Reprogramming of TAMs via the STAT3/CD47-SIRPα axis promotes acquired resistance to EGFR-TKIs in lung cancer

Biological mechanisms and immunotherapy of brain metastases in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related mortality worldwide, with Brain Metastases serving as a significant adverse prognostic factor. The blood-brain barrier poses a substantial challenge in the treatment of brain metastases, as it restricts the penetration of many anticancer agents. Novel immunotherapy, such as immune checkpoint inhibitors (ICIs) have emerged as promising treatment for NSCLC and its associated brain metastases. This review summarizes the biological mechanism underlying NSCLC brain metastases and provides an overview of the current landscape of immunotherapy, exploring the mechanism of action and clinical applications of these advanced treatments.

Dual cytokine-engineered macrophages rejuvenate the tumor microenvironment and enhance anti-PD-1 therapy in renal cell carcinoma

Despite advances in PD-1 blockade therapy, the immunosuppressive tumor microenvironment (TME) limits its efficacy in renal cell carcinoma (RCC). Here, we developed dual-cytokine-engineered macrophages co-delivering IL-12 and CXCL-9 to reprogram TME and enhance anti-PD-1 responsiveness. Single-cell RNA sequencing revealed that RCC harbor abundant M2-like tumor-associated macrophages (TAMs), which correlate with T-cell exhaustion. In vitro, engineered macrophages polarized M2-like TAMs to antitumor M1 phenotypes, secreted CXCL-9 to recruit cytotoxic T cells, and released IL-12 to amplify T/NK cell activation. In vivo, intravenously administered engineered macrophages homed to tumors, reshaped the TME by increasing CD8+ T cells, dendritic cells, and NK cells while reducing immunosuppressive Tregs and MDSCs. This approach synergized with PD-1 blockade, resulting in a 2.5-fold greater tumor growth inhibition compared to anti-PD-1 monotherapy. This dual-cytokine macrophage platform offers a novel strategy to overcome resistance to checkpoint inhibitors in RCC by delivering cytokine and remodeling TME, with implications for clinical translation.

m6A modification-dependent upregulation of WNT2 facilitates M2-like macrophage polarization and perpetuates malignant progression of nasopharyngeal carcinoma

The development and progression of nasopharyngeal carcinoma (NPC) involves intricate interactions between tumor cells and other surrounding cells in the tumor microenvironment (TME). Tumor-associated macrophages (TAMs) play pivotal roles in the progression of NPC, but their interactions remain largely unexplored. In this study, we revealed that NPC promoted M2-like polarization of TAMs through enhanced synthesis and secretion of WNT2. These M2-type macrophages, in turn, significantly boosted the proliferation and metastasis of NPC. This vicious cycle perpetuated the malignant progression of NPC. Mechanistically, elevated m6A modification of WNT2 in NPC stabilized its mRNA and facilitated its protein expression, which is coordinately regulated by the m6A "eraser" ALKBH5 and the "reader" YTHDF1. NPC promoted M2-like polarization of macrophages by activating the FZD2/β-catenin signaling axis through paracrine WNT2. Furthermore, elevated WNT2 can also trigger the WNT/β-catenin signaling pathway in NPC cells through autocrine signaling, synergically contributing to NPC development. The research reveals that WNT2 is upregulated in an m6A modification-dependent manner and promotes M2-like macrophages polarization of TAMs and malignant progression of NPC. This discovery provides novel potential molecular markers and therapeutic targets for the diagnosis and treatment of NPC.

Drug-induced tolerant persisters in tumor: mechanism, vulnerability and perspective implication for clinical treatment

Cancer remains a significant global health burden due to its high morbidity and mortality. Oncogene-targeted therapy and immunotherapy have markedly improved the 5-year survival rate in the patients with advanced or metastatic tumors compared to outcomes in the era of chemotherapy/radiation. Nevertheless, the majority of patients remain incurable. Initial therapies eliminate the bulk of tumor cells, yet residual populations termed drug-tolerant persister cells (DTPs) survive, regenerate tumor and even drive distant metastases. Notably, DTPs frequently render tumor cross-resistance, a detrimental phenomenon observed in the patients with suboptimal responses to subsequent therapies. Analogous to species evolution, DTPs emerge as adaptative products at the cellular level, instigated by integrated intracellular stress responses to therapeutic pressures. These cells exhibit profound heterogeneity and adaptability shaped by the intricate feedforward loops among tumor cells, surrounding microenvironments and host ecology, which vary across tumor types and therapeutic regimens. In this review, we revisit the concept of DTPs, with a focus on their generation process upon targeted therapy or immunotherapy. We dissect the critical phenotypes and molecule mechanisms underlying DTPs to therapy from multiple aspects, including intracellular events, intercellular crosstalk and the distant ecologic pre-metastatic niches. We further spotlight therapeutic strategies to target DTP vulnerabilities, including synthetic lethality approaches, adaptive dosing regimens informed by mathematical modeling, and immune-mediated eradication. Additionally, we highlight synergistic interventions such as lifestyle modifications (e.g., exercise, stress reduction) to suppress pro-tumorigenic inflammation. By integrating mechanistic insights with translational perspectives, this work bridges the gap between DTP biology and clinical strategies, aiming for optimal efficacy and preventing relapse.

Targeting Tumor-Associated Macrophage Polarization with Traditional Chinese Medicine Active Ingredients: Dual Reversal of Chemoresistance and Immunosuppression in Tumor Microenvironment

Chemotherapy resistance and immunosuppression are major causes of tumor treatment failure. The polarization state of tumor-associated macrophages (TAMs) is a central regulatory hub for both processes. Traditional Chinese medicine (TCM) has the characteristics of multi-component, multi-target, and multi-pathway. It regulating M1/M2 polarization is promising due to the high plasticity of TAMs. This review comprehensively explores the anti-tumor effects of TCM active components through multiple targets such as metabolic reprogramming. The mechanism includes regulating TAM's polarization, reversing chemotherapy resistance, and modulating immunosuppression. Furthermore, we also summarize the synergistic effects of TCM multi-component and the exploration of mechanisms promoted by new technologies. While most studies are still in the preclinical stage, these insights highlight the potential of TCM as a cancer treatment and highlight avenues for future research and clinical application to improve patient outcomes.

