Tumor-associated fibrosis impairs immune surveillance and response to immune checkpoint blockade in non-small cell lung cancer

Overcoming the novel glycan-lectin checkpoints in tumor microenvironments for the success of the cross-presentation-based immunotherapy

In pursuit of meeting the ever-rising demand for cancer therapies, cross-presentation-based glyconanovaccines (GNVs) targeting C-type lectin receptors (CLRs) on DCs have shown significant potential as cutting-edge cancer immunotherapy. GNVs are an attractive approach to induce anti-cancer cytotoxic T lymphocyte responses. Despite immune checkpoints (ICs) being well established and an obstacle to the success of GNVs, glycan-lectin circuits are emerging as unique checkpoints due to their immunomodulatory functions. Given the role of aberrant tumor glycosylation in promoting immune evasion, mitigating these effects is crucial for the efficacy of GNVs. Lectins, such as siglecs and galectins, are detrimental to the tumor immune landscape as they promote an immunosuppressive TME. From this perspective, this review aims to explore glycan-lectin ICs and their influence on the efficacy of GNVs. We aim to discuss various ICs in the TME followed by drawbacks of immune checkpoint inhibitors (ICIs). We will also emphasize the altered glycosylation profile of tumors, addressing their immunosuppressive nature along with ways in which CLRs, siglecs, and galectins contribute to immune evasion and cancer progression. Considering the resistance towards ICIs, current and prospective approaches for targeting glycan-lectin circuits and future prospects of these endeavors in harnessing the full potential of GNVs will also be highlighted.

Resistance to PD-1/PD-L1 immune checkpoint blockade in advanced non-small cell lung cancer

Lung cancer is one of the most common malignant tumors, of which non-small cell lung cancer (NSCLC) accounts for about 85 %. Although immune checkpoint inhibitors (ICIs), particularly PD-1/PD-L1 inhibitors, have significantly improved the prognosis of patients with NSCLC. There are still many patients do not benefit from ICIs. Primary resistance remains a major challenge in advanced NSCLC. The cancer-immunity cycle describes the process from antigen release to T cell recognition and killing of the tumor, which provides a framework for understanding anti-tumor immunity. The classical cycle consists of seven steps, and alterations at each stage can result in resistance. This review examines the current status of PD-1/PD-L1 blockade in the treatment of advanced NSCLC and explores potential mechanisms of resistance. We summarize the latest clinical trials of PD-1/PD-L1 inhibitors combined with other therapies and explore potential targets for overcoming primary resistance to PD-1/PD-L1 inhibitors.

Translational Selenium Nanoparticles Promotes Clinical Non-small-cell Lung Cancer Chemotherapy via Activating Selenoprotein-driven Immune Manipulation

Reconstructing the tumor immune microenvironment is an effective strategy to enhance therapeutic efficacy limited by immunosuppression in non-small-cell lung cancer (NSCLC). In this study, it is found that selenium (Se) depletion and immune dysfunction are present in patients with advanced NSCLC compared with healthy volunteers. Surprisingly, Se deficiency resulted in decreased immunity and accelerated rapid tumor growth in the mice model, which further reveals that the correlation between micronutrient Se and lung cancer progression. This pioneering work achieves 500-L scale production of Se nanoparticles (SeNPs) at GMP level and utilizes it to reveal how and why the trace element Se can enhance clinical immune-mediated treatment efficacy against NSCLC. The results found that translational SeNPs can promote the proliferation of NK cells and enhance its cytotoxicity against cancer cells by activating mTOR signaling pathway driven by GPXs to regulate the secretion of cytokines to achieve an antitumor response. Moreover, a clinical study of an Investigator-initiated Trial shows that translational SeNPs supplementation in combination with bevacizumab/cisplatin/pemetrexed exhibits enhanced therapeutic efficacy with an objective response rate of 83.3% and a disease control rate of 100%, through potentiating selenoprotein-driven antitumor immunity. Taken together, this study, for the first time, highlights the translational SeNPs-enhanced therapeutic efficacy against clinical advanced NSCLC.

