and activator of transcription 3 (STAT3) inhibition diminished the inflammation-related differences in drug resistance but ultimately did not improve the efficacy of doxorubicin. This work highlights that the biochemical cues conferred by tumor-associated macrophages in osteosarcoma are highly variable, and signals derived from the immune system should be considered in the development and testing of novel drugs for cancer.

Role of tumor-associated macrophages in common digestive system malignant tumors

Many digestive system malignant tumors are characterized by high incidence and mortality rate. Increasing evidence has revealed that the tumor microenvironment (TME) is involved in cancer initiation and tumor progression. Tumor-associated macrophages (TAMs) are a predominant constituent of the TME, and participate in the regulation of various biological behaviors and influence the prognosis of digestive system cancer. TAMs can be mainly classified into the antitumor M1 phenotype and protumor M2 phenotype. The latter especially are crucial drivers of tumor invasion, growth, angiogenesis, metastasis, immunosuppression, and resistance to therapy. TAMs are of importance in the occurrence, development, diagnosis, prognosis, and treatment of common digestive system malignant tumors. In this review, we summarize the role of TAMs in common digestive system malignant tumors, including esophageal, gastric, colorectal, pancreatic and liver cancers. How TAMs promote the development of tumors, and how they act as potential therapeutic targets and their clinical applications are also described.

Current Landscape of Immunotherapy for Advanced Sarcoma

There is substantial heterogeneity between different subtypes of sarcoma regarding their biological behavior and microenvironment, which impacts their responsiveness to immunotherapy. Alveolar soft-part sarcoma, synovial sarcoma and undifferentiated pleomorphic sarcoma show higher immunogenicity and better responses to checkpoint inhibitors. Combination strategies adding immunotherapy to chemotherapy and/or tyrosine-kinase inhibitors globally seem superior to single-agent schemes. Therapeutic vaccines and different forms of adoptive cell therapy, mainly engineered TCRs, CAR-T cells and TIL therapy, are emerging as new forms of immunotherapy for advanced solid tumors. Tumor lymphocytic infiltration and other prognostic and predictive biomarkers are under research.

Mutant p53 and NOX4 are modulators of a CCL5-driven pro-migratory secretome

Previously, we showed wild-type (WT) and mutant (mt) forms of p53 differentially regulate ROS generation by NADPH oxidase-4 (NOX4). We found that WT-p53 suppresses TGF-β-induced NOX4, ROS production, and cell migration, whereas tumor-associated mt-p53 proteins enhance NOX4 expression and cell migration by TGF-β/SMAD3-dependent mechanisms. In this study, we investigated the role of mutant p53-induced NOX4 on the cancer cell secretome and the effects NOX4 signaling have on the tumor microenvironment (TME). We found conditioned media collected from H1299 lung epithelial cells stably expressing either mutant p53-R248Q or R273H promotes the migration and invasion of naïve H1299 cells and chemotactic recruitment of THP-1 monocytes. These effects were diminished with conditioned media from cells co-transfected with dominant negative NOX4 (P437H). We utilized immunoblot-based cytokine array analysis to identify factors in mutant p53 H1299 cell conditioned media that promote cell migration and invasion. We found CCL5 was significantly reduced in conditioned media from H1299 cells co-expressing p53-R248Q and dominant negative NOX4. Moreover, neutralization of CCL5 reduced autocrine-mediated H1299 cell mobility. Furthermore, CCL5 and TGF-beta from M2-polarized macrophages have a significant role in crosstalk and H1299 cell migration and invasion. Collectively, our findings provide further insight into NOX4-based communication in the tumor microenvironment and its potential as a therapeutic target affecting metastatic disease progression.

The role of macrophages in the tumor microenvironment and tumor metabolism

The complexity and plasticity of the tumor microenvironment (TME) make it difficult to fully understand the intratumoral regulation of different cell types and their activities. Macrophages play a crucial role in the signaling dynamics of the TME. Among the different subtypes of macrophages, tumor-associated macrophages (TAMs) are often associated with poor prognosis, although some subtypes of TAMs can at the same time improve treatment responsiveness and lead to favorable clinical outcomes. TAMs are key regulators of cancer cell proliferation, metastasis, angiogenesis, extracellular matrix remodeling, tumor metabolism, and importantly immunosuppression in the TME by modulating various chemokines, cytokines, and growth factors. TAMs have been identified as a key contributor to resistance to chemotherapy and cancer immunotherapy. In this review article, we aim to discuss the mechanisms by which TAMs regulate innate and adaptive immune signaling in the TME and summarize recent preclinical research on the development of therapeutics targeting TAMs and tumor metabolism.

A positive feedback loop driven by fibronectin and IL-1β sustains the inflammatory microenvironment in breast cancer

Inflammatory alterations of the extracellular matrix shape the tumor microenvironment and promote all stages of carcinogenesis. This study aims to determine the impact of cellular fibronectin on inflammatory facets of tumor-associated macrophages (TAMs) in breast cancer. Cellular fibronectin (FN) harboring the alternatively spliced extra domain A (FN-EDA) was determined to be a matrix component produced by the triple-negative breast cancer (TNBC) cells. High levels of FN-EDA correlated with poor survival in breast cancer patients. The proinflammatory cytokine IL-1β enhanced the expression of cellular fibronectin including FN-EDA. TAMs were frequently observed in the tumor areas rich in FN-EDA. Conditioned media from TNBC cells induced the differentiation of CD206⁺CD163⁺ macrophages and stimulated the STAT3 pathway, ex vivo. In the macrophages, the STAT3 pathway enhanced FN-EDA-induced IL-1β secretion and NF-κB signaling. In conclusion, our data indicate a self-reinforcing mechanism sustained by FN-EDA and IL-1β through NF-κB and STAT3 signaling in TAMs which fosters an inflammatory environment in TNBC.

TYRO3 blockade enhances anti-PD-1 therapy response by modulating expression of CCN1 in tumor microenvironment

BACKGROUND

Immunological contexture differs across malignancies, and understanding it in the tumor microenvironment (TME) is essential for development of new anticancer agents in order to achieve synergistic effects with anti-programmed cell death protein-1 (PD-1) therapy. TYRO3, AXL, and MERTK receptors are bi-expressed in both cancer and immune cells, and thus emerge as promising targets for therapeutic intervention. Whereas AXL and MERTK have been extensively studied, the role of TYRO3, in the TME, is still undetermined.

