Tumor microenvironment remodeling via targeted depletion of M2-like tumor-associated macrophages for cancer immunotherapy

Boosting Checkpoint Immunotherapy with Biomimetic Nanodrug Delivery Systems

Immune checkpoint blockade (ICB) has achieved unprecedented progress in tumor immunotherapy by blocking specific immune checkpoint molecules. However, the high biodistribution of the drug prevents it from specifically targeting tumor tissues, leading to immune-related adverse events. Biomimetic nanodrug delivery systems (BNDSs) readily applicable to ICB therapy have been widely developed at the preclinical stage to avoid immune-related adverse events. By exploiting or mimicking complex biological structures, the constructed BNDS as a novel drug delivery system has good biocompatibility and certain tumor-targeting properties. Herein, the latest findings regarding the aforementioned therapies associated with ICB therapy are highlighted. Simultaneously, prospective bioinspired engineering strategies can be designed to overcome the four-level barriers to drug entry into lesion sites. In future clinical translation, BNDS-based ICB combination therapy represents a promising avenue for cancer treatment.

Ultrasound-augmented cancer immunotherapy

Cancer is a growing worldwide health problem with the most broadly studied treatments, in which immunotherapy has made notable advancements in recent years. However, innumerable patients have presented a poor response to immunotherapy and simultaneously experienced immune-related adverse events, with failed therapeutic results and increased mortality rates. Consequently, it is crucial to develop alternate tactics to boost therapeutic effects without producing negative side effects. Ultrasound is considered to possess significant therapeutic potential in the antitumor field because of its inherent characteristics, including cavitation, pyrolysis, and sonoporation. Herein, this timely review presents the comprehensive and systematic research progress of ultrasound-enhanced cancer immunotherapy, focusing on the various ultrasound-related mechanisms and strategies. Moreover, this review summarizes the design and application of current sonosensitizers based on sonodynamic therapy, with an attempt to provide guidance on new directions for future cancer therapy.

Role of Tumor-Associated Macrophages in Cervical Cancer: Integrating Classical Perspectives with Recent Technological Advances

Tumor-associated macrophages (TAMs) play a pivotal role in the tumor microenvironment, influencing cancer progression and contributing to poor prognosis. However, in cervical cancer (CC), their significance and involvement are relatively less studied than in other gynecological cancers such as ovarian and endometrial cancer. This review aims to provide an overview of TAMs, covering their origins and phenotypes and their impact on CC progression, along with major TAM-targeted therapeutic approaches. Furthermore, we advocate for the integration of cutting-edge research methodologies, such as single-cell RNA sequencing and spatial RNA sequencing, to enable in-depth and comprehensive investigations into TAMs in CC, which would be beneficial in leading to more personalized and effective immunotherapy strategies for patients with CC.

Nanomaterials-Involved Tumor-Associated Macrophages' Reprogramming for Antitumor Therapy

Tumor-associated macrophages (TAMs) play pivotal roles in tumor development. As primary contents of tumor environment (TME), TAMs secrete inflammation-related substances to regulate tumoral occurrence and development. There are two kinds of TAMs: the tumoricidal M1-like TAMs and protumoral M2-like TAMs. Reprogramming TAMs from immunosuppressive M2 to immunocompetent M1 phenotype is considered a feasible way to improve immunotherapeutic efficiency. Notably, nanomaterials show great potential for biomedical fields due to their controllable structures and properties. There are many types of nanomaterials that exhibit great regulatory activities for TAMs' reprogramming. In this review, the recent progress of nanomaterials-involved TAMs' reprogramming is comprehensively discussed. The various nanomaterials for TAMs' reprogramming and the reprogramming strategies are summarized and introduced. Additionally, the challenges and perspectives of TAMs' reprogramming for efficient therapy are discussed, aiming to provide inspiration for TAMs' regulator design and promote the development of TAMs-mediated immunotherapy.