Spatial Regulation of Cancer-Associated Fibroblasts and Tumor Cells via pH-Responsive Bispecific Antibody Delivery for Enhanced Chemo-Immunotherapy Synergy

The effectiveness of chemotherapy is often compromised by physiological barriers and an immunosuppressive tumor microenvironment. Cancer-associated fibroblasts (CAFs) significantly contribute to the reconfiguration of the tumor extracellular matrix (ECM) and the suppression of immune responses, making them crucial targets for therapeutic intervention. Here, a tumor acidic microenvironment-responsive delivery system that utilizes tumor cell-derived microparticles (MPs) as carriers for the chemotherapeutic agent doxorubicin (DOX) and the bispecific antibody YM101 targeting both TGF-β and PD-L1 is developed (DOX@MPs-YM101) to spatially regulate both CAFs and tumor cells for enhanced chemotherapeutic efficacy. DOX@MPs-YM101 efficiently targets tumor tissues and releases DOX@MPs and YM101 in response to the acidic tumor microenvironment. YM101 reprograms CAFs and reduces the tumor ECM, facilitating tumor accumulation and deep penetration of DOX@MPs-YM101. DOX@MPs are highly internalized into tumor cells, triggering immunogenic cell death (ICD) and activating CD8+ T cell-mediated antitumor immunity. The reprogramming of CAFs by YM101 further promotes the accumulation of CD8+ T cells and reduces the number of immunosuppressive cells within the tumors. Additionally, YM101 effectively neutralizes PD-L1 on tumor cells induced by DOX@MPs, restoring CD8+ T cell activity and generating long-term antitumor immune memory to prevent tumor recurrence. Our findings highlight the potential of DOX@MPs-YM101 to improve chemotherapy in cancer treatment.

The role of TIGIT-CD226-PVR axis in mediating T cell exhaustion and apoptosis in NSCLC

The treatment of non-small cell lung cancer (NSCLC) remains a critical challenge in oncology, primarily due to the dysfunction and exhaustion of T cells within the tumor microenvironment, which greatly limits the effectiveness of immunotherapy. This study investigates the regulatory role of the T cell immunoglobulin and ITIM domain (TIGIT)-CD226-PVR signaling axis in the exhaustion and apoptosis of cluster of differentiation (CD)27+/CD127+T cells in NSCLC. Utilizing single-cell sequencing technology, we conducted a comprehensive gene expression analysis of T cells in a mouse model of NSCLC. Bioinformatics analysis revealed that the TIGIT-CD226-PVR signaling axis is highly active in the CD27+/CD127+T cell subset and is closely associated with their functional decline and exhaustion. In vitro experiments further demonstrated that inhibiting the TIGIT-PVR pathway while activating the CD226-PVR pathway significantly restored T cell proliferation and effector function. Importantly, in vivo studies showed that targeting this axis can significantly alleviate T cell exhaustion, enhance their cytotoxicity against NSCLC cells, and promote apoptosis, thereby improving the efficacy of immunotherapy.

Tissue-specific properties of type 1 dendritic cells in lung cancer: implications for immunotherapy

Checkpoint inhibitors have led to remarkable benefits in non-small cell lung cancer (NSCLC), yet response rates remain below expectations. High-dimensional analysis and mechanistic experiments in clinical samples and relevant NSCLC models uncovered the immune composition of lung cancer tissues, providing invaluable insights into the functional properties of tumor-infiltrating T cells and myeloid cells. Among myeloid cells, type 1 conventional dendritic cells (cDC1s) stand out for their unique ability to induce effector CD8 T cells against neoantigens and coordinate antitumoral immunity. Notably, lung resident cDC1 are particularly abundant and long-lived and express a unique tissue-specific gene program, underscoring their central role in lung immunity. Here, we discuss recent insights on the induction and regulation of antitumoral T cell responses in lung cancer, separating it from the tissue-agnostic knowledge generated from heterogeneous tumor models. We focus on the most recent studies dissecting functional states and spatial distribution of lung cDC1 across tumor stages and their impact on T cell responses to neoantigens. Finally, we highlight relevant gaps and emerging strategies to harness lung cDC1 immunostimulatory potential.

Primary and Acquired Resistance to Immunotherapy with Checkpoint Inhibitors in NSCLC: From Bedside to Bench and Back

Immunotherapy with checkpoint inhibitors has become the cornerstone of systemic treatment for non-oncogene addicted non-small-cell lung cancer. Despite its pivotal role, a significant proportion of patients-approximately 70-85%-either exhibit primary resistance to PD-1 blockade or develop acquired resistance following an initial benefit, even in combination with chemotherapy and/or anti-CTLA-4 agents. The phenomenon of primary and acquired resistance to immunotherapy represents a critical clinical challenge, largely based on our incomplete understanding of the mechanisms of action of immunotherapy, and the resulting lack of accurate predictive biomarkers. Here, we review the definitions and explore the proposed mechanisms of primary and acquired resistance, including those related to the tumor microenvironment, systemic factors, and intrinsic tumor characteristics. We also discuss translational data on adaptive changes within tumor cells and the immune infiltrate following exposure to checkpoint inhibitors. Lastly, we offer a comprehensive overview of current and emerging therapeutic strategies designed to prevent primary resistance and counteract acquired resistance.