Lung tumor immunity: redirecting macrophages through infection-induced inflammation

Macrophages play a central role in maintaining tissue homeostasis and in surveillance against pathogens and disease. In the lung, they can adopt either proinflammatory or anti-inflammatory states depending on the nature of the stimulus. As the predominant immune cells in both the lung tumor microenvironment and in sites of lung infection, the functional plasticity of macrophages makes them key players in determining disease outcome. Accurately defining their inflammatory profiles offers an opportunity to reprogram infection-associated macrophages towards enhanced tumor-killing phenotypes. This review explores how acute inflammation can drive macrophage-mediated antitumor immunity and highlights key molecules and signaling pathways that may be leveraged to therapeutically modulate macrophage function.

Radiation-induced amphiregulin drives tumour metastasis

The anti-tumour effect of radiotherapy beyond the treatment field-the abscopal effect-has garnered much interest1. However, the potentially deleterious effect of radiation in promoting metastasis is less well studied. Here we show that radiotherapy induces the expression of the EGFR ligand amphiregulin in tumour cells, which reprogrammes EGFR-expressing myeloid cells toward an immunosuppressive phenotype and reduces phagocytosis. This stimulates distant metastasis growth in human patients and in pre-clinical mouse tumour models. The inhibition of these tumour-promoting factors induced by radiotherapy may represent a novel therapeutic strategy to improve patient outcomes.

PD-1 regulates the anti-tumor immune function of macrophages through JAK2-STAT3 signaling pathway in colorectal cancer tumor microenvironment

BACKGROUND

Tumor-associated macrophages (TAMs), as key immune components of the TME, play a pivotal role in tumor progression by fostering an immunosuppressive environment. Programmed death 1 (PD-1), a critical immune checkpoint molecule predominantly expressed on T cells, mediates immune suppression by binding to programmed death-ligand 1 (PD-L1) on tumor cells within the tumor microenvironment (TME). Emerging evidence reveals that TAMs also express PD-1, however, the expression and functional regulatory mechanisms of PD-1 on TAM remain poorly understood.

METHODS

In this study, we combined bulk RNA sequencing and single-cell RNA sequencing (scRNA-seq) data to investigate the association between PD-1 expression on macrophages and patient prognosis, while also uncovering the molecular mechanisms by which PD-1 regulates macrophage function. To further investigate the role of PD-1 in macrophage activity, we established a fluorescence-labeled tumor-bearing mouse model using CT26 cells, a murine colorectal cancer cell line, to evaluate the relationship between PD-1 expression on TAMs and their phagocytic activity as well as other functions. Additionally, to mimic the TME in vitro, we cultured bone marrow-derived macrophages (BMDMs) with CT26-conditioned medium (CT26-CM).

RESULTS

Our results suggest that PD-1 expression on TAMs drives macrophage polarization toward an M2-like phenotype, suppresses their phagocytic activity, inhibits the synthesis of interferon-γ (IFN-γ) signaling molecules, and ultimately promotes tumor progression. Mechanistically, we demonstrated that PD-1 regulates the synthesis of IFN-γ signaling molecules and the polarization of M2-type macrophages in BMDMs through the JAK2-STAT3 signaling pathway. Overall, our study demonstrates that PD-1 expression on TAMs facilitates the formation of an immunosuppressive microenvironment, ultimately accelerating tumor progression.

CLINICAL TRIAL NUMBER

Not applicable.

Strategies Beyond 3rd EGFR-TKI Acquired Resistance: Opportunities and Challenges

The seminal identification of epidermal growth factor receptor (EGFR) mutations as pivotal oncogenic drivers in non-small cell lung cancer (NSCLC) has catalyzed the evolution of biomarker-guided therapeutic paradigms for advanced disease. Currently, third-generation EGFR tyrosine kinase inhibitors (EGFR-TKI) have revolutionized first-line treatment for advanced EGFR-mutated NSCLC, yet acquired resistance remains an inevitable and formidable clinical challenge. This review systematically summarizes molecular mechanisms underlying treatment resistance, with a focus on clinical challenges associated with central nervous system (CNS) metastases. Therapeutic resistance mechanisms are categorized into EGFR-dependent (on-target) pathways, typified by acquired kinase domain mutations (e.g., C797S), and EGFR-independent (off-target) pathways, involving compensatory activation of parallel signaling effectors (e.g., MET amplification, HER2 activation) or phenotypic transformation. We further evaluated contemporary diagnostic modalities for identifying resistance drivers and appraised emerging therapeutic strategies, including fourth-generation EGFR-TKI, various combination therapies, and antibody-drug conjugates (ADCs), and so forth, with emphasis on ongoing clinical trials that may transform the existing treatment paradigm. By synthesizing preclinical and clinical insights, this review aims to advance mechanistic understanding and propose therapeutic strategies to overcome acquired resistance to third-generation EGFR-TKI in first-line treatment.

The clinical significance and potential therapeutic target of tumor-associated macrophage in non-small cell lung cancer

One of the leading causes of cancer-related mortality globally is non-small cell lung cancer (NSCLC). It has become a significant public health concern due to its rising incidence rate and fatality. Tumor-associated macrophage (TAM) is important in the tumor microenvironment (TME) of NSCLC because they have an impact on the development, metastasis, and incidence of tumors. As a crucial element of the TME, TAM contributes to tumor immune evasion, facilitates tumor proliferation and metastasis, and modulates tumor angiogenesis, immunosuppression, and treatment resistance through the secretion of diverse cytokines, chemokines, and growth factors. Consequently, TAM assumes a multifaceted and intricate function in the onset, progression, and therapeutic response of NSCLC, serving as a crucial focal point for comprehending the tumor microenvironment and formulating novel therapeutic methods. The study aims to review the biological properties and potential processes of TAM in NSCLC, investigate its involvement in the clinical of NSCLC patients, and discuss its potential as a therapeutic target.