Nanomaterials augmented bioeffects of ultrasound in cancer immunotherapy

Immunotherapy as a milestone in cancer treatment has made great strides in the past decade, but it is still limited by low immune response rates and immune-related adverse events. Utilizing bioeffects of ultrasound to enhance tumor immunotherapy has attracted more and more attention, including sonothermal, sonomechanical, sonodynamic and sonopiezoelectric immunotherapy. Moreover, the emergence of nanomaterials has further improved the efficacy of ultrasound mediated immunotherapy. However, most of the summaries in this field are about a single aspect of the biological effects of ultrasound, which is not comprehensive and complete currently. This review proposes the recent progress of nanomaterials augmented bioeffects of ultrasound in cancer immunotherapy. The concept of immunotherapy and the application of bioeffects of ultrasound in cancer immunotherapy are initially introduced. Then, according to different bioeffects of ultrasound, the representative paradigms of nanomaterial augmented sono-immunotherapy are described, and their mechanisms are discussed. Finally, the challenges and application prospects of nanomaterial augmented ultrasound mediated cancer immunotherapy are discussed in depth, hoping to pave the way for cancer immunotherapy and promote the clinical translation of ultrasound mediated cancer immunotherapy through the reasonable combination of nanomaterials augmented ultrasonic bioeffects.

Strategies to Reverse Hypoxic Tumor Microenvironment for Enhanced Sonodynamic Therapy

Sonodynamic therapy (SDT) has emerged as a highly effective modality for the treatment of malignant tumors owing to its powerful penetration ability, noninvasiveness, site-confined irradiation, and excellent therapeutic efficacy. However, the traditional SDT, which relies on oxygen availability, often fails to generate a satisfactory level of reactive oxygen species because of the widespread issue of hypoxia in the tumor microenvironment of solid tumors. To address this challenge, various approaches are developed to alleviate hypoxia and improve the efficiency of SDT. These strategies aim to either increase oxygen supply or prevent hypoxia exacerbation, thereby enhancing the effectiveness of SDT. In view of this, the current review provides an overview of these strategies and their underlying principles, focusing on the circulation of oxygen from consumption to external supply. The detailed research examples conducted using these strategies in combination with SDT are also discussed. Additionally, this review highlights the future prospects and challenges of the hypoxia-alleviated SDT, along with the key considerations for future clinical applications. These considerations include the development of efficient oxygen delivery systems, the accurate methods for hypoxia detection, and the exploration of combination therapies to optimize SDT outcomes.

Comparative Insight into Microglia/Macrophages-Associated Pathways in Glioblastoma and Alzheimer's Disease

Microglia and macrophages are pivotal to the brain's innate immune response and have garnered considerable attention in the context of glioblastoma (GBM) and Alzheimer's disease (AD) research. This review delineates the complex roles of these cells within the neuropathological landscape, focusing on a range of signaling pathways-namely, NF-κB, microRNAs (miRNAs), and TREM2-that regulate the behavior of tumor-associated macrophages (TAMs) in GBM and disease-associated microglia (DAMs) in AD. These pathways are critical to the processes of neuroinflammation, angiogenesis, and apoptosis, which are hallmarks of GBM and AD. We concentrate on the multifaceted regulation of TAMs by NF-κB signaling in GBM, the influence of TREM2 on DAMs' responses to amyloid-beta deposition, and the modulation of both TAMs and DAMs by GBM- and AD-related miRNAs. Incorporating recent advancements in molecular biology, immunology, and AI techniques, through a detailed exploration of these molecular mechanisms, we aim to shed light on their distinct and overlapping regulatory functions in GBM and AD. The review culminates with a discussion on how insights into NF-κB, miRNAs, and TREM2 signaling may inform novel therapeutic approaches targeting microglia and macrophages in these neurodegenerative and neoplastic conditions. This comparative analysis underscores the potential for new, targeted treatments, offering a roadmap for future research aimed at mitigating the progression of these complex diseases.