The multi-faceted immune modulatory role of S100A4 in cancer and chronic inflammatory disease

S100A4 is a Ca2+-binding protein involved in multiple chronic inflammatory and neoplastic conditions. This review focuses on recent advances in the understanding of S100A4 function in immune cells, comparing and contrasting S100A4 regulation of immune responses in cancer and chronic inflammatory diseases. We provide evidence that S100A4 regulation of immune cell function has a profound role in promoting the pathogenesis of cancer and pro-inflammatory conditions. Finally, we discuss relevant future directions to target S100A4 therapeutically in different disease states.

Development of delayed pulmonary toxicities and transcriptional changes in pre-existing interstitial lung disease mice after partial thoracic irradiation

BACKGROUND

Lung cancer patients with comorbid interstitial lung disease (LC-ILD) have an increased risk of developing severe or even fatal radiation pneumonitis after thoracic radiotherapy. However, the underlying mechanisms of its pathogenesis are still inconclusive. No approved biomarker or medicine is available to prevent pulmonary toxicities in LC-ILD patients. Appropriate management for them remains a challenge for clinicians due to treatment-related complications.

METHODS

To elucidate the histopathological characteristics and molecular mechanisms responsible for this severe toxicity in vivo, C57BL/6J mice were used to develop different lung injury models, including radiation-induced lung injury (RILI), bleomycin-induced pulmonary fibrosis (BIPF), and severe radiation-related lung injury (sRRLI) murine model. Biopsy examination was performed on hematoxylin and eosin (H&E), Masson's trichrome, and immunohistochemistry-stained lung tissue sections. Changes in lung function were measured. RNA extracted from mouse lung tissues was sequenced on the Illumina Novaseq platform.

RESULTS

A severe lung injury model after irradiation was built based on pre-existing ILD mice induced by BLM administration. Enhanced lung injury was observed in the sRRLI model, including higher mortality and pulmonary function loss within six months compared to the mono-treatment groups. Autopsy revealed that bilateral diffuse alveolar damage (DAD) with an overlap of exudative, proliferative, and fibrosing patterns was usually presented in the sRRLI model. The histological phenotypes manifested exudative predominated DAD phase in the early phase and proliferating DAD pattern in the late phase. Bioinformatic analysis showed signaling pathways relevant to immune cell migration, epithelial cell development, and extracellular structure organization were commonly activated in different models. Furthermore, the involvement of epithelial cells and the infiltration of macrophages and CD4 + lymphocytes were validated during extensive lung remodeling in the sRRLI group.

CONCLUSIONS

Delayed effects of significantly declined lung function and high mortality were observed in the sRRLI model. DAD with progressive inflammation and fibrosis in bilateral lungs contributed to severe or even fatal complications after partial thoracic irradiation. The hyperactivation of inflammatory responses was clarified during long-term pulmonary toxicities. More studies are needed to investigate potential strategies to prevent and rescue severe lung complications.

Role of CALCR expression in liver cancer: Implications for the immunotherapy response

Liver hepatocellular carcinoma (LIHC) is a prevalent and lethal malignancy with a complex molecular landscape. Fibrosis and ferroptosis are implicated in LIHC progression, yet their roles remain to be elucidated. The present study investigated the expression and prognostic significance of calcitonin receptor (CALCR), a gene that intersects the pathways of fibrosis and ferroptosis, across LIHC and other types of cancer. Data were obtained from The Cancer Genome Atlas and the Molecular Signatures Database. LIHC patients were classified into two clusters based on fibrosis‑related gene expression using ConsensusClusterPlus. Single‑sample gene set enrichment analysis was employed to quantify fibrosis and ferroptosis levels. Correlation, survival and nomogram analyses were performed to assess the prognostic value of CALCR. Additionally, single‑cell RNA sequencing data from the Tumor Immune Single Cell Hub 2 (TISCH2) and pan‑cancer analyses of genomic heterogeneity features were incorporated. The present study also identified a putative regulatory role for CALCR in LIHC cell migration, proliferation and apoptosis. CALCR was identified as a significant prognostic marker for LIHC. Patients with high CALCR expression exhibited shortened overall survival (OS) and disease‑specific survival (DSS). Specifically, the hazard ratios (HRs) for OS and DSS were 1.76 [95% confidence interval (CI): 1.23=2.49) and 1.77 (95% CI: 1.13=2.78], respectively, with corresponding P‑values of 0.002 for OS and 0.013 for DSS. Analyses of immune cell infiltration revealed a more complex immune environment in patients with low CALCR expression, suggesting differential responses to immunotherapy. Furthermore, in HepG‑2 and HuH‑7 cells, small interfering (si)‑CALCR increased apoptosis while reducing proliferation and migration compared with si‑negative control. CALCR serves as a significant prognostic biomarker for LIHC, influencing both molecular pathways and the immune landscape. Its expression is associated with improved survival outcomes and distinct genomic features, positioning it as a potential therapeutic target and predictor of immunotherapy efficacy.