CD47 Contributes to the Proliferation of Breast Cancer

BACKGROUND

The CD47 molecule (CD47) performs a novel role in regulating immunoreactions by binding to signal-regulatory protein alpha (SIRPα), resulting in the tumorigenesis of multiple malignant neoplasms. However, its effects and mechanisms in breast cancer (BC) remain unknown.

METHODS

To explore the molecular mechanisms and explicit impacts of CD47, we screened two databases for CD47-associated signaling pathways and cellular functions. BC samples and patients' basic information were collected to identify the statistical significance of CD47 expression. We also constructed experiments to validate the regulatory role of CD47 in BC cell proliferation.

RESULTS

Analysis of the TCGA-BRCA, GSE42568, and GSE15852 datasets demonstrated an elevated level of CD47 in BC tissues. A Venn diagram revealed 11,194 co-expressed genes, and pathway analysis linked elevated CD47 levels to critical signaling pathways, such as cytokine-receptor interactions and Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling, which are integral to cell proliferation and invasiveness. Clinical data from 108 BC specimens showed that CD47 localization was primarily membranous, with higher levels correlating with proliferation marker Ki-67 (Ki-67) expression (p < 0.0001) and advanced tumor/node/metastasis (TNM) stage (p < 0.0001). Additionally, functional assays demonstrated that CD47 depletion reduced cell viability (p < 0.01), migration (p < 0.001), and invasion (p < 0.05 in 4T1 cells; p < 0.001 in MDA-MB-231 cells) in vitro and led to smaller tumor volumes (p < 0.0001) in vivo.

CONCLUSION

CD47 is a key regulator of BC cell proliferation and invasiveness and serves as a potential marker for assessing tumor aggressiveness and guiding therapeutic strategies.

Therapeutic Potential of IL-37 in Cervical Cancer: Suppression of Tumour Progression and Enhancement of CD47-Mediated Macrophage Phagocytosis

As a promising therapeutic approach, immunotherapy is being extensively investigated in cervical cancer. Although immunotherapy has been validated to improve progression-free survival and overall survival in clinical trials, the overall response rate for cervical cancer remains inadequate, necessitating further improvement. Interleukin (IL)-37, an emerging immunomodulator, exhibits antitumour potentials by inhibiting tumour progression and regulating tumour-associated macrophage recognition. We found a significant downregulation of IL-37 expression in cervical cancer, correlated with a poor prognosis. Moreover, the upregulation of IL-37 expression exhibited a suppressive effect on various tumorigenic processes, suppressing the proliferation, invasion, migration, apoptosis and angiogenesis of tumour cells. We also found that the upregulation of IL-37 suppressed cluster of differentiation 47 (CD47) expression in tumour cells via suppression of the signal transducer and activator of transcription 3 (STAT3) expression and phosphorylation, thereby enhancing macrophage recognition and phagocytosis to tumour cells, ultimately reducing immune evasion. Overall, our study highlighted the crucial role of IL-37 in antitumour efficacy and downregulating the expression of CD47 in tumour cells to reduce immune evasion, suggesting the potential of IL-37 as a prognostic biomarker in cervical cancer and offering innovative therapeutic strategies to improve cancer treatment outcomes.

The role of tumor-associated macrophages in lung cancer

Lung cancer remains a leading cause of cancer-related deaths worldwide, necessitating innovative treatments. Tumor-associated macrophages (TAMs) are primary immunosuppressive effectors that foster tumor proliferation, angiogenesis, metastasis, and resistance to therapy. They are broadly categorized into proinflammatory M1 and tumor-promoting M2 phenotypes, with elevated M2 infiltration correlating with poor prognosis. Strategies aimed at inhibiting TAM recruitment, depleting TAMs, or reprogramming M2 to M1 are therefore highly promising. Key signaling pathways, such as CSF-1/CSF-1R, IL-4/IL-13-STAT6, TLRs, and CD47-SIRPα, regulate TAM polarization. Additionally, macrophage-based drug delivery systems permit targeted agent transport to hypoxic regions, enhancing therapy. Preclinical studies combining TAM-targeted therapies with chemotherapy or immune checkpoint inhibitors have yielded improved responses and prolonged survival. Several clinical trials have also reported benefits in previously unresponsive patients. Future work should clarify the roles of macrophage-derived exosomes, cytokines, and additional mediators in shaping the immunosuppressive tumor microenvironment. These insights will inform the design of next-generation drug carriers and optimize combination immunotherapies within precision medicine frameworks. Elucidating TAM phenotypes and their regulatory molecules remains central to developing novel strategies that curb tumor progression and ultimately improve outcomes in lung cancer. Importantly, macrophage-based immunomodulation may offer expanded treatment avenues.

Single-Cell RNA Sequencing in Unraveling Acquired Resistance to EGFR-TKIs in Non-Small Cell Lung Cancer: New Perspectives

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have demonstrated remarkable efficacy in treating non-small cell lung cancer (NSCLC), but acquired resistance greatly reduces efficacy and poses a significant challenge to patients. While numerous studies have investigated the mechanisms underlying EGFR-TKI resistance, its complexity and diversity make the existing understanding still incomplete. Traditional approaches frequently struggle to adequately reveal the process of drug resistance development through mean value analysis at the overall cellular level. In recent years, the rapid development of single-cell RNA sequencing technology has introduced a transformative method for analyzing gene expression changes within tumor cells at a single-cell resolution. It not only deepens our understanding of the tumor microenvironment and cellular heterogeneity associated with EGFR-TKI resistance but also identifies potential biomarkers of resistance. In this review, we highlight the critical role of single-cell RNA sequencing in lung cancer research, with a particular focus on its application to exploring the mechanisms of EGFR-TKI-acquired resistance in NSCLC. We emphasize its potential for elucidating the complexity of drug resistance mechanism and its promise in informing more precise and personalized treatment strategies. Ultimately, this approach aims to advance NSCLC treatment toward a new era of precision medicine.