METHODS

Here, we screened the TYRO3-focused chemical library consisting of 208 compounds and presented a potent and highly selective TYRO3 inhibitor, KRCT87. We explored the role of TYRO3 using mouse engrafting MC38 or 4T1 tumors. We validated the results using flow cytometry, RNA sequencing analysis, gene knockdown or overexpression, ex vivo immune cells isolation from mouse models, immunoblotting and quantitative PCR. Flow cytometry was used for the quantification of cell populations and immunophenotyping of macrophages and T cells. Co-cultures of macrophages and T cells were performed to verify the role of CCN1 in the tumors.

RESULTS

TYRO3 blockade boosts antitumor immune responses in both the tumor-draining lymph nodes and tumors in MC38-syngeneic mice models. Moreover, the combination of KRCT87 and anti-PD-1 therapy exerts significant synergistic antitumor effects in anti-PD-1-non-responsive 4T1-syngeneic model. Mechanistically, we demonstrated that inhibition of TYRO3-driven CCN1 secretion fosters macrophages into M1-skewing phenotypes, thereby triggering antitumor T-cell responses. CCN1 overexpression in MC38 tumors diminishes responsiveness to anti-PD-1 therapy.

CONCLUSIONS

The activated TYRO3-CCN1 axis in cancer could dampen anti-PD-1 therapy responses. These findings highlight the potential of TYRO3 blockade to improve the clinical outcomes of anti-PD-1 therapy.

Macrophage numbers in the marginal area of sarcomas predict clinical prognosis

Even when treated comprehensively by surgery, chemotherapy, and radiotherapy, soft-tissue sarcoma has an unfavorable outcome. Because soft-tissue sarcoma is rare, it is the subject of fewer clinicopathological studies, which are important for clarifying pathophysiology. Here, we examined tumor-associated macrophages in the intratumoral and marginal areas of sarcomas to increase our knowledge about the pathophysiology. Seventy-five sarcoma specimens (not limited to a single histological type), resected at our institution, were collected, and the number of CD68-, CD163-, and CD204-positive macrophages in the intratumoral and marginal areas was counted. We then performed statistical analysis to examine links between macrophage numbers, clinical factors, and outcomes. A high number of macrophages positive for all markers in both areas was associated with worse disease-free survival (DFS). Next, we divided cases according to the FNCLCC classification (Grade 1 and Grades 2/3). In the Grade 1 group, there was no significant association between macrophage number and DFS. However, in the Grade 2/3 group, high numbers of CD163- and CD204-positive macrophages in the marginal area were associated with poor DFS. By contrast, there was no significant difference between the groups with respect to high or low numbers of CD68-, CD163-, or CD204-positive macrophages in the intratumoral area. Multivariate analysis identified the number of CD163- and CD204-positive macrophages in the marginal area as an independent prognostic factor. Macrophage numbers in the marginal area of soft-tissue sarcoma may better reflect clinical behavior.

Construction and validation of a bladder cancer risk model based on autophagy-related genes

Autophagy has an important association with tumorigenesis, progression, and prognosis. However, the mechanism of autophagy-regulated genes on the risk prognosis of bladder cancer (BC) patients has not been fully elucidated yet. In this study, we created a prognostic model of BC risk based on autophagy-related genes, which further illustrates the value of genes associated with autophagy in the treatment of BC. We first downloaded human autophagy-associated genes and BC datasets from Human Autophagy Database and The Cancer Genome Atlas (TCGA) database, and finally obtained differential prognosis-associated genes for autophagy by univariate regression analysis and differential analysis of cancer versus normal tissues. Subsequently, we downloaded two datasets from Gene Expression Omnibus (GEO), GSE31684 and GSE15307, to expand the total number of samples. Based on these genes, we distinguished the molecular subtypes (C1, C2) and gene classes (A, B) of BC by consistent clustering analysis. Using the genes merged from TCGA and the two GEO datasets, we conducted least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analysis to obtain risk genes and construct autophagy-related risk prediction models. The accuracy of this risk prediction model was assessed by receiver operating characteristic (ROC) and calibration curves, and then nomograms were constructed to predict the survival of bladder cancer patients at 1, 3, and 5 years, respectively. According to the median value of the risk score, we divided BC samples into the high- and low-risk groups. Kaplan-Meier (K-M) survival analysis was performed to compare survival differences between subgroups. Then, we used single sample gene set enrichment analysis (ssGSEA) for immune cell infiltration abundance, immune checkpoint genes, immunotherapy response, gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis, and tumor mutation burden (TMB) analysis for different subgroups. We also applied quantitative real-time polymerase chain reaction (PCR) and immunohistochemistry (IHC) techniques to verify the expression of these six genes in the model. Finally, we chose the IMvigor210 dataset for external validation. Six risk genes associated with autophagy (SPOCD1, FKBP10, NAT8B, LDLR, STMN3, and ANXA2) were finally screened by LASSO regression algorithm and multivariate Cox regression analysis. ROC and calibration curves showed that the model established was accurate and reliable. Univariate and multivariate regression analyses were used to verify that the risk model was an independent predictor. K-M survival analysis indicated that patients in the high-risk group had significantly worse overall survival than those in the low-risk group. Analysis by algorithms such as correlation analysis, gene set variation analysis (GSVA), and ssGSEA showed that differences in immune microenvironment, enrichment of multiple biologically active pathways, TMB, immune checkpoint genes, and human leukocyte antigens (HLAs) were observed in the different risk groups. Then, we constructed nomograms that predicted the 1-, 3-, and 5-year survival rates of different BC patients. In addition, we screened nine sensitive chemotherapeutic drugs using the correlation between the obtained expression status of risk genes and drug sensitivity results. Finally, the external dataset IMvigor210 verified that the model is reliable and efficient. We established an autophagy-related risk prognostic model that is accurate and reliable, which lays the foundation for future personalized treatment of bladder cancer.