KRASG12D drives immunosuppression in lung adenocarcinoma through paracrine signaling

Lung cancer is the leading cause of cancer deaths in the United States. New targeted therapies against the once-deemed undruggable oncogenic KRAS are changing current therapeutic paradigms. However, resistance to targeted KRAS inhibitors almost inevitably occurs; resistance can be driven by tumor cell-intrinsic changes or by changes in the microenvironment. Here, we utilized a genetically engineered mouse model of KRASG12D-driven lung cancer that allows for inducible and reversible expression of the oncogene: activation of oncogenic KRASG12D induces tumor growth; conversely, inactivation of KRASG12D causes tumor regression. We showed that in addition to regulating cancer cell growth and survival, oncogenic KRAS regulated the transcriptional status of cancer-associated fibroblasts and macrophages in this model. Utilizing ex vivo approaches, we showed that secreted factors from cancer cells induced the expression of multiple cytokines in lung fibroblasts, and in turn drove expression of immunosuppressive factors, such as arginase 1, in macrophages. In summary, fibroblasts emerged as a key source of immune regulatory signals, and a potential therapeutic target for improving the efficacy of KRAS inhibitors in lung cancer.

The impact of POSTN on tumor cell behavior and the tumor microenvironment in lung adenocarcinoma

BACKGROUND

The role of cancer-associated fibroblasts (CAFs) in modulating the anti-tumor immune response in lung adenocarcinoma (LUAD) remains elusive, primarily due to the heterogeneous nature of these cells. This heterogeneity muddles the understanding of their impact on immunotherapy effectiveness.

METHODS

We utilized the LUAD single-cell dataset to precisely classify tumor cells and CAFs. By employing CSOmap, we predicted cell interactions and reconstructed the three-dimensional spatial organization, highlighting the close association of myofibroblasts with specific tumor cell subsets. A prognostic signature based on myofibroblast-specific genes was developed and validated to predict LUAD patient survival. In vivo, we conducted subcutaneous tumorigenesis assays in mice, treating with PD-L1 and the POSTN inhibitor RGD to assess the combined effects of POSTN pathway blockade and immunotherapy on tumor growth and immune cell dynamics. For analyzing the tumor microenvironment, we used flow cytometry and multiplex immunofluorescence staining. In vitro, with cell lines like A549, H1299, and RAW264.7, we investigated POSTN's role in macrophage recruitment and polarization. Through ELISA, Western blot, and immunofluorescence staining, we explored how POSTN acts via ITGB3, providing a more comprehensive understanding of its mechanism in LUAD.

RESULTS

Our analysis discerned six distinct tumor cell subsets, with cluster 1 displaying pronounced cellular communication with myofibroblasts, evidenced by spatial accessibility in three dimensions. The myofibroblast-specific genomic signature was established and confirmed as a robust, independent prognostic indicator. Among the signature genes, CTHRC1, POSTN, and MMP11 emerged as high-variant genes in myofibroblasts, identified via the FindAllMarkers function in Seurat. Of these, only POSTN's differential expression correlated with LUAD prognosis, with high POSTN expression being indicative of poor patient outcomes. In vitro, recombinant POSTN was observed to enhance tumor invasiveness, motility, and proliferation, while attenuating apoptosis and fostering an EMT phenotype. Additionally, Transwell assays showed that rPOSTN could induce macrophage infiltration via ITGB3 and drive M2 polarization via the PI3K-Akt-JNK pathway. Importantly, blocking the POSTN pathway augmented the efficacy of PD-L1 inhibitors. In vivo, in a mouse subcutaneous tumorigenesis model, the combination of POSTN pathway blockade with PD-L1 inhibitor treatment notably inhibited tumor growth and changed the tumor microenvironment's immune cell composition, with an increase in CD8+ T cells and a favorable shift in the M1/M2 macrophage ratio.

CONCLUSION

This study sheds light on the intricate interplay between tumor cells and myofibroblasts in LUAD, pinpointing the pivotal role of the highly mutated gene POSTN. It underscores POSTN's instrumental role in manipulating the tumor microenvironment, primarily by promoting EMT and inhibiting apoptosis in lung cancer cells, alongside enhancing macrophage recruitment and fostering M2 polarization. These insights provide a foundation for enriching immunotherapy strategies, particularly through the inhibition of the POSTN pathway in LUAD.