AXL: shapers of tumor progression and immunosuppressive microenvironments

As research progresses, our understanding of the tumor microenvironment (TME) has undergone profound changes. The TME evolves with the developmental stages of cancer and the implementation of therapeutic interventions, transitioning from an immune-promoting to an immunosuppressive microenvironment. Consequently, we focus intently on the significant role of the TME in tumor proliferation, metastasis, and the development of drug resistance. AXL is highly associated with tumor progression; however, previous studies on AXL have been limited to its impact on the biological behavior of cancer cells. An increasing body of research now demonstrates that AXL can influence the function and differentiation of immune cells, mediating immune suppression and thereby fostering tumor growth. A comprehensive analysis to identify and overcome the causes of immunosuppressive microenvironments represents a novel approach to conquering cancer. In this review, we focus on elucidating the role of AXL within the immunosuppressive microenvironments, discussing and analyzing the effects of AXL on tumor cells, T cells, macrophages, natural killer (NK) cells, fibroblasts, and other immune-stromal cells. We aim to clarify the contributions of AXL to the progression and drug resistance of cancer from its functional role in the immune microenvironment.

Reprogramming tumor-associated macrophages: The role of MEK-STAT3 inhibition in lung cancer

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

APOC1 inhibit NKTCL doxorubicin sensitivity by promoting mitophagy

NKTCL is a highly aggressive malignant tumor, especially prevalent in the southern regions of China. Although chemotherapy regimens based on ADM have achieved certain therapeutic effects in early treatment, the issue of ADM resistance severely limits the therapeutic efficacy and makes it difficult to improve patient survival rates. Our research results indicate that the expression level of APOC1 is closely related to the sensitivity of NKTCL cells to ADM. The upregulation of APOC1 may promote mitophagy, clear damaged mitochondria, stabilize the intracellular environment, and enhance the tolerance of tumor cells to ADM. Furthermore, APOC1 may further affect the formation of mitophagy and drug resistance by activating specific signaling pathways, such as the STAT3 signaling pathway. Animal experiments further confirm the conclusions of in vitro experiments, showing that APOC1 regulates mitophagy through p-STAT3Tyr705, thereby promoting the drug resistance of NKTCL. These findings provide a new perspective for the development of novel therapeutic strategies targeting APOC1 and its associated signaling pathways, which may help overcome the issue of ADM resistance in NKTCL.

PRKDC regulates cGAMP to enhance immune response in lung cancer treatment

Background

Despite its involvement in nucleotide metabolism, tumor immune landscape, and immunotherapy response, the role of 2'-3'-cyclic guanosine monophosphate-adenosine monophosphate (2',3'-cGAMP) in lung adenocarcinoma (LUAD) remails unelucidated. This study aimed to investigate the antitumor effects of 2',3'-cGAMP in LUAD.

Method

Herein, patients with LUAD were screened for prognostic biomarkers, which were then assessed for sensitivity to immunotherapy and chemotherapy utilizing the "TIDE" algorithm and CellMiner database. The results were validated using a mouse xenograft model. Additionally, macrophages and lung cancer cells were co-cultured, and macrophage polarization and apoptosis levels in the lung cancer cells were detected through flow cytometry. Protein levels were analyzed through western blotting and immunofluorescence. Finally, drug-encapsulated nanoparticles were designed to systematically examine the antitumor efficacy of the treatment against LUAD.

Result

Notably, 2',3'-cGAMP-mediated protein kinase, DNA-activated, catalytic subunit (PRKDC) inhibition induced macrophage polarization toward the M1 phenotype, thereby triggering apoptosis in LUAD cells. Furthermore, in vivo experiments showed that M1 macrophage infiltration enhancement and apoptosis induction in lung cancer cells were achieved by suppressing PRKDC expression via 2',3'-cGAMP, which inhibited lung cancer growth. The machine-learning approaches revealed SB505124 to be an effective antitumor agent in LUAD cells with high PRKDC levels owing to its ability to promote 2',3'-cGAMP-mediated apoptosis. Encapsulation of 2',3'-cGAMP, and SB505124 within a nano-delivery system markedly reduced tumor volumes in murine lung cancer tissues compared with that by individual agents.

Conclusion

The findings of this study reveal that PRKDC can predict poor survival of patients with LUAD. Additionally, SB505124 enhances the efficacy of 2',3'-cGAMP-based immunotherapy in patients exhibiting a high PRKDC expression.

Predicting the Recurrence of Ovarian Cancer Based on Machine Learning

Background

Recurrence is the main factor for poor prognosis in ovarian cancer, but few prognostic biomarkers were reported. In this study, we used machine learning methods based on multiple biomarkers to develop a specific prediction model for the recurrence of ovarian cancer.

Methods

A total of 277 ovarian cancer patients were enrolled in this study and randomly classified into training and testing cohorts. The prediction information was obtained through 47 clinical parameters using six supervised clustering machine learning algorithms, including K-Nearest Neighbor (K-NN), Decision Tree (DT), Random Forest (RF), Adaptive Boosting (AdaBoost), Gradient Boosting Machine (GBM), and Extreme Gradient Boosting (XGBoost).

Results

In predicting the recurrence of ovarian cancer, machine learning algorithm was superior to conventional logistic regression analysis. In this study, XGBoost showed the best performance in predicting the recurrence of ovarian cancer, with an accuracy of 0.95. In addition, neoadjuvant chemotherapy, Monocyte ratio (MONO%), Hematocrit (HCT), Prealbumin (PAB), Aspartate aminotransferase (AST), and carbohydrate antigen 125 (CA125) are the most important biomarkers to predict the recurrence of ovarian cancer.

Conclusion

The machine learning techniques can achieve a more accurate assessment of the recurrence of ovarian cancer, which can help clinicians make decisions, and develop personalized treatment strategies.

Shaping the immune landscape: Multidimensional environmental stimuli refine macrophage polarization and foster revolutionary approaches in tissue regeneration

In immunology, the role of macrophages extends far beyond their traditional classification as mere phagocytes; they emerge as pivotal architects of the immune response, with their function being significantly influenced by multidimensional environmental stimuli. This review investigates the nuanced mechanisms by which diverse external signals ranging from chemical cues to physical stress orchestrate macrophage polarization, a process that is crucial for the modulation of immune responses. By transitioning between pro-inflammatory (M1) and anti-inflammatory (M2) states, macrophages exhibit remarkable plasticity, enabling them to adapt to and influence their surroundings effectively. The exploration of macrophage polarization provides a compelling narrative on how these cells can be manipulated to foster an immune environment conducive to tissue repair and regeneration. Highlighting cutting-edge research, this review presents innovative strategies that leverage the dynamic interplay between macrophages and their environment, proposing novel therapeutic avenues that harness the potential of macrophages in regenerative medicine. Moreover, this review critically evaluates the current challenges and future prospects of translating macrophage-centered strategies from the laboratory to clinical applications.