Epigenetic remodeling of the immune landscape in cancer: therapeutic hurdles and opportunities

The tumor immune microenvironment represents a sophisticated ecosystem where various immune cell subtypes communicate with cancer cells and stromal cells. The dynamic cellular composition and functional characteristics of the immune landscape along the trajectory of cancer development greatly impact the therapeutic efficacy and clinical outcome in patients receiving systemic antitumor therapy. Mounting evidence has suggested that epigenetic mechanisms are the underpinning of many aspects of antitumor immunity and facilitate immune state transitions during differentiation, activation, inhibition, or dysfunction. Thus, targeting epigenetic modifiers to remodel the immune microenvironment holds great potential as an integral part of anticancer regimens. In this review, we summarize the epigenetic profiles and key epigenetic modifiers in individual immune cell types that define the functional coordinates of tumor permissive and non-permissive immune landscapes. We discuss the immunomodulatory roles of current and prospective epigenetic therapeutic agents, which may open new opportunities in enhancing cancer immunotherapy or overcoming existing therapeutic challenges in the management of cancer.

A composite score based on immune-related gene prognostic index and m6A risk score of head and neck squamous cell carcinoma

Background: Immunotherapy has been demonstrated favorable in head and neck squamous cell carcinoma (HNSCC). Studies indicated that immune-related gene prognostic index (IRGPI) was a robust signature, and N⁶-methyladenosine (m⁶A) methylation had a significant impact on the tumor immune microenvironment (TIME) and immunotherapy of head and neck squamous cell carcinoma. Thus, combining indicated that immune-related gene prognostic index with m⁶A status should offer a better predictive power for immune responses. Methods: Head and neck squamous cell carcinoma samples from the cancer genome atlas (TCGA, n = 498) and gene expression omnibus database (GSE65858, n = 270) were used in this study. Cox regression analysis was used to construct the indicated that immune-related gene prognostic index through immune-related hub genes which were identified by weighted gene co-expression network analysis (WGCNA). The m⁶A risk score was constructed by least absolute shrinkage and selection operator (LASSO) regression analysis. Principal component analysis was used to construct a composite score, and systematically correlate subgroups according to tumor immune microenvironment cell-infiltrating characteristics. Results: A composite score was determined based on indicated that immune-related gene prognostic index and m⁶A risk score. Head and neck squamous cell carcinoma patients in the cancer genome atlas were divided into four subgroups: A (IRGPI-High&m⁶A-risk-High, n = 127), B (IRGPI-High&m⁶A-risk-Low, n = 99), C (IRGPI-Low&m⁶A-risk-High, n = 99), and D (IRGPI-Low&m⁶A-risk-Low, n = 128), and overall survival (OS) was significantly different between subgroups (p < 0.001). The characteristics of tumor immune microenvironment cell infiltration in the four subgroups were significantly different in subgroups (p < 0.05). The receiver operating characteristic (ROC) curves show the predictive value of composite score for overall survival was superior to other scores. Conclusion: The composite score is a promising prognostic signature which might distinguish immune and molecular characteristics, predict prognosis, and guide more effective immunotherapeutic strategies for head and neck squamous cell carcinoma.

EGFR-Tyrosine Kinase Inhibitors Induced Activation of the Autocrine CXCL10/CXCR3 Pathway through Crosstalk between the Tumor and the Microenvironment in EGFR-Mutant Lung Cancer

CXCL10 is a cytokine that is elevated during EGFR-TKI treatment in the tumor microenvironment of lung cancer. Here, we report an original study that the impact of the CXCL10/CXCR3 pathway on EGFR-TKI resistance in EGFR-mutant lung cancer through a cytokine array analysis during in vitro coculture with tumor cells and activated PBMCs treated with EGFR-TKI, as well as the serial analysis of CXCL10 in EGFR-mutant lung cancer transgenic mice during EGFR-TKI treatment. In EGFR-mutant tumor cells cocultured with activated PBMCs, EGFR-TKI treatment increased CXCL10 in the supernatant; this activated CXCR3 in the tumor cells to induce the phosphorylation of Src and the NF-κB subunit, p65, and the expression of HIF-1α. CXCL10 siRNA treatment of EGFR-mutant tumor cells also decreased CXCL10 in the supernatant from coculturing with activated PBMCs, suggesting that the effects of CXCL10 occur via autocrine and paracrine pathways. Importantly, elevated CXCL10/CXCR3 signaling was recapitulated in a transgenic lung cancer mouse model. Our results show that increased CXCL10 levels during early EGFR-TKI treatment stimulate oncogenic signaling of persistent tumor cells to contribute to EGFR-TKI resistance via autocrine and paracrine pathways.

Identification of hub genes correlated with tumor-associated M1-like macrophage infiltration in soft tissue sarcomas

Soft tissue sarcomas (STS) are a heterogeneous series of tumors that might result in severe disability and death. Tumor-associated M1-like macrophage infiltration plays a critical role in tumor development and progression. This study aimed at identifying the hub genes associated with M1-like macrophage infiltration in STS cells. First, the expression profiles from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were imported to calculate the level of M1-like macrophage infiltration by CIBERSORTx. Afterward, the Kaplan-Meier survival analysis was performed to evaluate the correlation between macrophage infiltration and prognosis. Then, weighted gene co-expression network analysis (WGCNA) and protein-protein interaction analysis of GEO data were applied to identify the key gene related to M1-like macrophage infiltration, followed by the functional analysis using TCGA cohort to validate downstream signaling associated with the gene. Finally, pan-cancer analysis was conducted to investigate the gene function in other types of tumors. We found LCK expression positively related to the M1-like macrophage infiltration level, and it positively regulated the expression level of genes regulated to macrophage polarization, and chemotaxis, including interferon-γ (INF-γ), interleukin-12 (IL12), tumor necrosis factor (TNF), PI3K, NF-κB, and CXCL9, 10, and 11. In summary, an 'LCK-INF-γ/IL-12-TNF/PI3K-NF-κB' axis might exist in STS cells that regulate M1-like macrophage infiltration.