High levels of fibrotic tumor components are associated with recurrence and intratumoral immune status in advanced colorectal cancer patients

The importance of collagen and elastin remains incompletely understood concerning tumor immunity in cancer tissues. This study explored the clinical significance of collagen and elastin deposition on tumor immunity in advanced colorectal cancer patients. The collagen and elastin contents were assessed simultaneously using elastic van Gieson (EVG) histochemical staining. Immunohistochemical staining was performed to measure the immune cell markers CD3, CD8, CD86, and CD163 in surgically resected primary tumors from 78 pT4 colorectal cancer patients. High collagen, elastin, and EVG scores are associated with aggressive characteristics and short disease-free survival. A high EVG score was identified as an independent predictor of poor disease-free survival. Furthermore, tumors with high collagen and EVG scores exhibited significantly fewer intratumoral CD3 + and CD8 + cells. Evaluating tumor fibrosis using the classical and straightforward EVG staining method could be a reliable predictor of recurrence in high-risk colorectal cancer patients with tumor immune tolerance.

Role of the TME in immune checkpoint blockade resistance of non-small cell lung cancer

Primary and secondary resistance to immune checkpoint blockade (ICB) reduces its efficacy. The mechanisms underlying immunotherapy resistance are highly complex. In non-small cell lung cancer (NSCLC), these mechanisms are primarily associated with the loss of programmed cell death-ligand 1 (PD-L1) expression, genetic mutations, circular RNA axis and transcription factor regulation, antigen presentation disorders, and dysregulation of signaling pathways. Additionally, alterations in the tumor microenvironment (TME) play a pivotal role in driving immunotherapy resistance. Primary resistance is mainly attributed to TME alterations, including mutations and co-mutations, modulation of T cell infiltration, enrichment of M2 tumor-associated macrophages (M2-TAMs) and mucosal-associated invariant T (MAIT) cells, vascular endothelial growth factor (VEGF), and pulmonary fibrosis. Acquired resistance mainly stems from changes in cellular infiltration patterns leading to "cold" or "hot" tumors, altered interferon (IFN) signaling pathway expression, involvement of extracellular vesicles (EVs), and oxidative stress responses, as well as post-treatment gene mutations and circadian rhythm disruption (CRD). This review presents an overview of various mechanisms underlying resistance to ICB, elucidates the alterations in the TME during primary, adaptive, and acquired resistance, and discusses existing strategies for overcoming ICB resistance.

Cellular dynamics of tumor microenvironment driving immunotherapy resistance in non-small-cell lung carcinoma

Immune checkpoint inhibitors (ICIs) have profoundly reshaped the treatment paradigm for non-small cell lung cancer (NSCLC). Despite these advancements, primary and secondary resistance to ICIs remain prevalent challenges in managing advanced NSCLC. Recent studies have highlighted the significant role of the tumor microenvironment (TME) in modulating treatment responses. This review aims to comprehensively examine the interactive roles of immune/stromal cells-such as T cells, B cells, neutrophils, macrophages, and CAFs within the TME, elucidating how these diverse cellular interactions contribute to immunotherapy resistance. It focuses on the dynamic interactions among diverse cell types such as the varying states of T cells under the influence of TME constituents like immune cells and cancer-associated fibroblasts (CAFs). By exploring the mechanisms involved in the complex cellular interactions, we highlight novel therapeutic targets and strategies aimed at overcoming resistance, thereby enhancing the efficacy of ICIs in NSCLC. Our synthesis of recent research provides critical insights into the multifaceted mechanisms of resistance and paves the way for the development of more effective, personalized treatment approaches.

Decoding tumor-fibrosis interplay: mechanisms, impact on progression, and innovative therapeutic strategies

Malignant tumors are a category of diseases that possess invasive and metastatic capabilities, with global incidence and mortality rates remaining high. In recent years, the pivotal role of fibrosis in tumor progression, drug resistance, and immune evasion has increasingly been acknowledged. Fibrosis enhances the proliferation, migration, and invasion of tumor cells by modifying the composition and structure of the extracellular matrix, thereby offering protection for immune evasion by tumor cells. The activation of cancer-associated fibroblasts (CAFs) plays a significant role in this process, as they further exacerbate the malignant traits of tumors by secreting a variety of cytokines and growth factors. Anti-fibrotic tumor treatment strategies, including the use of anti-fibrotic drugs and inhibition of fibrosis-related signaling pathways such as Transforming Growth Factor-β (TGF-β), have demonstrated potential in delaying tumor progression and improving the effectiveness of chemotherapy, targeted therapy, and immunotherapy. In the future, by developing novel drugs that target the fibrotic microenvironment, new therapeutic options may be available for patients with various refractory tumors.