Discovery of vitexin as a novel VDR agonist that mitigates the transition from chronic intestinal inflammation to colorectal cancer

Colitis-associated colorectal cancer (CAC) frequently develops in patients with inflammatory bowel disease (IBD) who have been exposed to a prolonged state of chronic inflammation. The investigation of pharmacological agents and their mechanisms to prevent precancerous lesions and inhibit their progression remains a significant focus and challenge in CAC research. Previous studies have demonstrated that vitexin effectively mitigates CAC, however, its precise mechanism of action warrants further exploration. This study reveals that the absence of the Vitamin D receptor (VDR) accelerates the progression from chronic colitis to colorectal cancer. Our findings indicate that vitexin can specifically target the VDR protein, facilitating its translocation into the cell nucleus to exert transcriptional activity. Additionally, through a co-culture model of macrophages and cancer cells, we observed that vitexin promotes the polarization of macrophages towards the M1 phenotype, a process that is dependent on VDR. Furthermore, ChIP-seq analysis revealed that vitexin regulates the transcriptional activation of phenazine biosynthesis-like domain protein (PBLD) via VDR. ChIP assays and dual luciferase reporter assays were employed to identify the functional PBLD regulatory region, confirming that the VDR/PBLD pathway is critical for vitexin-mediated regulation of macrophage polarization. Finally, in a mouse model with myeloid VDR gene knockout, we found that the protective effects of vitexin were abolished in mid-stage CAC. In summary, our study establishes that vitexin targets VDR and modulates macrophage polarization through the VDR/PBLD pathway, thereby alleviating the transition from chronic colitis to colorectal cancer.

Unveiling the contribution of tumor-associated macrophages in driving epithelial-mesenchymal transition: a review of mechanisms and therapeutic Strategies

Tumor-associated macrophages (TAMs), fundamental constituents of the tumor microenvironment (TME), significantly influence cancer development, primarily by promoting epithelial-mesenchymal transition (EMT). EMT endows cancer cells with increased motility, invasiveness, and resistance to therapies, marking a pivotal juncture in cancer progression. The review begins with a detailed exposition on the origins of TAMs and their functional heterogeneity, providing a foundational understanding of TAM characteristics. Next, it delves into the specific molecular mechanisms through which TAMs induce EMT, including cytokines, chemokines and stromal cross-talking. Following this, the review explores TAM-induced EMT features in select cancer types with notable EMT characteristics, highlighting recent insights and the impact of TAMs on cancer progression. Finally, the review concludes with a discussion of potential therapeutic targets and strategies aimed at mitigating TAM infiltration and disrupting the EMT signaling network, thereby underscoring the potential of emerging treatments to combat TAM-mediated EMT in cancer. This comprehensive analysis reaffirms the necessity for continued exploration into TAMs' regulatory roles within cancer biology to refine therapeutic approaches and improve patient outcomes.

Lipid-associated macrophages for osimertinib resistance and leptomeningeal metastases in NSCLC

Leptomeningeal metastases (LMs) remain a devastating complication of non-small cell lung cancer (NSCLC), particularly following osimertinib resistance. We conducted single-cell RNA sequencing on cerebrospinal fluid (CSF) from EGFR-mutant NSCLC with central nervous system metastases. We found that macrophages of LMs displayed functional and phenotypic heterogeneity and enhanced immunosuppressive properties. A population of lipid-associated macrophages, namely RNASE1_M, were linked to osimertinib resistance and LM development, which was regulated by Midkine (MDK) from malignant epithelial cells. MDK exhibited significant elevation in both CSF and plasma among patients with LMs, with higher MDK levels correlating to poorer outcomes in an independent cohort. Moreover, MDK could promote macrophage M2 polarization with lipid metabolism and phagocytic function. Furthermore, malignant epithelial cells in CSF, particularly after resistance to osimertinib, potentially achieved immune evasion through CD47-SIRPA interactions with RNASE1_M. In conclusion, we revealed a specific subtype of macrophages linked to osimertinib resistance and LM development, providing a potential target to overcome LMs.

The complex interplay of tumor-infiltrating cells in driving therapeutic resistance pathways

Drug resistance remains a significant challenge in cancer treatment. Recently, the interactions among various cell types within the tumor microenvironment (TME) have deepened our understanding of the mechanisms behind treatment resistance. Therefore, this review aims to synthesize current research focusing on infiltrating cells and drug resistance suggesting that targeting the TME could be a viable strategy to combat this issue. Numerous factors, including inflammation, metabolism, senescence, hypoxia, and angiogenesis, contribute to drug resistance could be a viable strategy to combat this issue. Overexpression of STAT3 is commonly associated with drug-resistant cancer cells or stromal cells. Current research often generalizes the impact of stromal cells on resistance, lacking specificity and statistical robustness. Thus, future research should take notice of this issue and aim to provide high-quality evidence. Despite the existing limitations, targeting the TME to overcome therapy resistance hold promising and valuable potential.