Proteomic Profiling of Extracellular Vesicles Released by Leptin-Treated Breast Cancer Cells: A Potential Role in Cancer Metabolism

Tumor extracellular vesicles (EVs), as endocytic vesicles able to transport nucleic acids, proteins, and metabolites in recipient cells, have been recognized fundamental mediators of cell-to-cell communication in breast cancer. The biogenesis and release of EVs are highly regulated processes and both the quantity of EVs and their molecular cargo might reflect the metabolic state of the producing cells. We recently demonstrated that the adipokine leptin, whose circulating levels correlate with adipose tissue expansion, is an inducer of EV release from breast cancer cells. Here, we show a specific proteomic signature of EVs released by MCF-7 breast cancer cells grown in the presence of leptin (Lep-EVs), in attempt to find additional molecular effectors linking obesity to breast cancer biology. An analysis of the proteomic profile of Lep-EVs by LC-MS/MS revealed a significant enrichment in biological processes, molecular functions, and cellular components mainly related to mitochondrial machineries and activity, compared to protein content of EVs from untreated breast cancer cells. Metabolic investigations, carried out to assess the autocrine effects of these vesicles on breast cancer cells, revealed that Lep-EVs were able to increase ATP levels in breast cancer cells. This result is associated with increased mitochondrial respiration evaluated by Seahorse analyzer, supporting the concept that Lep-EVs can modulate MCF-7 breast cancer cell oxidative metabolism. Moreover, taking into account the relevance of tumor immune cell crosstalk in the tumor microenvironment (TME), we analyzed the impact of these vesicles on macrophage polarization, the most abundant immune component in the breast TME. We found that tumor-derived Lep-EVs sustain the polarization of M0 macrophages, derived from the human THP-1 monocytic cells, into M2-like tumor-associated macrophages, in terms of metabolic features, phagocytic activity, and increased expression of CD206-positive population. Overall, our results indicate that leptin by inducing the release of EV-enriched in mitochondrial proteins may control the metabolism of MCF-7 breast cancer cells as well as that of macrophages. Characterization of tumor-derived EV protein cargo in an obesity-associated milieu, such as in the presence of elevated leptin levels, might allow identifying unique features and specific metabolic mechanisms useful to develop novel therapeutic approaches for treatment of breast cancer, especially in obese patients.

A CAF-Fueled TIMP-1/CD63/ITGB1/STAT3 Feedback Loop Promotes Migration and Growth of Breast Cancer Cells

Simple Summary

Carcinoma-associated fibroblasts (CAFs) are a major cellular component of the tumor microenvironment and influence cancer cell behavior in numerous ways. A large part of their actions is based on their high secretory activity, leading to the exposure of cancer cells to all kinds of bioactive factors, such as interleukin-6 (IL-6). Here, we present data showing that CAF-derived TIMP-1 activates STAT3 in breast cancer cells in cooperation with CD63 and integrin β1. In turn, STAT3 increases TIMP-1 secretion by breast cancer cells, leading to a TIMP-1/CD63/integrin β1/STAT3 positive feedback loop, which can be further fueled by IL-6. Functionally, this feedback loop is important for the CAF-induced increase in migratory activity and for CAF-induced resistance to the anti-estrogen fulvestrant.

Abstract

TIMP-1 is one of the many factors that CAFs have been shown to secret. TIMP-1 can act in a tumor-supportive or tumor-suppressive manner. The purpose of this study was to elucidate the role of CAF-secreted TIMP-1 for the effects of CAFs on breast cancer cell behavior. Breast cancer cells were exposed to conditioned medium collected from TIMP-1-secreting CAFs (CAF-CM), and the specific effects of TIMP-1 on protein expression, migration and growth were examined using TIMP-1-specifc siRNA (siTIMP1), recombinant TIMP-1 protein (rhTIMP-1) and TIMP-1 level-rising phorbol ester. We observed that TIMP-1 increased the expression of its binding partner CD63 and induced STAT3 and ERK1/2 activation by cooperating with CD63 and integrin β1. Since TIMP-1 expression was found to be dependent on STAT3, TIMP-1 activated its own expression, resulting in a TIMP-1/CD63/integrin β1/STAT3 feedback loop. IL-6, a classical STAT3 activator, further fueled this loop. Knock-down of each component of the feedback loop prevented the CAF-induced increase in migratory activity and inhibited cellular growth in adherent cultures in the presence and absence of the anti-estrogen fulvestrant. These data show that TIMP-1/CD63/integrin β1/STAT3 plays a role in the effects of CAFs on breast cancer cell behavior.

Natural cell based biomimetic cellular transformers for targeted therapy of digestive system cancer

Digestive system cancer is the most common cause of cancer death in the world. Although cancer treatment options are increasingly diversified, the mortality rate of malignant cancer of the digestive system remains high. Therefore, it is necessary to explore effective cancer treatment methods. Recently, biomimetic nanoparticle delivery systems based on natural cells that organically integrate the low immunogenicity, high biocompatibility, cancer targeting, and controllable, versatile functionality of smart nanocarrier design with natural cells have been expected to break through the bottleneck of tumor targeted therapy. In this review, we focus on the dynamic changes and complex cellular communications that occur in vivo in natural cells based vehicles. Recent studies on the development of advanced targeted drug delivery systems using the dynamic behaviors such as specific surface protein affinity, morphological changes, and phenotypic polarization of natural cells are summarized. In addition to drug delivery mediated by dynamic behavior, functional “delivery” based on the natural cell themselves is also involved. Aiming to make the best use of the functions of cells, providing clues for the development of advanced drug delivery platforms.

Crosstalk between tumor-associated macrophages and tumor cells promotes chemoresistance via CXCL5/PI3K/AKT/mTOR pathway in gastric cancer

BACKGROUND

5-fluorouracil (5-FU)-based chemotherapy regimen has been widely used for the treatment of gastric cancer, but meanwhile the development of chemotherapeutic resistance remains a major clinical challenge. Tumor microenvironment (TME) frequently correlates with the development of chemoresistance in human cancer. As a major component of TME, the role of tumor-associated macrophages (TAMs) in the chemoresistance of gastric cancer has not been fully elucidated.