Cancer associated fibroblasts and metabolic reprogramming: unraveling the intricate crosstalk in tumor evolution

Metabolic reprogramming provides tumors with an energy source and biofuel to support their survival in the malignant microenvironment. Extensive research into the intrinsic oncogenic mechanisms of the tumor microenvironment (TME) has established that cancer-associated fibroblast (CAFs) and metabolic reprogramming regulates tumor progression through numerous biological activities, including tumor immunosuppression, chronic inflammation, and ecological niche remodeling. Specifically, immunosuppressive TME formation is promoted and mediators released via CAFs and multiple immune cells that collectively support chronic inflammation, thereby inducing pre-metastatic ecological niche formation, and ultimately driving a vicious cycle of tumor proliferation and metastasis. This review comprehensively explores the process of CAFs and metabolic regulation of the dynamic evolution of tumor-adapted TME, with particular focus on the mechanisms by which CAFs promote the formation of an immunosuppressive microenvironment and support metastasis. Existing findings confirm that multiple components of the TME act cooperatively to accelerate the progression of tumor events. The potential applications and challenges of targeted therapies based on CAFs in the clinical setting are further discussed in the context of advancing research related to CAFs.

Multimodal analysis unveils tumor microenvironment heterogeneity linked to immune activity and evasion

The cellular and molecular heterogeneity of tumors is a major obstacle to cancer immunotherapy. Here, we use a systems biology approach to derive a signature of the main sources of heterogeneity in the tumor microenvironment (TME) from lung cancer transcriptomics. We demonstrate that this signature, which we called iHet, is conserved in different cancers and associated with antitumor immunity. Through analysis of single-cell and spatial transcriptomics data, we trace back the cellular origin of the variability explaining the iHet signature. Finally, we demonstrate that iHet has predictive value for cancer immunotherapy, which can be further improved by disentangling three major determinants of anticancer immune responses: activity of immune cells, immune infiltration or exclusion, and cancer-cell foreignness. This work shows how transcriptomics data can be integrated to derive a holistic representation of the phenotypic heterogeneity of the TME and to predict its unfolding and fate during immunotherapy with immune checkpoint blockers.

CAFs and T cells interplay: The emergence of a new arena in cancer combat

The interaction between the immune system and the tumor matrix has a huge impact on the progression and treatment of cancer. This paper summarizes and discusses the crosstalk between T cells and cancer-associated fibroblasts (CAFs). CAFs can also produce inhibitors that counteract the function of T cells and promote tumor immune escape, while T cells can also engage in complex two-way interactions with CAFs through direct cell contact, the exchange of soluble factors such as cytokines, and the remodeling of the extracellular matrix. Precise targeted intervention can effectively reverse tumor-promoting crosstalk between T cells and CAFs, improve anti-tumor immune response, and provide a new perspective for cancer treatment. Therefore, it is important to deeply understand the mechanism of crosstalk between T cells and CAFs. This review aims to outline the underlying mechanisms of these interactions and discuss potential therapeutic strategies that may become fundamental tools in the treatment of cancer, especially hard-to-cure cancers.

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.

Why Is Wnt/β-Catenin Not Yet Targeted in Routine Cancer Care?

Despite significant progress in cancer prevention, screening, and treatment, the still limited number of therapeutic options is an obstacle towards increasing the cancer cure rate. In recent years, many efforts were put forth to develop therapeutics that selectively target different components of the oncogenic Wnt/β-catenin signaling pathway. These include small molecule inhibitors, antibodies, and more recently, gene-based approaches. Although some of them showed promising outcomes in clinical trials, the Wnt/β-catenin pathway is still not targeted in routine clinical practice for cancer management. As for most anticancer treatments, a critical limitation to the use of Wnt/β-catenin inhibitors is their therapeutic index, i.e., the difficulty of combining effective anticancer activity with acceptable toxicity. Protecting healthy tissues from the effects of Wnt/β-catenin inhibitors is a major issue due to the vital role of the Wnt/β-catenin signaling pathway in adult tissue homeostasis and regeneration. In this review, we provide an up-to-date summary of clinical trials on Wnt/β-catenin pathway inhibitors, examine their anti-tumor activity and associated adverse events, and explore strategies under development to improve the benefit/risk profile of this therapeutic approach.

Potential association between COVID-19 infections and the declining incidence of lung cancers

BACKGROUND

The COVID-19 pandemic has significantly impacted global health and prompted studies on its effects across various diseases. Recent data suggest a potential correlation between COVID-19 and a decrease in lung cancer incidence. This study examines the association between COVID-19 infection and changes in lung cancer cases.

MATERIAL AND METHODS

We conducted a retrospective analysis of medical records from Clinic Lüdenscheid, Germany, from January 1, 2018, to December 31, 2021, comparing lung cancer cases before and during the pandemic. Demographic characteristics and cancer stages were also assessed.