Therapeutic advances of targeting receptor tyrosine kinases in cancer

Receptor tyrosine kinases (RTKs), a category of transmembrane receptors, have gained significant clinical attention in oncology due to their central role in cancer pathogenesis. Genetic alterations, including mutations, amplifications, and overexpression of certain RTKs, are critical in creating environments conducive to tumor development. Following their discovery, extensive research has revealed how RTK dysregulation contributes to oncogenesis, with many cancer subtypes showing dependency on aberrant RTK signaling for their proliferation, survival and progression. These findings paved the way for targeted therapies that aim to inhibit crucial biological pathways in cancer. As a result, RTKs have emerged as primary targets in anticancer therapeutic development. Over the past two decades, this has led to the synthesis and clinical validation of numerous small molecule tyrosine kinase inhibitors (TKIs), now effectively utilized in treating various cancer types. In this manuscript we aim to provide a comprehensive understanding of the RTKs in the context of cancer. We explored the various alterations and overexpression of specific receptors across different malignancies, with special attention dedicated to the examination of current RTK inhibitors, highlighting their role as potential targeted therapies. By integrating the latest research findings and clinical evidence, we seek to elucidate the pivotal role of RTKs in cancer biology and the therapeutic efficacy of RTK inhibition with promising treatment outcomes.

CD47-mediated immune evasion in early-stage lung cancer progression

Alveolar and interstitial macrophages play crucial roles in eradicating pathogens and transformed cells in the lungs. The immune checkpoint CD47, found on normal and malignant cells, interacts with the SIRPα ligand on macrophages, inhibiting phagocytosis, antigen presentation, and promoting immune evasion. In this study, we demonstrated that CD47 is not only a transmembrane protein, but that it is also highly concentrated in extracellular vesicles from lung cancer cell lines and patient plasma. Abundant CD47 was observed in the cytoplasm of lung cancer cells, aligning with our finding that it was packed into extracellular vesicles for physiological and pathological functions. In our clinical cohort, extracellular vesicle CD47 was significantly higher in the patients with early-stage lung cancer, emphasizing innate immunity inactivation in early tumor progression. To validate our hypothesis, we established an orthotopic xenograft model mimicking lung cancer development, which showed increased serum soluble CD47 and elevated IL-10/TNF-α ratio, indicating an immune-suppressive tumor microenvironment. CD47 expression led to reduced tumor-infiltrating macrophages during progression, while there was a post-xenograft increase in tumor-associated macrophages. In conclusion, CD47 is pivotal in early lung cancer progression, with soluble CD47 emerging as a key pathological effector.

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

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

LILRB2 inhibition enhances radiation sensitivity in non-small cell lung cancer by attenuating radiation-induced senescence

Radiotherapy (RT) in non-small cell lung cancer (NSCLC) triggers cellular senescence, complicating tumor microenvironments and affecting treatment outcomes. This study examines the role of lymphocyte immunoglobulin-like receptor B2 (LILRB2) in modulating RT-induced senescence and radiosensitivity in NSCLC. Through methodologies including irradiation, lentivirus transfection, and various molecular assays, we assessed LILRB2's expression and its impact on cellular senescence levels and tumor cell behaviors. Our findings reveal that RT upregulates LILRB2, facilitating senescence and a senescence-associated secretory phenotype (SASP), which in turn enhances tumor proliferation and resistance to radiation. Importantly, LILRB2 silencing attenuates these effects by inhibiting the JAK2/STAT3 pathway, significantly increasing radiosensitivity in NSCLC models. Clinical data correlate high LILRB2 expression with reduced RT response and poorer prognosis, suggesting LILRB2's pivotal role in RT-induced senescence and its potential as a therapeutic target to improve NSCLC radiosensitivity.

Targeting STAT3 potentiates CDK4/6 inhibitors therapy in head and neck squamous cell carcinoma

Anti-CDK4/6 therapy has been employed for the treatment for head and neck squamous cell carcinoma (HNSCC) with CDK4/6 hyperactivation, but the response rate is relatively low. In this study, we first showed that CDK4 and CDK6 was over-expressed and conferred poor prognosis in HNSCC. Moreover, in RB-positive HNSCC, STAT3 signaling was activated induced by CDK4/6 inhibition and STAT3 promotes RB deficiency by upregulation of MYC. Thirdly, the combination of Stattic and CDK4/6 inhibitor results in striking anti-tumor effect in vitro and in Cal27 derived animal models. Additionally, phospho-STAT3 level negatively correlates with RB expression and predicts poor prognosis in patients with HNSCC. Taken together, our findings suggest an unrecognized function of STAT3 confers to CDK4/6 inhibitors resistance and presenting a promising combination strategy for patients with HNSCC.

Understanding the dynamics of TKI-induced changes in the tumor immune microenvironment for improved therapeutic effect

BACKGROUND

The dynamic interplay between tyrosine kinase inhibitors (TKIs) and the tumor immune microenvironment (TME) plays a crucial role in the therapeutic trajectory of non-small cell lung cancer (NSCLC). Understanding the functional dynamics and resistance mechanisms of TKIs is essential for advancing the treatment of NSCLC.

METHODS

This study assessed the effects of short-term and long-term TKI treatments on the TME in NSCLC, particularly targeting epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) mutations. We analyzed changes in immune cell composition, cytokine profiles, and key proteins involved in immune evasion, such as laminin subunit γ-2 (LAMC2). We also explored the use of aspirin as an adjunct therapy to modulate the TME and counteract TKI resistance.

RESULTS

Short-term TKI treatment enhanced T cell-mediated tumor clearance, reduced immunosuppressive M2 macrophage infiltration, and downregulated LAMC2 expression. Conversely, long-term TKI treatment fostered an immunosuppressive TME, contributing to drug resistance and promoting immune escape. Differential responses were observed among various oncogenic mutations, with ALK-targeted therapies eliciting a stronger antitumor immune response compared with EGFR-targeted therapies. Notably, we found that aspirin has potential in overcoming TKI resistance by modulating the TME and enhancing T cell-mediated tumor clearance.

CONCLUSIONS

These findings offer new insights into the dynamics of TKI-induced changes in the TME, improving our understanding of NSCLC challenges. The study underscores the critical role of the TME in TKI resistance and suggests that adjunct therapies, like aspirin, may provide new strategies to enhance TKI efficacy and overcome resistance.