METHODS

Immunohistochemistry (IHC) was applied to detect the density of TAMs in clinical samples of 103 patients with gastric cancer who had undergone 5-FU-based neoadjuvant chemotherapy. 5-FU-resistant gastric cell lines MKN45-R and HGC27-R were established, macrophages were then separately co-cultured with MKN45-R, HGC27-R cells and their parental cells. The effect of gastric cancer cells on the polarization of macrophages, the biological function of M2-polaried macrophages and the mechanism for promoting 5-FU-resistance were investigated. Then the correlation between the expression of CXC motif chemokine ligand 5 (CXCL5) and the infiltration of hemoglobin scavenger receptor (CD163) positive and mannose receptor (CD206) positive macrophages was analyzed, the prognostic value of CXCL5 expression in clinical samples was further explored.

RESULTS

The high infiltration of macrophages marked by CD68 in gastric cancer samples was significantly associated with the resistance of gastric cancer to chemotherapy. Gastric cancer cells could modulate macrophages to M2-like polarization through indirect co-culture, and chemoresistant cells were more efficient in inducing macrophages polarization to M2 phenotype. Co-culturing M2-polarized macrophages in turn enhanced 5-FU-resistance of gastric cancer cells, and it was further verified that CXCL5 derived from M2-polarized macrophages promoted chemoresistance through activing the PI3K/AKT/mTOR pathway. Besides, high level of CXCL5 could recruit monocytes to form more M2-polarized macrophages. Clinically, high expression of CXCL5 in gastric cancer samples was associated with the high infiltration of CD163 positive macrophages and CD206 positive macrophages, and patients with high expression of CXCL5 presented lower overall survival (OS) rates than those with low expression of CXCL5.

CONCLUSION

Interaction between TAMs and gastric cancer cells promoted chemoresistance in gastric cancer via CXCL5/PI3K/AKT/mTOR pathway. Thus, targeting TAMs and blocking the cell-cell crosstalk between TAMs and gastric cancer cells may represent prospective therapeutic strategies for patients with gastric cancer.

Comprehensive analyses of a tumor-infiltrating lymphocytes-related gene signature regarding the prognosis and immunologic features for immunotherapy in bladder cancer on the basis of WGCNA

Tumor-infiltrating lymphocyte (TIL) is a class of cells with important immune functions and plays a crucial role in bladder cancer (BCa). Several studies have shown the clinical significance of TIL in predicting the prognosis and immunotherapy efficacy. TIL-related gene module was screened utilizing weighted gene coexpression network analysis. We screened eight TIL-related genes utilizing univariate Cox regression analysis, least absolute shrinkage and selection operator (LASSO) Cox regression analysis, and multivariate Cox regression analysis. Then, we established a TIL-related signature model containing the eight selected genes and subsequently classified all patients into two groups, that is, the high-risk as well as low-risk groups. Gene mutation status, prognosis, immune cell infiltration, immune subtypes, TME, clinical features, and immunotherapy response were assessed among different risk subgroups. The results affirmed that the TIL-related signature model was a reliable predictor of overall survival (OS) for BCa and was determined as an independent risk factor for BCa patients in two cohorts. Moreover, the risk score was substantially linked to age, tumor staging, TNM stage, and pathological grade. And there were different mutational profiles, biological pathways, immune scores, stromal scores, and immune cell infiltration in the tumor microenvironment (TME) between the two risk groups. In particular, immune checkpoint genes’ expression was remarkably different between the two risk groups, with patients belonging to the low-risk group responding better to immune checkpoint inhibition (ICI) therapy. In conclusion, our study demonstrates that the TIL-related model was a reliable signature in anticipating prognosis, immune status, and immunotherapy response, which can help in screening patients who respond to immunotherapy.

Novel macrophage-related gene prognostic index for glioblastoma associated with M2 macrophages and T cell dysfunction

This study aims to construct a Macrophage-Related Gene Prognostic Index (MRGPI) for glioblastoma (GBM) and explore the underlying molecular, metabolic, and immunological features. Based on the GBM dataset from The Cancer Genome Atlas (n = 156), 13 macrophage-related hub genes were identified by weighted gene co-expression network (WGCNA) analysis. 5 prognostic genes screened by Kaplan-Meire (K-M) analysis and Cox regression model were used to construct the MRGPI, including GPR84, NCF2, HK3, LILRB2, and CCL18. Multivariate Cox regression analysis found that the MRGPI was an independent risk factor (HR = 2.81, CI95: 1.13-6.98, p = 0.026), leading to an unfavorable outcome for the MRGPI-high group, which was further validated by 4 validation GBM cohorts (n = 728). Thereafter, the molecular, metabolic, and immune features and the clinical implications of the MRGPI-based groups were comprehensively characterized. Gene set enrichment analysis (GSEA) found that immune-related pathways, including inflammatory and adaptive immune response, and activated eicosanoid metabolic pathways were enriched in the MRGPI-high group. Besides, genes constituting the MRGPI was primarily expressed by monocytes and macrophages at single-cell scope and was associated with the alternative activation of macrophages. Moreover, correlation analysis and receiver operating characteristic (ROC) curves revealed the relevance between the MRGPI with the expression of immune checkpoints and T cell dysfunction. Thus, the responsiveness of samples in the MRGPI-high group to immune checkpoint inhibitors (ICI) was detected by algorithms, including Tumor Immune Dysfunction and Exclusion (TIDE) and Submap. In contrast, the MRGPI-low group had favorable outcome, was less immune active and insensitive to ICI. Together, we have developed a promising biomarker to classify the prognosis, metabolic and immune features for GBM, and provide references for facilitating the personalized application of ICI in GBM.

The Roles of Tumor-Associated Macrophages in Prostate Cancer

The morbidity of prostate cancer (PCa) is rising year by year, and it has become the primary cause of tumor-related mortality in males. It is widely accepted that macrophages account for 50% of the tumor mass in solid tumors and have emerged as a crucial participator in multiple stages of PCa, with the huge potential for further treatment. Oftentimes, tumor-associated macrophages (TAMs) in the tumor microenvironment (TME) behave like M2-like phenotypes that modulate malignant hallmarks of tumor lesions, ranging from tumorigenesis to metastasis. Several clinical studies indicated that mean TAM density was higher in human PCa cores versus benign prostatic hyperplasia (BPH), and increased biopsy TAM density potentially predicts worse clinicopathological characteristics as well. Therefore, TAM represents a promising target for therapeutic intervention either alone or in combination with other strategies to halt the “vicious cycle,” thus improving oncological outcomes. Herein, we mainly focus on the fundamental aspects of TAMs in prostate adenocarcinoma, while reviewing the mechanisms responsible for macrophage recruitment and polarization, which has clinical translational implications for the exploitation of potentially effective therapies against TAMs.