Insights into the Tumor Microenvironment-Components, Functions and Therapeutics

Similarly to our healthy organs, the tumor tissue also constitutes an ecosystem. This implies that stromal cells acquire an altered phenotype in tandem with tumor cells, thereby promoting tumor survival. Cancer cells are fueled by abnormal blood vessels, allowing them to develop and proliferate. Tumor-associated fibroblasts adapt their cytokine and chemokine production to the needs of tumor cells and alter the peritumoral stroma by generating more collagen, thereby stiffening the matrix; these processes promote epithelial-mesenchymal transition and tumor cell invasion. Chronic inflammation and the mobilization of pro-tumorigenic inflammatory cells further facilitate tumor expansion. All of these events can impede the effective administration of tumor treatment; so, the successful inhibition of tumorous matrix remodeling could further enhance the success of antitumor therapy. Over the last decade, significant progress has been made with the introduction of novel immunotherapy that targets the inhibitory mechanisms of T cell activation. However, extensive research is also being conducted on the stromal components and other cell types of the tumor microenvironment (TME) that may serve as potential therapeutic targets.

Lapachol inhibits the growth of lung cancer by reversing M2-like macrophage polarization via activating NF-κB signaling pathway

Resetting tumor-associated macrophages (TAMs) is a promising strategy to ameliorate the immunosuppressive tumor microenvironment (TME) and improve innate and adaptive antitumor immunity. Lapachol, a naturally occurring 1,4-naphthoquinone, exhibits various pharmacological activities including antitumor, anti-leishmanial, antimalarial and antiseptic. In this study, we investigated the relevance of macrophage polarization and the antitumor effect of lapachol in Lewis lung cancer (LLC) both in vitro and in vivo. This study demonstrated that lapachol significantly reversed the polarization of M2-like macrophages thus that were endowed with the ability to kill LLC cells by activating NF-κB signaling pathway. Furthermore, lapachol effectively suppressed tumor growth in C57BL/6 mice bearing lung tumors by reducing the proportion of M2-like macrophages. Overall, our findings clearly illustrated that lapachol could reverse the polarization of M2-like macrophages to improve the immunosuppressive tumor microenvironment, and had the potential to be developed as an immunomodulatory antitumor agent.

The CAR macrophage cells, a novel generation of chimeric antigen-based approach against solid tumors

Today, adoptive cell therapy has many successes in cancer therapy, and this subject is brilliant in using chimeric antigen receptor T cells. The CAR T cell therapy, with its FDA-approved drugs, could treat several types of hematological malignancies and thus be very attractive for treating solid cancer. Unfortunately, the CAR T cell cannot be very functional in solid cancers due to its unique features. This treatment method has several harmful adverse effects that limit their applications, so novel treatments must use new cells like NK cells, NKT cells, and macrophage cells. Among these cells, the CAR macrophage cells, due to their brilliant innate features, are more attractive for solid tumor therapy and seem to be a better candidate for the prior treatment methods. The CAR macrophage cells have vital roles in the tumor microenvironment and, with their direct effect, can eliminate tumor cells efficiently. In addition, the CAR macrophage cells, due to being a part of the innate immune system, attended the tumor sites. With the high infiltration, their therapy modulations are more effective. This review investigates the last achievements in CAR-macrophage cells and the future of this immunotherapy treatment method.

Improving the therapeutic efficacy of oncolytic viruses for cancer: targeting macrophages

Oncolytic viruses (OVs) for cancer treatment are in a rapid stage of development, and the direct tumor lysis and activation of a comprehensive host immune response are irreplaceable advantages of cancer immunotherapy. However, excessive antiviral immune responses also restrict the spread of OVs in vivo and the infection of tumor cells. Macrophages are functionally diverse innate immune cells that phagocytose tumor cells and present antigens to activate the immune response, while also limiting the delivery of OVs to tumors. Studies have shown that the functional propensity of macrophages between OVs and tumor cells affects the overall therapeutic effect of oncolytic virotherapy. How to effectively avoid the restrictive effect of macrophages on OVs and reshape the function of tumor-associated macrophages in oncolytic virotherapy is an important challenge we are now facing. Here, we review and summarize the complex dual role of macrophages in oncolytic virotherapy, highlighting how the functional characteristics of macrophage plasticity can be utilized to cooperate with OVs to enhance anti-tumor effects, as well as highlighting the importance of designing and optimizing delivery modalities for OVs in the future.