The Biological Role of Macrophage in Lung and Its Implications in Lung Cancer Immunotherapy

The lungs are the largest surface of the body and the most important organ in the respiratory system, which are constantly exposed to the external environment. Tissue Resident Macrophages in lung constitutes the important defense against external pathogens. Macrophages connects the innate and adaptive immune system, and also plays important roles in carcinogenesis and cancer immunotherapy. Lung cancer is the leading cause of cancer-related death worldwide, with an overall five-year survival rate of only 21%. Macrophages that infiltrate or aggregate in lung tumor microenvironment are defined as tumor-associated macrophages (TAMs). TAMs are the main components of immune cells in the lung tumor microenvironment. The differentiation and maturation process of TAMs can be roughly divided into two different types: classical activation pathway produces M1 tumor-associated macrophages, and bypass activation pathway produces M2 tumor-associated macrophages. Studies have found that TAMs are related to tumor invasion, metastasis, and treatment resistance, and show potential as a new target for tumor immunotherapy. Therefore, the biological function of macrophages in lung and the role of TAMs in the occurrence, development, and treatment of lung cancer are discussed in this paper.

Tumor-associated macrophages in non-small-cell lung cancer: From treatment resistance mechanisms to therapeutic targets

Non-small cell lung cancer (NSCLC) remains one of the leading causes of cancer-related deaths worldwide. Different treatment approaches are typically employed based on the stage of NSCLC. Common clinical treatment methods include surgical resection, drug therapy, and radiation therapy. However, with the introduction and utilization of immune checkpoint inhibitors, cancer treatment has entered a new era, completely revolutionizing the treatment landscape for various cancers and significantly improving overall patient survival. Concurrently, treatment resistance often poses a critical challenge, with many patients experiencing disease progression following an initial response due to treatment resistance. Increasing evidence suggests that the tumor microenvironment (TME) plays a pivotal role in treatment resistance. Tumor-associated macrophages (TAMs) within the TME can promote treatment resistance in NSCLC by secreting various cytokines activating signaling pathways, and interacting with other immune cells. Therefore, this article will focus on elucidating the key mechanisms of TAMs in treatment resistance and analyze how targeting TAMs can reduce the levels of treatment resistance in NSCLC, providing a comprehensive understanding of the principles and approaches to overcome treatment resistance in NSCLC.

Targeting HDAC6 improves anti-CD47 immunotherapy

BACKGROUND

Cancer cells can overexpress CD47, an innate immune checkpoint that prevents phagocytosis upon interaction with signal regulatory protein alpha (SIRPα) expressed in macrophages and other myeloid cells. Several clinical trials have reported that CD47 blockade reduces tumor growth in hematological malignancies. However, CD47 blockade has shown modest results in solid tumors, including melanoma. Our group has demonstrated that histone deacetylase 6 inhibitors (HDAC6is) have immunomodulatory properties, such as controlling macrophage phenotype and inflammatory properties. However, the molecular and cellular mechanisms controlling these processes are not fully understood. In this study, we evaluated the role of HDAC6 in regulating the CD47/SIRPα axis and phagocytosis in macrophages.

METHODS

We tested the role of HDAC6is, especially Nexturastat A, in regulating macrophage phenotype and phagocytic function using bone marrow-derived macrophages and macrophage cell lines. The modulation of the CD47/SIRPα axis and phagocytosis by HDAC6is was investigated using murine and human melanoma cell lines and macrophages. Phagocytosis was evaluated via coculture assays of macrophages and melanoma cells by flow cytometry and immunofluorescence. Lastly, to evaluate the antitumor activity of Nexturastat A in combination with anti-CD47 or anti-SIRPα antibodies, we performed in vivo studies using the SM1 and/or B16F10 melanoma mouse models.

RESULTS

We observed that HDAC6is enhanced the phenotype of antitumoral M1 macrophages while decreasing the protumoral M2 phenotype. In addition, HDAC6 inhibition diminished the expression of SIRPα, increased the expression of other pro-phagocytic signals in macrophages, and downregulated CD47 expression in mouse and human melanoma cells. This regulatory role on the CD47/SIRPα axis translated into enhanced antitumoral phagocytic capacity of macrophages treated with Nexturastat A and anti-CD47. We also observed that the systemic administration of HDAC6i enhanced the in vivo antitumor activity of anti-CD47 blockade in melanoma by modulating macrophage and natural killer cells in the tumor microenvironment. However, Nexturastat A did not enhance the antitumor activity of anti-SIRPα despite its modulation of macrophage populations in the SM1 tumor microenvironment.

CONCLUSIONS

Our results demonstrate the critical regulatory role of HDAC6 in phagocytosis and innate immunity for the first time, further underscoring the use of these inhibitors to potentiate CD47 immune checkpoint blockade therapeutic strategies.

The cross-talk between macrophages and tumor cells as a target for cancer treatment

Macrophages represent an important component of the innate immune system. Under physiological conditions, macrophages, which are essential phagocytes, maintain a proinflammatory response and repair damaged tissue. However, these processes are often impaired upon tumorigenesis, in which tumor-associated macrophages (TAMs) protect and support the growth, proliferation, and invasion of tumor cells and promote suppression of antitumor immunity. TAM abundance is closely associated with poor outcome of cancer, with impediment of chemotherapy effectiveness and ultimately a dismal therapy response and inferior overall survival. Thus, cross-talk between cancer cells and TAMs is an important target for immune checkpoint therapies and metabolic interventions, spurring interest in it as a therapeutic vulnerability for both hematological cancers and solid tumors. Furthermore, targeting of this cross-talk has emerged as a promising strategy for cancer treatment with the antibody against CD47 protein, a critical macrophage checkpoint recognized as the "don't eat me" signal, as well as other metabolism-focused strategies. Therapies targeting CD47 constitute an important milestone in the advancement of anticancer research and have had promising effects on not only phagocytosis activation but also innate and adaptive immune system activation, effectively counteracting tumor cells' evasion of therapy as shown in the context of myeloid cancers. Targeting of CD47 signaling is only one of several possibilities to reverse the immunosuppressive and tumor-protective tumor environment with the aim of enhancing the antitumor response. Several preclinical studies identified signaling pathways that regulate the recruitment, polarization, or metabolism of TAMs. In this review, we summarize the current understanding of the role of macrophages in cancer progression and the mechanisms by which they communicate with tumor cells. Additionally, we dissect various therapeutic strategies developed to target macrophage-tumor cell cross-talk, including modulation of macrophage polarization, blockade of signaling pathways, and disruption of physical interactions between leukemia cells and macrophages. Finally, we highlight the challenges associated with tumor hypoxia and acidosis as barriers to effective cancer therapy and discuss opportunities for future research in this field.