Pan-cancer analysis of the prognosis and immunological role of AKAP12: A potential biomarker for resistance to anti-VEGF inhibitors

The primary or acquired resistance to anti-VEGF inhibitors remains a common problem in cancer treatment. Therefore, identifying potential biomarkers enables a better understanding of the precise mechanism. Through the GEO database, three profiles associated with bevacizumab (BV) resistance to ovarian cancer, glioma, and non-small-cell lung carcinoma, respectively, were collected for the screening process, and two genes were found. A-kinase anchor protein 12 (AKAP12), one of these two genes, correlates with tumorigenesis of some cancers. However, the role of AKAP12 in pan-cancer remains poorly defined. The present study first systematically analyzed the association of AKAP12 with anti-VEGF inhibitors’ sensitivity, clinical prognosis, DNA methylation, protein phosphorylation, and immune cell infiltration across various cancers via bioinformatic tools. We found that AKAP12 was upregulated in anti-VEGF therapy-resistant cancers, including ovarian cancer (OV), glioblastoma (GBM), lung cancer, and colorectal cancer (CRC). A high AKAP12 expression revealed dismal prognoses in OV, GBM, and CRC patients receiving anti-VEGF inhibitors. Moreover, AKAP12 expression was negatively correlated with cancer sensitivity towards anti-VEGF therapy. Clinical prognosis analysis showed that AKAP12 expression predicted worse prognoses of various cancer types encompassing colon adenocarcinoma (COAD), OV, GBM, and lung squamous cell carcinoma (LUSC). Gene mutation status may be a critical cause for the involvement of AKAP12 in resistance. Furthermore, lower expression of AKAP12 was detected in nearly all cancer types, and hypermethylation may explain its decreased expression. A decreased phosphorylation of T1760 was observed in breast cancer, clear-cell renal cell carcinoma, and lung adenocarcinoma. For the immunologic significance, AKAP12 was positively related to the abundance of pro-tumor cancer-associated fibroblasts (CAFs) in various types of cancer. The results of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis suggested that “cell junction organization” and “MAPK pathway” participated in the effect of AKAP12. Importantly, we discovered that AKAP12 expression was greatly associated with metastasis of lung adenocarcinoma as well as differential and angiogenesis of retinoblastoma through investigating the single-cell sequencing data. Our study showed that the dual role of AKAP12 in various cancers and AKAP12 could serve as a biomarker of anti-VEGF resistance in OV, GBM, LUSC, and COAD.

A composite score based on immune-related gene prognostic index and m6A risk score of head and neck squamous cell carcinoma.. [DOI: 10.21203/rs.3.rs-1987322/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background:Immunotherapy has been demonstrated favorable in head and neck squamous cell carcinoma (HNSCC). Studies indicated that immune-related gene prognostic index (IRGPI) was a robust signature, and N6-methyladenosine (m6A) methylation had a significant impact on the tumor immune microenvironment (TIME) and immunotherapy of HNSCC. Thus, combining IRGPI with m6A status should offer a better predictive power for immune responses.Methods:HNSCC samples from The Cancer Genome Atlas (TCGA, n=498) and Gene Expression Omnibus database (GSE65858, n = 270) were used in this study. Cox regression analysis was used to construct the IRGPI through immune-related hub genes which were identified by weighted gene co-expression network analysis (WGCNA). The m6A risk score was constructed by least absolute shrinkage and selection operator regression analysis. Principal component analysis was used to construct a composite score, and systematically correlate subgroups according to TIME cell-infiltrating characteristics.Results:A composite score was determined based on IRGPI and m6A risk score. HNSCC patients in the TCGA were divided into four subgroups：A (IRGPI-High&m6A-risk-High, n=127), B (IRGPI-High&m6A-risk-Low, n=99), C (IRGPI-Low&m6A-risk-High, n=99) and D (IRGPI-Low&m6A-risk-Low, n=128), and overall survival (OS) was significantly different between subgroups (P< 0.001). The characteristics of TIME cell infiltration in the four subgroups were significantly different in subgroups (P< 0.05). The ROC curves show the predictive value of composite score for OS was superior to any other scores.Conclusions:The composite score is a promising prognostic signature which might distinguish immune and molecular characteristics, predict prognosis, and guide more effective immunotherapeutic strategies for HNSCC.

PD-1/L1 inhibitor plus chemotherapy in the treatment of sarcomas

There is an urgent clinical need for new therapeutic regimens for the effective treatment of advanced sarcomas. Accumulating evidence suggests that programmed death receptor-1/programmed death protein ligand-1 (PD-1/L1) inhibitors have synergistic effects with chemotherapy and have been approved for treatment of lung cancer, gastroesophageal cancer, and breast cancer. In this review, we reviewed the synergistic mechanism of PD-1/L1 inhibitors plus chemotherapy in the treatment of cancers, and the application of this combined regimen in several cancers, followed by a summary of the current evidence on the application of this combined regimen in the treatment of sarcomas as well as the main clinical trials currently underway. Based on the findings of this review, we believe that this combined approach will play an important role in the treatment of some subtypes of sarcomas in the future.

Checkpoint molecules on infiltrating immune cells in colorectal tumor microenvironment

Colorectal cancer (CRC) is one of the most prevalent cancer types worldwide, with a high mortality rate due to metastasis. The tumor microenvironment (TME) contains multiple interactions between the tumor and the host, thus determining CRC initiation and progression. Various immune cells exist within the TME, such as tumor-infiltrating lymphocytes (TILs), tumor-associated macrophages (TAMs), and tumor-associated neutrophils (TANs). The immunotherapy approach provides novel opportunities to treat solid tumors, especially toward immune checkpoints. Despite the advances in the immunotherapy of CRC, there are still obstacles to successful treatment. In this review, we highlighted the role of these immune cells in CRC, with a particular emphasis on immune checkpoint molecules involved in CRC pathogenesis.