RESULTS

We evaluated 523 patients; 269 pre-COVID and 254 during COVID. While the overall number of cases declined, a significant increase in advanced stage cancers was noted during COVID (P = 0.04). The adjusted incidence rates showed a nuanced decrease from approximately 33 cases per 100,000 pre-COVID to 31 during COVID.

CONCLUSION

This retrospective study suggests a modest decline in lung cancer incidence and an increase in advanced stages during COVID. Further comparisons with national data indicate a similar trend across Germany, with a decrease of about 3 % in lung cancer diagnoses post-2020, highlighting potential pandemic impacts on cancer detection.

ALCAM-mediated cDC1 CD8 T cells interactions are suppressed in advanced lung tumors

Conventional type 1 dendritic cells (cDC1) are critical regulators of anti-tumoral T-cell responses. The structure and abundance of intercellular contacts between cDC1 and CD8 T cells in cancer tissues is important to determine the outcome of the T-cell response. However, the molecular determinants controlling the stability of cDC1-CD8 interactions during cancer progression remain poorly investigated. Here, we generated a genetic model of non-small cell lung cancer crossed to a fluorescent cDC1 reporter (KP-XCR1venus) to allow the detection of cDC1-CD8T cell clusters in tumor tissues across tumor stages. We found that cDC1-CD8 clusters are abundant and productive at the early stages of tumor development but progressively diminish in advanced tumors. Transcriptional profiling and flow cytometry identified the adhesion molecule ALCAM/CD166 (Activated Leukocyte Cell Adhesion Molecule, ligand of CD6) as highly expressed by lung cDC1 and significantly downregulated in advanced tumors. Analysis of human datasets indicated that ALCAM is downregulated in non-small cell lung cancer and its expression correlates to better prognosis. Mechanistically, triggering ALCAM on lung cDC1 induces cytoskeletal remodeling and contact formation whereas its blockade prevents T-cell activation. Together, our results indicate that ALCAM is important to stabilize cDC1-CD8 interactions at early tumor stages, while its loss in advanced tumors contributes to immune evasion.

Breaking-Down Tumoral Physical Barrier by Remotely Unwrapping Metal-Polyphenol-Packaged Hyaluronidase for Optimizing Photothermal/Photodynamic Therapy-Induced Immune Response

The therapy of solid tumors is often hindered by the compact and rigid tumoral extracellular matrix (TECM). Precise reduction of TECM by hyaluronidase (HAase) in combination with nanotechnology is promising for solid tumor therapeutics, yet remains an enormous challenge. Inspired by the treatment of iron poisoning, here a remotely unwrapping strategy is proposed of metal-polyphenol-packaged HAase (named PPFH) by sequentially injecting PPFH and a clinically used iron-chelator deferoxamine (DFO). The in situ dynamic disassembly of PPFH can be triggered by the intravenously injected DFO, resulting in the release, reactivation, and deep penetration of encapsulated HAase inside tumors. Such a cost-effective HAase delivery strategy memorably improves the subsequent photothermal and photodynamic therapy (PTT/PDT)-induced intratumoral infiltration of cytotoxic T lymphocyte cells and the cross-talk between tumor and tumor-draining lymph nodes (TDLN), thereby decreasing the immunosuppression and optimizing tumoricidal immune response that can efficiently protect mice from tumor growth, metastasis, and recurrence in multiple mouse cancer models. Overall, this work presents a proof-of-concept of the dynamic disassembly of metal-polyphenol nanoparticles for extracellular drug delivery as well as the modulation of TECM and immunosuppressive tumor microenvironment.

The phosphatidylserine targeting antibody bavituximab plus pembrolizumab in unresectable hepatocellular carcinoma: a phase 2 trial

Immune checkpoint inhibitors targeting PD-1/L1 have modest efficacy in hepatocellular carcinoma as single agents. Targeting membranous phosphatidylserine may induce pro-inflammatory and -immune stimulating effects that enhance immunotherapy activity. This hypothesis was tested in a single-arm phase 2 trial evaluating frontline bavituximab, a phosphatidylserine targeting antibody, plus pembrolizumab (anti-PD-1) in patients with unresectable hepatocellular carcinoma (NCT03519997). The primary endpoint was investigator-assessed objective response rate among evaluable patients, and secondary end points included progression-free survival, incidence of adverse events, overall survival, and duration of response. Among 28 evaluable patients, the confirmed response rate was 32.1%, which met the pre-specified endpoint, and the median progression-free survival was 6.3 months (95% CI, 1.3-11.3 months). Treatment related-adverse events of any grade occurred in 45.7% of patients, with grade 3 or greater adverse events in 14.3% of patients. Adverse events of any cause were observed in 33 patients (94.3%), with grade 3 or greater adverse events in 11 patients (31.4%). Prespecified exploratory analyses of baseline tumor specimens showed that a depletion of B cells, and the presence of fibrotic tissue and expression of immune checkpoints in stroma was associated with tumor response. These results suggest that targeting phosphatidylserine may lead to synergistic effects with PD-1 blockade without increasing toxicity rates, and future studies on this therapeutic strategy may be guided by biomarkers characterizing the pre-treatment tumor microenvironment.