Targeting tumor-associated macrophage: an adjuvant strategy for lung cancer therapy

The emergence of immunotherapy has revolutionized the treatment landscape for various types of cancer. Nevertheless, lung cancer remains one of the leading causes of cancer-related mortality worldwide due to the development of resistance in most patients. As one of the most abundant groups of immune cells in the tumor microenvironment (TME), tumor-associated macrophages (TAMs) play crucial and complex roles in the development of lung cancer, including the regulation of immunosuppressive TME remodeling, metabolic reprogramming, neoangiogenesis, metastasis, and promotion of tumoral neurogenesis. Hence, relevant strategies for lung cancer therapy, such as inhibition of macrophage recruitment, TAM reprograming, depletion of TAMs, and engineering of TAMs for drug delivery, have been developed. Based on the satisfactory treatment effect of TAM-targeted therapy, recent studies also investigated its synergistic effect with current therapies for lung cancer, including immunotherapy, radiotherapy, chemotherapy, anti-epidermal growth factor receptor (anti-EGFR) treatment, or photodynamic therapy. Thus, in this article, we summarized the key mechanisms of TAMs contributing to lung cancer progression and elaborated on the novel therapeutic strategies against TAMs. We also discussed the therapeutic potential of TAM targeting as adjuvant therapy in the current treatment of lung cancer, particularly highlighting the TAM-centered strategies for improving the efficacy of anti-programmed cell death-1/programmed cell death-ligand 1 (anti-PD-1/PD-L1) treatment.

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.

Targeting the STAT3 oncogenic pathway: Cancer immunotherapy and drug repurposing

Immune effector cells in the microenvironment tend to be depleted or remodeled, unable to perform normal functions, and even promote the malignant characterization of tumors, resulting in the formation of immunosuppressive microenvironments. The strategy of reversing immunosuppressive microenvironment has been widely used to enhance the tumor immunotherapy effect. Signal transducer and activator of transcription 3 (STAT3) was found to be a crucial regulator of immunosuppressive microenvironment formation and activation as well as a factor, stimulating tumor cell proliferation, survival, invasiveness and metastasis. Therefore, regulating the immune microenvironment by targeting the STAT3 oncogenic pathway might be a new cancer therapy strategy. This review discusses the pleiotropic effects of STAT3 on immune cell populations that are critical for tumorigenesis, and introduces the novel strategies targeting STAT3 oncogenic pathway for cancer immunotherapy. Lastly, we summarize the conventional drugs used in new STAT3-targeting anti-tumor applications.

CD47: The Next Frontier in Immune Checkpoint Blockade for Non-Small Cell Lung Cancer

The success of PD-1/PD-L1-targeted therapy in lung cancer has resulted in great enthusiasm for additional immunotherapies in development to elicit similar survival benefits, particularly in patients who do not respond to or are ineligible for PD-1 blockade. CD47 is an immunosuppressive molecule that binds SIRPα on antigen-presenting cells to regulate an innate immune checkpoint that blocks phagocytosis and subsequent activation of adaptive tumor immunity. In lung cancer, CD47 expression is associated with poor survival and tumors with EGFR mutations, which do not typically respond to PD-1 blockade. Given its prognostic relevance, its role in facilitating immune escape, and the number of agents currently in clinical development, CD47 blockade represents a promising next-generation immunotherapy for lung cancer. In this review, we briefly summarize how tumors disrupt the cancer immunity cycle to facilitate immune evasion and their exploitation of immune checkpoints like the CD47-SIRPα axis. We also discuss approved immune checkpoint inhibitors and strategies for targeting CD47 that are currently being investigated. Finally, we review the literature supporting CD47 as a promising immunotherapeutic target in lung cancer and offer our perspective on key obstacles that must be overcome to establish CD47 blockade as the next standard of care for lung cancer therapy.

Tumor-associated macrophages mediate resistance of EGFR-TKIs in non-small cell lung cancer: mechanisms and prospects

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are the first-line standard treatment for advanced non-small cell lung cancer (NSCLC) with EGFR mutation. However, resistance to EGFR-TKIs is inevitable. Currently, most studies on the mechanism of EGFR-TKIs resistance mainly focus on the spontaneous resistance phenotype of NSCLC cells. Studies have shown that the tumor microenvironment (TME) also mediates EGFR-TKIs resistance in NSCLC. Tumor-associated macrophages (TAMs), one of the central immune cells in the TME of NSCLC, play an essential role in mediating EGFR-TKIs resistance. This study aims to comprehensively review the current mechanisms underlying TAM-mediated resistance to EGFR-TKIs and discuss the potential efficacy of combining EGFR-TKIs with targeted TAMs therapy. Combining EGFR-TKIs with TAMs targeting may improve the prognosis of NSCLC with EGFR mutation to some extent.

Exosomal non-coding RNAs-mediated EGFR-TKIs resistance in NSCLC with EGFR mutation

Lung cancer is the leading cause of cancer-related mortality worldwide. The advent of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) has significantly improved survival rates of patients with EGFR-mutant non-small cell lung cancer (NSCLC). However, as with other antitumor drugs, resistance to EGFR-TKIs is inevitably develops over time. Exosomes, extracellular vesicles with a 30-150 nm diameter, have emerged as vital mediators of intercellular communication. Recent studies revealed that exosomes carry non-coding RNAs (ncRNAs), including circular RNA (circRNA), microRNA (miRNA), and long noncoding RNA (lncRNA), which contribute to the development of EGFR-TKIs resistance. This review provides a comprehensive overview of the current research on exosomal ncRNAs mediating EGFR-TKIs resistance in EGFR-mutated NSCLC. In the future, detecting exosome ncRNAs can be used to monitor targeted therapy for NSCLC. Meanwhile, developing therapeutic regimens targeting these resistance mechanisms may provide additional clinical benefits to patients with EGFR-mutated NSCLC.