Endogenous H2O2 Self-Replenishment and Sustainable Cascades Enhance the Efficacy of Sonodynamic Therapy

Purpose

Sonodynamic therapy (SDT), with its high tissue penetration and noninvasive advantages, represents an emerging approach to eradicating solid tumors. However, the outcomes of SDT are typically hampered by the low oxygen content and immunosuppression in the tumor microenvironment (TME). Accordingly, we constructed a cascade nanoplatform to regulate the TME and improve the anti-tumor efficiency of SDT.

Methods

In this study, we rationally design cascade nanoplatform by incorporating immunostimulant hyaluronic acid (HA) and sonosensitizer chlorin e6 (Ce6) on the polydopamine nanocarrier that is pre-doped with platinum nanozymes (designated Ce6/Pt@PDA-HA, PPCH).

Results

The cascade reactions of PPCH are evidenced by the results that HA exhibits reversing immunosuppressive that converts M2 macrophages into M1 macrophages in situ, while producing H2O2, and then platinum nanozymes further catalyze the H2O2 to produce O2, and O2 produces abundant singlet oxygen (1O2) under the action of Ce6 and low-intensity focused ultrasound (LIFU), resulting in a domino effect and further amplifying the efficacy of SDT. Due to its pH responsiveness and mitochondrial targeting, PPCH effectively accumulates in tumor cells. Under LIFU irradiation, PPCH effectively reverses immunosuppression, alleviates hypoxia in the TME, enhances reactive oxygen species (ROS) generation, and enhances SDT efficacy for eliminating tumor cells in vivo and in vitro. Meanwhile, an in vivo dual-modal imaging including fluorescence and photoacoustic imaging achieves precise tumor diagnosis.

Conclusion

This cascade nanoplatform will provide a promising strategy for enhancing SDT eradication against tumors by modulating immunosuppression and relieving hypoxia.

Comprehensive analysis of resistance mechanisms to EGFR-TKIs and establishment and validation of prognostic model

PURPOSE

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are the first-line therapy for patients with lung adenocarcinoma (LUAD) harboring activating EGFR mutations. However, the emergence of drug resistance to EGFR-TKIs remains a critical obstacle for successful treatment and is associated with poor patient outcomes. The overarching objective of this study is to apply bioinformatics tools to gain insights into the mechanisms underlying resistance to EGFR-TKIs and develop a robust predictive model.

METHODS

The genes associated with gefitinib resistance in the LUAD cell Gene Expression Omnibus (GEO) database were identified using gene chip expression data. Functional enrichment analysis, gene set enrichment analysis (GSEA), and immune infiltration analysis were performed to comprehensively explore the mechanism of gefitinib resistance. Furthermore, a GRRG_score was constructed by integrating genes related to LUAD prognosis from The Cancer Genome Atlas (TCGA) database with the screened Gefitinib Resistant Related differentially expressed genes (GRRDEGs) using the Least Absolute Shrinkage and Selection Operator (LASSO) and Cox regression analyses. Furthermore, we conducted an in-depth analysis of the tumor microenvironment (TME) features and their association with immune infiltration between different GRRG_score groups. A prognostic model for LUAD was developed based on the GRRG_score and validated. The HPA database was used to validate protein expression. The CTR-DB database was utilized to validate the results of drug therapy prediction based on the relevant genes.

RESULTS

A total of 110 differentially expression genes were identified. Pathway enrichment analysis of DEGs showed that the differentially expressed genes were mainly enriched in Mucin type O-glycan biosynthesis, Cytokine-cytokine receptor interaction, Sphingolipid metabolism. Gene set enrichment analysis showed that biological processes strongly correlated with gefitinib resistance were cell proliferation and immune-related pathways, EPITHELIAL_MESENCHYMAL_TRANSITION, APICAL_SURFACE, and APICAL_JUNCTION were highly expressed in the drug-resistant group; KRAS_SIGNALING_DN, HYPOXIA, and HEDGEHOG_SIGNALING were highly expressed in the drug-resistant group. The GRRG_score was constructed based on the expression levels of 13 genes, including HSPA2, ATP8B3, SPOCK1, EIF6, NUP62CL, BCAR3, PCSK9, NT5E, FLNC, KRT8, FSCN1, ANGPTL4, and ID1. We further screened and validated two key genes, namely, NUP62CL and KRT8, which exhibited predictive value for both prognosis and drug resistance.