Modeling Molecular Pathogenesis of Idiopathic Pulmonary Fibrosis-Associated Lung Cancer in Mice

Idiopathic pulmonary fibrosis (IPF) is characterized by progressive, often fatal loss of lung function due to overactive collagen production and tissue scarring. Patients with IPF have a sevenfold-increased risk of developing lung cancer. The COVID-19 pandemic has increased the number of patients with lung diseases, and infection can worsen prognoses for those with chronic lung diseases and disease-associated cancer. Understanding the molecular pathogenesis of IPF-associated lung cancer is imperative for identifying diagnostic biomarkers and targeted therapies that will facilitate prevention of IPF and progression to lung cancer. To understand how IPF-associated fibroblast activation, matrix remodeling, epithelial-to-mesenchymal transition (EMT), and immune modulation influences lung cancer predisposition, we developed a mouse model to recapitulate the molecular pathogenesis of pulmonary fibrosis-associated lung cancer using the bleomycin and Lewis lung carcinoma models. We demonstrate that development of pulmonary fibrosis-associated lung cancer is likely linked to increased abundance of tumor-associated macrophages and a unique gene signature that supports an immune-suppressive microenvironment through secreted factors. Not surprisingly, preexisting fibrosis provides a pre-metastatic niche and results in augmented tumor growth, and tumors associated with bleomycin-induced fibrosis are characterized by a dramatic loss of cytokeratin expression, indicative of EMT.

IMPLICATIONS

This characterization of tumors associated with lung diseases provides new therapeutic targets that may aid in the development of treatment paradigms for lung cancer patients with preexisting pulmonary diseases.

WITHDRAWN: Oncogenic KRAS G12D extrinsically induces an immunosuppressive microenvironment in lung adenocarcinoma

This manuscript has been withdrawn by the authors due to a dispute over co-first authorship that is currently being arbitrated by the medical school at our institution. Therefore, the authors do not wish this work to be cited as reference for the project. Upon completion of the arbitration process, we will take steps to revert the current withdrawn status. If you have any questions, please contact the corresponding author.

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.

The cancer-immunity cycle: Indication, genotype, and immunotype

The cancer-immunity cycle provides a framework to understand the series of events that generate anti-cancer immune responses. It emphasizes the iterative nature of the response where the killing of tumor cells by T cells initiates subsequent rounds of antigen presentation and T cell stimulation, maintaining active immunity and adapting it to tumor evolution. Any step of the cycle can become rate-limiting, rendering the immune system unable to control tumor growth. Here, we update the cancer-immunity cycle based on the remarkable progress of the past decade. Understanding the mechanism of checkpoint inhibition has evolved, as has our view of dendritic cells in sustaining anti-tumor immunity. We additionally account for the role of the tumor microenvironment in facilitating, not just suppressing, the anti-cancer response, and discuss the importance of considering a tumor's immunological phenotype, the "immunotype". While these new insights add some complexity to the cycle, they also provide new targets for research and therapeutic intervention.

Intravenous administration of BCG in mice promotes natural killer and T cell-mediated antitumor immunity in the lung

Intravesical administration of Bacillus Calmette-Guérin (BCG) was one of the first FDA-approved immunotherapies and remains a standard treatment for bladder cancer. Previous studies have demonstrated that intravenous (IV) administration of BCG is well-tolerated and effective in preventing tuberculosis infection in animals. Here, we examine IV BCG in several preclinical lung tumor models. Our findings demonstrate that BCG inoculation reduced tumor growth and prolonged mouse survival in models of lung melanoma metastasis and orthotopic lung adenocarcinoma. Moreover, IV BCG treatment was well-tolerated with no apparent signs of acute toxicity. Mechanistically, IV BCG induced tumor-specific CD8+ T cell responses, which were dependent on type 1 conventional dendritic cells, as well as NK cell-mediated immunity. Lastly, we also show that IV BCG has an additive effect on anti-PD-L1 checkpoint inhibitor treatment in mouse lung tumors that are otherwise resistant to anti-PD-L1 as monotherapy. Overall, our study demonstrates the potential of systemic IV BCG administration in the treatment of lung tumors, highlighting its ability to enhance immune responses and augment immune checkpoint blockade efficacy.