Combination of dl922-947 Oncolytic Adenovirus and G-Quadruplex Binders Uncovers Improved Antitumor Activity in Breast Cancer

G-quadruplexes (G4s) are nucleic secondary structures characterized by G-tetrads. G4 motif stabilization induces DNA damage and cancer cell death; therefore, G4-targeting small molecules are the focus of clinical investigation. DNA destabilization induced by G4 ligands might potentiate the anticancer activity of agents targeting DNA or inhibiting its repair such as oncolytic viruses. This study represents the first approach combining G4 ligands, BRACO-19 (B19), pyridostatin (PDS), and the adenovirus dl922-947 in breast cancer cells. We demonstrated that G4 binders and dl922-947 induce cytotoxicity in breast cancer cells (MDA-MB-231 and MCF-7) and at higher doses in other neoplastic cell lines of thyroid (BHT-101 cells) and prostate (PC3 cells). G4 binders induce G4 motifs distributed in the S and G2/M phases in MCF-7 cells. G4 binder/dl922-947 combination increases cell cytotoxicity and the accumulation in subG0/G1. Indeed, G4 binders favor viral entry and replication with no effect on coxsackie and adenovirus receptor. Notably, dl922-947 induces G4 motifs and its combination with PDS potentiates this effect in MCF-7 cells. The agents alone or in combination similarly enhanced cell senescence. Additionally, PDS/dl922-947 combination inactivates STING signaling in MDA-MB-231 cells. Our results suggest that G4 binder/virotherapy combination may represent a novel therapeutic anticancer approach.

Local and systemic inflammation triggers different outcomes of tumor growth related to infiltration of anti-tumor or pro-tumor macrophages

BACKGROUND

Previous evidence suggests inflammation may be a double-edged sword with cancer-promoting and cancer suppressing function. In this study, we explore the impact of local and systemic inflammation on cancer growth.

METHODS

Female BALB/C mice were subcutaneously implanted with foreign body (plastic plates) to build up a local inflammation and intraperitoneally injected with PolyIC or lipopolysaccharides (LPS) to build up a systemic inflammation, followed by subcutaneous injection of 5  × 10 5 colon cancer cells. Immunohistochemistry and enzyme linked immunosorbent assay were utilized to detect the Ki67 and interleukin (IL) 6, IL-1β, and monocyte chemoattractant protein-1 expression in the tumor tissues and serum, respectively. The distributions of immune cells and expression of toll-like receptors (TLRs) were evaluated by flow cytometry (FCM) and quantitative real time-polymerase chain reaction.

RESULTS

The results showed that local inflammation induced by foreign body implantation suppressed tumor growth with decreased tumor weight ( P   =  0.001), volume ( P   =  0.004) and Ki67 index ( P   <  0.001). Compared with the control group, myeloid-derived suppressive cells sharply decreased ( P   =  0.040), while CD4 + T cells slightly increased in the tumor tissues of the group of foreign body-induced local inflammation ( P   =  0.035). Moreover, the number of M1 macrophages ( P   =  0.040) and expression of TLRs, especially TLR3 ( P  < 0.001) and TLR4 ( P  < 0.001), were significantly up-regulated in the foreign body group. Contrarily, tumor growth was significantly promoted in LPS or PolyIC-induced systemic inflammation ( P   =  0.009 and 0.006). FCM results showed M1 type macrophages ( P   =  0.017 and 0.006) and CD8 + T cells ( P   =  0.031 and 0.023) were decreased, while M2 type macrophages ( P  = 0.002 and 0.007) were significantly increased in tumor microenvironment of LPS or PolyIC-induced systemic inflammation group. In addition, the decreased expression of TLRs was detected in LPS or PolyIC group.

CONCLUSIONS

The foreign body-induced local inflammation inhibited tumor growth, while LPS or PolyIC- induced systemic inflammation promoted tumor growth. The results suggested that the different outcomes of tumor growth might be attributed to the infiltration of anti-tumor or pro-tumor immune cells, especially M1 or M2 type macrophages into tumor microenvironment.

Reactive Oxygen Species Bridge the Gap between Chronic Inflammation and Tumor Development

According to numerous animal studies, adverse environmental stimuli, including physical, chemical, and biological factors, can cause low-grade chronic inflammation and subsequent tumor development. Human epidemiological evidence has confirmed the close relationship between chronic inflammation and tumorigenesis. However, the mechanisms driving the development of persistent inflammation toward tumorigenesis remain unclear. In this study, we assess the potential role of reactive oxygen species (ROS) and associated mechanisms in modulating inflammation-induced tumorigenesis. Recent reports have emphasized the cross-talk between oxidative stress and inflammation in many pathological processes. Exposure to carcinogenic environmental hazards may lead to oxidative damage, which further stimulates the infiltration of various types of inflammatory cells. In turn, increased cytokine and chemokine release from inflammatory cells promotes ROS production in chronic lesions, even in the absence of hazardous stimuli. Moreover, ROS not only cause DNA damage but also participate in cell proliferation, differentiation, and apoptosis by modulating several transcription factors and signaling pathways. We summarize how changes in the redox state can trigger the development of chronic inflammatory lesions into tumors. Generally, cancer cells require an appropriate inflammatory microenvironment to support their growth, spread, and metastasis, and ROS may provide the necessary catalyst for inflammation-driven cancer. In conclusion, ROS bridge the gap between chronic inflammation and tumor development; therefore, targeting ROS and inflammation represents a new avenue for the prevention and treatment of cancer.

Clinical significance of signal regulatory protein alpha and T cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif domain expression in undifferentiated pleomorphic sarcoma

PURPOSE

Undifferentiated pleomorphic sarcoma (UPS) is associated with poor prognosis. Recently, signal regulatory protein alpha (SIRPα), which is the immune checkpoint of macrophages, and T cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif domains (TIGIT), which is the immune checkpoint of T cells and natural killer cells, have been considered as potential targets for cancer immunotherapy. This study aimed to assess the value of SIRPα and TIGIT as prognostic factors of UPS.

MATERIALS AND METHODS

The cBio Cancer Genomics Portal was used to analyze mRNA expression data of 50 UPS cases in the Cancer Genome Atlas. We retrieved 49 UPS cases and performed immunohistochemistry (IHC) to detect programmed death ligand 1 (PD-L1), SIRPα, CD68, CD163, TIGIT, CD155, and CD8.