CONCLUSIONS

Our study identified several novel GRRDEGs and provided insight into the underlying mechanisms of gefitinib resistance in LUAD. Our results have implications for developing more effective treatment strategies and prognostic models for LUAD patients.

CXCL8 induces M2 macrophage polarization and inhibits CD8+ T cell infiltration to generate an immunosuppressive microenvironment in colorectal cancer

The poor prognosis of immunotherapy in patients with colorectal cancer (CRC) necessitates a comprehensive understanding of the immunosuppressive mechanisms within tumor microenvironment (TME). Undoubtedly, the anti-tumor immune cells play an indispensable role in immune tolerance. Therefore, it is imperative to investigate novel immune-related factors that have the capacity to enhance anti-tumor immunity. Here, we employed bioinformatic analysis using R and Cytoscape to identify the hub gene chemokine (C-X-C motif) ligand 8 (CXCL8), which is overexpressed in CRC, in the malignant progression of CRC. However, its specific role of CXCL8 in CRC immunity remains to be elucidated. For this purpose, we evaluated how tumor-derived CXCL8 promotes M2 macrophage infiltration by in vivo and in vitro, which can be triggered by IL-1β within TME. Mechanistically, CXCL8-induced polarization of M2 macrophages depends on the activation of the STAT3 signaling. Finally, immunohistochemistry and multiplexed immunohistochemistry analysis identified that CXCL8 not only enhances PD-L1+ M2 macrophage infiltration but also attenuates the recruitment of PD-1+ CD8+ T cells in murine CRC models. Together, these findings emphasize the critical role for CXCL8 in promoting M2 macrophage polarization and inhibiting CD8+ T cell infiltration, thereby links CXCL8 to the emergency of immunosuppressive microenvironment facilitating tumor evasion. Overall, these findings may provide novel strategy for CRC immunotherapy.

Evaluation of CD47 in the Suppressive Tumor Microenvironment and Immunotherapy in Prostate Cancer

Background

CD47 has high levels of expression in malignant cancer cells, which binds to SIRP-α to release the "don't eat me" signal and prevents mononuclear macrophages from phagocytosing the cells. Resistance to drugs and metastases are potential barriers for prostate cancer endocrine therapy. Although immunotherapy for tumors has developed rapidly in the last few decades, its effectiveness in treating prostate cancer is unsatisfactory. Prostate cancer has a high-expression level of CD47. Therefore, a novel approach for potential immunotherapy may be provided by investigating the relationship among CD47 and the infiltration of immune cells in the prostate carcinoma.

Methods

The GEPIA database was utilized to compare the abundance of CD47 in malignant tissues with tissues that were normal. Furthermore, the function of CD47 in prostate carcinoma was assessed by CancerSEA. The association among CD47 and the tumor microenvironment was assessed utilizing the TISCH single cell data database. By using TIMER, the connection among CD47 and immunological invasion of prostate cancer was explored. Moreover, macrophages were cocultured with mouse prostate cancer cell RM-1 blocked by CD47 antibody to observe the changes in phagocytosis efficiency in vitro.

Results

Expression level of CD47 is upregulated in prostate carcinoma, and it is closely connected with prostate cancer's inadequate immune invasion. CD47 antibody blocking promotes macrophage phagocytosis of RM-1.

Conclusion

Our research demonstrates a closely relationship among CD47 and the immunological microenvironment of prostate cancer, and blocking CD47 can promote macrophages to phagocytosis of prostate cancer cells. Therefore, CD47 may provide novel strategies for potential immunotherapy of prostate cancer.