RESULTS

SIRPα was positively associated with CD163 (Pearson's r = 0.51, p = 0.0002) as per open access data and IHC of the cohort (p = 0.002), which revealed that SIRPα-positive macrophage infiltration was higher in UPS cells with ≥ 1% PD-L1 expression than that in UPS cells with < 1% PD-L1 expression (p = 0.047). TIGIT was positively correlated with PD-L1 (r = 0.54, p < 0.0001) and CD8A (r = 0.98, p < 0.0001). In 35 of 49 cases, IHC revealed high levels of TIGIT expression on tumor cells. Furthermore, TIGIT expression on tumor cells was negatively correlated with CD155-positive (p = 0.0144) and CD8-positive (p = 0.0487) cell infiltration. Survival analysis showed that the high degree of SIRPα-positive macrophage infiltration was associated with poor overall survival and metastasis (p < 0.0001, p = 0.0006, respectively).

CONCLUSION

SIRPα-positive macrophages infiltrated UPS cells, which predicted poor prognosis. High TIGIT expression on tumor cells was associated with decreased levels of tumor-infiltrating macrophages in UPS.

Tumour Stem Cells in Breast Cancer

Tumour stem cells (CSCs) are a self-renewing population that plays important roles in tumour initiation, recurrence, and metastasis. Although the medical literature is extensive, problems with CSC identification and cancer therapy remain. This review provides the main mechanisms of CSC action in breast cancer (BC): CSC markers and signalling pathways, heterogeneity, plasticity, and ecological behaviour. The dynamic heterogeneity of CSCs and the dynamic transitions of CSC⁻ non-CSCs and their significance for metastasis are considered.

Dual Aptamers Engineering M1 Macrophage with Enhanced Specific Targeting and Checkpoint Blocking for Solid Tumor Immunotherapy

Chimeric antigen receptor T cells (CAR-T) therapy has faced a series of challenges and shown very little efficacy in solid tumors to date. Although genetically engineered macrophages have achieved the definite therapeutic effect in solid tumors, heterogeneous expression of engineered proteins and potential for toxicity limit further applications. Herein, we proposed a nongenetic and simple macrophage cell engineering strategy through glycan metabolic labeling and click reaction for treatment of solid tumors. The aptamers-engineered M1 macrophage (ApEn-M1) showed enhanced active targeting ability for tumor cells in vitro and in vivo, resulting in significantly cytotoxicity effect. Moreover, ApEn-M1 exhibited superior antitumor efficacy in breast cancer xenograft mouse model and lung metastasis mouse model of breast cancer. Interestingly, the ApEn-M1 could reprogram the immunity microenvironment by increasing the T cells infiltration and enhancing T cells activity in tumor region. Additionally, the administration of ApEn-M1 showed no obvious systemic side effects. With glycan metabolic labeling, the macrophages could be efficiently labeled with aptamers on the cell surface via click reaction without genetic alteration or cell damage. Hence, this study serves as a proof of concept for cell-surface anchor-engineering and expands the range of nongenetic macrophage cell engineering strategies.

Tumor-associated macrophage-derived exosomes transmitting miR-193a-5p promote the progression of renal cell carcinoma via TIMP2-dependent vasculogenic mimicry

Previous studies have investigated whether tumor-associated macrophages (TAMs) play tumorigenic and immunosuppressive roles to encourage cancer development, but the role of TAMs in regulating vasculogenic mimicry (VM) in clear-cell renal cell carcinoma (ccRCC) cells has not been completely clarified. We conducted immunostaining of the tumor-associated macrophage biomarkers CD68/CD163 and double staining for PAS/CD31 in ccRCC human specimens to find that higher TAM infiltration was positively correlated with VM formation. Then we demonstrated that TAM-derived exosomes downregulate TIMP2 expression in RCC cells to promote VM and invasion by shuttling miR-193a-5p. Mechanistic analysis indicated that HIF-1α upregulation in macrophages could transcriptionally increase miR-193a-5p expression. Exosome-shuttled miR-193a-5p then targeted the 3′ untranslated region (UTR) of TIMP2 mRNA to suppress its translation. A preclinical study using an in vivo orthotopic xenograft model of ccRCC in mice substantiated that TAM-derived exosomes enhance VM and enable tumor progression, which confirmed our in vitro data. Suppressing TAM-derived exosomal miR-193a-5p successfully inhibited tumor progression and metastasis. Overall, miR-193a-5p from TAM-derived exosomes downregulates the TIMP2 gene to facilitate the development of RCC, which provides a novel perspective for developing therapeutic strategies for RCC.

Structural Requirements for the Binding of a Peptide to Prohibitins on the Cell Surface of Monocytes/Macrophages

The screening of phage peptide libraries resulted in the identification of a sequence (named NW peptide, NWYLPWLGTNDW) that specifically binds to human monocytes and macrophages. Although the NW peptide can be used for the targeted delivery of therapeutics without knowledge of its receptor(s), the identification of-its binding partners will support future clinical applications-Here, we used the biotinylated NW peptide for cross-linking cell surface receptor(s) on live cells or as bait in pull-down assays with membrane proteins isolated from monocytes or human THP-1 cells differentiated into macrophages. Proteomic analysis of the captured proteins identified cell surface prohibitins (PHB1 and PHB2) and modified albumin as binding partners. Using flow cytometry and pull-down methods, we demonstrated that PHB1 and PHB2 interact directly with the NW peptide. Confocal imaging showed co-localization of the peptide with PHB1 on the surface of monocytes. Single replacement of either tryptophan or leucine with alanine completely inhibited binding, whereas the replacement of asparagine at position 1 or 10 and aspartic acid at position 11 with alanine did not affect the binding of the peptide variants. Neutral amino acid replacement of tryptophan at positions 2, 6, and 12 with tyrosine or phenylalanine also abolished the binding, implying that the indole ring of tryptophan is indispensable for the NW peptide to bind. Overall, the data suggest that membrane-associated prohibitins might be a useful target for the delivery of therapeutics to monocytes/macrophages and that tryptophan and leucine are key residues for peptide binding.