PEG-Sheddable Nanodrug Remodels Tumor Microenvironment to Promote Effector T Cell Infiltration and Revise Their Exhaustion for Breast Cancer Immunotherapy

Low infiltration of cytotoxic T lymphocytes and their exhaustion manifest the two concurrent main hurdles for achieving effective tumor immunotherapy of triple-negative breast cancer. It is found that Galectin-9 blockage can revise the exhaustion of effector T cells, meanwhile the repolarization of protumoral M2 tumor-associated macrophages (TAMs) into tumoricidal M1-like ones can recruit effector T cells infiltrating into tumor to boost immune responses. Herein, a sheddable PEG-decorated and M2-TAMs targeted nanodrug incorporating Signal Transducer and Activator of Transcription 6 inhibitor (AS) and anti-Galectin-9 antibody (aG-9) is prepared. The nanodrug responds to acidic tumor microenvironment (TME) with the shedding of PEG corona and the release of aG-9, exerting local blockade of PD-1/Galectin-9/TIM-3 interaction to augment effector T cells via exhaustion reversing. Synchronously, targeted repolarization of M2-TAMs into M1 phenotype by AS-loaded nanodrug is achieved, which promotes tumor infiltration of effector T cells and thus synergizes with aG-9 blockade to boost the therapeutic efficacy. Besides, the PEG-sheddable approach endows nanodrug with stealth ability to reduce immune-related adverse effects caused by AS and aG-9. This PEG sheddable nanodrug holds the potential to reverse the immunosuppressive TME and increase effector T cell infiltration, which dramatically enhances immunotherapy in highly malignant breast cancer.

Lymph node metastasis and tumor-educated immune tolerance: Potential therapeutic targets against distant metastasis

Lymph node metastasis has been shown to positively associated with the prognosis of many cancers. However, in clinical treatment, lymphadenectomy is not always successful, suggesting that immune cells in the tumor and sentinel lymph nodes still play a pivotal role in tumor immunosuppression. Recent studies had shown that tumors can tolerate immune cells through multiple strategies, including tumor-induced macrophage reprogramming, T cells inactivation, production of B cells pathogenic antibodies and activation of regulatory T cells to promote tumor colonization, growth, and metastasis in lymph nodes. We reviewed the bidirectional effect of immune cells on anti-tumor or promotion of cancer cell metastasis during lymph node metastasis, and the mechanisms by which malignant cancer cells modify immune cells to create a more favorable environment for the growth and survival of cancer cells. Research and treatment strategies focusing on the immune system in lymph nodes and potential immune targets in lymph node metastasis were also be discussed.

Chimeric Peptide Engineered Bioregulator for Metastatic Tumor Immunotherapy through Macrophage Polarization and Phagocytosis Restoration

Tumor-associated macrophages (TAMs) are the most abundant immune cells in solid tumor tissues, which restrict antitumor immunity by releasing tumor-supporting cytokines and attenuating phagocytosis behaviors. In this work, a chimeric peptide engineered bioregulator (ChiP-RS) is constructed for tumor immunotherapy through macrophage polarization and phagocytosis restoration. ChiP-RS is fabricated by utilizing macrophage-targeting chimeric peptide (ChiP) to load Toll-like receptor agonists (R848) and Src homology 2 (SH2) domain-containing protein tyrosine phosphatase 2 (SHP-2) inhibitor (SHP099). Among which, ChiP-RS prefers to be internalized by TAMs, repolarizing M2 macrophages into M1 macrophages to reverse the immunosuppressive microenvironment. In addition, SHP-2 can be downregulated to promote phagocytotic elimination behaviors of M1 macrophages, which will also activate T cell-based antitumor immunity for metastatic tumor therapy. In vitro and in vivo findings demonstrate a superior suppression effect of ChiP-RS against metastatic tumors without systemic side effects. Such a simple but effective nanoplatform provides sophisticated synergism for immunotherapy, which may facilitate the development of translational nanomedicine for metastatic tumor treatment.